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When Worlds Collide: Discussion Questions!
While watching the PBS documentary When Worlds Collide, please take notes on the following subjects:
• The Reconquista of Spain
• The role of the Catholic Church in the Spanish Empire
• The sistema de castas (caste system) in Latin America
• The impact of silver in Latin America, Spain, and the global trade
Then, after watching the documentary, answer ONE of the following sets of discussion questions on a separate sheet of paper:
1. How did the Reconquista result in the creation of a caste system in Spain? How did this caste system affect the social hierarchy in Latin America? Was this caste system ultimately successful in achieving its stated goals?
2. How can religion be used as a means of imperial control? How did this control show up in Latin America? Provide specific examples to demonstrate your conclusion.
3. Why was silver so important to the Spanish Empire? What were some of the effects of the global silver trade on Latin America? On Spain? On other parts of the globe?
Be prepared to turn in your response at the start of class on Tuesday.
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"edu_int_score": 4,
"edu_score": 4.15625,
"fasttext_score": 0.9986968636512756,
"language": "en",
"language_score": 0.901750922203064,
"url": "https://gallowayapworld.wordpress.com/2019/03/"
}
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fiber splicing
What is Fiber Splicing and types
Fiber splicing is basically joining of two fiber optic cables together. To understand Splicing, we need to understand the fiber cable structure first. The Fiber cable is made of 3 concentric layers:
Core: This central section of fiber and made of silica. The core serves to transmit the light. The larger the core, the more light that will be transmitted into the fiber.
Cladding: It is the first layer around the core. It is also made of silica, but not with the same composition as the core. The function of the cladding is to provide a lower refractive index at the core interface in order to cause reflection within the core so that light waves are transmitted through the fiber.
Coating: Coating is the first non-optical layer around the cladding. The coating typically consists of one or more layers of a polymer that protect the inside structure against mechanical, physical or environmental damage. The fiber jacket has several major attributes, including bending ability, abrasion resistance, static fatigue protection, toughness, moisture resistance, and the ability to be stripped. Fiber optic cable jackets are made in different colors for color-coding identification.
Fiber splicing is joining of either core or clad. Cladding alignment is a passive alignment that relies on the accurate pre-alignment of fiber V-grooves that grip the outer surface or cladding of the fiber. The core alignment fusion splicers actually align the fiber’s core or centermost silica where light actually travels along the fiber’s path. Core alignment splicing is currently the most commonly used fusion splicing technology. This provides for precise fiber alignment, resulting in a typical splice loss of the only 0.02dB. Compared to cladding alignment, it is more expensive, more powerful and flexible, and less sensitive to variations in the cable and environment. Fiber termination with connector is another popular choice where we connect two fibers to create a temporary joint. Fiber Splicing on the other hand is permanent connections between two fibers.
fusion splicing
Types of Fiber Optic Splicing:
There are two types of splices: fusion and mechanical.
Mechanical Splices are alignment gadgets that hold the ends of two fibers together with some index matching gel or glue between them. There are a number of types of mechanical splices, like little glass tubes or V-shaped metal clamps. Many mechanical splices are used for restoration, but they can work well with both singlemode and multimode fiber, with practice. If you want the splices to be made quickly and easily, the mechanical splice is a better choice. A typical example of this method is the use of connectors to link fibers.
Both fusion splicing and mechanical splicing method have their advantages and disadvantages. The fusion one provides a lower level of loss and a higher degree of permanence than mechanical splicing. However, this method requires the use of the expensive fusion splicing equipment.
Looking for Fiber Optic cabling, contact us for all type of Fiber repair, maintenance, slicing and termination services.
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"edu_int_score": 4,
"edu_score": 3.859375,
"fasttext_score": 0.4541669487953186,
"language": "en",
"language_score": 0.914476215839386,
"url": "https://www.cablify.ca/what-is-fiber-splicing-and-types/"
}
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Claremont Primary and Nursery School
A Brighter Future for Everyone
Activity 1: Galileo Galilei
Watch the video below all about Galileo Galilei - make some notes of interesting points while you watch the video. Once you've watched the video, your activity is below.
Now, using the information in the video and the notes you have made, you are going to write a biography all about Galileo. Remember, a biography is the story of someone's life which is written by someone else. Below is a checklist to help you, it includes all the key features of a biography which you should include.
Activity 2: Adding Decimals
Refresh your memory of adding decimals by watching the video here. Once you have watched the video, complete the activity here in an exercise book or on some blank paper.
Activity 3: Maths Challenge
Have a go at solving the challenge below. Can you find all the possible answers?
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"edu_int_score": 4,
"edu_score": 3.515625,
"fasttext_score": 0.021423697471618652,
"language": "en",
"language_score": 0.9097506403923035,
"url": "https://www.claremontnottingham.co.uk/monday-2023/"
}
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Kids Web Japan
Web Japan > Kids Web Japan > Virtual Culture > Yabusame & Kyudo > Japanese Archery (Kyudo)
Virtual Culture
Yabusame & Kyudo
Japanese Archery (Kyudo)
About Japanese Archery
The bow and arrow began to be used more than 10,000 years ago for hunting and in war. In the Nara (710-794) and Heian (794-1185) periods they were utilized in rituals dedicated to the gods; it was around this time that archery made its appearance in events held at the Imperial court.
In 1543 firearms were introduced to Japan by a shipwrecked Portuguese who landed on Tanegashima, an island off Kyushu that's part of present-day Kagoshima Prefecture. After this, the role of the bow and arrow in battle declined, but as members of the ruling class, warriors continued to train themselves in archery - called kyudo in Japanese, meaning "the way of the bow" - because they considered it important as a mark of their refinement.
An event called toshiya was held during the Edo period (1603-1868) at Sanjusangendo (the main hall of the temple Rengeoin in Kyoto) in which warriors would compete in archery to see who had the greatest physical and mental strength.They would try to shoot arrows through the length of the long, narrow hall - 2.2 meters (2.4 yards) wide, 5 meters (5.5 yards) high, and 120 meters (131 yards) long - without hitting the walls, floor, or ceiling. What's more, each contestant would have to spend an entire day and night shooting arrows in sitting position.
Warriors who were confident of their archery skills would enter the contest and compete to see who could make the most good shots. The best archer in toshiya was Wasa Daihachiro of the Kishu clan, who took 13,053 shots in a single contest, out of which 8,133 were successful.
In the Meiji era (1868-1912) kyudo was brought into the school curriculum, and today many universities, high schools, and middle schools offer archery instruction either in class or as an extracurricular activity. Since archers can adjust the tension of the bow according to their own strength, kyudo is popular as a sport that men and women of all ages can enjoy.
At Kyoto's Sanjusangendo, where the toshiya contests were once held, a national tournament takes place every year on Coming-of-Age Day (January 15) in which each archer aims several arrows at a target 60 meters (66 yards) away. Over 1,000 people participate in the contest each year.
Photos (from top): Many women participate in this ancient sport; one famous contest is held at Ise Shrine. (All Nippon Kyudo Federation)
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"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.6875,
"fasttext_score": 0.03003031015396118,
"language": "en",
"language_score": 0.9731343388557434,
"url": "https://web-japan.org/kidsweb/virtual/yabusame/yabusame03.html"
}
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Vaccinating your rabbit
Vaccinating your rabbit
Vaccinating your rabbit
Rabbits are becoming a popular choice of family pet and its important to remember that they need to be vaccinated just like a cat or a dog. There are three diseases which are seen frequently in rabbits, two of which are caused by viruses which can be vaccinated against:
• Myxomatosis
• VHD (Viral Haemorrhagic Disease)
In order to prevent your rabbit getting sick, make sure you book them in for an annual vaccination (both indoor and outdoor rabbits).
How can your rabbit get sick?
Your pet rabbit can become infected either by direct exposure to infected wild rabbits or more commonly from biting insects such as rabbit and cat fleas or midges. Viruses can also be spread through objects that infected rabbits have been exposed to. VHD can survive for months in the environment so even indoor rabbits are at risk.
For example, the hay and fresh food you feed your rabbit might have been harvested from land where wild rabbits grazed or you could bring the virus into your home via your car wheels, dogs paws, clothes or shoes.
When should you vaccinate your rabbit?
Vaccination of your rabbit against these two infectious diseases can be carried out once your rabbit is just 6 weeks old. The vaccine protects your own pet and prevents it from being a carrier of disease and spreading infection. Immunity to these diseases does not last indefinitely so regular updates are vital to maintain this.
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.609375,
"fasttext_score": 0.1590840220451355,
"language": "en",
"language_score": 0.9508264660835266,
"url": "https://www.treatyveterinaryclinic.com/exotic-animals/vaccinating-your-rabbit/"
}
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2-1 Warmers
Topic Progress:
A warmer is an activity at the start of the class to warm up the learners and get them better prepared to study. They tend to be short, dynamic activities.
Watch the video below and answer the questions that follow.
1 What do you think of this warmer? Could you use it with your students? Why? Why not?
2 Describe a warmer that you have used / would like to try in the future.
Write your answer to 1 and 2 in the LMT 2019 forum.
EVT 2019
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"edu_int_score": 4,
"edu_score": 3.53125,
"fasttext_score": 0.9788768887519836,
"language": "en",
"language_score": 0.9467169642448425,
"url": "https://anglolangonline.com/topic/2-1-warmers-copy/"
}
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What is Pastel and why is it such a special medium?
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Pastel is a dry medium of pure pigment, the same pigment used in making all fine art paints. When a pastel painting is framed under glass, it is the most permanent of all mediums, as it has no liquid binder which may cause darkening, fading or cracking with time, as can be the case with some mediums. Pastels from the 16th Century still exist today, as fresh as the day they were painted.
Caroline Lewallen - Birches from our 32nd Annual Exhibition
Genevieve Monnier, in her book “Pastels from the 16th to the 20th Century” describes pastels as –
“…powdered colour with an infinite range of shades and gradations of unfading freshness and intensity, spanning more then 1650 nuances of the colour spectrum and peculiarly fitted for ease and rapidity of handling, immediate transcription of an emotion or idea, easily effaced, easily reworked and blended. The pigments can be rubbed in, made luminous and velvety, or given a soft and silky matness of grain. Pastel is line and colour at once. It can also be built up into rich skeins of blended lines, into rapid jottings of all colours creating a dense and brilliant texture. Pastel is a medium of unsuspected range and diversity.”
Pastel does not refer to pale colour, as the word is commonly used in fashion terminology, instead it is derived from the French worked ‘pastiche’. The pure powdered pigment is ground to a ‘paste’ with a small amount of gum binder and then rolled into sticks. The infinite varieties of colours range from soft and subtle, to bold and brilliant. In fact the luminosity of the pastel medium is a constant source of amazement amongst viewers.
Many pastel works hang in National Galleries around the world. During the 17th and 18th centuries notable artists such as Le Brun, Boucher, Lemoine, Carriera and La Tour created some of the most exquisite portraits using pastels. In the 19th and 20th centuries – Toulouse-Lautrec, Degas, Millet, Manet, Gauguin, Whistler, Cassatt, Picasso, Klee, Chagall and Pollock are just a few of the many familiar masters who used the pastel medium.
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"edu_score": 3.5,
"fasttext_score": 0.019825518131256104,
"language": "en",
"language_score": 0.9407418966293335,
"url": "https://exhibition2020vicpastel.g247.com.au/news/40133/what-is-pastel-and-why-is-it-such-a-special-medium/?type_fr=4"
}
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What is duty cycle in electronics
How is duty cycle calculated?
Determine the duty cycle, represented by “D,” through the formula D = PW/T. As an example, if PW is 0.02 seconds and T is 0.05 seconds, then D = 0.02/0.05 = 0.4, or 40%.
What is duty cycle in op amp?
A duty cycle or power cycle is the fraction of one period in which a signal or system is active. Duty cycle is commonly expressed as a percentage or a ratio. A period is the time it takes for a signal to complete an on-and-off cycle.
What is duty cycle in PWM?
To describe the amount of “on time” , we use the concept of duty cycle. Duty cycle is measured in percentage. The percentage duty cycle specifically describes the percentage of time a digital signal is on over an interval or period of time. This period is the inverse of the frequency of the waveform.
What is a 100 duty cycle?
A piston compressor that specifies a 100 percent duty cycle does not mean it can run continuously, but that it can provide air at a specific pressure and flow 100 percent of the time with the help of a storage tank. … A compressor advertises a 100 percent duty cycle rating of 25 cfm at 100 psi.
What is a 10% duty cycle?
Duty cycle is a welding equipment specification which defines the number of minutes, within a 10 minute period, during which a given welder can safely produce a particular welding current. For example, a 150 amp. welder with a 30% duty cycle must be “rested” for at least 7 minutes after 3 minutes of continuous welding.
What is the unit of duty cycle?
The duty cycle can be expressed as a ratio or as a percentage. Suppose a disk drive operates for 1 second, then is shut off for 99 seconds, then is run for 1 second again, and so on. The drive runs for one out of 100 seconds, or 1/100 of the time, and its duty cycle is therefore 1/100, or 1 percent.
You might be interested: Portable power charger for cellphones & electronics
What is the difference between duty cycle and frequency?
Frequency is how often a signal switch between low voltage and high voltage. Frequency is expressed in cycles per second, or Hz. Duty cycle is percent of time that the signal stays at high level. It is typically expressed as the percentage of the period.
What is duty cycle on a multimeter?
Example: A 60% duty cycle is a signal that is on 60% of the time and off 40% of the time. … When measuring duty cycle, a digital multimeter displays the amount of time the input signal is above or below a fixed trigger level – the fixed level at which the multimeter counter is triggered to record frequency.
What is duty cycle in radar?
It should be obvious that the duty cycle is the “ratio” between the PEAK energy in the radar pulse and the AVERAGE energy expended over a specified period of time.
Is PWM AC or DC?
It is neither AC nor DC, but it is closer to being DC in waveform. PWM was often used to encode a RF signals with information. … The waveform causes a rise and fall in the magnetic field and allows the transformer to produce an output that more closely resembles AC.
How do you calculate PWM duty cycle?
In the case of the BASIC Stamp, the duty cycle can range from 0 to 255. Duty is literally the proportion of 1s to 0s output by the PWM command. To determine the proportional PWM output voltage, use this formula: (Duty ÷ 256) x 5 V.
You might be interested: Electronics for the home
Why is PWM used?
Pulse width modulation is a great method of controlling the amount of power delivered to a load without dissipating any wasted power. The above circuit can also be used to control the speed of a fan or to dim the brightness of DC lamps or LED’s. If you need to control it, then use Pulse Width Modulation to do it.
What does 40% duty cycle mean?
Duty cycle is the amount of time it may be operated at a given output without exceeding the temperature limits of its components, and it is measured using a 10-minute cycle. In our example, the welding machine has a duty cycle of 40% at when MIG welding at 285 amps/28 volts.
What is injector duty cycle?
The amount of time an injector is turned on to delivering fuel is known as injector duty cycle. This is measured as a percent, so 50% duty cycle indicates that the injector is held open and held closed for an equal amount of time.
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"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.53125,
"fasttext_score": 0.9759462475776672,
"language": "en",
"language_score": 0.9276604652404785,
"url": "https://www.electronicfastener.com/interesting/what-is-duty-cycle-in-electronics.html"
}
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Scientists Want To Engineer A Spicy Tomato
Scientists have long known that tomatoes and chili peppers were sort of distant cousins in the food. Scientists believe these two types of fruit (scientifically speaking) share an ancestor from which they split off more than 19 million years ago. Despite having split apart so long ago, tomatoes and chili peppers still share some common traits, and scientists want to use them to engineer a spicy tomato.
There are some major differences between the two plants. Tomatoes developed into friendly, nutrient-rich and fruit-like harvests, while the chili planet went “defensive” by developing capsaicinoids, which make it spicy and protect it from predators. However, a team of scientists still thinks the latest gene-editing techniques can be used to combine traits of the two plants together.
A new study describing the technique was published on Jan. 7 in the journal Trends in Plant Science. The research doesn’t aim to develop an entirely new type of spicy tomato, but rather, to produce large quantities of capsaicinoids for commercial use. The molecules of the materials are rich in nutritional and antibiotic characteristics, which are normally used to make painkillers and pepper spray used for protection.
Crossroads Capital up 55.8% YTD after 32.5% in 2019 explains how it did it
Jeffrey Aronson Crossroads CapitalCrossroads Capital is up 55.8% net for this year through the end of October. The fund released its 2019 annual letter this month after scrapping its previous 2019 letter in March due to the changes brought about by the pandemic. For 2019, the fund was up 32.5% net. Since inception in June 2016, Crossroads Capital Read More
“Engineering the capsaicinoid genetic pathway to the tomato would make it easier and cheaper to produce this compound, which has very interesting applications,” senior author and plant biologist Agustin Zsögön of Brazil’s Federal University of Viçosa said in a press release. “We have the tools powerful enough to engineer the genome of any species; the challenge is to know which gene to engineer and where.”
To engineer a spicy tomato, the scientists are actually trying to manipulate capsaicinoids, which cause irritation and a burning sensation in humans and other mammals. Chili peppers and the burning sensation they cause protect them from mammals that would otherwise eat them, although birds don’t have a reaction to those molecules. Scientists have found 23 types of capsaicinoids in chili peppers.
Previous gene identification work has shown that tomatoes also have genes which are essential for capsaicinoid production, but they don’t have the necessary power to convert these genes into those molecules. Now scientists want to engineer a spicy tomato which will have the ability to produce capsaicinoids.
“In theory you could use these genes to produce capsaicinoids in the tomato,” Zsögön said. “Since we don’t have solid data about the expression patterns of the capsaicinoid pathway in the tomato fruit, we have to try alternative approaches. One is to activate candidate genes one at a time and see what happens, which compounds are produced. We are trying this and a few other things.”
Now that the researchers have sequenced the chili pepper genome, they believe they will be able to engineer a spicy tomato. According to the researchers, their study will help scientists understand the evolution of plants and their unique botanical traits.
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.609375,
"fasttext_score": 0.02377951145172119,
"language": "en",
"language_score": 0.9502319097518921,
"url": "https://www.valuewalk.com/2019/01/scientists-engineer-a-spicy-tomato/"
}
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Conditional evaluation in detail
While writing any code, we are often confronted with situations where we need to make some decisions based on a set of rules or predefined business logic. In such cases, we would generally expect the code to be intelligent enough that it can take the right path accordingly. Here is when conditional evaluation comes into the picture.
Let's have a look at the example of FizzBuzzHere, we will be implementing the famous FizzBuzz program which states that, for any given range of numbers (let's say 1 to 30), print Fuzz instead of the number for multiples of 3 and Buzz for multiples of 5. For numbers which are both divisible by 3 and 5, the program should print FizzBuzz.
julia> for i in 1:30 if i % 3 == 0 && i ...
Get Learning Julia now with O’Reilly online learning.
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"edu_int_score": 4,
"edu_score": 3.640625,
"fasttext_score": 0.11339128017425537,
"language": "en",
"language_score": 0.9205030202865601,
"url": "https://www.oreilly.com/library/view/learning-julia/9781785883279/b45182e8-81a6-4582-b76c-318cf7d44a1f.xhtml"
}
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What Is an Autoregressive Model?
Python Tutorials 7 min read
autoregressive model, ar model, the autoregressive model
Blog / Python Tutorials / What Is an Autoregressive Model?
autoregressive model, ar model, the autoregressive model
In time-series, we often observe similarities between past and present values. That’s because we encounter autocorrelation within such data. In other words, by knowing the price of a product today, we can often make a rough prediction about its valuation tomorrow. So, in this tutorial, we’re going to discuss a model that reflects this correlation. – the autoregressive model.
What is an Autoregressive Model?
The Autoregressive Model, or AR model for short, relies only on past period values to predict current ones. It’s a linear model, where current period values are a sum of past outcomes multiplied by a numeric factor. We denote it as AR(p), where “p” is called the order of the model and represents the number of lagged values we want to include.
For instance, if we take X as time-series variable, then an AR(1), also known as a simple autoregressive model, would look something like this:
Xt = C + ϕ1Xt-1 + ϵt
Let’s go over the different parts of this equation to make sure we understand the notion well.
What is Xt-1?
For starters, Xt-1 represents the value of X during the previous period.
Let’s elaborate.
If “t” represents today and we have weekly values, then “t-1” represents last week. Hence, Xt-1 depicts the value recorded a week ago.
What is ϕ1?
The coefficient ϕ1 is a numeric constant by which we multiply the lagged variable (Xt-1). You can interpret it as the part of the previous value which remains in the future. It’s good to note that these coefficients should always be between -1 and 1.
Let me explain why.
If the absolute value of the coefficient is greater than 1, then over time, it would blow up immeasurably.
This idea can seem confusing at first. So let’s take a look at a mathematical example.
Say, we have a time-series with 1000 observations and ϕ1 = 1.3 and C=0.
Then, X2 = 0 + 1.3 X1
Since X3 = 1.3 X2, we can substitute (1.3 X1) for X2 and get X3 = 1.3(1.3 X1) = 1.32 X1. Then, as the more periods accumulate (e.g. X50), the more the coefficient increases (1.349 X1).
When we get to the 1000th period, we would have X1000 = 1.3999 X1. This implies that the values keep on increasing and end up much higher than the initial one. This is obviously not a reliable way to predict the future.
What is ϵt?
Okay, now the only part of the equation we need to break down is ϵt. It’s called the residual and represents the difference between our prediction for period t and the correct value (ϵt = yt – ŷt). These residuals are usually unpredictable differences because if there’s a pattern, it will be captured in the other incumbents of the model.
How do we interpret the Autoregressive Model?
Now that we know what all the parts of the model represent, let’s try to interpret it. According to the equation, values at a given period (Xt) are equal to some portion (ϕ1) of values in the last period (Xt-1), plus some constant benchmark and unpredictable shocks ϵ t.
It is vital to understand that we don’t use just any autoregressive model on a given dataset. We first need to determine how many lags (past values) to include in our analysis.
Autoregressive Model with More Lags
For example, a time-series about meteorological conditions wouldn’t solely rely on the weather statistics a day ago. It’s realistic to say it would use data from the last 7 days. Hence, the model should take into account values up to 7 periods back.
From a mathematical point of view, a model using two lags (AR(2)) would look as follows:
Xt = C + ϕ1 Xt-1 + ϕ2 Xt-2 + ϵt
As you can expect, a more complicated autoregressive model would consist of even more lagged values Xt-n, and their associated coefficients, ϕn .
The more lags we include, the more complex our model becomes.
The more complicated the model, the more coefficients we have to determine and as a result, the more likely it is that some of them would not be significant.
Now, in general, a model that takes into account more data to make a prediction is usually better. However, if the coefficients (ϕ1, ϕ2,… ϕn) are not significantly different from 0, they would have no effect on the predicted values (since ϕk Xt-k = 0), so it makes little sense to include them in the model.
Of course, determining the significance of these coefficients cannot be done by hand.
Lucky for us, Python is well-suited for the job. With convenient libraries like Pandas and Statsmodels, we can determine the best-fitting autoregressive model for any given data set.
If you want to learn more about implementing autoregressive models in Python, or how the model selection process works, make sure to check out our step-by-step Python tutorials.
If you’re new to Python, and you’re enthusiastic to learn more, this comprehensive article on learning Python programming will guide you all the way from the installation, through Python IDEs, Libraries, and frameworks, to the best Python career paths and job outlook.
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{
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"edu_int_score": 4,
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"fasttext_score": 0.3922494053840637,
"language": "en",
"language_score": 0.9048191905021667,
"url": "https://365datascience.com/autoregressive-model/"
}
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The Black Hole Monument is a controversial part of the Indian History; an atrocity that befell its victims.
To know about the actual history of the Black Hole Monument in Kolkata, we are to travel back to the past, during the British rule in India. The British rein in India was memorable and a plethora of chest thumping as well as awful events and incidents took place during this historic dispensation in the city. One British survivor, John Holwell, elicits and helps to unravel the mystery behind the construction of the monument known as the black hole. This has been the only source of information that witnessed the actual incident and was a living witness.
He states that owing to the siege of Calcutta siraj – ud – daulah, 146 people were captivated as prisoners and were confined in a room that measured about 14 feet by 8 feet. The temperature of the place, the ventilation of the area was intolerable and hence, 123 people perished and lost their lives over there, owing to heat stroke and extreme suffocation. Immense luck was bestowed upon the remaining 23 who were fortunately able to survive in this condition that was in a Pell mell. The Black Hole Monument is counted among other architectural extravagances of the nation especially of the British Empire.
Later, John Holwell became the Governor of Bengal and the Black Hole Monument earned fame and repute in the city of passion , palaces and joy . Criticisms and controversies were there as the filth in the air as some did not agree upon whatever john holwell did opine. it is surprising or rather shocking to know that it is believed that somehow the British’s were able to escape through a few secret tunnels attached to river ports and save their lives there after .the ritishes who survived were then sent to Madras with the help of ships awaiting on the port of the river Hooghly .
It was completely ironical for the British themselves to state the number of prisoners who lost their lives but being the direct and living witness of this kerfuffle and this bedlam condition their accounts had to be taken into serious consideration by the rest of the population and the historians. In fact, John Howell was the person who endeavoured to build a monument upon that specific place. Further research had off course been done upon the matter. A plethora of archaeological research works had been conducted after putting down John Holwell’s words. This is all about putting together the pieces of puzzle in a juxta position to reframe the history of the Black Hole Monument.
The history of the Black Hole Monument in Kolkata is rare and is uniquely interesting as well. the further research work acts as the ‘icing on the cake ‘ where as the arguments upon John Holwell’s opinion and the criticisms act as ‘ cherry on top ‘ . Though the specific incident had been a tragic one and massive life loss occurred in the city, this has been recorded as one of the most historic events of utmost significance in the pages of history. It is sometimes said the monument disappeared around 1822 to e rebuilt by Lord Curzon.
Under the firmament of pandemonium in the country this was a real topsy turvy of the contemporary condition. The monument is said to e rebuilt y lord Curzon in the year 1901 in the south west corner of the writers building .this complete building, shifting, relocating and rebuilding was going on during the height of the Indian freedom and independence movement in 1940. This was never stable during the British rule and was again relocated y the then dispensation into the st John’s church compound. The dungeon and the prisoners of war with their sufferings did create a whole new portion of history and added to the heritage and cloture of India. This makes a special place in the pages of the history books and in the warmest nooks of our hearts.
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Publication Date
The Peregrine Falcon (Falco peregrinus) was believed to be extirpated as a breeding species in Virginia by the early 1960s. An aggressive restoration program was initiated in 1978 that included the release of 115 captive-reared birds on the Coastal Plain (1978-1985) and 127 birds in the mountains (1985-1993). This program resulted in the first breeding of the modern era in 1982. Since this time, the population has proceeded through a rapid establishment phase followed by a consolidation phase. However, more than 95% of all breeding activity over the past 30 years has occurred on the Coastal Plain with very limited breeding within the historic mountain range. Since 2000 a dedicated translocation program has moved more than 245 birds from eyries on the coast to hack sites in the mountains in an effort to restore the mountain breeding population. Restoration of the breeding population in the mountains continues to be a management priority for the state. In 2015, Virginia supported a known falcon population of 26 breeding pairs including 23 within the Coastal Plain, 1 in the Piedmont and 2 in the mountains. This represents the third consecutive year that the population has exceeded 25 breeding pairs. New breeding territories were documented on a smoke stack within a power station and on a building within an urban area. Four territories that have supported pairs in recent years were not occupied in 2015. The population achieved an overall success rate of 80.7% producing 56 young to banding age. The reproductive rate was 2.15 young/occupied territory which is above the level required for population maintenance. The population continues to benefit from the efforts of a large community of agencies, corporations and individuals. Efforts continued in 2015 to identify breeding adults via field-readable bands to better understand dispersal and demography throughout the mid-Atlantic region. Eighteen adults within Virginia were identified including 10 females and 8 males. Birds varied in age from 2 to 15 years. Of the 14 birds where hatching location could be determined, 9 originated in Virginia, 4 originated in New Jersey and 1 originated in Maryland. Five birds that were banded as nestlings in Virginia were identified on breeding territories in other states including 2 in Pennsylvania and 3 in New Jersey. Efforts to identify marked peregrines should continue since these birds are contributing to our understanding of effective population size and regional management.
Abundance/distribution;Breeding/Demography/Population Dynamics
Peregrine Falcon
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Quick Answer: What Is A Constrained Area?
How do you use constrained in a sentence?
Constrained sentence examplesHe snatched two more oranges before the magic constrained his movement.
In 1752, constrained to secure some position in the world, he accepted a tutorship in a family resident in Livonia, but only retained it a few months.More items….
Why do we need social constraints?
we need social constraints because it is the factor that gives us knowledge to live in a society and it develops culture on us. The human characters are maintained because of this constraints over us. so it is very necessary.
Why do we need constraints Class 11?
Constraints are necessary to develop respect for the views and beliefs of others. It is necessary for the creation of a society. Absence of constraint would lead to the imposition of beliefs and ideas of stronger groups eventually leading to conflict. Constraints are required to control violence and settle disputes.
Why do we need constraints in SQL?
SQL constraints are used to specify rules for the data in a table. Constraints are used to limit the type of data that can go into a table. This ensures the accuracy and reliability of the data in the table. If there is any violation between the constraint and the data action, the action is aborted.
What is the meaning of time constraints?
The definition of time constraint refers to the limitations on the start and end times of a project. … While a time constraint is defined as a limitation imposed on you by someone else, a time restraint is defined as an inability to reach a goal because of your own shortage of time.
What is the meaning of combative?
What does it mean to feel constrained?
: to feel that one must do something She felt constrained to apologize for the harm she’d done.
What is a constraint example?
What’s another word for constrained?
What is another word for constrained?shybashfulfrustratedashamedfearfuluncomfortableuneasyrabbitydistrustfulunassured120 more rows
Why do we need constraint?
We need some constraints or else society would descend into chaos. (i)Differences may exist between people regarding their ideas and opinions, they may have conflicting ambitions, they may compete to control scarce resources. … Therefore every society needs some mechanisms to control violence and settle disputes.
What is the opposite of constrain?
Opposite of to limit, restrict, or inhibit. lose. aid. allow. assist.
What does constrained mean?
b : to restrict the motion of (a mechanical body) to a particular mode. 2 : compress also : to clasp tightly. 3 : to secure by or as if by bonds : confine constrained to a dungeon broadly : limit.
What happens when you are constrained by something?
Constrained contains the word strained for a reason. Mostly because anyone that’s constrained is feeling a fair amount of strain because of it. In addition to referring to unnatural or uncharacteristic behavior, being constrained can also mean being held back or forced to do something you don’t want to do.
What is the difference between restraint and constraint?
The seminal difference between a constraint and a restraint is that a constraint is an absolute restriction imposed on the calculation, while a restraint is an energetic bias that tends to force the calculation toward a certain restriction.
What defy means?
verb (used with object), de·fied, de·fy·ing. to challenge the power of; resist boldly or openly: to defy parental authority. to offer effective resistance to: a fort that defies attack. to challenge (a person) to do something deemed impossible: They defied him to dive off the bridge.
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Propaganda - General Information
Types of Propaganda
Excerpts from SourceWatch
Propaganda shares many techniques with advertising or public relations; in fact, advertising and PR can be said to be propaganda promoting a commercial product. ... In a narrower and more common use of the term, propaganda refers to deliberately false or misleading information that supports a political cause or the interests of those in power.
The propagandist seeks to change the way people understand an issue or situation, for the purpose of changing their actions and expectations in ways that are desirable to the interest group. In this sense, propaganda serves as a corollary to censorship, in which the same purpose is achieved, not by filling people's heads with false information, but by preventing people from knowing true information.
What sets propaganda apart from other forms of advocacy is the willingness of the propagandist to change people's understanding through deception and confusion, rather than persuasion and understanding. The leaders of an organization know the information to be one sided or untrue but this may not be true for the rank and file members who help to disseminate the propaganda.
In an even narrower, less commonly used but legitimate sense of the term, propaganda refers only to false information meant to reassure people who already believe. The assumption is that, if people believe something false, they will constantly be assailed by doubts. Since these doubts are unpleasant, people will be eager to have them extinguished, and are therefore receptive to the reassurances of those in power. For this reason propaganda is often addressed to people who are already sympathetic to the agenda.
• White propaganda generally comes from an openly identified source and is not intentionally deceptive.
• Gray propaganda falls somewhere between white and black.
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Heritage Gateways
Official Sesquicentennial K-12 Education Project
Pioneer 1848-1868 Companies
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1848-1868, Black Pioneers
There were very few Blacks connected with the early Mormon Church and fewer still on the emigrant trails. There were, for example, only three Blacks in the pioneer company of 1847--Green Flake, Hark Lay, and Oscar Crosby. In the much bigger group of 1848, twenty-four more Blacks crossed the plains. Thereafter the records indicate a scattering of Black "servants" going west during the 1850s. Almost all of the servants mentioned in the sources were slaves of white southern converts, who saw no compelling reason for freeing their slaves just because they had become Mormons. Fortunately, most Blacks were later freed in Utah. On the trail, most of these slaves served as teamsters, herders, or cooks.
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Zoopharmacognosy is the ability of some animals to know, seek out and use certain plants for their medicinal value to cure what ails them.
This definition is my own because so far I haven't been able to find an "official" dictionary definition. The earliest use of the word I've found was in 19921.
Zoopharmacognosy is a relatively new field of study, so there is as yet no exhaustive body of research on the topic. However, this has not stopped Barnes & Noble from publishing a book about it.2
My own interest was drawn to to the subject by an article in Die Welt4 which cites the following anecdotal evidence by researchers observing primates:
• An orangutan, obviously suffering from a headache, held his head and went over to a certain plant and ate some of its flowers. He seemed to be better within an hour. At another time, when the researcher himself was suffering from a headache, he bravely followed the ape's example and found his headache abating soon afterward.
• Another pair of researchers, one of them Michael Huffman, currently the biggest name in zoopharmacognosy, observed a female chimpanzee who withdrew from the group because she was suffering from diarrhea. She sought out a mjonso tree, normally shunned by the chimpanzees because of its bitter and poisonous leaves and bark. This time, however, she peeled some of the bark from a twig, chewed on the pith and swallowed the juice. The next day the chimp was back to normal.
An analysis of the substances in the mjonso tree juices revealed 13 hitherto unknown substances with antibacterial, antiparasitic and even antitumor effects.3 It turns out the plant is valued by the African locals for its over 25 medicinal properties.
• Sometimes animals eat plant components for their physical properties rather than their chemistry. Chimpanzees are frequently observed to eat the bristly leaves of certain plants, swallowing them unchewed. These leaves have no nutritional value and pass the digestive system crinkled but intact. But closer examination of the leaves shows that they often trap parasitic worms from the animals' intestines on their bristles. Some evidence for the conscious use of these leaves is found in the fact that only sick chimpanzees eat the leaves, and mostly after the beginning of the rainy season, when the number of parasitic larvae and the danger of infection are at a maximum.
Other sources5 quote similar discoveries about primates and other animals, including bears, turtles and even a porcupine. Study of primates shows that knowledge about beneficial plants is passed on from parents to young during the long course of their upbringing. How other species acquire this knowledge is still a subject undergoing investigation.
1. Rodriguez, E. and R.W. Wrangham. 1992. Zoopharmacognosy: Medicinal plant use by wild apes and monkeys. Paper presented at the 1992 American Association for the Advancement of Science (AAAS) meetings. Chicago, Illinois.
2. Engel, Cindy. Wild Health. Barnes & Noble, January 2002.
3. http://veederandld.20m.com/greports/2501b.html
4. http://www.welt.de/daten/2002/04/20/0420med327251.htx
5. http://jinrui.zool.kyoto-u.ac.jp/CHIMPP/CHIMPP.html
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How do plants remember winter?
Martin Howard is a Professor at the John Innes Centre, one of a small cluster of research institutes in Norwich. In the fourth of our Celebrating Basic Plant Science series, he explains how he uses mathematical modelling to understand how plants remember winter cold and respond to it throughout the year.
How do plants ‘know’ the correct time to flower? Getting this timing right is vital for reproductive success; flowering in the middle of winter is unlikely to be optimal! Many factors are integrated together to make this critical decision, including the day length.
We have been studying one aspect of this question: How the plant Arabidopsis thaliana perceives and then remembers exposure to winter cold. This fundamental mechanism ensures that flowering doesn’t occur until winter has passed. Interestingly, this memory is quantitative – a longer winter means flowering is faster once it starts (see the image below). This process is a very nice example of what’s called an epigenetic phenomenon, as the plants store information about winter cold exposure even after the environmental stimulus (cold) has been removed.
So how is this information about cold stored? In Arabidopsis, this is centred on a gene called FLC (Flowering Locus C). When the plant is cold, the FLC gene is turned off. The products of this gene prevent flowering, so turning it off actually stimulates the plant to flower. Over recent years, we have learned a great deal about the operation of FLC and associated genes through genetics and biochemistry, in large part through the work of my experimental collaborator, Caroline Dean. However, despite all this knowledge it was still not clear overall how the epigenetic memory system worked. This was partly due to feedback among the different components, which made arriving at an intuitive understanding a very difficult task. For these reasons, we began to model the dynamics of FLC mathematically in the hope of making sense of these interactions and, we hoped, revealing some underlying simplicity in how the system operated.
Mathematical modelling turned out to be very informative and suggested that FLC gene silencing occurred in an all or nothing fashion inside each cell. (more…)
Celebrating Basic Plant Science: Siobhan Braybrook
The first in our series of Celebrating Basic Plant Science articles comes from Siobhan Braybrook, a Career Development Fellow at the Sainsbury Laboratory at the University of Cambridge. She explains her work on plant development and discusses why she thinks basic plant science is value for money.
In parts of India people have built ‘living bridges’ with traditional methods. Could developmental biology build the living bridges of the future?
How do we measure the importance of scientific works? Do we require immediate applications? Do we simply need to know? Both basic and applied science are important and vital for our sociological and scientific progress, but we tend to measure their impact with a very immediate and short ruler, one which is biased towards applied outcomes. Basic science is concerned with knowledge for knowledge’s sake, the desire to know. Applied science is directed towards a specific problem and it’s solution. Here, I propose that is impossible to anticipate the value of a basic scientific work beyond its immediate context, and that attempting to do so might just force us to narrow our field of imagination and innovation.
My group focuses on a basic scientific question- we would like to know how plants grow shapes. Our research definitely falls into the category of basic science as we pursue the answer to this question, not with a specific application in mind, but with a simple desire to know. But that does not mean that we don’t find applied directions during our pursuits.
Plant cells are pretty special to me because they exist in a box; the plant cell wall contains all of the other cell contents, allowing the cell to attain high pressures and also being the regulator of cell shape. We use biology, genetics, biochemistry, and materials science to understand how the cell wall controls cell, organ, and whole plant shape. As an example, we have shown with collaborators in France that new organ formation strictly requires a particular change in the cell wall, altered pectin chemistry. It was surprising that something as simple as pectin, the same thing used to make jellies set, was able to control whole plant shape by limiting new organ growth. These experiments have directed us to look at other growth processes that might be controlled, in part, by pectins in the cell wall.
From a basic science standpoint, our findings were very satisfying- we had found out something new and interesting. But they have also led us down some less familiar paths, into the realm of applied science. Can we take what we have learned about a biological material, the cell wall, and design man-made materials that also have the potential to grow? Could we one day place a small block of material on the ground and have it grow into a house? A car? Alternatively, if we understand how the cell wall controls growth, could we plant a seed that grows into a house frame? A chair? It is unlikely that any company would touch this idea without a very, very, very long pole at this time. It is too speculative, maybe even too crazy. But within the realm of basic science, we can continue to chip away at the possibility- with a freedom that does not require a final product right away, a freedom that allows us to grow our ideas along side our plants.
In closing, it is probably highly simplistic to separate basic and applied science. There is cross talk between the two, research projects that exist in a continuum, and research questions that are entangled. However, there are some very special things about basic science: you don’t need to know exactly where you are going in order to end up somewhere cool; you can explore things for the sake of knowledge which gives a lot of freedom; and sometimes you find out unexpected things that end up having massive applied impacts that you might never have anticipated. It is essential that we create a place for such scientific freedoms, that we don’t assume which pursuits have value before they have been investigated, and that we allow for the possibility of novel discoveries.
You can read Siobhan Braybrook’s research about pectin and new organ formation in Braybrook and Peaucelle 2013, PLoS ONE 8(3): e57813 and Peaucelle et al. 2001, Curr. Biol. 21:1720
Image credit: Screwtape via Flickr
Celebrating basic plant science with David Baulcombe
Categories: UKPSF
Comments: No Comments
Published on: May 10, 2013
Barbara McClintock discovered transposable elements when investigating irregular colouring in maize.
It’s now nearly a month since UK PlantSci 2013, and high time I wrote something about it on this blog. Rebecca Nesbit has written two posts about it already on the Society of Biology blog, and a New Phytologist meeting report will be coming out soon. The Weeding the Gems contribution to this collection of UK PlantSci nostalgia is a write-up of the second keynote talk by David Baulcombe.
David Baulcombe’s talk was a rallying cry in defence of basic research and plant science. He kicked it off with a whistle-stop history of important scientific achievements, all by scientists carrying out basic research on plants: Robert Hooke, who identified and labelled ‘cells’ for the first time when studying woody plant biomass in 1665; 19th century monk Gregor Mendel, whose peas were the first genetic model system; Russian botanist Dmitri Iwanowsk, who in 1892 was the first scientist to identify and characterise a virus; and Barbara McClintock, who discovered transposable elements in maize. More recently even than McClintock’s work, Argonaute proteins, tumour formation, and cellular totipotency were all identified first in plants (Bohmert et al. 1998, EMBO 17:170; Sussex 2008, Plant Cell 20:1189).
The scientists involved in the discoveries listed above were carrying out what they presumably viewed as interesting work, simply because they wanted to know the answer – pure science, but all with far-reaching consequences. Baulcombe commented than in the 21st Century research is impact-driven, so some of these pioneers may have struggled to get funding via today’s funding mechanisms.
Now, it is unfair to say that research today is all end-product focussed and impact driven. I know that the BBSRC and other funders worldwide fund basic plant science research regularly, and I highlight some of it here on this blog. Baulcombe’s main point in this first half of the talk was that basic excellent plant science research has to be celebrated in its own right rather than as a half-way point to a useful product in the future. (more…)
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Welcome , today is Friday, September 21, 2018
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Catheters are long, flexible tubes that are inserted into the body for various purposes, either to remove an unwanted substance or to instill nourishment or medication.
A relatively large catheter can be passed through the nose, down the throat and into the stomach to remove the contents of the stomach; for example, if someone has consumed a poisonous substance, a catheter can be used to remove a small sample of the stomach contents for laboratory testing. A catheter may also be used to pass liquid nourishment into the digestive tract, as in the case of someone unable to swallow for some reason. This catheter is called a nasogastric tube.
A smaller tube can be passed through the urethra into the bladder to empty its urine. Oftentimes after surgery or trauma an individual is unable to void and must have the bladder emptied. Sometimes these urinary catheters must be left in place; a small balloon near the end of the catheter is inflated to hold the catheter in the bladder.
Very long catheters are often passed through an incision in the thigh into an artery and into the heart; a doctor can then inject contrast agents into the patient to outline the coronary arteries. The physician can watch as the agent, which is visible on x rays, is injected and courses through the hearts arterial system. In this way a doctor can see a blockage and take measures to bypass it or remove it. These catheters have now been fitted with devices to open clogged arteries. Small balloons mash obstructions out of the way, and laser tips or whirring blades cut stubborn blockages from the arterial passage. Since there are no pain receptors inside blood vessels, passing the cardiac catheter is done under local anesthetic with the patient fully awake.
Still other catheters can be inserted through the trachea into the lungs to remove fluid or mucus. Some two-channeled catheters are used to induce a chemical into an organ and remove the organs contents at the same time. Others can be used for wound drainage or for measuring blood pressure in any of the hearts four chambers. Most intravenous devices (IVs) have very thin catheters that remain in the blood vessel to deliver the intended medication or nutrition. As the body temperature warms these catheters, they become very soft and flexible for patient comfort.
Often, sterile catheters are imbedded or treated with antibacterial substances to minimize infection once they are inserted into the body.
See also Surgery.
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"Catheters." The Gale Encyclopedia of Science. . 21 Sep. 2018 <>.
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Fern test
From Wikipedia, the free encyclopedia
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Positive Fern test
Fern test refers to detection of a characteristic 'fern like' pattern of cervical mucus when a specimen of cervical mucus is allowed to dry on a glass slide and is viewed under a low-power microscope. The fern test is used to provide evidence of the presence of amniotic fluid and is used in obstetrics to detect the rupture of membranes and the onset of labor. It also may provide indirect evidence of ovulation and fertility, although it does not predict the time of ovulation.
Ferning occurs due to the presence of sodium chloride in mucus under estrogen effect. When high levels of estrogen are present, just before ovulation, the cervical mucus forms fern-like patterns due to crystallization of sodium chloride on mucus fibers. This pattern is known as arborization or 'ferning'.1
When progesterone is the dominant hormone, as it would be in the second half of a normal cycle, the fern pattern is no longer discernible, and the pattern is completely absent by the 22nd day of a woman's cycle. The disappearance of the fern pattern after the 22nd day suggests ovulation, and its persistence throughout the menstrual cycle suggests an-ovulation (infertility).[1]
1. ^ Patrick Duff, MD (2016). Preterm premature (prelabor) rupture of membranes. In Vanessa A Barss, MD, FACOG (Ed.), uptodate Retrieved from http://www.uptodate.com/'
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A Brief History of Time | Study Guide
Stephen Hawking
Download a PDF to print or study offline.
Study Guide
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How to Cite This Study Guide
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Course Hero. "A Brief History of Time Study Guide." Course Hero. 3 Nov. 2017. Web. 21 Sep. 2018. <https://www.coursehero.com/lit/A-Brief-History-of-Time/>.
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Course Hero. (2017, November 3). A Brief History of Time Study Guide. In Course Hero. Retrieved September 21, 2018, from https://www.coursehero.com/lit/A-Brief-History-of-Time/
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Course Hero. "A Brief History of Time Study Guide." November 3, 2017. Accessed September 21, 2018. https://www.coursehero.com/lit/A-Brief-History-of-Time/.
Course Hero, "A Brief History of Time Study Guide," November 3, 2017, accessed September 21, 2018, https://www.coursehero.com/lit/A-Brief-History-of-Time/.
A Brief History of Time | Chapter 3 : The Expanding Universe | Summary
Stephen Hawking points out in this chapter that humans have been aware of the Milky Way and other visible celestial features since ancient times. However, our understanding of these bodies was slow in coming. It wasn't until 1750 when observations indicated that the band of stars in the sky was one branch of a disk-shaped cluster of stars, and the objects in orbit around them, a galaxy. Sir William Herschel later made a detailed survey of visible stars that agreed with this model. However, the picture of our solar system as one of many in a great cluster of stars revolving around a spinning center caught on only in the early 20th century. The concept of a wider universe gained greater acceptance in 1924, when Edwin Hubble went on to demonstrate that ours was only one of many galaxies.
In the 1920s both nearby and distant stars were studied. Types of stars and galaxies can be told apart from one another by charting their light spectra (bands of colors in the light they emit, just as a rainbow represents the band of all visible light from violet to red). By measuring the relative brightness of these distant objects, their thermal (or temperature) spectra can also be determined. But astronomers found the spectra of very distant objects confusing—the spectra were so strange the stars seemed to be composed of elements never observed on Earth—until astronomers recognized familiar patterns and shifted the spectra toward the red end of the scale (called a red shift). Because the spectral lines were simply uniformly out of place (for example, as if we found all of the buildings in a major city shifted 50 miles south with the entire grid of roads left in place), the shifted spectra showed compositions similar to stars in our own galaxy.
The only available explanation for this red shift has been that these objects are all moving away from us at a rapid rate, suggesting that the universe itself is expanding. Furthermore, it appeared to be expanding at the same rate in all directions, an effect verified in the 1960s by measurements of microwave radiation. In a case of situational irony, both Sir Isaac Newton's theory of gravity and Albert Einstein's theory of relativity could predict an expanding universe, but in both cases the idea was dismissed as being attributed to flaws in the models.
The idea that the universe is expanding suggests (as Hawking explains it) that in the past, all the objects that are moving away from each other now must once have been much closer together. The implication is, according to Hawking, that the universe had a beginning and may have an end at some future time. These suppositions were supported by Russian mathematician Alexander Friedmann, who predicted in 1922 that Hubble's observations would be correct, taking into account two fundamental assumptions. One assumption was that the universe looks the same in every direction around us (in accounting for very distant objects). The other assumption was that the expansion of the universe would look the same when viewed from any galaxy other than our own.
These two assumptions led to three Friedmann models of origin-to-end for the universe. One model describes an arc by which, at a given point of expansion, the entire process reverses until all matter converges at the end, the so-called big crunch. Hawking explains it as one in which "space is bent in on itself, like the surface of the earth." The second model states that the expansion continues indefinitely, "bending space the other way like the surface of a saddle." The third model shows that with a balanced rate of expansion, space is infinitely flat.
Hawking continues with his own entry into the study of the big bang theory, which was built on the work of Roger Penrose. Penrose's work showed that a collapsing star can create a singularity. Hawking took Penrose's model and reversed the time, proposing it as a model for how a beginning—the big bang—might have happened. Penrose and Hawking jointly released a paper in 1970, arguing and convincing many that the big bang theory is true. However, Hawking has since changed his position and argues that no singularity existed at the big bang. He argues that quantum mechanics, or the behavior of subatomic particles, can offer a different explanation.
This chapter traces how the popular and scientific conceptions of the universe have changed, particularly during the 20th century. It is notable that even scientists have been reluctant to accept radical changes. One may see this reticence as commendable, reflecting professional skepticism of a scientist. On the other hand, one could also see it as a sort of professional self-defense—trying not to attract criticism for what initially seemed like outlandish predictions.
This chapter also highlights the fact that whether a model is accepted rejected sometimes depends on political and religious matters more than on science. For example, whereas many scientists resisted the big bang theory in part because it smacked of divine intervention, the Roman Catholic Church accepted the theory precisely because they saw it as in accordance with scripture. Similarly, the Penrose–Hawking singularity-based model for the big bang met with resistance because of both political and aesthetic reasons.
Another interesting tidbit in this chapter is found in the section where Hawking refers to his own PhD thesis. Had his ALS progressed more quickly, he might not have continued his studies. But as it was, two years after his diagnosis, Hawking was still feeling relatively well and looking to marry, so he had ample personal motivations to continue his studies and start a career as a researcher.
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Hemagglutinins: Agents that cause agglutination of red blood cells. They include antibodies, blood group antigens, lectins, autoimmune factors, bacterial, viral, or parasitic blood agglutinins, etc.Hemagglutinins, Viral: Specific hemagglutinin subtypes encoded by VIRUSES.Hemagglutinin Glycoproteins, Influenza Virus: Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.Influenza A virus: The type species of the genus INFLUENZAVIRUS A that causes influenza and other diseases in humans and animals. Antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. Transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). Infected birds shed the virus in their saliva, nasal secretions, and feces.Orthomyxoviridae: A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.Neuraminidase: An enzyme that catalyzes the hydrolysis of alpha-2,3, alpha-2,6-, and alpha-2,8-glycosidic linkages (at a decreasing rate, respectively) of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid, and synthetic substrate. (From Enzyme Nomenclature, 1992)Hemagglutination Inhibition Tests: Serologic tests in which a known quantity of antigen is added to the serum prior to the addition of a red cell suspension. Reaction result is expressed as the smallest amount of antigen which causes complete inhibition of hemagglutination.Influenza A Virus, H5N1 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 1. The H5N1 subtype, frequently referred to as the bird flu virus, is endemic in wild birds and very contagious among both domestic (POULTRY) and wild birds. It does not usually infect humans, but some cases have been reported.Orthomyxoviridae Infections: Virus diseases caused by the ORTHOMYXOVIRIDAE.Influenza Vaccines: Vaccines used to prevent infection by viruses in the family ORTHOMYXOVIRIDAE. It includes both killed and attenuated vaccines. The composition of the vaccines is changed each year in response to antigenic shifts and changes in prevalence of influenza virus strains. The vaccine is usually bivalent or trivalent, containing one or two INFLUENZAVIRUS A strains and one INFLUENZAVIRUS B strain.Hemagglutination: The aggregation of ERYTHROCYTES by AGGLUTININS, including antibodies, lectins, and viral proteins (HEMAGGLUTINATION, VIRAL).Influenza A Virus, H3N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 2. The H3N2 subtype was responsible for the Hong Kong flu pandemic of 1968.Influenza, Human: An acute viral infection in humans involving the respiratory tract. It is marked by inflammation of the NASAL MUCOSA; the PHARYNX; and conjunctiva, and by headache and severe, often generalized, myalgia.Influenza in Birds: Infection of domestic and wild fowl and other BIRDS with INFLUENZA A VIRUS. Avian influenza usually does not sicken birds, but can be highly pathogenic and fatal in domestic POULTRY.Hemagglutination Tests: Sensitive tests to measure certain antigens, antibodies, or viruses, using their ability to agglutinate certain erythrocytes. (From Stedman, 26th ed)Measles virus: The type species of MORBILLIVIRUS and the cause of the highly infectious human disease MEASLES, which affects mostly children.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Influenza A Virus, H1N1 Subtype: A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 1 and neuraminidase 1. The H1N1 subtype was responsible for the Spanish flu pandemic of 1918.Hemagglutination, Viral: Agglutination of ERYTHROCYTES by a virus.Bromelains: Protein-digesting and milk-clotting enzymes found in PINEAPPLE fruit juice and stem tissue. Enzymes from the two sources are distinguished as fruit bromelain and stem bromelain. This enzyme was formerly listed as EC Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.Ferrets: Semidomesticated variety of European polecat much used for hunting RODENTS and/or RABBITS and as a laboratory animal. It is in the subfamily Mustelinae, family MUSTELIDAE.Agglutinins: Substances, usually of biological origin, that cause cells or other organic particles to aggregate and stick to each other. They include those ANTIBODIES which cause aggregation or agglutination of particulate or insoluble ANTIGENS.Membrane Fusion: The adherence and merging of cell membranes, intracellular membranes, or artificial membranes to each other or to viruses, parasites, or interstitial particles through a variety of chemical and physical processes.Influenza B virus: Species of the genus INFLUENZAVIRUS B that cause HUMAN INFLUENZA and other diseases primarily in humans. Antigenic variation is less extensive than in type A viruses (INFLUENZA A VIRUS) and consequently there is no basis for distinct subtypes or variants. Epidemics are less likely than with INFLUENZA A VIRUS and there have been no pandemics. Previously only found in humans, Influenza B virus has been isolated from seals which may constitute the animal reservoir from which humans are exposed.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Hemadsorption: A phenomenon manifested by an agent or substance adhering to or being adsorbed on the surface of a red blood cell, as tuberculin can be adsorbed on red blood cells under certain conditions. (Stedman, 25th ed)Viral Fusion Proteins: Proteins, usually glycoproteins, found in the viral envelopes of a variety of viruses. They promote cell membrane fusion and thereby may function in the uptake of the virus by cells.Reassortant Viruses: Viruses containing two or more pieces of nucleic acid (segmented genome) from different parents. Such viruses are produced in cells coinfected with different strains of a given virus.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Influenza A Virus, H2N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 2 and neuraminidase 2. The H2N2 subtype was responsible for the Asian flu pandemic of 1957.Birds: Warm-blooded VERTEBRATES possessing FEATHERS and belonging to the class Aves.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Madin Darby Canine Kidney Cells: An epithelial cell line derived from a kidney of a normal adult female dog.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.Epitopes: Sites on an antigen that interact with specific antibodies.Influenza A Virus, H9N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 9 and neuraminidase 2. The H9N2 subtype usually infects domestic birds (POULTRY) but there have been some human infections reported.Chickens: Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.N-Acetylneuraminic Acid: An N-acyl derivative of neuraminic acid. N-acetylneuraminic acid occurs in many polysaccharides, glycoproteins, and glycolipids in animals and bacteria. (From Dorland, 28th ed, p1518)Cross Reactions: Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.Mice, Inbred BALB CAntibodies, Neutralizing: Antibodies that reduce or abolish some biological activity of a soluble antigen or infectious agent, usually a virus.Influenza A Virus, H7N7 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 7. The H7N7 subtype produced an epidemic in 2003 which was highly pathogenic among domestic birds (POULTRY). Some infections in humans were reported.Antigenic Variation: Change in the surface ANTIGEN of a microorganism. There are two different types. One is a phenomenon, especially associated with INFLUENZA VIRUSES, where they undergo spontaneous variation both as slow antigenic drift and sudden emergence of new strains (antigenic shift). The second type is when certain PARASITES, especially trypanosomes, PLASMODIUM, and BORRELIA, survive the immune response of the host by changing the surface coat (antigen switching). (From Herbert et al., The Dictionary of Immunology, 4th ed)Antigens, CD46: A ubiquitously expressed complement receptor that binds COMPLEMENT C3B and COMPLEMENT C4B and serves as a cofactor for their inactivation. CD46 also interacts with a wide variety of pathogens and mediates immune response.DucksInfluenza A Virus, H3N8 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 3 and neuraminidase 8. The H3N8 subtype has frequently been found in horses.Neutralization Tests: The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).Sialic Acids: A group of naturally occurring N-and O-acyl derivatives of the deoxyamino sugar neuraminic acid. They are ubiquitously distributed in many tissues.Influenza A Virus, H5N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 5 and neuraminidase 2. The H5N2 subtype has been found to be highly pathogenic in chickens.Viral Proteins: Proteins found in any species of virus.Distemper Virus, Canine: A species of MORBILLIVIRUS causing distemper in dogs, wolves, foxes, raccoons, and ferrets. Pinnipeds have also been known to contract Canine distemper virus from contact with domestic dogs.Chick Embryo: The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.Whooping Cough: A respiratory infection caused by BORDETELLA PERTUSSIS and characterized by paroxysmal coughing ending in a prolonged crowing intake of breath.Virulence: The degree of pathogenicity within a group or species of microorganisms or viruses as indicated by case fatality rates and/or the ability of the organism to invade the tissues of the host. The pathogenic capacity of an organism is determined by its VIRULENCE FACTORS.GeeseErythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Glycosylation: The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.Vibrio cholerae: The etiologic agent of CHOLERA.Vaccines, Synthetic: Small synthetic peptides that mimic surface antigens of pathogens and are immunogenic, or vaccines manufactured with the aid of recombinant DNA techniques. The latter vaccines may also be whole viruses whose nucleic acids have been modified.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Measles: A highly contagious infectious disease caused by MORBILLIVIRUS, common among children but also seen in the nonimmune of any age, in which the virus enters the respiratory tract via droplet nuclei and multiplies in the epithelial cells, spreading throughout the MONONUCLEAR PHAGOCYTE SYSTEM.Virulence Factors, Bordetella: A set of BACTERIAL ADHESINS and TOXINS, BIOLOGICAL produced by BORDETELLA organisms that determine the pathogenesis of BORDETELLA INFECTIONS, such as WHOOPING COUGH. They include filamentous hemagglutinin; FIMBRIAE PROTEINS; pertactin; PERTUSSIS TOXIN; ADENYLATE CYCLASE TOXIN; dermonecrotic toxin; tracheal cytotoxin; Bordetella LIPOPOLYSACCHARIDES; and tracheal colonization factor.Virus Attachment: The binding of virus particles to receptors on the host cell surface. For enveloped viruses, the virion ligand is usually a surface glycoprotein as is the cellular receptor. For non-enveloped viruses, the virus CAPSID serves as the ligand.Phylogeny: The relationships of groups of organisms as reflected by their genetic makeup.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Lectins: Proteins that share the common characteristic of binding to carbohydrates. Some ANTIBODIES and carbohydrate-metabolizing proteins (ENZYMES) also bind to carbohydrates, however they are not considered lectins. PLANT LECTINS are carbohydrate-binding proteins that have been primarily identified by their hemagglutinating activity (HEMAGGLUTININS). However, a variety of lectins occur in animal species where they serve diverse array of functions through specific carbohydrate recognition.Cell Fusion: Fusion of somatic cells in vitro or in vivo, which results in somatic cell hybridization.Cross Protection: Protection conferred on a host by inoculation with one strain or component of a microorganism that prevents infection when later challenged with a similar strain. Most commonly the microorganism is a virus.Vaccines, Inactivated: Vaccines in which the infectious microbial nucleic acid components have been destroyed by chemical or physical treatment (e.g., formalin, beta-propiolactone, gamma radiation) without affecting the antigenicity or immunogenicity of the viral coat or bacterial outer membrane proteins.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Amino Acid Substitution: The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.Pandemics: Epidemics of infectious disease that have spread to many countries, often more than one continent, and usually affecting a large number of people.Genes, Viral: The functional hereditary units of VIRUSES.Viral Envelope Proteins: Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.Cercopithecus aethiops: A species of CERCOPITHECUS containing three subspecies: C. tantalus, C. pygerythrus, and C. sabeus. They are found in the forests and savannah of Africa. The African green monkey (C. pygerythrus) is the natural host of SIMIAN IMMUNODEFICIENCY VIRUS and is used in AIDS research.Viral Matrix Proteins: Proteins associated with the inner surface of the lipid bilayer of the viral envelope. These proteins have been implicated in control of viral transcription and may possibly serve as the "glue" that binds the nucleocapsid to the appropriate membrane site during viral budding from the host cell.Poultry: Domesticated birds raised for food. It typically includes CHICKENS; TURKEYS, DUCKS; GEESE; and others.Morbillivirus: A genus of the family PARAMYXOVIRIDAE (subfamily PARAMYXOVIRINAE) where the virions of most members have hemagglutinin but not neuraminidase activity. All members produce both cytoplasmic and intranuclear inclusion bodies. MEASLES VIRUS is the type species.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Fimbriae, Bacterial: Thin, hairlike appendages, 1 to 20 microns in length and often occurring in large numbers, present on the cells of gram-negative bacteria, particularly Enterobacteriaceae and Neisseria. Unlike flagella, they do not possess motility, but being protein (pilin) in nature, they possess antigenic and hemagglutinating properties. They are of medical importance because some fimbriae mediate the attachment of bacteria to cells via adhesins (ADHESINS, BACTERIAL). Bacterial fimbriae refer to common pili, to be distinguished from the preferred use of "pili", which is confined to sex pili (PILI, SEX).Vaccination: Administration of vaccines to stimulate the host's immune response. This includes any preparation intended for active immunological prophylaxis.Influenza A Virus, H7N9 Subtype: A subtype of INFLUENZA A VIRUS with the surface proteins hemagglutinin 7 and neuraminidase 9. This avian origin virus was first identified in humans in 2013.Vaccinia virus: The type species of ORTHOPOXVIRUS, related to COWPOX VIRUS, but whose true origin is unknown. It has been used as a live vaccine against SMALLPOX. It is also used as a vector for inserting foreign DNA into animals. Rabbitpox virus is a subspecies of VACCINIA VIRUS.Antibody Specificity: The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.Porphyromonas gingivalis: A species of gram-negative, anaerobic, rod-shaped bacteria originally classified within the BACTEROIDES genus. This bacterium produces a cell-bound, oxygen-sensitive collagenase and is isolated from the human mouth.Hemolysis: The destruction of ERYTHROCYTES by many different causal agents such as antibodies, bacteria, chemicals, temperature, and changes in tonicity.Vero Cells: A CELL LINE derived from the kidney of the African green (vervet) monkey, (CERCOPITHECUS AETHIOPS) used primarily in virus replication studies and plaque assays.Virus Replication: The process of intracellular viral multiplication, consisting of the synthesis of PROTEINS; NUCLEIC ACIDS; and sometimes LIPIDS, and their assembly into a new infectious particle.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Reverse Genetics: The use of techniques that produce a functional MUTATION or an effect on GENE EXPRESSION of a specific gene of interest in order to identify the role or activity of the gene product of that gene.Rinderpest: A viral disease of cloven-hoofed animals caused by MORBILLIVIRUS. It may be acute, subacute, or chronic with the major lesions characterized by inflammation and ulceration of the entire digestive tract. The disease was declared successfully eradicated worldwide in 2010.Rinderpest virus: A species of MORBILLIVIRUS causing cattle plague, a disease with high mortality. Sheep, goats, pigs, and other animals of the order Artiodactyla can also be infected.Measles Vaccine: A live attenuated virus vaccine of chick embryo origin, used for routine immunization of children and for immunization of adolescents and adults who have not had measles or been immunized with live measles vaccine and have no serum antibodies against measles. Children are usually immunized with measles-mumps-rubella combination vaccine. (From Dorland, 28th ed)Immunization: Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).Distemper: A name for several highly contagious viral diseases of animals, especially canine distemper. In dogs, it is caused by the canine distemper virus (DISTEMPER VIRUS, CANINE). It is characterized by a diphasic fever, leukopenia, gastrointestinal and respiratory inflammation and sometimes, neurologic complications. In cats it is known as FELINE PANLEUKOPENIA.Paramyxoviridae: A family of spherical viruses, of the order MONONEGAVIRALES, somewhat larger than the orthomyxoviruses, and containing single-stranded RNA. Subfamilies include PARAMYXOVIRINAE and PNEUMOVIRINAE.Newcastle disease virus: The most well known avian paramyxovirus in the genus AVULAVIRUS and the cause of a highly infectious pneumoencephalitis in fowl. It is also reported to cause CONJUNCTIVITIS in humans. Transmission is by droplet inhalation or ingestion of contaminated water or food.Virus Internalization: The entering of cells by viruses following VIRUS ATTACHMENT. This is achieved by ENDOCYTOSIS, by direct MEMBRANE FUSION of the viral membrane with the CELL MEMBRANE, or by translocation of the whole virus across the cell membrane.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Host Specificity: The properties of a pathogen that makes it capable of infecting one or more specific hosts. The pathogen can include PARASITES as well as VIRUSES; BACTERIA; FUNGI; or PLANTS.Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Immune Sera: Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Influenza A Virus, H7N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 7 and neuraminidase 2. It has been involved in a number of outbreaks in the 21st century on poultry farms and has been isolated a few times in humans.Zanamivir: A guanido-neuraminic acid that is used to inhibit NEURAMINIDASE.Virus Cultivation: Process of growing viruses in live animals, plants, or cultured cells.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Nucleoproteins: Proteins conjugated with nucleic acids.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Mannose: A hexose or fermentable monosaccharide and isomer of glucose from manna, the ash Fraxinus ornus and related plants. (From Grant & Hackh's Chemical Dictionary, 5th ed & Random House Unabridged Dictionary, 2d ed)Vaccines, Attenuated: Live vaccines prepared from microorganisms which have undergone physical adaptation (e.g., by radiation or temperature conditioning) or serial passage in laboratory animal hosts or infected tissue/cell cultures, in order to produce avirulent mutant strains capable of inducing protective immunity.Antibody Formation: The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.Bordetella bronchiseptica: A species of BORDETELLA that is parasitic and pathogenic. It is found in the respiratory tract of domestic and wild mammalian animals and can be transmitted from animals to man. It is a common cause of bronchopneumonia in lower animals.Poultry Diseases: Diseases of birds which are raised as a source of meat or eggs for human consumption and are usually found in barnyards, hatcheries, etc. The concept is differentiated from BIRD DISEASES which is for diseases of birds not considered poultry and usually found in zoos, parks, and the wild.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Mycoplasma synoviae: A species of gram-negative bacteria pathogenic to CHICKENS; TURKEYS, and guinea fowls. It causes disease in a wide variety of organs and tissues including JOINTS, tendon sheaths and the RESPIRATORY TRACT.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.RNA, Viral: Ribonucleic acid that makes up the genetic material of viruses.Agglutination: The clumping together of suspended material resulting from the action of AGGLUTININS.Epitope Mapping: Methods used for studying the interactions of antibodies with specific regions of protein antigens. Important applications of epitope mapping are found within the area of immunochemistry.Administration, Intranasal: Delivery of medications through the nasal mucosa.Serial Passage: Inoculation of a series of animals or in vitro tissue with an infectious bacterium or virus, as in VIRULENCE studies and the development of vaccines.Virus Shedding: The expelling of virus particles from the body. Important routes include the respiratory tract, genital tract, and intestinal tract. Virus shedding is an important means of vertical transmission (INFECTIOUS DISEASE TRANSMISSION, VERTICAL).Trypsin: A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC, DNA: Recombinant DNA vectors encoding antigens administered for the prevention or treatment of disease. The host cells take up the DNA, express the antigen, and present it to the immune system in a manner similar to that which would occur during natural infection. This induces humoral and cellular immune responses against the encoded antigens. The vector is called naked DNA because there is no need for complex formulations or delivery agents; the plasmid is injected in saline or other buffers.Recombination, Genetic: Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.PyransViral Plaque Assay: Method for measuring viral infectivity and multiplication in CULTURED CELLS. Clear lysed areas or plaques develop as the VIRAL PARTICLES are released from the infected cells during incubation. With some VIRUSES, the cells are killed by a cytopathic effect; with others, the infected cells are not killed but can be detected by their hemadsorptive ability. Sometimes the plaque cells contain VIRAL ANTIGENS which can be measured by IMMUNOFLUORESCENCE.Adhesins, Escherichia coli: Thin, filamentous protein structures, including proteinaceous capsular antigens (fimbrial antigens), that mediate adhesion of E. coli to surfaces and play a role in pathogenesis. They have a high affinity for various epithelial cells.Sf9 Cells: Cell line derived from SF21 CELLS which are a cell line isolated from primary explants of SPODOPTERA FRUGIPERDA pupal tissue.Disease Outbreaks: Sudden increase in the incidence of a disease. The concept includes EPIDEMICS and PANDEMICS.Oligosaccharides: Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.Swine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).PolysaccharidesAntigens, Bacterial: Substances elaborated by bacteria that have antigenic activity.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Microscopy, Electron: Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Lung: Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Adjuvants, Immunologic: Substances that augment, stimulate, activate, potentiate, or modulate the immune response at either the cellular or humoral level. The classical agents (Freund's adjuvant, BCG, Corynebacterium parvum, et al.) contain bacterial antigens. Some are endogenous (e.g., histamine, interferon, transfer factor, tuftsin, interleukin-1). Their mode of action is either non-specific, resulting in increased immune responsiveness to a wide variety of antigens, or antigen-specific, i.e., affecting a restricted type of immune response to a narrow group of antigens. The therapeutic efficacy of many biological response modifiers is related to their antigen-specific immunoadjuvanticity.Polysorbates: Sorbitan mono-9-octadecanoate poly(oxy-1,2-ethanediyl) derivatives; complex mixtures of polyoxyethylene ethers used as emulsifiers or dispersing agents in pharmaceuticals.Viral Vaccines: Suspensions of attenuated or killed viruses administered for the prevention or treatment of infectious viral disease.Liposomes: Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.Vaccines, Virosome: Vaccines using VIROSOMES as the antigen delivery system that stimulates the desired immune response.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Protein Processing, Post-Translational: Any of various enzymatically catalyzed post-translational modifications of PEPTIDES or PROTEINS in the cell of origin. These modifications include carboxylation; HYDROXYLATION; ACETYLATION; PHOSPHORYLATION; METHYLATION; GLYCOSYLATION; ubiquitination; oxidation; proteolysis; and crosslinking and result in changes in molecular weight and electrophoretic motility.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Clostridium botulinum: A species of anaerobic, gram-positive, rod-shaped bacteria in the family Clostridiaceae that produces proteins with characteristic neurotoxicity. It is the etiologic agent of BOTULISM in humans, wild fowl, HORSES; and CATTLE. Seven subtypes (sometimes called antigenic types, or strains) exist, each producing a different botulinum toxin (BOTULINUM TOXINS). The organism and its spores are widely distributed in nature.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Amantadine: An antiviral that is used in the prophylactic or symptomatic treatment of influenza A. It is also used as an antiparkinsonian agent, to treat extrapyramidal reactions, and for postherpetic neuralgia. The mechanisms of its effects in movement disorders are not well understood but probably reflect an increase in synthesis and release of dopamine, with perhaps some inhibition of dopamine uptake.Cloaca: A dilated cavity extended caudally from the hindgut. In adult birds, reptiles, amphibians, and many fishes but few mammals, cloaca is a common chamber into which the digestive, urinary and reproductive tracts discharge their contents. In most mammals, cloaca gives rise to LARGE INTESTINE; URINARY BLADDER; and GENITALIA.Virion: The infective system of a virus, composed of the viral genome, a protein core, and a protein coat called a capsid, which may be naked or enclosed in a lipoprotein envelope called the peplos.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Bacterial Proteins: Proteins found in any species of bacterium.Respirovirus: A genus of the family PARAMYXOVIRIDAE (subfamily PARAMYXOVIRINAE) where all the virions have both HEMAGGLUTININ and NEURAMINIDASE activities and encode a non-structural C protein. SENDAI VIRUS is the type species.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Bordetella Infections: Infections with bacteria of the genus BORDETELLA.Genetic Variation: Genotypic differences observed among individuals in a population.Immunization, Secondary: Any immunization following a primary immunization and involving exposure to the same or a closely related antigen.Immunoglobulin A: Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) is the main immunoglobulin in secretions.Injections, Intramuscular: Forceful administration into a muscle of liquid medication, nutrient, or other fluid through a hollow needle piercing the muscle and any tissue covering it.Swine Diseases: Diseases of domestic swine and of the wild boar of the genus Sus.HN Protein: Glycoprotein from Sendai, para-influenza, Newcastle Disease, and other viruses that participates in binding the virus to cell-surface receptors. The HN protein possesses both hemagglutinin and neuraminidase activity.Influenza A Virus, H1N2 Subtype: A subtype of INFLUENZA A VIRUS comprised of the surface proteins hemagglutinin 1 and neuraminidase 2. It is endemic in both human and pig populations.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Oseltamivir: An acetamido cyclohexene that is a structural homolog of SIALIC ACID and inhibits NEURAMINIDASE.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Mutagenesis, Site-Directed: Genetically engineered MUTAGENESIS at a specific site in the DNA molecule that introduces a base substitution, or an insertion or deletion.Bacteroidaceae Infections: Infections with bacteria of the family BACTEROIDACEAE.Biological Transport: The movement of materials (including biochemical substances and drugs) through a biological system at the cellular level. The transport can be across cell membranes and epithelial layers. It also can occur within intracellular compartments and extracellular compartments.Solubility: The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Physarum polycephalum: A protozoan, previously also considered a fungus. Characteristics include sporangia that are stalked and multilobed. It is widely used in biomedical research.Mutation, Missense: A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)Sigmodontinae: A subfamily of the family MURIDAE comprised of 69 genera. New World mice and rats are included in this subfamily.SqualeneAntiviral Agents: Agents used in the prophylaxis or therapy of VIRUS DISEASES. Some of the ways they may act include preventing viral replication by inhibiting viral DNA polymerase; binding to specific cell-surface receptors and inhibiting viral penetration or uncoating; inhibiting viral protein synthesis; or blocking late stages of virus assembly.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Kinetics: The rate dynamics in chemical or physical systems.Immunodiffusion: Technique involving the diffusion of antigen or antibody through a semisolid medium, usually agar or agarose gel, with the result being a precipitin reaction.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Plasmids: Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.Influenzavirus C: A genus of the family ORTHOMYXOVIRIDAE comprising viruses similar to types A and B but less common, more stable, more homogeneous, and lacking the neuraminidase protein. They have not been associated with epidemics but may cause mild influenza. Influenza C virus is the type species.Respiratory System: The tubular and cavernous organs and structures, by means of which pulmonary ventilation and gas exchange between ambient air and the blood are brought about.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Immunization, Passive: Transfer of immunity from immunized to non-immune host by administration of serum antibodies, or transplantation of lymphocytes (ADOPTIVE TRANSFER).Vaccines, Virus-Like Particle: Vaccines using supra-molecular structures composed of multiple copies of recombinantly expressed viral structural proteins. They are often antigentically indistinguishable from the virus from which they were derived.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Centrifugation, Zonal: Centrifugation using a rotating chamber of large capacity in which to separate cell organelles by density-gradient centrifugation. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)DNA, Recombinant: Biologically active DNA which has been formed by the in vitro joining of segments of DNA from different sources. It includes the recombination joint or edge of a heteroduplex region where two recombining DNA molecules are connected.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.
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Create your own at Storyboard That Women Plotting against King and Queen Storming Versailles Breaking into the King's Chambers October 5, 1789, market and fisherwomen were outraged by the increasing and unaffordable prices of bread. Together they formed a mob of thousands of French women to attack the Palaceof Versailles They were supported by the revolutionaries to bring down the King and Queen of France. They stormed the Palace early in the morning and broke down the doors with the weapons they stole from the city armory. It was a vicious and bloodthirsty march, killing anyone who stood in their way of getting to the King and Queen, including putting some guards severed heads on pikes. While they wanted to bring back the King to Paris, they wished death upon the Queen and would have happily killed her there. Contrary to the popular line, "Let them eat cake." The Queen never said anything like that, she probably didn't have enough time to register that they were attacking the Palace before it wastoo late. Marie Antionette ran to her husband's chambers to escape the invaders. There, she and her family were taken to Paris. Do you think they had other reasons for starting the riot? Do you think they were too aggressive? What would have happened if they had killedthe Queen in the King's chambers? Do you think things would have turned out differently?
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Ancient Venus
A land-ocean pattern like the one shown in this artist’s conception was used in a climate model to show how storm clouds could have shielded ancient Venus from strong sunlight. (Credit: NASA)
Today Venus is a hellish planet with a crushingly dense atmosphere of carbon dioxide, but billions of years ago, it could have had habitable surface temperatures and a watery ocean.
That’s the conclusion drawn from a fresh round of climate modeling conducted by scientists at NASA’s Goddard Institute for Space Studies in New York. The analysis was published this week in Geophysical Research Letters.
The computer modeling wound the clock back on Venus’ climate, using calculations similar to those employed to wind the clock forward for our own planet’s climate.
“Many of the same tools we use to model climate change on Earth can be adapted to study climates on other planets, both past and present,” lead study author Michael Way, a researcher at the Goddard Institute, said in a NASA news release. “These results show ancient Venus may have been a very different place than it is today.”
Thanks to a runaway greenhouse effect, Venus’ current surface temperatures can reach 864 degrees Fahrenheit. The planet is covered with thick clouds of sulfuric acid, and the robotic probes that made it to the surface have lasted for only a couple of hours at the most.
Venus is just a little bit smaller than Earth, but orbits closer to the sun and thus receives significantly more sunlight. It also rotates far more slowly: One day on Venus lasts 117 Earth days.
These differences led scientists to assume that Venus lost its surface water to evaporation soon after its formation. The water vapor molecules were broken apart by the sun’s ultraviolet glare, and the hydrogen escaped to space. That resulted in the buildup of carbon dioxide and a stifling greenhouse effect.
Previous climate models assumed that ancient Venus had to have a super-dense atmosphere, like the one it has today, in order to explain its slow rotation rate. But recent research has shown that the atmosphere could once have been as thin as Earth’s.
Way and his colleagues worked that scenario into their updated model. They assumed that Venus’ ancient ocean was not as big as Earth’s – which would slow the progress of the greenhouse effect. They also assumed that the ancient sun was up to 30 percent dimmer than it is today.
All those factors are consistent with scientists’ current understanding of Venus and the solar system. And when the researchers ran the climate modeling software, they found that Venus could have been habitable for up to 2 billion years of its early history before the greenhouse effect took deadly hold.
Venus view
Enhanced imagery from the Venus Express orbiter shows Venus as it is today. (Credit: ESA)
“In the GISS model’s simulation, Venus’ slow spin exposes its dayside to the sun for almost two months at a time,” said study co-author Anthony Del Genio, a climate researcher at the Goddard Institute. “This warms the surface and produces rain that creates a thick layer of clouds, which acts like an umbrella to shield the surface from much of the solar heating. The result is mean climate temperatures that are actually a few degrees cooler than Earth’s today.”
The greenhouse effect eventually caught up with Venus, but the new model suggests that process took more time than previously thought – potentially providing a wider window for life to arise.
It’s unlikely that anything is alive on Venus today. Astrobiologists say the best bet is to look for acid-loving microbes drifting in Venus’ upper atmosphere. In any case, the idea that Venus was once livable brings the planet’s cautionary tale full circle: Back in the 1970s, observations of Venus’ greenhouse effect heightened scientists’ concerns about carbon dioxide emissions here on Earth.
“The surface environment of Venus is a warning,” the late astronomer Carl Sagan wrote. “Something disastrous can happen to a planet rather like our own.”
In addition to Way and Del Genio, the authors of “Was Venus the First Habitable World of Our Solar System?” include Nancy Kiang, Linda Sohl, David Grinspoon, Igor Aleinov, Maxwell Kelley and Thomas Clune.
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Wikipedia open wikipedia design.
Diagram of operant conditioning
In behavioral psychology, reinforcement is a consequence applied that will strengthen an organism's future behavior whenever that behavior is preceded by a specific antecedent stimulus. This strengthening effect may be measured as a higher frequency of behavior (e.g., pulling a lever more frequently), longer duration (e.g., pulling a lever for longer periods of time), greater magnitude (e.g., pulling a lever with greater force), or shorter latency (e.g., pulling a lever more quickly following the antecedent stimulus).
Rewarding stimuli, which are associated with "wanting" and "liking" (desire and pleasure, respectively) and appetitive behavior, function as positive reinforcers;[1] the converse statement is also true: positive reinforcers provide a desirable stimulus.[1] Reinforcement does not require an individual to consciously perceive an effect elicited by the stimulus.[2] Thus, reinforcement occurs only if there is an observable strengthening in behavior. However, there is also negative reinforcement, which is characterized by taking away an undesirable stimulus. An ibuprofen is a negative reinforcer because it takes away pain.
In most cases, the term "reinforcement" refers to an enhancement of behavior, but this term is also sometimes used to denote an enhancement of memory; for example, "post-training reinforcement" refers to the provision of a stimulus (such as food) after a learning session in an attempt to increase the retained breadth, detail, and duration of the individual memories or overall memory just formed.[3] The memory-enhancing stimulus can also be one whose effects are directly rather than only indirectly emotional, as with the phenomenon of "flashbulb memory," in which an emotionally highly intense stimulus can incentivize memory of a set of a situation's circumstances well beyond the subset of those circumstances that caused the emotionally significant stimulus, as when people of appropriate age are able to remember where they were and what they were doing when they learned of the assassination of John F. Kennedy or of the September 11, 2001, terrorist attacks.[4]
Reinforcement is an important part of operant or instrumental conditioning.
Addiction and dependence glossary[5][6][7][8]
• addiction – a brain disorder characterized by compulsive engagement in rewarding stimuli despite adverse consequences
• addictive behavior – a behavior that is both rewarding and reinforcing
• addictive drug – a drug that is both rewarding and reinforcing
• dependence – an adaptive state associated with a withdrawal syndrome upon cessation of repeated exposure to a stimulus (e.g., drug intake)
• drug sensitization or reverse tolerance – the escalating effect of a drug resulting from repeated administration at a given dose
• drug withdrawal – symptoms that occur upon cessation of repeated drug use
• physical dependence – dependence that involves persistent physical–somatic withdrawal symptoms (e.g., fatigue and delirium tremens)
• psychological dependence – dependence that involves emotional–motivational withdrawal symptoms (e.g., dysphoria and anhedonia)
• reinforcing stimuli – stimuli that increase the probability of repeating behaviors paired with them
• rewarding stimuli – stimuli that the brain interprets as intrinsically positive and desirable or as something to approach
• sensitization – an amplified response to a stimulus resulting from repeated exposure to it
• substance use disorder – a condition in which the use of substances leads to clinically and functionally significant impairment or distress
• tolerance – the diminishing effect of a drug resulting from repeated administration at a given dose
Main section: Reinforcement#Operant conditioning
In the behavioral sciences, the terms "positive" and "negative" refer when used in their strict technical sense to the nature of the action performed by the conditioner rather than to the responding operant's evaluation of that action and its consequence(s). "Positive" actions are those that add a factor, be it pleasant or unpleasant, to the environment, whereas "negative" actions are those that remove or withhold from the environment a factor of either type. In turn, the strict sense of "reinforcement" refers only to reward-based conditioning; the introduction of unpleasant factors and the removal or withholding of pleasant factors are instead referred to as "punishment," which when used in its strict sense thus stands in contradistinction to "reinforcement." Thus, "positive reinforcement" refers to the addition of a pleasant factor, "positive punishment" refers to the addition of an unpleasant factor, "negative reinforcement" refers to the removal or withholding of an unpleasant factor, and "negative punishment" refers to the removal or withholding of a pleasant factor.
This usage is at odds with some non-technical usages of the four term combinations, especially in the case of the term "negative reinforcement," which is often used to denote what technical parlance would describe as "positive punishment" in that the non-technical usage interprets "reinforcement" as subsuming both reward and punishment and "negative" as referring to the responding operant's evaluation of the factor being introduced. By contrast, technical parlance would use the term "negative reinforcement" to describe encouragement of a given behavior by creating a scenario in which an unpleasant factor is or will be present but engaging in the behavior results in either escaping from that factor or preventing its occurrence, as in Martin Seligman's experiments involving dogs' learning processes regarding the avoidance of electric shock.
B.F. Skinner was a well-known and influential researcher who articulated many of the theoretical constructs of reinforcement and behaviorism. Skinner defined reinforcers according to the change in response strength (response rate) rather than to more subjective criteria, such as what is pleasurable or valuable to someone. Accordingly, activities, foods or items considered pleasant or enjoyable may not necessarily be reinforcing (because they produce no increase in the response preceding them). Stimuli, settings, and activities only fit the definition of reinforcers if the behavior that immediately precedes the potential reinforcer increases in similar situations in the future; for example, a child who receives a cookie when he or she asks for one. If the frequency of "cookie-requesting behavior" increases, the cookie can be seen as reinforcing "cookie-requesting behavior". If however, "cookie-requesting behavior" does not increase the cookie cannot be considered reinforcing.
The sole criterion that determines if a stimulus is reinforcing is the change in probability of a behavior after administration of that potential reinforcer. Other theories may focus on additional factors such as whether the person expected a behavior to produce a given outcome, but in the behavioral theory, reinforcement is defined by an increased probability of a response.
The study of reinforcement has produced an enormous body of reproducible experimental results. Reinforcement is the central concept and procedure in special education, applied behavior analysis, and the experimental analysis of behavior and is a core concept in some medical and psychopharmacology models, particularly addiction, dependence, and compulsion.
Brief history[edit]
Laboratory research on reinforcement is usually dated from the work of Edward Thorndike, known for his experiments with cats escaping from puzzle boxes.[9] A number of others continued this research, notably B.F. Skinner, who published his seminal work on the topic in The Behavior of Organisms, in 1938, and elaborated this research in many subsequent publications.[10] Notably Skinner argued that positive reinforcement is superior to punishment in shaping behavior.[11] Though punishment may seem just the opposite of reinforcement, Skinner claimed that they differ immensely, saying that positive reinforcement results in lasting behavioral modification (long-term) whereas punishment changes behavior only temporarily (short-term) and has many detrimental side-effects. A great many researchers subsequently expanded our understanding of reinforcement and challenged some of Skinner's conclusions. For example, Azrin and Holz defined punishment as a “consequence of behavior that reduces the future probability of that behavior,”[12] and some studies have shown that positive reinforcement and punishment are equally effective in modifying behavior. Research on the effects of positive reinforcement, negative reinforcement and punishment continue today as those concepts are fundamental to learning theory and apply to many practical applications of that theory.
Operant conditioning[edit]
The term operant conditioning was introduced by B. F. Skinner to indicate that in his experimental paradigm the organism is free to operate on the environment. In this paradigm the experimenter cannot trigger the desirable response; the experimenter waits for the response to occur (to be emitted by the organism) and then a potential reinforcer is delivered. In the classical conditioning paradigm the experimenter triggers (elicits) the desirable response by presenting a reflex eliciting stimulus, the Unconditional Stimulus (UCS), which he pairs (precedes) with a neutral stimulus, the Conditional Stimulus (CS).
Reinforcement is a basic term in operant conditioning. For the punishment aspect of operant conditioning – see punishment (psychology).
Positive reinforcement[edit]
Positive reinforcement occurs when a desirable event or stimulus is presented as a consequence of a behavior and the behavior increases.[13]:253
• Example: Whenever a rat presses a button, it gets a treat. If the rat starts pressing the button more often, the treat serves to positively reinforce this behavior.
• Example: A father gives candy to his daughter when she picks up her toys. If the frequency of picking up the toys increases, the candy is a positive reinforcer (to reinforce the behavior of cleaning up).
• Example: A company enacts a rewards program in which employees earn prizes dependent on the number of items sold. The prizes the employees receive are the positive reinforcement if they increase sales.
Negative reinforcement[edit]
Negative reinforcement occurs when the rate of a behavior increases because an aversive event or stimulus is removed or prevented from happening.[13]:253
• Example: A child cleans their room, and this behavior is followed by the parent stopping "nagging" or asking the child repeatedly to do so. Here, the nagging serves to negatively reinforce the behavior of cleaning because the child wants to remove that aversive stimulus of nagging.
• Example: A person puts ointment on a bug bite to soothe an itch. If the ointment works, the person will likely increase the usage of the ointment because it resulted in removing the itch, which is the negative reinforcer.
• Example: A company has a policy that if an employee completes their assigned work by Friday, they can have Saturday off. Working Saturday is the negative reinforcer, the employee's productivity will be increased as they avoid experiencing the negative reinforcer.
Reinforcement versus punishment[edit]
Reinforcers serve to increase behaviors whereas punishers serve to decrease behaviors; thus, positive reinforcers are stimuli that the subject will work to attain, and negative reinforcers are stimuli that the subject will work to be rid of or to end.[14] The table below illustrates the adding and subtracting of stimuli (pleasant or aversive) in relation to reinforcement vs. punishment.
Rewarding (pleasant) stimulus Aversive (unpleasant) stimulus
Adding/Presenting Positive Reinforcement Positive Punishment
Removing/Taking Away Negative Punishment Negative Reinforcement
Further ideas and concepts[edit]
• Distinguishing between positive and negative can be difficult and may not always be necessary; focusing on what is being removed or added and how it is being removed or added will determine the nature of the reinforcement.
• Negative reinforcement is not punishment. The two, as explained above, differ in the increase (negative reinforcement) or decrease (punishment) of the future probability of a response. In negative reinforcement, the stimulus removed following a response is an aversive stimulus; if this stimulus were presented contingent on a response, it may also function as a positive punisher.
• The form of a stimulus is separate from its function in terms of whether it will reinforce or punish behavior. An event that may punish behavior for some may serve to reinforce behavior for others. Example: A child is repeatedly given detention for acting up in school, but the frequency of the bad behavior increases. Thus, the detention may be a reinforcer (could be positive or negative); perhaps the child now gets one-on-one attention from a teacher or perhaps they now avoid going home where they are often abused.
• Some reinforcement can be simultaneously positive and negative, such as a drug addict taking drugs for the added euphoria (a positive feeling) and eliminating withdrawal symptoms (which would be a negative feeling). Or, in a warm room, a current of external air serves as positive reinforcement because it is pleasantly cool and as negative reinforcement because it removes uncomfortable hot air.
• Reinforcement in the business world is essential in driving productivity. Employees are constantly motivated by the ability to receive a positive stimulus, such as a promotion or a bonus. Employees are also driven by negative reinforcement. This can be seen when employees are offered Saturdays off if they complete the weekly workload by Friday.
• Though negative reinforcement has a positive effect in the short term for a workplace (i.e. encourages a financially beneficial action), over-reliance on a negative reinforcement hinders the ability of workers to act in a creative, engaged way creating growth in the long term.[15]
• Both positive and negative reinforcement increase behavior. Most people, especially children, will learn to follow instruction by a mix of positive and negative reinforcement.[13]
Primary reinforcers[edit]
A primary reinforcer, sometimes called an unconditioned reinforcer, is a stimulus that does not require pairing with a different stimulus in order to function as a reinforcer and most likely has obtained this function through the evolution and its role in species' survival.[16] Examples of primary reinforcers include food, water, and sex. Some primary reinforcers, such as certain drugs, may mimic the effects of other primary reinforcers. While these primary reinforcers are fairly stable through life and across individuals, the reinforcing value of different primary reinforcers varies due to multiple factors (e.g., genetics, experience). Thus, one person may prefer one type of food while another avoids it. Or one person may eat lots of food while another eats very little. So even though food is a primary reinforcer for both individuals, the value of food as a reinforcer differs between them.
Secondary reinforcers[edit]
A secondary reinforcer, sometimes called a conditioned reinforcer, is a stimulus or situation that has acquired its function as a reinforcer after pairing with a stimulus that functions as a reinforcer. This stimulus may be a primary reinforcer or another conditioned reinforcer (such as money). An example of a secondary reinforcer would be the sound from a clicker, as used in clicker training. The sound of the clicker has been associated with praise or treats, and subsequently, the sound of the clicker may function as a reinforcer. Another common example is the sound of people clapping – there is nothing inherently positive about hearing that sound, but we have learned that it is associated with praise and rewards.
When trying to distinguish primary and secondary reinforcers in human examples, use the "caveman test." If the stimulus is something that a caveman would naturally find desirable (e.g., candy) then it is a primary reinforcer. If, on the other hand, the caveman would not react to it (e.g., a dollar bill), it is a secondary reinforcer. As with primary reinforcers, an organism can experience satiation and deprivation with secondary reinforcers.
Other reinforcement terms[edit]
• A generalized reinforcer is a conditioned reinforcer that has obtained the reinforcing function by pairing with many other reinforcers and functions as a reinforcer under a wide-variety of motivating operations. (One example of this is money because it is paired with many other reinforcers).[17]:83
• In reinforcer sampling, a potentially reinforcing but unfamiliar stimulus is presented to an organism without regard to any prior behavior.
• Socially-mediated reinforcement (direct reinforcement) involves the delivery of reinforcement that requires the behavior of another organism.
• The Premack principle is a special case of reinforcement elaborated by David Premack, which states that a highly preferred activity can be used effectively as a reinforcer for a less-preferred activity.[17]:123
• Reinforcement hierarchy is a list of actions, rank-ordering the most desirable to least desirable consequences that may serve as a reinforcer. A reinforcement hierarchy can be used to determine the relative frequency and desirability of different activities, and is often employed when applying the Premack principle.[citation needed]
• Contingent outcomes are more likely to reinforce behavior than non-contingent responses. Contingent outcomes are those directly linked to a causal behavior, such a light turning on being contingent on flipping a switch. Note that contingent outcomes are not necessary to demonstrate reinforcement, but perceived contingency may increase learning.
• Contiguous stimuli are stimuli closely associated by time and space with specific behaviors. They reduce the amount of time needed to learn a behavior while increasing its resistance to extinction. Giving a dog a piece of food immediately after sitting is more contiguous with (and therefore more likely to reinforce) the behavior than a several minute delay in food delivery following the behavior.
• Noncontingent reinforcement refers to response-independent delivery of stimuli identified as reinforcers for some behaviors of that organism. However, this typically entails time-based delivery of stimuli identified as maintaining aberrant behavior, which decreases the rate of the target behavior.[18] As no measured behavior is identified as being strengthened, there is controversy surrounding the use of the term noncontingent "reinforcement".[19]
Natural and artificial[edit]
In his 1967 paper, Arbitrary and Natural Reinforcement, Charles Ferster proposed classifying reinforcement into events that increase frequency of an operant as a natural consequence of the behavior itself, and events that are presumed to affect frequency by their requirement of human mediation, such as in a token economy where subjects are "rewarded" for certain behavior with an arbitrary token of a negotiable value. In 1970, Baer and Wolf created a name for the use of natural reinforcers called "behavior traps".[20] A behavior trap requires only a simple response to enter the trap, yet once entered, the trap cannot be resisted in creating general behavior change. It is the use of a behavioral trap that increases a person's repertoire, by exposing them to the naturally occurring reinforcement of that behavior. Behavior traps have four characteristics:
• They are "baited" with virtually irresistible reinforcers that "lure" the student to the trap
• Only a low-effort response already in the repertoire is necessary to enter the trap
• Interrelated contingencies of reinforcement inside the trap motivate the person to acquire, extend, and maintain targeted academic/social skills[21]
• They can remain effective for long periods of time because the person shows few, if any, satiation effects
As can be seen from the above, artificial reinforcement is in fact created to build or develop skills, and to generalize, it is important that either a behavior trap is introduced to "capture" the skill and utilize naturally occurring reinforcement to maintain or increase it. This behavior trap may simply be a social situation that will generally result from a specific behavior once it has met a certain criterion (e.g., if you use edible reinforcers to train a person to say hello and smile at people when they meet them, after that skill has been built up, the natural reinforcer of other people smiling, and having more friendly interactions will naturally reinforce the skill and the edibles can be faded).[citation needed]
Intermittent reinforcement schedules[edit]
Much behavior is not reinforced every time it is emitted, and the pattern of intermittent reinforcement strongly affects how fast an operant response is learned, what its rate is at any given time, and how long it continues when reinforcement ceases. The simplest rules controlling reinforcement are continuous reinforcement, where every response is reinforced, and extinction, where no response is reinforced. Between these extremes, more complex "schedules of reinforcement" specify the rules that determine how and when a response will be followed by a reinforcer.
Specific schedules of reinforcement reliably induce specific patterns of response, irrespective of the species being investigated (including humans in some conditions). However, the quantitative properties of behavior under a given schedule depend on the parameters of the schedule, and sometimes on other, non-schedule factors. The orderliness and predictability of behavior under schedules of reinforcement was evidence for B.F. Skinner's claim that by using operant conditioning he could obtain "control over behavior", in a way that rendered the theoretical disputes of contemporary comparative psychology obsolete. The reliability of schedule control supported the idea that a radical behaviorist experimental analysis of behavior could be the foundation for a psychology that did not refer to mental or cognitive processes. The reliability of schedules also led to the development of applied behavior analysis as a means of controlling or altering behavior.
Many of the simpler possibilities, and some of the more complex ones, were investigated at great length by Skinner using pigeons, but new schedules continue to be defined and investigated.
Simple schedules[edit]
A chart demonstrating the different response rate of the four simple schedules of reinforcement, each hatch mark designates a reinforcer being given
• Ratio schedule – the reinforcement depends only on the number of responses the organism has performed.
• Continuous reinforcement (CRF) – a schedule of reinforcement in which every occurrence of the instrumental response (desired response) is followed by the reinforcer.[17]:86
• Lab example: each time a rat presses a bar it gets a pellet of food.
• Real-world example: each time a dog defecates outside its owner gives it a treat; each time a person puts $1 in a candy machine and presses the buttons he receives a candy bar.
Simple schedules have a single rule to determine when a single type of reinforcer is delivered for a specific response.
• Fixed ratio (FR) – schedules deliver reinforcement after every nth response.[17]:88 An FR 1 schedule is synonymous with a CRF schedule.
• Example: FR 2 = every second desired response the subject makes is reinforced.
• Lab example: FR 5 = rat's bar-pressing behavior is reinforced with food after every 5 bar-presses in a Skinner box.
• Real-world example: FR 10 = Used car dealer gets a $1000 bonus for each 10 cars sold on the lot.
• Variable ratio schedule (VR) – reinforced on average every nth response, but not always on the nth response.[17]:88
• Lab example: VR 4 = first pellet delivered on 2 bar presses, second pellet delivered on 6 bar presses, third pellet 4 bar presses (2 + 6 + 4 = 12; 12/3= 4 bar presses to receive pellet).
• Real-world example: slot machines (because, though the probability of hitting the jackpot is constant, the number of lever presses needed to hit the jackpot is variable).
• Fixed interval (FI) – reinforced after n amount of time.
• Example: FI 1-s = reinforcement provided for the first response after 1 second.
• Lab example: FI 15-s = rat's bar-pressing behavior is reinforced for the first bar press after 15 seconds passes since the last reinforcement.
• Real-world example: FI 30-min = a 30-minute washing machine cycle.
• Variable interval (VI) – reinforced on an average of n amount of time, but not always exactly n amount of time.[17]:89
• Example: VI 4-min = first pellet delivered after 2 minutes, second delivered after 6 minutes, third is delivered after 4 minutes (2 + 6 + 4 = 12; 12/ 3 = 4). Reinforcement is delivered on the average after 4 minutes.
• Lab example: VI 10-s = a rat's bar-pressing behavior is reinforced for the first bar press after an average of 10 seconds passes since the last reinforcement.
• Real-world example: VI 30-min = Going fishing—you might catch a fish after 10 minutes, then have to wait an hour, then have to wait 20 minutes.
• Fixed time (FT) – Provides a reinforcing stimulus at a fixed time since the last reinforcement delivery, regardless of whether the subject has responded or not. In other words, it is a non-contingent schedule.
• Lab example: FT 5-s = rat gets food every 5 seconds regardless of the behavior.
• Real-world example: FT 30-d = a person gets an annuity check every month regardless of behavior between checks
• Variable time (VT) – Provides reinforcement at an average variable time since last reinforcement, regardless of whether the subject has responded or not.
Simple schedules are utilized in many differential reinforcement[22] procedures:
• Differential reinforcement of alternative behavior (DRA) - A conditioning procedure in which an undesired response is decreased by placing it on extinction or, less commonly, providing contingent punishment, while simultaneously providing reinforcement contingent on a desirable response. An example would be a teacher attending to a student only when they raise their hand, while ignoring the student when he or she calls out.
• Differential reinforcement of other behavior (DRO) – Also known as omission training procedures, an instrumental conditioning procedure in which a positive reinforcer is periodically delivered only if the participant does something other than the target response. An example would be reinforcing any hand action other than nose picking.[17]:338
• Differential reinforcement of incompatible behavior (DRI) – Used to reduce a frequent behavior without punishing it by reinforcing an incompatible response. An example would be reinforcing clapping to reduce nose picking
• Differential reinforcement of low response rate (DRL) – Used to encourage low rates of responding. It is like an interval schedule, except that premature responses reset the time required between behavior.
• Lab example: DRL 10-s = a rat is reinforced for the first response after 10 seconds, but if the rat responds earlier than 10 seconds there is no reinforcement and the rat has to wait 10 seconds from that premature response without another response before bar pressing will lead to reinforcement.
• Real-world example: "If you ask me for a potato chip no more than once every 10 minutes, I will give it to you. If you ask more often, I will give you none."
• Differential reinforcement of high rate (DRH) – Used to increase high rates of responding. It is like an interval schedule, except that a minimum number of responses are required in the interval in order to receive reinforcement.
• Lab example: DRH 10-s/FR 15 = a rat must press a bar 15 times within a 10-second increment to get reinforced.
• Real-world example: "If Lance Armstrong is going to win the Tour de France he has to pedal x number of times during the y-hour race."
Effects of different types of simple schedules[edit]
• Fixed ratio: activity slows after reinforcer is delivered, then response rates increase until the next reinforcer delivery (post-reinforcement pause).
• Variable ratio: rapid, steady rate of responding; most resistant to extinction.
• Fixed interval: responding increases towards the end of the interval; poor resistance to extinction.
• Variable interval: steady activity results, good resistance to extinction.
• Ratio schedules produce higher rates of responding than interval schedules, when the rates of reinforcement are otherwise similar.
• Variable schedules produce higher rates and greater resistance to extinction than most fixed schedules. This is also known as the Partial Reinforcement Extinction Effect (PREE).
• The variable ratio schedule produces both the highest rate of responding and the greatest resistance to extinction (for example, the behavior of gamblers at slot machines).
• Fixed schedules produce "post-reinforcement pauses" (PRP), where responses will briefly cease immediately following reinforcement, though the pause is a function of the upcoming response requirement rather than the prior reinforcement.[23]
• The PRP of a fixed interval schedule is frequently followed by a "scallop-shaped" accelerating rate of response, while fixed ratio schedules produce a more "angular" response.
• fixed interval scallop: the pattern of responding that develops with fixed interval reinforcement schedule, performance on a fixed interval reflects subject's accuracy in telling time.
• Organisms whose schedules of reinforcement are "thinned" (that is, requiring more responses or a greater wait before reinforcement) may experience "ratio strain" if thinned too quickly. This produces behavior similar to that seen during extinction.
• Ratio strain: the disruption of responding that occurs when a fixed ratio response requirement is increased too rapidly.
• Ratio run: high and steady rate of responding that completes each ratio requirement. Usually higher ratio requirement causes longer post-reinforcement pauses to occur.
• Partial reinforcement schedules are more resistant to extinction than continuous reinforcement schedules.
• Ratio schedules are more resistant than interval schedules and variable schedules more resistant than fixed ones.
• Momentary changes in reinforcement value lead to dynamic changes in behavior.[24]
Compound schedules[edit]
Compound schedules combine two or more different simple schedules in some way using the same reinforcer for the same behavior. There are many possibilities; among those most often used are:
• Alternative schedules – A type of compound schedule where two or more simple schedules are in effect and whichever schedule is completed first results in reinforcement.[25]
• Conjunctive schedules – A complex schedule of reinforcement where two or more simple schedules are in effect independently of each other, and requirements on all of the simple schedules must be met for reinforcement.
• Multiple schedules – Two or more schedules alternate over time, with a stimulus indicating which is in force. Reinforcement is delivered if the response requirement is met while a schedule is in effect.
• Example: FR4 when given a whistle and FI6 when given a bell ring.
• Mixed schedules – Either of two, or more, schedules may occur with no stimulus indicating which is in force. Reinforcement is delivered if the response requirement is met while a schedule is in effect.
• Example: FI6 and then VR3 without any stimulus warning of the change in schedule.
• Concurrent schedules – A complex reinforcement procedure in which the participant can choose any one of two or more simple reinforcement schedules that are available simultaneously. Organisms are free to change back and forth between the response alternatives at any time.
• Real-world example: changing channels on a television.
• Concurrent-chain schedule of reinforcement – A complex reinforcement procedure in which the participant is permitted to choose during the first link which of several simple reinforcement schedules will be in effect in the second link. Once a choice has been made, the rejected alternatives become unavailable until the start of the next trial.
• Interlocking schedules – A single schedule with two components where progress in one component affects progress in the other component. In an interlocking FR 60 FI 120-s schedule, for example, each response subtracts time from the interval component such that each response is "equal" to removing two seconds from the FI schedule.
• Chained schedules – Reinforcement occurs after two or more successive schedules have been completed, with a stimulus indicating when one schedule has been completed and the next has started
• Example: On an FR 10 schedule in the presence a red light, a pigeon pecks a green disc 10 times; then, a yellow light indicates an FR 3 schedule is active; after the pigeon pecks a yellow disc 3 times, a green light to indicates a VI 6-s schedule is in effect; if this were the final schedule in the chain, the pigeon would be reinforced for pecking a green disc on a VI 6-s schedule; however, all schedule requirements in the chain must be met before a reinforcer is provided.
• Tandem schedules – Reinforcement occurs when two or more successive schedule requirements have been completed, with no stimulus indicating when a schedule has been completed and the next has started.
• Example: VR 10, after it is completed the schedule is changed without warning to FR 10, after that it is changed without warning to FR 16, etc. At the end of the series of schedules, a reinforcer is finally given.
• Higher-order schedules – completion of one schedule is reinforced according to a second schedule; e.g. in FR2 (FI10 secs), two successive fixed interval schedules require completion before a response is reinforced.
Superimposed schedules[edit]
The psychology term superimposed schedules of reinforcement refers to a structure of rewards where two or more simple schedules of reinforcement operate simultaneously. Reinforcers can be positive, negative, or both. An example is a person who comes home after a long day at work. The behavior of opening the front door is rewarded by a big kiss on the lips by the person's spouse and a rip in the pants from the family dog jumping enthusiastically. Another example of superimposed schedules of reinforcement is a pigeon in an experimental cage pecking at a button. The pecks deliver a hopper of grain every 20th peck, and access to water after every 200 pecks.
Superimposed schedules of reinforcement are a type of compound schedule that evolved from the initial work on simple schedules of reinforcement by B.F. Skinner and his colleagues (Skinner and Ferster, 1957). They demonstrated that reinforcers could be delivered on schedules, and further that organisms behaved differently under different schedules. Rather than a reinforcer, such as food or water, being delivered every time as a consequence of some behavior, a reinforcer could be delivered after more than one instance of the behavior. For example, a pigeon may be required to peck a button switch ten times before food appears. This is a "ratio schedule". Also, a reinforcer could be delivered after an interval of time passed following a target behavior. An example is a rat that is given a food pellet immediately following the first response that occurs after two minutes has elapsed since the last lever press. This is called an "interval schedule".
In addition, ratio schedules can deliver reinforcement following fixed or variable number of behaviors by the individual organism. Likewise, interval schedules can deliver reinforcement following fixed or variable intervals of time following a single response by the organism. Individual behaviors tend to generate response rates that differ based upon how the reinforcement schedule is created. Much subsequent research in many labs examined the effects on behaviors of scheduling reinforcers.
If an organism is offered the opportunity to choose between or among two or more simple schedules of reinforcement at the same time, the reinforcement structure is called a "concurrent schedule of reinforcement". Brechner (1974, 1977) introduced the concept of superimposed schedules of reinforcement in an attempt to create a laboratory analogy of social traps, such as when humans overharvest their fisheries or tear down their rainforests. Brechner created a situation where simple reinforcement schedules were superimposed upon each other. In other words, a single response or group of responses by an organism led to multiple consequences. Concurrent schedules of reinforcement can be thought of as "or" schedules, and superimposed schedules of reinforcement can be thought of as "and" schedules. Brechner and Linder (1981) and Brechner (1987) expanded the concept to describe how superimposed schedules and the social trap analogy could be used to analyze the way energy flows through systems.
Superimposed schedules of reinforcement have many real-world applications in addition to generating social traps. Many different human individual and social situations can be created by superimposing simple reinforcement schedules. For example, a human being could have simultaneous tobacco and alcohol addictions. Even more complex situations can be created or simulated by superimposing two or more concurrent schedules. For example, a high school senior could have a choice between going to Stanford University or UCLA, and at the same time have the choice of going into the Army or the Air Force, and simultaneously the choice of taking a job with an internet company or a job with a software company. That is a reinforcement structure of three superimposed concurrent schedules of reinforcement.
Superimposed schedules of reinforcement can create the three classic conflict situations (approach–approach conflict, approach–avoidance conflict, and avoidance–avoidance conflict) described by Kurt Lewin (1935) and can operationalize other Lewinian situations analyzed by his force field analysis. Other examples of the use of superimposed schedules of reinforcement as an analytical tool are its application to the contingencies of rent control (Brechner, 2003) and problem of toxic waste dumping in the Los Angeles County storm drain system (Brechner, 2010).
Concurrent schedules[edit]
In operant conditioning, concurrent schedules of reinforcement are schedules of reinforcement that are simultaneously available to an animal subject or human participant, so that the subject or participant can respond on either schedule. For example, in a two-alternative forced choice task, a pigeon in a Skinner box is faced with two pecking keys; pecking responses can be made on either, and food reinforcement might follow a peck on either. The schedules of reinforcement arranged for pecks on the two keys can be different. They may be independent, or they may be linked so that behavior on one key affects the likelihood of reinforcement on the other.
It is not necessary for responses on the two schedules to be physically distinct. In an alternate way of arranging concurrent schedules, introduced by Findley in 1958, both schedules are arranged on a single key or other response device, and the subject can respond on a second key to change between the schedules. In such a "Findley concurrent" procedure, a stimulus (e.g., the color of the main key) signals which schedule is in effect.
Concurrent schedules often induce rapid alternation between the keys. To prevent this, a "changeover delay" is commonly introduced: each schedule is inactivated for a brief period after the subject switches to it.
When both the concurrent schedules are variable intervals, a quantitative relationship known as the matching law is found between relative response rates in the two schedules and the relative reinforcement rates they deliver; this was first observed by R.J. Herrnstein in 1961. Matching law is a rule for instrumental behavior which states that the relative rate of responding on a particular response alternative equals the relative rate of reinforcement for that response (rate of behavior = rate of reinforcement). Animals and humans have a tendency to prefer choice in schedules.[26]
Shaping is reinforcement of successive approximations to a desired instrumental response. In training a rat to press a lever, for example, simply turning toward the lever is reinforced at first. Then, only turning and stepping toward it is reinforced. The outcomes of one set of behaviours starts the shaping process for the next set of behaviours, and the outcomes of that set prepares the shaping process for the next set, and so on. As training progresses, the response reinforced becomes progressively more like the desired behavior; each subsequent behaviour becomes a closer approximation of the final behaviour.[27]
Chaining involves linking discrete behaviors together in a series, such that each result of each behavior is both the reinforcement (or consequence) for the previous behavior, and the stimuli (or antecedent) for the next behavior. There are many ways to teach chaining, such as forward chaining (starting from the first behavior in the chain), backwards chaining (starting from the last behavior) and total task chaining (in which the entire behavior is taught from beginning to end, rather than as a series of steps). An example is opening a locked door. First the key is inserted, then turned, then the door opened.
Forward chaining would teach the subject first to insert the key. Once that task is mastered, they are told to insert the key, and taught to turn it. Once that task is mastered, they are told to perform the first two, then taught to open the door. Backwards chaining would involve the teacher first inserting and turning the key, and the subject then being taught to open the door. Once that is learned, the teacher inserts the key, and the subject is taught to turn it, then opens the door as the next step. Finally, the subject is taught to insert the key, and they turn and open the door. Once the first step is mastered, the entire task has been taught. Total task chaining would involve teaching the entire task as a single series, prompting through all steps. Prompts are faded (reduced) at each step as they are mastered.
Persuasive communication and the reinforcement theory[edit]
Persuasive communication
Persuasion influences any person the way they think, act and feel. Persuasive skill tells about how people understand the concern, position and needs of the people. Persuasion can be classified into informal persuasion and formal persuasion.
Informal persuasion
This tells about the way in which a person interacts with colleagues and customers. The informal persuasion can be used in team, memos as well as e-mails.
Formal persuasion
This type of persuasion is used in writing customer letter, proposal and also for formal presentation to any customer or colleagues.
Process of persuasion
Persuasion relates how you influence people with your skills, experience, knowledge, leadership, qualities and team capabilities. Persuasion is an interactive process while getting the work done by others. Here are examples for which you can use persuasion skills in real time. Interview: you can prove your best talents, skills and expertise. Clients: to guide your clients for the achievement of the goals or targets. Memos: to express your ideas and views to coworkers for the improvement in the operations. Resistance identification and positive attitude are the vital roles of persuasion.
Persuasion is a form of human interaction. It takes place when one individual expects some particular response from one or more other individuals and deliberately sets out to secure the response through the use of communication. The communicator must realize that different groups have different values.[28]:24–25
In instrumental learning situations, which involve operant behavior, the persuasive communicator will present his message and then wait for the receiver to make a correct response. As soon as the receiver makes the response, the communicator will attempt to fix the response by some appropriate reward or reinforcement.[29]
In conditional learning situations, where there is respondent behavior, the communicator presents his message so as to elicit the response he wants from the receiver, and the stimulus that originally served to elicit the response then becomes the reinforcing or rewarding element in conditioning.[28]
Mathematical models[edit]
A lot of work has been done in building a mathematical model of reinforcement. This model is known as MPR, short for mathematical principles of reinforcement. Peter Killeen has made key discoveries in the field with his research on pigeons.[30]
The standard definition of behavioral reinforcement has been criticized as circular, since it appears to argue that response strength is increased by reinforcement, and defines reinforcement as something that increases response strength (i.e., response strength is increased by things that increase response strength). However, the correct usage[31] of reinforcement is that something is a reinforcer because of its effect on behavior, and not the other way around. It becomes circular if one says that a particular stimulus strengthens behavior because it is a reinforcer, and does not explain why a stimulus is producing that effect on the behavior. Other definitions have been proposed, such as F.D. Sheffield's "consummatory behavior contingent on a response", but these are not broadly used in psychology.[32]
Increasingly understanding of the role reinforcers play is moving away from a "strengthening" effect to a "signalling" effect.[33] That is, the view that reinforcers increase responding because they signal the behaviours that a likely to result in reinforcement. While in most practical applications, the effect of any given reinforcer will be the same regardless of whether the reinforcer is signalling or strengthening, this approach helps to explain a number of behavioural phenomenon including patterns of responding on intermittent reinforcement schedules (fixed interval scallops) and the differential outcomes effect.[34]
History of the terms[edit]
In the 1920s Russian physiologist Ivan Pavlov may have been the first to use the word reinforcement with respect to behavior, but (according to Dinsmoor) he used its approximate Russian cognate sparingly, and even then it referred to strengthening an already-learned but weakening response. He did not use it, as it is today, for selecting and strengthening new behaviors. Pavlov's introduction of the word extinction (in Russian) approximates today's psychological use.
In popular use, positive reinforcement is often used as a synonym for reward, with people (not behavior) thus being "reinforced", but this is contrary to the term's consistent technical usage, as it is a dimension of behavior, and not the person, which is strengthened. Negative reinforcement is often used by laypeople and even social scientists outside psychology as a synonym for punishment. This is contrary to modern technical use, but it was B.F. Skinner who first used it this way in his 1938 book. By 1953, however, he followed others in thus employing the word punishment, and he re-cast negative reinforcement for the removal of aversive stimuli.
There are some within the field of behavior analysis[35] who have suggested that the terms "positive" and "negative" constitute an unnecessary distinction in discussing reinforcement as it is often unclear whether stimuli are being removed or presented. For example, Iwata poses the question: " a change in temperature more accurately characterized by the presentation of cold (heat) or the removal of heat (cold)?"[36]:363 Thus, reinforcement could be conceptualized as a pre-change condition replaced by a post-change condition that reinforces the behavior that followed the change in stimulus conditions.
Reinforcement and punishment are ubiquitous in human social interactions, and a great many applications of operant principles have been suggested and implemented. Following are a few examples.
Addiction and dependence[edit]
Positive and negative reinforcement play central roles in the development and maintenance of addiction and drug dependence. An addictive drug is intrinsically rewarding; that is, it functions as a primary positive reinforcer of drug use. The brain's reward system assigns it incentive salience (i.e., it is "wanted" or "desired"),[37][38][39] so as an addiction develops, deprivation of the drug leads to craving. In addition, stimuli associated with drug use – e.g., the sight of a syringe, and the location of use – become associated with the intense reinforcement induced by the drug.[37][38][39] These previously neutral stimuli acquire several properties: their appearance can induce craving, and they can become conditioned positive reinforcers of continued use.[37][38][39] Thus, if an addicted individual encounters one of these drug cues, a craving for the associated drug may reappear. For example, anti-drug agencies previously used posters with images of drug paraphernalia as an attempt to show the dangers of drug use. However, such posters are no longer used because of the effects of incentive salience in causing relapse upon sight of the stimuli illustrated in the posters.
In drug dependent individuals, negative reinforcement occurs when a drug is self-administered in order to alleviate or "escape" the symptoms of physical dependence (e.g., tremors and sweating) and/or psychological dependence (e.g., anhedonia, restlessness, irritability, and anxiety) that arise during the state of drug withdrawal.[37]
Animal training[edit]
Animal trainers and pet owners were applying the principles and practices of operant conditioning long before these ideas were named and studied, and animal training still provides one of the clearest and most convincing examples of operant control. Of the concepts and procedures described in this article, a few of the most salient are: availability of immediate reinforcement (e.g. the ever-present bag of dog yummies); contingency, assuring that reinforcement follows the desired behavior and not something else; the use of secondary reinforcement, as in sounding a clicker immediately after a desired response; shaping, as in gradually getting a dog to jump higher and higher; intermittent reinforcement, reducing the frequency of those yummies to induce persistent behavior without satiation; chaining, where a complex behavior is gradually put together.[40]
Child behaviour – parent management training[edit]
Providing positive reinforcement for appropriate child behaviors is a major focus of parent management training. Typically, parents learn to reward appropriate behavior through social rewards (such as praise, smiles, and hugs) as well as concrete rewards (such as stickers or points towards a larger reward as part of an incentive system created collaboratively with the child).[41] In addition, parents learn to select simple behaviors as an initial focus and reward each of the small steps that their child achieves towards reaching a larger goal (this concept is called "successive approximations").[41][42] They may also use indirect rewards such through progress charts. Providing positive reinforcement in the classroom can be beneficial to student success. When applying positive reinforcement to students, it's crucial to make it individualized to that student's needs. This way, the student understands why they are receiving the praise, they can accept it, and eventually learn to continue the action that was earned by positive reinforcement. For example, using rewards or extra recess time might apply to some students more, whereas others might accept the enforcement by receiving stickers or check marks indicating praise.
Both psychologists and economists have become interested in applying operant concepts and findings to the behavior of humans in the marketplace. An example is the analysis of consumer demand, as indexed by the amount of a commodity that is purchased. In economics, the degree to which price influences consumption is called "the price elasticity of demand." Certain commodities are more elastic than others; for example, a change in price of certain foods may have a large effect on the amount bought, while gasoline and other essentials may be less affected by price changes. In terms of operant analysis, such effects may be interpreted in terms of motivations of consumers and the relative value of the commodities as reinforcers.[43]
Gambling – variable ratio scheduling[edit]
As stated earlier in this article, a variable ratio schedule yields reinforcement after the emission of an unpredictable number of responses. This schedule typically generates rapid, persistent responding. Slot machines pay off on a variable ratio schedule, and they produce just this sort of persistent lever-pulling behavior in gamblers. Because the machines are programmed to pay out less money than they take in, the persistent slot-machine user invariably loses in the long run. Slots machines, and thus variable ratio reinforcement, have often been blamed as a factor underlying gambling addiction.[44]
Nudge theory[edit]
Nudge theory (or nudge) is a concept in behavioural science, political theory and economics which argues that positive reinforcement and indirect suggestions to try to achieve non-forced compliance can influence the motives, incentives and decision making of groups and individuals, at least as effectively – if not more effectively – than direct instruction, legislation, or enforcement.
The concept of praise as a means of behavioral reinforcement in humans is rooted in B.F. Skinner's model of operant conditioning. Through this lens, praise has been viewed as a means of positive reinforcement, wherein an observed behavior is made more likely to occur by contingently praising said behavior.[45] Hundreds of studies have demonstrated the effectiveness of praise in promoting positive behaviors, notably in the study of teacher and parent use of praise on child in promoting improved behavior and academic performance,[46][47] but also in the study of work performance.[48] Praise has also been demonstrated to reinforce positive behaviors in non-praised adjacent individuals (such as a classmate of the praise recipient) through vicarious reinforcement.[49] Praise may be more or less effective in changing behavior depending on its form, content and delivery. In order for praise to effect positive behavior change, it must be contingent on the positive behavior (i.e., only administered after the targeted behavior is enacted), must specify the particulars of the behavior that is to be reinforced, and must be delivered sincerely and credibly.[50]
Acknowledging the effect of praise as a positive reinforcement strategy, numerous behavioral and cognitive behavioral interventions have incorporated the use of praise in their protocols.[51][52] The strategic use of praise is recognized as an evidence-based practice in both classroom management[51] and parenting training interventions,[47] though praise is often subsumed in intervention research into a larger category of positive reinforcement, which includes strategies such as strategic attention and behavioral rewards.
Psychological manipulation[edit]
Braiker identified the following ways that manipulators control their victims:[53]
Traumatic bonding[edit]
Traumatic bonding occurs as the result of ongoing cycles of abuse in which the intermittent reinforcement of reward and punishment creates powerful emotional bonds that are resistant to change.[54][55]
Video games[edit]
Most video games are designed around some type of compulsion loop, adding a type of positive reinforcement through a variable rate schedule to keep the player playing the game, though this can also lead to video game addiction.[56]
As part of a trend in the monetization of video games in the 2010s, some games offered "loot boxes" as rewards or purchasable by real-world funds that offered a random selection of in-game items, distributed by rarity. The practice has been tied to the same methods that slot machines and other gambling devices dole out rewards, as it follows a variable rate schedule. While the general perception that loot boxes are a form of gambling, the practice is only classified as such in a few countries as gambling and otherwise legal. However, methods to use those items as virtual currency for online gambling or trading for real-world money has created a skin gambling market that is under legal evaluation.[57]
Workplace culture of fear[edit]
Ashforth discussed potentially destructive sides of leadership and identified what he referred to as petty tyrants: leaders who exercise a tyrannical style of management, resulting in a climate of fear in the workplace.[58] Partial or intermittent negative reinforcement can create an effective climate of fear and doubt.[53] When employees get the sense that bullies are tolerated, a climate of fear may be the result.[59]
Individual differences in sensitivity to reward, punishment, and motivation have been studied under the premises of reinforcement sensitivity theory and have also been applied to workplace performance.
See also[edit]
1. ^ a b Schultz W (July 2015). "Neuronal Reward and Decision Signals: From Theories to Data". Physiological Reviews. 95 (3): 853–951. doi:10.1152/physrev.00023.2014. PMC 4491543. PMID 26109341. Rewards in operant conditioning are positive reinforcers. ... Operant behavior gives a good definition for rewards. Anything that makes an individual come back for more is a positive reinforcer and therefore a reward. Although it provides a good definition, positive reinforcement is only one of several reward functions. ... Rewards are attractive. They are motivating and make us exert an effort. ... Rewards induce approach behavior, also called appetitive or preparatory behavior, and consummatory behavior. ... Thus any stimulus, object, event, activity, or situation that has the potential to make us approach and consume it is by definition a reward. ... Intrinsic rewards are activities that are pleasurable on their own and are undertaken for their own sake, without being the means for getting extrinsic rewards. ... Intrinsic rewards are genuine rewards in their own right, as they induce learning, approach, and pleasure, like perfectioning, playing, and enjoying the piano. Although they can serve to condition higher order rewards, they are not conditioned, higher order rewards, as attaining their reward properties does not require pairing with an unconditioned reward.
2. ^ Winkielman P, Berridge KC, Wilbarger JL (January 2005). "Unconscious affective reactions to masked happy versus angry faces influence consumption behavior and judgments of value". Personality & Social Psychology Bulletin. 31 (1): 121–35. doi:10.1177/0146167204271309. PMID 15574667.
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6. ^ Nestler EJ (December 2013). "Cellular basis of memory for addiction". Dialogues Clin. Neurosci. 15 (4): 431–443. PMC 3898681. PMID 24459410. Despite the importance of numerous psychosocial factors, at its core, drug addiction involves a biological process: the ability of repeated exposure to a drug of abuse to induce changes in a vulnerable brain that drive the compulsive seeking and taking of drugs, and loss of control over drug use, that define a state of addiction. ... A large body of literature has demonstrated that such ΔFosB induction in D1-type [nucleus accumbens] neurons increases an animal's sensitivity to drug as well as natural rewards and promotes drug self-administration, presumably through a process of positive reinforcement ... Another ΔFosB target is cFos: as ΔFosB accumulates with repeated drug exposure it represses c-Fos and contributes to the molecular switch whereby ΔFosB is selectively induced in the chronic drug-treated state.41. ... Moreover, there is increasing evidence that, despite a range of genetic risks for addiction across the population, exposure to sufficiently high doses of a drug for long periods of time can transform someone who has relatively lower genetic loading into an addict.
Addiction: A term used to indicate the most severe, chronic stage of substance-use disorder, in which there is a substantial loss of self-control, as indicated by compulsive drug taking despite the desire to stop taking the drug. In the DSM-5, the term addiction is synonymous with the classification of severe substance-use disorder.
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28. ^ a b Bettinghaus EP (1968). Persuasive Communication. Holt, Rinehart and Winston, Inc.
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31. ^ Skinner BF (1982). Epstein R, ed. Skinner for the classroom : selected papers. Champaign, Ill.: Research Press. ISBN 978-0-87822-261-2.
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34. ^ McCormack J, Arnold-Saritepe A, Elliffe D (June 2017). "The differential outcomes effect in children with autism". Behavioral Interventions. 32 (4): 357–369. doi:10.1002/bin.1489.
35. ^ Michael J (2005). "Positive and negative reinforcement, a distinction that is no longer necessary; or a better way to talk about bad things" (PDF). Journal of Organizational Behavior Management. 24 (1–2): 207–22. doi:10.1300/J075v24n01_15. Archived from the original (PDF) on 9 June 2004.
36. ^ Iwata BA (1987). "Negative reinforcement in applied behavior analysis: an emerging technology". Journal of Applied Behavior Analysis. 20 (4): 361–78. doi:10.1901/jaba.1987.20-361. PMC 1286076. PMID 3323157.
37. ^ a b c d Edwards S (2016). "Reinforcement principles for addiction medicine; from recreational drug use to psychiatric disorder". Progress in Brain Research. 223: 63–76. doi:10.1016/bs.pbr.2015.07.005. PMID 26806771. Abused substances (ranging from alcohol to psychostimulants) are initially ingested at regular occasions according to their positive reinforcing properties. Importantly, repeated exposure to rewarding substances sets off a chain of secondary reinforcing events, whereby cues and contexts associated with drug use may themselves become reinforcing and thereby contribute to the continued use and possible abuse of the substance(s) of choice. ...
An important dimension of reinforcement highly relevant to the addiction process (and particularly relapse) is secondary reinforcement (Stewart, 1992). Secondary reinforcers (in many cases also considered conditioned reinforcers) likely drive the majority of reinforcement processes in humans. In the specific case of drug [addiction], cues and contexts that are intimately and repeatedly associated with drug use will often themselves become reinforcing ... A fundamental piece of Robinson and Berridge's incentive-sensitization theory of addiction posits that the incentive value or attractive nature of such secondary reinforcement processes, in addition to the primary reinforcers themselves, may persist and even become sensitized over time in league with the development of drug addiction (Robinson and Berridge, 1993). ...
Negative reinforcement is a special condition associated with a strengthening of behavioral responses that terminate some ongoing (presumably aversive) stimulus. In this case we can define a negative reinforcer as a motivational stimulus that strengthens such an “escape” response. Historically, in relation to drug addiction, this phenomenon has been consistently observed in humans whereby drugs of abuse are self-administered to quench a motivational need in the state of withdrawal (Wikler, 1952).
38. ^ a b c Berridge KC (April 2012). "From prediction error to incentive salience: mesolimbic computation of reward motivation". The European Journal of Neuroscience. 35 (7): 1124–43. doi:10.1111/j.1460-9568.2012.07990.x. PMC 3325516. PMID 22487042. When a Pavlovian CS+ is attributed with incentive salience it not only triggers ‘wanting’ for its UCS, but often the cue itself becomes highly attractive – even to an irrational degree. This cue attraction is another signature feature of incentive salience. The CS becomes hard not to look at (Wiers & Stacy, 2006; Hickey et al., 2010a; Piech et al., 2010; Anderson et al., 2011). The CS even takes on some incentive properties similar to its UCS. An attractive CS often elicits behavioral motivated approach, and sometimes an individual may even attempt to ‘consume’ the CS somewhat as its UCS (e.g., eat, drink, smoke, have sex with, take as drug). ‘Wanting’ of a CS can turn also turn the formerly neutral stimulus into an instrumental conditioned reinforcer, so that an individual will work to obtain the cue (however, there exist alternative psychological mechanisms for conditioned reinforcement too).
39. ^ a b c Berridge KC, Kringelbach ML (May 2015). "Pleasure systems in the brain". Neuron. 86 (3): 646–64. doi:10.1016/j.neuron.2015.02.018. PMC 4425246. PMID 25950633. An important goal in future for addiction neuroscience is to understand how intense motivation becomes narrowly focused on a particular target. Addiction has been suggested to be partly due to excessive incentive salience produced by sensitized or hyper-reactive dopamine systems that produce intense ‘wanting’ (Robinson and Berridge, 1993). But why one target becomes more ‘wanted’ than all others has not been fully explained. In addicts or agonist-stimulated patients, the repetition of dopamine-stimulation of incentive salience becomes attributed to particular individualized pursuits, such as taking the addictive drug or the particular compulsions. In Pavlovian reward situations, some cues for reward become more ‘wanted’ more than others as powerful motivational magnets, in ways that differ across individuals (Robinson et al., 2014b; Saunders and Robinson, 2013). ... However, hedonic effects might well change over time. As a drug was taken repeatedly, mesolimbic dopaminergic sensitization could consequently occur in susceptible individuals to amplify ‘wanting’ (Leyton and Vezina, 2013; Lodge and Grace, 2011; Wolf and Ferrario, 2010), even if opioid hedonic mechanisms underwent down-regulation due to continual drug stimulation, producing ‘liking’ tolerance. Incentive-sensitization would produce addiction, by selectively magnifying cue-triggered ‘wanting’ to take the drug again, and so powerfully cause motivation even if the drug became less pleasant (Robinson and Berridge, 1993).
40. ^ McGreevy PD, Boakes RA (2007). Carrots and sticks: principles of animal training. Cambridge: Cambridge University Press. ISBN 978-0-521-68691-4.
41. ^ a b Kazdin AE (2010). Problem-solving skills training and parent management training for oppositional defiant disorder and conduct disorder. Evidence-based psychotherapies for children and adolescents (2nd ed.), 211–226. New York: Guilford Press.
42. ^ Forgatch MS, Patterson GR (2010). Parent management training — Oregon model: An intervention for antisocial behavior in children and adolescents. Evidence-based psychotherapies for children and adolescents (2nd ed.), 159–78. New York: Guilford Press.
43. ^ Domjan, M. (2009). The Principles of Learning and Behavior. Wadsworth Publishing Company. 6th Edition. pages 244–249.
44. ^ Lozano Bleda JH, Pérez Nieto MA (November 2012). "Impulsivity, intelligence, and discriminating reinforcement contingencies in a fixed-ratio 3 schedule". The Spanish Journal of Psychology. 15 (3): 922–9. PMID 23156902.
45. ^ Kazdin, Alan (1978). History of behavior modification: Experimental foundations of contemporary research. Baltimore: University Park Press.
46. ^ Baker GL, Barnes HJ (July 1992). "Superior vena cava syndrome: etiology, diagnosis, and treatment". American Journal of Critical Care. 1 (1): 54–64. doi:10.1901/jaba.1983.16-243. PMC 1307879.
47. ^ a b Garland AF, Hawley KM, Brookman-Frazee L, Hurlburt MS (May 2008). "Identifying common elements of evidence-based psychosocial treatments for children's disruptive behavior problems". Journal of the American Academy of Child and Adolescent Psychiatry. 47 (5): 505–14. doi:10.1097/CHI.0b013e31816765c2. PMID 18356768.
48. ^ Crowell CR, Anderson DC, Abel DM, Sergio JP (1988). "Task clarification, performance feedback, and social praise: Procedures for improving the customer service of bank tellers". Journal of Applied Behavior Analysis. 21 (1): 65–71. doi:10.1901/jaba.1988.21-65. PMC 1286094. PMID 16795713.
49. ^ Goldman NC (February 1992). "Adenoid cystic carcinoma of the external auditory canal". Otolaryngology–Head and Neck Surgery. 106 (2): 214–5. doi:10.1901/jaba.1973.6-71. PMC 1310808.
50. ^ Brophy J (1981). "On praising effectively". The Elementary School Journal. 81 (5). JSTOR 1001606.
51. ^ a b Simonsen B, Fairbanks S, Briesch A, Myers D, Sugai G (2008). "Evidence-based Practices in Classroom Management: Considerations for Research to Practice". Education and Treatment of Children. 31 (1): 351–380. doi:10.1353/etc.0.0007.
52. ^ Weisz JR, Kazdin AE (2010). Evidence-based psychotherapies for children and adolescents. Guilford Press.
53. ^ a b Braiker HB (2004). Who's Pulling Your Strings ? How to Break The Cycle of Manipulation. ISBN 0-07-144672-9.
54. ^ Dutton DG, Painter S (1981). "Emotional attachments in abusive relationships: a test of traumatic bonding theory". Violence and Victims. 8 (2): 105–20. PMID 8193053.
55. ^ Sanderson C (2008). Counselling survivors of domestic abuse. London: Jessica Kingsley. p. 84. ISBN 978-1-84642-811-1.
56. ^ Hopson J (27 April 2001). "Behavioral Game Design". Gamasutra.
57. ^ Hood V (October 12, 2017). "Are loot boxes gambling?". Eurogamer. Retrieved October 12, 2017.
58. ^ Ashforth B (1994). "Petty tyranny in organizations". Human Relations. 47 (7): 755–778.
59. ^ Helge H, Sheehan MJ, Cooper CL, Einarsen S (2010). "Organisational Effects of Workplace Bullying". In Einarsen S, Hoel H, Zapf D, Cooper C. Bullying and Harassment in the Workplace: Developments in Theory, Research, and Practice (2nd ed.). Boca Raton, FL: CRC Press. ISBN 978-1-4398-0489-6.
Further reading[edit]
External links[edit]
Images, videos and audio are available under their respective licenses.
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The Hummingbirds of Puerto Rico
The archipelago of Puerto Rico consisting of the main island of Puerto Rico and smaller ones, such as, Mona and Vieques has nine hummingbird species that charm its mountains, forest, countryside, and gardens. Amongst them, the green mango and the Puerto Rican emerald are endemic to the island; whilst the presence of four species is accidental: the green-breasted mango, purple-throated Carib, the ruby-throated hummingbird and the vervain hummingbird. The others, the Antillean Mango, green-throated Carib, and Antillean-crested hummingbird are shared with Hispaniola and the Lesser Antilles.
Puerto Rico has more hummingbird species than any other island of the Greater Antilles (Cuba, Jamaica, and Hispaniola), averaging four, as well as, more than the Lesser Antilles, seven, to the south, excluding Trinidad and Tobago. It has the greater number of native species, inclusive of endemics, five, when compared with the remaining Greater Antilles islands and a comparable number of native species with the Lesser Antilles (the Leeward Islands and the Windward Islands), which has six native species. Also, the number of accidental hummingbird visitors to its shores, four, is greater than the other Greater Antilles territories, one, and the Lesser Antilles, one. However, the Lesser Antilles has a greater number of endemic species, four—possibly due to isolation on a larger number of smaller islands.
Pertaining to their clades, the mangos, large hummingbirds, represent most of Puerto Rico's hummers, five species; they are the Antillean Mango, green-breasted mango, green mango, green-throated Carib, and the purple-throated Carib. There are two species in the emerald clade, the Antillean-crested hummingbird, and Puerto Rican emerald. Lastly, two species compose the 'bees' clades, the ruby-throated hummingbird, and the vervain hummingbird.
The mangos are either endemic, native, or accidental arriving from the Lesser Antilles to the south or in the case of the green-breasted mango, possibly, from South America or Central America. The emeralds are native or endemic to Puerto Rico and the Lesser Antilles. Whilst the bees are accidental to the island arriving from the west, i.e., directly from Hispaniola--in the case of the vervain hummingbird—or from North America, through Jamaica, Cuba, and Hispaniola—in the case of the ruby-throated hummingbird.
Puerto Rico with more hummingbird species than neighbouring islands, whether in total or by residency status, appears to be a convergence zone for hummingbirds in the Caribbean. Its location at the junction of the Caribbean archipelago where the Greater Antilles meets the Lesser Antilles—roughly at an earlier junction of the Caribbean, North American, and the South American tectonic plates—may be a contributing factor. The occurrence of endemism matches the rate found in the other Greater Antilles territories but lower than the rate in the Lesser Antilles. On this island hummingbird species in the mangos clade predominate.
Some leading birding-areas on Puerto Rico are El Yunque (formerly Caribbean National Forest), Humacao National Wildlife Refuge, Cabo Rojo, Guanica State Forest, La Parguera, Maricao State Forest, Toro Negro State Forest, and Fajardo Beach.
Puerto Rican Hummingbirds/caption>
Antillean Crested Hummingbird (Orthorhyncus cristatus)
Length: 8–9.5 cm (3.15–3.7")
Weight: 3.5–4g
Description: a short, straight, black bill and dark-brown eyes; male (♂): glossy-green crown with a green crest tipped metallic-green to blue-green set forward on the head; coal-black malar; glossy green nape; lustrous bronze-green upperparts; coal-black chin and throat; blackish underparts; glossy, bronze-green feathers at front of shoulder; bluish-black flight feathers, and sooty black underwing; dark, bronze-green, central retrices but sooty-black undertail; and blackish legs and feet; female (♀): without the crest on the crown; upperparts are like the male; however, exhibits pale grey underparts; and broad, light-greyish tips on the outer tail retrices; and immature: resembles female with washed yellowish-brown head
Habitat: forest edges, clearings, urban areas, parks, lowlands, and highlands.
Range: the eastern Caribbean, from Puerto Rico, in the north, to the Lesser Antilles, i.e., until Grenada in the South. It is recorded as a vagrant in Florida, USA[1].
Note: O.c. exilis is the subspecies of the Antillean crested hummingbird found on Dominica.
Antillean Mango, a.k.a, Hispaniolan Mango, Dominican Mango or Puerto Rican Golden Hummingbird (Anthracothorax dominicus)
Length: 11–12cm (4.33–4.71")
Weight: 4–8g (.14–.28oz)
Description: a large hummingbird boasting a lengthy, somewhat decurved, black bill; male (♂): lustrous copper green head and generally coppery-green upper parts: nape and back; iridescent-green throat with sometimes with accentuated golden shine; black beneath but with strong suggestions of dark blue on the chest becoming brown nearer the abdomen; dark-purple tail with coppery coverts toward the rump; female (♀): green upperparts with bluish tint; white or greyish underparts and white tips to tail; immature: like the female but the males show a black streak underneath down the middle.
Habitat: subtropical or tropical dry forests, subtropical or tropical moist lowland forests, and secondary forest; observed from sea level to 2,600m[2].
Range: Dominican Republic, Haiti, Puerto Rico, the British Virgin Islands, and U.S. Virgin Islands.
Note: A member of the mangos clade, there have been reported sightings of this species on Inagua island in the Bahamas. The Antillean Mango is also known as the Hispaniolan Mango. Other known local names are Zumbador Grande (Dominican Republic), Zumbador Dorado (Puerto Rico), and Quanga Négresse, Oseau-mouche, and Wange Nègès (Haiti)[3].
Green-breasted Mango, a.k.a. Mango de Prèvost (Anthracothorax prevostii)
Length: 10.2 [4]–12cm (4–4.7")
Weight: ♂ 7.2g (0.3oz), ♀ 6.8g (0.2oz)
Description: a medium to large hummingbird, similar to the black-throated mango, with a black, decurved and somewhat long bill; green upper parts: i.e., greenish crown, nape and back; slender dull-black strip on throat and chest delimited with blue-green; bright yellow-green flanks; dark tail fringed by deep purple-red retrices. female (♀): bronze-green upper parts; white underparts with black stripe on throat that continues as blue-green on the chest; dark tail with broad purple-red and iridescent dark blue bands terminated by white tips on outer retrices; immature: like the female but with a black patch on the abdomen; some grey or beige on head and wings and yellow-brown bordering the belly strip.
Habitat: deciduous forests (to 1,000 m in the upper Cauca River Valley, south-western Colombia[5], glades, orchards, gardens, cultivated areas, savannahs, and pastures.
Range: Bahamas, Belize, Colombia, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, Panama, Peru, Puerto Rico, USA, and Venezuela
Note: This partly migratory species is rare/accidental visitor to Puerto Rico—more than 840km (522mi) from the nearest known breeding populations on northern Venezuela. They occur on some islands off the coast of Central America, in patchworks along the coast of northern South America, and in the USA, e.g., Texas, North Carolina, and Florida, where immature birds account for the majority of sightings. It is a member of the mangos clade.
Green Mango (Anthracothorax viridis)
Length: 11–14cm (4.33–5.5")
Weight: 6.6–7.2gms (0.23–0.25oz)
Description: a large, monomorphic hummingbird; black, shallow-curved bill; polished emerald-green upperparts, i.e., crown, nape, and back; white chin; emerald green throat; bluish-green chest, in general metallic bluish-green underparts; slate grey wings; rounded tail that could be dark or deep, steel-blue; female (♀): like the male; immature: like the adults but with duller underparts or with brown trims to feathers.
Habitat: forests, forest boundary, plantations, and usually on foothills and mountains.
Range: Puerto Rico and affiliated islands
Note: this species is endemic to Puerto Rico and a member of the mangos clade.
Green-throated Carib (Eulampis holosericeus)
Length: 10.5–12cm (3.94–4.72")
Weight: 5–7.8g
Description: a large hummingbird; slightly decurved black bill; metallic green head otherwise metallic bronze-green upperparts; bright green gorget bordered by brilliant metallic blue on chest, depending on lighting; black belly with some green feathering; deep dark blue primaries, may appear greyish brown; green underwing coverts; rounded tail, mostly blue-green upper tail coverts, under tail coverts are metallic blue; dark grey legs; dark grey feet; female (♀): longer and more de-curved bill, duller green upper parts, dark blue tail feathers, in low light the tail looks black; and immature: resembles the female but with bleached brown head.
Habitat: cultivations, deciduous forest, forest, forest undergrowth/shrubbery, gardens, parks, plantations, roadside, secondary forest, and woodlands.
Range: Puerto Rico, Eastern Caribbean, i.e., Lesser Antilles including the Netherlands Antilles (St. Maarten, Saba, and St. Eustatius), and vagrant on Trinidad and Tobago.
Note: The green-throated Carib, a.k.a. green doctor bird, has two subspecies: Eulampis holosericeus and Eulampis chlorolaemus. Eulampis holosericeus ranges from Puerto Rico in the Greater Antilles to the Windward Islands except the island of Grenada. Eulampis chlorolaemus, resident on the island of Grenada, has a darker green throat with a thicker violet-blue delimit at the chest.
Puerto Rican Emerald, a.k.a Zumbadorcito de Puerto Rico (Chlorostilbon maugaeus)
Length: 9–11 (3.5–4.3")
Weight: 2.8–3.6 (.1–.13oz)
Description: a medium sized bird; long, straight, and dark bill; iridescent green upperparts, i.e., crown, nape, back; iridescent green below, i.e., throat, chest and abdomen; and black or dark blue tail; female (♀): white chin with hints of orange; white throat; white breast and outer tail feathers.
Habitat: glades, woodlands, plantations (coffee), mountains, and mangrove swamps.
Range: Puerto Rico
Note: this species is endemic to Puerto Rico. It is found in the northeastern Sierra de Luquillo that encompasses El Yunque National Rainforest, Cordillera Central, and the island's southwestern coast. It is a member of the emeralds clade.
Purple-throated Carib (Eulampis jugularis)
Length: 11–12cm (4.33–4.72")
Weight: male 9–12g, female 7–10g
Description: a tending large hummingbird; long, decurved, black bill; mostly dark overall with suggestions of deep-purple; lustrous, emerald-green wings; deep-purple to dull-purple, iridescent malar, throat, and chest; bluish rump; and greenish-blue tail; female (♀): smaller than the male, longer and tighter curved bill, and has shorter wings; and immature: shorter bills, dispersed brown feathers on upperparts, red flecks on orange throat and chest. Habitat: forest edges, subtropical or tropical moist lowland forests, secondary forests.
Range: Lesser Antilles (eastern Caribbean), from Saba in the north to St. Vincent in the south and as a vagrant in Barbados, Barbuda, Grenada and the Virgin Islands.
Note: the purple-throated carib shows in Brazil as a vagrant[3].
Ruby-throated Hummingbird (Archilochus colubris)
Length: 7–9cm (2.8–3.5")
Weight: 2–6g (0.071-0.21oz.)
Description: straight, slender and long bill, up to 2cm (.79"); a ruby-red gorget, appearing black in some lighting; metallic green above and greyish white below; almost black wings; and a dark forked tail; female (♀): devoid of the gorget, though sometimes sporting a light or whitish throat patch and white tips on a rounded tail.
Range: West Indies, Mexico, Central America, and South America.
Note: The female is slightly larger than the male and has a slightly longer beak. It is a migratory bird that winters in southern Mexico, Central America, South America, and the West Indies. It breeds throughout eastern North America, including the United States and Canada. It is a vagrant species on the islands of Cuba, Hispaniola, and Jamaica.
Vervain Hummingbird (Mellisuga minima)
Length: 6–7cm (2.4–2.76")
Weight: 2–2.4g (0.071–0.085oz.)
Description: Small hummingbird; male and females resemble with minor differences; 0.4 inch (1 cm) dull black bill; dark brown eyes; pale grey chin and throat with impression of grey speckles centrally; dull metallic green upper-parts; pale grey chest also with impressions of grey speckles; metallic green under-parts; darker green, occasionally nearly black, rump and darker green upper tail feathers; dusky coloured legs and feet; female (♀): markedly dark metallic green upper-parts; bluish-green or bronze green, glossy metallic green flanks; and white-tipped outer rectrices (tail feathers) on rounded slightly forked tail; and immature males (♂): resemble adult females, but more speckled grey on throat than female, more defined white-tipped outer rectrices, more intense and widespread glossed green flanks.
Habitat: forest, forest undergrowth/shrubbery, gardens, and secondary forest.
Range: Dominican Republic, Haiti, and Jamaica, and is a vagrant to Puerto Rico.
Note: it is allegedly the second smallest bird in the world after the bee hummingbird, its close cousin of Cuba and Isla de la Juventud. The vervain hummingbirds are faintly larger. Also, allegedly it lays the smallest bird egg; its egg averaging 1cm (0.038") in length and .0375 grams.
Works Cited
1SCHULENBERG, T. S. Antillean Crested Hummingbird (Orthorhyncus cristatus). Neotropical Birds Online. [Online] Cornell Lab of Ornithology, 2010. [Cited: September 19, 2016.]
2SCHULENBERG, T. S. editor. Antillean Mango (Anthracothorax dominicus). In Neotropical Birds Online. [Online] Cornell Lab of Ornithology. [Cited: February 28, 2018.]
3RAFFAELE, Herbert A., et al. Birds of the West Indies (Helm Identification Guides). London: A & C Black, 1998. 0713649054.
4HILTY, Steven L. Birds of Venezuela (2 edition). Princeton: Princeton University Press, 2003. 0691092508.
5HILTY, Steven L, Bill Brown. A Guide to the Birds of Colombia (First Edition). Princeton: Princeton University Press, 1986. 069108372X.
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At the time in New France, most people in the colony were only there temporarily to do business, or to work for a while before returning to France. When Robert Giffard founded the Beauport seigneury in 1634, he became one of the first colonizing seigneurs of New France. The colonists who settled on Giffard’s seigneury were there to start a family and live permanently in the colony. They were not there for the fur trade, which was quite rare at the time.
Relations between the seigneur and the censitaires
A seigneur was someone who ran a large piece of land called a seigneury. On this land, the seigneur was the boss. He gave out parcels of land to the peasants, who in New France were known as the habitants. On a seigneury, these habitants were tenants called censitaires, and paid the seigneur dues called the cens. They also had to acknowledge the seigneur as the most important person of the seigneury.
Author: Alexandre Lanoix
See also – Traces of the past:
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A Brief History of Klezmer Music
by Carl Dimow
The term klezmer originally came from two Hebrew words referring to musical instruments. Over time it came to signify the musicians themselves, and in current usage it also refers to the musical genre - secular Jewish music - which dates back at least as far as the 16th century.
The early klezmorim (plural) played primarily for Jewish weddings though they were also hired for other Jewish and non-Jewish events. Jews lived under a variety of ever changing legal restrictions in Europe which effected when and where the klezmorim could work.
As the Jewish people moved throughout Central and Eastern Europe, the music was influenced by local cultures. There are strong Middle Eastern roots which can also be heard in Jewish litugical music. Other major influences came from Romania, Russia, the Ukraine, and Bessarabia.
Abraham Goldfaden (1840 - 1908) founded the first Yiddish theatre in Romania in the 1870’s. (Yiddish is the secular language of East European Jews.) The Yiddish theatre, both in the old world and in the new, was a major influence in the creation and popularization of Jewish songs. Goldfaden is also known for composing Rozhinkes mit Mandlen (Raisins with Almonds), one of the most popular Jewish ballads.
It was also around this period that the clarinet became the primary lead instrument in klezmer. Previously the violin had been predominant, usually in an ensemble that included flute, drums and hammered dulcimer. Brass instruments were also introduced around the end of the 19th century.
The mass immigration of Jews to the U.S. between 1880 and 1920 coincided with the development of commercial recording technology. Recordings made between 1912 and 1940 for the Jewish public have been the major source material for the current revival of klezmer music. Two immigrant clarinetists in particular, Naftule Brandwein (1889 - 1963) and Dave Tarras (1897 - 198 ), developed unique virtuosic styles which have influenced all subsequent players.
With the assimilation of Jews into mainstream American culture after World War II, klezmer music fell out of favor in the Jewish community. It was only in the 1970’s, as an extension of the folk music revival, that a new group of musicians began to rediscover klezmer music. This lively and soulful music is now more popular than ever, being performed and taken in new directions by bands all over the world.
This material drawn from:
Phillips, Stacy. Klezmer Collection. Pacific, MO.: Mel Bay, 1996.
Sapoznik, Henry. The Compleat Klezmer. Cedarhurst,N.Y.: Tara, 1987.
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Physicists Tie Fluid Into a Knot
| 4 Mar 2013 16:29
The vortex knot was first theorized a century ago, but only created in a lab this year.
Physicists at the University of Chicago have created a vortex knot in a lab environment, a feat which has been theorized for a century but had never been successfully attempted. Creating a vortex knot is, according to a University of Chicago press release, "akin to tying a smoke ring into a knot." Physicists have been puzzled as to why a vortex knot isn't a stable phenomenon, in theory it should be, but in practice they stretch themselves out and break up. The stretching culminates in a reconnection event, where loops elongate, circulate in opposite directions, and then collide. As they collide, parts of the vortices annihilate other parts - unlinking and unknotting the vortex. All of this is sounds very complex, but in reality is a matter of forces smashing into each other and cancelling each other out. The researchers' findings in creating a knot are relevant to many fields, and could lead to advances in turbulence, plasma physics, ordinary fluids, and exotic superfluids - where knots likely appear, but are difficult or impossible to observe.
"We look at plasma physics and turbulence every day in the sun," Study researcher William Irvine said. Those fields have many mysteries, long unsolved, that could be better understood by knowing how a vortex knot works. Plasma flows behave in highly complicated ways, but the electrically charged gas they're composed of behaves and transfer energy much like air in a vortex knot. Additionally, Irvine thinks that "knottedness" is probably a conserved quality - like energy and momentum. "If confirmed, this would deepen our understanding of the dynamics and connections between many disparate fields," Irvine said. "We don't know if its true or not, but I think we can finally test this in experiment. There's actually around 50 years of theory on this subject with no clean experiments.
The experiment was inspired by videos of dolphins blowing air-core vortex rings. Researchers replicated what the dolphins were doing using 3D-printed hydrofoils, and they went through about 30 different shapes before they got the vortices they wanted. The different shapes were captured by a high-speed camera, primarily outlined by bubbles in the water. "The bubles are a great trick because they allow you to see the core of the vortex very clearly," said Irvine. In the future, the team hopes to scale up their research to create larger, more stable rings.
Source & Image: University of Chicago
Comments on
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Armadillidium vulgare
Form and Function
Close of up the armour plating on an Armadillidium vulgare. Photo taken by Dr. Steven Murray, used with permission
The Armadillidium vulgare are earthy colors such as light brown or dark grey in color, in order to blend in with their surroundings (camouflage). They are a member of the phylum arthropoda, which share the synapomorphies of having exoskeletons made of chitin and jointed legs. The exoskeleton provides the organism with protection as well as support and movement because it serves as a site for the muscles to attach to. The exoskeleton of the Armadillidium vulgare is made up of seven overlapping plates (seen in the image above). The plate exoskeleton is made mostly of chitin and it is also supported by calcium carbonate (Seidl, et al. 2012). When the A. vulgare perceive a certain stimulus to be threatening, they curl their bodies into a ball, folding in all 14 of their limbs and antennae, to defend themselves from the threat. This ball form makes it difficult for another organism to pick the A. vulgare up. This inducible defensive (the defense is not present at all times) strategy is called conglobation (Smigel and Gibbs 2008). The A. vulgare may also induce their defense in harsh conditions, such as a very high temperature, to prevent water loss from their bodies (Smigel and Gibbs 2008). Their exoskeletons do not have the waxy cuticle that other insect have so they are very vulnerable to water loss (The Natural Source 1997) which restricts the environments they can inhabit to moist habitats.
They have seven pairs of legs which they use to walk, run, climb and dig (locomotion). This land adaptation differes from many of their water-dwelling relatives who have flipper-like appendages used for swimming (Raham 1986). If an A. vulgare gets flipped onto its back, it has an extremely hard time getting back onto its feet because their backs are so rounded. In order to grow A. vulgare undergo ecdysis (molting) in which they grow a new exoskeleton and shed the old one, similar to the Horseshoe crab and the American lobster who are also members of the phylum Arthropoda. This molting process occurs every few weeks (The Natural Source 1997). They undergo two stages of ecdysis; during the first stage they shed the lower half of the exoskeleton and the upper half during the second stage (American Orchid Society 2003).
The Armadillidium vulgare have compound eyes made up of 15 to 20 eyes (most compound eyes of insects are made up of thousands of small eyes) so they have poor eyesight and require antennae in order to sense their surroundings. They have two pairs of jointed antennae, one large and one small. As the A. vulgare walks it taps the large antennae on the ground in front of it to pick up on smells and find food. The large antennae are also used by the males to find females. The small antennae are called antennules and their function is unknown (Pyers 2005). This species has gills, called pleopods, but are still terrestrial so they need to live in damp habitats in order to keep these gills from drying out. When an A. vulgare is flipped onto its back, two round white organs will be visible. These structures are the pleopods and are made up of pseudotracheae. Air gets trapped within the empty spaces of the pseudotracheae and causes the white color (Raham 1986). If an A. vulgare does dry out it can take up water through a straw-like organ in-between their tails. The water travels up grooves running from the legs up the entire body to the head where the individual can drink it (Raham 1986).
The European A. vulgare has adopted a defensive strategy in which they mimic the colorations of the poisonous black widow spider. This fends off predators that are familiar with the danger that black widow spiders pose because they assume that if the A. vulgare has the same markings, they must be just as dangerous (Raham 1986). This type of mimicry in which a harmless species imitates a harmful one is called batesian mimicry.
Return to Home Discover more on our Reproduction page
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Home > Highlighting JAPAN >Highlighting Japan March 2015>Student's Corner
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Student's Corner
Inamura no Hi
(The Fire of Rice Sheaves)
Long ago there was a village along the shores of Wakayama Prefecture. In this village lived a man in a house on a hill that overlooked the ocean.
One summer’s eve the village held a festival, and the local shrines were filled with people celebrating. Eager to join the festivities, the man changed into his exquisite kimono. As he was changing, however, he suddenly felt the earth shake violently. He remembered words of advice from the village elders: “After a long earthquake comes a tsunami.” He immediately turned to scan the sea below.
He saw the water recoiling fiercely to form a towering wave. “Oh, no! A fearsome tsunami is coming!” he said, quickly setting fire to a torch and rushing toward the shrines where the festival was going on. As he ran, though, he realized he would never be able to make it in time to warn the other villagers. He had an idea: he would set fire to the piles of rice sheaves that had been harvested and use those as a signal.
However, the man knew it wasn’t right to set fire to someone else’s rice sheaves, so he returned to his home and set fire to the ones in his yard instead. The rice sheaves were soon ablaze, and smoke poured forth. The villagers, who had been wrapped up in the festival, suddenly took notice. Thinking a fire had started, they rushed to the scene to put it out. When his fellow villagers arrived, the man yelled, “A tsunami is coming—head for the hills!”
Everyone frantically raced to the shelter of the mountains. Just as they all clambered to safety, a giant tsunami engulfed the village. Fortunately, everyone was spared. From the bottom of their hearts, the villagers thanked the man who had sacrificed his own valuable rice sheaves to protect the village.
The man then worked with the villagers to create a long, tall embankment so that such a thing would never happen again.
The site of the Inamura no Hi story
The tale of “The Fire of Rice Sheaves” is based on the large tsunami that occurred after the Great Ansei Earthquake of 1854. Goryo Hamaguchi, a man from Hirogawa in Wakayama Prefecture, sacrificed his personal properties to save the people of his village.
In 2007, the Inamura-no-Hi no Yakata Hall was built in Hirogawa to pass on the story of his amazing deed and spirit, and the lesson this episode has to tell. Many people visit the site to learn of the dangers of tsunami and deepen their knowledge of how to protect themselves against such a disaster.
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Oral History
Franz Wohlfahrt describes the trial and sentencing of his father
Franz and his family were Jehovah's Witnesses. Germany annexed Austria in 1938. After World War II began, Franz's father was executed because, as a Witness, he opposed war. In 1940, Franz refused to participate in military training and would not salute the Nazi flag. He was imprisoned, interrogated by the Gestapo (German Secret State Police) in Graz, and sentenced to five years of hard labor in a camp in Germany. Franz was liberated by US forces in 1945.
Yes, the first thing was that they called my father for registration in 1939 already, before the Polish war started. And, uh, at that commission, they said, uh, it was visible that my father was a invalid, partly from the First World War. He suffered severely arthritis. He lost all his teeth right in that time. And then they said, uh, he should be left alone and sent back, because he had enough from the First World War. But then there was some question put to him by some of the German officers. And he said that it would be also against his conscience as one of Jehovah's Witnesses to have anything to do with war. And despite that he was not eligible for war service, they kept him there. He was transferred in, uh, military jail. And there, uh, he had to wait about, uh, three months, uh, [to] be transferred from the Vienna army jail to Berlin. And there he was put before the war court, the Reichskriegsgericht, and there, he was sentenced with about 28 other Witnesses to death.
• US Holocaust Memorial Museum Collection
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Wednesday, December 15, 2010
Louis Armstrong
Born in 1901 in New Orleans, the place of birth of jazz, Louis Armstrong was an inventive cornet player, trumpeter and a high-skilled scat singer as well. He came from an impoverished family in Louisiana, the place where he had his first band experiences. In 1922, like many other musicians, he moved to Chicago at the time when the town was the center of jazz universe. From that moment, he never stopped playing. Louis was a hard-worker. He gave an average of 300 performances a year and played in more than 30 films. Armstrong’s nickname was Satchmo (short from Satchelmouth) referring to the way he was blowing in his trumpet. At one moment his mouth was so injured by his own technique that he had to change his way of playing.
Armstrong’s major achievement is that he really helped jazz music to become popular. What was in the beginning a community music played by and for black men, soon became very popular in the whole United States. However, his influence extends well beyond jazz. He was the first to improvise and elaborate on a given melody. His technique has since been copied many times but no one ever reached his virtuosity. He introduced a notion of freedom to music that still has an impact on popular music nowadays.
Even though his involvement in music was very important, he had to face numerous controversies. He was for instance wrongly criticized by civil rights activists in a time of racial segregation because he played as well for whites as for blacks. However, what his critics didn’t know was that he was one of the main financial supports to Martin Luther King. It wasn’t his only way to fight against racism and segregation. However, he always thought music was not to be mixed with political opinions, which explains that he wouldn’t praise his own good actions.
He was indeed a very secret and humble man.
This devotion to the cause of black people and his openness to a white public as well made him a striking symbol of unity in a divided land. His very theatrical character (he was well known for his expressive face and gestures) also played a part in his huge success among the whole population of the United States.
After a long and prosperous career, Louis Armstrong died from a heart attack on July 1971, a month before his 70th birthday. He now lies in Flushing Cemetery in New York City, which still attracts many of his nostalgic fans.
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Home Show Overview Demonstrations Topics Covered Scheduling Info Feedback
Figure I. Figure II. Figure III.
Equipment: Wooden box with dimensions of 26 inches by 26 inches by 15 inches. This box has been custom made with a 10 inch diameter circular hole cut into its side. The back of the box has been removed and replaced with a large neoprene sheet. (See Figure I.)
Smoke generator
Step 1: The smoke generator is used to fill the box with smoke. The demonstrator strikes the back of the box (on the neoprene sheet) with his hand in a quick motion. A large smoke ring goes shooting out the front of the box and travels across the room! (See Figure II. and Figure III.)
Note that cigarette smoke or frozen water vapor from liquid nitrogen can be used if a smoke generator is not available. For health reasons, Phun Physics does not use cigarette smoke during a performance.
Basic Ideas: A stationary object will not move unless it is acted on by an unbalanced force.
Step 1: When the smoke has filled the box, the smoke is more or less motionless. There is little force acting on the particles of smoke. When the demonstrator strikes the back of the box, the neoprene sheet pushes inward. The particles of air and smoke inside the box experience a force from the neoprene sheet, which causes many of the particles to rush out of the box. This rush of air particles causes the smoke ring to travel across the room.
The physics behind aerodynamics is very complex, and to some extent, not fully understood. The basic idea behind the formation of the smoke ring is that the air rushing out the center of the hole is moving faster than the air exiting the hole near the edge. As the air tries to exit the hole near the edge, it is slowed down. This creates a circular motion around the edges of the hole which generates the smoke ring.
More Specifically
Related Topics
The following physics topics are discussed during this demonstration:
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read/write head
Show Summary Details
Quick Reference
A component of a disk drive that records and retrieves data from magnetic disks. Read\write heads are also used sometimes to record and retrieve data from magnetic tapes. In the case of disk drives the assembly consists of a head, sometimes known as a slider, and a mounting arm, known as a flexure. There are two categories of head: those used in floppy drives in which the slider is in contact with the media, and those used in “rigid drives” in which the head flies above the surface of the media. The flying height of the latter depends upon the slider geometry, the flexure loading force, and the rotational speed of the disk.
Subjects: Computing.
Reference entries
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Pearson chemistry book pdf
Pearson Prentice Hall and our other respected imprints provide educational materials, technologies, assessments and related services across the secondary curriculum. Take a closer look at the instructional resources we offer for secondary school classrooms. Use the Web Code pearson chemistry book pdf in your Pearson textbook to access supplementary online resources. The Pearson symbol, or Pearson notation, is used in crystallography as a means of describing a crystal structure, and was originated by W.
The symbol is made up of two letters followed by a number. The lower case letter specifies the crystal family, and the upper case letter the centring type. The number at the end of the Pearson symbol gives the number of the atoms in the unit cell.
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(CANADA, 1851 to 1900 – continued)
home | 18-19th centuries index
CANADA, 1851 to 1900 (6 of 7)
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North-West Rebellion
photo of Louis Riel
Louis Riel, another divinely inspired Métis leader
Battle of Duck Lake
Battle of Duck Lake
Painting of the Battle of Fish Creek
The Battle of Fish Creek, with government forces on the left side of the ravine. Rebels on the right. government forces to strategic withdrawal?
Chief Poundmaker
Poundmaker on his prairie
Gabriel Dumont
Gabriel Dumont
Métis prisoners. Click for link to Wikimedia enlargement and details.
Following their rebellion in 1869-70, many of the blend of Indian and French called Métis left their homes around that area that was to be named Winnipeg, and they moved west. They founded a Catholic community at Batoche on the South Saskatchewan River, and there, in the early 1880s, they again felt harassed by settlers from the east. Also they believed that the Dominion of Canada was not protecting their rights and their survival as a distinct people.
In 1884, the Métis of Batoche asked the leader of their 1870 rebellion, Louis Riel, to return from exile in Montana. Riel remained a hero to them. While in exile he had been elected three times to the Canadian House of Commons but had never returned from exile to assume his seat. The Métis wanted him to appeal to the Canadian government on their behalf. Riel believed that he was their divinely chosen leader and prophet, and he joined them at Batoche.
In March 1885, Riel, Gabriel Dumont and others set up the Provisional Government of Saskatchewan and took control of the area around Batoche. Riel began to contact the local natives: the Cree and Assiniboine. They held in common a dislike of the buffalo having been hunted to extinction by the Hudson's Bay Company and by other hunters. The Cree were displeased by the federal government's occasional violations of treaty terms. And there was hunger among the Métis and Indians.
A group of Métis and Cree men seized the contents of a store at Duck Lake, seven miles northwest of Batoche. There was a confrontation with a police force. The following day another confrontation occurred. On the side of the Métis and Indians were 150 to 200 men. The police numbered about 90. The police suffered 12 dead and 11 wounded. The Métis-Indian side lost six. The police retreated to Fort Carlton a half-mile to the north and quickly again to Prince Albert, 32 miles to the northeast.
Settlers numbering around 500 at the town by Fort Battleford (about 100 miles west of Batoche) heard reports of large numbers of Cree and Assiniboine leaving their reserves and heading their way. They fled to the fort. The Cree chieftain, commonly known as Poundmaker, led a party that arrived there. Oral history describes Poundmaker as wanting to affirm his loyalty to Que, and authorities at the fort refused to talk to Poundmaker. For two days nothing happened. Then, according to reports, the frustrated Indians looted buildings of the nearby abandoned town and withdrew from the area.
Meanwhile, encouraged by what was perceived as a victory for the rebel Métis-Indians at Duck Lake, a Cree named Wandering Spirit led a party to a village by Frog Lake, and there they killed nine white settlers, including two Catholic priests – an incident on April 2 to be known as the Frog Lake Massacre.
Wandering Spirit and his band moved on to Fort Pitt, 167 miles WNW of Batoche. Fort Pitt was defended by a detachment of North-West Mounted Police. Surrounded and outnumbered, on April 15 the garrison commander, Francis Dickens (son of famed novelist Charles Dickens), agreed to negotiate with the Indians. Wandering Spirit let Dickens and others leave. He destroyed the fort and left with some from the fort as hostages. Six days later, Dickens and his men reached Fort Battleford.
A government force of around 900 men from Fort Qu'Appelle in the southeast of Saskatchewan was on its way to Batoche to put down the rebellion. On April 23 they rode into an ambush created by 200 or so Métis and Indian warriors led by the Métis leader Gabriel Dumont. The Métis lost four killed and the Indians lost two. The government force lost 10 dead and 45 wounded. The Métis and Indian force was famished and low on ammunition. They knew they could not hold their positions against a sustained enemy assault, and they withdrew. And the government force also withdrew.
On May 2 a column of Canadian militia and army regulars with a Gatling gun surprised Chief Poundmaker and other Cree at Cut Knife, near Battleford. The Cree were outnumbered and short of ammunition. They lost 3 wounded and 5 dead and the Canadian militia lost 14 wounded and 8 dead. The Cree fled. The Cree who directed the battle, Fine Day, fled to the United States. Poundmaker with starving Indians went to Battleford to make peace with the government, and there he was arrested.
The government force of 900 reached Batoche and began a battle there that was to last to the 12th. The size and firepower of the government force dominated. The Métis ran out of ammunition after three days of battle. Riel surrendered on May 15. Gabriel Dumont and other participants escaped across the border to Montana.
The Métis defeat at Batoche virtually ended the North-West Rebellion. Eight were hanged for their participation in the Frog Lake massacre and other killings. Riel was tried and hanged on November 16. Poundmaker was convicted of treason and sentenced to three years in Stony Mountain Penitentiary.] At his trial, he is reported to have said:
Everything that is bad has been laid against me this summer, there is nothing of it true... Had I wanted war, I would not be here now. I should be on the prairie. You did not catch me. I gave myself up. You have got me because I wanted justice. note83
Poundmaker was released from prison after seven months. Poor health led to his death in 1886.
Gabriel Dumont returned to Batoche in 1893 and was allowed to live out his life there to his death at the age of sixty-eight in 1906.
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Páginas: 2 (345 palabras) Publicado: 22 de septiembre de 2010
The Effect of Environmental Conditions on the Behaviour
of Earthworms and Pill bugs
Background: The way animals behave and evolve is usually altered by the environment that surrounds them. Sincemost organisms cannot change the environment around them, they must position themselves in an environment with favourable conditions. One of the orientation behaviours of an animal is called Taxis. Itis a deliberate movement toward or away from stimulus. Taxis aids animals find a mate, food, or even a safer living environment.
Hypothesis: If the earthworm is placed into a dry environment and thepill bugs into a damp environment, then the earthworm will use Taxis in order to find the damper environment just as the pill bug will use Taxis to find a drier environment.
Variables |Effects of Variable on Experiment |
Independent: The environment | By changing the environment in which the earthworms and pill bugs are located their behaviour will change as well. The change ofbehaviour is due to Taxis which lead the insects to search for the environment in which they are the most comfortable. |
Dependent: The behaviour of the earthworms and pill bugs | The effect of thisvariable on the whole experiment is that through the behaviour change of the insects there will be an answer to the hypothesis. |
Controlled: Temperature, size of environments, amount of worms andpill bugs. | By controlling these variables one can be sure that this is a fair experiment. |
* Earthworms - Water
* Pill bugs
* Container
* Straws
* Tape
*Dry soil
* Damp soil
1. Observe the earthworms and pill bugs. Record the behaviour.
2. Gather all of the materials together.
3. Make a wall of straws by putting themtogether and taping them with the tape.
4. Place the wall of straws in the middle of the container, dividing the container in two.
5. Place dry soil on one side of the container and the damp...
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From Wikipedia, the free encyclopedia
Jump to navigation Jump to search
In recreational mathematics, a repdigit or sometimes monodigit[1] is a natural number composed of repeated instances of the same digit in a positional number system (often implicitly decimal). The word is a portmanteau of repeated and digit.
Examples are 11, 666, 4444, and 999999. All repdigits are palindromic numbers and are multiples of repunits. Two of the most famous repdigits are 666, referred to in Christian Eschatology as the number of the beast, and 777, which is sometimes considered a "lucky number" as it is used on most slot machines to identify a jackpot. Other well-known repdigits include the repunit primes and in particular the Mersenne primes (which are repdigits when represented in binary).
Repdigits are the representation in base of the number where is the repeated digit and is the number of repetitions. For example, the repdigit 77777 in base 10 is .
See also[edit]
1. ^ Beiler, Albert (1966). Recreations in the Theory of Numbers: The Queen of Mathematics Entertains (2 ed.). New York: Dover Publications. p. 83. ISBN 978-0-486-21096-4.
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Monday, March 16, 2015
The Earliest Americans—Ventarrón
In 2007, a temple housing the oldest murals in the Americas, dated to 2000 B.C., was discovered near the town of Ventarrón, Peru. The temple’s unique iconography and clay block construction provide evidence of a previously undocumented civilization—a seminal precursor to complex society in Northern Peru.
Located in a valley, the complex covers about 27,000 square feet, and lies about 12 miles from Sipan, a religious and political center of the later Moche culture, and about 470 miles north of Lima. What may be the oldest documented mural in the Americas has been found inside the 4,000-year-old temple in the Lambayeque region on the northern Peruvian coast. One mural depicts a deer caught in a net, another has an abstract design in red and white that zigzags across one wall.
Part of the red and white abstract uncovered in the Ventarrón structure
Peruvian archaeologist Walter Alva, director of the Royal Tombs of Sipán Museum, and who discovered the looted site, claimed Ventarrón mural and structures predate Sipán by nearly 2,000 years. “The structures were made from primitive materials but were relatively sophisticated and were artistically elaborate,” he added.
Despite the simplicity of the building techniques, dried mud without stone, gravel, or straw filler, the building was decorated with red and white exterior paint and internal rooms contain polychrome murals adjacent to a fire-blackened altar and a ten-foot high chimney—a prominent symbol that leads to the label “fire-temple,” a well known feature of later Andean ceremonial architecture in which people burned offerings to the gods.
The stylized rendering that runs across two full walls of the deer snared in a net runs deep in Andean iconography, being symbolic of the primordial hunt and man’s first offering to the gods. This captured deer image symbol was still being used 2,000 years later by the Moche—no doubt, along with the fire altar and chimney, a continuation of the Ventarrón culture as it progressed over the years into an advanced civilization that archaeologists tend to give a separate cultural designation, but in reality merely suggest one continuing civilization, like that of the Nephites.
His team found the wall paintings after discovering a staircase leading up to a hidden altar, where a second red-and-white wall painting was also found. The stairway caught their attention because it is an architectural oddity in that region. Also strange, the temple was built from blocks of river sediment rather than adobe or stone, which Ignacio Alva Meneses, son of the famed Walter Alva who discovered the tomb of the Lord of Sipán, said were “Construction characteristics that have not been seen before in northern Peru.” The site was built by a culture that predated other pre-Columbian cultures such as the Cupisnique, Chavinoide, Chavín, and Moche.
Daniel H. Sandweiss, an anthropology professor at the University of Maine, said the discovery was significant—and also sheds light on a long-standing mystery. "The Lamabayeque valley complex is the largest extent of irrigable land on the Peruvian coast and offered many attractive resources for hunter-gatherer-fishers before irrigation agriculture.” However, preceramic occupations were virtually unknown there, even though most of the Peruvian coast has an abundant preceramic record.
The artifacts found in Ventarrón suggest that the region of Lambayeque was a cultural exchange point between Peru's Pacific coast and other regions. Alva’s team, as an example, found ceremonial offerings including the skeletons of a parrot and a monkey that would have come from Peru's jungle regions. They also found shells that would have come from coastal Ecuador, he said.
Michael E. Moseley, an anthropologist at the University of Florida, was not involved in the research, but added, "Dr. Alva has a track record for unique discoveries, and his latest unearthing of ancient temple murals greatly enlightens understanding of the vibrance of ceremonialism in native America millennia ago."
Luis Jaime Castillo, an archaeologist at Peru's Catholic University in Lima, agreed the finding is important. "It suggests that societies in their formative period, the period before complex societies came into being, extended into the northern reaches of Peru earlier than we thought."
Kelly Hearn of National Geographic Magazine explained that the finding was also fortuitous given the site's recent history. Over the years, Ventarrón has been almost totally destroyed by locals digging for materials to make adobe buildings and livestock corrals. The tomb at Ventarrón was ransacked in 1990 and 1992, but the raiders failed to find the staircase leading to the temple.
Archeologists on site have engaged many of Ventarrón’s community members in the temple’s excavation—empowering them as stewards of their cultural heritage. Following a similar ethic, the design and planning processes will rely heavily upon local knowledge and community contribution, and building projects will be constructed by community members, from locally sourced materials. Current plans include a museum, a community center, a clinic, schools, a central plaza, demonstration gardens, water supply and sanitation infrastructure.
Also found at the site to the side of the temple is a series of rooms that are shaped like the ancient Andean 12-point symbol called the Chacana—also known as the Andean Cross (Spanish: the Cruz Andina).
The Chicana design, symbolizing the Tree of Life, this stepped cross is made up of an equal-armed cross indicating the cardinal points of the compass, representing the Hana Pacha (upper world of superior gods), Kay Pacha (world of everyday existence) and Ucu or Urin Pacha (underworld or spirits of dead ancestors)
The three worlds of the ancient Andean Chicana are described in animals as Underworld (snake), Current World (Puma) and Upper World (Condor). Garcisalo de la Vega, known as El Ynga (The Inca), the half Inca prince and half Spanish historian wrote of this cross found in Cuzco after the Conquest and was a pre-Inca symbol bearing cultural and spiritual interpretations, and was originally found in pre-Columbian artifacts as textiles and ceramics, and two carved monoliths surviving in Ollantaytambo, and sixteen pointed crosses were found in Tiwanaku.
While no one really knows the actual meaning of these so-called crosses, what they stood for or why they were used, the point is that they permeate throughout ancient Peruvian cultures in textile, ceramic, and even building designs. They exist and had some meaning or purpose. Again, the point is that once again an iconographic symbol shows an obvious continuation of a theme through separate so-called cultures and time periods, suggesting that there is more reason to tie these varying cultures together into one overall civilization, such as the Nephites, than into separate, uninvolved and non-connected cultures as archaeology does.
As the Peruvian author Tupaq Katari once wrote: “When I hear you foreigners, with ease and lightness talking of the Andean themes, this surprises me, since we here in Peru continually try to find details about our own history, which is very complex and you argue so lightness without a historical or experiential support of what are the Andes and its diversity.”
Might not the Book of Mormon have more to do with the actual history of Peru than all the varying, conflicting and “lightness” of modern historians, scholars, archaeologists and anthropologists?
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Reproduced with permission of The Academic Wino
There are many factors that play a role on the quality and stability of wine. Specifically, both enzymatic and non-enzymatic oxidative reactions can significantly influence the aromatic and structural quality of a wine, which without appropriate control, can run rampant and cause off-aromas and flavors in the wine, thus spoiling the beverage. Spoilage microorganisms (such as certain yeasts and bacteria), as well as compounds naturally present in wine can cause oxidation reactions or become oxidized themselves, resulting in undesirable sensory characteristics in the finished wine.
In order to control these spoilage microorganisms and undesirable chemical reactions, winemakers employ SO2 (sulfur dioxide) during the winemaking process. Recently there has been a strong push for winemakers to reduce their usage of SO2, mainly due to the fact that SO2 exposure could be a health risk for certain individuals. Currently, there isn’t one compound or product that can completely replace SO2 in winemaking, though research is ongoing and has already found that reducing the amount of SO2 used in conjunction with another alternative technology could protect the finished wine just as well as higher levels of SO2 used alone. These alternative technologies include hydrostatic pressure, pulsed electric fields, ultrasound irradiation, and UV (ultraviolet) irradiation.
The study presented here proposes to examine the use of UV irradiation as a protective agent against wine spoilage, while comparing with SO2 and no treatment controls. The measure for determining if any of the treatments protected against wine spoilage or oxidation was polyphenol oxidase activity. Polyphenol oxidase is partially responsible for the browning of white wines after oxidation, so theoretically, if polyphenol oxidase levels are decreased, the wine is not oxidized (or is less oxidized) than a wine with higher polyphenol oxidase levels.
Two white grapes were used in this study: Xarel-lo and Parellada (from vineyards in Spain). Grapes were processed in a home juicer and then pressed. To remove any solids, juice samples were centrifuged then the liquid removed. The juice was then split, with half remaining as fresh juice and the other half going into a freezer. For both fresh and frozen juice, samples were split into the following treatments: 1) SO2 addition (50 mg/L potassium metabisulphite) prior to winemaking; 2) UV irradiation treatment prior to winemaking; and 3) winemaking without SO2 or UV treatments (control).
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542-488.3 mya
Life and Organisms
There were no land animals and no land plants. But there were animals with dorsal nerve cords and hard bodied brachiopods in water, like clams and arthropods, spiders, insects, and crustaceans. The predator animal was the Anomalocaris and Opabinia. There were also Sponges and Pikaia.
There was no significant ice formation. None of the continents were located at poles so the temperature was mild. Global Climate was probably warmer than it is today. Land masses were scattered from the fragmentation of Pangea. Pangea was broken up into four pieces of land which they called Laurentia, Baltica, and Siberia. There where Mountains, Oceans, Shallow Seas around the Continental Shelves. The ocean was called Iapetus Ocean.
Big image
Stratigraphic Series
The Cambrian Period was divided into 4 Stratigraphic Series. The first one was the Terreneuvian Series which was from 541-521 mya. The second was Series 2 which was from 521-509 mya. The third one was Series 3 which was from 509-497 mya. And the last one was Furongian Series which was from 497-485.4 mya.
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Pairs occupy a territory but usually roost and feed apart: their social behavior is sufficient to allow regular mating during the season and little else.
In winter, the male selects an area of ground, usually a small open space between the stunted trees of the mallee, and scrapes a depression about 3 m (9.8 ft) across and just under 1 m (3.3 ft) deep in the sandy soil by raking backwards with his feet. In late winter and early spring, he begins to collect organic material to fill it with, scraping sticks, leaves and bark into wind-rows for up to 50 m (160 ft) around the hole, and building it into a nest-mound, which usually rises to about 0.6 m (2.0 ft) above ground level. The amount of litter in the mound varies, it may be almost entirely organic material, mostly sand, or anywhere in between.
The female lays a clutch of anywhere from two or three to over 30 large, thin-shelled eggs, mostly about 15; usually about a week apart. Each egg weighs about 10% of the female's body weight, and over a season it is common for her to lay 250% of her own weight. Clutch size varies greatly between birds and with rainfall. Incubation time depends on temperature and can be anywhere between about 50 and almost 100 days.
Hatchlings use their strong feet to break out of the egg, then lie on their backs and scratch their way to the surface, struggling hard for five or ten minutes to gain 3 to 15 cm (1 to 5 in) at a time, and then resting for an hour or so before starting again. Reaching the surface takes between 2 and 15 hours. Chicks pop out of the nesting material with little or no warning, with eyes and beaks tightly closed, then immediately take a deep breath and open their eyes, before freezing motionless for as long as 20 minutes.
Chicks have no contact with adults or other chicks: they tend to hatch one at a time and birds of any age ignore one another except for mating or territorial disputes.
It occupies semi-arid mallee scrub on the fringes of the relatively fertile areas of southern Australia, where it is now reduced to three separate populations: the Murray-Murrumbidgee basin, west of Spencer Gulf along the fringes of the Simpson Desert, and the semi-arid fringe of Western Australia's fertile south-west corner.
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Explain why Stalin came to power by 1929
Extracts from this document...
Explain why Stalin came to power by 1929 (12 marks) There were many reasons why Joseph Stalin came to power by 1929, Stalin's personal skills and characteristics helped him but many outside factors such as the weaknesses of his opponents. One of the reasons Stalin was able to come to power was because of the control he gained of the communist centralised party machine, the position of General Secretary put him in a unique situation as he was able to influence job appointments by collecting information on each party member and then promoting those who were loyal to him and removing those who were disloyal to him. This allowed Stalin to gradually increase his power base and become more influential. Stalin was also able to get to power because of his personal characteristics and political skills. He was an "unscrupulous intriguer, who sacrifices everything else in the preservation of power..." ...read more.
by members of the party, especially the contenders, Stalin was described as "a grey blur which flickered obscurely but left no trace" by Sukhanov in 1917. "They were content to leave him (Stalin) to assemble and classify the personnel files, not yet realising what power was accumulating therein." No opponents saw in the Stalin of 1923 the menacing and towering figure he was to become. Stalin's opponents also had considerable weaknesses that allowed Stalin to succeed, especially Stalin's main opponent Trotsky. Even with his strengths such as his oratorical skills, intellect and charisma Trotsky had substantial weaknesses; he was arrogant and detached and lacked political skills. Historian Richard Pipes places great emphasis on Trotsky's personal flaws - his arrogant behaviour towards his colleagues, and his inflexible policy positions. These weaknesses created enemies for Trotsky and gave him no real power base to build on while Stalin was building a strong power base and slowly crafting his way to power. ...read more.
Stalin was able to expose this 'loophole' and was able to get opponents, especially his closest one Trotsky expelled. There was also a growth in party membership around the years of the power struggle, many of these members were young, inexperienced and poorly educated. Many of these party members were easy to dominate and influence and were more likely to obey instructions than some older party members, Stalin was able to gain support from these members and build a stronger power base. In conclusion, Stalin was able to come to power by 1929 due to many outside factors which he cleverly influenced and manipulated like the positions he took up in the Bolshevik Party, the ban on factions, the inexperience of some of the party members and most especially the weaknesses of his opponents either on the right or the left. But Stalin also used his individual skills and characteristics to gain support and work his way to the top. ...read more.
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* Some critics declare that Riefenstahl's films should be banned and not shown; others state that the films should not be celebrated as art, instead recognized for the role they played in their historical context. * The films have the ability and power to wield political influence beyond the 1930's.
2. Why was Stalin able to come to power by 1929?
The Lenin enrolment occurred between early 1923 to late 1925. During this time approximately 340,000 to 600,000 new members of the Communist party were created. The Majority of these members were highly uneducated; with only 8% of the ?Lenintsy? educated to secondary school standard.
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Canadian Geographic Education
geographic engagement
among Canadians
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Follow us on Twitter!
Human river
Grade level: K-4 (Approximately age range: 5-9 years old)
Objectives: Through this activity, students will understand that rivers can be polluted and that students' actions can make a difference in the water quality of rivers.
Relevant U.S. National Geography Standards: 14, 16, 18
Materials: River system diagram
Show students the river system diagram and discuss the different components. Ask them where they think they are located within a river system. Ask students to define litter. HAve them name items of litter. List the items on the blackboard. Ask, What eventually happens to litter? Help students define 'pollutants' and name different pollutants. Wher ehave students seen litter? Could litter or pollutants pose a problem for rivers?
Now, turn you class into a 'human river.' Have each studen select one article (paper, book, pencil, etc.) to represent a pollutant. Arrange students in a river pattern. 'Tributary' students lead into a line of 'river' students, with an 'ocean' student at the end of the line. Beginning with students at the 'source,' have students pass their article to the next student, and so on, until the 'ocean' student holds everything. Students could say things such as, 'I'm a dairy farmer, and my drtilizer pollutes the river,' or 'I'm a power plant, and I'm heating the river water.' How did the students toward the middle and end feel?
Remind students that pollution comes in different forms and from different places, but it could all end up down a drain, where it threatens your river. Encourage students to get involved in keeping rivers clean.
Adobe PDF download Human river (Adobe PDF document)
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Coccinella septempunctata
Coccinella septempunctata
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Superfamily: Cucujoidea
Family: Coccinellidae
Latreille, 1807
etc. see list of Coccinellidae genera
Pupal stage
Pupal stage
Early larva stage
Early larva stage
Mid-larva stage
Mid-larva stage
Coccinellids mating
Coccinellids mating
Coccinellidae is a family of beetles, known variously as ladybirds ( Commonwealth English), ladybugs ( North American English) or lady beetles (preferred by scientists). The word "lady" in the name is thought to allude to the Blessed Virgin Mary in the Catholic faith. Coccinellids are found worldwide, with over 4,500 species described, more than 450 native to North America alone. Coccinellids are small insects, ranging from 1 mm to 10 mm (0.04 to 0.4 inches), and are usually yellow, orange, or red with small black spots on their carapace, with black legs, head and feelers. As the family name suggests, they are usually quite round in shape. Because they are useful, colourful, and harmless to humans, coccinellids are typically considered cute even by people who hate most insects. Some people consider seeing them or having them land on one's body to be a sign of good luck to come, and that killing them presages bad luck.
Most Coccinellids mate in the spring or summer, and the female lays a cluster of eggs (numbering from a few to a few hundred, depending on species) as near as possible to an aphid colony. In most species these eggs hatch into a larval state within a week. This state lasts 10-15 days, and they then go into a pupal stage before becoming an adult coccinellid. The entire life cycle of the Coccinellid is only 4-7 weeks.
Commercial use
Coccinellids are beneficial to organic gardeners because most species are insectivores, consuming aphids, fruit flies, thrips, and other tiny plant-sucking insects that damage crops. In fact, their name is derived from "Beetle of Our Lady", recognising their role in saving crops from destruction. Today, they are commercially available from a variety of suppliers.
In agriculture, coccinellids, like other beetles, can find protection in beetle banks.
Coccinellids are and have for very many years been favourite insects of children. The insects had many regional names (now mostly disused) such as the lady-cow, may-bug, golden-knop, golden-bugs ( Suffolk); and variations on Bishop-Barnaby (Barney, Burney) Barnabee, Burnabee, and the Bishop-that-burneth.
The ladybird is immortalised in the still-popular children's nursery rhyme Ladybird, Ladybird:
Ladybird, ladybird, fly away home
Your house is on fire and your children are gone
All except one, and that's Little Anne
For she has crept under the warming pan.
Many variants exist, including one that seems ancient (recounted in an 1851 publication):
Dowdy-cow, dowdy-cow, ride away heame,
Thy house is burnt, and thy barns are tean,
And if thou means to save thy barns
Take thy wings and flee away!
The name which the insect bears in the various languages of Europe is clearly mythic. In this, as in other cases, the Virgin Mary has supplanted Freyja, the fertility goddess of Norse mythology; so that Freyjuhaena and Frouehenge have been changed into Marienvoglein, which corresponds with Our Lady's Bird. There can, therefore, be little doubt that the esteem with which the lady-bird, or Our Lady's cow, is still regarded and is a relic of ancient beliefs. In parts of Northern Europe, tradition says you get a wish granted if a ladybird lands on you. In Italy, it is said by some that if a Ladybird flies into your bedroom, it is considered good luck. In central Europe, a ladybird crawling across a girl's hand is thought to mean she will get married within the year. In Russia a ladybird is called Божья-Коровка (God's cow) and a popular children's rhyme exists with a call to fly to the sky and bring back bread. Similarly, in Denmark a ladybird, called a mariehøne (Mary's hen), is asked by children to fly to 'our lord in heaven and ask for fairer weather in the morning'.
The ladybird is the symbol of the Dutch Foundation Against Senseless Violence, as you can see in the logo here. Other companies using ladybirds as their corporate logo include: Ladybird Books (owned by Pearson PLC); the Ladybird range of children's clothing sold by Woolworth's in the UK; and Axosoft, a US-based software development firm whose flagship product helps manage the software development process, including defect (bug) tracking.
In the popular Pixar animated film, A Bug's Life, Francis the Ladybug is an aggressive male flea circus performer who is deeply annoyed when his gender is confused.
Two ladybirds are featured in the Peugeot 207 TV commercial. They are shown mating inside a Peugeot 207 to the tune of The Marcels' Heartaches.
Notable species
Note that not all individuals show the number of spots suggested by their names:
Asian lady beetle, Harmonia axyridis
Asian lady beetle, Harmonia axyridis
• Seven-spotted lady beetle, Coccinella septempunctata
• Two-spotted lady beetle, Adalia bipunctata
• Convergent lady beetle, Hippodamia convergens
• Thirteen-spotted lady beetle, Hippodamia tredecimpunctata
• Spotted lady beetle, Coleomegilla maculata
• Twice-stabbed lady beetle, Chilocurus stigma
• Mexican bean beetle, Epilachna varivestis Mulsant
• Asian lady beetle or Harlequin lady beetle, Harmonia axyridis
• Mealybug ladybird, Cryptolaemus montrouzieri
For a complete list of genera, see list of Coccinellidae genera. See also the list of British ladybirds
Long-range weather forecast
In long-range weather forecast, one species of ladybirds was studied over a period of ten years. In mild winters, they would hibernate in relatively shallow nestings. In cold winters, they would hibernate in deeper nestings. How they are able to predict the season's severity is still a mystery, but they were never wrong in ten years' time.
Additional Photographs
Retrieved from ""
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About Lymphoedema
What is lymphoedema?
In a normal person, fluid is lost from the circulation as it passes through the capillaries of a limb. This fluid is recycled back to the venous part of the circulation by a system called the lymphatics. Lymphoedema describes a condition where an excess of fluid builds up in the limbs, usually because of impairment to the outflow of lymphatic fluid from an affected area. Lymphoedema affects different people in different ways, and can cause excessive swelling, restricted movement, pain, recurrent episodes of severe infection (cellulitis), and subsequently a greatly decreased quality of life for the patient. It is very common, with over 100,000 people affected in the UK. By far the most common cause in the UK is the treatment of lymph nodes affected by cancer, by either surgery or radiotherapy. Up to 60% of patients treated for breast cancer and 60% of patients treated for gynaecological cancer are estimated to suffer with lymphoedema.
What causes lymphoedema?
Lymphoedema may be classified as primary or secondary, based on underlying cause. Primary lymphedema is caused by abnormal development of the lymphatic system. It can be present at birth, or develop later in life. Most commonly in the UK, lymphoedema develops secondary to damage to normal lymphatics. The most common causes of lymphedema are lymphatic damage from surgery (axillary or groin lymph node dissection), or radiotherapy. Worldwide, filariasis is the most common cause with damage to the lymphatics. Filariasis is caused by invasion of the lymphatics by a parasite called Wuchereria bancrofti.
What treatments are available for lymphoedema?
Conventional treatment for lymphoedema consists of meticulous skin care, self-massage, and specialist compression bandaging. This is performed by lymphoedema specialist nurses and therapists. At best, this can control the disease, but it fails to address the cause - an obstruction to the outflow of lymph fluid from the affected region. Furthermore, lymphoedema of some areas, for example the head or the scrotum, is not amenable to compression therapy.
What is supermicrosurgery?
Microsurgery describes surgery performed beyond the limits of human sight utilising the operating microscope. Supermicrosurgery takes this concept further, joining together vessels of between 0.2mm and 0.8mm in diameter, using sutures that are thinner than a human hair. This surgery requires high magnification, specialised equipment, and specialist technical expertise and training.
How is supermicrosurgery used in the treatment of lymphoedema?
At the Oxford Lymphoedema Practice, we use the most advanced minimally invasive supermicrosurgical techniques to relieve lymphoedema. Through tiny incisions, often less than 2cm (1 inch) in length, we find lymphatic channels and small veins just beneath the skin. We then connect the lymphatic channels to the veins. This gives the lymphatic fluid an alternative route to escape from the affected area, effectively bypassing the area of damage to the lymphatics.
Does supermicrosurgery work in the treatment of lymphoedema?
Yes. Supermicrosurgery is an effective treatment for established lymphoedema, and also it is effective at preventing lymphoedema in those at high risk of developing it. In the treatment of longstanding advanced lymphoedema, studies have shown that over 80% of people show improvements in their lymphoedema. In ladies undergoing removal of the lymph nodes in their armpit (axillary dissection) for treatment of breast cancer, just 4% of those undergoing supermicrosurgery subsequently developed lymphoedema. Supermicrosurgery has also been shown to be effective in treating lymphoedema in areas that are hard to treat by conventional compression bandaging, such as the scrotum. We have also found that supermicrosurgery vastly reduces the occurrence of infection (cellulitis) in the affected area. Some patients suffer leaking of lymphatic fluid through the skin (lymphorrhoea), and again, supermicrosurgery is extremely effective at treating this distressing problem. Unlike previous surgical treatments that were disfiguring, and fraught with risk and complications, modern supermicrosurgical techniques – though technically demanding – are minimally invasive, and have been shown in numerous studies published in peer reviewed medical journals to be highly effective. Furthermore, supermicrosurgery for lymphoedema has a very low complication rate, with possible complications including infection, lymph leak, and rarely worsening of lymphoedema (though as lymphoedema is a progressive disease this may be failure to interrupt the cycle of worsening lymphatic function).
Lymphoedema in leg
Left leg lymphoedema
Lymphoedema in arm
Left arm lymphoedema
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by Peyton Stauffer
Best Mariachi Music
History and General Information
Mariachi is a popular form of music formed in Mexico over one hundred years ago. It was known as "the music of the people." Majority of people living in Mexico were fond or familiar with this genre of music. This music was used in celebration, triumphs, and during struggles. Mariachi music was used to celebrate birthdays and saint's days.
Characteristics of the Music
What is it? - a type of traditional Mexican folk music, typically performed by a small group of strolling musicians dressed in native costume
Main instruments - violins, trumpets, guitars, vocals
Associated Events - birthdays, holidays/saint's days, everyday occasions
Costumes - traditional Mexican costume
Famous Artists - Luis Miguel, Vicente Fernández, Pepe Aguilar, Juan Gabriel
Connections to Dance
Associated Dances - Mexican Hat Dance:
Mariachi is said to be incomplete without the Mexican Hat Dance. The Mexican Hat Dance, also known as Jarabe Tapatío, is a traditional Mexican dance that has been said to symbolize Mexico both domestically and internationally. This dance represents the courtship between a man and a woman and is performed by a man and a women.
Mexican Hat Dance (Full Version)
Mariachi Today
Mariachi is still a popular form of music today. The instruments slightly vary from those of traditional mariachi music including newer variations of the instruments. Mariachi is considered traditional Mexican music.
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next curve previous curve 2D curves 3D curves surfaces fractals polyhedra
Curve studied by Barrow (one of Newton's professors) in 1669, by Quételet in 1810 and by Chasles; the name was given by Montucci in 1846.
Strophoid comes from the Greek strophos "string, belt, braid".
Other name: Quételet focal, nodal focal, harmonic curve.
The tangent at the focus F recuts the curve at the intersection point S with the asymptote.
Polar equation:
= 0: right strophoid = p/2: limit case of the circle.
Focus ; asymptote : x = a cos
Intersection point with the asymptote: S.
Inflection point obtained for .
Cartesian equation: .
Rational circular cubic with a double point.
In the frame (F):
Cartesian equation: .
Complex equation: , with .
Polar equation:
i.e., the case + giving the same curve as the case -.
If and are swapped, then the polar equation simplifies to: (so a conchoid of a right strophoid).
Given two points O and F and a line (D0) passing by O, the strophoid with focus F, double point O and axis (D0) is the locus of the points M on a variable line (D) passing by F such that PM = PO, where P is the intersection point of the lines (D) and (D0) (in other words, it is the strophoid of (D0) with respect to O and F).
The strophoid is the locus of the points M such that PM = PO
The strophoid is therefore also the locus of the contact points of the tangents passing by F to the circles tangent at O to the axis (D0).
It follows from this definition that the axis (D0) of the strophoid is the median with pole O of the strophoid with itself.
Here, O is the origin of the frame, F is the point , and (D0) is the axis Oy; the asymptote is the line parallel to (D0) passing by the symmetric image of F about (D0).
Animation showing the construction of the right strophoid by the Newton set-square method, and of two conchoidal strophoids.
See details on the page dedicated to the glissettes.
The complex equation shows that the strophoids are the loci of the point M such that, if its image by the composition of an inversion with centre F and a reflection about (OF) is called M', then the middle of MM' describes a line (D0) passing by O; M' is called the conjugate of M.
The middle I of [M M'] describes the line (D0); M1 is the inverse with pole F of M with respect to the circle (C) and M' is the symmetric image of M1 about (Da ).
If A and A' are two conjugate points of the strophoid, M any point on this curve, then the line (OM) is a bisector of (AMA'); inversely, given 3 unaligned points O, A, A', the locus of the points M such that (OM) is a bisector of (AMA') is a strophoid, and so is the locus of the points M "seeing" the oriented segment lines [AO] and [OA'] under the same angle.
The strophoid is therefore a special case of the isoptic cubic, locus of the points from where two segment lines can be seen under the same angle.
A non-flat triangle (ABC) thus gives 3 strophoids:
(SA) defined by (MC, MA) = (MA, MB) in mauve
(SB) defined by (MA, MB) = (MB, MC) in brown
(SC) defined by (MB, MC) = (MC, MA) in green
When the triangle is flat, these loci are circles of Apollonius, hence the name strophoids of Apollonius given to these curves.
The three curves have, in general, 5 common points: the 3 vertices, the Fermat point of the triangle F1 , defined by if (ABC) is direct, and the second Fermat point F2 defined by . F1 and F2 are the two isogonal conjugates of the triangle.
All the curves also pass by the foot of the altitude passing through the indexed point.
See this website.
The strophoid is also found in the following optics problem: an observer B looks at the image A' of a fixed point A in a mirror turning around a fixed point O; the locus of the intersection points of the ray BA' with the mirror is a strophoid with double point O, focus A, and axis parallel to (BE) constructed on the figure. If D is the symmetric image of A about OB, then the line (BD) is the tangent at B.
The strophoids have another elegant 3D construction discovered by Quételet, as the locus of the foci of conics (hence the name: Quételet focal): if S is the intersection point between the strophoid and its asymptote, and (C) is the cone of revolution with axis (OS) passing by F (and half-angle at the vertex ), then the strophoid is the locus of the foci of the conical sections of the cone (C) by the planes perpendicular to the plane (OSF) passing by F.
S, vertex of the cone, M and M': foci of the conic on a plane perpendicular to (OSF) passing by F; the centre I of the conic describes the axis of the strophoid.
For the right strophoid, the cone becomes a cylinder.
Like all the rational circular cubics, the strophoids can be defined as:
- the cissoids with pole O of a circle passing by O and a line passing by the symmetric image of the centre of the circle about O (here, the circle is the circle (C) with centre F passing by O, the line, the line parallel to (D0) passing by the symmetric image of F about O).
- the pedals of a parabola with respect to a point on its directrix (here of the parabola with focus the symmetric image of O with respect to F and directrix the axis (D0) of the strophoid).
The focus of the strophoid is at the middle of the segment line joining its double point to the focus of the parabola.
The strophoid is therefore also the envelope of the circles with diameter joining O to a point on the parabola; in other words, it is the cyclic with initial curve, or deferent, a parabola, when the radius of inversion is zero and the pole is on the directrix of the parabola.
- the inverses of a rectangular hyperbola with respect to one of its points (here O)
The point F is a singular focus of the curve: the strophoids are therefore special cases of focal circular cubics (hence the name: nodal focal, in other words, focal with a double point).
See cochleoid and Mobius surface.
next curve previous curve 2D curves 3D curves surfaces fractals polyhedra
© Robert FERRÉOL 2017
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Invent a Backscratcher from Everyday Materials
Type of Resource
Being able to recognize a problem and design a potential solution is the first step in the development of new and useful products. In this activity, students create devices to get "that pesky itch in the center of your back." Once the idea is thought through, students produce design schematics (sketches). They are given a variety of everyday materials and recyclables, from which they prototype their back-scratching devices.
Performance Expectations
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Binary Operation MCQs Quiz Online PDF Download
Learn binary operation MCQs, math test for learning online courses and test prep to practice. Number system quiz has multiple choice questions (MCQ), binary operation quiz questions and answers, linear and quadratic function, rational numbers and irrational numbers, groups in maths, operation on three sets, binary operation tutorials for online best math courses distance learning.
College math practice test MCQ: * is said to be commutative in a for all a,b ε a with choices a + b = b + a, a * b = b * a, a - b = b - a and a * b ≠ b * a for online preparation of college courses for qualifying in jobs for college students. Free study guide is for online learning binary operation quiz with MCQs to practice test questions with answers.
MCQs on Binary Operation Quiz PDF Download
MCQ. * is said to be commutative in A for all a,b ε A
1. a + b = b + a
2. a * b = b * a
3. a - b = b - a
4. a * b ≠ b * a
MCQ. Extraction of a square root of a given number is
1. binary operation
2. relation
3. unary operation
4. relation in some set
MCQ. Which of following is unary operation?
1. addition
2. multiplication
3. square root
4. None of Above
MCQ. Identity element of a set X with respect to intersection in P(X) is
1. X
2. π
3. does not exist
4. 0
MCQ. If * is a binary operation in A then
1. A is closed under *
2. A is not closed under *
3. A is not closed under +
4. A is closed under -
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Goddess Worship
In the beginning, the goddess was known, loved, and revered by humankind. The goddess, as the Creatress, was given primary reverence. Archaeology has turned up many clues that point to the earliest. Cultures being matriarchies; this does not mean female-controlled but rather ruling partnerships. Between men and women. Because the women were responsible for bearing and raising the all-important children, they tended to live in fixed groups, agricultural communities that provided as stable base for the hunting of males. Women domesticated animals, learned the intricacies of growing plants, and establish small religious centers. They developed medicine, divinated, writing, pottery,weaving, and other types of art and domesticated crafts.
The female elders passed the laws that
regulated the communities, keeping the people in peaceful harmony among themselves and with outsiders. Archaeology’s present methods at dating antiquities are still being refined; knowledge is limited. As new methods of dating are discovered, the time of humankind on this planet is pushed further and further into the past. At present calculations, matriarchies and worship of the goddess extend back 40,000 to 50,000 b.c.e. During paleolithic times, sacred objects and the dead were painted with red ocher, a symbol of menstrual blood for recreation. Religions sites such as caves and temples contain the remnants of shells, particularly cowrie shells, which represent female sexual organs. Ancient cave paintings, bas reliefs, and statues were overwhelmingly of the goddess; male depictions during these times were only in peripheral positions, as were their symbols.
Some what later in history
the goddess began to be pictured with animals, trees, and symbols of water. Sometimes she was portrayed as being part animal. This is symbolic linkage of her direct connection with all nature. The religious beliefs, the mysteries and rites developed by ancient women, grew organically out of women’s supreme roles as cultural producers, mothers and prime communicators with the spirit world. The Mysteries of creation, transformation, and recurrence- the primal mysteries of All religious- emerged from women’s direct physical and psychic experiences of the mysteries: in bleeding, in growing a child, in nursing, in working with fire, in making a pot, in planting a seed. In pottery-craft and myth alone,we can see the development of a religion. The pot was seen to have the body shape and internal womb of the mother.
In neolithic Europe, clay was said to have"a woman's soul”, and no man was allowed
to see the female potter at work. Clay, sacred to women and the goddess, was often marked with theMaze-like windings of the magic underworld, a place for transformation. Aruru –Ishtar, the Cosmic Creatrix of Babylon, was imaged as a potter. A divine potter, shaper of life. The making of cult vessels was like the shaping of life, and the Babylonians words for rebirth were (we are as fresh-baked pots). From this, we can see the absurdity (and political cooperation) of the notion of a male-god-father making human beings from clay or dust. The biblical image is stolen without shame from the earlier Sumerian and Babylonian goddess creation stories. Such a patriarchal version of creation is very recent; the facts of women’s experience of life are primordial. It is the woman who goes through the sacred transformation in her body and psyche- the mystery and changes of menstruation, pregnancy, birth, and the production of milk.
It is woman who first shaped a seed into food, earth into pottery, fire
into a tool, the struggle for survival into human cultures. During the millennium before Jesus, continuing into the first five hundred yrs. Thereafter, the major divinity of the Mediterranean world appears to have been Auset of Africa,( called Isis by the Greeks), dark mother of many names, Great Mother of the Mediterranean. Isis inherited a long matriarch tradition of Africa who signs were the color red ochre and the pubic v, as well as spirals and circles and human identification with animals.
Scholarship since
the 1960’s has recovered what the ancients knew: Isis was an African deity, whose origins were in Nubia, or upper Egypt. The study of Nubian archeology and history has established the centrality of the dark mother Isis, who is considered to have exemplified African matriarchal traditions. It was only through the royal women that the Nubian ruler inherited the throne. All kings and queens had to be born to a queen. Usually the ruler’s sister. The seamless fit between religion and daily life in Africa is suggested by the fact that an African woman, as priestess of the dark mother, was “mistress of heaven” as well as “mistress of the house”. The image of Isis most popular at the height of the roman empire appears to have been that of Isis nursing her child, Heru (called Horus by the Greeks, Apollo by the Romans, and Jesus by the Europeans.).
Besides queen of sea, Isis was considered queen of heaven and of earth, and
was easily transmuted into the christian holy mother. Legions of the roman empire, whose ranks were drawn from subordinated dark peoples of three continents, carried images of African Isis, as images of Isis melded together with west Asian divinities Cybele, Inanna, and Astarte all over the known world, from Africa to Asia, to Rome, France, England, to the Danube. At Benevento, where the great Isis flourished in the roman epoch, her followers were later called witches. If you’ve gotten this far I bet you’re asking why haven’t I heard of this before? And if the worship of the goddess is real what happen? Why are we not embracing the goddess now? I’ll go briefly into what happen in part.
If life is inherently evil, the church fathers needed someone to blame; and who better to blame than the
Woman, who created life from her own body? Living women, also, can be publicly punished, as the iconic and illusory devil can never be. The myth of feminine evil which has dominated the westernized world for over two thousand yrs. led logically and directed to the religiously targeted murder of women as witches during the Great Inquistition of Europe. The number of deaths from the inquisition was euphemistically underestimated as a way of denying about five hundred yrs. of systematic persecution and slaughter by the holy christian church. The deaths range from 1 million to 9 million people burned as witches between the fifteen and eighteenth centuries (between 1200 and 1500 people were officially killed as heretics). In 1484, pope innocent the eight pronounced a papal bull against the now suddenly discovered crime of witchcraft. He denounced witchcraft as an organized conspiracy of the devil’s army against the peace and common order of the holy christian empire( a peace and common order which people living under the empire had rarely experienced.)
And thus the war against women
was officially launched by the christian papacy, as a diversionary tactic to keep itself in power through the strategy of sheer terror. In the late middle ages, dominated by the christian inquisition, the delivery of a pregnant woman was no longer considered a sacrament but a dirty business, and the woman who attended the poor at child birth were frequently considered social outcast or worse. They were charged with again witchcraft, tortured, and burned. One witch was burned alive in Scotland for the sole crime of bathing some neighborhood children, for hygienic reasons, in the midst of epidemic. Health care and healing were publicly discouraged by the christian church, which officially believed that life was supposed to be diseased, wretched, and painful- this is god’s will, as punishment for human sin.
People who tried to alleviate suffering or cure illness, especially through ancient folk and herbal medicines, or simple hygiene were suspected to be agents of the devil. During the time of catholic-dominated Europe, it was also a crime against god to miscarry. Even if a woman miscarried after being beaten by her husband, she could still be put to death for her “sin” against the father because all miscarriages were suspected by the clergy of being intentional abortions. The celibate clergy always tended to believe women were guilty until proven dead. Even the word Hell, comes from the Norse goddess Hel of the underworld. Though christian theology gave its underworld the name of the Goddess Hel it was quite a different place from her womb of regeneration. The ancients didn’t view the Underworld as a primarily a place of punishment. It was dark, mysterious, and awesome, but not the vast torture chamber Christians made of it.
The idea of eternal torture in hell arose with ascetic
Patriarchal religions like that of Zoroastrian Persia, Judaism, and Islam. Masculine preoccupation with pain stood in contrast to the matriarchies’ preoccupation with pleasure, a physic outgrowth of the severities of ascetic life. There is reason to believe hell’s nastier torments were INVENTED primarily to intimidate women into obeying new patriarchal laws. Zoroastrian priests insisted women who were unfaithful to their husbands would go the hell and have their breast torn open with iron combs. Women who scolded would be forced to lick hot stoves with their tongues. Women who showed disloyalty to men would be hung up by one leg, while scorpions, snakes, ants, and worms dug their way in and out of their bodies. A similar vision inspired Grunwald’s medieval picture of the hellish torments in store for those who committed the crime of loving. But not even the Persians supposed the torments of hell would go on forever. That refinement of cruelty was left to the Christians.
The Jews adopted the Persians hell as a place for punishing the majority of women, judge hopelessly unworthy of the Father-Gods heaven. Men could be consigned to hell for holding to much unnecessary conversation with their wives,or for taking feminine advice. While I'm at it, let me give you a little info on this thing we call Sin. Sin the original Moon-god of Mount Sinai, “Mountian of the Moon.” He was born of the Virgin Queen of Heaven, Nanna or Innanna. He ruled the land of SINIM (ISAIAH 49:12), which meant “land of lunar mountain” and was an older form of Zion. His Chaldean name was Kingu. He was the god who received the Tablets of Law from the primal Mother of Creation, Tiamat as Moses’s god, he still had the same mountain-throne and the same tablets. A biblical scholar has pointed out “the Jehovah of the Hebrews” was merely another transformation of “the primitive lunar deity of Arabia. The God Moses met on Mount Sinai claimed to be the god of Abraham, though he said Abraham knew him by a different name (Exodus 6:3). In fact, Abraham may have been the same deity. Very ancient documents used the name Abraham or ab-ram as a synonym for ab-sin, moon-father.
In the 12th century b.c the Babylonian heaven was ruled by a trinity consisting of Shamash, Sin, and Ishtar, represented by the sun, moon, stars. And this info is barely scratching the surface of the suppression of goddess worship by patriarchal societies or male dominated religions.
Information from Khepera of myspace
1. *feeling like i have tons of reading to do ;-) *
this is an information packed online spot you have here. thank you for sharing so much of what you know regarding the divine feminine.
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How Did Vanishing Islands Give Birth To Sea Monster Tales?
Islands that appear and disappear at different times due to the tidal effects have often inspired sea monster stories popularized by sailors.
Islands that appear and subsequently vanish because of the tidal effects are often associated with sea monster stories told by sailors. Vanishing islands are visible at low tide, but they disappear at high tide. The Philippines is home to seven of such islands while the San Juan Islands have several of them. In the medieval period, seamen created their explanations for the strange phenomenon. The explanations mainly revolved around large sea monsters which would accommodate a crew on its back before drowning it. Some of the sea monster tales associated with such disappearing islands have been described below:
The Tale Of The Merciless Aspidochelone
The tradition of the Physiologus, as well as, the medieval bestiaries mention the Aspidochelone as a fabled sea creature that is described in a variety of ways that range from a giant sea turtle and a huge whale to a sea monster sporting massive spines along the ridge of its back. Regardless of the form it assumes, the creature is described as enormous and it is sometimes mistaken for a rocky island complete with valleys, crevices, trees, dunes, and greenery. The term Aspidochelone combines the Greek word aspis meaning shield or asp and chelone meaning turtle. It was said to emerge to the surface from where it would attract sailors mistaking it for an island. After the sailors anchored, the creature would make a landfall on its large shell and would retreat to the depths of the ocean together with the ship and the people. Aspidochelone also lures fish populations with its sweet smell.
According to the bestiary and Physiologus traditions, Aspidochelone is portrayed as representing Satan who tricks those he aims to devour. This monster is called Fastitocalon in the Old English poem by the name "The Whale." The name Fastitocalon is probably a variant of Aspidochelone, and it represents the Devil. The poem's author remains unknown and it is among the three poems in the Physiologus or Bestiary included in the Exeter book. The Exeter book is accommodated in the Exeter Cathedral Library. The book, having undergone mutilation and translation, has some of its content missing or changed. In the account titled Natural History, Pliny the Elder describes an enormous fish which he calls Pristis.
The allegory of Aspidochelone is based on the description of whales in Etymologiae which was the work of Saint Isidore of Seville. Aspidochelone goes by different names in various cultures. It has been noted in traveler's myth and lore across Greece, the Latin World, Egypt, and Europe. A similar beast is included in the folklore of Greenland's Inuit societies as Imap Umassoursa. The beast was commonly mistaken for a flat island and sailors were forced to travel carefully around it. Another sea monster thought to be an island was Jasconius in Irish folklore. Another title used for Aspidochelone is Zaratan commonly used in the Middle East. Another massive sea monster is called Hide or Cuero in Chile. The monster is said to devour whatever it comes in its path, and it also lures sailors to their ultimate death.
Lyngbakr, The Monster In The Greenland Sea
A huge whale-like sea beast was presented in the Örvar-Odds saga as existing in the Greenland Sea. The saga described Lyngbakr as a heather-covered island which baited sailors only to sink into the sea together with the crew. The myth begins with a southwesterly journey of Örvar-Oddr and his crew across the Greenland Sea. As they sailed, they noticed two rocks jutting out of the water which puzzled Oddr. The crew later passed a heather-covered vast island. Oddr turned back and commissioned five men to check the island, but it had vanished. Vignir, the deck officer told Oddr that the crew would have drowned if they had landed sooner.
Hafgufa, The Monster That Ate Ships
The medieval Norwegian philosophical didactic publication by the name Konungs skuggsjá mentions the sea monster Hafgufa. In the written work, the King recounts to his son of the multiple whales existing in the Icelandic Seas. The King concluded by describing a massive whale that he was scared of but was uncertain if anybody else would believe him without sighting the monster. The King explained the Hafgufa as resembling an island than a living creature and added that it was rarely sighted and when it was sighted in same two locations. The King hypothesized that there were only two of them and that they must have been infertile else the seas would be inhabited by many of them. For feed purposes, the King explained that the creature would belch to expel food and thus attract fish. As soon as a large population had congregated in its mouth and belly, the creature would close its mouth. The Örvar-Odds saga notes Hafgufa as the mother of sea monsters whose food sources included men, whales, and ships. Hafgufa was believed to exist underwater only to emerge at night at low tide. The creature's nose and head would be the only physical parts that were visible.
The Legend Of The Kraken
As legend has it, a sea monster named Kraken exists off the coasts of Greenland and Norway. Over time, authors have postulated that the legend's origins lie in the sightings of giant squids capable of growing 40 to 50 feet. Kraken has been fictionalized in various works owing to its fearsome appearance and massive size. The English term Kraken originates from the Norwegian Krake meaning "something twisted" or an unhealthy animal. The term also means octopus in modern German. The author of Konungs skuggsjá (circa 1250) described the sea monsters sighted in a voyage across the Greenland Sea. The author suggested that there were only two of these beasts in existence which seemed incapable of reproducing.
The zoologist Carl Linnaeus accommodated Kraken as a cephalopod and gave it the scientific identity of Microcosmus marinus in the initial edition of his Systema Naturae in 1735. The creature was subsequently excluded in successive publications. Kraken was also noted in a publication by Erik Pontoppidan who was the bishop of Bergen. Pontoppidan claimed that Kraken was often mistaken as an island and that the whirlpool left in the creature's wake posed the greatest danger to sailors. The creature was also described by Jacob Wallenberg who was a Swedish author and Pierre Dénys de Montfort, a French malacologist. Kraken is commonly depicted as a massive Octopus-like creature, and its legend exists in today's popular culture.
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"url": "https://www.worldatlas.com/articles/how-did-vanishing-islands-give-birth-to-sea-monster-tales.html"
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Do You Feel Alone? An Anthropological Explanation To Your Feeling Of Loneliness
Your emotions developed during the paleolithic period. Before the neolithic revolution, which gave rise to farming villages, people used to live in communities of about 150 individuals. But they were not communities of unrelated individuals, they were all family. Pre-neolithic families were composed of 150 individuals, who collaborated with each other to insure the survival of the community. So, throughout his life, a pre-neolithic individual lived together with 150 other individuals. Throughout his life, an individual lived together with the same 150 individuals. Not only were they related, they all did something for each other. They all emotionally invested in each other by way of conversations and collaborative actions. Because each individual had a very significant emotional investment in the other members of the community, the consanguineal bonds were very strong.
For over 150,000 years, 150-member communities existed. But that began to change during the neolithic period, when 400-member farming villages appeared. The rise of farming villages modified the social structure of those early families. Several early families agglomerated in a single community but spread over a larger area. In addition, living quarters compartmentalised those early families. So, a member of the village didn't interact with the same individuals on a daily basis as was the case when he was a member of a pre-neolithic community. The frequency of interactions with the same individuals was reduced in order to increase the social interactions with the other members of the village. And, due to the new social structure, bartering took precedence over collaboration. Therefore, an individual's emotional investment in the other members of the community was significantly reduced.
Nowadays, related individuals are spread over enormous distances. So they don't see each other on a daily basis. They don't talk to each other on a daily basis. They don't even interact between each other by way of bartering. Due to the current social structure, they don't need to collaborate with each other in order to survive, although if they were to collaborate, consanguinial groups could increase their chances of survival. In the current social environment, the emotional investment between related individuals is almost nil.
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The Production Process of Older Chinese Coins
gold_8259244 1For a period of over 2,000 years, since the Han Dynasty (206 BC – 220 AD) until the early 20th Century, the standard form of coinage in China was the copper-based quan (or ‘cash’). This was a round copper alloy coin with a distinctive square hole in the centre, featuring an inscription, and cast from a sand-based mould. Such coins were used almost exclusively as the official currency for everyday use in China over this period.
While the exact metallurgic composition of these coins changed over the two millennia that they were in use, the production process remained largely unchanged. Coins were cast, rather than struck – which was the common practice for western coin production at the time. They were cast in two-piece moulds. Moulds were made by softly pressing a master coin into a wooden box filled with sand. The sand was bound with some sort of organic matter so that it would hold the shape pressed into it. A second box was then laid on top and pressed together. The boxes were then pulled apart and the master coin removed. A two-piece mould was thus made, one box containing an imprint of the obverse face, the other the reverse face.
Channels were then made in the sand between the impressions along with a channel in the centre of the mould to allow for the molten metal to run in. The boxes were then fired to harden the sand and organic matter mixture. Now the moulds were ready for use and the metal was poured in, resulting in a t-shaped coin tree. The coins were then separated from the tree and then filed to smarten them up, removing any remnants of the tree.
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Article | Open | Published:
Scientific Reports volume 2, Article number: 355 (2012) | Download Citation
The genetic origins of modern Japanese have been debated and three models are noteworthy1. In the ‘continuity’ model, modern Japanese are considered as direct decedents of Jomon, the inhabitants of Japan in Paleolithic time, while their morphology showed secular changes2. In the ‘admixture’ model, Jomon admixed with the Yayoi, more recent continental immigrants, which is consistent with the rapid changes in morphology and culture which took place synchronically about 2,500 years before present (BP)1,3. In the ‘replacement’ model, Paleolithic Jomon was completely replaced by the continental immigrants (Yayoi) after their arrival4. To date, the ‘admixture’ model is seemingly better supported by the increasing lines of evidence of multiple genetic components found in modern Japanese5,6,7.
The upper Paleolithic populations, i.e. Jomon, reached Japan 30,000 years ago from somewhere in Asia when the present Japanese Islands were connected to the continent8. The separation of Japanese archipelago from the continent led to a long period (13,000 – 2,300 years B.P) of isolation and independent evolution of Jomon9. The patterns of intraregional craniofacial diversity in Japan suggest little effect on the genetic structure of the Jomon from long-term gene flow stemming from an outside source during the isolation10. The isolation was ended by large-scale influxes of immigrants, known as Yayoi, carrying rice farming technology and metal tools via the Korean Peninsula. The immigration began around 2,300 years B.P. and continued for the subsequent 1,000 years5. Based on linguistic studies, it is suggested that the immigrants were likely from Northern China, but not a branch of proto-Korean11.
Genetic studies on Y-chromosome and mitochondrial haplogroups disclosed more details about origins of modern Japanese. In Japanese, about 51.8% of paternal lineages belong to haplogroup O6, and mostly the subgroups O3 and O2b, both of which were frequently observed in mainland populations of East Asia, such as Han Chinese and Korean. Another Y haplogroup, D2, making up 35% of the Japanese male lineages, could only be found in Japan6,12. The haplogroups D1, D3, and D*, the closest relatives of D2, are scattered around very specific regions of Asia, such as the Andaman Islands, Indonesia, Southwest China, and Tibet13. In addition, C1 is the other haplogroup unique to Japan6,12. It was therefore speculated that haplogroups D2 and O may represent Jomon and Yayoi migrants, respectively6. However, no mitochondrial haplotypes, except M7a, that shows significant difference in distribution between modern Japanese and mainlanders5. Interestingly, a recent study of genome-wide SNPs showed that 7,003 Japanese individuals could be assigned to two differentiated clusters, Hondo and Ryukyu, further supporting the notion that modern Japanese may be descendent of the admixture of two different components7.
However, the estimation of contribution of the Paleolithic contingency, i.e. Jomon, to modern Japanese posed a technical challenge since all contemporary populations in Japan were subject to admixture at various levels and the ‘pure’ Jomon no longer exist. The STRUCTURE and similar analysis does provide a solution of estimating the relative contribution of different components in admixed populations when both parental populations are available14,15, but such approach was challenged for its accuracy especially when information on parental populations is incomplete16,17.
In this report, we estimated the relative contribution of Paleolithic inhabitants (Jomon) and more recent immigrants (Yayoi) to modern Japanese, under the assumption of the ‘admixture’ model. This was achieved with only one of the parental populations (Yayoi) was available while another parental population (Jomon) was missing. We also explored the possibility of inferring the genetic origin of Jomon.
Genetic contribution of Jomon in mordent Japanese
With the given two-population admixture model (Figure 1, see Materials and Methods section for details), the contributions of Jomon to Hondo Japanese (JP_ML) and Ryukyuans (JP_RK) were estimated by using genome-wide SNP data. Genotypes of both JP_ML and JP_RK populations were produced in PanAsia SNP project (see S1 of Supplementary file).
Figure 1: Demographic model of population admixture with missing population.
Figure 1
The original genetic donor to Yayoi migration is still controversial, both Korean and Chinese (northern or southern Han) were potential candidates5,18. Since genetic difference exists between northern and southern Han Chinese populations19, we examined the possible contribution of both northern Han Chinese (NH, combining data of CHB in HapMap project and NHan in HGDP) and southern Han Chinese (SH, combining data of CN-SH in PanAsia SNP project and SHan in HGDP) respectively in this study. We also examined the contribution of northern East Asian population by combining data of NH and Korean (NHK, including NH and Korean population named KR-KR in PanAsia SNP project) since previous genetic studies differed on whether Koreans were the only immigrants in period of later Jomon and early Yayoi5. Therefore totally three potential genetic sources (NH, SH and NHK) were evaluated respectively as continental genetic donor.
The estimated contribution of Jomon to modern Hondo Japanese ranges from 0.231 to 0.395 for different donors (Figure 2). The contribution of Jomon (0.231) is the lowest, when NHK (combination of Northern Han and Korean) was taken as the donor, with 95% confidential interval (C.I.) 0.215–0.266. When NH and SH were taken as donors, estimated contributions were 0.395 (C.I. 0.379–0.421) and 0.376 (C.I. 0.344–0.387), respectively. In contrast, Jomon's contribution in modern Ryukyuans is much greater than that in modern Hondo Japanese, regardless the choice of donors. The estimated contribution are 0.543 (95% C.I. 0.512–0.567), 0.605 (95% C.I. 0.605–0.648) and 0.623 (95% C.I. 0.623–0.671), for NHK, NH, and SH, respectively (Figure 2).
Figure 2: Estimated contributions of Jomon in different genetic scenarios.
Figure 2
Proportions of Jomon's contribution were marked on y-axis and names of the Asian mainland donors were presented on x-axis. Results based on parameters presented in table 1 were shown in blue columns. Open columns presented estimations from scenarios where Jomon's Ne is only a half of before. Black bars indicated 95% C.I of the estimations.
Combining lines of evidence from the above results and previous reports on both maternal and paternal lineages, none of the three possible donors can be excluded from the model for peopling of Japan. We therefore averaged the above estimations from all three possible donors to assess the proportion of Jomon contribution in modern Japanese. Thus, in Hondo Japanese, 33.4% of genetic component was derived from Jomon, whereas, 60.5% of its genetic component in Ryukyuans may come from Jomon. These estimations based on autosome data are consistent with previous studies using frequencies of Y haplogoups in modern Japanese populations. In particular, overall frequency of Japanese specific Y lineages, D2 and C1, is about 60% in Okinawa (Ryukyu) and 26.446.2% in Japanese mainland6.
It is likely that the effective population size (Ne) of Jomon was relatively smaller than that of the populations in Asian mainland, because history of agriculture is relatively shorter in Japan Archipelago than that in Asian mainland. We applied our estimation in scenarios that Ne of ancestry Japanese is only a half of the size in aforementioned estimations. The extent evaluation shows the reduced Ne led to only minor changes to the estimations of Jomon contribution (Figure 2). In particular, the estimated contribution with reduced Ne is 0.194 (95% C.I. 0.146–0.220), 0.326 (95% C.I. 0.321–0.356) and 0.369 (95% C.I. 0.356–0.387) for Hondo Japanese and 0.510 (95% C.I. 0.490–0.525), 0.557 (95% C.I. 0.546–0.592) and 0.575 (95% C.I. 0.554–0.602) for Ryukyuans with three possible donors, respectively. In other words, the estimations are robust to the changes of the parameters of demographic model.
Genetic affinity of Jomons
With the genetic contribution of Jomon in Ryukyuans and Hondo Japanese being 33.4% and 60.5% respectively, allele frequencies of SNPs of ancestral Jomon populations were inferred using the maximum likelihood (ML) method described in the Materials and Methods section. Overall allele frequencies in 6 virtual Jomon populations (JOMON ML-NH, JOMON ML-SH, JOMON ML-NHK, JOMON RK-NH, JOMON RK-SH and JOMON RK-NHK) were inferred based on two extant Japanese populations, i.e. Hondo and Ryukyuans, and three possible continental donors including NH, SH, and NHK. The inferred allele frequencies of Jomon populations allowed the reconstruction of the phylogeny including Jomon and the extant populations, using coancestry coefficient20 as the measurement of genetic distance and Neighbor-Joining method (NJ) for phylogeny reconstruction. Interestingly, all six inferred Jomon populations fell into the group of Northeast Asian populations but not that of the populations in South Asia or Southeast Asia (Figure 3A). The results of Principle Component Analysis (PCA) confirmed the genetic affinity shown in the NJ tree (Figure 3B). Jomon is therefore genetically closer to North Asian populations than it is to any other populations, suggesting that it is more likely of North Asian origin. The results based on autosomal data do not support the hypothesis of Southeast Asian origin which was proposed by Tuner 2nd (1976)4. In addition, PCA revealed that two modern Japanese are located between mainland Asian populations and Jomon populations, consistent with the notion that they are the descendents of the admixture of mainland Asians and Jomons (Figure 3B). Furthermore, the clustering of Jomon populations inferred from Hondo and Ryukyuan Japanese suggested that their respective Jomon components were of similar, if not identical, origins (Figure 3A &B).
Figure 3: Genetic affinities between Jomon and other Asia populations.
Figure 3
A. NJ tree based on pairwise genetic distance. Each inferred Jomon population was named in population IDs of its admixed descendants and continental donors (JOMON ML-NH, JOMON ML-SH, JOMON ML-NHK, JOMON RK-NH, JOMON RK-SH and JOMON RK-NHK, respectively). B. Populations presented on a 3D plot with axis of PC1, 2 and 3 from PCA analysis. Features of the genetic affinities were the same as those were discovered by NJ tree.
Through the estimations and inferences presented above, this study may shed light on the understanding of peopling of Japan. A few critical issues related to the findings of this work need to be further scrutinized.
Our result suggested D2 lineage of Y chromosome provides insufficient information on Jomon's origin. Sharing of haplogroup D-M174 between central Asian populations and Japanese has been recognized as evidence of central Asian origin for paternal lineage of Paleolithic Japanese6. However, this study showed that some populations carrying branches of Y haplogroup D-M174 (D*: 10% in Dai; D1: 7.7% in Chuang, 2.59% in Tujia; D3: 28.89% in Naxi) showed little genetic relationship with the inferred Jomon populations (Figure 3)13. Furthermore, Y haplogroup D-M174 appears rarely in North Asian populations when the populations have a close genetic relationship with Jomon (Figure 3). The only appearance of D2 lineage in Japanese and the widespread geographic distribution of D-M174 made it practically impossible to pinpoint a population in the continent that provided the D2 lineage to Japanese. In contrast, autosomal markers indeed provide additional information that connects Jomon and North Asians.
In this study, a specified model was used to evaluate genetic admixture in modern Japanese populations. However, there is another powerful approach that was commonly applied in data analysis for population admixture, Bayesian method implemented in STRUCTURE. The Bayesian method focuses on a genetic inheritance model specified in terms of the proportion of an individual's genome originating from each of a set of possible subpopulations21. The method is powerful and well recognized. However, when population history is partially understood and the divergence among ancestral populations is relatively small, performance of the Bayesian method is not fully clarified yet22. We applied the Bayesian method on 4 Japanese populations and 9 other East Asian populations with assumption that all the populations shared 2, 3, or 4 independent ancestry populations (Figure 4). None of inferred genetic components from STUCTURE could well explain the great frequency difference of Japanese specific Y lineages, D2 and C1, between modern Hondo Japanese and Ryukyuans, while our estimations were concordant with the previous reports (Figure 2 & 3). The comparison suggested a specified model could be superior when population history was partially known.
Figure 4: Estimated admixtures with different pre-given value for number of genetic components in STRUCTURE 2.3.
Figure 4
Geographic distribution of lineages explained the great contribution of Yayoi in our results. Hammer et al. investigated geographic distribution of Y lineages in Japanese populations. Haplogroup frequencies of the Y lineages showed U-shape cline with significant correlation with geographic distance of the populations from Kyushu. In briefs, the frequency of D2 lineage increased with increase of the distance meanwhile frequencies of O lineages decreased6. The O lineages were recognized as a Yayoi founding lineage and D2 lineage was believed to be Jomon specific6,23. Therefore, the pattern of geographic distribution of lineages supported published archeological and anthropological results about population expansion during Jomon and Yayoi period in Japan. The archeological studies suggested general demographic density was significantly greater in eastern Japan compared to western Japan around the 3,300 years BP and a rapid increase first happened in West Japan around 2,000 years BP24. The studies of physical anthropology on human skeleton showed the new continental immigrants in West Japan, Yayoi people, have better capability to achieve enough foods to feed more people than Jomon24,25. The pattern of population expansion may explain the great genetic contribution (about 60–72%) of Yayoi in extent Japanese. Size of continental immigration was not necessary to be very large but descendants of the immigrants increased rapidly and subsequently dispersed from West Japan to other regions. Population admixture between the continental descendants (Yayoi) and Jomon descendants shaped genetic pattern of extent Japanese. Straits between Japanese islands and Asian mainland may not act as effective barriers to the genetic admixture.
This study supplied a genetic view for peopling of Japan. Both contributions and genetic affinity of Paleolithic Jomon were investigated in quantitative approach. However, the results should be improved continuously in further analysis. At first, the demographic model shall be improved when more data become available across Eurasia, especially from East Asia. Any improvement for the demographic model will lead to better estimation and inference in the model-based approach. The second, the used divergence time between historical Jomon and continental Yayoi should be validated with increased lines of evidence in future although both archeological evidences and genetic studies supported a divergence time between Jomon and continental populations is properly around 20,000 years BP5,6. Furthermore, relatives of Yayoi in Asian mainland should be specified further.
Genotype data
This study involves 94 populations from worldwide, mostly Asia. Genotype data of these populations were collected from three sources, Pan-Asia SNP project26, the International HapMap project27, and Human Genome Diversity Project (HGDP)28. In the Pan-Asia SNP project, DNA samples from 1,719 unrelated individuals of 71 representative populations from China, India, Indonesia, Japan, Malaysia, the Philippines, Singapore, South Korea, and Thailand etc. were collected and genotyped in Affymetrix platform26. Genotypes for 60 unrelated European-Americans (CEU), 60 unrelated Yoruba (YRI), 45 unrelated Chinese (CHB), and 44 unrelated Japanese (JPT) were downloaded from the website of International HapMap project. Furthermore, the HGDP data was obtained from website of Stanford Human Genome Center for genotypes of 240 individuals of 17 East Asia populations and 45 individuals of 2 Native American populations. Finally, 20,362 SNPs with average spacing of 134.8 kb shared among all the 94 populations were included for further analyses. Names of populations, population IDs, sample sizes and more details could be found in online material (see S1 of Supplementary file).
Admixture model
A genetic model (Figure 1) including two parental populations (P1 and P2) and one admixed population (Ph) is frequently used to evaluate contribution of historical genetic donors (population P1′ and P2′) to the population with admixture (Ph)22,29. The P1′, P2′ and Ph' are ancestral populations to P1, P2 and Ph, respectively at tAMD generations before present when the parental populations P1′ and P2′ admixed and led to emergence of Ph′ . P1′ and P2′ contributed to Ph′ with the proportion of λ and 1 - λ, respectively. All the populations have a common ancestral population, P0, at the divergence of the two parental populations, P1′ and P2′. Time of the divergence is tDIV generations before the admixture event. Each population in each historical stage have effective population size Nj, j {1, 2, h, 1′, 2′} (see Figure 1 for detail). Samples (in sizes of S1, S2 and Sh) were collected from the three currently observable populations (P1, P2 and Ph). In Wright-Fisher model on assumption of Hardy-Weinberg Equilibrium (HWE), probability of the observation in samples can be calculated using Bayesian theorem when all demographic parameters are known.29
Estimating historical genetic contribution
Likelihood method was applied on the aforementioned demographic model for parameter estimation29. Wang's method, implemented in LEADMIX, estimates multiple demographic parameters simultaneously using genotype data from the parental informative populations (P1 and P2) and the admixed descendants (Ph). In this study, however, the genotypes on one of the parental populations, i.e. Jomon, is unavailable since none of the modern Japanese populations could be used as pure descendants of Jomon without admixture with Yayoi people. LEADMIX neither was evaluated for its performance for the scenarios with missing parental population, not it could handle thousands of markers simultaneously. Therefore, we developed another maximum likelihood (ML) approach to estimate the contribution of the missing parental population.
The basic idea of ML method is to maximize the probability of observations with an appropriate value for genetic contribution λ. For a specific locus j, the observed counts of a given allele are Cj2 and Cjh in samples from population P2 and Ph, respectively. Given the demographic parameters , the probability of observation on locus j could be calculated as bellows where Here, {fk|k = 0, 2, h, 2′, h'} is allele frequency of the given allele in a specific population k. Effective population sizes are given in {Nk|k = 0, 2, h, 2′, h'}.
With n independent loci or loci with ignorable linkage disequilibrium, we have probability of observations on the n loci Thus, genetic contribution λ can be estimated by maximizing the probability of observations using the ML approach.
During the calculation for probability of observations, allele frequencies in descendant populations were determined by allele frequency in ancestry population P0 and other given demographic parameters, {ω|S2, Sh, N2, Nh, N1′, N2′, λ}, in the Wright-Fisher model. The allele frequency in common ancestral population P0 could be determined by either coalescence theory or uniform distribution with range from 0 to 122,29,30,31. However, joint frequency spectrum of given alleles in descendent populations (P1′, P2′, Ph', P1, P2 and Ph) is difficult to be presented in closed form. We utilized a forward Monte Carlo (MC) simulation to obtain the joint frequency spectrum and calculate the probability of observations.
To maximize the probability of observations, an algorithm of golden section search was implemented with the aforementioned probability calculation. The algorithm finds the extremum of probability by successively narrowing the range of genetic contribution λ32. In other words, we seek a genetic contribution λ given the best explanation to the observations. We executed the search algorithm for multiple times on independent data sets of the same populations to reduce uncertainty of the MC calculation. Median of the optimized results supplies a robust estimation of genetic contribution λ from results of the multiple runs. The two-side 95% confidential intervals of the median are given by order statistics33. Evaluation on simulation data showed that our approach was accurate in multiple scenarios and robust to ascertain bias of marker allele frequency (see S2 and S3 of Supplementary file).
Estimating contribution of Jomon
Parameters of the demographic model (Figure 1), except genetic contribution λ, must be given before further admixture analysis using aforementioned ML method.
The estimated time of divergence between Jomon and their continental relatives is 14,000-30,000 years B.P., properly around 20,000 years B.P. (based on coalescent time of Y haplogroup M174-D2)5,6. The arrival of Yayoi people and the admixture of Yayoi and Jomon occurred about 2,0002,500 years BP9. We therefore let tDIV = 1,000 and tAMD = 100 generations in subsequent analyses. The rapid accumulation of genetic data improves the reliability of demographic model of human populations. Based on fitness of allele frequency spectrum of simulation data and multi-locus sequencing data, Schaffner et al. identified an optimized demographic model including Han Chinese and Japanese34. The best fitted demographic model with its parameters have been well supported and widely applied in genetic studies35,36,37,38,39. Thus, we employed the parameters of population dynamics described in Schaffner et al (2005) in our admixture estimation (table 1).
Table 1: Demographic parameters of the best fitted model for East Asia populations
In each estimation, 30 SNP sets were involved, each with 500 SNPs randomly selected with replacement from 20,362 SNPs. The contribution of Jomon to extant Japanese populations was estimated using all 30 groups individually and the median of the estimations was taken as the overall estimation.
Inference of allele frequency of the missing parental population
In order to explore genetic affinity of Jomon with the extant populations, we estimated allele frequency of each SNP in Jomon population using an ML method. Given a genetic contribution λ and current observation Cj2 and Cjh on locus j for population P2 and Ph, allele frequency fj1′ in the missing ancestral population P1′ could be estimated when the recent effective population sizes (Nh and N2) are large and the admixture event is relatively young. Details of the estimation were addressed below.
Given the current observation Cj (Cj2, Cjh) and sample size S (S2, Sh), we have the probability of observation where
In order to maximize the probability, we let partial derivatives of Equation 4 to be zero. After solving the partial derivative equations, we have estimation for the allele frequency in missing parental population fj1 by
Discovery of Genetic Relationships
With the estimated genetic contributions of Jomon in Ryukyuans and Hondo Japanese, we inferred the allele frequencies of corresponding markers of Jomon populations using genotype data of Ryukyuans (JP_RK), Hondo Japanese (JP_ML) and all the three possible genetic sources (NH, SH and NHK). Allele frequencies of Jomon were inferred separately utilizing pairs of the data (JP_RK and NH, JP_RK and SH, JP_RK and NHK, JP_ML and NH, JP_ML and SH, JP_ML and NHK) in this study. Using the inferred frequencies, we explored genetic relation between Jomon and other Asian populations.
The coancestry coefficient is a measure of genetic distance and the coefficient determined by drift only is proportion to divergence time of pairwise populations20. We calculated the coancestry coefficient to uncover pairwise genetic distance between Jomon and other Asian populations. Based on the genetic distances, NJ tree was built to present possible genetic affinities in program Splits Tree 4.040. All mordent Japanese populations and Korean were excluded from the NJ tree to avoid possible bias because coancestry coefficient was not originally proposed to handle such admixed populations. Simultaneously, Principle Component Analysis (PCA) was used to visualize genetic affinity based on direct difference of the allele frequencies of all populations. The PCA analysis was conducted in Matlab language and computational environment (version 2007b).
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We thank anonymous reviewers for comments which improved the study and the manuscript. Y.H. gratefully acknowledges the support of SA-SIBS scholarship program. This work was supported by grants from Shanghai Institutes of Biological Sciences (2010KIP206 to Y.H.) and National Natural Science Foundation of China (81100997 and 31171279 to Y.H.; 30890034 and 30625016 to L.J.). L.J. was also supported by Shanghai Leading Academic Discipline Project (B111) and the Center for Evolutionary Biology at Fudan University. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Author information
1. Chinese Academy of Sciences and Max Planck Society (CAS-MPG) Partner Institute for Computational Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
• Yungang He
• , Wei R. Wang
• , Shuhua Xu
• & Li Jin
• Yungang He
• , Wei R. Wang
• , Shuhua Xu
• & Li Jin
3. Ministry of Education Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai 200433, China
• Li Jin
4. See end of paper for details.
• Pan-Asia SNP Consortium
1. Search for Yungang He in:
2. Search for Wei R. Wang in:
3. Search for Shuhua Xu in:
4. Search for Li Jin in:
5. Search for Pan-Asia SNP Consortium in:
H.Y. and W.W. carried out the studies and performed the statistical analysis. H.Y. and J.L. designed the study. H.Y., J.L. and X.S. participated in its coordination and helped to draft the manuscript. Members of Pan-Asia SNP Consortium conceived the data production and participated in its coordination. All authors read and approved the final manuscript.
Competing interests
The authors declare no competing financial interests.
Corresponding authors
Correspondence to Yungang He or Li Jin.
Supplementary information
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Supplementary Information
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About this article
Publication history
The Pan-Asian SNP consortium authorship list
China: ChineseNational HumanGenome Center at Shanghai: Wei Huang (Project Leader), Ying Wang,Wentao Yuan,HaifengWang, Guoping Zhao (Principal Investigator); Institute of Medical Biology, Chinese Academy of Medical Science: Jiayou Chu; National Engineering Center for Biochips at Shanghai: Huasheng Xiao, Junsong Han; School of Life Sciences, Fudan University; CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences: Li Jin (Principal Investigator), Shuhua Xu (Project Leader). India: Institute of Genomics and Integrative Biology: Mitali Mukerji (Project Leader), Amit Sinha, Vinod Scaria, Amit Chaurasia,, Pankaj Jha, Ikhlak Ahmed, Indian Genome Variation Consortium, Samir K. Brahmachari (Principal Investigator); Indian Statistical Institute (Kolkata): Partha P. Majumder; The Centre for Genomic Applications: Kiran Kumar Mandapati, Preeti Khurana. Indonesia: Eijkman Institute for Molecular Biology: Herawati Sudoyo (Project Leader), Yuliana Sandraling, Helena Suryadi, Sangkot Marzuki (Principal Investigator). Japan: Health Sciences University of Hokkaido: Norio Niikawa; National Institute of Genetics: Takashi Gojobori (Principal Investigator), Yoshiyuki Suzuki, Tomohiro Koike; RIKEN Genomic Sciences Center: Yoshiyuki Sakaki (Principal Investigator); Tokai University School of Medicine: Akira Oka, Hidetoshi Inoko; University of the Ryukyus: Kenji Naritomi; University of Tokyo, School of Medicine: Katsushi Tokunaga (Principal Investigator), Nao Nishida, Jun Ohashi, Ryosuke Kimura, University of Tokyo, Graduate School of Frontier Science: Sumio Sugano (Principal Investigator). Korea: Eulji University College of Medicine: Kuchan Kimm; Korea National Institute of Health: Jongsun Jung (Project Leader), Bermseok Oh, Jongyoung Lee, Kwangjoong Kim, Hyung-Lae Kim (Principal Investigator), Korean Bioinformation Center, Korean Institute of Bioscience and Biotechnology: Ho Ghang (Project Leader), Woo-Yeon Kim, Sunghoon Lee, Jin Ok Yang, Sangho Oh, Hyang Sook Yoo, Jong Bhak (Principal Investigator); Soongsil University: Sangsoo Kim. Malaysia: University of Malaya: Maude Elvira Phipps (Principal Investigator), Timothy Adrian Jinam, Juli Edo,Mahmood Ameen Abdulla; Universiti Sains Malaysia: Bin-Alwi Zilfalil (Principal Investigator), Hoh Boon Peng, Mohd Ros Sidek. Philippines: Natural Sciences Research Institute, University of the Philippines, Diliman: Maria Corazon A. De Ungria (Project Leader), Gayvelline C. Calacal, Frederick C. Delfin, Henry B. Perdigon, Jazelyn M. Salvador, Kristina A. Tabbada, Lilian P.Villamor; Institute of Human Genetics, University of the Philippines,Manila: Eva Maria C. Cutiongco-de la Paz, Carmencita D. Padilla (Principal Investigator). Singapore: Genome Institute of Singapore: Mark Seielstad (Principal Investigator), Vikrant Kumar, Jieming Chen, Wayne Mitchell, Rick Ong, Eileen Png, Adrian Tan, Edison T. Liu (PASNPI Project Leader); National University of Singapore: Poh-San Lai Taiwan: Institute of Biomedical Sciences, Academia Sinica: Chien-Hsiun Chen (Principal Investigator), Yuan-Tsong Chen, Jer-Yuarn Wu, Sheng-Feng Ho. Thailand: Chiang Mai University: Daoroong Kangwanpong (Principal Investigator), Metawee Srikummool, Jatupol Kampuansai; National Center for Genetic Engineering and Biotechnology: Prasit Palittapongarnpim (Project Leader), Sissades Tongsima, Chumpol Ngamphiw, Supasak Kulawonganunchai; Mahidol University: Suthat Fucharoen (Project Leader), Anunchai Assawamakin. USA: Affymetrix: Giulia C. Kennedy (Principal Investigator), Eric Wang; John Hopkins University: Yin Yao.
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Mountain Hare
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The mountain hare (Lepus timidus scoticus) is genuinely native to the UK, unlike the more common Brown Hare or even the rabbit, both of which are introduced species. The mountain hare is smaller than the Brown Hare and its coat turns white in winter, one of the few UK species to display this behaviour. Their population appears to be declining though they are not uncommon in certain mountainous parts of Scotland.
The Mountain Hare is an iconic species, and like the Brown Hare it has been revered and protected in ancient times as a mystical, almost supernatural animal. In the 18th and 19th centuries, hare (both brown and mountain) was a prized meat and eaten in country areas and available in town and city markets. Nowadays it is seen seldom in restaurants and is generally unavailable to the public unless there are contacts with the estates that cull the hares.
It inhabits in remote, inhospitable landscapes and seen only by those prepared to make the effort to climb rough mountainous terrain. In terms of culinary use, a few game suppliers in Scotland can supply Mountain Hare, so it can get into the food chain, but it is very uncommon. If it does appear on menus, restaurants seldom identify the species.
Mountain hares were previously abundant in higher ground across the UK, but only exist now in certain mountainous parts of Scotland so over many years there has certainly been a significant reduction in the total population. The Mountain Hare is notoriously difficult to count, recent assessments only being able to confirm that its distribution within Scotland is stable. It can breed for a large part of the year and can produce three litters every year so if conditions are favourable, it can multiply quite quickly. There is a known historic ten-year cycle of rise and fall in population, believed to be related to a gut parasite disease which affects the fertility of the female hare. The total population has not been measured for some years, though a survey is underway this year. Natural predators include eagles, foxes and stoats, but man is by far the greatest threat to the population. Though the Mountain Hare is uncommon, it is not believed to be under threat of extinction.
They live in sub-alpine scrub, but also thrive on grouse moors. There is a complex relationship between the two species as both are host to ticks, which spread a variety of diseases. The Mountain Hares are largely immune to the diseases, (though anecdotal evidence suggests this may no longer be the case) but the grouse are severely affected by louping-ill virus, spread by ticks. As a result, the grouse estates launch massive culls of hares to protect their investment in grouse shooting, often with over 1,000 hares killed in a day. Although in some cases the carcasses are sent to game dealers, there is also evidence that this may not be commercially worthwhile, and piles of hare carcasses are left to rot.
In conclusion, there is a bit of a dilemma. Should the Mountain Hare be protected by regulating culls? Or should we accept that inevitably there will be killing to protect the competing grouse (already in the Ark of Taste), and instead ensure that those Mountain Hares that are killed are used productively in the food chain. Subject to the surveys confirming a sustainable population, the latter seems the better option.
In recent times, it has received some protection as in Scotland there is a defined close season, 1st March to 31st July. Most culls take place in late winter/early spring when hares are highly visible against terrain if the snow has melted, which is before the breeding season. However permission to kill during the closed season appears not hard to get.
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StateUnited Kingdom
Scottish Highlands
Other info
Breeds and animal husbandry
Nominated by:Walter Mowat
Arca del GustoThe traditional products, local breeds, and know-how collected by the Ark of Taste belong to the communities that have preserved them over time. They have been shared and described here thanks to the efforts of the network that Slow Food has developed around the world, with the objective of preserving them and raising awareness. The text from these descriptions may be used, without modifications and citing the source, for non-commercial purposes in line with the Slow Food philosophy.
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3.2 City as Form and History
The soul of the city becomes the city’s history… the city’s distinctive and definitive character, its memory… one can say that the city itself is the collective memory of its people” (Rossi 1982; p.130)
If people define a city, then the memory of those people and the impact of numerous lives across the history of a city acts to shape the form that city takes. Aldo Rossi defines the city as both its form, architecture and structure as well as the embedded history of memory that characterises that form. The city’s character is formed by the collective memory that feeds into the artefacts of the city, the build up of significance through each use and function of its buildings. Memory flows through a city on a submerged level, shaping its form and artefacts and the idea we have about those (Rossi 1982; p.130-131). The founding of the city is the city’s mythology, perhaps it is a set plan as Kostof suggests but it is one that has become blurred into fiction as the memory of it hazes over time. The original themes of the city persist but they are also modified and re-rendered through each development. A city by its name is a physical space but also the various notions, experiences, ideas associated with that city.10
10 “With time, the city grows upon itself; it acquires a consciousness and memory. In the course of its construction, its original themes persist, but at the same time it modifies and renders these themes of its own development more specific. Thus, while Florence is a real city, its memory and form come to have values that are also true and representative of other experiences. At the same time, the universality of these experiences is not sufficient to explain the precise form, the type of object which is Florence.” Rossi, A. (1982). The Architecture of the City. p.21
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SPRI Home About SPRI
Alvit, Dieldrite, Illoxol
SPRI Emission Reporting Threshold
1.00 Kg/yr Pollutant Emissions to Air
0.0005 Kg/yr Pollutant Emissions to Water
0.0005 Kg/yr Pollutant Emissions to Waste Water
1.00 Kg/yr Pollutant Emissions to Land
What is it?
Under normal conditions, pure Dieldrin is white crystals, which have a faint chemical smell. It often contains impurities, which give it a beige colour and possibly also a stronger smell. Dieldrin evaporates easily. In its pure form, it melts at 176 degrees celsius, but impure forms have a lower melting point of around 95 degrees celsius. Dieldrin does not dissolve in water, but readily mixes with organic (carbon-containing) solvents, fats and oils. Dieldrin is part of the "drin" group of pesticides and therefore has similar properties to other members of the group such as Endrin, Aldrin and Isodrin.
What is it used for?
In the past, Dieldrin was widely used as a pesticide to control insects in soils and also to control insects carrying disease (such as malarial mosquitoes). Its use has now been banned in many countries (including the UK). It may however still be used in some developing countries - mainly as an agricultural pesticide, but also to control pests in wood and textiles.
Where does it come from?
In countries where it is still used, releases of Dieldrin occur as a result of its manufacture, transport and use as a pesticide. It is also formed when the chemically similar Aldrin is broken down in the environment. There are not thought to be any natural sources of Dieldrin to the environment.
How might it affect the environment?
Dieldrin is highly toxic to aquatic organisms and many other forms of wildlife and can accumulate in the environment, particularly in the fat of animals. Dieldrin binds strongly to soil particles and is not easily broken down. Little seeps to groundwaters. That which evaporates from soils into the atmosphere may travel considerable distances before being re-deposited elsewhere. Dieldrin is classed as a "persistent organic pollutant" (POP). The effects of Dieldrin pollution cause concern at a global as well as local level.
How might exposure to it affect human health?
Dieldrin can enter the body inhalation of air containing dieldrin, ingestion of contaminated water or food or by dermal contact with dieldrin. Exposure to dieldrin occurs mainly by ingestion of contaminated food. Inhalation of moderate levels of dieldrin over long periods of time can cause a range of adverse health effects including headaches, dizziness, uncontrollable muscle movements irritability, and vomiting. Exposure to high levels can cause convulsions and kidney damage. Ingestion of dieldrin can cause nausea vomiting and diarrhoea. Ingestion of large quantities of dieldrin can result in symptoms similar to those for inhalation and in extreme cases death. Dermal contact with high levels of dieldrin can cause skin irritation. Aldrin converts to dieldrin once inside the body therefore exposure to aldrin can also result in elevated dieldrin levels in the body. The International Agency for Research on Cancer has designated dieldrin as being not classifiable as to its carcinogenicity to humans. However, exposure to dieldrin at normal background levels is unlikely to have any adverse effect on human health.
What steps are being taken to limit the potential impacts?
Dieldrin is a UK Red List pollutant because of concern about its harmful impacts on the environment and human health. Releases of Dieldrin are controlled through the Food and Environmental Protection Act (FEPA 1985) and the Control of Pesticides Regulations (COPR 1986). Its use is now banned in the EU. European Directives regulating levels of Dieldrin include that concerned with the marketing and use of certain dangerous chemicals (79/117/EEC) and that concerned with pollution of the aquatic environment (76/464/EEC). At an international level, Dieldrin is the subject of two proposed UN treaties, is banned under the UNECE POPs protocol and proposed for elimination under the UNEP POPs Convention. Dieldrin is also listed as a candidate substance under the OSPAR Convention which protects the marine environment of the north-east Atlantic Ocean.
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Posted on
Wings of Wax and Feathers: The Myth of Icarus and Avian Symbolism
During my research for the annotated bibliography, I stumbled upon an article discussing the use of the Icarus myth in Romantic poetry. According to the abstract, the myth of Icarus is used as an archetype for the Romantic genius; and invokes the motifs of soaring, falling, birds, and wings; and portrays these themes as supernatural phenomena to create a sense of the sublime. I thought that the subject matter of the poems in Thursday’s class, particularly “To a Sky-Lark” could stand to be examined in this fashion.
Here is a brief summary of the myth for those who are unfamiliar with it: In order to escape imprisonment, Daedalus, a skillful artisan, crafts wings out of wax and feathers for himself and his son, Icarus, so that they may fly over the sea and escape. Daedalus cautions Icarus to neither fly too high, for the sun would melt the wax, nor too low, for the sea foam would soak the feathers. However, the prideful Icarus flies too close to the sun and the wax melts, causing Icarus to fall into the sea and drown.
In Percy Shelley’s poem “To a Sky-Lark”, one is immediately confronted with Icarian symbolism by the title of the poem, which is dedicated to a bird, and by the first stanza:
“Hail to thee, blithe Spirit!
Bird thou never wert-
That from Heaven or near it
Pourest thy full heart
In profuse strains of unpremeditated art”
In lines one and three, Shelly describes the sky lark in supernatural terms, referring to it as a “spirit” which is either “from heaven or near it”. And from lines two, four, and five we learn that the bird Shelly is referring to is in fact not a bird at all, and then Shelly makes an allusion to Milton, who is apparently the poetic genius that Shelly is revering in this poem.
The second stanza refers to the myth as well in lines one and two: “Higher still and higher/ from the earth thou springest”. However, unlike Icarus, the poet does not fall to his death: “And singing still dost soar, and soaring ever singest”. The motif of soaring is also referred to later in the poem as a “scorner of the ground”.
Throughout the poem, the sky lark continues to be described in supernatural terms, such as a sprite, or a dreamer of dreams that mortals cannot comprehend, and several of the poem’s stanzas are similes that attempt to describe it in different ways. This sort of beauty and awe that defies description contributes to the poem’s sense of sublimity.
Of course, Shelley is not the only one to use these thematics, as we have seen in the poetry of Clare and even Byron when he mockingly refers to Southey as a flying fish flopping on the deck. Invoking this myth also outlived the Romantic movement as well: James Joyce uses the name Daedalus as the surname of the protagonist in A Portrait of the Artist as a Young Man.
One response to “Wings of Wax and Feathers: The Myth of Icarus and Avian Symbolism
1. Alex
This explains why I was suddenly reminded of Joyce’s The Portrait of the Artist as a Young Man while reading this — I had no idea why it popped into my head but, well, now I know.
I also find it a strange coincidence that Shelley loved Milton, since it would come to pass that the monster in his wife’s novel (Mary Shelley’s Frankenstein) would later be compared to Milton’s depiction of Satan in his book Paradise Lost.
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Shapes of Space: Hyperbolic Space
Hyperbolic Space
The hyperbolic plane is a strange surface. While a sphere, being finite, is smaller than a normal plane (which is infinite), a hyperbolic plane is larger. This is hard to imagine at first. Rucker explains how to think about the hyperbolic surface of pseudosphere:
"To begin to get the notion of a pseudosphere, you might think about crawling around on an endless taffy plane. Every few feet you stop to grab and stretch the plane's material. It gets baggy and wrinkled...more and more spacious." (p. 103)
A pseudosphere is a difficult object to draw, since we usually only have a flat plane available as a drawing surface. (7) Rucker uses a clever method to depict a pseudosphere. He first shrinks an ordinary plane to fit inside a small space, then he does the same with a hyperbolic plane.
It is also possible to illustrate a piece of a hyperbolic plane.
Hyperbolic space is the three-dimensional equivalent of the hyperbolic plane. Hyperbolic space is more roomy than ordinary space, but if you were to visit a hyperbolic universe, you would think that everything in the entire universe was very close to you! How can this be?
Light in hyperbolic space travels in a path that you perceive as curved, though it is actually straight according to the geometry of the space. In order to look at a distant object in the hyperbolic universe, you have to cross your eyes. Your brain is accustomed to images from ordinary space and interprets your crossed eyes as evidence that the object is very close to your face.
Since we do not think everything in our universe is nearby, how can hyperbolic space be a possible shape for our universe? The hyperbolic curvature may be slight enough that we have not yet detected it.
Next: Notes and References
Table of Contents
Send comments or questions to Lisa Eckstein
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Missing Link? What the Piltdown Man Hoax Can Teach Science Today
In 1912 Arthur Smith Woodward, a paleontologist with the Natural History Museum, and Charles Dawson, an amateur antiquarian, reported the discovery of a new species of early human at Piltdown in England which they believed could date back one million years. It was given the name Eoanthropus dawsoni.
Credit: Courtesy Wikimedia
In 1912, Charles Dawson, an amateur archaeologist in England, claimed he'd made one of the most important fossil discoveries ever. Ultimately, however, his "Piltdown Man" proved to be a hoax. By cleverly pairing a human skull with an orangutan's jaw – stained to match and give the appearance of age – a mysterious forger duped the scientific world.
In the decades between the find's unearthing and the revelation it was fraudulent, people in the United States and around the world learned about Piltdown Man as a "missing link" connecting ape and man. Newspaper articles, scientific publications and museum exhibitions all presented Piltdown Man as a legitimate scientific discovery supporting a particular vision of human evolution.
Historians, science writers and others have investigated the Piltdown Man controversy over the years, shedding new light on the fraud. As we reconsider the nature of "facts," "fake news" and knowledge production, it's worthwhile to revisit the Piltdown Man episode.
"Regrettably… the specimen was not yet available for examination by outsiders, and so no original opinion can be given concerning its status. It represents doubtless one of the most interesting finds relating to man's antiquity, though seemingly the last word had not yet been said as to its date and especially as to the physical characteristics of the being it stands for."
It ultimately took until the later decades of the 20th century for the Piltdown bones to be fully discredited. The hoax was likely created by Dawson himself, though who exactly concocted the scam is still debated – "Sherlock Holmes" author Arthur Conan Doyle's name has even been mentioned as a possible perpetrator.
As Berkeley anthropologist Sherwood Washburn offered in a letter, "My opinion is that if more people had seen the originals sooner the fake would have been recognized." Confusion had arisen because so few scholars were granted access to the original evidence.
Part of what finally put Piltdown Man to rest was the nature of new discoveries emerging. They informed researchers' developing understanding of the human past and began turning much scientific attention away from Europe toward Asia and Africa.
Consider a 2003 find from Indonesia that was as shocking as the discovery of Piltdown Man: a nearly complete female skeleton researchers suggested was from a tiny human ancestor they called Homo floresiensis (commonly nicknamed "hobbit"). Media speculation ran wild early on about this new species added to our family tree, but paleoanthropology has evolved a great deal since Piltdown Man.
Homo floresiensis are likely a genuinely groundbreaking discovery – hopefully the more transparent way the research unfolded makes this easier to untangle than Dawson's claims a century ago. Thoughtful collaboration, making data available openly, more effective popular science communication and multiple channels of accurate information may help us better respond to the next Piltdown Man.
Samuel Redman, Assistant Professor of History, University of Massachusetts Amherst
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Salar De Uyuni
Salar de Uyuni 2
Formation, Geology and Climate
Salar de Uyuni is part of the Altiplano of Bolivia in South America. The Altiplano is a high plateau, which was formed during uplift of the Andes mountains. The plateau includes fresh and saltwater lakes as well as salt flats and is surrounded by mountains with no drainage outlets.
The geological history of the Salar is associated with a sequential transformation between several vast lakes. Some 30,000 to 42,000 years ago, the area was part of a giant prehistoric lake, Lake Minchin. Its age was estimated from radiocarbon dating of shells from outcropping sediments and carbonate reefs and varies between reported studies. Lake Minchin (named after Juan B. Minchin of Oruro) later transformed into paleolake Tauca having a maximal depth of 140 meters (460 ft), and an estimated age of 13,000 to 18,000 or 14,900 to 26,100 years, depending on the source. The youngest prehistoric lake was Coipasa, which was radiocarbon dated to 11,500 to 13,400 years ago. When it dried, it left behind two modern lakes, Poopó Lake and Uru Uru Lake, and two major salt deserts, Salar de Coipasa and the larger Salar de Uyuni. Salar de Uyuni spreads over 10,582 square kilometers (4,086 sq mi), which is roughly 100 times the size of the Bonneville Salt Flats in the United States. Lake Poopó is a neighbor of the much larger Lake Titicaca. During the wet season, Titicaca overflows and discharges into Poopó, which, in turn, floods Salar De Coipasa and Salar de Uyuni.
Salar de Uyuni 3
Lacustrine mud that is interbedded with salt and saturated with brine underlies the surface of Salar de Uyuni. The brine is a saturated solution of sodium chloride, lithium chloride and magnesium chloride in water. It is covered with a solid salt crust varying in thickness between tens of centimeters and a few meters. The center of the Salar contains a few “islands”, the remains of the tops of ancient volcanoes submerged during the era of Lake Minchin. They include unusual and fragile coral-like structures and deposits that often consist of fossils and algae.
The area has a relatively stable average temperature with a peak at 21 °C (70 °F) in November to January and a low of 13 °C (55 °F) in June. The nights are cold all through the year, with temperatures between −9 and 5 °C (16 and 41 °F). The relative humidity is rather low and constant throughout the year at 30 to 45%. The rainfall is also low at 1 to 3 millimeters (0.039 to 0.118 in) per month between April and November, but it may increase up to 70 millimeters (2.8 in) in January. However, except for January, even in the rainy season the number of rainy days is fewer than 5 per month.
Economic Influence
The Salar contains large amounts of sodium, potassium, lithium and magnesium (all in the chloride forms of NaCl, KCl, LiCl and MgCl2, respectively), as well as borax. Of those, lithium is arguably most important as it is a vital component of many electric batteries. With estimated 9,000,000 tonnes (8,900,000 long tons; 9,900,000 short tons), Bolivia holds about 43% of the world’s lithium reserves; most of those are located in the Salar de Uyuni.
Lithium is concentrated in the brine under the salt crust at a relatively high concentration of about 0.3%. It is also present in the top layers of the porous halite body lying under the brine; however the liquid brine is easier to extract, by boring into the crust and pumping out the brine. The brine distribution has been monitored by the Landsat satellite and confirmed in ground drilling tests. Following those findings, an American-based international corporation has invested $137 million to develop lithium extraction. However, lithium extraction in the 1980s and 1990s by foreign companies met strong opposition of the local community. Despite their poverty, locals believed that the money infused by mining would not reach them.
There is currently no mining plant at the site, and the Bolivian government does not want to allow exploitation by foreign corporations. Instead, it intends to build its own pilot plant with a modest annual production of 1,200 tonnes (1,200 long tons; 1,300 short tons) of lithium and to increase it to 30,000 tonnes (30,000 long tons; 33,000 short tons) by 2012.
Salar de Uyuni is estimated to contain 10 billion tonnes (9.8 billion LT; 11 billion ST) of salt, of which less than 25,000 tonnes (25,000 long tons; 28,000 short tons) is extracted annually. All miners working in the Salar belong to Colchani’s cooperative.
Because of its location, large area and flatness, the Salar is a major car transport route across the Bolivian Altiplano, except when seasonally covered with water.
Salar de Uyuni 4
Salar is salt flat in Spanish. Uyuni originates from the Aymara language and means a pen (enclosure); Uyuni is also the name of a town that serves as a gateway for tourists visiting the Salar. Thus Salar de Uyuni can be loosely translated as a salt flat with enclosures, the latter possibly referring to the “islands” of the Salar; or as “salt flat at Uyuni (the town named ‘pen for animals’)”.
Aymara legend tells that the mountains Tunupa, Kusku and Kusina, which surround the Salar, were giant people. Tunupa married Kusku, but Kusku ran away from her with Kusina. Grieving Tunupa started to cry while breast-feeding her son. Her tears mixed with milk and formed the Salar. Many locals consider the Tunupa an important deity and say that the place should be called Salar de Tunupa rather than Salar de Uyuni.
Satellite Calibration
Salt flats are ideal for calibrating the distance measurement equipment of satellites because they are large, stable surfaces with strong reflection, similar to that of ice sheets. As the largest salt flat on Earth, Salar de Uyuni is especially suitable for this purpose. In the low-rain period from April to November, due to the absence of industry and its high elevation, the skies above Salar de Uyuni are very clear, and the air is dry (relative humidity is about 30%; rainfall is roughly 1 millimetre or 0.039 inches per month). It has a stable surface which is smoothed by seasonal flooding (water dissolves the salt surface and thus keeps it leveled). As a result, the variation in the surface elevation over the 10,582-square-kilometer (4,086 sq mi) area of Salar de Uyuni is less than 1 meter (3 ft 3 in), and there are few square kilometers on Earth that are as flat. The surface reflectivity (albedo) for ultraviolet light is relatively high at 0.69 and shows variations of only a few percent during the daytime. The combination of all these features makes Salar de Uyuni about five times better for satellite calibration than the surface of an ocean. Using Salar de Uyuni as the target, ICESat has already achieved the short-term elevation measurement accuracy of below 2 centimeters (0.79 in).
With the use of modern GPS technology, it can now be proved that the Salar de Uyuni is not perfectly flat. New measurements revealed previously missed features resembling ridges, hills, and valleys only millimeters in height. They originate from the variation in material density, and thus the gravitational force, beneath the Salar’s sediments. Just as the ocean surface rises over denser seamounts, the salt flat surface also rises and falls to reflect the subsurface density variations.
Salar de Uyuni 5
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Mexico’s War of Reform (1857 – 1861)
On April 6, 1859, the US government officially recognized the Liberal government in Mexico’s War of Reform. Mexico’s War of Reform is part of the long struggle in the 19th century between Liberal and Conservative forces. The Liberals wanted a federalist government that limited that authority of the military and the Catholic Church. The Conservatives wanted a centralist government, with the Church and the military maintaining their traditional roles and powers.
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Spline (mathematics)
Single knots at 1/3 and 2/3 establish a spline of three cubic polynomials meeting with C2 continuity. Triple knots at both ends of the interval ensure that the curve interpolates the end points
In mathematics, a spline is a function defined piecewise by polynomials. In interpolating problems, spline interpolation is often preferred to polynomial interpolation because it yields similar results, even when using low degree polynomials, while avoiding Runge's phenomenon for higher degrees.
In the computer science subfields of computer-aided design and computer graphics, the term spline more frequently refers to a piecewise polynomial parametric curve[citation needed]. Splines are popular curves in these subfields because of the simplicity of their construction, their ease and accuracy of evaluation, and their capacity to approximate complex shapes through curve fitting and interactive curve design.[citation needed]
The term spline comes from the flexible spline devices used by shipbuilders and draftsmen to draw smooth shapes.[1] It also is an acronym for "Smooth Polynomial Lines Interpolating Numerical Estimates".
The term "spline" is used to refer to a wide class of functions that are used in applications requiring data interpolation and/or smoothing. The data may be either one-dimensional or multi-dimensional. Spline functions for interpolation are normally determined as the minimizers of suitable measures of roughness (for example integral squared curvature) subject to the interpolation constraints. Smoothing splines may be viewed as generalizations of interpolation splines where the functions are determined to minimize a weighted combination of the average squared approximation error over observed data and the roughness measure. For a number of meaningful definitions of the roughness measure, the spline functions are found to be finite dimensional in nature, which is the primary reason for their utility in computations and representation. For the rest of this section, we focus entirely on one-dimensional, polynomial splines and use the term "spline" in this restricted sense.
Other Languages
català: Spline
čeština: Spline
Deutsch: Spline
eesti: Splain
español: Spline
Esperanto: Splajno
فارسی: اسپلاین
français: Spline
italiano: Funzione spline
עברית: Spline
қазақша: Сплайн
magyar: Spline
македонски: Сплајн
Nederlands: Spline
norsk: Spline
português: Spline
русский: Сплайн
slovenščina: Zlepek
српски / srpski: Сплајн
svenska: Spline
українська: Сплайн
中文: 样条函数
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/ 0034 616 39 58 80 contact@englishaula.com
How to do the Exercises:
You are given a set of words.
The word will appear in the input box.
Read more
QUESTION: What's the difference between TOWARD and TOWARDS?
These prepositions can be used quite interchangeably and that there is no difference in meaning. The only slight difference in usage is that toward is perhaps more characteristic of American English and towards more usual in British English.
Toward or towards means 'in the direction of':
- Can you see that light over there? I think it is coming towards us.
- There are always more mosquitoes in the air toward evening. Have you noticed?
Read more
INCORRECT SENTENCE: Its Davids dogs bone.
• IT'S
• BONE
• DOGS
• DOG'S
• ITS
• .
Listen and repeat
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Image In Assisi, Italy, the mountaintop town where St. Francis lived in the late 12th and early 13th centuries, a beautiful church from that era has its inside walls painted entirely white. Our guide pointed out that colorful murals originally covered the walls, until the Black Plague swept through in the 14th century. Town officials became convinced that the sickness somehow came from the frescoes' paint, so they ordered the walls whitewashed. Unfortunately, this destroyed most of the murals. Only fragments survive today. Of course, it did nothing about the plague. No one yet realized that plague was spread by rat-borne fleas. The rush to fight the sickness with every possible means not only achieved nothing positive, but caused irreversible damage.
The Black Death was a recurring feature of the cold period called the Little Ice Age - i.e., approximately AD 1300 to 1870. (Other LIA dates can be argued on the basis of temperature minima around 1650, 1770 and 1850 - each separated by slight warming intervals.) We now know the highly contagious plague incubated in unhealthy, overcrowded living spaces - typically in large cities infested with flea-ridden vermin.
In a less technological age, people were only vaguely aware that they lived in a colder time than the previous Medieval Warm Period (AD 900-1300) when food was plentiful and people led healthier, outdoor lives. Occasional measurable indicators - like glacier expansion - showed how cold the LIA was. During the 15th and 16th centuries glaciers began to threaten Alpine villages built during the warm era. Alarmed residents asked the Church to intercede with God to arrest the grinding advance of the great rivers of ice. Priests prayed and incanted, and for a time the ice slowed or even stopped. Later, the ice again advanced until late in the 19th century.
LIA glaciers encroached on Greenland locales where Viking settlers farmed and built villages at the warm era's zenith. Cold weather brought poor harvests, starvation and eventual extinction. Europe-Greenland communication finally ceased during the 15th century, after the Greenland settlements died out. Arctic explorers who "rediscovered" Greenland a century later found only unpopulated remnants of the former settlements. (Until well within my lifetime, scientists had no explanation for what happened to Greenland. We now know it simply froze over.)
In the context of 14th century medical understanding - or lack thereof - stopping the Black Death was impossible. The legendary town of Hamelein came closest to a true solution when it hired the Pied Piper to clean out the rats. (But greed brought the town to grief when it cheated the Piper after he did the job. In retaliation, he lured the town's children away.)
In Assisi, where rats were not yet suspected of complicity in the plague, officials did only harm in their haste to "do something". (Only the whitewashers' union came out ahead.) Alpine church officials might (or might not) have stopped the glaciers' advance, but at least they did no harm.
These are cautionary tales for our time. Clearly, the climate has warmed before - most recently during 1870-1940, when industrialization was far below present levels - and actually cooled during the highly industrialized period, 1940-1980. Despite these facts, a great, crusading wave of environmental activism has now convinced much of the industrialized world (except for growing industrial powers India and China) that carbon dioxide emissions are causing the current warming that began around 1980. Dissenting scientists - some of whom argue that higher sunspot activity produces warming, while lower sunspot activity produces cooling - are vilified and shouted down. Their research funds - and, in some cases, their lives - are being threatened.
Politicians like Al Gore - basking in a new career as a movie star and a "Doom is Nigh" environmental huckster - want new taxes and draconian changes in Americans' lifestyles (excepting their own). Technical businesses are lured by the "dream scenario" of a problem situation that can never be improved, no matter how much is spent on it. Prospective billions in supranational carbon-taxes have visions of world-control - including deconstruction of the world's industrial powerhouse (the USA) - dancing in the heads of United Nations officials.
A cadre of Christian ministers - led by mega-church guru Rick Warren - has joined Al Gore in proclaiming the greenhouse warming science "settled". Preachers who wouldn't know an atom from an electron insist that reducing our "carbon footprint" is a matter of morality and Christian stewardship. Christian debate has shifted from WWJD (What Would Jesus Drive?) to a conviction that Jesus wouldn't drive at all. A primitive lifestyle is being seriously pushed in some circles as the responsible solution to the global warming "crisis". (One wonders how many wives have been consulted about giving up hot showers and air conditioning.)
All but the truest of true-believers in the greenhouse-gas/global-warming story will privately admit that the measures proposed to reduce carbon dioxide cannot cool the climate. This is OK because their aims far exceed climate-cooling. The global-warming story is only the means to convince a gullible public to pay higher taxes and relinquish more control over their lives to experts who will "save" them. (The most radical environmentalists want the earth's population reduced to about 300 million people. Do all those nice, religious people know that?)
The rush to put draconian emissions-measures in place quickly has an obvious political motive: when the climate cycle again turns cool, environmentalists can claim credit for averting disaster. High taxes, artificially costly fuel, irreparable damage to our industrial base, drastically reduced living standards, and ruinously retarded development in primitive parts of the world will be cited as the sure prescription for climate-stabilization. We shall hear that the greenhouse theory was correct and humans were indeed warming the planet. Activists will ignore actual data showing that CO2 levels are still increasing as the climate cools. (Climate scientists like Dr. Tim Ball say this is already happening.) With the desired policies in place, the data won't matter any more. This is the great thing about politicized science: data are only an ornament.
It is hard for Americans to get aroused about these matters, having long felt secure in their political leaders' resistance to radical environmental actions that might injure them. Even liberal Bill Clinton would not ask the Senate to ratify the Koyoto Treaty, recognizing that its protocols would harm the national economy. Mr. Bush has similarly resisted, until recently. After Democrats won a new congressional majority, Mr. Bush signaled that he was ready to support "climate control" initiatives. (We already spend over $4 billion a year on climate research.)
If Democrats take the presidency and still hold the Congress in 2008, Americans could find that the stalking horse of radical environmentalism has become a ravening beast - poised to gobble up wealth, livelihoods, and comfortable lifestyles. The results will be a lot more serious than a few murals whitewashed away. If it happens, it will be because we were too ignorant to stop it.
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4 years ago
Geometry and Dnamics..
Geometry and Dnamics..
1. Introduction The term
1. Introduction The term “art of Leonardo da Vinci” refers first to his famous paintings, of which few are finished and well conserved, and to the sketches and drawings which prepared his paintings and documented his scientific studies. Secondly, his theoretical thoughts on art and aesthetic s have been collected after his death by Francesco Melzi and gave rise to the “Trattato della pittura” (codex Urbinatus 1270) 1 . On the basis of the theoretical positions found in Leonardo’s “trattato” and in his notebooks (cf. MacCurdy, 1977) I shall try to elaborate the semiotics of art explicit and implicit in the work of Leonardo da Vinci. Leonardo da Vinci was born in 1452 in Vinci near Florence. The big economical and political centers in Italy were Venice, Naples, Milan, Florence, and Rome. Leonardo made the first steps of his career in Florence where he worked under Verrocchio, became master in his workshop, and finally became an independent master in 1477. When in 1482 several famous painters were called to Rome in order to achieve paintings in the Sistine Chapel, Leonardo was not considered and asked Ludovico Sforza in Milan for employment. He stayed in Milan until 1499, at which point Milan was taken over by the French troupes. Leonardo left Milan via Mantua, Venice (where he stayed for a short period) and Bologna before returning to Florence. In 1506 Leonardo was invited to Milan by the French governor Charles d’ Amboise and worked there until 1513. He left Milan because of the pestilence and went to Rome where he was the guest of Guilano de’ Medici (1479-1516), who was the brother of Pope Leo X. Rome was in this period the center of Renaissance art, but Leonardo did not participate in the great works in the Vatican and left Rome after being invited by François I, king of France, together with his pupils Melzi and Salai. From 1516 until his death in 1519 Leonardo lived in the Castel Cloux near Amboise in France. 2. What is “Semiotics of Art” in the context of Leonardo’s work? 2.1 The semiotics of painting, music, poetry, and science 1 Many of his original texts illustrated by sketches and drawings have been edited since; cf. MacCurdy, 1977, Clayton 1996 and Codex Leicester, 2007. All citations from the "Trattato della pittura" in the following refer to the critical edition by Pedretti, 1995. GeometryandDynamicsLeonardonew.doc 2 VON 33
In his “Trattato della pittura” Leonardo relates the art of painting with poetry, music, and science as an art based on mathematics (mainly geometry). If Leonardo thinks that the painter is master of all types of art, i.e., that painting is not only a science but that it has aspects of poetry and music, he presupposes a common basis for all four of the following domains: painting, poetry, music, and science. This means that he refers to a universal symbolic activity of man. It is the universality of Leonardo which makes him a semiotician, and it is his life-long reflection on the principles and on the “science” of painting (“scienza della pittura”, second part of his treatise) that makes him not only a theoretician of art but also of sign-usage. In the movement of Renaissance artists from a cultural practice, learned in the workshop of painters, musicians, and poets, to a reflection on the universal principles underlying this practice and the consequent development of new practices going beyond the “maniera” of their predecessors, Leonardo establishes the stage not only for the rapid further development of painting and art, but also for the rapid evolution of science. Although Copernicus’s “Commentariolus” began to circulate only after 1515, Leonardo may stand for the new generation of intellectuals in the time of Copernicus and the “modern” civilization of art and science in the 16 th and 17 th century, which is the basis of contemporary science. In his treatise Leonardo states that the objective of painters is to represent mainly two things: man and his mind 2 . The nature of man becomes visible, and therefore, accessible to the eye in the different movements, and in the proportions of his body parts (cf. Leonardo da Vinci, 1977: “Parte Terza. De vari accidenti di membra”). In order to represent man and his mind the artist must first create a pictorial space, which is the foundation for the topic of the painting. The basic technique rediscovered and further developed in Renaissance time is called the “linear perspective”; i.e., the artist must be able to represent the third dimension with the means of a pictorial plane. Secondly s/he must consider light and shadow before placing objects in space. Finally, landscape, sky, objects, animals, and persons included in the painting (mostly individuals or groups of individuals) must be arranged in space relative to light and shadow. The central concern is therefore the composition of the topic and 2 Cf. Pedretti, 1995: §180 (p. 219): "Il bono pittore ha a dipingere due cose principali, cioè l'omo e il concetto della mente sua. Il primo è facile, il secondo difficile, perchè s'ha a figurare con gesti e movimenti della membra;". GeometryandDynamicsLeonardonew.doc 3 VON 33
The geometry of the market
The Geometry The Nucleus
geometry by paper folding - (13 mb pdf) - Arvind Gupta
AP Racing - Objet Geometries
Strings and geometry - ICTP
specifications geometry - Kona
Balanced Hermitian geometry on nilmanifolds
10-1 Solid Geometry 10-1 Solid Geometry
Slides - Institute for Gravitational Physics & Geometry
topographic projection in american descriptive geometry workbooks
Integral geometry on complex projective space - Australian National ...
Overview of Direct Accelerated Geometry Monte Carlo - 2012
Exploring Architectural Form in Perspective - Perspective Geometry
Geometry EOC Assessment Guide - Louisiana Department of ...
slides of the lectures - Coxeter Groups meet Convex Geometry ...
The Uses of Differential Geometry in Finance - Andrew Lesniewski
Geometry Assessments - Charles A. Dana Center
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Biology 12th Edition
Published by McGraw-Hill Education
ISBN 10: 0-07802-426-9
ISBN 13: 978-0-07802-426-9
Chapter 2 - Basic Chemistry - Assess - Page 34: 13
B. water holds its heat
Work Step by Step
The temperature of water increases and decreases less rapidly than a lot of other fluids. Since a good percentage of the human body is composed of water, this allows us to maintain our body temperature well.
Update this answer!
Update this answer
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Lord of the Flies chapters 7-8 SQ and vocab
Definition: having rich or profuse growth
Definition: relating to motherhood
Definition: thick underbrush providing cover
Definition: attitude scornful of the motives or virtues of others
Definition: dullness; flatness; lack of sharp edges
Definition: to criticize or reprimand
Definition: incapable of being affected
Definition: sacredness; godliness
How does Ralph react when a boar comes charging down the patch?
When a boar comes charging down the path, Ralph immediately throws a spear at it, hitting it in its snout. Although he did not nearly kill the boar, he is overcome with excitement and eager to retell the story. This brings out a new side to Ralph’s personality, as he becomes violent and excited about the concept of killing.
To what does Ralph’s demonstration of his hunting prowess lead?
Because of his demonstration of his hunting skill, Ralph gains respect from all the boys. It solidifies his position as chief and causes the littluns to fear him. Unfortunately, it also leads to a reenactment of what happened, with a boy named Robert used as the boar. However, the reenactment escalates, and Robert ends up injured and almost killed.
What did the boys see on the mountaintop?
On the mountaintop, the boys (Ralph, Jack, Roger) see the corpse of a parachutist, but believe that it is the beast that everyone fears.
Why is the action of the story increasingly taking place in the near darkness or in the deep night when only the moon and stars give a little light?
When the story began, it was bright and happy and it took place in sunshine during the day. As the intensity of the story increases, and the boys become more violent and savage, the action moves near to nighttime, when it is dark out. This affects the mood, making things seem more dark and mysterious.
How does Ralph’s waning confidence in himself show in his words and actions?
Ralph’s self-confidence begins to decrease when he realizes that he is not an effective leader and that many of the boys are starting to join Jack’s side. This in his words and actions. During his speech, Ralph continually loses track of what he is saying and needs to think harder than in the past. He also bites his nails, plays with his hair, and talks to himself.
Although he is not able to get the boys to vote Ralph out of office as chief, Jack manages to overthrow Ralph’s authority. He creates a tribe of his own and invites everyone to join him. Some go and some stay with Jack. However, when Jack catches a pig offers it along with other food to the boys, almost all who stayed loyal to Ralph switch to Jack’s side.
Jack suggests that in order to keep the beast happy, they should stay off the mountain and give the beast an offering of the sow’s head mounted on a stick and her guts.
Describe Simon’s strange encounter with the Lord of the Flies
Simon finds the head of the sow the hunters killed mounted on a stick in the clearing he had previously visited, left as an offering to the beast. He has a hallucination, seeing the pig’s head swarming with flies. The head speaks to Simon, as the “Lord of the Flies,” explains that he will never be able to escape from the beast, because it lives in all humans.
Who or what is the Lord of the Flies?
The “Lord of the Flies” is the concept of evil. It is represented by the sow’s head, mounted on a stick.
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Wegener, Alfred Lothar (1880–1930)
Alfred Wegener
Photograph credit: the Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
Alfred Wegener was a German meteorologist, explorer, and geologist. In his 1915 book Die Entstehung der Kontinente und Ozeane ("The Origin of Continents and Oceans") he set forth what became known as "Wegener's hypothesis," or theory of continental drift, whose developments were in succeeding decades to revolutionize our view of the planet we live on.
Wegener's ideas crystallized in 1914 as he was recuperating in a military hospital from an injury suffered as a German soldier during World War I. While bed-ridden, he had time to develop an idea that had intrigued him for years. Like others before him, Wegener had been struck by the remarkable fit of the coastlines of South America and Africa. But, unlike the others, to support his theory Wegener sought out many other lines of geologic and paleontologic evidence that these two continents were once joined. During his long convalescence, Wegener was able to fully develop his ideas into the theory of continental drift. See also plate tectonics.
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A mber… Greek name for amber was ἤλεκτρον ( elektron ), “formed by the sun” Around 600bc, the Greek philosopher and scientist Thales of Miletus discovered that rubbing amber with a wool cloth would cause it to mysteriously attract paper, grass or feathers. Electricity!.
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We learned shocking power (and something about forces of nature) from lightning…and fish!
Electric catfish (Malapteruruselectricus) 350V
Electric “eel” (Electrophorus electricus) 600V
Electric rays (~60 species) 40-50V
Elektron, the Greek word for amber…
William Gilbert (1600) is the first to recognize the difference between the magnetic attraction of magnetite, and the static charge attraction built up on the surface of amber after it is rubbed…
Ben Franklin
1752, lightning =static charge
1755, charge exists on the exterior of a charged object…the interior is unaffected (the cage effect)
George Johnstone Stoney
G. JohnstoneStoney in Aug. 1874, and again in Feb. 1881.
"And, finally, Nature presents us, in the phenomenon of electrolysis, with a single definite quantity of electricity which is independent of the particular bodies acted on. To make this clear I shall express `Faraday's Law' in the following terms, which, as I shall show, will give it precision, viz.:-- For each chemical bond which is ruptured within an electrolyte a certain quantity of electricity traverses the electrolyte which is the same in all cases. This definite quantity of electricity I shall call Er. If we make this our unit quantity of electricity, we shall probably have made a very important step in our study of molecular phenomena."
“In this paper an estimate was made of the actual amount of this most remarkable fundamental unit of electricity, for which I have since ventured to suggest the name electron. According to this determination the electron = a twentiethot (that is 10¯20) of the quantity of electricity which was at that time called the ampere…”
development of quantum theory
Development of quantum theory
John Dalton (1766-1844)
-1808Every element consists of indivisible particles called atoms
James Clerk Maxwell (1831-1879)
-1865Maxwell’s field equations –
The birth of field theory (from Faraday)
The electromagnetic theory of light-
Light propagates as waves
Johann Balmer (1825-1898)
-1885Discovers numerological relationship between frequency and prominent spectral lines of hydrogen:
Michael Faraday (1831), the electromagnetic field
n = integer
ν = frequency
c = speed of light
R = Rydberg constant
Wilhelm Conrad Roentgen (1845-1923)
-1895Demonstrates X-rays in experiments with passing electric current through low- pressure gas
First Nobel Prize in Physics!
J.J. Thompson (1856-1940)
-1897 Identifies “cathode rays” as negative particles = electrons
Albert A. Michelson, 1894
William Thomson (Lord Kelvin), 1900
John William Strutt, 3rd Baron Rayleigh – Rayleigh scattering, Rayleigh waves, the theory of sound (his son was Robert John Strutt, 4th Baron Rayleigh – electrons
and gases, radiation)
Lord Rayliegh (1842-1919) and
James Jeans (1877-1946)
-1900 Calculation of black body radiation
“Ultraviolet catastrophe”
Max Plank (1858-1947)
-1901 Introduces the quantum concept -
Absorption and emission of radiant
energy in discrete packets
– Nobel Lecture of Max Plank (1920)
E = hν
h = 6.6262 x 10-34 kg m2 / sec
Albert Einstein (1879-1955)
-1905 Photoelectric effect and the photon concept…
Special relativity too!
Ernest Rutherford (1871-1937)
-1911 An atom consists of a positively charged nucleus and negatively charged electrons orbiting the nucleus at constant speed
Niels Bohr (1885-1962)
-1913 Quantum model of hydrogen
(early quantum theory)
Predicts the Rydberg constant and the line spectra for gaseous hydrogen
Bohr’s Three Postulates:
1) There are certain orbits in which the electron is stable and does not radiate
The energy of an electron in an orbit can be calculated - that energy is directly proportional to the distance from the nucleus
Bohr simply forbids electrons from occupying just any orbit around the nucleus such that they can’t lose energy and spiral in…
2) When an electron falls from an outer orbit to an inner orbit, it loses energy
…expressed as a quantum of electromagnetic radiation
3) A relationship exists between the mass, velocity and distance from the nucleus of an electron and Planck’s quantum constant…
From these principles, Bohr realized he could calculate the energy corresponding to an orbit:
m = mass of electron
e = charge of electron
ħ = h / 2π
If an electron jumps from orbit n=2 to orbit n, the energy loss is:
energy is radiated, and expressing Plank’s relationship in terms of angular frequency (ω), rather than frequency (ν):
Bohr theoretically has expressed Balmer’s formula and could calculate the Rydberg constant knowing m, e, c, and ħ
Modern quantum theory:
Louis de Broglie (1892-1987)
-1924 wave theory of matter
ultimately led to the development of
wave mechanics
Wolfgang Pauli (1900-1958)
-1925 the exclusion principle
No two electrons can be in the same place at the same time
Electrons in an atom can be described by four quantum numbers
λ particle wavelength
h Planck’s constant
pparticle momentum
m rest mass
ν particle velocity
Predicted the neutrino!
Werner Heisenberg (1901-1976)
-1925 matrix mechanics
Observables are the sole source of change
-State vector does not change with time
Erwin Schrödinger (1887-1961)
-1926 wave mechanics
states are the sole source of change
Max Born (1882-1970)
-1926 Waves are probability waves
Paul Dirac (1902-1984)
-1925-28 Quantum field theory
Resolved particle-wave duality
Predicted antimatter
The relativistic quantum mechanical wave function (a relativistic generalization of the Schrodinger equation):
Bethe equation:
Hans Bethe (1906-2005)
-1930 Evaluates passage of charged particles through matter
From first Born approximation:
Bethe’s ionization equation – the probability of ionization of a given shell (nl)
Describes energy loss of charged particle with distance …
Development of concepts - SEM
Ernst Abbe (1840-1905)
-1878Geometric optics and the
resolving power of a microscope
What is resolution?
All lens images are diffraction patterns (circular slit diffraction)
An image point will be a disk, surrounded by diffraction rings representing diffraction maxima and minima
Airy Disk
Rayleigh Criterion: Central maximum produced by one object point must exceed the first diffraction minimum of the other object point…
fully resolved just resolved unresolved
At small angles…
Extreme rays from O’ to I differ by 1.22λ, so …
To A
Total path difference is then…
To B
The Abbe equation
Here, n is the refractive index
1) Visible light λ = 560 nm, for aperture angle of 0.9, and n = 1…
2) Electrons (remember de Broglie and the wave theory of matter) λ = 0.0054 nm…
• True resolution depends on
• Beam brightness
• Lens aberrations
• Scattering in specimen
Mass of an electron = 9.1091 X 10-31 kgSpeed of light = 299,790,000 meters/secondEnergy of an electron = 1.602 X 10-19 Newton meters/secondPlanck's Constant = 6.6256 X 10-34
Accelerating voltage physics calculator, University of Oklahoma electron microscopy laboratory
Louis de Broglie and the wave theory of matter allow the introduction of the basic concept of electron microscopy, but before that…
-1913Henry Moseley (1887-1915)
Following Bohr’s work, he demonstrates that the wavelengths of emitted X-rays correlates with atomic number
Moseley’s Law:
f= frequency, Z = atomic #
k1 and k2 are constants
-1914Max von Laue (1879-1960)shows that a beam of X-rays passing through a crystal produces a diffraction pattern.
-1914Karl Siegbahn (1886-1978) Discovered M-series of wavelengths in X-ray emission spectra, and developed methodology and instrumentation for detailed X-ray spectroscopy.
-1915WilliamBragg (1864-1942) and his son, W. Lawrence Bragg (1890-1971) pioneer the analysis of crystal structure using X-ray diffraction.
SEM and EPMA development
1926 – Hans Busch establishes geometrical electron optics theoretically
1927 – Hugo Stintzing develops the cathode-ray scanning microphotometer, and essentially develops the concept of the scanning electron microscope
1928 – Ernst Ruska experimentally demonstrates electromagnetic focusing.
1931 – Max Knoll and Ernst Ruska build the first transmission electron microscope (Berlin) (receives Nobel Prize…1986)
“conventional” TEM, not scanning
1931 – Johann and Cauchois develop sem-focusing spectrometers by bending multilayer structures.
1932 – Johansson develops the focusing spectrometer by bending a crystal to twice the radius if the focusing circle, then grinding to achieve full focus.
1938 - Manfred von Ardenne
Credited with developing the first scanning electron microscope
The first commercial electron microscope is introduced by Siemens
1942 – Vladimir Zworykin, James Hillier, and R.L.Snyder develop the first thick specimen SEM at RCA labs
Vladimir Zworykin
1943 – James Hillier develops the concept for electron probe microanalysis – the use of a focused electrons impinging on a specimen and their utility in chemical characterization.
1949-1951 Raimond Castaing develops the concept for electron-probe, X-ray microanalysis (using characteristic X-rays for chemical analysis), and builds the first electron microprobe in Paris
This becomes the basis for the first commercial instrument, introduced by Cameca in 1956
1965 – First commercial SEM is offered by Cambridge Instruments
(The first commercial TEM had been introduced by Philips Electron Optics in 1949)
Many commercial SEMs today:
JEOL (Japan Electron Optics Lab)
Carl Zeiss
Cambridge Instruments + Wild Leitz = Leica (1990)
Carl Zeiss + Leica = LEO (1995)
LEO integrated into Carl Zeiss (2004)
Carl Zeiss acquires ALIS (2006)
FEI and Philips Electron Optics merge 1997
FEI acquires Micrion 1999
Topcon / ISI
1960s brought expansion of electron microprobe technology and commercial availability:
Cambridge Instruments
Advanced Metals Research
Applied Research Laboratories
Elion Instruments
Materials Analysis Company
Only Cameca and JEOL offer dedicated electron microprobes today
SEM technology today:
Ultra-high resolution
(now to 0.4-0.5nm, Hitachi S-5500)
Cold field emission
Schottky emission
Variable pressure
SEM technology today:
Extreme high resolution
Sub nm image resolution for full voltage range
Analytical current capability
(FEI Magellan)
Energy filtered Schottky emission
Ti barrier
Sidewall spacer
Poly Si
W contact
Al line
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First-Signal System
First-Signal System
a system of conditioned-reflex connections that forms in the cerebral cortex in response to the action of internal or external stimuli on human and animal receptors. The first-signal system represents reality in the form of sensations and perceptions.
The term “first-signal system” was introduced in 1932 by I. P. Pavlov during his research into the physiological mechanism of speech. According to Pavlov, in animals reality is signaled mainly by stimuli that are perceived directly by sensory receptor cells and are processed in the cerebral hemispheres. “Other than written and heard words, this is all that we internalize to form impressions, sensations, and ideas from the surrounding natural and social environments. This is the first-signal system of reality, and we have it in common with animals” (I. P. Pavlov, Poln. sobr. soch., 2nd ed., vol. 3, book 2, 1951, pp. 335–36).
In the course of a person’s working and social life, the first-signal system is supplemented by a new and specifically human system of verbal signals—the second-signal system. Pavlov wrote that “words have formed the second-signal system of reality, which is specific to us and serves as the signal for the first signals” (ibid, p. 336). Both human signal systems differ qualitatively from each other, but they interact closely and harmoniously. (See HIGHER NERVOUS ACTIVITY.)
Pavlov, I. P. Poln. sobr. soch., 2nd ed., vol. 3, book 2. Moscow-Leningrad, 1951.
Orbeli, L. A. Izbr. trudy, vol. 3. Moscow-Leningrad, 1964.
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Meaning of B in English
Pronunciation: ' b ē
Function: noun
Inflected Form: plural b's or bs \ ' b ē z \
Usage: often cap
often attrib
before 12th century
1 a : the second letter of the English alphabet b : a graphic representation of this letter c : a speech counterpart of orthographic b
2 : the seventh tone of a C-major scale
3 : a graphic device for reproducing the letter b
4 : one designated b especially as the second in order or class
5 a : a grade rating a student's work as good but short of excellent b : one graded or rated with a B
6 : something shaped like the letter B
7 capitalized : the one of the four ABO blood groups characterized by the presence of antigens designated by the letter B and by the presence of antibodies against the antigens present in the A blood group
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1. 130-year-old whale
In May 2007, indigenous hunters killed a bowhead whale off the Alaskan coast. Embedded into the shoulder bone of the whale was an exploding harpoon that they were able to date to being used in 1890, meaning the whale survived the attack and lived a further 117 years with the harpoon under its skin. This allowed scientists to guess the age at around 130.
2. 405-year-old shellfish
In 2007 it was reported that one large Quahog was pulled from a depth of 80 meters and killed so researchers could count its rings. They were stunned when they determined the shellfish was 405-years-old, making it the oldest non-colonial animal ever discovered.
3. 4,900-year tree cut down by a lazy scientist
In 1964, geographer Donald R. Currey got permission from officials to take tree ring samples in Nevada’s Great Basin National Park. One of the species that grow in this high altitude area is the Bristlecone pine, which is famed for its age. Currey hoped that he could use its ring data to track glacier movements. For some reason, he decided not to use the tree borer, and just cut down the tree instead. When he got back to lab it was learned that he had killed the oldest tree ever discovered, estimated to be about 4,900 years old. Nicknamed Prometheus, the tree held the record until 2012 when an older tree was found – another bristlecone, which was 5,065 years old.
4. 327-Pound, 94-year-old dinosaur fish
On February 14, 2011, Kenny Williams landed a monster-sized Alligator gar near his home in Vicksburg, Mississippi. The dinosaur fish was so big he had to use nets to drag it onto his boat. Once it was weighed it smashed earlier records at 8.5 feet long and weighing in at 327 pounds. Such a large Alligator gar was determined to be about 94-years-old.
5. 100-year-old (at least) lobster
The biggest lobster ever (that we know of) was caught off Nova Scotia, Canada in 1977. It weighed in at 44 pounds, 6 ounces and was believed to be around a 100-years-old. The ancient lobster giant was sold to a restaurant, where it ended up on the menu.
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Archaeology and Environment
1 2 3 4 5 6 7 8
Prior to beginning construction of the current Indian River Inlet Bridge, the Delaware Department of Transportation (DelDOT) was required by state and federal law to conduct an archaeological study to determine if the site contained areas of historical or cultural significance. The study found no evidence of historical human habitation. This is most likely due to the harsh living conditions that would have been present at the site prior to the 20th century. However, archaeologists did find window glass, bricks, and stoneware indicative of possible ships or shipwrecks, as well as a variety of shells and stones that are typically found in a coastal environment.
The Indian River Inlet is a unique body of water which connects the Atlantic Ocean with the Indian River Bay. Research indicates that the location of the inlet naturally migrated up and down the coast until the early 20th century when it was secured in place by the Army Corps of Engineers. The natural movement of beach sand and stones due to erosion and tides presents a dynamic, constantly changing environment.
The growing popularity of Delaware's beach-resort towns in the first half of the 20th century coincided with a significant increase in personal automobile ownership. As more people sought the tranquil coastline and beaches, Delaware responded with the construction of the Ocean Highway (now Coastal Highway/State Route 1) between Rehoboth Beach and Bethany Beach. This roadway was completed in 1933. In order to complete the link, a bridge was built across the Indian River Inlet.
1 2 3 4 5 6 7 8
IRIB History Title Image
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Download a PDF to print or study offline.
Study Guide
Cite This Study Guide
How to Cite This Study Guide
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Course Hero. "Nicomachean Ethics Study Guide." Course Hero. 8 Jan. 2018. Web. 24 Sep. 2018. <>.
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Course Hero. (2018, January 8). Nicomachean Ethics Study Guide. In Course Hero. Retrieved September 24, 2018, from
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(Course Hero, 2018)
Course Hero. "Nicomachean Ethics Study Guide." January 8, 2018. Accessed September 24, 2018.
Course Hero, "Nicomachean Ethics Study Guide," January 8, 2018, accessed September 24, 2018,
Nicomachean Ethics | Book 8 | Summary
Section 1
Friendship is essential to the virtuous life. Even if someone had everything else they needed, they would not want to live without friends. People can share their prosperity with friends during good times, and friends can help guard their riches. In hard times, people take refuge with friends. Young and old people, who are especially vulnerable, need friends to help them. Moreover, people "in their prime" need friends to enrich their own capabilities.
Friendship extends to many units of society. Families provide natural friendships. "Members of the same species," particularly humans, share a natural kinship. On a political level, Aristotle thinks legislators of cities are more concerned with friendship than with justice. In fact, friendship is "the justice that is most just." Not only is friendship necessary, it is a virtuous quality; good people make good friends.
However, what kinds of people can be friends with one another? Do friends need to be similar, or can they be opposites? Moreover, how many types of friendship exist? Aristotle says he will be skipping the questions about friendship rooted in natural science to discuss the topic in relation to human nature.
Section 2
Before Aristotle examines friendship, he needs to discuss love. What does it mean when someone or something is "lovable"? People love what's "good or pleasant or useful." People can love universally good things, which are "lovable without qualification," and people can love goods that are more specific, that are good only for themselves.
How do friends experience love? Someone can love an inanimate object, like wine, but this is not friendship. Wine cannot love anyone back, and no one wishes "good things to wine." Similarly, if someone wishes another person well but their wish is not returned, they feel only goodwill, not friendship. Friendship is "reciprocated goodwill." Someone wishes good things to a friend for the friend's own sake, and receives good wishes in return. Friends must also be aware of the mutual goodwill.
Section 3
On the basis of the three types of love defined in the previous section—love for the good, the pleasant, and the useful—Aristotle defines three types of friendship.
The first type is friendship for utility. Friends for utility focus on what they can gain from the other person. Since people's needs change, they will dissolve a friendship for utility once their need is met.
The second type is friendship for pleasure. Friends for pleasure have fun being around the other person but do not really appreciate their character. Like a friendship for utility, a friendship for pleasure lasts only as long as the benefit of pleasure lasts. Older people tend to make friends for utility, since older people tend to seek advantage more than pleasure. Young people, who live according to their feelings, make friends for pleasure and change friendships quickly.
The third type of friendship is complete or virtuous friendship. These friends wish good to each other for the other person's own sake, not for any kind of gain. These are lifelong friendships, which last as long as both people remain good. Virtuous friends are both "good without qualification" and good for each other. These relationships are rare and take time to develop, but they are the most rewarding.
Section 4
How do the three types of friendship compare? There are some overlapping traits. Virtuous friends are also pleasant and useful to each other. Moreover, the two incomplete friendships—pleasure and utility—last the longest when the two parties each get the same benefit from the same source. An erotic relationship, for instance, may dissolve easily if the participants find different sources of pleasure in each other—if one is courting and one is being courted. However, friends for pleasure who truly come to enjoy each other's personalities may remain friends for a longer time.
Good or "decent" people can have incomplete friendships with bad or "base" people. In addition, base people can have incomplete friendships. Only good people can have truly virtuous friendships with trust and without slander. Trust requires belief that a friend "would never do injustice" and evidence of the friend's reliability over time.
Incomplete friendship types can still be useful. Diplomatic alliances between cities, for instance, can be considered friendships for utility. Nevertheless, incomplete friendships rely on only the similarities between the two parties, not on a friend's goodness.
Section 5
Friendships, like virtue, can be expressed through a "state of character" or through "activity." Although friends frequently participate in activities together, they can often remain friends during a short absence. The distance changes their activity but not the character of their friendship. Since a pleasant character is important to any kind of friendship, "older people and sour people" do not usually have friends.
People who are friendly to each other but do not spend much time together have "goodwill rather than friendship." The happiest people will want to increase their happiness by spending time with true friends.
The truest kind of friendship is "the friendship of good people." These relationships are choice worthy in their own right or "without qualification." They are pleasant for each individual too.
Aristotle classifies friendship as a state rather than a feeling. The "reciprocal loving" needed for friendship "requires decision, and decision comes from a state" not from an emotion. True friends wish good to each other regardless of their personal feelings or emotions. True or virtuous friends benefit themselves as much as they benefit each other, and the relationship is based on "equality."
Section 6
Aristotle goes more in depth into various kinds of friendships and the activities that accompany them.
Although older people and "sour people" are solitary and have few friends, they may extend goodwill to others in times of need. People can have only a few true friends at once, since complete friendship requires "excess" of mutual regard between people who are also both good. It is hard to find and get to know truly good people, and it takes time to put in true friendship's effort.
Incomplete friendships, on the other hand, are easier to find and take less time to develop. Of the two incomplete types of friendships, the friendship for pleasure seems more complete than the friendship based on utility. It is based in enjoyment—an essential component of a good life—and shows a generosity lacking in older or "mercenary" people who make friendships for utility. A powerful person will be able to maintain a group of useful friends and a group of pleasant friends, since it is rare to find someone who has both qualities. The excellent person does have the ability to be "both pleasant and useful," but they are unlikely to befriend a powerful person, since they seek a friend who is "superior in virtue" as well.
Incomplete friendships, like virtuous friendships, involve equality in exchange. However, these relationships, unlike virtuous friendships, change quickly and do not tend to last.
Section 7
Friendships can arise between people with different levels of power. A father's relationship to a son, a man's relationship to a woman, and an older person's relationship to a younger person all "rest on superiority." For this friendship dynamic to work, the love must be proportional to each person's worth. The "better" and "more beneficial" person must be loved more. This proportional feeling will achieve a type of equality.
Equality in justice is distinct from equality in friendship, since worth is more important to justice, and "quantity" or proportionate equality is more important to friendship. If two friends become separated by a gap in "virtue, vice, [or] wealth," their friendship will dissolve. Ordinary people do not befriend kings, and "worthless" people do not befriend wise people.
However, if friends wish each other the greatest good, shouldn't they wish for their friend to "be a god," since divinity is the highest good humans can aspire to? If one friend achieves a divine level of goodness, they will no longer have any human needs, including friendship. Even true friends will not desire this change in status. They will wish each other the greatest good as a human being.
Section 8
Unlike honor and flattery, friendship "[consists] more in loving than being loved." Average people or "the many" want to be loved and honored more than they want to love and honor others. However, they do not want honor for its own sake—they hope honor will bring them good treatment from powerful people, or help them "confirm their own view of themselves." Love, though, is something people desire for its own sake. Friendship, like the love it brings, is "choice worthy in its own right."
Aristotle compares the love of true friendship to a mother's love for a child. A mother will love a child regardless of whether the child loves her as much as she loves the child.
Friends who love and praise each other according to the other person's worth have the most enduring relationships. This explains "how unequals as well as equals can be friends"—appreciation based on worth is a way for the uneven relationship to be "equalized." Aristotle emphasizes the importance of "equality and similarity" in friendship, particularly similar levels of virtue. Virtuous people strengthen each other and discourage each other from base actions. Their friendships are based on equal exchange, unlike a friendship for utility, which may involve two people finding what each one lacks, such as a poor person befriending a rich person. However, two "contrary" or opposite people cannot be friends in their own right. They are only seeking whatever they lack themselves.
Section 9
Community dynamics are also based in friendship. Each community, small or large, requires both friendship and justice. Nevertheless, since community members do not have as much in common as two close friends might, the appropriate type of justice will differ depending on personal relationships within the group. Justice between parents and children, for instance, is different from justice between siblings. Moreover, people treat their close friends differently than they treat other community members. It is considered worse to treat a friend or family member unjustly than it is to treat a stranger the same way.
Each small group—family members, groups of friends—is part of the larger political community. Smaller sections of a city, such as soldiers, neighborhood or deme residents, and religious societies, seek "partial advantage" or what is good for their group; legislators seek the "common advantage" for all. The political community is the most important, since it helps the most people. Civic festivals sponsored by the government, for example, give everyone a chance to relax and honor the gods.
Section 10
After Aristotle discusses the importance of political community to human relationships, he defines the three types of political systems, and a "deviation" or corruption of each one.
Kingship, which Aristotle regards as the best system, can be corrupted by tyranny. A king considers the good of his subjects, while a tyrant considers only his own good.
Aristocracy, the second-best system, is the rule of the most decent people. Its corrupt version is oligarchy, the rule of the most vicious people.
Timocracy, which Aristotle sees as the weakest system, is majority rule in which everyone with an equal amount of property has an equal voice. Its corruption is democracy, or majority rule without regard for class. Democracy is still similar to a "[genuine] political system" and is the "least vicious" corruption.
Household power structures resemble governments in miniature. A father's rule over his house is similar to kingship. In fact, kingship is designed to be "paternal rule." A father can also be a tyrant if he "treats his sons as slaves."
A union between a man and a woman resembles an aristocracy, since the man, considered superior, "commits to the woman what is fitting for her." This union can become an oligarchy if the man grows too powerful. A community of siblings close in age resembles a timocracy, since all members are equal. In addition, "dwellings without a master" have democratic rule.
Section 11
Different friendships result from each political system. A king is a beneficial, superior friend to his subjects, and a father is a friend to his children in a similar way. A father gives children greater benefits, since he brings them into the world. In both kingships and parent/child relationships, justice is based on individual worth.
Men and women have friendships in which each one receives goods according to their worth. Siblings have friendships based on equality, similar to the friendships found in a timocracy.
Corrupt political systems or deviations do not have justice, so these systems do not tend to encourage friendships. "Ruler and ruled" do not have enough in common to be friends. Where inequality is too great, like between a tyrant and his subjects or between a master and a slave, friendship and justice are impossible. Nevertheless, every human being does have "some relation of justice" with every other human being in a community, and this broad relationship slightly resembles friendship.
Section 12
The family unit has special types of friendships, all stemming from "paternal friendship" or a father's fondness for his children as a part of himself. A child's bond to a parent relies on need, pleasure, and utility. A child's friendship with a parent is "friendship toward what is good and superior." Siblings and cousins close in age have more companion-like friendships. Siblings have the similarity required for friendship because they are from the same blood, nurtured and educated together, and able to trust each other over time.
Humans form couples more easily than they form larger communities, and the family bond extends beyond childbearing responsibilities to mutual benefits. For instance, a husband and wife can perform different functions and fulfill different family needs, contributing both pleasure and utility. Family members can even cultivate virtuous friendships if both individuals are virtuous themselves.
Knowing how to treat friends and family members with justice is essential to living a just life, Aristotle explains. However, each relationship requires an appropriate kind of justice.
Section 13
What about disagreements between equal friends? The best way to handle these disagreements will depend on the type of friendship. Friends for virtue want the best for each other, whether these friendships have a foundation of equality or superiority. In each case, the friends will aim to benefit the other person in all their actions. Friends for pleasure have simple expectations and spend time with one another only if they enjoy it. So virtuous friends and friends for pleasure are not likely to fight. Friends for utility are most likely to get into arguments, since they expect benefits from the friendship. Arguments arise when one person does not get what they feel they are owed.
To explain how disagreements in these friendships can arise, Aristotle mentions two types of justice: "one unwritten, and one governed by rules of law." Similarly, some friendships for utility rely on an unspoken understanding of the other person's character, others on previously established rules or "explicit conditions." When the terms of the friendship change, then accusations begin. For instance, a friendship for utility based on rules may involve a debt one person owes to the other. The lender can require immediate repayment or agree to postpone the debt, trusting the other person to pay. In a friendship for utility based on character, a lender may give his friend money but expect to be repaid with interest, although he will not make this expectation clear.
Aristotle says accusations happen because most people want to do the right thing, but they will do what benefits them instead. If the other person is a willing party to the friendship, the right thing to do is "make a return worthy of what we have received." Someone who didn't expect to have to repay a friend's loan, for instance, should act as if they "received a good turn on explicit conditions" whether they did or not. Anyone who owes money should repay if they can. Nevertheless, it is best to consider the terms and conditions of a favor at the beginning.
Should the return be measured by the recipient's benefit or by the worth of the benefactor's gift? A recipient might think a financial gift was "a small matter" for a rich benefactor, while the benefactor thinks they gave as much as they could. In these cases, Aristotle thinks the return should be measured by the recipient's benefit, since the recipient was the one who received a gift—and because of the equal terms of the friendship, the benefactor expected "an equal return."
In a virtuous friendship, however, the measure should be the benefactor's decision. This decision is a sign of their "virtue and character" and should be respected.
Section 14
Disagreements between friends of unequal power usually result in the dissolution of the friendship. A wealthier person may consider a gift to be "a public service" rather than a friendship, since the poorer friend contributes nothing in return. Meanwhile the poorer person thinks a good friend would gladly share his wealth. They are both right—they should each get what they need in the correct proportion. The richer person should get more honor, and the poorer person more profit.
This principle also applies in political communities. A politician receives honor for holding office, so he should not accept monetary gifts. Friends of unequal power, like equal friends, should return gifts appropriately by giving honor in exchange for a gift of money or virtue. Friendship, unlike political justice, "seeks what is possible, not what accords with worth." Some gifts cannot be fully repaid, like what children owe their parents or what humans owe the gods, so the inferior party should do the best they can. Moreover, the more powerful party can change the agreement's terms. A creditor can discharge a debt, for example, and a father can disown a son, although he is not likely to do so unless the son is "far gone in vice." However, a debtor cannot discharge his own debt, and a son cannot disown a father.
Aristotle sees friendship as part of any livable human life. He defines it broadly. A lover or a family member can be a friend. The questions he raises in Book 8 apply to a wide range of human interactions, from daily civility in social settings to family loyalty and political participation. Do people gravitate toward people like themselves, or do they search for someone who has qualities they lack? Can "base" or "vicious" people be saved by strong friendships? What happens when friends have different expectations for the relationship?
The lovable, similar to the good, can be either "lovable without qualification" (what the excellent person loves) or lovable to some people and not others. By love, Aristotle means philia or friendship: the affection, devotion, and concern of "reciprocated goodwill." This is not always love in the romantic sense, but it can be part of romance.
He acknowledges that each type of friendship has its place, although some can enrich lives more than others can. The incomplete friendship types, based on utility or pleasure, have things in common with the complete and virtuous friendship. All friends should please each other and help each other in times of need. Nevertheless, the devotion of virtuous friendships depends on loyalty, not circumstance. Virtuous friends stay together even if one person is not useful or fun to be around at the time. Incomplete friends may wish the other person well, but their primary interest is in what the friend can offer them.
Like cultivating virtue, establishing virtuous friendships takes work, time, and effort, and it is not possible for just anyone. People who want truly complete friendships should improve their own characters first. It also requires, like virtue, the right state, decision, and activity. By "living together" Aristotle means participating together in life's activities, not living in the same house. True friends deliberately invest time in each other and make a decision to love the other person. A good person can still have friends for utility and pleasure, but these friends will not be their focus.
Sections 7 through 13 take the basic discussion of friendship and move it into the realm of political life. Like politics, friendship needs to perform the delicate task of balancing equality with the power and status differentials in a community. Some provisions in Section 7 ensure the division between unequal friends will not be too great. The more beneficial party is repaid with more love. Friendships do not bridge huge gulfs in economic status or mindset. However, in the rare cases when they do, these relationships still are not as stable as friendships between equals.
In Section 8 Aristotle examines the currencies of friendship, which are love and honor. Although a flatterer can get insincere honor, it is hard to find insincere love. In complete friendship, Aristotle implies, equality will not even come up as a concern. Genuine love, offered according to worth, can be an equalizing force.
In larger communities, love translates to justice, or selfless actions for the common good. These social groups can come in diverse forms, like families, clubs, professional associations, religious societies, neighborhoods (a deme is a neighborhood or village), and most importantly, the city or polis. Aristotle relates friendship to the devotion people have for their fellow citizens and ultimately their governments.
Which governing systems will be best for the city? Aristotle compares each type of government to a household relationship, since even readers without much political experience are more likely to know the dynamics of a family. In his view, families mirror political systems in their organization, expectations, and uses and abuses of power. A good father, like a good king, will rule benevolently and selflessly.
In ancient Greece, the father of the family had a great deal of power over his spouse and children, so the "kingship" analogy would make sense to the audience attending Aristotle's lectures at the Lyceum. Men were seen as superior to women by definition, and slaves inferior to free men. Elsewhere in the text, he acknowledges that slaves have souls and that they have standing in the eyes of the law, but he questions the extent of their humanity. Aristotle's reservations about democracy may stem from his belief that some people are more suited to rule than others. Freedom, he thinks, can easily be abused. Similarly, deviant systems affect the welfare of their citizens, leading to a decline in trust and friendship.
His description of the family unit in Section 12 shows how he views families as models for cities. Like a father, a good king should love his subjects sacrificially and selflessly, and see their welfare as identical to his own. Parents are children's earliest model for human relations to the gods, one of the most sacred relationships Aristotle acknowledges. Spouses model ideal political relations by assigning goods in proportion to worth.
In Sections 13 and 14, Aristotle considers the inevitable difficulties in incomplete friendships, difficulties he thinks are rooted in justice. Political justice, like friendship, requires humans to follow certain guidelines in their behavior. For Aristotle, political relationships were a natural extension of other human interactions such as family relations and friendships, probably because Athens was governed by a small, tightly connected group of men. Without the central ingredient of trust, friendships are liable to fall apart. Most of the examples Aristotle uses in these sections have to do with money. He knows money is a contentious issue, often intersecting with need, and people may find it difficult to display virtuous character when money's involved.
Aristotle traces disputes in friendship to unmet, unknown, or undisclosed expectations. A gift turns out to be a loan, or a wealthy friend does not donate enough to a struggling friend. Many relationships have unspoken expectations. Nevertheless, virtuous friends have more reasonable expectations of each other and more skill at assessing their friends' ability to meet them. Virtuous people are also more likely to follow through with a desire for right action. They may forgive a debt or do a favor without expecting one in return. Most people will wish to act selflessly until human need and greed comes into play. Then they will base their decision on their own pleasure or benefit.
Even friends with unequal statuses can make a fair return for benefits. As in distributive justice, Aristotle thinks the key is proportion rather than equality. He also applies the principles of justice in exchange. Honor can be exchanged for profit; although the currencies are different, each member of the community gives what they can. Moreover, in special circumstances, like disagreements between fathers and sons, or cases in which a friend cannot possibly pay back a debt, people should let decency, prudence, and wisdom guide their actions. Although disowning sons was a practice allowed in Athenian law, Aristotle holds the father/child relationship sacred and feels disowning should be a last resort.
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Photo courtesy of the concord museum
Photo courtesy of the concord museum
There were widely diverse influences on Ralph Waldo Emerson's life and thought: his own experience, his classical and theological education, the people he knew, and those whose lives he studied.
A voracious reader of biography, philosophy, history, literature and poetry, Emerson's "philosophy" took shape in a world rich with resources of his own gathering: of books, travel, nature, and a broad acquaintance with the folk of his town and the great thinkers and actors of his time.
A representative list of notable influences:
Mary Moody Emerson
A Genius always new, subtle, frolicsome, judicial, unpredictable…
Ralph Waldo Emerson’s Aunt Mary Moody Emerson exerted a powerful influence on him from his days as a youth. She was self-educated, widely read and described by her nephew as “the best writer in Massachusetts.” She exhorted her nephews to “always do what you are afraid to do,” and by her insistence set standards for their intellectual growth. Emerson copied out some of her letters into four substantial notebooks later in his life and constantly referred back to her maxims and her influence.
Literary Influences
Some books leave us free and some books make us free.
In Concord, Emerson was surrounded by creative thinkers, writers, social activists and leaders. His own library, and the wide variety of books which he read and reread, provided rich sustenance for his ever-curious mind.
Emerson returned to Plato continuously, to better understand him, and to affirm his own conviction that “ideas are real because they are the forms and laws that underlie, precede and explain appearances.” (From Robert Richardson’s Mind on Fire).
Sampson Reed’s Observations on the Growth of the Mind illuminated Emerson's understanding of Swedenborg, and of the concept that God is in everything.
Samuel Coleridge's Aids to Reflection steered Emerson to merge thoughts and ideas from Plato and other writers of the past with more recent authors and poets, helping him to understand the power of self.
Emanuel Swedenborg, an 18th century scientist, founded Swedenborgianism and wrote about the relationship among the natural, scientific and divine worlds. In Emerson’s 1833 lecture The Uses of Natural History, he comments, “The whole of nature is a metaphor or image of the human mind.” Swedenborg’s teachings on the connection between the mind and nature greatly influenced Emerson.
Victor Cousin, a French philosopher who sparked in Emerson a life-long interest in Asian philosophy.
Johann Wolfgang von Goethe (1749-1832), an eminent German writer, whose views on science and nature inspired Emerson, and played into his first book, Nature. Goethe had written “Every natural form to the smallest, a leaf, a sunbeam, a moment of time, a drop, is related to the whole, and partakes of the beauty of the whole.” Emerson wrote “Goethe teaches courage.”
Thomas Carlyle, a Scottish writer who became a cherished friend and correspondent of Emerson, after they met in Scotland. Carlyle’s State of German Literature spurred the move by Emerson and others to Transcendentalism.
William Wordsworth, the English poet, whose work Emerson read extensively and whom Emerson met in England. Emerson, also a poet, is said to have known much of Wordsworth’s poetry by heart.
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Bersiap Period
In late September 1945 the Dutch and Indo-Europeans in Java were confronted with a wave of violence. The first weeks of September had been largely uneventful, but with the arrival of the first RAPWI teams the tensions began to mount, leading to an increase in incidents. By the end of September, young Indonesian guerrillas called pemudas had begun to take over government buildings and utilities in cities such as Yogyakarta, Solo, Malang, Bandung, Surabaya and Batavia. At the same time, Indonesian nationalists declared a general food boycott against the Europeans, and they cut off supplies of water and electricity to the internment camps where most of them were living. The Bersiap period began in earnest at the end of the month. The Indonesian verb ‘bersiap' means ‘get ready' or ‘be prepared', and it became the battle cry for the pemudas during the Indonesian Revolution. During the months of October, November and December 1945 the main cities on Java were the scene of continuous kidnappings, disappearances, shootings, thefts and murders. The main victims of the violence were the Indo-European, Chinese and Moluccan families living outside of the camps, as they were unarmed and scattered, and were therefore easy targets. The Bersiap reached its climax in the last weeks of October and the month of November, when British troops became entangled in combat with Indonesian forces in Central Java and in Surabaya. By the end of December British forces were able to restore order in Batavia, but conditions in Bandung remained unstable until March 1946. Estimates of the number of civilian casualties during the Bersiap vary widely: in the last three months of 1945 somewhere between 3,500 and 20,000 people are thought to have been killed in Java.
H.Th. Bussemaker, Bersiap! Opstand in het paradijs. De Bersiap-periode op Java en Sumatra 1945-1946 (Zutphen, 2005);
Mary C. van Delden, De republikeinse kampen in Nederlands-Indië oktober 1945-mei 1947. Orde in de chaos? (Kockengen, 2007)
Elly Touwen-Bouwsma en Petra Groen, Tussen Banzai en Bersiap. De afwikkeling van de Tweede Wereldoorlog in Nederlands-Indië (Den Haag, 1996).
Information a.o. in:
Access Number 2.22.21, 164, 165, 166, 167, 172, 174, 175, 1015,
1016, 1018 and 1021
Access Number 2.10.14, 2988, 3021, 3044, 3584 and 5518
Access Number 2.10.62, 2269
Access Number 2.13.72, 18 and 339
Available in the reading room:
Access Number 2.10.62, 999, 1000 and 1001 (Rapporten van de Afdeling Intelligence en Loyaliteitsonderzoek van de AMACAB te Batavia, 1945. Information about Java)
See also:
- Indian Divisions
- Diplomatic and Military Relations with Great Britain
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Different writing
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WritingFix - official Site
Deductive thinking is also called syllogistic thinking. See induction, logic, and logical fallacies, and the class's syllogism handouts. Deductum carmen (Latin, "drawn-out song ovid's term in Eclogue.3-5 for the type of poem he will create in his own poetry, in contrast with the older epic. He claims that a "modern" (i.e., imperial) poet of his day should not be writing epics, but instead should follow the example of Callimachus, in which the poem's narrative structure is drawn out in a manner akin to the way a thread is drawn out. This method contrasts with the epic, in which a single narrative focusing on kings and conquerors broadly dominates the entire poem. Deep structure : In noam Chomsky's transformational grammar, the biological "hardwiring" in the brain that gives children the capacity to use language, as opposed to the surface structure,. E., the incidentals of the language children actually learn.
Writing, elementary and Middle School, writing
Frequently, the dedication is to a wallpaper spouse, friend, loved one, child, mentor, or individual who inspired the work. Several of the Inklings dedicated specific fictional works to each other (or in the case. Lewis, to children of fellow Inklings). Among scholars, one of the most significant types of dedications is a festschrift. A festschrift is a collection of essays or studies in book form, dedicated to a former teacher or professor in his or her advanced age. The individual scholarly writings come from his or her students, who typically collaborate to organize the work and contact the publisher, and they present the collection to the teacher upon its publication. Deduction : The process of logic in which a thinker takes a rule for a large, general elite category and assumes that specific individual examples fitting within that general category obey the same rule. For instance, a general rule might be that "Objects made of iron rust." When the logician then encounters a shovel made of iron, he can assume deductively that the shovel made of iron will also rust just as other iron objects. This process is the opposite of induction. Induction fashions a large, general rule from a specific example. Deduction determines the truth about specific examples using a large general rule.
Click here for an example from Dagulf's Psalter in order to view one. Inhabited initial and historiated initial. Decorum lined : The requirement that individual characters, the characters' actions, and the style of speech should be matched to each other and to the genre in which they appear. This idea was of central importance to writers and literary critics from the time of the renaissance up through the eighteenth century. Lowly characters, low actions, and low style, for instance, were thought necessary for satire. Epic literature, on the other hand, called for characters of high estate, engaging in great actions, and speaking using elevated, poetic diction. Dedication : A short bit of text conventionally appearing before the start of a novel or poem in which the author or poet addresses some individual, invoking his or her gratitude or thanks to that individual.
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Hamlet review movie - empire
It would be more accurate to assert that deconstructionists deny the absolute value of literature, and assert that all literature is ultimately incapable of offering a constructed meaning external to the "prison-house of language which always embodies oppositional ideas within itself. Deconstruction is symptomatic in many ways of postmodernism. In the more radical fringes of postmodernism, postmodern artists, dramatists, poets, and writers seek to emphasize the conventions of story-telling (rather than hide these conventions behind verisimilitude ) and break away from conventions like realism, cause-and-effect, and traditional plot in narratives. Such a text might be called " deconstructed " in a loose sense. Decorated initial : In medieval manuscripts, this term refers to an introductory letter of a text division, embellished with some type of abstract design,. E., a design not necessarily containing a picture (which would make it an inhabited initial ) and not necessarily containing a scene from the story (which would make it an historiated initial ). Unlike the latter two types, the adornment in a decorated initial has no overt connection to the material discussed or narrated in the book's contents.
Autobiography of a, yogi by paramhansa yogananda overDrive
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Southwest Physician Associates - news and Current events
In particular, Théophile gautier, Charles baudelaire, oscar Wilde, and Audrey beardsley are representative writers and poets in this movement. Declension : see discussion under declined language or click here for example cases. Declined language : Also called a synthetic language, or an inflected language, a declined language is one in which word order is not as important in making meaning as the use of inflections or declensions -special endings stuck on the end of words-to indicate the. These endings are called declensions, a term that comes from the handwritten grammar charts used by medieval monks who create a series of angled or declined lines in specified patterns, and on these lines the students would write the correct word-ending as part of grammar. Click here for further information. Deconstructed : see discussion under deconstruction. Deconstruction : An interpretive movement in literary letter theory that reached its apex in the 1970s.
Deconstruction rejects absolute interpretations, stressing ambiguities and contradictions in literature. Deconstruction grew out of the linguistic principles of de saussure who noted that many Indo-european languages create meaning by binary opposites. Verbal oppositions such as good/evil, light/dark, male/female, rise/fall, up/down, and high/low show a human tendency common transculturally to create vocabulary as pairs of opposites, with one of the two words arbitrarily given positive connotations and the other word arbitrarily given negative connotations. Deconstructionists carry this principle one step further by asserting that this tendency is endemic to all words, and hence all literature. For instance, they might try to complicate literary interpretations by revealing that "heroes" and "villains" often have overlapping traits, or else they have traits that only exist because of the presence of the other. Hence these concepts are unreliable in themselves as a basis for talking about literature in any meaningful way. Oftentimes, detractors of deconstruction argue that deconstructionists deny the value of literature, or assert that all literature is ultimately meaningless.
Contrast with the "young man" sonnets earlier in the collection. Darra arlo (on, "Song of Dorrud In the last chapters of Njal's Saga, a minor character named Dorrud sees a group of twelve mysterious women (probably intended to be the valkyries). The women enter into a room and sing as they weave a loom composed of human heads, intestines, swords, and arrows-an idea often associated with the norns (the Old Norse equivalent of the Greek fates or Roman Parcae ). Scholars traditionally refer to this section of Njal's Saga and the women's song as the darra arlo. Dative : see discussion here. Dawn song (also called an aubade a genre of poetry common to europe in which the poem is about the dawn or coming of dawn, or it is a piece of music meant to be sung or played outdoors at dawn.
Examples include Browning's "The year's at the spring / And day's at the morn" from Pippa passes or Shakespeare's "Hark! The lark." Some poems, such as John Donne's "Busy old sun" share traits with the dawn song, and Chaucer's Troilus and Criseyde also contains an example inside its larger narrative. Dead language : In linguistics, a dead language is one that does not change any more over time-it is "frozen" historically because it is no longer used in everyday discourse, but is instead learned only for ritual use, scholarly study, or the preservation. Classical Latin and Sanskrit are two examples of dead languages. This situation contrasts with a living language, in which old words die out, new ones are added, and existing words change their meaning continually over time from one generation to the next,. Baugh puts it (2). Decadence, the : A literary movement in late nineteenth-Century England, France, germany, and Spain associated with dark or "amoral" symbolism, focusing on the theme of artifice as opposed to naturalism.
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At this point, Alfred made a treaty with the danes so that England was divided. The northeastern section between the rivers Thames and tees was officially declared to be danish territory and later become known as the danelaw (where the inhabitants followed Danish law from 890 onward). The influence of this period of viking settlement is still visible in the north of England and the east Midlands, especially in toponyms or place-names. Towns with name-endings such as -by or -thorp are all places named by the viking settlers. Dans macabre (French, "morbid dance a gruesome motif or trend that spread through late medieval Europe's visual art, architecture, sculpture, and poetry in the wake of the Black Plague ( CE) and which remained common in woodcuts, gravemarkers, and cenotaphs through the renaissance two hundred. Visually, it took the form of imagery involving bones, skeletons, graves, and similar death-imagery, most famously in images of living revelers intermixed with animated skeletons carousing, eating, drinking, and dancing. Functionally, the art was a memento mori, a reminder of death's inevitability in the face of each individual's mortality. In terms of literature, we find traces of the dans macabre motif appearing in tombstone epitaphs such as " Such as i am, so shalt Thou be or poetic verse such as " Golden lads and girls all must, / As chimney-sweeps, come to dust.". This contrasts with the traditional Petrarchan conceits of a fair-haired and fair-skinned guaranteed lover who is coldly aloof to the male speaker's wooing.
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Danelaw (Anglo-saxon, dena lagu the region of northeast England up to the southern part of Scotland that was conquered and inhabited by viking invaders. In 871 ce, a wessex army under King Aethelred (the west Saxon king) and his brother Alfred confronted the danish vikings at the battle of Ashdown (in modern Berkshire). Unfortunately, after a series of losses, wessex began paying annual Danegeld (tribute) to the vikings. Aethelred died soon after, and viking settlers swarmed into the northern parts of England while their raiders occupied London. The vikings continued their expansion until 878. That year, king Alfred the Great rallied men from Somerset and Wiltshire writers and decisively defeated the danish vikings. The danes were too numerous to dislodge from their holdings, but it was clear that they would not be able to expand their territory while Alfred lived. King Alfred freed London from Danish occupation in 886.
that naturally constitute dactyls include strawberry, carefully, changeable, merrily, mannequin, tenderly, prominent, buffalo, glycerin, notable, scorpion, tedious, horrible, and parable. Verses written in feet that follow this pattern are said to be in dactylic meter. For further discussion, see meter, or click here for a pdf handout contrasting dactyls and other types of feet. Dagger : Another term for the symbol obelisk. Danegeld : The practice of paying extortion money to vikings to make them go away, often associated in particular with the Anglo-saxon king "Aethelred Unraed." His nickname means "Aethelred the Unready or more accurately translated, "Aethelred the Uncounciled." At various points in history, british kings. This failed policy of Danegeld ultimately led to large portions of northern England being settled by the vikings in the area known as the danelaw, which in turn played a key part in the evolution of the English language through the incorporation of Scandinavian loan-words. Words like skiff, ship, and shirt, for instance, are all loan-words borrowed from the vikings. Nb : Danegeld should not be confused with wergild.
Also, if you have a comment about a particular piece of work on this website, please go to the page where that work is salon displayed and post a comment. Email address, type of feedback, please selectSuggestionProblem / BugReport abuseOther, my feedback relates. Please selectA specific pageA part of the websiteThe entire site. Page url, your Comments. Literary terms and Definitions: d, this page is under perpetual construction! It was last updated April 24, 2018. This list is meant to assist, not intimidate. Use it as a touchstone for important concepts and vocabulary that we will cover during the term. Vocabulary terms are listed alphabetically.
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Maximize your storage and your style with study furniture from PBteen. It almost feels like a lot of The, girl on the, train 's potential was left on the cutting room floor, taken out for brevity or simplicity.
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6. Ielts writing correction and feedback on your mistakes from an examiner. Getting your ielts writing correction by a trained examiner is one of the effective ways to improve your writing. A graphic organizer is a visual display that demonstrates relationships between facts, concepts or ideas. A graphic organizer guides the learners thinking as they fill in and build upon a visual map or diagram. Whether you're looking to learn a new instrument or improve your photography skills, ehow Art will help you learn new abilities sans classroom. A guide to alphabets and languages, with useful foreign phrases, tips on learning languages, language-related links, multilingual texts, and much more.
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16.10 White-nose syndrome of bats
16.10 White-nose syndrome of bats
White-Nose Syndrome (WNS) of bats, caused by the fungal pathogen Pseudogymnoascus destructans, has decimated North American hibernating bats since its emergence in 2006 and is predicted to drive several species extinct. WNS was first detected in New York state in 2006 and was detected in Washington state in March 2016. Pseudogymnoascus destructans is endemic to Eurasia, where the disease is less severe, and it has a much lesser impact on bat populations.
Mortality from WNS differs substantially between North American species, even when they hibernate at the same sites. Some species declined more than 90% in the first year following WNS detection, whereas population growth rates in other species only decreased 8%.
Research has shown that in areas where the disease has been present for several years, bats first became infected when they returned to their winter quarters (their hibernacula) in the autumn, and both transmission and fungal growth on bats occurs primarily during winter once bats lower their body temperature and begin to hibernate. Despite markedly different mortality rates, most bat populations experience greater than 50% infection incidence; suggesting that variation in mortality is due to variation in response to infection. Mortality is thought to be due to a cascade of physiological disruptions which are reactions to tissue damage from fungal invasion. Deaths occurred approximately 70 to 120 days after infection. Variation between species in mortality was correlated with fungal loads of individual animals.
The fungal load is essentially the amount of fungus present in the animal; it can be measured by measuring the quantity of Pseudogymnoascus destructans DNA on bat skin using quantitative PCR on skin swab samples. It had already been established that there is a strong correlation between the abundance of P. destructans on bat skin measured from a swab and the extent of tissue invasion determined by histology. Although infection incidence was uniformly high in all species, fungal load varied a thousand-fold between species and statistically accounted for 98% of the differences in mortality rates. Fungal loads increased with hibernating roosting temperatures, with bats roosting at warmer temperatures having higher fungal loads and suffering greater WNS impacts. Pseudogymnoascus destructans growth increases with temperature across the range of hibernation temperatures commonly used by bats (approximately 1 to 12°C).
Consequently, differences in behavioural preferences between bat species, in particular their preferred roosting microclimate, determines the impact of a new pathogen. Understanding these behavioural/environmental influences on disease may allow control options that permit minimum intervention. Another interesting aspect of this story is that comparative genomics has demonstrated that the pathogen, Pseudogymnoascus destructans, is extremely sensitive to ultraviolet (UV) light, and to DNA alkylating mutagens. The reason for this being that the pathogen’s genome has lost a key enzyme in the repair pathway that normally contributes to repair of DNA damage induced by UV light. This feature might be exploited for treatment of bats with WNS (Langwig et al., 2016; Palmer et al., 2018).
Updated July, 2018
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Iran Zamin 2
Saturday, January 14, 2006
The Xerxes Canal
In 480 B.C., King Xerxes,(khashayar), of Persia ordered his men to build a canal a mile and a quarter long through a peninsula in Northern Greece- conceivably one of the biggest engineering assignments of it's time. The canal was critical to Xerxes' plan of invading Greece, a goal that his general, Mardonius, had unsuccessfully attempted 12 years earlier. Mardonius's fleet was destroyed in a storm while sailing around the tip of the peninsula, and Xerxes wanted to avoid a similar setback by building the canal. Xerxes went on to invade Greece, starting a brief period of Persian conquest in Europe. In the 2,500 year since, historians have debated whether the famed canal of Xerxes was really dug all the way from Coast to Coast. Some have doubted its existence, pointing to a rocky plateau that they argue would have made the construction an impossible task for workers of those days. Now, scientists from Britain and Greece have come up with what they say is conclusive evidence that the canal was indeed built. The structure now lies buried and a map has been drawn detailing the canal's dimensions ans courses. The findings confirms the description given in an account by the ancient Greek histiruan Herodotus, which some scholars have long regarded with skepticism. Buried under centuries of silt and alluvium, the structure is testament to remarkable military strategy, work-force management and civil engineering. It also tells of an eager king who was in such a hurry to conquer the World that he never thought of preserving the canal as a perminent waterway.Spanning about 100 feet at the surface, the canal was just wide enough for two war galleys to pass. Its sides sloped inward, forming a width of roughly 50 feet at the bottom, about 45 feet below the surface. The construction was as much of a feat of management as it was of engineering. Upon the completion of the canal, the Persian fleet made it safely to the Agean Sea, where it was joined by troops that had taken the land route from the North. The ships sailed on to Greece. Xerxes's soldiers stormed the Coast and advanced deep into Greek territory. They destroyed Athenes but eventually lost to Athenians in a battle that ended the Persian's fleeting imperial presence in Europe.
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The Story of How the Aliens of a Planet Save Themselves from Intruders
Chapter 1
Attack by Aliens from another Planet
On a far away planet, there live aliens that live inside houses that are made of plants with layers of leaves. The plant can remove its root from the ground and walk on its own. The special thing about this plant is that the aliens can carve out the inside of the plants and make it their home.
The benefit of staying in the plant is that it prevents enemies from spotting them. The plant is like a camouflage; no one knows someone live inside the plant. The leaves that form the layers of the plants can act as windows and the alien living inside can pull it up and down to open and close it.
One day, aliens from another planet decide to come and conquer the planet. They travel all the way from their planet to this planet with a mother ship. The mother ship could camouflage itself against anything. They make the ship camouflage as the sky of that planet which looks like a 3D ring around the planet. This is because the planet has one thick ring that can be seen in the sky at all times.
The mother ship parks itself in the sky and then opens the entrance door. When the door open, the long air stair starts to extend and reach downward to the ground surface. There is a red carpet in the middle of the air stair. So, when the air stair extends longer and longer downward, the red carpet also rolls down on and on. The air stair of the mother ship is flexible. It can roll and curl to swallow the round plant house where the aliens of the planet live.
When the air stair reaches the surface, it starts to scoop up the round plant house and gets them rolled back into the mother ship. When these plant houses are forced to roll into the mother ship, they try to run forward up the path and go back down to the planet’s surface.
Chapter 2
Alien Plants Fights Back Against Intruders
The aliens now know that their planet is under attack and they must do something to stop the attack. The plant house they are living in quickly uproot itself from the ground and join together to form two rows of tall vertical posts.
The alien living in one of the plant houses pours a special solution onto the root on the side of the plant so that it grows longer and longer until it becomes something like a hand. The root hand then reaches onto the air stair and pulls it hard to tear it down. When the stair gets torn down, the captured plants roll back down onto the planet surface.
The mother ship now releases a few smaller spaceships that shape like shields to attack them. The smaller spaceships shoot missiles but the plant’s root hands are fast in holding the missiles and throwing them back. This causes the small spaceships to explode.
One of the stacked plants then uses its root hand to capture and tie up the small spaceships that are still flying. Another stacked plants helped by using its root hand to complete the net pattern and they pull the net backwards counting one, two and three and hurl the net of small spaceships onto the mother spaceship so that it causes one part of it to become damaged.
The leader of the mother ship finally decides to surrender. He and all the subordinates of the mother spaceship come out through the small openings under the spaceships. They wore a device with spinning propeller on the head that help them to land on the surface safely. The leader pretends to make peace with them but he then aims up a rope gun with sharp barb on the end towards the plants.
Chapter 3
Bouncy Ball Hails Destroys Enemy Aliens
At this time, a hail storm starts to take place. The hail storm releases small and large balls of hails. These balls of hails are bouncy. The plant houses are protected from these bouncy hails because they have a natural bouncy surface.
If the hail balls hit the plant, they will bounce off quickly. The bouncy hail balls will melt at the heat of the day. The leader shoots the rope gun with barbs at the stacked plant but the plant’s root hand catches the rope. It pulls the rope and quickly turns round and round until the alien leader is now bound in coil of ropes and lying on the ground. Suddenly, a bouncy ball hail from the storm hits the alien’s leader and squashes him.
The stacked plant’s then uses its root hand to capture the subordinates one by and one and glues them onto the bouncy ball. The glue is poured by one of the planet’s alien resident. The bouncy ball rolls and rolls and squashes all the subordinates.
Meanwhile, the bouncy balls have been hitting the mother ship down and down until it drops onto the ground and explodes.
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Allison's Book Bag
Archive for the ‘Grades 6-8’ Category
Mariana Weber is so passionate about global warming that she used to regularly write letters to the president. Then she realized that his replies were all the same and that a co-worker had probably drafted a form letter for such requests as hers. Undeterred, Mariana decided to both form an organization for environmental protection and to write a book. For the latter, she enlisted her illustrator friend Joanna Whysner, whose colorful drawings add to the charm of The Global Warming Express.
Through an easy-to-read fantasy, Weber entertains while also making a plea for change. Earth is in peril. Several animals and two young people decide to join forces. They ride a magical train to the White House, where they hope their cry will be heard by the president.
The adventure begins in Antarctica, where an emperor penguin named The Fluff has just lost his mom, who died after swallowing a piece of plastic from the ocean. The girls also meet other animals whose stories engage while also drawing upon sympathies: a harp seal named Creamy who almost drowned when the ice she called home melted before she could learn to swim, a bear named Tomas and a salamander named Sally whose homes have been destroyed by fires caused by drought, a polar bear named Flora who found herself separated from her parents due to melting ice, a mountain goat named Edgar who has nowhere left to migrate, a caribou named Lauren who has no place to call home due to the destruction of muskeg, a duck named Zolo whose feathers have been permanently damaged by oil, a fish named Bobbi Sue whose aquatic home is toxic, and a rat named Zingo whose home is being destroyed by hurricanes that have become increasingly severe. One would be hard-pressed to read the tales of all these animals and not be stirred to action.
Weber has done her research. In her introduction, she explains why the Earth is heating up and why we need to slow down the effects. Through a parrot named Inoah, she teaches reading about multiple issues related to global warming such as the burning of fossil fuels, drilling of natural preserves, releasing of carbon monoxide into the air, and dumping of oils. And, on her resources page, Weber provides multiple links to articles and websites related to climate change. Anyone who is stirred to action by The Global Warming Express will have obvious reasons and solutions.
The Global Warming Express isn’t simply a cautionary tale. It’s also a fun story of a cross-country adventure where several animals and two young people visit unfamiliar places and face dangers such as fires and hurricanes. One minor complaint is I’m not sure why the train takes them into Canada, given that their mission is to plead with the United States president to pass environmental protection laws. While on this ride, the train becomes a character too. If the passengers are sad it slows down and even stops, but if the passengers are happy it speeds up.
In addition to writing a book, Weber started The Global Warming Express program. Its website explains global warming, tells how adults can help, and provides updates on small and big goals that young people in the group have made towards climate change.
From the ravaged tiny Polynesian island of Vaitea arises a hero and heroine for our times. Based on his ten years of Easter Island research, Edward Stanton has written an inspiring adventure about a brother and sister, their island, and how they saved it. In Wide as the Wind, Miru and Renga face tough choices and much hardship when they set sail to a distant island to find the seeds and shoots of trees that could reforest their homeland. Their return to Vaitea reaps romance and additional challenges in this teen historical novel.
Adventure is at the forefront of this tightly-written novel. Prior to embarking on their journey, Miru and Renga learn the sailor’s craft. Their grandfather teaches them to weave sails of pounded bark, cut full-sized paddles, make nets of mulberry cloth, and fashion birdbone hooks. He also teaches them to coast the island in a longboat, navigate by the sun, moon, and stars, recognize winds, currents, and constellations, and to fish. After recruiting a third crewman, the brother and sister duo set sail. On their journey, they brave the elements. The wind gusts. The sea roars. Supplies are washed overboard. The sun burns, parching their throats. They encounter sharks and their third crewman is attacked. Miru, Renga, and their third crewsman sail fifty-two days before finding land, and this is just the beginning of their adventure.
At the heart of Wide as the Wind also lies a theme. Years of tribal wars have devastated Vaitea. Tribes people who survived are now facing starvation. To save them, Miru must personally sacrifice romantic love, suffer injury and loss, and even risk his life. Even when they return from their journey to a distant island with the seeds and shoots of trees necessary to reforest their homeland, the tribal wars threaten to continue. Although some historical accounts suggest that extinction of natural resources of the real-life Easter Island inhabitants started long before internal conflicts, the latter certainly didn’t help. In basing his story on a real place, Stanton has crafted a parable that shows how mankind’s violence can lead to environmental destruction and even the end of a world.
Wide as the Wind has many other positives. The characters are realistic. Miru and Renga are likeable teens to which every reader can relate. Miru disagrees with his father’s choices, enjoys swimming with dolphins, and sneaks away to spend time with his girlfriend. The descriptions are vivid; the diction is strong. Here’s just one phrase for example: “He sat down with them on paving stones that glittered with brine and fish scales….” There are even moments of humor. One of the funniest is when birds poop on Miru’s head, just after he’s received the call to save his people. My one complaint is that I felt at times the action moved too fast and kept me at an emotional distance from the characters.
Author Edward Stanton has written eleven books. His fiction, poems, and essays have appeared in publications across the world. He is a professor of literature, and has won grants for his travel, research, and writing. Wide as the Wind is a worthy addition to his literary accomplishments. It has won the 2017 silver Moonbeam Award for Young Adult Fiction and the 2018 silver Feathered Quill Award for Teen Fiction.
I believe no one should be labeled as ‘crazy’ for loving a pet.—David Williams, MIC
Men with Cats: Intimate Portraits of Feline Friendship is a fun collection of photos and stories by David Williams that breaks the stereotype that only crazy ladies care for cats. Williams himself is a freelance photographer who lives in New York with his wife and their two cats. Men With Cats: Intimate Portraits of Feline Friendship was recognized as a New York Times Best seller shortly after its release in 2016.
Each two-page spread of this 140-page delightful photo book consists of a professional photo, identification of the male cat owner and his cat companion(s), and a quote that highlights the feline friendship. How each met differs: A mother cat followed Louis home; A burned cat slated for euthanasia was rescued by Al; Cats abandoned at an auto shop catch Alex’s attention. How the bond developed is unique: Brent loves how his cat jumps on his chest, kneads his paws in his beard, and licks his face; Reuben appreciates how relaxed his cat is and tries to emulate that lifestyle; Dennis admires the array of sounds his cat will use to communicate, with his favorite being a chirrup that acknowledges his presence. The way the men describe the friendship devotion varies: Benn refers to his relationship with his cat at being like an old married couple; Brian jokes that his cat is a dog except evil instead; Dustin shares that when he and his cat make eye contact there is a deep inner connection.
Photo books are not my typical fare. I’m more of an information sort of reader. One of my favorite parts of Men with Cats: Intimate Portraits of Feline Friendship is the section labeled “What is the hardest part of cat ownership?” I wanted to see several other spreads like this. But I must admit that a couple rereads of Men with Cats: Intimate Portraits of Feline Friendship revealed more than I expected about living with cats.
Williams started this photography project back in 2009 not only to shuns stereotypes, but also to celebrate feline friendship. In his preface, he expressed the hope that his book would inspire readers to rescue and adopt pets or donate time and resources to animal welfare groups. Men with Cats: Intimate Portraits of Feline Friendship certainly increased my appreciation for the quirky and intense bonds that can exist between men and their cats.
A good owner is just anyone that shows love and compassion towards their pet — whether it be a cat, dog, or rabbit.—David Williams, Refinery 29
If you like cats, romances, and mysteries, check out Mayhem and Mystery at the Kitty Kastle by Malynda McCarrick. The downside is the writing could use some editing and polish. The upside is a portion of the proceeds from the purchase of this short fun read goes to support Midwest cat shelters.
Too many strange things were happening at the Kitty Kastle for anyone to dismiss them as just anyone’s imagination. First, there were the unexplainable noises such as that of footsteps when there’s no one else around. Then there was the lack of noise. On the fourth floor, especially in an old house, one should the wind or the rain but instead the build is sound proof. Third, there are walls that are located where they shouldn’t be and a foundation that doesn’t line up with the rest of the building. Finally, there are the gifts that mysteriously appear. The mystery is my favorite part.
One black cat knew that something was afoot and kept trying to provide clues to Jay Carpenter, the man hired to bring the shelter up to code. He’s also a growing source of comfort to Miranda, the owner of Kitty Kastle. She’s recovering from a messy divorce, but apparently can’t resist a hunk in a toolbelt. Jay turns out to strong in build and gentle in character. Soon, the two are dreaming up a multitude of ideas for how the building could be renovated. Moreover, because Jay knows the shelter couldn’t cover the cost of major repairs, Jay has volunteered to help for free. Just as important, a dog lover at heart, Jay is slowly being converted to a cat lover. The romance is unrealistic but does make for a light-hearted read, which we all need at times.
Finally, there are the cats of Kitty Kastle. They live in a dream shelter. Each floor has varying levels of padded condos. In addition, the walls have ledges and cubby holes in which the cats can play and hide. On the first floor is a central playroom, filled with climbing structures and tunnels for the cats to explore. There’s also a large kitchen with multiple refrigerator for the specialty foods and various medicines the cats would need. Finally, the owner lives on the premises and so she is available 24/7 to check on the feline residents. The shelter’s inhabitants serve as a pleasant backdrop and the mystery wouldn’t have been resolved without Minx.
Author Malynda McCarrick is Midwestern country girl who grew up with a love for books. She’s also an avid animal lover. One day, the arrangement of vendors at a cat show put her and The Cat House (a no-kill cat shelter) next to one another. Afternoon conversations between the two led to McCarrick taking an interest in The Cat House and eventually self-publishing a cat cozy dedicated to its hard-working volunteers. Run-on sentences, missed punctuation, and some stereotype characters diminished some of my enjoyment of Mayhem and Mystery at the Kitty Kastle. Otherwise, McCarricks’ novel served as an evening of escapism.
Before I started to blog, if you had asked me to name jobs that pets do, I could have named several … and all of them would have been related to dogs. Should I have even thought of cats, I might have pointed out their ability to catch rodent. Yet cats are much more clever and versatile that most of us give them credit. You just need to read Lisa Rogak’s Cats on the Job to discover not just one or ten but fifty ways that cats purr, mouse, and even sing for their supper. In her colorful and photo-rich book, Rogak shares well-written true tales of cats around the world who are happily earning their keep.
Through blogging, I had heard of a few famous cats. Granted most of them were known for their quirky looks or unique talents such as the ability to play a piano. But there were also cats who starred in movies and even those who had run for mayor. The more I kept my ears open, the more stories I heard. And so, I knew about cats in bookstores, hospitals, libraries, and train stations. I’d also glimpsed stories of the current trend of cat cafes. I highly enjoyed reading Rogak’s examples of cats performing these jobs, as well as multiple accounts of cats that catch rodents.
Rogak also wrote about a host of jobs that cats perform which are new to me. One is that of Acro-Cats, a group that is devoted to “promoting the mental and physical health benefits of cat training through clicker training…a positive reinforcement based training method”. Learning about them inspired me to renew my own efforts at clicker-training my cats, and seeing the circus act in-person is on my bucket list. Another story that piqued my curiosity is that of rescued cats in Australia that create paintings. I’m sure at least one of my cats would be up to the challenge! I also found intriguing the idea of catflexing, a fitness routine that involves exercising with a cat. One of my cats has already shown interest in this! Another notable tale is of Carlow, a cat who works at a firehouse. Anyone remember Esther Averill’s story The Fire Cat from their childhood? Sometimes there’s truth in fiction!
Aside from the quality writing and design of Cats on the Job, what stands out most to me is the broad scope of jobs that cats can perform. To name a few in America: In Washington, a cat named Sable shows up like clockwork twice a day to serve as a school crossing guard; In Michigan, two lucky cats serve as furniture testers; and in New York, cats have a long history of acting as hotel concierge. Rogak didn’t just limit her tales to American cats either: In England, a toy company hired a cat to guard its warehouse of toys; In Great Britain, a cat named Jessi helps an autistic boy to express himself. In Japan, a cat named Iemon serves on the police force and helps fight crime. For some of these positions, it may seem obvious how the cat does its job. For example, cats who test furniture are cats who are encouraged to scratch, bite, and jump on furniture to test its durability. For other positions, such as that of how a cat that serves on the police force, you’ll have to check out Rogak’s book to learn how exactly cats can fight crime.
Now that I’ve read Rogak’s book, if anyone were to ask me to name jobs that pets do, most of them would be related to cats. Cats on the Job is an informative and fun read about an idea which is gaining popularity. Working cats are both a way to help the homeless cat population and to develop comradery with cats.
Through email, I asked Rogak how she found out about the cats she profiled. Her answer?
“I found the cats online, in older books–many of them were sadly long deceased–and by posting queries online. There were several that didn’t make it in because there wasn’t enough information or the photos weren’t great.
“The occupational hazard of writing books about cats is that several are not going to be around by the time the book comes out. The train stationmaster cat died a few months before publication date… but I’ve also discovered that having their stories immortalized in the pages of a book is a great way to honor their memory.”
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Question Info
This question is public and is used in 1 group and 451 tests or worksheets.
Type: Multiple-Choice
Category: Suffixes
Level: Grade 6
Score: 7
Author: milissacrum
Last Modified: a year ago
View all questions by milissacrum.
Suffixes Question
View this question.
Grade 6 Suffixes
What does the suffix "est" mean?
1. past tense
2. action or process
3. to compare
4. having a lot of something
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Signalling at Sea
Shipping Wonders of the World
Signalling at Sea
The development of marine communications from the makeshifts of the sixteenth century to the fine art of to-day, exemplified in the revised International Signal Code of 1934
NELSON’S FAMOUS SIGNAL AT TRAFALGAR on October 21, 1805. Nelson sent his signal at the beginning of the battle in which he received his fatal wound. This photograph shows the signal on the wall of the Nelson Room at Lloyd’s. To-day ships carry complete sets of forty signalling flags. Ships of the Navy have, in addition, numerous naval code flags.
“WHEN you wish to assemble the captains of your ships or to to speak with them, you will put on the mainmast a square banner tied in a weft.” Such is the instruction of the Gunner of the King of France in the first sea signalling manual, published in 1543. Captains are further directed to place banners in different parts of their ships, to shout, blow trumpets and beat drums, and to “ hang out a flaming cresset ” at night, to communicate with one another.
From these crude beginnings signalling at sea has become a fine art, culminating in the revision of the International Signal Code in 1934, the flags of which are given in the accompanying coloured plate. Almost every ship carries a complete set, which consists of twenty-six alphabetical, ten numeral, three substitute flags and the answering pendant. Bars, stripes, crosses and other marks are so arranged that, should - the colours be indistinguishable, the flags are immediately recognizable by their markings in all conditions of daylight.
Besides being used as a decimal point when signalling figures, the answering flag has a variety of uses. The substitute flags are used to avoid the repetition of a letter in a signal. For instance, “A A A” in the code (meaning “1 point on the port bow”) would necessitate three “A” flags being carried; but, using substitutes, the first repeats the first flag in the group hoisted, the second repeats the second flag, and so on. Thus, “D H D L”, which is the code signal allotted to the Hamburg South American liner Cap Arcona, is signalled by using the flags “D H - first substitute - L”; while “A J J O”, which stands for Liverpool, is signalled “A J - second substitute - O”.
International code of signalsINTERNATIONAL CODE, SECOND MEANINGS
A-Undergoing Speed Trial; B-I am taking in or unloading explosives; C-Yes (affirmative); D-Keep clear of me. I am manoeuvring with difficulty; E-I am altering course to starboard; F-I am disabled - communicate with me;
G-I require a pilot; H-I have a pilot on board; I-I am altering course to port; J-I am going to send a message by semaphore; K-You should stop your vessel instantly; L-You should stop. I have something important to communicate; M-I have a doctor on board; N-No (negative); O-Man overboard!; P-(Blue Peter—in harbour.
(At sea—your lights are out); Q-My vessel is healthy. I request free pratique; R-The way is off my ship; S-Engines are going astern; T-Do not pass ahead of me; U-You are standing into danger; V-I require assistance; W-I require medical assistance; X-Stop carrying out your intention and watch my signals; Y-I am carrying mails; Z-Used to address or call shore signal stations.
9. British Pilot Signal. (Is also flown at the bow by ship which is flying pilot flag H, or No. 23.)
10. Engines going astern.
11. The Blue Peter - vessel about to sail.
12. Quarantine Flag.
13. International Code Pilot Signal (P.T.)
14. Customs House Flag.
15. War Department Flag.
16. Distress Signal. (Letters N.C. of International Code.)
17. Distress Distant Signal. (Seldom used.)
18. Admiral of the Fleet - when flown at the foremast head. (See also
No. 1.)
19. Admiral.
20. Vice-Admiral.
21. Rear-Admiral.
22. Commodore’s Broad Pennant.
23. British Pilot Boat Flag.
24. Blue Ensign, flown by Fleet Auxiliaries.
25. Canadian Merchant Ensign.
26. Australian Merchant Ensign.
27. Royal Mail.
28. Cone warning of Northerly Gale.
29. Cone warning of Southerly Gale.
Where a signal contains three similar letters, it is given in this way: “S W S S”, standing for the Greek ship Zannis L. Cambanis, would be hoisted as “S W - first substitute - third substitute”.
To acknowledge a signal the answering pendant is hoisted “close up” - as far as it will go - then lowered to the “dip”, and the next hoist is made by the ship transmitting the message, so as to be ready for hoisting “close up” in acknowledgment of the next part of the message. Should a ship be unable to read a signal she keeps her answering flag at the “dip” and herself hoists a signal such as “U W” - “I cannot distinguish your flags”. The answering pendant is hoisted at the conclusion of a message.
The code is divided into single-letter signals, two-letter, three-letter and four-letter groups, the code book being arranged so as to facilitate easy reference either to groups of flags or to their meaning.
Single-letter signals, which are for urgent communications, are:
A - Undergoing speed trial.
B - Taking in or unloading explosives.
C - Yes.
D - Keep clear of me.
E - I am altering my course to starboard.
F - I am disabled. Communicate with me.
G - Want a pilot.
H - I have a pilot on board.
I - I am altering my course to port.
J - I am about to send a message by semaphore.
K - Stop your vessel instantly.
L - Stop. I have something important to communicate.
M - I have a doctor on board.
N - No.
O - Man overboard!
P - (in harbour) - All persons to repair on board as the vessel is about to proceed to sea. (Hoisted at the foremast head, the “Blue Peter”).
P - (at sea) - Your lights are out, or burning badly.
Q - My vessel is healthy. Request free pratique.
R - Way is off my ship - feel your way past me.
S - I am going full speed astern.
T - Do not pass ahead of me.
U - You are standing into danger.
V - I require assistance.
W - I require medical assistance.
Y - I am carrying mails.
Z - Calling shore station.
SUBMARINE SIGNAL DIRECTION INDICATORP” followed by four numerals indicates latitude and longitude, so that “P 1025-P 5036” means “Latitude 10° 25’ - longitude 50° 36”.
“T” followed by figures represents time, reckoned on the twenty-four hours system, thus, “T 0230” means “2.30 a.m.”, “ T 1430” means “2.30 p.m.”.
“X” followed by numerals is used to signal bearings. “X 90” means “Bearing 90 true”, and can be used with other signals.
SUBMARINE SIGNAL DIRECTION INDICATOR. This comprises submarine signal receiving and distance-finding equipment. By receiving wireless signals and the submarine bell from a transmitting station, a ship’s distance can be accurately measured. This is done by comparing the difference in time taken to receive the two signals.
Two-letter groups are arranged under headings in the code book in accordance with the following examples:-
B L - “Aeroplane is down in position indicated and requires immediate assistance”.
B Y - “I am forced to alight. Stand by to pick up crew”.
G F - “Buoy is awash and difficult to locate”.
G K - “Buoy you are approaching is not in its proper position”.
Heave To
O L - “Heave to or I will open fire on you”.
S A - “What is the name of the vessel or signal station in sight?”
Y Q - “Barometer is falling”.
Y R - “Barometer is rising”.
Three-letter groups indicate points of the compass, bearings, times, and tenses of verbs, and so on.
Geographical names are arranged as four-letter groups, beginning with “A”:
A A A S - Aberdeen.
A C D U - Brighton.
A F C Z - Dungeness.
A G J V - Glasgow.
A G O V - Gravesend.
A J M F - London - King George Dock.
A M P M - Plymouth, etc.
Four-letter groups are allotted also to ships, the nationality of which is indicated by the first letter of the group, for distinguishing purposes.
THE MORSE CODE is in general use throughout the world
THE MORSE CODE is in general use throughout the world. This is a simple code, based on a combination of dots and dashes. The most frequently used letters are the shortest in Morse - thus, E is one dot, T is one dash. The code is transmitted by numerous methods, including the “buzzer”, flag, searchlight and lamp.
The distinguishing initial letters of the principal maritime nations are:-
G - Great Britain, also M.
K - United States of America, also N and W.
D - Germany.
F - France.
J - Japan.
I - Italy.
L A - L N - Norway.
P A - P I - Holland.
Thus, Aquitania is “G L R Z”, Homeric “G D L J”, Bremen “D O A H”, and Atlantis “G L T M”.
Ships’ signal letters and wireless call-signs differed at one time, but now vessels use their wireless call letters when flag-signalling or otherwise transmitting their names. Those not equipped with wireless are given the call-sign they would have if they were so fitted.
Flags and Their Meanings
Flags and Their Meanings
1. Union Flag, flown at the bow by all warships when at anchor.
2. White Ensign, flown by H.M. warships and yachts of the Royal Yacht Squadron (R.Y.S.).
3. Blue Ensign - R.N.R. ensign, flown by merchant ships commanded by R.N. retired and R.N.R. officers, in certain conditions, and by approved members of certain yacht clubs.
4. Red Ensign, flown by all other merchant ships.
5. Royal Standard.
6. Admiralty Flag.
7. Trinity House Flag.
8. Lloyd’s Ensign, flown at signal stations.
Should a ship wish to transmit a message which cannot be conveyed by the existing code, but must be spelt out, as with a name and address, the answering pendant is hoisted over the letter “E”, meaning that the letters shown after it are to be taken as spelling a word, and not as code signals.
Answering pendant over “F” indicates the end of a word, or a dot between initial letters; and the answering pendant over “G” means that the spelling is concluded, and that the subsequent flags represent code signals.
For example:
Message: “ Please inform owner - William Thomson, Liverpool, expect to arrive Tuesday”.
The “hoists” would be:
H R B (from code) -
“Please inform owner”.
Answering pendant and E - Alphabetical letters follow.
W I L - third substitute - “Will”
I A M - “iam”
Answering pendant and F - End of word.
T H O M - “Thom”
S O N - “son”
Answering pendant and G - End of spelling.
B I R (from code) -
“Expect to arrive”
A J - second substitute O - “Liverpool”
P K - second substitute - “Tuesday”.
The answering pendant is then hoisted to indicate that the message is finished.
One-letter signals are used also to communicate between vessels towing and being towed. “A”, shown by a ship towing, means “Is the towing hawser fast?” and the same flag, by the ship towed, “Towing hawser is fast”.
There are several pilot signals. The code flags “G” or “P T” indicate a “I require a pilot”, as does the Pilot Jack (the Union Jack with a white border) when hoisted at the fore. By night a blue light shown every quarter of an hour, a white light frequently flashed just above the bulwarks, or “P T” in the Morse code is used for the same purpose.
In the Channel, where pilot cutters of several nationalities await incoming ships, blasts on the whistle or flashes with a lamp show the port for which a pilot is required. Five blasts or flashes, or a red over two white lights, means Antwerp; a long-short on the whistle or white light over red, London; four blasts or flashes, or two vertical white lights, Rotterdam; three blasts, or a red light over white, Amsterdam; and six blasts or flashes, Dunkirk.
SIGNALLING IN H.M.S. REPULSEShips entering port show the “Q” flag, meaning “My ship is healthy”. “Q Q” (“Q” and first substitute), “I am suspect - I have had cases of infectious diseases”, indicates that medical attention is required before pratique will be given, and “Q L” means “My ship is infected”, when strict measures will be taken to ensure that no disease is transmitted to the shore.
SIGNALLING IN H.M.S. REPULSE. Note the insulated leads of the wireless, the flag signals at the yards, the signalling searchlight for long-distance Morse messages, the mechanical semaphore on the lower bridge, and the bluejacket signalling with hand flags. H.M.S. Repulse, completed in 1916, has a tonnage of 26,500 and a speed of 32 knots.
Since January 1, 1933, British ships of over 150 tons register, engaged on oversea voyages, have been compelled to carry a signalling lamp. It is placed at the masthead or in some other conspicuous position, and the Morse code is used to transmit messages. A hand-flag also is used in connexion with Morse, a small wave of the flag indicating a dot, and a large sweep of the flag a dash.
The one-flag signal code is used with lamp flashes or whistle blasts in Morse, for conveying urgent messages.
The mechanical semaphore and semaphore flags are both in extensive use at sea to-day. The accompanying illustration shows this system, which every officer of the Merchant Service must know. Messages so sent are generally spelt out, and thus a code book is unnecessary.
In foggy districts submarine bell signalling is used and many lightships are fitted for the purpose. The sound travels through the water and is picked up by vessels equipped with a suitable receiver. Each lightship has its own “call”, sometimes its wireless call-sign, which is given out on the submarine bell or oscillator.
By receiving wireless signals and the submarine bell from a transmitting station, a ship’s distance can be accurately measured. This is done by comparing the difference in time taken to receive the two signals. Wireless waves travel faster than the submarine sounds, and the interval between the two indicates the distance away of the transmitter. Calculations are made also with wireless and ordinary sound fog-horns.
Another, but rarer, method of signalling is by groups of “shapes’’ - balls, cones and squares.
Storm signals are exhibited on the coast to warn seamen of approaching gales. A cone, hoisted point uppermost, or a triangle of lights, point uppermost, generally indicates a gale from the north, and the same signals reversed a gale from the south. This system is almost universal, but where easterly gales are to be expected the cone, when hoisted point uppermost, may mean a gale from that quarter. There are other local exceptions.
The United States have a different system. A red flag with a black centre is hoisted as a storm signal, with pendants to indicate the direction from which it is expected. A red pendant indicates from north-east to south, a white one from north to south-west. When a hurricane is expected, as frequently happens off the coast of Florida, two red flags with black centres are hoisted. At night, a red light is shown for easterly winds, and white and red light, for westerly. A “gale” generally means that wind is expected blowing at Force Eight in the Beaufort Scale - that is, a velocity of about forty miles an hour.
All too frequently distress signals follow those indicating a storm. The code flags “N C” mean “I am in distress and in need of immediate assistance”. A square flag, with a ball, or anything resembling a ball, hoisted with it, has the same meaning.
THE KEY AND THE LAMP are an integral part of Morse signalling equipmentContinuous blowing of the siren or fog-horn, the firing of a gun at minute intervals, flames from a burning tar barrel, flaming paraffin-soaked rags and the firing of rockets are all recognized distress signals. There are, in addition, the ordinary Board of Trade signals of the flare type.
THE KEY AND THE LAMP are an integral part of Morse signalling equipment. On the right is the key, on which messages are tapped out by hand. The depression of the key completes the electric circuit. The lamp is attached to a prominent part of the ship. Since January 1, 1933, British ships of over 150 tons register, engaged on overseas voyages, have been compelled to carry a signalling lamp, which is generally fixed at the masthead.
Certain signals also are exhibited by lightships and lighthouses to call the attention of coastguards and lifeboat crews to vessels observed in distress. These generally consist of guns fired at regular intervals and of rockets.
A rocket throwing a white star indicates that the life-saving (breeches buoy) apparatus has been called out; a rocket with green stars, that the lifeboat is being manned. By day, a rectangular flag shows that the former is on its way, and a triangular red flag the latter.
When boats are observed trying to reach the shore (as from a wreck), the following signals are made to facilitate the dangerous task of getting boats safely beached in a heavy sea:
A flag or white light held steady - “You may land here”.
Flag or flare waved from side to side - “Keep off, dangerous to land”.
Flag or flare waved and pointed to left or right - “Land in the direction indicated”.
Two flags or flares held about fifty yards apart - “Land on this line of approach”.
All over the world ports have their own code of signSEMAPHORE SIGNALLING with hand flagsals made by balls, flags, semaphore arms and lights to control the entry and departure of vessels. The depth of water to be expected in the entrance to the harbour, or the conditions prevailing on a bar are shown for the information of ships approaching from seaward.
These regulations at Lowestoft (Suffolk) are typical of this class:
A black ball or green light - “Less than ten feet of water in the entrance”.
A red flag or red light - “More than ten feet of water”.
A red light on the swing bridge inside the harbour - “Navigation is obstructed”.
A green light - “Bridge is closed”.
A white light - “Bridge is open”.
Navies have flag-signalling codes of their own, which are used for transmitting orders and carrying out evolutions. Wireless has not replaced this old-fashioned method of controlling a fleet, since wireless can be “jammed” by an enemy; but flags cannot be interfered with and have a good chance of being seen by the ships concerned.
SEMAPHORE SIGNALLING with hand flags - generally blue and white - is a common method of sending messages when the receiver is not far away. Certain letters are basically linked: thus, in A, B, C and D, the flag held in the left hand is kept in one position; in P, Q, R and S, the right-hand flag is kept in one position; and so forth.
[From part 2, published 6 February 1936]
You can read more on “Buoys and Beacons”, “Day and Night Signals at Sea” and “Distant Signalling at Sea” on this website.
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Nonlinear Deployable Mesh Reflectors
Design, Modeling and Analysis
A reflector is a structural device that receives and reflects electromagnetic signals. A reflector normally has a dish shape as working surface and is supported by another structure (commonly a truss) behind. Unlike reflectors on the ground, when a reflector is installed onto a satellite or a space shuttle and used in space, many crucial requirements must be considered, one of which requires that the reflector has to be deployable. Because the size of a space reflector is usually much larger than the spacecraft that carries it, the reflector must be first folded into a small volume on the ground that can be stored inside the spacecraft, and then be deployed into the space after the spacecraft has been launched onto the designated orbit. After the deployment is completed, the reflector will produce and automatically maintain a working surface (aperture) with tolerant surface errors. Due to this particular feature, such structural devices are called deployable reflectors. As one of many types of deployable reflectors, deployable mesh reflectors have broad space applications, and have brought continuously interest in academia and industry in the past. Deployable mesh reflectors have been used in several renowned projects, such as ETS VIII for satellite communication, MBSAT for global broadcasting, “NEXRAD in Space (NIS)” mission for remote sensing and climate forecasting and GEO-mobile satellites by Boeing for mobile communications (Thomson 2002; Natori et al. 1993; Meguro et al. 1999; Im et al. 2003). Deployable mesh reflectors are also envisioned for many other applications such as high data rate deep space communications, Earth and planetary radars, and RF astronomy observations. Figure 8.1 illustrates a structure design for deployable mesh reflectors that has been considered by NASA engineers and studied in our research. The reflector is supported by the flat truss on the boundary and the working surface is constructed by the mesh and the front net. The nodes of the front net and rear net are connected by tension ties, where the actuators are installed. Those actuators properly adjust the length of the tension ties, so as to generate and maintain the desired working surface during the deployment and the in-space mission. According to the structural configuration in Fig. 8.1, the mesh reflector can be modeled as a nonlinear truss structure (shown in Fig. 8.2), whose elements can only sustain axial tension stress. The structure is fixed on the boundary and the working surface is formed by the truss elements. The tension ties are connected to the nodes, which provide the vertical external loads because of the symmetry between the front net and the rear net in the configuration under the concern. There are two crucial factors in performance assessment of deployable mesh reflectors: the aperture size of the reflector (mostly in term of the diameter) and the root-mean-square (RMS) value of the surface error. According to the antenna theory, larger-sized reflectors are capable of transmitting greater amount of data with higher resolution, and the smaller surface RMS error implies broader frequency bandwidth of the transmitted signals. The characteristic ratio, which is defined as the ratio of the reflector diameter to surface RMS error, is one of the key parameters to evaluate the performance of the mesh surface. Obviously, to increase the characteristic ratio, we can either increase the diameter of the reflector or decrease the surface RMS error; both of which, however, will enlarge the number of mesh cells, and increase the complexity and difficulty in design and manufacturing of this kind of reflectors. Therefore, development of large-sized deployable reflectors with small surface RMS errors, although in urgent demand due to the stringent requirements on surface performance to serve signal with high accuracy, has been a challenge for years.Previous investigations (Hedgepeth 1982a,b) have shown the performance limitation due to thermoelastic strain and manufacturing errors of materials in passive structure. It has been suggested that active surface (shape) control becomes necessary to improve the surface performance of deployable space reflectors for space missions and other applications. In this chapter, we present the results from our research project on developing the active surface control (ASC) architecture by using nonlinear modeling and analysis techniques.The remaining of the chapter is arranged as follows: Sect. 8.1 specifically states the objectives of the research. Section 8.2 presents the theoretical formulation of problem modeling and analysis. Then the numerical results and discussions will be provided on a sampled deployable mesh reflector in Sect. 8.3. Finally, Sect. 8.4 addresses some remarks on the progress of development of ASC architecture and the future research direction, and then concludes the chapter.
Fig. 8.1
Configuration of a deployable mesh reflector
Fig. 8.2
3D truss model of mesh reflectors
External Load Trust Region Quadratic Programming Problem Surface Error Truss Structure
This work was a result of the authors’ previous projects partially sponsored by NASA’s Jet Propulsion Laboratory.
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Copyright information
© Springer Science+Business Media, LLC 2012
Authors and Affiliations
1. 1.Department of Aerospace and Mechanical EngineeringUniversity of Southern CaliforniaLos AngelesUSA
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An Ancient Bond with the Land
Trade Fairs
Ceremonial Trading
Ceremonial trading began with the building of a canopy under which leaders from both sides performed a pipe ceremony. The Nuptadi/Nueta leader made a pile of weapons and other goods under the canopy, and put his pipe on top. The Nakoda leader made a similar offering, and covered it with a bison skull. A ceremonial pipe dance started, and people began to add goods to their community pile. The Nuptadi/Nueta added corn, beans, dried squash and sunflower seeds. The Nakoda added pemmican, prairie turnips and dried berries. Other goods included bison robes, fancy leather clothing, decorative materials such as shell or bone beads, bird and animal claws, weapons, and tools or the materials for making them.
Appointed officials kept track of people's contributions. When the piles were judged to be of equal value, the two groups exchanged the contents. Each contributor received an amount proportional to what he or she had given.
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Sir Francis Drake is one of the great heroes of British exploration. Early in his career, he engaged in piracy and illegal slave trading. In 1577, he was recruited to lead an expedition around the southern tip of South America through the Strait of Magellan, and helped open new trade routes that allowed Great Britain to compete effectively with the much larger Spanish Navy and the Spanish colonies that dominated the Atlantic coast of South America. He continued across the Pacific Ocean and around the tip of Africa and home to England, becoming the first Englishman to sail around the world. Drake also played a key role in the defeat of the Spanish Armada, which was threatening to invade and conquer England in 1588. Vastly outnumbered, Drake helped lead daring raids on the Armada while it was anchored in Spanish ports, destroying dozens of ships and sowing confusion and fear.
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True Grit Map Assignment Topics
How the Power of Persistence and GRIT Turned Innovative Ideas into Reality
By Jim Watkinson and Tom Nutile
Bound for a Big Deal in New York
He was on his way by train from Hollywood to New York, thinking he was going to make a great new deal for his fledgling Walt Disney Studios. It was the tail end of the Roaring Twenties, and a young Walt Disney, also in his twenties, was going to ask his backer for more money and a bigger share of the profits for his next animated feature. Despite the many doubters who believed people would not pay to see an animated film, Walt had put his studio and backer on the map with the success of his “Trolley Troubles” cartoon, featuring Oswald the Rabbit.
But while Walt made his way to New York City in February of 1928, his backer, Charlie Mintz, was going behind his back. Mintz saw little value in the Disney Brothers, after all, Walt could hardly draw. So he set out to create his own studio, convincing virtually the entire Disney crew of animators to join him in a new venture – Charles Mintz Studios. When Walt arrived, Mintz at first tried to bribe him by offering the unheard of sum of $1,500 a week for Walt to stay on as a figurehead President.
Walt’s prudent partner, his older brother Roy, who handled finances for Walt Disney Studios, urged him to just make the best deal he could to continue working with Mintz. Facing financial ruin, Walt wavered and considered accepting. But Mintz dragged the discussions out for weeks, avoiding meetings perhaps to increase pressure on the young Disney. Finally, after many counter proposals, Mintz told him that he could either join the new team and take less money for each cartoon, or go home. This would be a direct take-over of the Disney studio, turning Walt into a mere employee.
When the young cartoonist balked, Mintz played his trump card, pointing out that although Walt had created the character, according to the fine print in the contract, it was he and the distributing studio – not Disney – that owned Oswald the Rabbit. Walt now essentially had no studio – Mintz had stolen most of his animators – and no cartoon characters.
Stunned by the double betrayal of Mintz and his disloyal employees, Walt vowed never again to work for anyone but himself. It was a defining moment not only in the history of Walt Disney Studios, but in the history of American entertainment.
Riding back on the train to California, Walt thought. And he sketched. His mind alternated between fuming over what had happened, terrified by the need to start all over, and drawing ideas for a story featuring a new character. Almost every type of character was already used by other cartoon makers, but inspired by Charles Lindbergh’s solo flight across the Atlantic, he drew a story about a mouse that builds a plane to gain the attention of a girl. The new character had big round ears and looked a lot like Oswald. His name was to become Mickey Mouse.
This has become the story of widespread legend. The real creation of Mickey Mouse was almost certainly a mutual effort with Ub Iwerks, Walt’s chief animator. But whatever the origin of Mickey, he would develop into a character some say was much like Walt himself – he often failed, but always bounced back. When faced with a setback, he would get up, dust himself off, and start all over again.
Few who saw the young Walt Disney would have predicted more than middling success for him. Walt’s father never had much luck, shuttling the family about the Midwest in the early years of the 20th Century. Walt sometimes received rough treatment at the hands of his father for little or no justification. Still, he found a way to bounce back, often seeking solace in fantasy. Sometimes disconsolate at the treatment he received as a young boy on his family’s farm, he withdrew and sketched cartoon pictures of the barnyard animals. He shunned the traditional educational route and took classes at the Illinois Institute of Art, honing his drawing skills. He developed an independent streak, doing what pleased him, forsaking the safe path by working for himself or at a “risky” venture if he found it satisfying. When a stable factory job beckoned, he instead chose to work as an artist at the Kansas City Star newspaper. After only a few weeks at a commercial art studio, he ventured out on his own, starting a commercial art operation and, eventually, Walt Disney Studios. Over time, Disney learned to trust in his own judgment and his ability to come up with original, often innovative, ideas and story lines for his films and cartoons.
Turning Mickey Mouse into a success was to become a test of perseverance and faith. Although the break with Mintz was final, under the terms of the old agreement, Disney still owed his old partner three new Oswald cartoons. Producing these last cartoons meant continuing to work with some staff that would soon be leaving to join the Mintz crew. Fearing that Mintz would learn about Mickey and copy him, Walt had Ub work only at night on the new mouse series and had family members work in his own garage to turn Ub’s drawings into painted “cels” for the production process.
Two early Mickey Mouse cartoons were produced in this make-shift way and trial audiences laughed at the new character and his mishaps. But there were already many other popular cartoon characters and film distributors were reluctant to add another, leaving Walt without a way to get his product in front of movie-goers. Trusting in his own creative judgment, Walt had Ub and his animators begin work on a third Mickey Mouse cartoon called “Steamboat Willie.” As work progressed Walt was evaluating new technology now becoming available for adding sound to movies and he was convinced that this feature offered a way to make his character stand out among all the other cartoons.
Work began quickly to create the music and sound to the cartoon. But Walt wanted more than just sound. He insisted the music match up, frame for frame, with the action on the screen. In one scene, for example, Mickey bounces to the music every two beats and spins the wheel of the boat at the end of every second measure of music. And he breathes when there are pauses in the accompaniment. Such synchronization was unheard-of. Indeed, the first full-length talking picture, The Jazz Singer, had been released only the year before, in 1927.
Adding sound to the film dramatically increased its cost and Walt had to sell his car and re-mortgage their building to complete the musical work and other production requirements. But despite its groundbreaking approach to sound and imagery, cautious film executives still would not distribute it. With a finished copy in hand Walt called on everyone he knew in the industry, without success. Running out of time and money, Walt listened when a prominent local movie theater owner said distributors would be convinced only after seeing real audiences react to Steamboat Willy. Having already invested $15,000 to complete the cartoon and now deep in debt, Disney was willing to gamble and he agreed to let the theater show the cartoon at a very low price.
In November of 1928, Steamboat Willy premiered in just one movie theater and the audience immediately loved the spunky new character with its unique mix of imagery and sound. Following the advice of his publicist, Walt invited prominent reporters to see his creation and many wrote rave reviews about the spirited little mouse with the squeaky voice. Mickey was a smash hit and soon Disney Studios was producing a new Mickey Mouse cartoon each month. Within three years, over 1 million children were members of the original Mickey Mouse Club and the name had become part of the cultural lexicon.
Transforming Animation
As successful as Mickey Mouse was, the cartoons were still merely short pieces, each lasting no more than a few minutes and serving to prime the audience for the feature film to follow. Because of their limited length and modest purpose, the price that could be charged for each cartoon was modest, leaving the company with little money. This was made worse by Walt’s drive to continuously improve the quality of his product with new techniques and technology. With production costs always rising and their selling price low, the Company found itself always short of cash. And if there was anything that Walt hated, it was being unable to reach for a greater vision because of a lack of resources. He needed to find a way to apply his organizations capabilities to something with greater revenue potential.
Out of financial necessity then and with a desire to be taken more seriously by the entertainment industry, Disney began to consider an idea that had never been successfully tried by other studios, a full-length animated feature film. Many in the Hollywood community scoffed at the idea; this was 1934 and they were in the middle of a worldwide depression, it was hard to believe that people would pay to watch an hour and a half cartoon.
If creating Mickey Mouse was an improbable success, then producing Snow White was impossible. This was the biggest animation project in history. There were no benchmarks or guidelines, no wealth of experience to draw from anywhere. Could they find enough people with the right skills to do the work? Was it possible to create a production process to handle so much animated material? Could they find new equipment and technology to create a leap in image quality? Could the work of so many different animators, each having a unique style, be blended into a smooth visual presentation? At the core and perhaps most important was the question of whether animation could bring human emotion to life? Unlike past work at the studio, where short humorous skits were simply strung together, Walt saw Snow White as a transformation, a true to life artistic journey that would reach deep into the viewer, connect with their beliefs and pull at their emotions. Doing this would require more money than even Walt’s imagination could count; it was definitely a bet-your-company proposition.
The very thought of making history, of creating something never done before energized Walt and he collected together a tight band of hand-picked animators, writers and production people, while leaving the task of financing all this to brother Roy.
Production of Snow White
Although the Snow White story had existed in print and as a play for many years, turning the original story into a movie with engaging characters would take Disney more than three years.
Each day Walt would tell the story of Snow White to whoever he could get to listen. Often he would act out the parts himself, and with each retelling the characters would develop and the story would evolve.
Unlike a live action movie where film is used to record the actors as they play out the scene, what we see as animated film, consists of 1,800 individual hand-drawn pictures per minute (hand drawn in those days and sometimes called frames or cels). And each frame had multiple production steps, including the rough drawing, adding background details and coloring by hand, often redone many times as the story evolved through frequent rounds of edits.
Beyond the challenge of sheer volume, Walt wanted animation that would present a sense of movement and realism that had not been attempted before. But creating a movie in this style would require artists with a skill level that was beyond the ability of most animators. Disney would need several hundred of these artists and the only way to solve this problem was to hire and train people themselves.
Snow White had to grab hold of the audience and take them on an emotional journey that begins warmly as we first experience the innocence of the young Snow White, only to plunge downward as the evil queen seeks to destroy her, reaching bottom when the dwarfs find Snow White’s lifeless body, then rising upward with the queen’s destruction and soaring triumphantly as Snow White is brought back to life by true love. This was not a mere cartoon; it was a deep connection to the beliefs and values within the American psyche, reaffirming that good will triumph over evil in the end.
Day after day, Walt thought of nothing but Snow White. Pushing for perfection, he drove everyone hard, but none harder than himself. As work on the film stretched into its second and then third year, he often worked past midnight and the burdens took their toll. One evening after not returning home, his wife found him unconscious at his desk.
With no end in sight, and costs on the film rising to exceed $1 million, three times its original budget, industry insiders began calling the project “Disney’s folly.” But many who heard Walt’s story-telling firsthand, or saw an early clip were enchanted by Snow White and assured him of great success.
Finally, after more than three years of effort, involving the creation of 3 million individual images, the film was released in late 1937. Walt’s persistence was rewarded with sell-out crowds as Snow White quickly earned over $8 million in revenue, more than any film before it, and won an Academy Award. The move to full-length animated movies opened an entirely new market for entertainment and launched the Disney Company down a path that would eventually turn it into the family entertainment giant we know today.
Closing Thoughts
True to the fortunes of its creator, the Disney Company has ridden many ups and downs since Walt’s passing in 1966. Certainly the company seemed to loose its direction and energy with the loss of Walt, going through many years of mediocre films and middling financial performance. But while the Disney Company seemed to move sideways for a time, beginning in the early 1980’s a group of Disney cast-offs picked up Walt’s mantle of innovation, along with a passion for great story-telling and started an entirely new era in animated films. Using the power of computer generated images (pixels), Pixar Animation Studios again brought true-to-life imagery and emotion to the screen, with blockbuster movies like Toy Story and Finding Nemo. Now rejoined with the Walt Disney Company through a merger that put Pixar in charge of Disney’s animated films, its people have shown a continual ability to push the field of animation towards Walt’s dream of bringing stories to life. In the process they have won 22 Academy Awards, 4 Golden Globes and produced billions in revenue in an industry that had been written off for dead by many experts, but we’ll leave the story of this great innovative company for another day.
Regardless of the postscript, The Disney Company and its entire industry all started with a dream to carry the wonder of childhood to people of all ages. That dream fueled a great comeback, a comeback powered by, well, in the words of Walt Disney himself:
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In the six-and-a-half minute video below, Feminist Frequency‘s Anita Sarkeesian makes the controversial argument that True Grit‘s Mattie Ross is not a feminist character. Her argument revolves around an important distinction: the difference between admiring women for doing masculinity and admiring them.
Our instinct to see Ross as a feminist character comes from her performance of masculinity: she is aggressive, tough, and vengeful. But is the valuing of masculinity feminist? Some say no. Instead, such detractors might argue, a true feminist perspective involves not just valorizing women who do masculinity, but coming to value femininity. In fact, valuing masculinity over femininity might be part of the problem. On this blog, we call this “androcentrism.”
Here’s how Sarkeesian makes the argument:
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History Of Saffron
As a medicinal herb and dye, saffron use goes back more than 50,000 years to depictions discovered in prehistoric northwest Iran. Its extensive use and high value has been found consistently throughout history in areas ranging from China to Europe.
From the Sumerians´ use of saffron as a trade good to religious offerings in Persia, saffron began to spread in popularity and geography beginning around the 10th century BC. Alexander the Great used Persian saffron for infusions, cooking and bathing. Phoenicians traded it for use in the treatment of melancholy, while it began being used in Tamil for easing labor pains and religious rites about 2,000 years ago.
Greek history recounts voyages to Cilicia sometime after 1,600 BC, with the goal of seeking out the best saffron for use in perfumes, cosmetics, ointments and offerings.
Egyptians treasured saffron as an aphrodisiac and Cleopatra reportedly used it in her baths to help improve lovemaking.
Saffron was so popular in 14th century Europe that the theft of a single ship carrying saffron sparked the "Saffron War", which lasted 14 weeks, and later in Nuremberg the Safranschou code was enacted which made saffron adulteration punishable by death.
Saffron made it to America by way of Europe and began to be widely cultivated in Pennsylvania by 1730. High demand in the Caribbean spiked the value of saffron to equal that of gold until the War of 1812 when many merchant vessels transporting saffron were destroyed. Pennsylvania Dutch saffron continues to be a specialty trade today.
Cultivation Of Saffron
Planting Saffron
Saffron is propagated by dividing the corm offspring, or cormlets, and planting each individual cormlet. Corms are planted deeply; from 2.8 to 5.9 inches in loose, well-drained clay soil that is high in organic matter. Traditionally, organic matter is introduced through a rich layer of manure.Climate, planting depth and spacing are all very important factors in determining yield. Each commercial growing region has tailored these figures specifically to its unique environment. Deeper planting depths create higher quality saffron.
Climate for Growing Saffron
Saffron crocuses thrive in semi-arid, hot and sunny conditions. While they can tolerate cold and even occasional snow, saffron crocuses do better in warm, dry environments. In the Northern Hemisphere, south-sloping hills are ideal, with plenty of wind and soil drainage. Saffron plants thrive in full sunlight and will perform poorly in low light or partial shade. In the Kashmir region of South Asia, rainfall is adequate with about 45 inches average per year. In other regions, irrigation is necessary for the saffron crocus to do well. The timing of watering is critical to saffron plants: rain or water before flowering is ideal while much moisture after flowering can promote rot and disease, resulting in crop losses.Saffron crocuses need to be able to dry out between watering or problems with rot, disease and low yields can result.
Growing Regions
Iran is the largest producer of saffron, accounting for about 94% of the world´s saffron production. In addition to Iran, the main producers of saffron are Spain, India, Greece, Azerbaijan, Morocco, and Italy.There are smaller, highly-specific cultivars found in pockets of countries such as New Zealand, France, Switzerland, England, and in the United States, where Pennsylvania Dutch saffron has a dedicated, if small, following.Cultivars are known by the region they are grown in, and saffron connoisseurs will pay a premium for saffron grown at these boutique farms. Italy, for example, has its own renowned cultivar known as "Aquila", grown in one small valley of the Abruzzo region.In each of these growing regions, climate dictates the success and the potency of the saffron strains. Some are known for being mellow while others, like saffron grown in Iran, are known for being more potent.
Medical Use Of Saffron
Saffron has a versatile medical action, and the reputed healing properties of saffron are scientifically verifiable. The carotenoids as well as various essential oils have long been known in medicine. Saffron has both analgesic properties that act on pain of the body as well as mental pain. In addition, the diuretic effect is known and sweaty.Also saffron as a remedy for epileptic seizures and as a heart medication is used. Saffron is also suitable for strengthening the stomach and lack of appetite. The liver is benefiting from the gifts of saffron, mainly because of the slight bitterness. In whooping cough and other violent coughing spells saffron brings relief.Except in the pregnancy - Caution, possible miscarriage! - Saffron can be used in many situations to strengthen overall. But as with any remedy should be discouraged from an overdose - to poisoning by saffron are possible!
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Tips for Taking Field Notes
Professional and amateur scientists routinely take notes on their observations and experiments. Because the documentation of natural history information is important, birders should learn to take good field notes. Note keeping may enhance the skills of birders by forcing you to more carefully scrutinise a bird, helping you identify an unfamiliar bird, serving as a reference for your observations, and providing scientists with valuable information. Note keeping should begin by recording the date and location at the top of a page. Notes may include data on the species observed, number of individuals for each species, plumages, behaviours, natural history observations (e.g., nests, habitat, etc.) and descriptions of rare or unusual birds.
Birders who observe rare birds should document their sightings by photographs, if possible. Rare birds may also be documented by collecting for preparation as museum specimens or by tape recording their vocalisations, but this is rarely accomplished. In the absence of physical documentation, a thorough written description–taken in the field, not from a field guide–will often suffice to convince the committee. As detailed a description as possible should be written while observing the bird or as soon as possible afterward, and always before consulting a field guide. A good description should begin with the size and shape of the bird, and proceed to the colours or patterns of its soft parts (bill, eyes, legs), upperparts and underparts, preferably from the head to the tail. A crude drawing with colour or pattern labels is recommended (see Fig. 1 for the body parts of a bird). Information regarding viewing conditions should also be noted, including the date and time of the observation, the weather and light conditions, the distance from birds and optical aids used, other species present for comparison, and other observers present. Descriptions should be written as candidly and honestly as possible (see Fig. 2 for an example). It is a good idea to take note of why similar (and therfore possibly confusing) species were eliminated. After writing the description, discrepancies between what was observed and what appears in a field guide (birds often vary somewhat from illustrations) could be added to the description.
Observations of rare birds should be promptly reported to fellow birders and to the T&T Bird Alert so that others may have the opportunity to observe and document the birds’ presence. Furthermore, the details of rare birds should be submitted to the appropriate authorities and to the Trinidad and Tobago Bird Status and Distribution Committee for evaluation, preferably on the recommended Rare Bird Report Form. Keep in mind that an observer’s reputation is an important factor. A healthy dose of honesty and humility helps.
Selected References
Patterson, M. 1997. How to write convincing details.
Remsen, J. V., Jr. 1977. On taking field notes. American Birds 31:946-953.
Wilds, C. 1985. On taking a notebook afield. Audubon Naturalist News October:15.
Wilds, C., and R. Hilton. 1992. Emerging from the silent majority: documenting rarities. Maryland Birdlife 48:30-??.
Fig. 1. Commonly used terms for the body parts of a bird.
Fig. 2. Sample field notes of the first Wood Sandpiper (Tringa glareola) from Tobago, illustrating description and sketch. Field notes by Floyd Hayes.
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< previous
St. Lawrence's Church, Towcester
St.Lawrence Church
AEDICULEAn opening or shrine, often containing a statue, framed by a pair of pilasters or columns placed against a wall.
AISLEDerived from the Latin word ala meaning wing. Describes the part of the church running parallel to the nave and separated from it by an arcade or row of piers. Aisles were intended to provide additional space for the congregation, and in the medieval period, to accommodate the Chantry Chapel.
ARCADEA series of arches on columns or piers.
AUMBRYA cupboard or recess in which the sacred vessels, used for Mass or Communion, were stored.
BATTLEMENTAn alternating high and low parapet on a wall.
BOX FLUE TILESOpen ended box shaped tiles which were built into the thickness of the walls, behind the plaster, of a room heated by a hypocaust.
BOX PEWSeating enclosed by a high wooden back and ends, entered by a door which protected the occupants from draughts. Occasionally pews would be reserved for specific families and were lavishly furnished, sometimes including armchairs and a fire.
BUTTRESSA projecting support built against a wall to provide strength.
CAPITALA decorative element at the head of a column dividing it from the masonry, or shaft, supporting it. The decoration is often a useful guide to the period of architecture.
CHANCELThe eastern end of the church in which the main alter is placed. Derived from the Latin cancelli meaning lattice or screen, which separated the chancel from the nave. In medieval times the priest of the parish was responsible for maintaining the chancel, while maintenance of the nave and chancel screen rested with the parishioners.
CHANTRY CHAPELDerived from the French chanceries meaning 'to sing', a priest would be employed to sing masses for the well being of the founder in his life time, and for his soul after death.
CHEVRONA zigzag decoration carved on pillars or arches characteristic of Norman architecture.
CINQEFOILOrnamental tracery in the form of a five petalled flower.
CLERESTRYThe upper storey walls of the nave of a church, pierced by high windows.
CORBELA block of stone projecting out to carry the weight of an arch, beam or other feature.
CRYPTA vaulted underground room usually at the east end of the church, beneath the chancel. In medieval times the crypt was a stone chapel built beneath the floor of the church to hold the tombs of the deceased.
EARLY ENGLISHA style of architecture between c.1190-1275.
EMBATTLEDHaving battlements.
GALLERYAn upper balcony with seating overlooking the nave.
GNOMENThe metal (or wooden) pointer on a sun dial.
GOTHICPeriod of Medieval architecture prevalent in Western Europe from 12th to 16th century. Characterized by the pointed arch and large windows with ornate tracery. Can be subdivided into Early English, Decorated and Perpendicular.
HERRINGBONE PATTERNBricks or tiles laid diagonally with alternate courses in the opposite direction.
HUGHESHenry Hughes (1822 - 1883) Born in Shropshire, he was the son of a butcher, and worked as an apprentice at Ward & Nixon, stained glass manufacturers. After Nixon's death in 1857, Henry Hughes went into partnership with Nixon, working from Frith Street, London. Throughout the 1800's the quality of the glass had been a major limiting factor to designers. It was not until the late 1840's that a range of pot-metal coloured glass was produced that looked like medieval glass and Ward & Hughes were the first firm to use it.
Ward and Hughes were responsible for designing and erecting a large number of windows in the Diocese of Lincoln including Lincoln Cathedral, so it is no surprise that they were commissioned to design a window for St Lawrence.
HYMERSHarvey (Harry) Alexander Hymers of Chelsea, London. Erected windows in St Peter & Paul, Eye, Suffolk also St Mary's Northampton and St Andrew's Harlestone, Northants.
HYPOCAUSTRoman underfloor heating system. The floor is supported on pillars and heat from a furnace is circulated via flues to heat house or bath.
INTERLACEAn abstract pattern characteristic of Anglo-Saxon decoration.
KEENEJames Keene started founding in Bedford in 1618, and moved to Woodstock in 1622. He was sometimes helped by his father Humphrey.
LECTERNA desk to support the books from which the lessons are read in church.
LIGHTSThe subdivision of the glazed area of a window.
LOZENGEA diamond shape decoration found carved on pillars and arches.
MANDORLAAncient symbol of two circles coming together, used to describe the coming together of heaven and earth.
MINTONHerbert Minton of Stoke On Trent was the most important of the early Victorian tile manufacturers, perfecting the process of inlaid tiles (also misleadingly known as 'encaustic'). He worked with A.W.N. Pugin who designed churches and domestic interiors all over the world with his encaustic tiles.
MOOREA. L. Moore (Arthur Louis Moore 1849-1939), Glass Painters & Decorators, 89 Southampton Row, London WC. The company was renamed to A. L. Moore & Sons in 1896.
NAVEThe western and main body of the church, flanked by the aisles. The nave was traditionally the responsibility of the parishioners in medieval times.
NICHEA recess in a wall for statue.
NIMBEDA nimbus is a halo of light or mist around an object.
NORMANA style of architecture between c.1066-1190.
OGEEA double curve bending first one way and then the other. An 'ogee arch' has two curves meeting at an apex.
OPUS SPICATUMWalls or floors made of quite small elongated tiles or briquettes, laid in a fishbone pattern.
PELICANIn Medieval Europe the pelican was thought to be particularly attentive to her young to the point of providing her own blood when no other food was available. As a result of this it has become a symbol for self-sacrifice.
PERPENDICULARA style of English Gothic architecture between c.1350-1550
PEW RENTINGThe order of seating in the seventeenth and eighteenth centuries reflected the rigid social structure of that period. Box pews, which provided a certain level of privacy and comfort, would be rented by the wealthy families. Benches crowded in the aisles and galleries were provided for those who could not afford to pay for their seats.
PIERA support which is often square rounded or octagonal.
PILAEHypocaust tiles which were cemented together to form small columns called pilae. The pilae raised the floor so that hot air could pass underneath.
PISCINAA shallow basin with a drain for washing sacred vessels, usually set into a wall to the south of the altar
PULPITFrom the Latin pulpitum meaning scaffold, platform or stage from which the priest would deliver the sermon
QUATREFOILOrnamental tracery in the from of a flower with four symmetrical petals
ROMANESQUEThe style of architecture prevalent in Western Europe. In England often called Saxon or early Romanesque (600 -1066), and Norman or English Romanesque (1050 - 1189).
ROOD LOFTIn medieval times the body of the church (the nave) was divided from the chancel by a screen. This defined the part of the church, which the parishioners were responsible for repairing (the nave) from the chancel, which was the responsibility of the priest of the parish. The rood loft or platform was supported above the screen and may have been used to accommodate the organ or choir. It was protected front and back by panelling and the great rood or crucifix would have been fixed to the front.
Many rood lofts and crucifixes were destroyed at the Reformation. All that remains in St Lawrence are the stairways to access the loft.
ST LAWRENCESt Lawrence was born in Spain in 225 and died in Rome on August 10th 258. According to legend he was burned to death. In religious paintings he is depicted with a grid iron symbolizing his martyrdom.
SHAFTUpright member of a column.
SPONNEArchdeacon Sponne was Rector of Towcester from June 1422 until February 1447, previously rector of Heavingham and Blofield in Norfolk.
VOUSSOIRA wedge shaped stone used in an arch
The St. Lawrence section of the web site was researched by Liz Davies. The web editor was David Wilcock. Acknowledgements and a full list of sources can be found by clicking on Sources.
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Although we might have an idea of what the choke is, often we don’t really know how it really functions or what its exact purpose is. Since the functioning of your car’s engine might depend on it, it is a great idea to have a precise idea of what the choke is and how it functions.
One first and brief definition of the choke tells that it is a valve which has the aim to control the carburetor air flow of a gasoline car’s engine. This way, through the choke we manage and reduce the air supply of the car’s engine and therefore have control over it. This is very important due to the relationship between the engine’s air amount and the fuel which can enter it.
Through the restriction of air, the choke allows fuel to go into the engine, allowing it this way to start. This is what we do when we are starting our car and it is cold, the choke allows a great amount of fuel to go into the engine by reducing the air, and this is how cold engines can start without difficulties.
The choke functions by controlling the air at the mouth of the carburetor. The carburetor’s mouth is where this valve is and where it controls the air amount of the engine. Due to its function, the choke is indispensable for gasoline engine’s to start functioning.
The choke is considered part of the motor transmission system. It works in direct connection with the engine and the carburetor, and their correct functioning depends in its work. It has such a great importance that you might not be able to start the car if it isn’t working properly or it is broken any way.
There are electric chokes as well as the regular chokes. The difference between a choke and an electric choke is that the choke functions through a tube while the electric one uses electricity. But, no matter what the choke’s kind is, they all have the same aim in common and they all allow a cold engine to start.
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1.1 Written Text Essay 2017 Question 3: Describe a place or time where a character felt very comfortable of uncomfortable in the written text.
Explain how techniques helped you to understand the character’s reaction.
Note: Techniques could include figures of speech, syntax, word choice, style, symbolism, structure, or narrative point of view.
In the book “Touching the Void”, written by Joe Simpson, Joe encounters a very uncomfortable moment when he shatters his knee joint. Joe sets out with his climbing partner, Simon Yates to climb an unclimbed route in the Peruvian Andes on the mountain Siula Grande. However, the two men are inexperienced and fail to take this factor into account. In addition, they are far from help. When things start to go wrong, they are put in an uncomfortable situation that possibly could have been avoided if help was nearby. Joe, along with Simon are able to help the reader understand their reactions towards Joe’s leg break, as well as the difficult situation they are in, through the various language techniques they use. This includes foreshadowing, emotive language and personal perspective.
Joe foreshadows danger and discomfort in Chapter 3 – Storm at the Summit: “For the first time we could see the summit…it looked like bad weather was on the way.” Joe’s use of foreshadowing creates a negative atmosphere and gives the reader an idea that he and Simon are about to encounter struggle. Even though the two men are nearing the summit, they still have a whole climb ahead of them: the descent. Some may think the descent is easier than the ascent. However, most climbing accidents occur during the descent, so Joe and Simon are still far from safety. Joe also predicts bad weather, and this will test his and Simon’s skills to the absolute limit. Strong wind, heavy snow and flat light can suddenly change a pleasurable climb into a nightmare of an experience. Add in an injury, and there can be a potential disaster on your hands. As readers, the quote can teach us that in climbing, things can be going well, before a sudden change in weather can cause the situation to make a turn for the worse. It also shows us the human nature of predicting danger, a form of survival instinct so we can get ourselves to safety. Joe’s prediction of danger means he can be ready for facing adversity and think of how to manage the difficulty, so he can make the best decisions possible (e.g. picking the safest route down the mountain) while he is still in safety.
Joe shatters his knee joint during the descent in Chapter 5 – “Disaster”, and he describes the event with the use of emotive language. The injury puts both of them in a highly uncomfortable situation. This can be shown when Joe says: “I felt a shattering blow in my knee, felt bones splitting and screamed.” This quote puts the reader in ‘Joe’s shoes’ and the use of emotive language: “shattering, splitting and screamed” can make them empathise with his pain (ie. can imagine the pain in their own leg). I for one, found it interesting that Joe and Simon were both affected in different ways from this event. Simon is put in a position of immense responsibility, whilst Joe is in a state of extreme agony; affecting his physical abilities for climbing, as well as his mental abilities such as decision-making. Joe’s injury makes his leg practically useless and one could argue that Simon now has Joe’s life in his hands. This passage of the text shows that we can encounter moments of extreme pain and discomfort in our own lives, caused by being in an extreme environment. The quote particularly resonates with those who have broken their own leg. Joe’s injury also reflects the human’s reaction to pain: the emotion (shown with emotive language), the severity and the feeling of total weakness.
In terms of climbing in a remote, mountainous environment, an injury as severe as a broken leg can often lead to death. Joe realises this, and uses his personal perspective to talk about the issue. “Dying had seemed so far away and yet now everything was tinged with it.” The language Joe uses shows his feelings towards the moment in his immediate thoughts of survival. The quote shows how suddenly one’s attitude can change when they are put in danger. Joe has been forced outside of his comfort zone, and climbing down Siula Grande has now become a fight for survival.
Simon uses his own personal perspective in the book to give the reader an idea about his initial thoughts towards Joe’s leg break. “You’re f**ked, matey. You’re dead…no two ways about it!” Simon’s immediate reaction on the situation they are in, comes across to the reader as very negative. Simon thinks Joe is going to die. His use of strong language also adds emphasis to his thoughts. This particular area of the text shows that when we see someone in a difficult situation, we can automatically think ‘that’s it’. It also shows us that our emotions can get in the way of our logical thinking. Simon becomes ruled by his emotions, and this means he is not able to think of any possible solutions to the issue at that present moment in time.
The book “Touching the Void”, by Joe Simpson shows how decisive an uncomfortable moment can be on a climber’s situation. This is highlighted when Joe shatters his knee joint. Joe’s injury puts him in an unfit physical state, and overalled by the pain, he struggles to make rational decisions. Simon is therefore put in a great deal of responsibility and becomes in charge of two lives rather than one. Joe shattering his knee joint teaches the reader that in the outdoors, things can happen when you least expect it. It also shows the reader the importance of being prepared in the event of a survival situation so immediate help can arrive. Joe and Simon failed to achieve this, which led to an uncomfortable situation that could have been avoided if the two men had planned ahead. Joe’s injury also has a lesson for all of us; it is often in human nature to think ‘everything will be fine’, before thinking about the possible risks around the situation – as if we imagine it will go away. For Joe and Simon, the risk became a reality, and therefore had to face the consequences. The author: Joe Simpson uses the language techniques mentioned to add significance to his, and Simon’s reaction of Joe shattering his knee joint.
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1. Alex, overall this is an effective essay. Well done for including multiple judgements throughout the argument. It would be difficult to write an essay of this length in the exam so I would suggest leaving out least “Joe’s perspective” and the repetition of ideas in the conclusion. “Simon’s perspective” is a stronger example of purposeful language/structure to convey ideas, and a number of the judgements made in the conclusion have been stated or implied in the points. You will have to make the call on this. Well done for this prep.
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History of Alaska
It is due to the extraordinary geographical location of Alaska that the state’s history differs greatly from that of most other parts and states of the US. In 1741, the Danish-born explorer Vitus Bering, working as an officer of the Russian Navy under Emperor Ivan VI, was the first to land on the Southern coast of Alaska, near or on Kayak Island. Russia quickly took control of the area and soon thereafter realized that this possession was a lucrative asset.
Alaska check
Shortly after Bering’s first trips to Alaska, trappers from all parts of Europe followed him to the unknown lands, so that a little later, around the turn of the century, it was de facto the Russian-American Company that administered Alaska. The USA slowly realized that Alaska could be of great value to the country and thus in 1867, on the initiative of Secretary of State William Seward they purchased the vast area for 7.2 million dollars from the Russians, paying by check (photo).
Despite the investment, large parts of Alaska remained unexplored and administration duties switched from Army to the US MInistry of Finance to the Navy. Only in 1884, Alaska was organized as a Territory, but still Washington DC paid little attention to their possession. However, this should change soon thereafter.
Gold was found at the Yukon River in Canada in 1897 and this made many people try their luck in Alaska. As it turned out, there was not only gold, but also a number of other natural resources could be found there, for example crude oil, which was discovered in 1968. Apart from this, natural gas, silver, coal, copper and a number of further resources can be distracted here and form the backbone of Alaskan economy. However, Alaska is at the same time a unique habitat, so that often ecological and economical concerns and interests clash in public.
In World War II, three islands off of the Alaskan coast, inhabited by Aleutians, were occupied by Japanese forces. The Americans won the islands back in May 1943, but paid a high price with more than 3000 fallen soldiers. The increased military presence led to a hike in population numbers in the 1940s. In 1959, Alaska became a US state.
On Good Friday of 1964, the Southwest of Alaska was hit by an earthquake with a magnitude of 9.2. There were 139 casualties, mostly caused by the ensuing tsunamis. Another catastrophe struck Alaska in 1989, when the oil tanker Exxon Valdez ran aground and lost millions of liters of oil. Hundreds of thousands of animals died as a consequence and up until today, oil production remains a hotly disputed issue.
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Hydrogen is a leading contender for the energy source of the future. However, the technology behind its delivery and deployment is nowhere near consumer-level yet. Hydrogen-power scientists are still working out issues to make their solutions safer and more efficient. One of the factors holding hydrogen back is the puzzling inability to get the substance to stay in the storage media intended for it.
Palladium and Hydrogen Storage
While it has been established that palladium is probably the best compound for hydrogen storage, this substance's actual ability to retain these tiny molecules (i.e., H2) is sub-optimal.
Pure palladium (Pd) attracts more H2 to its surface than other candidate storage media like gold. However, in order to store the hydrogen, it needs to sink deeper into the Pd’s surface. This process, known as chemisorption, followed by adsorption, has failed in recent studies.
However, when tiny amounts of gold are involved in this Pd-H2 interface, the situation can be different. Some Pd-Au alloys have demonstrated significantly greater H2 absorption compared to Pd alone. This is because the ‘adsorption’ (or H2 retention) step within Pd-Au is superior compared to that for either of the pure metals.
However, this is a finicky effect in need of extreme fine-tuning; add too much gold and the adsorption levels trend back toward those associated with Pd. The real problem there was that scientists did not know exactly why this happened.
A newer study, led by researchers from the University of Tokyo, compared the hydrogen-retention properties of gold-palladium alloys with those of pure palladium. The alloys were prepared in the form of Pd surfaces at a nanometric scale. Just a few atoms were removed from the topmost layer of this surface and replaced with gold.
How gold atoms integrate as a sub-monolayer into a Pd surface. (Source: K. Namba, et al., 2018)
This resulted in a sub-monolayer, in which the ratios of Pd to Au atoms were along the lines of 70:30 (i.e., an alloy with a 0.3 gold monolayer). The scientists confirmed that this 0.3 alloy was superior in terms of adsorption compared to Pd alone, whereas their chemisorption profiles were virtually identical. These values were quantified using thermal desorption spectroscopy (TDS). They were taken in the presence of H2 bombardment (measured in units known as langmuir) of 100 to 1000 langmuir.
TDS spectra of chemisorption (β), adsorption (α1) and H2 ‘loss’ (α2) associated with different Au-Pd alloys and pure Pd. (Source: K. Namba, et al., 2018)
Why Pd-Au Alloys?
The effect of the gold sub-monolayer on H2 retention can be explained by a number of factors, which the scientists also discussed in their paper.
The researchers noted that adsorption depends on the electronics within the surface of the material in question. An angle-resolved photoemission spectroscopic (ARPES) analysis of pure Pd and a representative (0.48) Pd-Au surface revealed that Pd exhibited a solid band at 0.3 electron-volts (eV) below the Fermi line (E^F), whereas Pd-Au could achieve corresponding solid bands of up to 5eV. The alloy could also display additional intensities at up to 7eV.
This broader range of electron energies was attributed to the properties of the gold in the alloy and may have been conferred by the s, d and p shells of its atoms.
These findings led to the adoption of a 0.3 or 0.5 sub-layer conformation for the majority of the study.
This also gave other results relating to the adsorption performance of the alloy. For example, the scientists reported that the intermittent inclusion of Au atoms into the top layer of the Pd surface exerted changes in the layers immediately below (which take the form of a lattice made of interleaving octahedral and tetrahedral layers of Pd atoms; therefore, the first layer is designated O1, the second T1, the third O2, and so on). This caused the electronic energy in the layers, and in the transitions (e.g., O1 to T1) to change.
This energy is known as the 'penetration barrier,' as it partially prevents H2 adsorption past O1. Accordingly, the O1-to-O2 barrier in the 0.5 alloy was reduced by 0.16eV compared to that in pure Pd, as was the O1-to-T1 barrier (by 0.28eV). These values were measured using density-functional-theory (DFT) modeling.
The results may also have helped to explain why too much gold disrupts adsorption; excessive disruption of the penetration barrier in this manner would have become too competitive with initial H2 chemisorption, and thus, discourage overall hydrogen storage.
The scientists also conducted nuclear reaction analysis (NRA) on the 0.3 alloy and the pure Pd. This resulted in findings that the alloy exhibited relatively increased gamma-ray yield near its surface. This emission profile, indicating both H2 chemisorption and adsorption, was 4.5 times greater than that associated with pure Pd.
The NRA analysis, additionally, suggested that the concentration of hydrogen in the first 5 nanometers of the alloy was 13%, compared to 4.2% for Pd. This suggested that the gold in the alloy significantly affected the hydrogen solubility of the underlying Pd.
Some of the Tokyo team’s TDS results also appeared to indicate that the 0.3 alloy also exhibited lower surface temperatures under 100 langmuirs of H exposure. (Source: K. Namba, et al., 2018)
These results validated the effect of sub-monolayer alloying on the performance of Pd as a hydrogen-storage solution. Furthermore, this study has also helped scientists conclude that the effects are related to specific factors, which include differences in penetration-barrier energies and electron-energy profiles.
The research may inform the hydrogen-storage technology of the future, and the role that metals, such as palladium, may take in its applications.
Top Image: Palladium is also a precious metal in its own right. (Source: Money Metals @ flickr)
Why gold-palladium alloys are better than palladium for hydrogen storage, 2018, University of Tokyo News,, (accessed 15 Jul. 18)
K. Namba, et al. (2018) Acceleration of hydrogen absorption by palladium through surface alloying with gold. Proceedings of the National Academy of Sciences.
S. Ogura, et al. (2013) Near-surface accumulation of hydrogen and CO blocking effects on a Pd–Au alloy. The Journal of Physical Chemistry C. 117:(18). pp.9366-9371.
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baby boom
baby boom,
a period in which the birthrate is significantly higher than in other periods, especially the post–World War II period in the United States, Canada, Australia, and New Zealand. In the United States, the postwar baby boom was the largest demographic spike in the nation's history; more than 78 million Americans were born. Experts differ about the span of the U.S. baby boom, which the Census Bureau defines as 1946 to 1964; the number of births peaked in 1957. Some break the period into two sections: "Leading-edge Boomers" (1946–54) and "Generation Jones" (1955–65). Marriage and pregnancy were delayed during the 16 years that spanned the Great DepressionGreat Depression,
..... Click the link for more information.
and World War II. After the war, births went up precipitously as the average ages at which people got married and began having children both went down. The baby-boom years were also marked by an expanding economy, increased educational opportunities, and population shifts to the growing suburbs. The baby boom ended in the late 1960s and by the 1970s America's birthrate had declined to 1930s levels.
Baby boomers are the largest generation in U.S. history, and have had a profound effect on many of the country's political, economic, and cultural trends. Many boomers reached young adulthood during the 1960s and contributed to and were affected by the period's antiauthoritarian and alternative hallmarks, such as political and social activism and rock music. Boomers also are united by such factors as television (they were the first generation to grow up with the medium) and consumerism (they have tended to be voracious commercial consumers). Many baby boomers have struggled to achieve the standard of living enjoyed by their parents because the large size of their cohort has tended to diminish economic opportunity, but the generation as a whole is the richest in American history. In the 21st cent. aging baby boomers are expected to present a significant challenge to the U.S. healthcare industry, MedicareMedicare,
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, and social securitysocial security,
..... Click the link for more information.
See P. C. Light, Baby Boomers (1990), N. A. Hamilton et al., Atlas of the Baby Boom Generation (2000), S. Gillon, Boomer Nation (2004); J. Goldsmith, The Long Baby Boom (2008)
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References in periodicals archive ?
Furthermore, the baby boom generation inpatient costs in Newcastle are greater than the 16-24 age group inpatient costs plus all alcohol-related A&E costs put together.
With 16 million babies born in China in 2009 and the number of births expected to peak in 2015, experts consider this to be the fourth baby boom since 1949.
The authors of the report point out that, "the aging of the baby boom mothers was a one-time event that will not be repeated.
Earth 2 Jane Baby Boom Consumer Decor (tweens' and teens')
The baby boom generation aged and the University did not change its marketing orientation.
Between the miners' strike, the rise of the yuppy and the property crash we managed to find enough time to start a mini baby boom.
Baby boom en el Paraiso/ Hombres en escabeche de Ana Istaru.
On page 32, Glentzer reports on the baby boom at several companies including the Houston Ballet, under the direction of Stanton Welch, who was himself a child of a dancing mother.
As Japan's population continues to age rapidly, the majority of Japan's baby boom seniors will begin shifting towards the 70-and-older group after 2010.
The Baby Boom generation is only now contemplating aging, and gerontologists are beginning to recognize the extraordinary impact their numbers will have on an aging society," says Fernando Torres-Gil, author of The New Aging: Politics and Change in America.
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Whale communication could explain how bushcrickets transfer sound
Ultrasonic bushcrickets could be using a similar method to communicate as that used by whales, according to newly published research.
Dr Fernando Montealegre-Zapata, and his student Fabio Sarria-S from the School of Life Sciences, University of Lincoln, UK, studied the katydids or bushcrickets ultrasonic call frequencies at Gorgona National Natural Park – an extremely humid rainforest located on a Colombian island in the Pacific Ocean.
Katydid species that have extreme ultrasonic frequencies face a problem: ultrasounds travelling in air suffer excess attenuation (weakening) because the wavelength is too short, therefore objects in the dispersive path, such as leaves and branches, interfere and degrade the signal. Sound attenuation is also imposed by environmental conditions such as temperature and humidity. Therefore Dr Montealegre-Z set out to test the hypothesis that the katydids should prefer microhabitats that favour efficient signal transmission.
The team studied 25 species of katydids, which used a variety of song frequencies, ranging between 9 and 150 kHz. It was observed that species with extreme frequencies (>120 kHz) prefer habitats above 12 metres but below the canopy where the vegetation is not cluttered. Ultrasonus (© F. Sarria-S & F. Montealegre-Z), a new genus incorporating three new species with the most extreme ultrasonic signals ever recorded in arthropods, is an example.
Dr Montealegre-Z said: “We think these insects use some kind of environmental channel to broadcast their calls at long distances. For instance, previous research suggests that whales can send a signal from one continent to another because they use the special conditions of the ocean. The ocean offers an amazing ‘channelling’ property that is a function of depth and temperature (sound travels faster at the top and bottom of the ocean, slower in the middle), and salinity. Refraction of waves then causes sound to be trapped in a region of low velocity sound transmission. So, whales can send a signal channelled within this region from one continent to the other in a few hours.
“We think a comparable system occurs in the rainforest, where the call of extreme ultrasonic katydids has a similar effect of being able to travel longer distances through the air at that particular height. Of course the ocean and the air are environments with enormous differences for sound propagation. In the ocean sound travels five times the speed it reaches in air.”
A paper pointing to this hypothesis has been published in the international Journal of Tropical Biology and Conservation.
The typical role of katydids’ singing is to communicate over long distances with the usual calling song produced by males to attract females. But ultrasonic signals are transmitted with difficulty as the distance increases between transmitter and receiver, and the environment conditions are adverse as in a humid rain forest.
This study investigated high frequency signals and space distribution in a vertical stratification.
Dr Montealegre-Z added: “The diversity of insects that produce sound in the tropics challenges our understanding of animal communication mechanisms and their evolution. The use of extremely high frequencies by certain South American katydids suggests unknown acoustic mechanisms responsible for the acoustic energy and the tuning of these signals.
“From this study we can hypothesise that the altitude preferred by these ultrasonic katydids could be situated in an air layer of low-velocity sound transmission optimal for the broadcast of sounds with extreme high frequency. It is possible that at this altitude, with little vegetation and a large acoustic space, environmental types of channels exist to promote the propagation of ultrasonic sounds at long distances.”
Dr Montealegre-Z now plans to measure the acoustic conditions at this level of the rainforest to directly test this hypothesis.
‘Lack of correlation between vertical distribution and carrier frequency, and preference for open spaces in arboreal katydids that use extreme ultrasound, in Gorgona, Colombia (Orthoptera: Tettigoniidae)’ Fernando Montealegre-Z, Fabio A. Sarria, María Cleopatra Pimienta and Andrew C. Mason. Journal of Tropical Biology and Conservation 62 (Suppl. 1): 289-296. http://bioacousticssensorybiology.weebly.com/uploads/1/5/1/2/15122314/montealegre_et_al-arboreal_katydids2014.pdf
Female ultrasonic katydid
Female ultrasonic katydid
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"edu_score": 4.1875,
"fasttext_score": 0.07181203365325928,
"language": "en",
"language_score": 0.9039362668991089,
"url": "https://lifesciences.sites.lincoln.ac.uk/2014/05/19/whale-communication-could-explain-how-bushcrickets-transfer-sound/"
}
|
<p>At the Jozsefvarosi train station in Budapest, Raoul Wallenberg (at right, with hands clasped behind his back) rescues Hungarian Jews from deportation by providing them with protective passes. Budapest, <a href="/narrative/6229/en">Hungary</a>, 1944.</p>
Hungary's capital, Budapest, straddles the banks of the Danube River and is the country's most populous city. Budapest was created by the union of three cities: Buda, Obuda, and Pest.
Swedish protective documentMany Jews searched for places of hiding or for protection. They were aided by Swedish diplomat Raoul Wallenberg and other foreign diplomats who organized false papers and safe houses for them. These actions saved tens of thousands of Jews.
In October 1944, Germany orchestrated a coup and installed a new Hungarian government dominated by the fascist Arrow Cross party. The remaining Jews of Budapest were again in grave danger. The Arrow Cross instituted a reign of terror in Budapest and hundreds of Jews were shot. Jews were also drafted for brutal forced labor.
Death March from Budapest
The Budapest Ghetto
|
<urn:uuid:5879522b-12d1-48cb-b863-f89673ff6a42>
|
{
"dataset": "HuggingFaceTB/dclm-edu",
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"edu_score": 3.796875,
"fasttext_score": 0.1427234411239624,
"language": "en",
"language_score": 0.9766780138015747,
"url": "https://encyclopedia.ushmm.org/content/en/article/budapest"
}
|
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