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Keys to the Past
Pilgrimage of Grace
This was a protest against the Dissolution of the Monasteries in 1536AD. It was led by Robert Aske and had a flag portraying the wounds of Jesus' crucifixion. This sought the restoration of the monasteries - but failed. King Henry VIII went back on his words of sympathy to the rebels and carried out further reforms. Many rebels were killed - these included monks and canons that had joined the rebels under threats and coercion, or as their conscious dictated. Despite the support of the monasteries generally in the rising, the Border area monasteries received little support - the tenants of Tynemouth Priory, the only surviving Northumbrian monastery valued over the £200 level, took the opportunity to chance to rebel against the monastery as their landlord. A further rising was held as the Northern Rebellion for the return of monasteries and Catholic forms of worship.
To explore more glossary entries click on a letter.
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When the United States entered World War I, the Salvation Army was ready. Commander Evangeline Booth (1865-1950) sent a wire to President Woodrow Wilson, placing the personnel of The Salvation Army at his disposal in the United States for any service that it could provide.
The Salvation Army began to organize the War Work Council creating a War Service League. This League functioned in knitting and sewing circles, making sweaters, socks and other personal items. These were distributed through the Red Cross. The Salvation Army War Board began programs in US Army camps and canteens across the country. Many huts and hostels with canteen services were established. Food and beverages were provided for the soldiers, along with books, writing supplies and opportunities for recreation.
The overseas work was also important and received most of the publicity. Officers and men from the American Expeditionary Forces (including General Pershing) were most appreciative of the services provided. The Salvation Army personnel were sent directly to the front line, and moved with the AEF as they moved across France. These Huts were tent-like buildings where the famous doughnuts were created, along with pies, cakes and other home-baked goods.
The soldiers were given a "home away from home" and had the opportunity to sing, read, write letters, and attend church services.
Lt. Colonel Helen Purviance is considered the "first doughnut girl" of The Salvation Army. In 1917, the newly commissioned Ensign Purviance was sent to France. She and other Salvationists would conduct religious services, concerts and baked treats for the "doughboys". Using limited rations and an open stove, Helen and her fellow officers rolled out doughnuts. They rolled the dough using a wine bottle (they were in France !) and fried the dough over the fire. Soon the aroma drew the soldiers to the hut and they lined up, waiting for their turn. Only 150 doughnuts were made that first day; however, once the assembly line was created, up to 9,000 were made daily!
Along the front lines, the doughnuts became the symbol of The Salvation Army's will to bring a touch of home to the soldiers. A small token of sweetness, it has remained in the public's mind for many years as a symbol of warm friendship and service to those in need.
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[ rez-uh-nuhnt ]
/ ˈrɛz ə nənt /
deep and full of resonance: a resonant voice.
pertaining to resonance.
producing resonance; causing amplification or sustention of sound.
pertaining to a system in a state of resonance, especially with respect to sound.
Phonetics. a vowel or a voiced consonant or semivowel that is neither a stop nor an affricate, as, in English, (m, ng, n, l, r, y, w).
Nearby words
1. resolved,
2. resolvent,
3. resolving power,
4. resonance,
5. resonance radiation,
6. resonant cavity,
7. resonant circuit,
8. resonant-jet engine,
9. resonantly,
10. resonate
Origin of resonant
1585–95; < Latin resonant- (stem of resonāns), present participle of resonāre to resound; see -ant
Examples from the Web for resonant
British Dictionary definitions for resonant
/ (ˈrɛzənənt) /
(of sound) resounding or re-echoing
producing or enhancing resonance, as by sympathetic vibration
characterized by resonance
Derived Formsresonantly, adverb
Word Origin and History for resonant
1590s, from Latin resonantem (nominative resonans), present participle of resonare (see resonance).
Online Etymology Dictionary, © 2010 Douglas Harper
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Rahab’s house (Joshua 2)
The Israelite spies instructed Rahab to gather her family into her house, where they would be spared from the coming calamity (Joshua 2:18-19). Later, Rahab and her family members were rescued as promised (Joshua 6:17, 22-23). Joshua 2:15 indicates that Rahab’s house was located within the fortification of Jericho. Translated literally, the Hebrew reads “Her house was against the vertical surface of the city wall, and in the city wall she lived”. How was her house preserved when the wall fell? Remarkably, archaeology provides an answer.
German excavations from 1907-1909 on the northern section of the site uncovered a portion of the lower city wall that did not fall as it did everywhere else. The still-standing section rose as high as nearly 2,5 m, with houses built against it still intact. A second wall at the crest of the embankment revealed that these particular houses were situated between the upper and lower city walls and were thus “in the city wall”. Since the lower wall also formed the back wall of the houses, an opening (window) in the wall would have provided a convenient escape route for the spies. From this northerly location it was only a short distance to the hills of the -judean wilderness, where the spies hid for three days (Joshua 2:16, 22).
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The Edge of Civilization
The first fort built at the Vindolanda site was in about 85 C.E. and was made of wood. Its purpose was to guard the Stanegate Road, a major Roman thoroughfare in northern Britain. The first five forts were wooden. The last two occupations were with stone structures.
The reason so much is known about the occupants is that each time the fort was unoccupied the garrison leaving demolished the buildings so as not to leave ready made fortifications for the enemy. The incoming unit would level the area compacting the ground and prepared the building site with a clay layer.
This process left intact all of the old structure sealed under a clay covering. The earliest fort is buried about four meters deep with each successive occupation easily recognized by the clay layer between the occupations.
The town included all of the people and skills necessary to keep the fort in operating condition. This would have included all the common trades of the day such blacksmiths, stone workers, butchers, bakers, tailors, leather workers, farmers and traders bringing goods from the coast. While it was against the law for soldiers to marry it was commonly overlooked and in a long occupation such as Vindolanda there would be hundreds of soldier families living in the village housing.
Problems within the empire from internal strife, barbarians pushing across the Danube and questions about the need for the protection provided by Hadrian’s Wall, eventually led to calling the troops back to Rome and the abandonment of Vindolanda.
With the troops and the village gone, the remaining inhabitants saw an instant resource in the already quarried and worked stone. Block by block, the walls and timbers found their way into homes, barns and gates. The site rested for nearly 1,300 years until excavations started in the 18th Century and we began to discover the lives of Roman Soldiers on the edge of the empire.
Photo Captions: Vindolanda was occupied off and on for nearly 400 years. In addition to the the Roman garrison a community to support the troops grew up around the fort. Shown is what the latest occupation is believed to look like and current state of the site.
Vindolanda now
Vindolanda as it might have looked
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About Seesaw Sign Up
Students use creative tools in the Seesaw app or website to complete classroom activities like "It's Turkey Time!"
Lorie Felippa
Student Instructions
It's Turkey Time!
How many more feathers does the turkey need to make 10? Draw feathers on each turkey to match the numbers. Draw yellow dots in the tens frame to show how many feathers on each turkey. In a different color show how many more feathers to make 10. Use a label to show how many feathers to make 10.
1st Grade, Kindergarten, Math
1077 teachers like this
Students will edit this template:
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MHA Bell
The History of the MHA Bell
During the early days of mental health treatment, asylums often restrained persons with mental illnesses with iron chains and shackles around their ankles and wrists. Clifford Beers, the founder of the Mental Health Association movement, experienced and witnessed many of these and other abuses. After his own recovery, he became a leading figure in the movement to reform the treatment of, and attitudes toward, mental illness. With better understanding and treatments, cruel practices eventually stopped.
In the early 1950s, in the lobby of the National Headquarters in New York City, the Mental Health Association collected discarded chains and shackles from asylums across the country. All of these restraints were then shipped to the McShane Bell Foundry in Baltimore, Maryland, where they were dropped into a crucible and cast into a 300 pound bell.
The inscription on the bell reads:
“Cast from shackles which bound them,
this bell shall ring out hope for the mentally ill
and victory over mental illness.”
As we seek the vision of victory over mental illness, we need the participation of all citizens in shaping the future of mental health services. We need to remove the shackles from the wisdom of recipients of mental health services and their families and recognize the value of their experience in shaping future policy. Through full citizen participation,
This bell will ring for hope,
This bell will ring for freedom,
This bell will ring for victory.
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Chipewyan, Chipewyan berry-picking party, photograph by Edward S. Curtis.Library of Congress, Washington, D.C.Athabaskan-speaking North American Indians of northern Canada. They originally inhabited a large triangular area with a base along the 1,000-mile-long (1,600 km) Churchill River and an apex some 700 miles (1,100 km) to the north; the land comprises boreal forests divided by stretches of barren ground.
Traditionally organized into many independent bands, the Chipewyan were nomads following the seasonal movement of the caribou. These animals were their chief source of food and of skins for clothing, tents, nets, and lines, although the Chipewyan also relied upon bison, musk oxen, moose, waterfowl, fish, and wild plants for subsistence.
When the Hudson’s Bay Company established a fur-trading post at the mouth of the Churchill River in 1717, the Chipewyan intensified their hunting of fur animals. Members of the tribe also took advantage of their geographic location between the British traders and tribes farther inland, acting as middlemen in the fur exchange by brokering deals with the Yellowknife and Dogrib tribes farther west. Until new trading posts were established in western North America, Chipewyan individuals were able to exact huge profits from this trade. A smallpox epidemic in 1781 decimated the Chipewyan, and subsequent periods of disease and malnutrition further reduced their numbers.
Historically, Chipewyan culture was depicted as rather ruthless. By the mid-20th century such characterizations were generally thought to be inaccurate. Early 21st-century anthropologists characterized traditional Chipewyan culture as one in which individuals typically preferred subtlety to overt action; these anthropologists also described social and individual flexibility (rather than ruthlessness) as important strategies used by the Chipewyan for coping with their difficult northern environment.
Population estimates in the early 21st century indicated more than 1,500 Chipewyan descendants.
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The Struggle for Survival
While Chemical Engineers gained a formal education in 1888, this was certainly no guarantee of success. Many prominent men saw no need for this new profession. Additionally, it was unclear what role chemical engineers would play in industry.
To survive, Chemical Engineers had to claim industrial territory by defining themselves and demonstrating their uniqueness and worth. With this goal in mind, the American Institute of Chemical Engineers (AICHE) was formed in June of 1908. However, just as the chemical engineering profession itself, the Institute faced difficult challenges in defining its territory. The old (since 1876) and powerful (5000 members) American Chemical Society (ACS) had already laid claim to all realms of American Chemistry, both pure and applied.
Just weeks after the formation of AICHE, the ACS would launch its own "Division of Industrial Chemistry & Chemical Engineering" placing itself in direct competition with the AICHE for the hearts and minds of the new engineers. The establishment of chemical engineering in America would certainly involve a fierce struggle for survival.
"Enough already...go to the bottom."
Questions to Ponder
Why did Chemical Engineering not develop in Germany?
What challenges did the newly formed Chemical Engineering Profession face?
Why was the American Institute of Chemical Engineers (AICHE) formed?
How did the AICHE deal with the possible conflict with the ACS?
How has the AICHE helped establish and gain a high status for the chemical engineering profession?
The Story: Establishing the American Chemical Engineer
German Chemical Engineers? "Just say 'Nein'!
With the rapid growth of the American chemical industry around the turn of the century, the gap between laboratory processes and full-scale industrial production needed to be bridged. To many prominent chemists, educated at popular German Universities, the approach to accomplish this had already been tried and proven. Germany had experienced its own rapid period of growth (on their way to becoming the world's greatest chemical power) during the 19th Century. The German solution to industrial scale up involved teaming research chemists and mechanical engineers to take a reaction from the lab bench to the factory floor. They believed this allowed the research chemist to remain creative by not being tied down with the drudgery of engineering practice (whether or not this belief is justified is a whole other topic). Because of this method of scale up the chemical engineer was entirely unneeded, being instead replaced by a chemist and a mechanical engineer.
However, the American chemical industry was fundamentally different from the German industry in several ways. Instead of specializing in fine chemicals or complicated dyestuffs (often made in batch reactors, something all chemists are familiar with), the American industries produced only a few simple but widely used chemicals such as sulfuric acid and alkali (both made in continuous reactors, something chemists have little experience with). These bulk chemicals were produced using straightforward chemistry, but required complex engineering set on vast scales. American chemical reactors were no longer just big pots, instead they involved complex plumbing systems where chemistry and engineering were inseparably rolled together. Because of this, the chemistry and engineering aspects of production could not be as easily divided as they were in Germany. The chemical engineer therefore found a role to play in America despite their absence in the German system (absence until 1960 that is).
Strong Support for an American Chemical Engineer
The American chemical industry (initially following the German example, and why not?) employed chemists and mechanical engineers to perform the functions that would later be the chemical engineer's specialty. However these chemists were of an entirely different nature. The prominent research chemists employed in Germany were almost non-existent in America until after World War I. Instead the American chemical industry employed analytical chemists (involved in materials testing and quality control) and a few production chemists (consisting of plant managers and chemical consultants engaged in engineering design, construction, and troubleshooting). However, unlike the highly praised German research chemists, these American counterparts were given very little respect from the chemical industry which employed them. Employees noted that "analytical chemists were regarded as being of the same grade as machinists, draftsmen, and cooks." This low regard carried over to the weekly paycheck, where in 1905 American analytical chemists received only half the salary of skilled artisans. (R4)
At the turn of the Century, calling yourself a chemist did not bring the immediate admiration of your audience. Instead many of the production chemists (men more closely engaged in management and engineering) wanted very dearly to shed "chemist" from their title altogether. While production chemists were still held in higher regard than their analytical cousins (and also higher paid, funny how that works) they felt great anxiety over the falling status of chemists as a whole. But how to assure that production chemists would keep their high status with manufacturers? This was a problem that could hit them where it would hurt most, the paycheck! The need for action was most imminent! As a solution, the production chemists began referring to themselves as chemical engineers (for this is what they were in practice if not in education), and engaged themselves in the formation of an institute devoted to securing greater recognition for their profession.
An "AICHE Breaky" Beginning
The formation of a society of chemical engineers was originally proposed by George Davis in 1880, a full ten years before the profession could boast of a formal education. (see SETTING THE STAGE ) The first serious proposal for an American Society of Chemical Engineers was presented in a 1905 editorial by Richard K. Meade. He argued that such a society could help secure greater recognition for the chemical engineer, and also help convince the chemical industry that chemical engineers instead of mechanical engineers should be designing and operating their plants. The idea must have rung true, for in 1908 such an organization was formed (however its published goals did not include stealing jobs from mechanical engineers). Hence, the American Institute for Chemical Engineers (AICHE) was born.
In 1908, the year AICHE was formed, the powerful and influential American Chemical Society had been around for 30 years and boasted nearly 5000 members. Additionally, this academic giant had recently committed itself to preventing anymore splinter groups from succeeding from the society. The ACS had been sensitized to the succession problem by the electrochemists and leather chemists who had left the ACS in 1902 and 1904 respectively. Both groups had formed their own independent societies to the dismay of the ACS. So when it seemed that the chemical engineers were also preparing to jump ship (and possible take a lot of applied chemists with them, see Strong Support above) the ACS quickly reacted forming a "Division of Industrial Chemistry and Chemical Engineering."
Avoiding Conflict by "Speaking Softly"
Faced with the possibility of direct conflict with the ACS, the AICHE decided on a course of action designed to minimize rivalry and remain on as good of terms as possible. It accomplished this in three ways:
1) Utilizing very restrictive membership criteria (through 1930) so as not to pose a threat to ACS membership numbers. Part of this exclusive criteria required a full 10 years of industrial experience (5 years if you had a B.S.), thereby excluding most chemists in academia from full membership. This exclusive criteria made membership attractive to those who could gain it, and many compared AICHE membership to belonging to a men's club.
2) Emphasizing a role in which AICHE membership would compliment, not compete with, ACS membership. By requiring industrial experience, the first wave of AICHE members included chemical manufactures, plant management, and consultants (the group formerly called production chemists, see Strong Support above) . This provided a distinct departure from the typical ACS member which was more likely than not to be associated with academia.
3) Finally, AICHE avoided conflict by always approaching possible problems with the utmost discretion. Whether it was membership criteria or the societies political activities, the AICHE always acted in a methodical and conservative fashion. An example of this occurred in 1920, when the Institute considered adding a new class a membership so analytical chemists working in industry could gain membership. However, it was recognized that this action conflicted with a founding principle (not to mention the ACS) that the Institute would cover a professional field not already represented by other societies. As usual, slow sustained growth was recognized as the way to establish the profession while not stepping on too many toes during the process.
The conservative course of action undertaken by AICHE may have slowed membership growth, but it certainly helped bring chemical engineers and chemists into a state of cooperation rather than competition.
How To Define Professional Boundaries?
Another challenge facing chemical engineers involved defining who they were and how they were unique? How the AICHE answered these questions would have tremendous impact on the industrial territory chemical engineers could lay claim to.
Certainly one way the profession would be defined was through the formal education its members received. Because of this the AICHE spent a lot of time and effort evaluating and improving educational activities.
They strove to standardize the chemical engineering education which was erratic and inconsistent. But how exactly to improve education? In an age when chemical engineers learned mountains of industrial chemistry, with each industrial chemical having its own long and varied history of production, what central theme could chemical engineering education rally around?
The answer came in 1915, when in a letter to the President of MIT, Arthur Little stressed the importance of "Unit Operations" (originally utilized instinctually by Davis) in distinguishing chemical engineering from all other professions and giving chemical engineering programs a common focus.
Unit Operations, The "Big Stick" of Chemical Engineering
In transforming matter from inexpensive raw materials to highly desired products, chemical engineers became very familiar with the physical and chemical operations necessary in this metamorphosis. Examples of this include: filtration, drying, distillation, crystallization, grinding, sedimentation, combustion, catalysis, heat exchange, extrusion, coating, and so on. These "unit operations" repeatedly find their way into industrial chemical practice, and became a convenient manner of organizing chemical engineering knowledge. Additionally, the knowledge gained concerning a "unit operation" governing one set of materials can easily be applied to others. Whether one is distilling alcohol for hard liquor or petroleum for gasoline, the underlying principles are the same!
The "unit operations" concept had been latent in the chemical engineering profession ever since George Davis had organized his original 12 lectures around the topic. However, it was Arthur Little who first recognized the potential of using "unit operations" to separate chemical engineering from similar professions. While mechanical engineers focused on machinery, industrial chemists concerned themselves with products, and applied chemists studied individual reactions, no one, before chemical engineering, concentrated upon the processes common to chemical products, reactions, and machinery. The chemical engineer, utilizing the conceptual tool that was unit operations, could now claim industrial territory by proving his uniqueness and worth to the American chemical manufacturers.
Educational Standardization & Accreditation
While the "Unit Operation" concept went a long way in standardizing the chemical engineering curriculum, it did not solve the whole problem. A 1922 AICHE report (headed by Arthur Little, the "originator" of the "Unit Operation" concept) pointed out the continuing need for standardization due to chronic divergence in nomenclature and inconsistencies in course arrangement and worth. Again AICHE took action making chemical engineering the first organization to utilize accreditation in assuring course consistency and quality. AICHE representatives traveled the country evaluating chemical engineering departments. In 1925 these efforts culminated with a list of the first 14 schools to gain accreditation (see EDUCATIONAL GROWTH). Such efforts were so effective in consolidating and improving chemical engineering education that other engineering branches quickly joined the effort (by 1932) forming what would later become the Accreditation Board for Engineering and Technology (ABET).
Summary: Some Details to Remember
People to Remember
(The Dead White Male Guide to History)
Arthur D. Little Consultant and co-founder, with William Walker, of "Little and Walker" which later became "Arthur D. Little, Inc." He coined the term "unit operations" in 1915 and headed up AICHE's Committee on Chemical Engineering Education which emphasized the "unit operation" concept along with accreditation to standardize courses in chemical engineering programs.
Places & Organizations of Interest
AICHE (American Institute of Chemical Engineers)
AICHE is the smallest of the societies representing a "big four" engineering field (mechanical, electrical, civil, and chemical engineering). The Institute was formed in June of 1908 as the sole institutional home for chemical engineers. However, almost before the echoes of McKenna's founding keynote address had finished reverberating, the ACS had launched a new division, joining in a battle for the chemical engineers hearts, minds, and financial dues.
Because of this the institute spent the first third of its life as a very exclusive organization. While it contributed greatly through publications such as "Chemical Engineering Progress" (which provided news and technical information to the entire chemical industry), or through scholastic accreditation, it hardly represented the chemical engineering profession as a whole.
This changed in the 1930's when membership requirements were relaxed, and chemical engineers joined in droves. Today there are five classes of membership (student, affiliate, associate, member, and fellow) through which nearly 60,000 chemical engineers have become members (see AICHE & THE FUTURE). The Institute has a yearly budget of around $21 million, which it spends providing technical education, safety training, career counseling, governmental advising, and social activities for members.
ACS (American Chemical Society)
ACS represents the best American chemistry has to offer. Organized in 1876 (even before chemical engineering existed), the Society grew rapidly. Because of its success, smaller fractions within the society often felt they could go it alone, and splinter groups became a problem. At the turn of the century chemical engineers became one of these splinter groups, forming the AICHE in 1908. The ACS responded by creating the "Division of Industrial Chemistry & Chemical Engineering."
Today the ACS remains at the center of American Chemistry developments boasting 150,000 members. Through its "Chemical Abstracts" service" and "Chemical & Engineering News" the ACS continues to provide valuable information and news to chemists & chemical engineers alike. Despite bitter feelings concerning the creation of the AICHE, today chemical engineers and chemists have a relationship unlike anything found in other engineering fields.
A Brief History Through Quotations
(1880) Sir Harold Hartley said (in 1958, but referring to 1880): "From their experience in chemical plants, both chemists with an instinct for engineering and engineers with a taste for chemistry grew into chemical engineers without realizing it and indeed without being willing to admit it."
(1886) E. K. Muspratt said: "It is very difficult to find a manager who has a knowledge of engineering combined with a knowledge of chemistry. Such men must be educated, and it is only now .. that we are beginning to follow in [this] path." (shows the need for chemical engineers) (F6)
(1888) MIT catalog ("Course X") said in 1888-1889: "This course is arranged to meet the needs of students who desire a general training in mechanical engineering and to devote a portion of their time to the study of the application of chemistry to the arts, especially to those engineering problems which relate to the use and manufacture of chemical products." (chemical engineering education begins) (V1)
(1904) George Davis (in his "Handbook of Chemical Engineering) said: "The object of this handbook is not to enable anyone to erect works of special character ... but to illustrate the principles by which a plant of any kind may be designed and erected when certain conditions and requirements are known. We cannot make the best use of our abilities unless we are taught to investigate the principles underlying the construction of the appliances with which we have to work." (early recognition of the need to understand underlying physical and chemical principles in chemical engineering) (D1).
(1904) Hugo Schweitzer (at an ACS meeting) said: "I am absolutely against the introduction of chemical engineering in the education of chemists." (not everyone was excited about chemical engineering)
(1908) Charles McKenna (founder of AICHE referring to that founding) stated: "..the noblest aim before us, gentlemen, the one which most amply justifies us before all the world, is our ambition for the enlightenment and ample equipment of our successors: that is for the improvement of the training of the chemical engineer of the future." (education was important to AICHE from the start) (R3)
(1910) F. W. Atkinson (Brooklyn Polytechnic Institute) said: "Chemical engineering needs to be more sharply defined. Its scope is still in a somewhat indeterminate state and as yet its position as one of the professions is not clearly recognized." (defining what chemical engineers were and what made them unique was an early problem) (R3)
(1911) Milton C. Whitaker (professor at Columbia University, stating his ideas of what chemical engineering education should consists of) said: "The chemical engineer works in the organization, operation and management of existing or proposed processes with a view to building up a successful manufacturing industry... His fundamental training in chemistry, physics, mathematics, etc., must be thorough and must be combined with a natural engineering inclination and an acquired knowledge of engineering methods and appliances." (Sounds pretty modern doesn't it?) (P2)
(1911) Olaf Hougen (an eminent professor at the University of Wisconsin, revealing that the actual teaching practices of the past were different indeed) said in 1972: "The 1911 curriculum in chemical engineering ... bares no resemblance to that of today. ... there were: no courses in unit operation, none in material and energy balances, none in heat and mass transfer, none in thermodynamics for chemical engineers, none in chemical kinetics and catalysis, none in process design, none in process control ... and, physical chemistry was not a required course." (OK, so maybe their education wasn't so modern.) (H7)
(1915) Arthur D. Little (consultant responsible for bringing "unit operations" into the lime light) said: "Any chemical process, on whatever scale conducted, may be resolved into a coordinate series of what may be termed "Unit Operations, as pulverizing, dyeing, roasting, crystallizing, filtering, evaporation, electrolyzing, and so on. The number of these basic unit operations is not large and relatively few of them are involved in any particular process. The complexity of chemical engineering results from the variety of conditions as to temperature, pressure, etc., under which the unit operations must be carried out in different processes, and from the limitations as to material of construction and design of apparatus imposed by the physical and chemical character of the reacting substances." (unit operations, the rallying point of chemical engineering for 30 years) (R3)
(1921) H. O. Chute (a chemical engineer specializing in distillations and holding over a dozen patents) said: "We are not even able to convince other engineers that we are engineers." (the unit operations concept was slow to take hold and did not solve all the problems) (R3)
(1922) A "monumental" AICHE report on education conducted by Arthur Little declared: "Chemical engineering..., as distinguished from the aggregate number of subjects comprised in courses of that name, is not a composite of chemistry and mechanical and civil engineering, but a science of itself, the basis of which is those unit operations which in their proper sequence and coordination constitute a chemical process as conducted on the industrial scale." (The heart of this report involved recommendations to stress the "Unit Operation" concept, standardize university programs, and begin university accreditation.) (R3)
(1922) Ralph McKee (AICHE director 1923-25) said: "The Committee have written a prescription, and it is our duty to see that the prescription is filled .. and given to the patients..." (AICHE takes action) (R3)
(1928) Alfred Holmes White (AICHE president 1929-30) said: "Almost all schools which teach chemical engineering now recognize these unit processes (i.e. unit operations) as providing the framework for the engineering side of chemical engineering." (unit operations a continued rallying point for standardization) (R3)
(1932) J. V. N. Dorr (AICHE president from 1932-33) said: "The four founder societies while tending originally to regard us as 'queer kinds of chemists' now recognize us as a fifth classification of basic engineering." ("Fifth" referring to Civil, Mechanical, Electrical, Mining, and of course Chemical engineering). (It was working, the profession was becoming established) (R3)
Quotations from the University of Minnesota
(Don't take all of these too seriously!)
(1993) Rutherford Aris (or is it Aris Rutherford, sometimes it is hard to tell "Who's Who") (Chemical Engineering Professor at the University of Minnesota) said: " is easy to accept mathematical modeling as a poetic activity, for, in doing it, we are engaged in a form of imitating nature in mathematical terms." (A2)
(1995) Cussler said: "The score is kept in dollars!"
(1995) Lanny Schmidt said: "You can count the number of ... [insert your favorite phrase here] .... on the fingers of one hand of an explosives expert."
(1995) The University of Minnesota student bulletin said: "The chemical engineer is primarily a producer whose special province is to develop a process from its laboratory beginnings through ... to full-scale production. Chemical engineering is based on applications of chemistry, physics, mathematics, economics, and increasingly, biology and biochemistry. Because of this broad-based foundation .. the chemical engineer is considered the universal engineer. ... Chemical engineering deals with unit operations... These operations are vital to the commercial success of industries based on chemical or physical transformation of matter. A chemist uses these operations qualitatively in a laboratory, but to apply them to a complex or large-scale industrial process requires a chemical engineer who has a complete and quantitative understanding of the engineering principles as well as the scientific principles on which the operations rest. ... Because many industries are based on some chemical or physical transformation of matter, the chemical engineer is much in demand." (I1)
more quotations to come...
Table of Contents
Setting the Stage (1888)
A Century of Contributions
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[kuh-luhm-ner] /kəˈlʌm nər/
shaped like a .
characterized by :
columnar architecture.
Also, columnal. printed, arranged, etc., in :
data in columnar form.
1728, from Late Latin columnaris “rising in the form of a pillar,” from columna “column” (see column).
Read Also:
• Columnar-epithelium
noun, Biology. 1. epithelium consisting of one or more layers of elongated cells of cylindrical or prismatic shape. columnar epithelium n. Epithelium made up of cells that are taller than they are wide and that form a single layer.
• Columnar cell
columnar cell co·lum·nar cell (kə-lŭm’nər) n. A cell, usually epithelial, that is tall, narrow, and somewhat cylindrical.
• Columnarized
[kuh-luhm-nuh-rahyzd] /kəˈlʌm nəˌraɪzd/ adjective 1. (def 3).
• Columnar-jointing
noun 1. (in basaltic igneous rocks) a series of generally hexagonal columns formed by vertical joints as a result of contraction during cooling.
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"url": "http://definithing.com/define-dictionary/columnar/"
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Dignāga, (born c. 480 ce—died c. 540), Buddhist logician and author of the Pramāṇasamuccaya (“Compendium of the Means of True Knowledge”), a work that laid the foundations of Buddhist logic. Dignāga gave a new definition of “perception”: knowledge that is free from all conceptual constructions, including name and class concepts. In effect he regarded only pure sensation as perception. In his theory of inference he distinguished between inference for oneself and inference for the other and laid down three criteria of a valid middle term (hetu)—i.e., that it should “cover” the minor premise (pakṣa), be present in the similar instances (sapakṣa), and be absent in dissimilar instances (vipakṣa). In his Hetucakra (“The Wheel of ‘Reason’”), Dignāga set up a matrix of nine types of middle terms, of which two yield valid conclusions, two contradictory, and the rest uncertain conclusions. Dignāga’s tradition was further developed in the 7th century by Dharmakīrti.
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"url": "http://www.britannica.com/print/topic/163392"
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Cheliceramorpha: Life History and Ecology
Chelicerates occupy a variety of roles in the ecology of marine systems and on land as well. The above picture from the Smithsonian shows a spider upon its web. While many spiders build webs, others do not, but instead ambush prey as it passes by. This is also the tactic used by scorpions, another group of chelicerate predators. The predatory habits of these critters helps to control insect populations in many parts of the world.
Some arachnid chelicerates are parasites, such as ticks and mites. They live upon the bodies of other animals and feed on the blood, skin, or hair. Some of these carry diseases, which they pass on to the host when they feed. Still other chelicerates are tiny organisms which feed on detritus, the bits of decaying matter that accumulate on and below the ground. The first terrestrial chelicerates are believed to have been detritus feeders.
Parental care is not common among the chelicerates, but some scorpions will carry their young on their backs for a time. In most cases, however, no such care is provided, and the young must fend for themselves from the time they hatch. Survival is then dependant on the fact that large numbers of eggs are produced at a time, and it is likely that at least a few will survive.
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"language_score": 0.9632982015609741,
"url": "http://www.ucmp.berkeley.edu/arthropoda/chelicerata/cheliceralh.html"
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mensural notation
A system of notation established around 1260, remaining in use until about 1600. Initially, the three principal note values in use were the long, breve, and semibreve. The long was equal to three breves, and the breve equal to three semibreves. An additional fourth note, duplex long, was equal to two longs. By the 14th century, the minim was added and by the 15th century, the semiminima and fusa were also added.
In Mensural Notation, several notes can be combined together to form ligatures. In a ligature, the relationship between any two adjacent notes can be either triple (3) or duple (2). The relationship between the long and breve is the modus, and if the modus is triple (three breves to the long), then it is major. A duple modus (two breves to the long), is said to be minor. Similarly, the relationship between the breve and semibreve is the tempus, and if the tempus is triple (three semibreves to the breve), then it is perfect. A duple tempus (two semibreves to the breve), is said to be imperfect. Finally, the relationship between the semibreve and minim is the prolatio, and if the prolatio is triple (three minims to the semibreve), then it is major. A duple prolatio (two minims to the semibreve), is said to be minor.
See the table of mensural notation symbols in the Appendix.
Last Updated: 2013-05-06 15:46:26
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"language_score": 0.9526397585868835,
"url": "http://dictionary.onmusic.org/terms/2145-mensural_notation"
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From Wikipedia, the free encyclopedia
Jump to: navigation, search
Also called Quinquatrus
Observed by Roman Republic,
Roman Empire
Type Classical Roman religion
Date 19 March
In ancient Roman religion, the Quinquatria or Quinquatrus was a festival sacred to Minerva, celebrated on the 19 March. According to Varro,[1] it was so-called because it was held on the fifth (quinqu-) day after the Ides, in the same way as the Tusculans called a festival on the sixth day after the Ides Sexatrus or one on the seventh Septimatrus.[2] Both Varro and Festus state that the Quinquatrus was celebrated for only one day, but Ovid[3] says that it was celebrated for five days, hence the name: on the first day no blood was shed, but that on the last four there were contests of gladiators. The first day was the festival proper, and that the following four were an expansion made perhaps in the time of Caesar to gratify the people. The ancient Roman religious calendars assign only one day to the festival.
Ovid says that this festival was celebrated in commemoration of the birthday of Minerva; but according to Festus it was sacred to Minerva because her temple on the Aventine was consecrated on that day. On the fifth day of the festival, according to Ovid,[4] the trumpets used in sacred rites were purified; but this seems to have been originally a separate festival called Tubilustrium, which ancient calendars place on 23 March. When the celebration of Quinquatrus was extended to five days, the Tubilustrium would have fallen on the last day of that festival.
As this festival was sacred to Minerva, it seems that women were accustomed to consult fortune-tellers and diviners upon this day.[clarification needed] Domitian caused it to be celebrated every year in his Alban villa, situated at the foot of the Alban hills, and instituted a collegium to superintend the celebration, which consisted of shows of wild beasts, of the exhibition of plays, and of contests of orators and poets.[5]
There was also another festival of this name called Quinquatrus Minusculae or Quinquatrus Minores, celebrated on the Ides of June, on which the tibicines went through the city in procession to the temple of Minerva.
Historical significance[edit]
At the Quinquatria in 59, Nero invited his mother, Agrippina the Younger, to his villa near Baiae, in an attempt to assassinate her. His old tutor, Anicetus, whom he had raised to be captain of the fleet of Misenum, had undertaken to construct a vessel which could be sunk, without exciting suspicion. Agrippina landed at Bauli, between Baiae and Cape Misenum, and completed her journey in a litter. After the banquet, when night had fallen, she was induced to return to Bauli in the vessel which had been prepared for her destruction. But the mechanism did not work as planned, and Agrippina succeeded in swimming to shore, from which she proceeded to her villa on the Lucrine lake. Nero soon after succeeded in his goal, however, with further help from Anicetus.[6]
1. ^ de Ling. Lat. vi.14
2. ^ In similar fashion, Festus states that the Faliscans called a festival on the tenth day after the Ides Decimatrus.
3. ^ Fasti iii.809, &c.
4. ^ Fasti iii.849
5. ^ Suetonius, The Life of Domitian, 4
6. ^ Bury, p 279.
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"language_score": 0.9733232259750366,
"url": "http://en.wikipedia.org/wiki/Quinquatria"
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A measure of the tendency of a gas to escape or expand. Fugacity is the pressure required at a given temperature to make a non-ideal gas behave as an ideal gas (same Volume, Free Energy, etc.) In thermodynamics, this "effective pressure" is used in place of the real pressure to calculate phase equilibria and changes in energy. Becasue of this use, the fugacity is often written as a product of the pressure with the fugacity coefficient (γ):
Fu*gac"i*ty (?), a. [L fugacitas: cf. F. fugacit'e.]
The quality of being fugacious; fugaclousness; volatility; as, fugacity of spirits.
Uncertainty; instability.
© Webster 1913.
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"language": "en",
"language_score": 0.884122371673584,
"url": "http://everything2.com/title/Fugacity"
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How to Use the Images
Inquiry Question
Historical Context
Drawing 2
Photo 1
Photo 2
Photo 3
Table of
Visual Evidence
Drawing 1: Delaware Avenue, Buffalo,
New York, 1873.
[Drawing 1] with link to larger version of photo.
(National Park Service)
The house where Roosevelt became our 26th President, known today as Theodore Roosevelt Inaugural National Historic Site, was constructed in 1839 as part of a United States Army Barracks at the northern boundary of Buffalo. Strained relations between the United States and Great Britain during this period and political unrest in Canada during the Upper Canada Rebellion caused alarmed citizens to petition the government to build a military post in Buffalo. The commanding officer and post surgeon occupied the house, which was described as "a substantial building, with a portico and large columns."¹ When the Army abandoned the barracks in the 1840s, the house passed into private ownership. In 1884, Buffalo lawyer Ansley Wilcox and his family took up residence there. By that time Delaware Avenue had become the most fashionable street in the city. Elegant mansions lined both sides of the avenue while stately elm trees formed a canopy over it.
Questions for Drawing 1
1. Why did Buffalo citizens want to have a military post in the area?
2. What happened to the house after the Army left the area?
3. Based on the short quote above, try to locate the Theodore Roosevelt Inaugural National Historic Site on the left side of Delaware Avenue. What features may have made this a popular area for wealthy families to live?
4. What evidence can you find in the drawing of Buffalo's growth as an industrial city?
Comments or Questions
National Park Service arrowhead with link to NPS website.
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"url": "http://www.cr.nps.gov/nr/twhp/wwwlps/lessons/77troosevelt/77visual1.htm"
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Military Administration (Nazi Germany)
From Wikipedia, the free encyclopedia
Jump to: navigation, search
During World War II, Nazi Germany created military-led regimes in occupied territories which were known as a Military Administration (Militärverwaltung). These differed from Reichskommissariats which were led by Nazi Party officials. A Military Administration was led by a "Military Commander" (Militärbefehlshaber, official acronym MilBfh.).
The various Military Administrations created by Nazi Germany were:
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"fasttext_score": 0.10540759563446045,
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"language_score": 0.9567059874534607,
"url": "http://en.wikipedia.org/wiki/Military_Administration_(Nazi_Germany)"
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From Wikipedia, the free encyclopedia
Jump to: navigation, search
Bacteriophages are similar to viruses that infect eukaryotes (plants, animals, and fungi) in that there are many different kinds of structures and functions. Bacteriophages are typically made of an outer protein hull that has genetic material inside it. The genetic material can be ssRNA, dsRNA, ssDNA, or double-stranded DNA between 5 and 500 kilo base pairs long with either circular or linear arrangement. Bacteriophages are usually between 20 and 200 nanometers in size.
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"fasttext_score": 0.5916043519973755,
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"language_score": 0.9267086982727051,
"url": "https://simple.wikipedia.org/wiki/Bacteriophage"
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• To demonstrate changes in air pressure.
• Straight pins
• 1 inch by 1 inch piece of cardboard
• Wooden spool
• Stick the pin through the piece of cardboard and push the pin through the hole of the spool.
• Hold the cardboard against the spool.
• Blow through the opposite end of the spool and let go of the piece of cardboard.
wooden spool on cardboard
• Blowing into the spool makes the cardboard cling to the spool.
• Why does the cardboard cling to the spool when you blow on it? (The pressure in the air flowing through the hole in the spool and up to the cardboard becomes lower, the pressure on the other side of the cardboard is greater than that inside the hole, therefore, the cardboard clings to the spool.)
• If you blow real hard, the cardboard clings even tighter. Why? (Because the outside pressure is stronger than your breath inside the hole.)
• Atmospheric pressure on the bottom of the cardboard is stronger than the pressure inside the spool and holds the cardboard.
Note that this is an application of Bernoulli�s Principle.
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"edu_score": 4.03125,
"fasttext_score": 0.1588953137397766,
"language": "en",
"language_score": 0.8805661797523499,
"url": "https://www.faa.gov/education/educator_resources/educators_corner/grades_7_8/air_has_pressure/"
}
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Phase-shift keying
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Phase shift keying is a way of transmitting information. This is done by modulating the phase of a carrier wave. In such a system, the amplitude of the wave does not carry any information; all information is present in the phase of the signal. In many cases, this allows to better use the bandwidth available.
The Gray code for Binary-phase-shift keying (2PSK)
If we think of a wave as a wiggly line, (like a sine wave), wiggling a specific amount of times a second, and we can change at which part of the wiggle it is in. Say if it is at the top of its wiggle, and we immediately change it to the bottom of its wiggle, this is called a phase shift. We can use that change to carry information.
By either changing or not changing the wave every time it gets to the top of its wiggle, we can send either ones or zeros. This is called Binary Phase Shift Keying. If we change the phase of the wave as it reaches the top, we can have this represent a 1. If we don't change it at the top, we can have this represent a 0. We can use a computer and a radio to turn text into a wave like this and then send it. A radio and a computer listening to this wave changing or not changing can figure out the original message being sent and turn it back into text.
Binary Phase Shift Keying can be used to send computer data across radio waves quite efficiently. Certain Wireless LAN standards use Phase-shift keying, which they sometimes couple with Orthogonal frequency-division multiplexing, to get higher data rates.
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"language_score": 0.9257221221923828,
"url": "http://simple.wikipedia.org/wiki/Phase-shift_keying"
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From Wikipedia, the free encyclopedia - View original article
Jump to: navigation, search
Oilcloth was, traditionally, close-woven cotton duck or linen cloth with a coating of boiled linseed oil to make it waterproof. Historically, pre-Macintosh, oilcloth was one of very few flexible, waterproof materials that was widely available. Leather was expensive, very expensive in large pieces, and required regular maintenance if often wetted. Oilcloth was used as an outer waterproof layer for luggage, both wooden trunks[1] and flexible satchels, for carriages and for weatherproof clothing.[2]
Boiled linseed oil was prepared by a long boiling of linseed oil with metal salts, originally lead dross.[2] The modern oil is less toxic, but also less suitable for making oilcloth. Re-enactors may boil their own oil in the search for a correctly coloured oilcloth.[2][3] Oilcloth used for weatherproofing may have used a mixture of lead and manganese salts, the sienna and umber pigments, to give a more humidity-resistant cure.[2]
The fabric was first stretched on a tenter frame and sized with animal gelatine. The oil was then applied and allowed to cure between coats. As the cure relies on oxidation by the air, thin coats and long cure times between are required. [2][3]
Overlaps between sheets of fresh oilcloth would amalgamate naturally when pressed together. This tendency also led to the cloth sticking together when folded. Where a folding cover was needed, the cloth was waxed or dusted with pumice to reduce this.
Seams in traditional oilcloth could be coated after sewing to reduce leakage through their stitching. This was generally unsatisfactory for clothing though and so overcoats of this era would incorporate one or more short capes over the shoulders. These capes were made in one piece and covered the inevitable shoulder seams in the main garment. These capes remain today in garments such as the Ulster and Inverness.
In the 19th century, waxed cotton developed and began to gradually replace oilcloth, especially for clothing.
In the mid 20th century the term "oilcloth" was often used as a misnomer for linoleum.[citation needed]
The most familiar recent use was for brightly printed kitchen tablecloths. Dull-colored oilcloth was used for bedrolls, sou'westers, and tents. By the late 1950s, oilcloth became a synonym for vinyl (polyvinyl chloride) bonded to either a flanneled cloth or a printed vinyl with a synthetic non-woven backing.
See also[edit]
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"language_score": 0.9686616063117981,
"url": "http://blekko.com/wiki/Oilcloth?source=672620ff"
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|
Skip to main content
BFI logo
Screenonline banner
Protect and Survive (1976)
Each episode starts with an animated atomic mushroom cloud followed by a reminder of the main points from the previous episode. Step-by-step instructions on how to improve one's chances of survival during a nuclear attack are illustrated using simple animation and still photography. The family home is represented by a cardboard model resembling a doll's house and warning sirens and fall-out dust are visually represented by vibrating lines and white snow respectively. Each of the twenty-two episodes deals with a particular aspect of survival.
1. Nuclear Explosions Explained
2. The Warnings
3. What to do When the Warning Sounds
4. Stay at Home
5. Choosing a Fall-out Room
6. Refuges
7. Materials to Use for Your Fall-out Room and Refuge
8. Make Your Fall-Out Room and Refuge
9. What to Put in Your Fall-out Room
10. Action After Warnings
11. Water and Food
12. Sanitation - Preparatory Steps
13. Fire Precautions
14. The Importance of Your Radio
15. Life Under Fall-out conditions
16. What to do After an Attack
17. Sanitation Care
18. Water Consumption
19. Food Consumption
20. Casualties
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"fasttext_score": 0.05420124530792236,
"language": "en",
"language_score": 0.8331247568130493,
"url": "http://www.screenonline.org.uk/film/id/724975/synopsis.html"
}
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V. Imperfect Vowel Stem
1. Imperfects in -e, -a appear usually in pure stems with athematic inflection or adding an -u in every form, which is normally an Past ending at least for some persons. Other endings can also be added to this stems.
NOTE. -u is rare in the Present and frequent in the Imperfect, and the contrary has to be said of -i.
Opposed to the Present, the stem in -e or -a is often a Past stem.
2. The basics of the Imperfect vowel stems are thus the opposition to Presents:
a. Present -i (thematic or semithematic), Imperfect -e; as, mnio / mne, be mad.
b. Present -i, Imperfect -a; as, alkio / alka, be hungry.
c. Present -e/-o, Imperfect -e; as, lege / lege, collect, speak.
d. Present -e/-o, Imperfect -a; as, gnte / gntau,know.
3. The use of the forms in -u is usually related to the Past (and sometimes the Perfect), as a suffix or ending. It can be -u, -au, -eu, -eue, -aua, -eua, -aue.
4. The -i/-i is scarcely used for Past stems; as, audhio / audhiui, hear. The stem is sometimes lengthened in -e/-i, often to help avoid the loss of consonants in the Imperfect in -s.
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"language": "en",
"language_score": 0.8938815593719482,
"url": "http://dnghu.org/en/grammar/noskin2/imperfect_vowel_stem.htm"
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Identifying Anions
In this anions worksheet, students are given a table showing 9 anions, the test that indicates the presence of each anion and what will be observed when each substance is added to the anion.
9th - 12th Science 5 Views 5 Downloads
Resource Details
1 more...
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What Members Say
Christine K.
Christine K., secondscience
Sylvania, OH
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The Cowlitz Indian Tribe
The name Cowlitz Tribe refers to two Northwest Native American groups, the Lower and Upper Cowlitz, and the river drainage that was their aboriginal home. Positioned in the interior southwest of today's Washington State, the tribes' original territory comprised some 3,750 square miles. By some accounts, the name Cowlitz means "spiritual seeker."
The more numerous Lower Cowlitz inhabited 30 villages along the Cowlitz River, about a mile from the Columbia River northward to the present-day town of Mossyrock. The Upper Cowlitz lived in villages east of Mossyrock, then camped during warm weather at loftier elevations of the Cascade Crest, then along the Tieton River several miles east of the crest.
In winter, the Cowlitz lived near fish-laden streams in sturdy cedar longhouses. Storytelling and ceremonies enlivened their cold-weather evenings. The performance of dance and song sought to ensure availability of food and to avoid evil.
In the spring, families moved to the prairies to dig up wapato (Indian potato) and camas bulbs, which provided starch for their diet. They trekked to the mountains to harvest game and berries. In addition to its food-gathering function, camping provided a setting for social interaction.
Upon reaching adolescence, Cowlitz youths departed on fasting quests to seek visions of a spirit guide to help them become productive members of the tribe. Owing to their insular location, the Cowlitz were more tightly knit than other Salish-speaking bands on the Columbia River and the coast. Nevertheless, the Cowlitz pursued trade and relations with neighboring tribes. They traveled on trail and river routes to contact their neighbors. On the rivers they used snub-nosed canoes capable of negotiating rapids. Barter items included slaves, horses, various plant and meat foodstuffs, pelts, hides and baskets. They also exchanged items through gaming, horse racing and powwows.
The earliest historical accounts of the Cowlitz began in 1811 with the arrival of Pacific Fur Company agents out of Astoria. The second engagement between the Cowlitz and non-Indians took place after the North West Company, which had bought out the Pacific Fur Company in 1813, dispatched hunters and trappers — including Iroquois Indians — up the Cowlitz River. This opening into Cowlitz country provided the Hudson Bay Company, which merged with the North West Company, a chance to trade with the natives.
An epidemic in 1829 and 1830, believed to be a virulent Asian influenza, was carried in by Captain John Domines' American ship Owyhee. Affected villages became hellish scenes of sickness and death, and populations dropped precipitously.
In the mid-19th century, native and non-native relations grew episodically ugly as pioneers, backed by the U.S. government, began to set roots on Cowlitz lands. The principal aims of Cowlitz chiefs were to establish cooperation with the federal government and a permanent Cowlitz territory. Two treaties were negotiated in the middle 1800s. The Congress failed to ratify the first one. In 1855, during a second treaty session with territorial governor Isaac Stevens, the Cowlitz refused to become parties to a document that would eliminate their rights to traditional homelands, then relegate them to the alien coastal Quinault reservation. The treaty collapse led to the United States government's confiscation of territory and resources without the Cowlitz' assent.
When war between the Indians and whites erupted that same year, the Cowlitz tribe was assured they would be provided with a reservation if their agitated young braves did not join in the fighting. As a result, the Cowlitz area remained free of native-initiated violence during the war. However, the assurance of a Cowlitz reservation in return for cooperation was evidently ignored.
In 1906, a Cowlitz chief named Atwin Stockum sued the federal government to retrieve several pieces of land for his tribe, thus inspiring a series of disputes with the government over decades. Throughout the 1900s, the Cowlitz Tribe carried on a lonely defense of its interests.
Also at the beginning of the 20th century, the system of chiefs evolved into a system of elected presidents. In addition, by 1950, a constitutional elective tribal council structure came into being.
The State of Washington commenced to enforce its fish and wildlife regulations against Indians in 1920, provoking confrontations between enforcers and the Cowlitz. The long-term struggle was finally resolved with the issuance of ID cards to the Cowlitz, which entitled bearers to fish and hunt for subsistence.
In the 1950s, the Cowlitz tried to dissuade the City of Tacoma from building a hydroelectric dam on the Cowlitz River near the site of Taoup, an old Cowlitz village. The city prevailed and dam backwaters inundated individual holdings and tribal burial grounds.
In 1946, the Cowlitz land-claims efforts shifted from dealing with the Congress to the new Indian Claims Commission set up by the United States. In 1951, the Cowlitz leaders entered a land-claims petition against the federal government. Twenty-two years later, the commission found in favor of the Cowlitz Indian Tribe by asserting that the government had in effect deprived the tribe "...of its aboriginal Indian title as of March 20, 1863, without payment of any compensation therefore." The commission further acknowledged a total area of 1.66 million acres, about two-thirds of the aboriginal land area. The settlement put forth by the United States came to about a half dollar an acre.
Throughout the last two decades of the century, the Cowlitz pressed their efforts to win formal recognition from the federal government.
See Indian Wars Time Table .
Native American Cultural Regions map .
Off-site search results for "The Cowlitz Indian Tribe"...
The Narragansett Indian Tribe
But the Narragansett were completely defeated.After the war, the remaining Narragansetts were forced to live on reservation lands, but by the end of the 18th century, the reservation lands had been drastically reduced. The state of Rhode Island ...
Delaware Indian - Is the Delaware Indian tribe, a Federally recognized tribe?
... recognized tribe? The Delaware Indian tribe is the same as the Lenape Indian tribe. If you are asking about their Federal recognition, it is true that some of the various Delaware tribes are not yet Federally recognized. Home ...
American Indians - The North American Indian Tribes
... The Kato, The Maidu, The Miwok, The Pomo, The Wailiki, The Wintun, The Yokuts, The Yuki Cahuilla, Dieguenos, The Luisenos, The Mono, The Pavioso, The Washo The Tiwa (Isleta, Taos),The Keres (Cochiti, Santa Domingo, Acoma, Laguna, Sia, and ...
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Current time:0:00Total duration:9:18
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Learn the difference between Arteriosclerosis, Arteriolosclerosis, and Atherosclerosis! Rishi is a pediatric infectious disease physician and works at Khan Academy. Created by Rishi Desai.
Video transcript
So there are a few words that get thrown around, and when I was going through and learning them, I was always confused. And so I thought I'd go and talk about them right now. The first word is arteriosclerosis. And I'm going to underline the one "o" here. And very similar to this word, there's the word arteriolosclerosis, with an extra "l" and "o", and everything else is the same. The first thing I always wondered was, are these the same word that someone just misspelled? But actually that's not the case. This is two separate words for two separate things. And the third word is atherosclerosis. I always used to wonder the same thing about this word. It was just like, is this just another way to spell it? Maybe the British spelling or something like that? But actually it's another word that's different in meaning as well. So these three words often get confused for one another. And sometimes you'll even see that they are referred to as the same thing. But there are some subtle differences that I want to talk about. So let's start with the first two words arterio- and arteriolosclerosis. And these basically get to the question, answering the question, of What? What is happening? And the process of arteriosclerosis and arteriolosclerosis is that you basically have stiffening of blood vessels. So if you have, let's say, a normal vessel-- I'll draw it in red-- like a little rubber hose, this is a very soft, flexible vessel. And over time, if it becomes stiff, like a lead pipe, then you have something like this, a very firm vessel. So the same size, but basically the walls are becoming very, very stiff. And arteriolosclerosis is kind of the same process. And so, so far I have not convinced you that there's any difference, right? Same basic process. So you're probably left wondering, well, then what is the difference? I'm going to firm. Well, the difference is that arteriosclerosis is happening in the large arteries and middle sized arteries. And remember we divided up the arteries into large and middle. And on the other side, we said, what about the small arteries and arterials? And that's over here. So basically, if this process is happening in the large or middle arteries, we would call it arteriosclerosis with a single "o." But if it's happening in the small arteries and arterials, we would call the same process arteriolosclerosis. So that's the key difference, right? Where is it happening? Now in terms of answering the question of what, this is the process. But you have to ask yourself, why does that matter? Why does it matter if something's going from soft to firm? Now, I'm going to draw a little spectrum for you, and on this side, we have the word "not," and here you have "very." And these are referring to compliance. So try to remember back to what we said about compliance. And that's whether or not a vessel can stretch, almost like stretchability. And if you think about what would be very stretchable, or very compliant, we've got veins. So that would be over here, a vein. Very compliant, right? And arteries are over here. They're not so compliant. They're not completely stiff, but compared to veins, they're not very compliant. So they have a much lower compliance than veins. And a lead pipe would be right here, basically right next to "not." This would be a lead pipe, right? And so when we talk about arteriosclerosis or arteriolosclerosis as something that's soft going into something that's firm, we're really talking about the artery moving from where it is on the compliance spectrum over here, towards not too compliant at all. So really we're talking about losing compliance. Let me write that-- losing compliance. That's really important. And that's really what we're talking about. Losing compliance. Now, how do we get to a point where we're losing compliance? How does that happen, exactly? Well, that's another question. That's the question of how, how does this happen? And there we can talk about atherosclerosis. So atherosclerosis is a process, and that-- I can even draw it out for you very quickly. This is, let's say, a blood vessel, an artery. And I'll draw two layers for its wall, although we know that there's actually three layers. Just to make it simple. I'm just drawing two layers just to show you there's a thickness. And let's say that you have some fat deposit here, and maybe one over here. And over time, we know that this is going to cause some blockage of the vessel. But also, in addition to losing space in the lumen-- this is the lumen-- in addition to losing space in the lumen, you also have some calcification, and some fibrous tissue starts kind of laying down here. So this wall, instead of being nice and soft and red, I'm going to draw it as very firm and white. Very firm. So this part of the wall, and maybe even this part of the wall, become very non-compliant. They lose compliance here. So these parts of the walls are very firm. They're not going to stretch out very easily. So that's atherosclerosis. And the reason I listed it under this section-- here, if I can divide it in half-- is that most often, not always, but most often, atherosclerosis is happening in the larger or middle sized arteries. It doesn't happen as often in the small arteries and arterials. So it's happening more often in the large and middle arteries, and so it's going to cause arteriosclerosis. So atherosclerosis is the "how," and arteriosclerosis is the "what" for the large and middle sized arteries. Now let's shift over to the small arteries and arterials. So, if I just told you that atherosclerosis doesn't happen too often in the small arteries, well then, how in the world does arteriolosclerosis happen? Again, arteriolo, with an "olo." How does that happen? OK. Let me write out for you a couple words. These are words that you might come across-- hyaline and hyperplastic. So, these are just names for a process. So these are, again, these are answering the question of "how" does arteriolosclerosis happen? Well, it happens through hyaline or hyperplastic arteriolosclerosis, so the word appears again here. And this-- let me just draw it for you like I did before. We have a vessel. Instead of having a plaque, which is what I drew before, in my vessel, this time I'm going to talk about blood pressure being really high. So here we're talking about things like, let me write over here, high blood pressure or, I'd say, diabetes. So in situations like this, you can have lots and lots of pressure pushing out of the vessel. This is my little arrows talking about blood pressure. And as the pressure is pushing out, what happens is that some of the proteins from inside of the vessel-- let's say you have some protein in here-- get pushed out. They're pushed out into the vessel walls. And that vessel wall gets loaded with protein, now, extra protein that doesn't usually belong there. And it's got little protein everywhere, because it's being pushed out by all that high pressure. And over time, having all this protein here-- I'm drawing in pink-- is going to cause these vessels to start losing compliance. So all the way around, actually. They start losing compliance. And again, this is not how it always happens, but this is just an example of how it could happen. You could lose compliance this way. So this would be an example of how something that was soft is becoming very firm over time because of blood pressure related issues. All right, we'll pick up there next time.
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Gardner’s Two Tribes
imgresMathematical conundrums are not always the product of academic rigor. Sometimes they come from a recreational playground built on the foundation of logic and unique understanding. Beyond numbers and sets, mathematical thinking is rooted in the ability to extract patterns and make non-intuitive connections. The late Scientific American Mathematical Games columnist and writer, Martin Gardner was a master at communicating such patterns. Subsequently, his expositions influenced generations of math hobbyists and professional mathematicians alike. In reviewing Gardner’s book, The Colossal Book Of Mathematics, Dr. Persi Diaconis of Stanford University stated , “Warning: Martin Gardner has turned dozens of innocent youngsters into math professors and thousands of math professors into innocent youngsters…”
Though he influenced the field of recreational mathematics greatly, Gardner was not a professional mathematician. Starting with his monthly Scientific American column in 1956, his iconic logic and math oriented puzzles still hold the standard in recreational math literature. A simple example of this can be found in the following riddle Gardner wrote in his book Entertaining Mathematical Puzzles entitled “The Two Tribes”:
“An island is inhabited by two tribes. Members of one tribe always tell the truth, members of the other always lie.
A missionary met two of these natives, one tall, the other short. ‘Are you a truth-teller?’ he asked the taller one.
‘Oopf,’ the tall native answered.
The missionary recognized this as a native word meaning either yes or no, but he couldn’t recall which. The short native spoke English, so the missionary asked him what his companion had said.
‘He say yes,’ replied the short native, ‘but him big liar!’
What tribe did each native belong to?”
The answer is given by breaking the problem up into two cases. Suppose the tall one is of the tribe that always tells the truth. In this case, the tall native would have said yes. Likewise, If the tall native would have been of the tribe that always told lies, he still would have said yes. Since the missionary understood this, he knew the short native was telling the truth when he translated what the tall native said. Therefore, the missionary concluded that the short native was of the tribe that always told the truth and the tall native was of the tribe that always lied.
The strategy and thought processes behind solving such riddles is very similar to how a mathematician proves theorems. Gardner routinely placed mathematical methodologies into the solutions of his riddles and puzzles. The Pigeonhole Principle, theorems from Logic, Number Theory, Topology, etc. show up as regulars in Gardner’s playground of mathematical conundrums.
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2 Written questions
2 Multiple choice questions
1. They used masks, totem poles, food, rattles, and puppets. Only a family member could be a speechmaker. Celebrations were held in winter because they felt the spirits were closer. They had celebrations for totem pole raising, births, weddings, and funerals
2. They didn't pull too much bark from the tree which would kill the tree. They used wood to make plank houses, canoes, chests, dishes, toys, bows, arrows, rope, mats clothing, and blankets
2 True/False questions
1. Importance of totem poles to the KwatkiutlTotem poles represented each family. Only the important or rich had totem poles
2. Jobs of KwatkiutlMen went hunting for food. Women made blankets and food
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Bonanza for Lake Superior: Seiches Do More Than Move Water
Johnson Sea-Link II.
Researchers Steve Eisenreich and Joel Baker used a submersible, the Johnson Sea-Link II, to explore the depths of Lake Superior and seiches in 1985 and 1986. Photo courtesy of the Minneapolis Star-Tribune
If you’ve ever experienced a large seiche (pronounced “saysh”) on one of the Great Lakes, it’s something you’ll not soon forget. That so much water can be moved in a relatively short period of time is astounding. Before you know it you’re either left high and dry or inundated with water.
Whenever ice is not an inhibiting factor, wind or air pressure changes can cause the entire surface of a lake to rhythmically rock back and forth in the physical process that can form a seiche. According to David Schwab, a scientist with the Great Lakes Environmental Research Lab, “seiche” is a French word that means “to sway back and forth.” It was first applied by a Swiss lake scientist, Francois-Alphonse Forel in the late 1800s. Forel is also known as the founder of limnology, or the study of lakes.
In 1998 a seiche occurred in Two Harbors, Minnesota, that caused several hundred thousand dollars of damage to vessels loading iron ore at the Duluth Missabe Iron Range Railway Company docks. “We’ve had two seiches in the past that have surged a vessel almost 12 to 15 feet, causing the ship to damage shuttles on our shiploader, and the vessel incurred some damage,” said company dock manager David VanBrunt. Just last December, another large seiche occurred in the Duluth-Superior harbor.
Seiches generate currents within the lake’s water column. The strengths of these currents depend on the sizes of the seiches driving them. The smallest seiches drive currents with no significant effect on vessel navigation. The biggest seiches drive strong and unpredictable currents that can move vessels off course and aground or otherwise into harm’s way.
Seiche-driven currents do more than disturb moored vessels and influence navigation. They can impact lake biology. Upper lake organisms eventually die. Bacteria decompose these dead organisms, converting them into nutrients or fertilizer for future generations. To support life, a lake needs mechanisms for lifting nutrients from deeper waters into the sunlit surface waters where algae use photosynthesis to create new living tissue.
What can lift nutrients in this way? Sometimes winds move surface waters away from the shoreline. This causes upwelling, a process in which deeper waters rise to replace surface waters driven offshore. Upwelling does lift nutrients, but it isn’t as dependable as other mechanisms. Steady winds must blow in a direction that moves surface waters offshore. As you know, winds aren’t always steady, and they can blow in many directions.
In many of the shallower oceanic regions near land, tidal currents are strong enough to create eddies that lift nutrients from deeper waters to the surface independent of weather conditions. The Great Lakes have tidal currents too weak to lift significant amounts of nutrients. Knowing this has led scientists to ask the following question: In water bodies with low tidal ranges, can seiches act as tide-replacement mechanisms that lift nutrients from deeper waters to the surface?
In the 1980s, Sea Grant researchers Steve Eisenreich and Joel Baker decided to find out how seiches might influence the biological economy of water bodies with low tidal ranges. First, they needed to recognize the importance of what scientists call the nepheloid layer. This is a turbid, nutrient-loaded, particle-rich zone that hovers above the lake floor.
They lowered instruments from a ship to make measurements in Lake Superior. Their analysis of these measurements suggested that seiches either maintain the nepheloid layer or make it bigger by suspending previously-deposited sediments. Near Duluth during the summer, for example, they found near-bottom currents driven by a single seiche that were strong enough to triple the nepheloid layer’s vertical dimension from sixteen to forty-eight feet!
With financial support from Minnesota Sea Grant and the National Undersea Research program at the University of Connecticut, these scientists used a submersible to explore first Lakes Huron and Superior, then Lake Michigan. During dives to the floor of Lake Superior, Eisenreich and Baker were surprised by the abundance and variety of life in the sediments.
During their dives, Eisenreich and Baker watched organisms living in Lake Superior sediments stirring materials free and moving them up into the nepheloid layer. They found that these materials were loaded with nutrients that would otherwise be locked within the sediments, but now could be used by organisms that live higher in the water column. Eisenreich and Baker were immediately struck by the profound implications of what they had discovered: that a seiche-controlled nepheloid layer can be an important source of raw materials for the water column.
When you think about Lake Superior, remember that during most of the year, many small seiches repeatedly help to feed the lake’s living organisms. When you learn that another big seiche has occurred, rest assured that the living lake has been treated to a bonanza!
For more information on Eisenreich and Baker’s past research, look on the journal reprint page and our order form, items number JR 209 and JR 116.
By Ben Korgen
February 2000
Return to February 2000 Seiche
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History 2701 Wiki
Ottoman Tughra
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this wiki
Tughra (Imperial Cipher) of Suleiman the Magnificent
SacwhiteAdded by Sacwhite
Brief IdentificationEdit
This work of art was used as the imperial cipher for the Ottoman Empire's Sultan, Suleiman the Magnificent (r. 1520-1566). The tughra was used as a seal to signify the legality of official documents such as royal decrees, endowment papers, correspondence, and coins . The tughra was used not only by Suleiman, but also all other Ottoman sultans beginning in the fourteenth century . Each Sultan chose their own design from a prepared set of examples. They may have not been as embellished as Suleiman’s tughra, but the others had no lesser meaning.
Technical EvaluationEdit
The tughra was a seal drawn at the head of documents to institute the gravity of the notion and guarantee its authenticity [see Imber, 73]. The tughra was affixed upon all documents by the nisanci. He was the representative of the Chancery among the Imperial Council [see Inalcik, 93]. The nisanci would have been a calligrapher. These men were trained to write flawlessly and beautifully. They prepared their own ink and pens . After the initial inscription by the calligrapher, a court illuminator would fill in the decoration of the seal. In the represented picture of Suleiman the Magnificent’s tughra, the embellishment was with golden ink; a rare practice anywhere in the world.
The tughra is not just a picture used as a representation of authority, but contains writing in the design. The main portion of the body reads : "Sulaiman, son of Selim Khan, ever victorious." In the lower left corner, written in gold is: "This is the noble, exalted, sign-manual, the world-illuminating and adoring cipher of the Khakan [may it be efficient by the aid of the Lord and the protection of the Eternal]. His order is that..." The body of the document would then follow as stated above.
Local Historical ContextEdit
The tughra was a symbol of the Ottoman Empire. The sultans used the seal to signify their authority and rule. During the time of the depicted tughra, Suleiman the Magnificent was in power. Suleiman was the most prominent of all the sultans and ruled thelargest expanse of land at the height of the Ottoman Empire.At Suleiman’s time of power, the empire was very wealthy and had little direct threat [see Clot, 31].
Suleiman was the tenth sultan of the Ottoman’s reign. Ten is a perfect number to Muslims so Suleiman was held with high expectation. Even his name was selected at random and derived from Solomon in the Koran [see Clot, 31].
Suleiman’s interests are reflected by the beauty and complexity of his tughra. He was a well learned man and enjoyed the arts very much. Suleiman encouraged practice of the arts so much that he provided near unlimited funding for them and even took up writing poetry himself [see Clot, 269-270]. Among the arts was calligraphy; the basis of the tughra.
World Historical SignificanceEdit
The death of Suleiman brought grief throughout the empire. His reputation rose above and beyond that of all preceding sultans [see Clot, 297]. The tughra that Suleiman left behind is a reminder of just how great his empire had become. The Christians of Europe were so terrified of his might that they did not believe they could stand against an attack [see Clot, 299]. The world did not need a reminder of just how great Suleiman had become for he had created them himself. Not only in his love for art but in his conquest of land.
With the death of Suleiman came the decline and eventual collapse of the Ottoman Empire. Suleiman may have been to blame as he and his council had changed the ways of the palace and government from the early days of the sultan's rule. The rest of the West was in turmoil around this time and assisted in the decline of the states [see Clot, 302]. At this point the impact of Suleiman's tughra was ineffective.
Andrè Clot, Suleiman the Magnificent, The Man, His Life, His Epoch (London: Saqi 1992), 31, 269-270.
Colin Imber, The Ottoman Empire, 1300-1650, The Structure of Power (New York: Palgrave Macmillan, 2002), 73.
The British Museum, "Tughra of Suleiman the Magnificent."
Halil Inalcik, The Ottoman Empire, The Classical Age 1300-1600 (Great Britain: Ebenezer Baylis and Son Ltd, 1973), 93.
Metropolitan Museum of Art, "Tughra (Imperial Cipher) of Sultan Süleyman the Magnificent." Last updated April 19, 2011.
Metroopolitan Museum of Art, "Tughra of Süleyman the Magnificent."
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email a friend iconprinter friendly iconTut DNA
Page [ 4 ] of 9
Our search for Tutankhamun's mother and wife focused on four unidentified females. Two of these, nicknamed the "Elder Lady" and the "Younger Lady," had been discovered in 1898, unwrapped and casually laid on the floor of a side chamber in the tomb of Amenhotep II (KV35), evidently hidden there by priests after the end of the New Kingdom, around 1000 B.C. The other two anonymous females were from a small tomb (KV21) in the Valley of the Kings. The architecture of this tomb suggests a date in the 18th dynasty, and both mummies hold their left fist against their chest in what is generally interpreted as a queenly pose.
Finally, we would attempt to obtain DNA from the fetuses in Tutankhamun's tomb—not a promising prospect given the extremely poor condition of these mummies. But if we succeeded, we might be able to fill in the missing pieces to a royal puzzle extending over five generations.
To obtain workable samples, the geneticists extracted tissue from several different locations in each mummy, always from deep within the bone, where there was no chance the specimen would be contaminated by the DNA of previous archaeologists—or of the Egyptian priests who had performed the mummification. Extreme care was also taken to avoid any contamination by the researchers themselves. After the samples were extracted, the DNA had to be separated from unwanted substances, including the unguents and resins the priests had used to preserve the bodies. Since the embalming material varied with each mummy, so did the steps needed to purify the DNA. In each case the fragile material could be destroyed at every step.
At the center of the study was Tutankhamun himself. If the extraction and isolation succeeded, his DNA would be captured in a clear liquid solution, ready to be analyzed. To our dismay, however, the initial solutions turned out a murky black. Six months of hard work were required to figure out how to remove the contaminant—some still unidentified product of the mummification process—and obtain a sample ready for amplifying and sequencing.
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The Destruction of Jerusalem
Enlarge (18MB) Zoom in
French, Paris, about 1415
Tempera colors and gold leaf on parchment
16 9/16 x 11 5/8 in.
MS. 63, FOL. 237
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In the miniature depicting the Siege of Jerusalem in 70 A.D., the Roman Emperor Titus, who directed the battle, sits enthroned in a tent while his soldiers storm the city. As is typical for the art of this period, the scene is anachronistic: the figures wear armor of the 1400s, and the city of Jerusalem is a medieval walled city with battlements, wood-and-plaster houses, and even a Gothic church. To give the illusion of recessed space, the artist used an intuitive rather than a mathematical perspective, stacking the farther buildings on top of those in the front. Despite this innovative method for representing space, he also used an un-naturalistic background of checkered squares for the sky, instead of blue paint. This miniature complements the only other full-page miniature in the manuscript, "Adam and Eve," implying a parallel between The Fall and the eventual destruction of Jerusalem. Just as Adam and Eve were punished for disobeying God, medieval Christians believed that the destruction of Jerusalem resulted from the Jews' failure to accept Jesus as the Messiah.
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You’ll see many false nautical origins on these pages. People like to ascribe nautical origins to words and phrases, even when they’re not accurate. But in this case, scuttlebutt does indeed come from the age of sail.
Scuttlebutt is an early 19th century nautical term for an open cask of water kept on deck for use by the crew. The term comes from scuttle (to cut a hole in) + butt (a large cask). Sailors would gather about the cask and trade stories and gossip, much like modern office workers do at the water cooler or coffee pot. By the turn of the 20th century, American sailors began using the term scuttlebutt to refer to these sea stories and gossip. And eventually the term became associated with any gossip or rumor and divorced from its nautical origins.
Scuttlebutt is a compound of scuttle + butt. A scuttle is a small hole or hatch in a ship’s deck or side, used for lighting, ventilation, or, if large enough, for the passage of people and stores. It’s origin is a bit uncertain. It probably comes from the French écoutille or escoutille, meaning hatch, which is cognate with the Spanish escotilla. The exact relationship between the English, French, and Spanish words are what is uncertain. English use dates to at least 1497. From the Naval Accounts of Henry VII:
A chayne of yron for the skottelles of the haches.
(A chain of iron for the scuttles of the hatches.)
From this sense developed the verb to scuttle, meaning to bore a hole in something, in particular to punch holes in the hull of a ship in order to deliberately sink her.
Butt is another word for cask or barrel. It has cognates in most of the Romance languages and ultimately comes from the Latin butta or buttis, meaning cask or wineskin. English use dates to at least 1423.
We have this citation from George Forster’s 1777 A Voyage Round The World that shows the development and original meaning of the term scuttlebutt:
A centry [sic] was placed at the scuttled-cask, and a regular allowance of water was daily served out.
And in 1805, we see the appearance of scuttlebutt in print, from J.J. Moore’s Midshipman’s or British Mariner’s Vocabulary:
Scuttle-butt, or cask, is a cask having a square piece sawn out of its bilge and lashed upon the deck. It is used to contain the fresh water for daily use.
The sense meaning gossip or information developed among American sailors. It seems to have been current by the turn of the 20th century. In 1901, the magazine Smoking Lamp carried a column of miscellany titled Scuttle butt. The following appears in the USS Oklahoma Sea-Bag of 25 July 1920:
The Scuttle Butt has justified its existence as a source of prognostic rumor. The water is freezing cold—the Scuttle Butt is iced...Come down and get a drink of cold water.
And the 18 July 1933 issue of Leatherneck uses the term entirely as metaphor:
We will endeavor to convey all of the scandal, scuttle-butt, dope and dopes.
(Source: Oxford English Dictionary, 2nd Edition)
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CDC Home
Genomics and Health
Skin Cancer Awareness
Two women with hatsSkin cancer is the most common form of cancer in the United States. Most skin cancers are caused by exposure to ultraviolet rays from the sun. People who have a close relative (parent, sibling, or child) with a specific type of skin cancer called melanoma may be at greater risk of developing the disease than the general population. The best way for people to prevent skin cancer is to protect themselves from the sun.
Centers for Disease Control and Prevention
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Contact Us:
• CDC-INFO Contact Center
Phone: 800-232-4636 (800-CDC-INFO)
Hearing Impaired: 888-232-6348
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Did you know?
- definition
What are red words?
verb British English pronunciation: shine /ʃaɪn/
Word Forms
present tense
present participleshining
past tenseshone
past participleshone
1. 1
[intransitive] if the sun shines, it produces a bright light and the weather is usually warm
The sun was shining brightly.
1. a.
used about the moon, stars, lights, and other things that produce light
The headlights of oncoming cars were shining through the mist.
2. 2
[intransitive] to have a bright attractive appearance
The wooden tables had been polished until they shone.
Her hair shone like gold.
3. 3
[intransitive] if people's eyes or faces shine, they look extremely happy or excited
The child's face was shining with excitement.
4. 4
[transitive] to make the light from a torch or other light shine in a particular direction
Kobe shone the torch slowly around the room.
5. 5
[intransitive] to show that you have a lot of skill when you do something
It's time we gave some of the younger players a chance to shine.
phrasal verbs
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global English and language change from our blog
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Cottonwood ( Populus)
Cottonwood is a domestic hardwood
Cottonwood includes several species of the genus Populus. Most important are eastern cottonwood (P. deltoides and varieties), also known as Carolina poplar and whitewood; swamp cottonwood (P. heterophylla), also known as cottonwood, river cottonwood, and swamp poplar; black cottonwood (P. trichocarpa); and balsam poplar (P. balsamifera). Eastern and swamp cottonwood grow throughout the eastern half of the United States. Greatest production of lumber is in the Southern and Central States. Black cottonwood grows on the West Coast and in western Montana, northern Idaho, and western Nevada. Balsam poplar grows from Alaska across Canada and in the northern Great Lakes States.
The heartwood of cottonwood is grayish white to light brown. The sapwood is whitish and merges gradually with the heartwood. The wood is comparatively uniform in texture and generally straight grained. It is odorless when well dried. Eastern cottonwood is moderately low in bending and compressive strength, moderately stiff, moderately soft, and moderately low in ability to resist shock. Most strength properties of black cottonwood are slightly lower than those of eastern cottonwood. Both eastern and black cottonwood have moderately high shrinkage. Some cottonwood is difficult to work with tools because of its fuzzy surface, which is mainly the result of tension wood.
Primary Uses
Cottonwood is used principally for lumber, veneer, pulpwood, excelsior, and fuel. Lumber and veneer are used primarily for boxes, crates, baskets, and pallets.
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Essay by crimsonbutterflyHigh School, 11th gradeA+, November 2006
download word file, 5 pages 1.0
The basic structure of Great Expectations follows a chronological development of Pip's life; from his childhood innocence, to his disillusioned expectations, finally his rejection of the high life and a circular succession ending back at the beginning. This chronological structure of which Dickens narrates exemplifies Pip's learning process through his moral and emotional turmoil and complies with the opportunity to generate a realistic setting. For example, Pip's description of London, "a most dismal place; the skylight eccentrically patched like a broken head, and the distorted adjoining houses looking as if they had twisted themselves to peep down at me through it," creates an archaeologically realistic description of London, and hints a sense of foreboding, foreshadowing the futility of Pip's expectations. This ideology developed through...
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Examining Evolution By: Cohl and Eric
Part 1: Darwin's Voyage
Highlighted stops have illustrations to go along with Darwin's observations.
1. Departure from Plymouth, England (1831 December 27)
2. First landing was Madeira Island (4 January 1832)
3. H.M.S. Beagle arrived at the Cape Verde Islands (16 January 1832)
4. Next landing was at Feb 28, 1832 in Salvador, Brazil
5. The Beagle arrived at Rio de Janeiro, Brazil, on 3 April 1832
6. Arrive in Montevideo (July 26, 1832)
5. Tierra del Fuego, Argentina (Dec 24, 1832)
6. Falkland Islands (Mar 1, 1833)
7. Rio Negro, Argentina (Aug 1, 1833)
8. Chiloe Island, Chile (Jun 12,1834)
9. Galapagos Islands (Sept 15th, 1835)
10. Landed in Matavai Bay, Tahiti on Nov 15, 1835.
11. Arrive in Bay of Islands, New Zealand (Dec 21, 1835)
12. Anchored at Sydney Cove, Australia on Jan 12, 1836.
13. On February 5th, 1836 the HMS Beagle landed at Hobart Town, Tasmania.
14. Arrived in King George's Sound, Australia on March 6th, 1836.
15. On April 1st, 1836 the HMS Beagle arrived at the Cocos Islands.
16. Port Louis, Mauritius (April 29, 1836)
17. Arrive in Simon's Bay, South Africa on May 31, 1836
18. HMS Beagle arrived at St. Helena Island on July 8, 1836
19. Landed on Ascension Island (July 14, 1836)
20. HMS Beagle arrived at Bahia de los Santos, Brazil before taking the voyage back to England. (August 1, 1836)
21. Arrived at Porta Praya at the Cape Verde Archipelago for just five days. (August 31, 1836)
22. HMS Beagle arrived at the Azores and anchored at Terceira near the town of Angra on Sept. 20th, 1836.
23. HMS Beagle finally arrived home after a voyage of four years, nine months, five days. They arrived in Falmouth, England on October 2, 1836.
Darwin had sailed 40,000 miles around the world, explored over 2,000 miles inland over almost 5 years.
Salvador, Brazil - When exploring Salvador, Darwin was remarked because of the rain forest, and took a deep interest in this specific ecosystem, and the wildlife within it. This can be assumed because of how long he stayed in Salvador.
Argentina - When exploring Bahia Blanca, Darwin came across sets of bone from fossilized mammals at two separate locations. He was shocked when he found an outer shell of an extinct form of armadillo, while in the presence of another species of armadillo. The second set of bones he found belonged to an extinct giant ground sloth. This was especially strange because both of these animals belonged to the same primitive group of mammals classified as Order Edentata. The main question mark Darwin had through this discovery was 'Why would fossil remains and modern species found on the same continent resemble each other so closely?'
Falkland Islands - When Darwin explored the Falkland Islands he noticed that they were desolate, and there wasn't much there to explore other than a few animals and fossils. His most valuable discovery from this stop was most-definitely the fossils which were mainly brachiopods, but also some crinoids. At the time of their discovery, fossils like these were little known beyond Europe and were regarded as almost the oldest known life on Earth so this was a huge stepping stone for Darwin and his crew.
Galapagos Islands - When Darwin explored the many Galapagos Islands, he discovered that finches were common throughout the islands. He noticed however, that the finches had different lengths of beaks and eating habits, depending on their specific environments, or ecosystems on their islands. He didn't actually think much of this discovery at the time, and it took him leaving and taking his focus off of the finches, before he connected the dots and used them as large evidence behind his theory of natural selection.
Keeling Islands (Cocos Islands) - When exploring the Keeling Islands, Darwin put one of his theories to the test. He was studying coral reefs that were growing around islands to test his theory of atoll formation. His testing was successful, as he wrote about it in his journal, and later went on to publish his theory.
Waiting Several Years to Publish Findings Journal:
I think that Charles Darwin waited so long to publish his findings on evolution and natural selection because he had a sense of what the repercussions of his actions would be. The repercussions mentioned would be that once it caught wind, he would become the center of attention in the religious and scientific circles, and would be in the middle of a large debate, which is why Darwin originally wanted to have his book published after he passed away.
To expand on the main reason (in my opinion), I think Charles Darwin waited so long to publish his findings because his theory held many implications towards religion. This is because his theory stated that species evolved from one another, which was contrasting Genesis, as it stated that God created the world in six days; however, evolution states that the world and the creatures in it progressed over the course of millions of years.
He knew that to the average person, who was much less educated within the field of science, that they would see these ideas as ludicrous, outlandish, and would deny without a second thought. This may be why he had such hesitation, as he knew in his mind that he was correct, but if he was labeled as a crazy man, all of his hard work would be discredited because of ignorance.
Part 2: Darwin's Life and Influences
Charles Darwin, 73, of Shrewsbury, England, passed away on April 19th 1882 in Kent , England. Charles suffered a fatal heart attack, after a history of heart attacks throughout the years leading up to this.
Charles was born in Shrewsbury, England to Robert & Susannah Darwin on 12th February 1809. He went to school at Anglican Shrewsbury School. Later graduating from the University of Edinburgh Medical School with his brother Erasmus in the October of 1831. He married Emma Darwin on the 29th of January 1839 in Shrewsbury, England. He was a huge contributor to the field of science for 51 of years. He founded the theory of “Survival of the fittest” and served a huge contribution to the field of science. His work has taken on more and more wind throughout the years, and evolution is now taught in the educational system, as it covers his many theories and contributions to the evolutionary studies.
Charles is survived by his 10 children. (Anne, George, Francis, Henrietta, Horace, Leonard, William, Charles, Mary, and Elizabeth Darwin).
Memorial will be held at Down House, Kent, England. All donations and charity will be forwarded and appreciated by the Darwin family.
Comparison Chart has been handed in through Showbie.
Part 3: Galapagos Islands
Travel Brochure: Made with PowerPoint, so unable to present through Adobe Slate, file has been sent through Showbie.
Part 4: Glossary
Variations - The occurrence of an organism in more than one distinct color or form.
Descent with modification - Descent with modification is passing traits from parent to offspring.
Genetic variation - Genetic variation refers to the differences in genes between individual members, or the frequency in which the various gene types are expressed.
Genetic Drift - Difference in the frequency of different genotypes in small groups, increasing the chance of a disappearance of a gene.
Natural Selection - The process where a species better adapted to their environment has a higher tendency to survive and produce offspring.
Speciation - The formation of new and distinct species during evolution.
Microevolution - Evolutionary change in a species and/or small group of organisms over a short period.
Macroevolution - Major evolutionary change. “The term applies mainly to the evolution of whole taxonomic groups over long periods of time.”
Population Bottleneck - A sharp reduction of population due to environmental aspects (earthquakes, tsunami, ect..)
Founder Effect - “The reduced genetic diversity that results when a population is descended from a small number of colonizing ancestors.”
Survival of the Fittest - The continuation of a species survival in its best adapted environment, while others become extinct. Ex. Giraffes with long necks strive in their population because they are more healthy and can eat more regularly, without having to travel long distances for food, making them more likely to survive and pass down their genes increasingly pushing out the short necked Giraffe genes from the gene pool.
Part 5: Evidence for Evolution
Homologous Features are structures that are similar in related organisms because they were inherited from a common ancestor. These structures may or may not have the same function in the descendants.
This supports the theory of evolution because it proves that vastly different species all have similar structures, showing that they must have come from a common ancestor, expanded on with the following examples:
A dolphin’s flipper, bird’s wing, cat’s leg, and the human arm are considered homologous structures. Whereas human beings have bones such as the humerus, ulna, radius, wrist bones, and fingers, these features appear as similar bones in form in the other animals. Bats, whales, and many other animals have very similar homologous structures, demonstrating that these creatures all had a common ancestor.
Mammals share the homologous structure of the vertebrae in common. For instance, in spite of its height, the giraffe has the very same number of neck bones (seven) as a giant whale and a tiny human being.
Our eyes are homologous to the eye bulbs which blind creatures who live in caves have on their heads.
The tailbone in human beings is so-named because it is a homologous structure to the beginning of many animals’ tails, such as monkeys. It is known as "vestigial" because it is the last vestige of what was once a tail, but I will talk about that more in-depth later on.
The genetic code among all living things is homologous – extremely similar although other genetic codes exist. This suggests a common ancestor.
Homologous Structures
Analogous structures are structures that are similar in unrelated organisms. The structures are similar because they evolved to do the same job, not because they were inherited from a common ancestor.
Evidence of evolution while looking at analogous structures can be done, as it shows how different species have evolved to become more similar. Examples of these features include:
An example of this is the wings of a bat and a bird, as they are similar looking on the outside, and have the same function, but wings evolved independently in the two groups of animals. This is apparent when you compare the pattern of bones inside the wings.
Another example of an analogous trait is fins. Animals such as penguins and fish both have fin-like structures to help them navigate through their aquatic environments. However, because one is a bird and one is a fish, it is clear that the fin evolved in these very different species because it was the best functional feature for the environment they inhabit instead of from a common ancestor.
Analogous traits are not limited to visual body structures; behavioral traits can also be analogous. Bird songs are quite varied, not just between different species but also between different flocks. However, it has been found that some bird species that are quite unrelated can develop analogous song characteristics if held together in similar conditions for periods of time in a lab.
Analogous Structures
Structures like the human coccyx are called vestigial features. Evolution has reduced their size because the structures are no longer used. The human appendix is another example of a vestigial structure. It is a tiny remnant of a once-larger organ. In a distant ancestor, it was needed to digest food. It serves no purpose in humans today.
Proof of evolution with vestigial features is quite obvious, as the only reason a species would have a structure in their body that isn't used anymore, is because the have evolved from a past ancestor who did have a function for that structure. Vestigial structures are often homologous to structures that function normally in other species. Therefore, vestigial structures can be considered evidence for evolution, the process by which beneficial heritable traits arise in populations over an extended period of time. The existence of vestigial traits can be attributed to changes in the environment and behavior patterns of the organism in question. As the function of the trait is no longer beneficial for survival, the likelihood that future offspring will inherit the "normal" form of it decreases. In some cases the structure becomes detrimental to the organism. This is shown with a multitude of examples throughout the animal kingdom, including the following:
The erector pili are smooth muscle fibers that give humans "goose bumps". If the erector pili are activated, the hairs that come out of the nearby follicles stand up and give an animal a larger appearance that might scare off potential enemies and a coat that is thicker and warmer. Humans, though, don't have thick furs like their ancestors did, and our strategy for several thousand years has been to take the fur off other warm looking animals to stay warm.
Biologists believe that for 100 million years the only vertebrates on Earth were water-dwelling creatures, with no arms or legs. At some point these "fish" began to develop hips and legs and eventually were able to walk out of the water, giving the earth its first land lovers. Once the land-dwelling creatures evolved, there were some mammals that moved back into the water. Biologists estimate that this happened about 50 million years ago, and that this mammal was the ancestor of the modern whale. Despite the apparent uselessness, evolution left traces of hind legs behind, and these vestigial limbs can still be seen in the modern whale. There are many cases where whales have been found with rudimentary hind limbs in the wild, and have been found in baleen whales, humpback whales, and in many specimens of sperm whales.
In general, wings of a bird are considered complex structures that are specifically adapted for flight and those belonging to these flightless birds are no different. They are, anatomically, rudimentary wings, but they could never give these bulky birds flight. The wings are not completely useless, as they are used for balance during running and in flagging down the honeys during courtship displays.
Vestigial Structure
Fossils provide solid evidence that organisms from the past are not the same as those found today; they show a progression of evolution. Scientists calculate the age of fossils and categorize them to determine when the organisms lived relative to each other. The resulting fossil record tells the story of the past and shows the evolution of form over millions of years. For example, scientists have recovered highly-detailed records showing the evolution of humans and horses . The whale flipper shares a similar morphology to appendages of birds and mammals, indicating that these species share a common ancestor . Over time, evolution led to changes in the shapes and sizes of these bones in different species, but they have maintained the same overall layout, called homologous features. Many examples of fossils leading to evolutionary advances include:
Organisms have changed significantly over time. In rocks more than 1 billion years old, only fossils of single-celled organisms are found. Moving to rocks that are about 550 million years old, fossils of simple, multi cellular animals can be found. At 500 million years ago, ancient fish without jawbones surface; and at 400 million years ago, fish with jaws are found. Gradually, new animals appear: amphibians at 350 million years ago, reptiles at 300 million years ago, mammals at 230 million years ago, and birds at 150 million years ago. As the rocks become more and more recent, the fossils look increasingly like the animals we observe today.
Part 6: Controversy about Evolution
This cartoon clip is from a TV show called South Park, which is intended for adult viewers and doesn't really target the younger audience. It pretty much shows what someone who lacks an education would think of evolution or has no understanding of it. I can’t really explain the cartoonist's opinions because upon my knowledge South Park is generally just meant to criticize evolution for pure mockery.
Darwin’s an Ape? Upon researching the most apparent photo to appear has by far been the Charles Darwin head on an ape, and there really isn't any information on why it's such a trend. Audience wise it could be targeting anyone from younger to older ages , anyone who really has any knowledge of Darwin could easily find these photos as they are EVERYWHERE.
Article #1 “C-Sections May Change the Course of Human Evolution”
In this article, it briefly describes the theory of “Survival of the Fittest” then covers on how recent data gathered on birth internationally shows an high increase in “obstructed births” meaning that the baby cannot fit through the birth canal, the most common factor in this is “cephalopelvic disproportion” meaning there was a mismatch between the baby’s head and the carriers pelvis. Which now a day is easily fixed by performing a C-section. If not performed the mother would pass away during birth. But because of the C-section the mother lives and passes on its gene of the narrow pelvis thus creating a long line of narrow pelvis woman which theoretically eventually lead to ALL births needing to be C-sections. But this wouldn’t be apparent until years and years into the future. But if we would not perform C-sections Darwin’s theory of “Survival of the fittest” would sort this problem out by essentially “whipping” out all the narrowed pelvis woman.
Article #2 “What Happens When Tech Takes Control of Evolution”
Firstly, the article touches on how all species originally followed a set path but for the first time ever “homo sapiens” have taken control over their destiny and pave their own way. Which according to Daniel Wilson, “You can graph human evolution, which is mostly a straight line, but we do get better and change over time, and you can graph technological evolution, which is a line that's going straight up. They are going to intersect each other at some point, and that's happening now.”. For examples Genetic engineering and neurotechnology are ways we shape our own form of evolution, Scientist say soon we’ll be able to think what kind of species we’d like to be and we will be able to shape and self-evolve ourselves to be the species we self-imagined. And then in touches into genetic engineering and mutation, and why if we can us Genetic engineering to solve medical problems why not use it to enhance our species beyond just medical traits.
Part 7: Reflection
Eric :
In the ISP based on evolution it touched on Darwin’s voyage and his theory of “Survival of The Fittest”. During my time researching on this topic my beliefs and thoughts based around evolution hasn’t changed at all really, I always chose to believe evolution over other religions because I found that evolution had the strongest information behind to back it up, there was always an answer for when someone tried to prove it wrong, I thought evolution to be the most logical in my point of view even after researching on this topic I am still a strong believer of its theory because to me logically it’s the one thing that makes sense of how everything is today. In the context of how I view it , I now have a better understanding of how and why certain animals are in region specific areas , such as why there’s lions in Africa but none in the Arctic. All because of Darwin’s theory Survival of the fittest where animals are evolved to adapt in their region specific areas, such as lions in the hot African weather won survive in cold arctic nights.
Question wise, the only thing I’d really want to know is a definite answer on how everything came to be and not just several “theories” but regardless I still enjoyed researching and completing this assignment and has benefited me in learning more about the theory of evolution.
When reflecting on my experience learning about evolution, I have had a slight change in my views of this subject. My ideas have only been skewed slightly when working on the controversy about evolution section of this assignment. Before this assignment, I assumed that all of Darwin’s theories on evolution were the most accepted and agreed upon, but when researching I found that there have been many advancements in this field of science, and there have been more recent theories that I agreed with more. An example of this was how some of his evidence of evolution and common descent were weak, such as his evidence of small-scale changes, including the modest changes in the size of finch-beaks or slight changes in the colour frequencies in the wings of “peppered moths”, which shows microevolution, not macroevolution. I did however confirm that for the most part (other than a few little discrepancies), my beliefs have been confirmed in the field of evolution. Even without doing this assignment, I have looked into the different available options for life, and the beginning of life, and have already concluded that I believe in the science as there is far more anecdotal evidence behind it and it isn’t just purely based on faith, such as religion for instance.
A question that I still have would be, if a species was in danger of becoming extinct, would the evolutionary process be accelerated, and if so, by what rate would it be accelerated? Another question I would love the answer to would be, how much proof would be needed to take evolution from a theory to a fact?
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"edu_score": 3.59375,
"fasttext_score": 0.6631688475608826,
"language": "en",
"language_score": 0.9683822989463806,
"url": "https://spark.adobe.com/page/C0cUCqDBTySq4/"
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fluence (of particle radiation)
The number of radiant-energy particles emitted from or incident on a surface in a given period of time, divided by the area of the surface.
NOTE 1 The equation "fluence = N/A" applies, where N and A represent the quantities number of particles and area. Fluence can also be calculated by integrating the flux density over the given period of time, e.g., as in a run.
NOTE 2 The unit symbol (e.g., cm²) does not identify particle type. The particle name may be placed before the term, e.g., "neutron fluence", or in the spelled-out unit name, e.g., "neutrons per square centimeter".
NOTE 3 Fluence of particle radiation incident on a surface is maximized when the surface is perpendicular to the direction of the incident particle flow.
JESD57#, 12/96
JESD89A#, 10/06
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<urn:uuid:d3d28741-9c5d-4ff7-bbcd-b048f72ab1f1>
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"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.6875,
"fasttext_score": 0.5741621851921082,
"language": "en",
"language_score": 0.8302748203277588,
"url": "http://www.jedec.org/standards-documents/dictionary/terms/fluence-particle-radiation"
}
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Newburyport Harbor
Review and History
Newburyport Harbor lies at the mouth of the Merrimack River in northeastern Massachusetts. Newburyport Harbor is about 48 kilometers (30 miles) north-northeast of Boston and about 30 kilometers (18 miles) southwest of Portsmouth, New Hampshire. Colonial Newburyport Harbor was a busy shipbuilding and fishing port with a big merchant fleet.
Today, light manufacturing and tourism are the base of Newburyport Harbor's economy, but storing and maintaining recreational boats is still important source of income. Newburyport Harbor streets are lined with noble homes built by sea captains and ship owners. Located on the East Coast's important Interstate Highway 95, Newburyport Harbor is the terminus of Boston's commuter rail line. In 2010, more than 17.4 thousand people called Newburyport Harbor home.
Port History
The indigenous Massachuset Nation inhabited the future Newburyport Harbor area long before settlers arrived from Europe. It is likely that the Massachuset are descendants of people who had lived in the Northeastern United States since the last glaciation period that ended up to 30 thousand years ago.
Archaeological finds support the idea that people lived in the Newburyport Harbor area for at least 6.5 thousand years. The Massachuset were farmers and fishers who migrated from season to season between inland and coastal villages. Plague brought by Europeans severely depleted the population of the Massachuset in the early 17th Century. Then, during the Great Migration of 1630 to 1640, more than twenty thousand English settlers arrived, driving the native people away.
John Eliot converted some Massachuset to Christianity, and they created an alphabet and a translation of the Bible into their language. The people were confined to praying villages by English law where they tried to convert more of the Massachuset.
The colonists did not trust the Massachuset after King Philip's War, a mid-17th Century conflict between the English and their allies and other native tribes. The Commonwealth of Massachusetts passed a law in 1869 that eliminated the Massachuset Nation's sovereignty and made them citizens of the US. The modern Massachuset-Ponkapoag Tribal Council represents the descendants of the tribe who live in Natick and Brocton.
Newburyport Harbor was originally settled as part of Newberry Plantation (today's Newbury) in 1635. In 1764, Massachusetts' General Court authorized creation of Newburyport by separating it from the town of Newbury in recognition of the different characters of the two areas and the disputes that had resulted. Newburyport Harbor was populated by merchants and traders, while Newbury was home to many farmers.
The infant Newburyport Harbor was Massachusetts' smallest town. It contained three shipyards and several ferries traveling to Portsmouth and Boston. Prosperity made Newburyport Harbor a city by the early 1850s. Newburyport Harbor was a center for shipping, fishing, and shipbuilding. It was also home to a silverware manufacturer. Distilleries imported molasses from the West Indies and exported rum.
It was not legal to buy slaves in Massachusetts, but slaves bought somewhere else were legal. Many of the stately homes on Newburyport Harbor's High Street were run by Native American and African slaves until the American Revolution when the Massachusetts General Court abolished slavery completely.
After the Revolution, abolitionism took root in Newburyport Harbor. Several residents made significant contributions to the operation of the Underground Railroad. Many anti-slavery meetings led by William Lloyd Garrison were held in Newburyport Harbor's Brown Square.
Newburyport Harbor's busy fishing fleet operated from the mouth of the Merrimack River to Georges Bank. During the American Revolution and the War of 1812, Newburyport Harbor was also a privateering center. By 1832, many local ships were engaged in the whaling fleet. Many clipper ships were built in Newburyport Harbor during the 18th and 19th Centuries.
In spite of its historic prosperity, Newburyport Harbor's city center was neglected and almost abandoned by the middle 20th Century. Suburban strip malls and improved highways took business from downtown Newburyport Harbor. In the early 1970s, plans were made to destroy the historic downtown structures. Before this happened, Newburyport Harbor received a federal grant that made it possible to keep the historic buildings.
Restorations and renovations continued in Newburyport Harbor's downtown throughout the decade of the 1970s. They were so successful that Newburyport Harbor is now an example of how preservation can maintain historic architecture and heritage while also providing functional and comfortable space.
Review and History Port Commerce Cruising and Travel Satellite Map Contact Information
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"edu_int_score": 4,
"edu_score": 3.703125,
"fasttext_score": 0.11561506986618042,
"language": "en",
"language_score": 0.9619585275650024,
"url": "http://www.worldportsource.com/ports/review/USA_MA_Newburyport_Harbor_3803.php"
}
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Essay by Monie9942High School, 10th gradeB, November 2014
download word file, 3 pages 0.0
Reynolds 1
Reynolds 1
Reynolds 1
Marissa Reynolds
Mr. Molchan
Period 2
1 November. 2014
The gladiatorial games served a number of purposes in roman society. One of the purposes were for the entertainment of Romans. The games were also used for punishment for anyone who committed a crime. The purpose of the game was to publicly execute the gladiators. Most gladiators were prisoners of war, slaves or criminals sentenced to serve in games. The Romans wanted to show the consequences for anyone who went against them.
The passage taught readers that Roman form of crime and punishment was harsh and cruel. They did not care about the people they trained or the people they locked up overall. Especially if the best way to die was being killed in the arena. "Of The many was for a slave to die, this was the most bearable: a single sword thrust to the neck, a gout of blood, and merciful oblivion" (Baker 152).
To the Romans anyone who defied them were sent to cruel and unusual punishment. "Tunic covered with pitch, a burning torch promising the unendurable: a screaming death as one's flesh was destroyed by fire..Or crucifixion" (152 Baker). They took their punishment to heart.
To Romans justice and social morality was served oddly. In the arena every social class had its own seat. Each social class was treated differently in a rude way. "The knights, tribunes and citizens then took their places directly above the podium in the first and second maenianumâ¦Behind this were the sections where non-citizens were allowed to sit, along with the slaves and women"(Baker 157). It seemed as if the poorer non citizen folks got treated as a
Reynolds 2
slave did. To them all the justice needed was served in the game. All slaves and...
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<urn:uuid:1d4db376-b3e7-4703-a324-2b8500410acc>
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{
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"edu_int_score": 4,
"edu_score": 3.65625,
"fasttext_score": 0.08658045530319214,
"language": "en",
"language_score": 0.9848694801330566,
"url": "http://www.writework.com/essay/gladiators-5"
}
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Study: short legs made human predecessors better fighters
Breaking News
Our ape-like predecessors kept their stout figures for 2 million years because having short legs ironically gave them the upper-hand in male-male combat for access to mates, finds a new study.
Living from 4 million to 2 million years ago, early hominins in the genus Australopithecus are considered immediate predecessors of the human genus Homo, and had heights of around 3 feet 9 inches for females and 4 feet 6 inches for males.
Until now, the squat physiques of australopiths and other human predecessors were considered an adaptation for climbing in tree canopies. Like surfing or any other sport that requires balance, having a lower center of mass boosts stability and, in turn, success at the activity.
"The old argument was that [apes] retained short legs to help them climb trees that still were an important part of their habitat," said the study author David Carrier, a biologist at the University of Utah. "My argument is that they retained short legs because short legs helped them fight."
comments powered by Disqus
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<urn:uuid:213b497c-1cd9-4e05-809a-432d1f83dd54>
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{
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"edu_int_score": 4,
"edu_score": 3.53125,
"fasttext_score": 0.03800445795059204,
"language": "en",
"language_score": 0.9618142247200012,
"url": "http://historynewsnetwork.org/article/36435"
}
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Thursday, January 20, 2011
Flood Simulation HowTo
EDIT 26 Jan 11: changed relative to ground to absolute, thanks to Google Earth Blog
In his novel 'Book of Dave', Will Self imagines a world in the future where sea levels have risen over a 100m.
This destroys civilization as we know it but leaves London skyscrapers still standing half underwater in the sea - the remaining humans who live on 'Ham' (an island created from the rising sea surrounding the high ground of Hampstead Heath, London) climb one of these which they call 'Central Stack' to capture seagulls. As the book has a map of Ham in the front I played around in Google Earth to see how accurate the boundary of the island actually was, as it happens, Will's imaginary island is what would really occur if sea level rose that far.
I realised the technique I used (one a teacher pointed out to me at a training session a while back) could be used in a lesson to visualize rising sea levels or ancient ice sheets. If you draw a polygon and give it an altitude that is about ground level the sheet created will disappear below the ground where the land is higher but be visible where the land is lower. Here's how to create a series of these sheets in a folder so you can show a sequence of increasing sea levels :
1. Click the Temporary Places folder in the Places column (it will get a background) then right click > Add > Folder. Add a name in the dialogue box and tick the 'Show contents as options' box. You'll see why in a moment.
2. Navigate to a location you want to 'flood' in the main screen. Right click the folder you've just created > Add > Polygon. Move the dialogue screen that opened out of the way (I move it to the bottom of the screen) and click the 4 corners of a square. Make it less than 10 miles across otherwise wierd things happen to the layer because of the curvature of the earth (I think, see note below)
3. Drag the dialogue box back into view and under the 'Style, Color' using the controls titled 'Area' select an appropriate color for the square (blue for sea level rise, white for an ice sheet?) also select an opacity of 30% or so.
4. Under the Altitude tab choose an altitude of 100m and then select 'Relative to Ground' 'Absolute' in the pull down menu. This will raise your colored square 100m above the ground.
5. Name your square something sensible but with a '100' in it (e.g. "London 100m") then click OK.
6. Now right click the element you created in the Places column and select copy. Right click the copy >Properties > Altitude and change the altitude to 200m. Change the name to replace 100 with 200 and click OK.
7. You should now have 2 sheets, one at 100m altitude and one at 200m. Clicking in the circles turns one on and the other one off automatically.
8. Experiment with altitudes that works for your chosen location, copy and paste more sheets if necessary by repeating step [6] - within the folder you created only one sheet will be visible at any one time.
9. Right click the folder and select 'Save As' to save and send to someone else.
3D Buildings: It's a lot of fun to turn on the 3D buildings layer whilst you have sheets visible in the layers column, as in the screeen shot the layers will show how deep buildings would be sunk in the sea - not sure if any of those in the screen shot are Central Stack.
Absolute Heights: Experimenting with the levels, the sheet behaves oddly, it doesn't meet the land at the height you would expect. I'm not sure why this is but it may do with the curvature of the earth (in the middle of a big square the earth will protude through a level sheet even though there is no topography). If anyone has a definitive answer I'd like to know.
Surface Flicker: If you zoom into the layers from a distance you may see line of where land meets sheet flicker and change. This is because GEarth creates the view of the earth you see by taking the satellite images and draping them over a set of 'posts' it builds rather like a marquee tent. If you view the ground from a higher altitude GEarth uses fewer posts so the surface changes as you zoom in and out. There is a way around this but its fiddly, I'll post about it if anyone's interested.
Jack said...
This is great - really well written instructions, a nice quick easy project that can show you something local and relevant.
Living in Southampton it only took a paltry couple of metres sea level rise to inundate much of the city - looks like my oceanography degree will come in handy!
Will said...
Cool! For global coverage, you can use Google Earth's Image Overlay feature: pick a blue image, view its properties, turn down the opacity, go to the Location tab, and set North/East/South/West to 90, 180, -90, -180. Unfortunately there are fewer options to set the altitude of the image overlay.
I'd be interested in reading more details about posts and your way around the surface flicker.
redleeder said...
Cheers Rich, i've just finished reading the Book of Dave and wanted to do exactly what you have done here!
Your instructions were perfect - I created the artificial sea across west and north London and saw the island of Ham miraculously appear!
...looking at the 3D plane view I would say that the "Sentrul Stac" of the book is the BT Telecom Tower. What did you think?
Many thanks again for saving me several hours of head-scratching!
redleeder said...
Rich, you are The Geezer!
I've just finished reading the Book of Dave and was wondering myself about the locations, and how realistic the map and directions were.
I found your post on google and followed your instruction... and there before my eyes emerged the island of Ham - exactly as drawn in the book's map [I wonder if Will Self and the illustrator were doing something similar?].
From my own time living near Highgate I remember that the most distinctive feature on the skyline at night [much closer than the City] was the BT Telecom Tower - which with it's irregular top section, and smooth round sides - would make a perfect place for a seagull colony.
Thanks again guv, for saving me many hours of painful head-scratching.
belfor said...
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{
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"edu_score": 3.546875,
"fasttext_score": 0.041136980056762695,
"language": "en",
"language_score": 0.9329099655151367,
"url": "http://googleearthdesign.blogspot.com/2011/01/flood-simulation-howto.html"
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February 26, 2017
Homework Help: econ.
Posted by fred on Saturday, June 11, 2011 at 5:00am.
2. A company is considering building a bridge across a river. The bridge would cost $2 million to build and nothing to maintain. The following table shows the company¡¯s anticipated demand over the lifetime of the bridge:
Price per crossing ($) 8 7 6 5 4 3 2 1 0
Number of crossings (¡®000) 0 100 200 300 400 500 600 700 800
a. If the company were to build the bridge, what would be its profit-maximizing price? Would that be the efficient level of output? Why or why not?
b. If the company is interested in maximizing profit, should it build the bridge? What would be its profit or loss?
c. If the government were to build the bridge, what price should it charge?
d. Should the government build the bridge? Explain your answer.
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<urn:uuid:4060593c-b677-4837-8c39-6cc31fe5edfa>
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{
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"edu_int_score": 4,
"edu_score": 3.609375,
"fasttext_score": 0.5696680545806885,
"language": "en",
"language_score": 0.9373274445533752,
"url": "http://www.jiskha.com/display.cgi?id=1307782815"
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The spread of points in one dimension is easy to calculate and to visualize, but the spread of points in two (or more) dimensions is less simple. Instead of familiar error bars, standard deviational ellipses (SDEs) represent the standard deviation along both axes simultaneously. The result is similar to a contour line that traces the edge of one standard deviation, as on a topographic map or an isochore map. The calculation of a standard deviational ellipse can be tricky, because the axes along which the ellipse falls may be rotated from the original source axes.
Figure 4.14 from CrimeStat III -- points representing locations of car thefts in Baltimore, with an ellipse indicating the highest density of thefts.
The standard deviational ellipse algorithm is described here and here, and it was implemented in aspace, an R library for geographic visualization work developed by Randy Bui, Ron N. Buliung, and Tarmo K. Remmel. The SDEs are calculated by calc_sde and are visualized by plot_sde. (The people who are most interested in multi-dimensional standard deviations seem to be geographers visualizing point data; an example of visualizing auto theft in Baltimore appears at right.)
The aspace SDE implementation is a very useful implementation. I’m going to talk about implementing three extensions to it:
• Giving better example code for how to use the package.
• Fixing a bug in which the ellipse is often incorrectly rotated by 90 degrees. [This has been fixed by the authors in aspace 3.2, following contact from me.]
• Adding a feature that shows more than one standard deviations.
This post addresses each in turn.
More Thorough Example Usage Code for aspace::plot_sde
plot_sde doesn’t take the result of calc_sde as a parameter, and its documentation doesn’t indicate how R knows which SDE to draw. To draw an SDE, run plot_sde immediately after calc_sde. R uses an implicit object hidden from the user to pass data. A better usage example is:
# Example aspace::calc_sde and aspace::plot_sde Code
# Create the data and rotate it
x = rnorm(100, mean = 10, sd=2)
y = rnorm(100, mean = 10, sd=4)
t = -pi/4 # Illustrates normal case (rotated to right from vertical)
#t = pi/4 # Illustrates the bug described below (rotated to left from vertical)
transmat = matrix(c(cos(t),-sin(t),sin(t),cos(t)),nrow=2,byrow=TRUE)
pts = t(transmat %*% t(cbind(x,y)))
# Create the plot but don't show the markers
plot(pts, xlab="", ylab="", asp=1, axes=FALSE, main="Sample Data", type="n")
# Calculate and plot the first standard deviational ellipse on the existing plot
plot_sde(plotnew=FALSE, plotcentre=FALSE, centre.col="red", centre.pch="1", sde.col="red",sde.lwd=1,titletxt="", plotpoints=TRUE,points.col="black")
# Label the centroid, explicitly using the hidden r.SDE object that was used in plot_sde
text(r.SDE$CENTRE.x, r.SDE$CENTRE.y, "+", col="red")
The above code will plot the data without axes, layering the SDE ellipse on top of a plot that does not display data markers (as illustrated at below right).
Original ellipse is off by 90 degrees from the scattered points; improved ellipse is not.
Correct Visualization Regardless of Major Axis
14 August 2012: This has been fixed by the authors in aspace 3.2 following contact from me.
The aspace 3.0 calc_sde code (accessible by typing the function name without parentheses at the R prompt) includes the lines:
if (tantheta < 0) {
theta <- 90 - atan_d(abs(tantheta))
} else {
theta <- atan_d(tantheta)
This code seems to aim to ensure that theta is a positive number — but the first line doesn’t ensure that. Instead it causes negative rotations to end up at 90 degrees to where they should be (as in the illustration at right). Instead that first if-clause could be:
if (tantheta < 0) {
theta <- 180 - atan_d(abs(tantheta))
} else {
theta <- atan_d(tantheta)
This code is one of multiple options that fixes the off-by-90-degrees issue.
Display of Multiple Standard Deviations
The aspace 3.0 calc_sde code only will only trace an ellipse of one standard deviation in each direction. To change this, add a multiplicative factor to sigmax and sigmay immediately before (or immediately after) the following lines:
if (sigmax > sigmay) {
Major <- "SigmaX"
Minor <- "SigmaY"
else {
Major <- "SigmaY"
Minor <- "SigmaX"
For instance, to calculate (and therefore plot) two standard deviations around the centroid, add in the lines:
These lines double the length of the single-standard-deviation major and minor axes.
Updated 2012-08-14.
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"edu_score": 3.515625,
"fasttext_score": 0.03607147932052612,
"language": "en",
"language_score": 0.8312273025512695,
"url": "http://www.pamelatoman.net/blog/tag/standard-deviational-ellipses/"
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|
The Concept of Queen Mary
Queen Mary
Cunard’s legendary Queen Mary had a troubled start. Designed in the 1920’s as an eventual replacement for Mauretania, the ship’s original plans called for a liner similar to Aquitania. The ship’s dimensions called for a liner over 1,000 ft long and 81,000 tons!
On 31 January 1931 the keel was laid on Hull 534 at the John Brown shipyard in Clydebank. Construction of the ship progressed well and the launch was scheduled for May 1932.
However, on 11 December 1931 Cunard announced that work on the ship was to be suspended, due to the crippling effect of the Great Depression. Cunard and the British shipping industry had been hit hard by the lack of travellers, and Cunard were forced to lay off the John Brown workforce indefinitely.
White Star Line was also facing economic ruin. The smaller line had approached the British Government for assistance. Cunard, desperate to complete Hull 534, also approached the government for assistance.
The British Government were particularly concerned about the state of the British shipping industry. Germany, Italy and France had all eclipsed Cunard and White Star Line with tonnage including the legendary Bremen, Rex and Normandie.
In December 1933 a government brokered deal was reached whereby the two companies merged to form Cunard-White Star Line. In return, the government lent the company £9.5 million. This allowed Cunard-White Star to recommence construction on Hull 534 and also plan a running mate. In April 1934 work began again on the ship.
Early Years
With the workforce back aboard the ship, work progressed quickly. It was completed by August 1934 and the ship was launched as RMS Queen Mary on 26 September by HM. Queen Mary.
The ship’s fit out saw a magnificent art-deco interior installed aboard the liner. By March 1936 Queen Mary set sail for her sea trials.
Queen Mary’s maiden voyage departed on 27 May 1936; sailing on the Southampton to New York (via Cherbourg) service.
Despite Cunard declaring that the Queen Mary was not designed to race against France’s Normandie, expectations that the ship would try to break speed records on its maiden voyage were strong among those on both sides of the Atlantic.
However, in the final days of what would have been a record crossing, a thick fog descended upon the ship and Queen Mary was slowed, making a record attempt impossible.
In August, Queen Mary undertook a record breaking crossing from Bishop’s Rock to Ambrose Lighthouse, capturing the Blue Riband for the first time from Normandie.
Normandie reclaimed the speed record from Queen Mary however in August 1938 Queen Mary regained set new records for both the eastbound and westbound crossings; this time holding the record until 1952.
Queen Mary made her last peacetime voyage from Southampton on 30 August 1939. Upon arrival in New York, the ship was berthed until the end of the year while the war escalated and the Admiralty decided what role the ship would play.
Queen Mary’s War Service
Having been joined in New York by Normandie, Mauretania and the new Queen Elizabeth, for a brief period four of the world’s largest liners sat idle together in the harbour.
Queen Mary
However by March 1940 Queen Mary was called into military service. She sailed from New York bound for Sydney, Australia. Upon her arrival she was sent to the Cockatoo Drydock on Cockatoo Island, and work commenced to convert the ship into a troop carrier. Queen Mary’s luxury fittings and interior were removed and stored. In their place, bunks and hammocks were installed.
Small caliber guns were fitted on the ship to offer protection against air attack, however the Queen Mary’s main protection was her speed. To that end, the liner was ordered to sail at high speed when carrying troops to avoid danger from enemy shipping.
On 4 May 1940, Queen Mary departed Sydney with 5,000 troops of the Australian Imperial Force on board, bound for the Clyde. After operating on this route, and various others, Queen Mary concentrated on voyages between Australian ports, Singapore and Suez.
Once American entered the war on the side of the allies, Queen Mary’s trooping capacity was increased to 10,000+, with her new role as a mass transport of troops on the North Atlantic. On this service, Queen Mary carried the most people ever transported by a ship; 16,082 in one voyage!
On 2 October, while Queen Mary was steaming at 28-knots in a zigzag pattern the ship collided with her escort the HMS Curacao. The accident resulted in the smaller escort being cut in two, and sinking. Queen Mary’s hull was damaged, and between October and December 1942 Queen Mary was repaired at Boston.
At the end of the warm Queen Mary was used in the urgent and time consuming task of repatriating thousands of servicemen. Following this duty, the ship was used on the war bride service, being employed in this capacity from January to September 1946.
Passenger Service
Queen Mary was returned to Cunard on 27 September 1946, having sailed some 600,000 miles; carrying 800,000 people. Following an extensive refurbishment, the ship was returned to Cunard service; having had her passenger capacity adjusted to carry 711 first class, 707 cabin class and 577 tourist class passengers.
Queen Mary’s first post-war voyage departed on 31 July 1947; sailing from Southampton to New York. Later that year, industrial action hindered the service however despite this Queen Mary remained a popular liner during the 1950’s. Along with Queen Elizabeth, the liner was able to complete the world’s first and only two-ship weekly transatlantic service.
In 1952, Queen Mary lost her speed record to the SS United States. The American’s had seen the success of the large Cunard liners during World War II, and with the Cold War now in full swing, the US Government supported the United States Lines in building what remains the world’s fastest ocean liner.
Despite this, Cunard’s Queen Mary remained popular. Business was good for most of the 1950’s – however air travel was becoming increasingly dominant.
In March 1958 Queen Mary was fitted with Denny-Brown stabilisers. Originally trailed aboard the smaller Cunard liner Media, these stabilisers greatly helped Queen Mary’s stability.
In 1958, Boeing’s 707 jet made its first commercial service across the atlantic. This signalled the beginning of the end of the transatlantic liner. By the beginning of the 1960’s there was speculation that Queen Mary would retire. In December 1963 Queen Mary made her first cruise, and this use became an increasingly important part of the ship’s career.
However Queen Mary was not well suited for cruising. Her art-deco interiors were by now a dated style; while any benefits from cruising were undermined by the Seamans Strike of 1966. The strike cost Cunard £4 million. This made retaining the loss making Queen Mary impossible. Sold to Long Beach California, Queen Mary sailed on her last transatlantic crossing on 16 September 1967. She then undertook her longest ever peacetime voyage; sailing around Cape Horn before docking in Long Beach.
Today Queen Mary operates as a floating hotel, conference centre and museum. She is berthed near the new Carnival Cruise Line terminal and is often used as a hotel by guests travelling aboard a Carnival Cruise Liner.
Image source: Wikimedia Commons.
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"fasttext_score": 0.029313325881958008,
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"url": "http://chriscunard.com/queen-mary/queen-mary-history/"
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Teaching the Hydraulics and Pneumatics Unit to Children
Microsoft Office document icon Pneumatics_and_Hydraulics_Module.doc72.5 KB
Hydraulics and Pneumatics are great topics to teach children. First of all both words sound very impressive and when the children learn these words they will sound very important and knowledgeble if they use them. Also, hydraulics and pneumatics are used in many machines and in many everyday applications, therefore it is easy to show the importance of understanding these topics. One can easily show and explain the difference between hydraulics and pneumatics - a great "Compare and Contrast" analysis. Thirdly, there are many fun and impressive experiments that can be done with hydraulics and pneumatics in a very inexpensive way, with very accessible materials. And finally, since hydraulics and pneumatics is so useful, there can be multiple projects that children can actually build themselves. Thus weaker students and stronger science students can both do projects, yet with differing complexity.
Here are some of the techniques I use in order to teach hydraulics and pneumatics to children:
1. FLUID PRESSURE: Hydraulics and Pneumatics for me is a culmination of a study of Fluids. Therefore, before I talk about hydraulics and pneumatics, I must talk about Fluid Pressure.
I start with a discussion of Pressure in general, it's formula, the units.
Pressure: The measure of the force acting perpendicular to a unit area.
(Here I demonstrate pushing with finger compared to pushing with a whole hand against a wall, book, child volunteer from the class, with the same force. Since the children already have a good understanding of force, they can see that pressure is very similar to force, but spread out over an area - therefore the smaller the area it's spread out, the more concentrated the force is, and vice versa.)
Formula: P = F/A
(Even though children might not be ready to understand formulas yet, I like to introduce formulas to even the youngest children, so they start to see the relevance of math, and formulas in science.
I explain that the formula pretty much means the same thing as the definition above - Force spread over an area. This is useless for the weaker students, but will get the stronger science students thinking about the relationship between formulas and definitions... excellent for planting the seed for future physicists and engineers.)
Units: (from the formula N/m2) or Pa (pascals), kPa (kilopascals), 1kPa = 1000Pa
(I definitely talk about units whenever I introduce a new concept. I talk about where the units come from - starting with the formula: Force over area, force is measured in Newtons, area is measured in m squared. This is a great way to engage students, asking them for answers, leading them to the solution. Then I mention that instead of using two units, scientists decided to invent one unit to denote this relationship: Pa - after a well known scientist Pascal. And another great discussion point comes up when I talk about kPa and how it's related, just like g and kg or m and km. Lots of stuff to talk about here. Sometimes I even get the students to do research on who Pascal was, and why the pressure unit was named after him).
If force increases --> pressure increases
If area increases --> pressure decreases
(These statements are critical to mention and discuss in detail. This can be explained again with the pushing of a student with a whole hand compared to a finger. Or even talking about or demonstrating walking barefoot on a plank of 100 nails compared to walking onto one nail. Making such a plank of wood with many nails sticking out of it and keeping it for future classes is a good idea and when used to demonstrate this concept is very visual as well as dramatic - a good way to keep students engaged and to remember this concept. You can also use the example and demonstrate walking on many eggs at once compared to walking on just one egg. If you have access to an lcd projector in the classroom, there are many YouTube videos showing people walking on eggs, and not breaking them (here's a link to a good one: http://www.youtube.com/watch?v=LszleCrvFyQ )If you don't want to spend a whole class on this concept, you can just quickly talk about some of these examples, getting some input from students, and continue.)
Next I talk about pressure of fluids (fluids, by the way, are materials that flow like liquids and gases)
Fluid Pressure: Exerted in all directions equally
(I make sure to use many diagrams and as few words as possible in my notes. Students learn, understand and remember pictures so much better than a sentence.)
Confined Fluids: - any fluid in a closed system
- the fluids can move around within the system, but cannot leave or enter the system
examples: - blood moving through the body
- air moving in an air matterass
(A discussion of confined fluids is essential before starting a discussion of hydraulics and pneumatics. Also as many examples as possible makes the concepts applicable and less foreign to the children. Examples taken from the students themselves are even better, as the learning is less passive and more active at this point.)
Gases Liquids
- are very compressible - are not compressible
- because the gas particles are very spread out - the particles in a liquid are not as spread out as in a gas
(Here I would call on a demonstration or experiment of this. You could do many things; some examples: take a syringe, fill it with air, and then cover the open end with your finger. Show that the air can be compressed by pushing down on the plunger. Let the students do this, so that they see it is not some sort of trick. Then fill in the syringe with water.
Again covering the end with your finger, show that now you cannot compress the water with all your might. Try very very hard to make sure they see your effort. Get students to replicate this. This also makes for a great whole class experiment / activity. Make sure you think of some interesting questions and then get the students to experiment / fool around with syringes filled with air and water. Watch out, because when I did this, lots of the time, the students ended up having a water fight with the syringes - not really a big deal if contained to the classroom though)
Examples of questions for a lab:
If you fill in the syringe with 20mL of air, to what volume can you compress it?
If you fill in the syringe with 20mL of water, to what volume can you compress it?
What is the difference between compressing air and water?
Attach two syringes with some tubing with air in the confined system. What happens when you press on the plunger?
Attach two syringes with some tubing with water in the confined system. What happens when you press on the plunger?
Attach three syringes (two of the same size, and one larger) with some tubing and a T valve. What happens when you press on one plunger?
Attach three syringes with some tubing and a one way valve. What happens when you press on one plunger?
(Lots of things happening here. The students start getting a feel for hydraulics and pneumatics. They realize that in hydraulics there is no delay, and the force is passed on instantly to the other syringe, while in pneumatics there is a delay of action because of the compressiblity of gases. Then you can introduce the valves - T intersection, one way valve, etc.
This shows the children different ways of controlling the flow of fluids. Make sure you relate the valves to something they are familiar with, like a tap in a bathtub, etc.)
2. HYDRAULICS AND PNEUMATICS: Once the children understand pressure and get their feet wet with syringes and pressure of fluids (gases compared with liquids, etc.) they are ready for hydraulics and pneumatics.
I jump right in by making a huge table, comparing Hydraulics to Pneumatics:
(As I write this table, and get the children to copy it, I have a class discussion every step of the way, along with demonstrations of
hydraulics: the two syringes with water inside them- when you push on one plunger, the other plunger moves... this can be used to lift an object - the basic principle of hydraulics!
and pneumatics: two syringes joined together with some tubing, with air inside them. When press down on one syringe, the other piston lifts.
By this point, student really start to understand what hydraulics and pneumatics is about and how it can be used.)
3. HYDRAULICS LIFT: This is an important part of hydraulics. There is many explanations online of the hydraulics lift, how it works and pictures of it, so I won't get into that (check out http://hyperphysics.phy-astr.gsu.edu/Hbase/pasc.html).
But it is important to explain to the children that a small force can be used to lift a large object (such as a car) - of course there is a trade-off: the large object goes up just a very small distance, while the force acting on the smaller piston, using a smaller force, has to go through a larger distance. This is why hydraulics is so useful. I would spend at least a class, if not two to go over this concept and do some experiments with it (two syringes, one small, one large connected with some tubing, along with some weights, small and large, etc.
4. PROJECT: I then jump in here with a project, where the students must build a hydraulic or pneumatic model of a machine. See the attached outline and some of the resulting possible projects: http://www.nucleuslearning.com/content/hydraulics-and-pneumatics-projects.
If you want to get a start up kit for a demo or more help, try some of these:
Submitted by bogusia on Thu, 10/09/2008 - 19:14
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01/22/2013 09:40:51
Notes from the Back Row: "Engineering with Impact"
If you hit something hard enough, it will break, and the consequences can be catastrophic. A space rock roughly the size of Pasadena killed the dinosaurs when it hit the Earth at about 45,000 miles per hour, but even something as small as a bird hitting a turbine blade can bring down an airplane. The damage occurs in the blink of an eye as unimaginable pressures are fleetingly focused on the hapless chunk of rock or metal. The key to survival is to disperse those forces. But how? Caltech professor Ravi Ravichandran is trying to find out.
Guruswami "Ravi" Ravichandran is the John E. Goode, Jr., Professor of Aerospace and professor of mechanical engineering and the director of the Graduate Aerospace Laboratories at Caltech. His PhD thesis on the fracture dynamics of metals under extreme impacts, written at Brown University in 1986, remains one of the classic papers in the field.
At Caltech, Ravichandran studies impacts that pack a wallop of up to a million times the pressure of Earth's atmosphere. Such extreme pressures are actually quite mundane: a head-on collision at 65 miles per hour exerts a force of some 7,000 atmospheres during the millisecond that the vehicles' steel frames buckle. (By contrast, the pressure at the bottom of the Mariana Trench in the western Pacific, the deepest point in the world's oceans, is a mere 1,000 atmospheres.) In a typical experiment, a reconditioned naval gun from World War II shoots an aluminum projectile at a copper plate, compressing it by as much as 30 percent for a millionth of a second. Meanwhile, a laser "camera" records the ripples created by the projectile's kinetic energy as it turns into pressure waves within the copper plate.
The best way we know to dissipate these waves is to pass them through alternating layers of very stiff and very elastic materials. This is the principle behind body armor and bulletproof glass, as Ravichandran vividly demonstrated during his talk by showing a video clip produced by an armored-car company. In the clip, the company's CEO stood behind a bulletproof windshield while his assistant peppered it with three rounds from an AK-47. Spiderwebs of cracks formed in the inner layer of glass and license-plate-sized fragments of the outer layer were blasted free, but the layer of polymer sandwiched between the glass sheets stopped the slugs. If one layer of elastic is good, more layers should be even better. The logical extreme—an infinite number of layers—presents certain manufacturing challenges, so "we're extending this idea of layered media into particulate composites in order to make realistic engineering materials for shock-protection applications," Ravichandran says. Think high-tech sandbags, in other words.
"Engineering with Impact" is available for download in HD from Caltech on iTunesU. (Episode 13)
Written by Douglas Smith
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Littoral and benthic zone, Biology
Littoral and Benthic Zone
Littoral Zone
This is the shallow water zone, near the shore, where light penetrates to the bottom. Rooted plants can grow only in this region.
Benthic Zone
This forms the floor of the lake and underlies the littoral and limnetic zone.
Posted Date: 1/19/2013 4:50:31 AM | Location : United States
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This passage will test your knowledge on Newton's laws and equilibrium .
A renal calculus, otherwise known as a kidney stone, is a solid formation of urinary minerals found in the urinary system. Kidney stones often pass through the urinary tract undetected, although they begin to obstruct the pathway when they grow to 3, space, m, m in size or greater. This process involves both walls of the ureter applying force on the kidney stone until it no longer moves. In these instances, they may cause pain and, in extreme cases, can require surgery.
A patient has a kidney stone of mass 0, point, 0015, space, k, g. The kidney stone is moving at a constant velocity from the kidney to the bladder via a path through the ureter tube as seen below.
Figure 1. A kidney stone passing from the kidney, through the ureter, towards the bladder.
Assume that the only significant forces acting on the kidney stone in this case are as follows:
Force F, start subscript, 1, end subscript: The frictional force between the stone and the sides of the ureter
Force F, start subscript, 2, end subscript: The force pushing the kidney stone towards the bladder, caused by pressure behind the kidney stone
Note: Assume that the force of gravity on the kidney stone can be ignored since it is so small compared to the size of Force 1 and Force 2.
During a certain time interval, the kidney stone is moving toward the bladder with constant velocity. How must the magnitude of Force 2 compare with the magnitude of Force 1 during this time?
Please choose from one of the following options.
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"url": "https://www.khanacademy.org/test-prep/mcat/physical-sciences-practice/physical-sciences-practice-tut/e/newton-s-laws-and-equilibrium---passage-1"
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Hess, Germain Henri
Germain Henri Hess (1802-1850), a Swiss chemist and pioneer in the field of thermochemistry. Hess' Law states that if a chemical reaction is carried out in a series of steps, the change in enthalpy for the reaction will be equal to the sum of the enthalpy changes for the individual steps. The experiments that led to Hess’ Law were important because they wed thermodynamics and chemistry, showing that that the law of conservation of energy applied to chemical changes as well as to physical changes. In addition, these experiments suggested that chemical reactions, like physical processes, had an inherent spontaneous direction in which entropy was increased.
Cleveland, C. (2006). Hess, Germain Henri. Retrieved from http://www.eoearth.org/view/article/153494
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Collared plover
From Wikipedia, the free encyclopedia
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Collared plover
Charadrius collaris.jpg
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Subclass: Neornithes
Order: Charadriiformes
Suborder: Charadrii
Family: Charadriidae
Genus: Charadrius
Species: C. collaris
Binomial name
Charadrius collaris
(Vieillot, 1818)
The collared plover (Charadrius collaris) is a small shorebird in the plover family, Charadriidae. It lives along coasts and riverbanks of the tropical to temperate Americas, from central Mexico south to Chile and Argentina.
This small plover is 18 centimetres (7.1 in) long and weighs 35 grams (1.2 oz). Its upperparts are brown and the underparts white in all plumages. Adults have a black breast band. The male has a white forehead, bordered above by a black frontal bar, and below by a black stripe from the bill to the eye. The midcrown and nape are chestnut and the legs are yellow. In flight, the flight feathers are dark with a white wing bar, and the tail shows white sides.
The female collared plover is usually very similar to the male, but some individuals can be sexed by a brown tinge to the black areas. Immature birds lack any black on the head, and the breast band is replaced by brown patches on each side of the chest. The flight call is a sharp metallic pip.
Two sympatric Charadrius species are very similar: The snowy plover is similar in size and structure to this species, but is paler above, has dark legs, and never has a complete breastband. semipalmated plovers are larger, thicker-billed, and has a pale collar. Ironically, it is the lack of a pale collar which gives the collared plover its English language and scientific names.
The collared plover is found on sandy coasts, estuarine mud, inland riverbanks and open sandy savannas. It breeds from Mexico south through Central America and most of South America. It also occurs on some of the southern Caribbean islands, and both Trinidad and Tobago. It appears to be mainly sedentary, although there is some evidence for limited seasonal movements. Collared plovers feed on insects and other invertebrates, which are obtained by a run-and-pause technique, rather than the steady probing of some other wader groups. This species is not particularly gregarious, and seldom forms flocks. It is usually very wary.
The timing of breeding activity varies depending on location: November to December in western Mexico,[2] March to June in Costa Rica,[3] January in Venezuela, and March in the lowlands of Ecuador. The male's courtship display involves fluffing out his breast feathers and running after the female; the species has no known aerial display.[2] The nest is a bare ground scrape well above the tide or flood line on coasts and river shores or islands, or inland, often next to low cover, such as tufts of grass. The clutch is two pale buff eggs, spotted with brown.[3] Like many ground-nesting species, adults perform a broken-wing display to lure presumed threats away from their nest and young.[4]
1. ^ BirdLife International (2012). "Charadrius collaris". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
2. ^ a b Hayman, Peter; Marchant, John; Prater, Tony (1986). Shorebirds: an identification guide to the waders of the world. Boston: Houghton Mifflin. p. 296. ISBN 0-395-60237-8.
3. ^ a b Stiles, F. Gary; Skutch, Alexander Frank (1989). A guide to the birds of Costa Rica. Ithaca: Comstock. p. 139. ISBN 0-8014-9600-4.
4. ^ Greeney, Harold F.; Gelis, Rudolphe A.; White, Richard (2004). "Notes on breeding birds from an Ecuadorian lowland forest" (PDF). Bulletin of the British Ornithologists' Club 124 (1): 28–37.
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CDC Home
Posted January 20, 2009
Epi Curve
This outbreak can be visually described with a chart showing the number of persons who became ill each day. This chart is called an epi curve. Please see the Timeline for Reporting of Salmonella Cases for more details on the reporting process.
Figure 1. Date of illness onset, by day
Infections with the outbreak strain of Salmonella Typhimurium, by date of illness onset
Interpretation of Epidemic Curves During an Active Outbreak
The epidemic curve (epi curve) shows progression of an outbreak over time. The horizontal axis represents the date when a person became ill, also called the date of onset . The vertical axis is the number of persons who became ill on each date. These are updated as new data come in, and thus are subject to change. The epi curve is complex and incomplete. Several issues are important in understanding it.
• There is an inherent delay between the date that an illness starts, and the date that the case is reported to public health authorities. It typically takes 2-3 weeks for Salmonella infections. That means that someone who got sick last week is very unlikely to have been reported yet, and someone who got sick three weeks ago may just be reported now. Please see the Salmonella Outbreak Investigations:Timeline for Reporting Cases.
« Read the full Outbreak Investigation
Contact Us:
• Centers for Disease Control and Prevention
1600 Clifton Rd
Atlanta, GA 30333
• 800-CDC-INFO
TTY: (888) 232-6348
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Papyrus Making 101: rediscovering the craft of making ancient paper
An Introduction to Ancient Seals.
In antiquity people felt keen anxieties regarding document security just as we do in the modern age. Various methods of storing and sealing documents were employed to restrict access and ensure authenticity. Documents treated in such a manner would include private letters, deeds to property, marriage contracts and receipts held for taxes rendered. Sealings were used to indicate that the proper authorities had authenticated the validity of the contracts or receipts, and could also indicate that others had borne witness to the transactions.
One particular method of sealing documents is particularly interesting. This is the practice of sealing what are known as double documents. “Double documents” typically consist of two separate blocks of text. One block explicitly lays out the terms of the contract (this portion is known as the scriptura exterior), and the other is either a complete reiteration or a synopsis of the contract (this portion is known as the scriptura interior). The scriptura interior is then rolled, a hole is punched in the papyrus between the two blocks of text and a strand of papyrus is passed through the document so that a clay seal can be stamped over it. The scriptura interior of the contract is now sealed so that it cannot be read without cutting the strand of papyrus that binds it, while the scriptura exterior may be consulted at will. This practice prevents any of the parties involved from editing important aspects of the document, such as the amount of money owed or the number of acres sold.
A number of sealed papyri at the University of Michigan have recently been opened. These are similar to the double documents as described above, but they preserve only scant information in the scriptura interior that is unlikely to be the synopsis of a contract. It is possible that the scriptura interior of these papyri only include the calculations that were vital to the contract, such as monetary amounts and units of property. In such a case these documents may prove to have been notary contracts. Full publication of these documents will disclose their actual contents.
The measures taken by Leyla Lau-Lamb, senior conservator at the University of Michigan, will make future study of these documents possible, and facilitate a greater understanding of the practice of sealing contractual documents in antiquity.
To learn more about sealing practices in Greco-Roman Egypt, please consult Katelijn Vandorpe’s “Seals in and on the Papyri of Egypt.” Archives et Sceaux du Monde Hellenistique, Athens: Ecole Française d'Athènes, 1996: 231-291.
Dr. Vandorpe has also created a website dealing with this topic that can be accessed at
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From Wikipedia, the free encyclopedia
Jump to: navigation, search
Incised means cut, particularly with a "V" shape. It is a term found in a number of disciplines.
Schematic of a river incising downward through bedrock (gray). Process begins with the top image.
In geomorphology, the term Incised refers to when a river has cut downward through its riverbed. The river may have been incising through sediment or bedrock. The river begins at one elevation and incises downward through its bed while leaving its floodplain behind (higher). Although, it is possible for the floodplain to be lowered at the same time. Examples include Mobile Bay along the Gulf of Mexico.
In medicine an incised wound is one made with a cutting instrument, often a deep wound. (See incision)
An incised structure is one with a deep "V" shaped notch, often used to refer to the outline of a leaf, or the membranes on a fish's fin.
Archaeology and the Plastic Arts[edit]
Incised in archaeology and the plastic arts refers to cutting into the surface of a medium, for example stone or wood. It often refers to the use of a "V" shaped tool to carve out the design. Writing carved into stone tablets or columns is often referred to as "incised".
Incised is a sans-serif typeface.
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Definition from Wiktionary, the free dictionary
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Alternative forms[edit]
Etymology 1[edit]
From Middle English tocomen (to come, arrive, happen), from Old English tōcuman (to come, arrive), from Proto-Germanic *tō (to), *kwemaną (to come), equivalent to to- + come. Cognate with Dutch toekomen (to forward, deserve, merit, suffice), German zukommen (to come on, benefit, become).
tae tocome (third-person singular simple present tocomes, present participle tocomin, simple past tocam, past participle tocomen or tocomet)
1. (intransitive) To arrive.
2. (of a letter, package, etc.) To arrive at, reach a destination; come to a person's attention.
3. (of an event) To happen; be about to happen.
4. (transitive) To encounter
Derived terms[edit]
Etymology 2[edit]
From Middle English to-come, from Old English tōcyme (coming, advent, arrival).
tocome (plural tocomes)
1. A future period of time.
in tocum
2. An approach; onset.
3. An entrance.
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In Dante's The Divine Comedy, written in the late 1200s, a character named Ulysses told of a voyage beyond the Pillars of Hercules—two peaks at the western entrance to the Mediterranean. His goal was to explore the unknown world, and he and his crew sailed westward for five months. Just as they sighted land, a fierce storm destroyed their ship and killed them.
In the literature of the Middle Ages, Ulysses was often portrayed as a liar and a rogue. In his poem "The Rape of Lucrèce," Shakespeare referred to "sly Ulysses." In the mid-1800s, Alfred, Lord Tennyson portrayed the hero's final years in his poem Ulysses.
James Joyce's novel Ulysses, written in 1922, is based on the Odyssey. Each chapter in the novel takes a different episode from Homer's work to document a single hour of a day in Dublin.
See also Odysseus ; Odysseym, The .
User Contributions:
Ulysses - Myth Encyclopedia forum
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Front Zool. 2010; 7: 25.
Published online Sep 10, 2010. doi: 10.1186/1742-9994-7-25
PMCID: PMC2945339
Within the anomuran crustaceans, the Coenobitidae (terrestrial hermit crabs) have succeeded in the transition from an aquatic to a fully terrestrial life style and have developed pronounced terrestrial adaptations [1-3] that, apart from for the larval stages, allow them to permanently inhabit supralitoral areas and small islands of tropical and subtropical maritime regions, and to penetrate long distances inland [4,5]. These crabs are members of the Paguroidea ("hermit crabs"), a taxon, the members of which have evolved the potential to protect the pleon with gastropod shells. The Coenobitidae comprise two genera, where all species display a fully terrestrial life style [6]. These include 15 species of shell-carrying land hermit crabs (the genus Coenobita) and the robber or coconut crab Birgus latro Linnaeus, 1767 (monospecific genus Birgus) that only carries a shell as juvenile. B. latro is the largest living terrestrial arthropod (Fig. (Fig.1)1) with individuals recorded to weigh up to 4 kg and measure 200 mm in carapace width [5,7-10]. This animal is considered a grade T4 terrestrial species [5], still dependent on water for the marine pelagic larvae that spend three to four weeks at sea before migrating to terrestrial habitats. The early juvenile stages that emerge on land carry a shell, but with subsequent growth the thorax and pleon harden for protection as in other Crustacea [10], making the use of gastropod shells superfluous. B. latro is widely distributed on remote tropical islands of the Indian and Pacific Oceans [11-13]. At present its range includes islands off the east coast of Africa near Zanzibar and eastward to the Gambier Islands in the east Pacific. The borders of the tropical zone (latitudes: 23.4°N and 23.4°S) limit their extent to the north and south [10].
Figure 1
Birgus latro on Christmas Island. A-D: Digital photographs of Birgus latro in the rainforest on Christmas Island. Abbreviations: AI, antenna 1 (antennules); AII, antenna 2.
Land-living crustaceans are fascinating animals that have adapted to a number of diverse terrestrial habitats in which they have become highly successful, and in some case the predominant life forms. This has occurred during a very limited time period in an evolutionary perspective. The successful transition from marine to terrestrial life requires a number of physiological adaptations that are important for survival out of water (see reviews [1-3,5,14-16]). B. latro has served as a model in numerous studies of such physiological aspects, for example, gas exchange, salt and water balance, nitrogenous excretion, thermoregulation, molting and reproduction (Morris, Greenaway and their colleagues [17-35]). Living on land also raises new questions regarding the evolution of olfaction, as a transition from sea to land means that molecules need to be detected in gas phase instead of in water solution. Furthermore, the odor stimulus changes from mainly hydrophilic molecules in aqueous solution to mainly hydrophobic in the gaseous phase (review Hansson et al. [36]). Nevertheless, behavioral studies have provided evidence that members of the Coenobitidae are very effective in detecting food from a distance and in responding to airborne odors. In short, they have evolved a sense of distance olfaction that is behaviorally highly relevant [37-39]. Recently it was also shown that brain areas responsible for processing olfactory stimuli are enlarged in Coenobita clypetaus [40] in comparison to other decapods. As for the giant robber crab B. latro, electro-antennographic studies with the well developed first antennae demonstrated the capacity of this organ to detect volatile chemical information (review Hansson et al. [36]). As in other decapod crustaceans [41,42] the olfactory sensory neurons of B. latro are associated with specialized structures on the first pair of antennae, the aesthetascs [37]. Stensmyr et al. [37] demonstrated that the first antenna responded to CO2 and also noted a pronounced response to water vapor. They also tested various other volatile compounds such as dimethyl-disulfide and dimethyl-trisulfide (both emitted from decaying meat), ethyl-hexanoate (pineapple), isoamyl acetate (banana), phenylacetaldehyde (flower fragrance) and gamma-decalactone (coconut). In particular, the tested oligosulfide compounds were detected in minute concentrations [37]. These authors concluded that their experiments on B. latro point to a peripheral olfactory system as sensitive as the most sensitive general odor-detecting olfactory sensory neurons found in insects, and that therefore is well suited to explore the terrestrial olfactory landscape. Because a pioneering study on the brain of B. latro had already suggested the presence of dominating olfactory centers [43], the current study sets out to explore the general brain architecture in this species in more detail with special reference to the central olfactory pathway.
The data presented in this study are drawn from a series of silver-impregnated (Bodian) horizontal sections (compare Sandeman et al. [43]) that served as the basis for a 3 D reconstruction of the brain, a set of triple-labeled immunofluorescence experiments (the neuropeptide allatostatin, synaptic proteins, and nuclei) and an immunolocalization experiment of the neuropeptide SIFamide (see material and methods). A total of four brains were processed for immunohistochemistry. The following color-coded abbreviations identify the markers in the figures:
AST: Allatostatin-like immunoreactivity
NUC: nuclear counter-stain with the HOECHST nuclear dye
SIF: SIFamide-like immunoreactivity
SYN: synapsin immunoreactivity
The study provides description of the brain anatomy with a level of resolution sufficient for the establishment of a general scheme of the B. latro brain (Fig. (Fig.2)2) and for a more detailed description of the lateral and medial protocerebrum, through the deutocerebrum to the tritocerebrum. The sex was determined for all animals studied in the triple-labeling experiments, but sex-specific differences could not be detected. For simplicity, the description of the brain compartments, most of which are bilaterally paired, is limited to only one hemisphere (left side). The data resulting from the morphometric analysis are presented in combination with data by Beltz et al. ([44] see Table. Table.11 and and22).
Figure 2
Schematic drawing of the brain of B. latro (dorsal view), idealized from ca. 40 horizontal silver-stained sections (10 μm) and several immunostained sections of (100 μm) of four animals. Abbreviations: arrows: deutocerebral organ; 5, 6, ...
Table 1
Morphometric analysis of olfactory compartments
Table 2
Morphometric comparative table
Overview of the Birgus latro brain
The brain of B. latro has an approximate size of 4 mm in length and 3 mm in width and its volume amounts to ca. 1.01 × 1010 μm3 or ≈ 10 μl. In Fig. 3A, C, 4A, C, 5A, C, ,6A6A and and6C,6C, a silver-stained series of the brain is represented from dorsal to ventral. In Fig. 3B, D, 4B, D, 5B, D, ,6B6B and and6D,6D, a section series of the triple-labeling experiments of another animal's brain with nuclear counterstains (blue), anti-synapsin (red) and anti-allatostatin (green) immunohistochemistry is shown in corresponding section planes. The entire brain is surrounded by a tissue layer, the sheath, that exhibits unspecific labeling of allatostatin-like immunoreactivity (ASTir; Fig. Fig.3,3, ,4445,5, 6 to the right) and is also heavily labeled in the silver impregnated preparation (Fig. (Fig.3,3, ,4,4, ,5,5, ,66 to the left). From anterior to posterior, the brain is composed of the proto-, deuto- and tritocerebrum. The protocerebrum can be subdivided into an anterior lateral portion consisting of the bilaterally paired optic neuropils, as well as the lateral protocerebrum and the unpaired medial protocerebrum, with e.g. the protocerebral bridge neuropil (PB) and the central body neuropil (CB). More posteriorly, belonging to the deutocerebrum, the olfactory neuropils (ON), the accessory neuropils (AcN), the paired lateral (LAN) and the unpaired median (MAN) antenna I neuropils, and the columnar neuropil (CN) are located and posteriorly adjoined by the tritocerebral antenna II neuropils (AnN; Fig. Fig.2,2, ,3,3, ,4,4, ,5,5, ,6).6). A three-dimensional (3D) reconstruction based on 89 silver impregnated cross sections is presented in Fig. Fig.77 to show the spatial arrangement of these neuropils. The optic neuropils that receive direct visual input from the compound eyes via the optic nerve (ONv) are visible in the most dorsal sections (Fig. (Fig.3,3, ,4),4), and display strong synapsin-immunoreactivity (SYNir). The optic neuropils are, from anterior/distal to posterior/proximal, the lamina (La), the medulla (Me), the lobula (Lo, synonymous with the medulla interna) and the lobula plate (LoP). The optic neuropils are connected to the terminal medulla (TM, synonymous with the medulla terminalis) and the hemiellipsoid neuropil (HN) via the optic tract (OT). These two neuropils together represent the lateral protocerebum. The HN (Fig. (Fig.3,3, ,4,4, ,5,5, ,6,6, ,8D,8D, ,9)9) displays strong SYNir and is associated with the goblet-shaped cell cluster (5) that contains the somata of densely packed interneurons [45]. The olfactory globular tract (OGT) links the deutocerebral olfactory and accessory neuropils (ON, AcN) and the lateral protocerebrum. It contains bundles of axons extending to the ipsilateral protocerebrum and also fibers that cross the midline towards the contralateral protocerebrum, thus forming a median chiasm (X; Fig. Fig.2,2, ,4,4, ,7,7, 10C, D, E). Within the OGT, a further neuropil is present, displaying strong SYNir, the olfactory globular tract neuropil (OGTN; Fig. 4A, C, 10C, D, 11D). The OGT represents the major output pathway of the olfactory system [45-47] being composed of the axons of numerous olfactory projection neurons, which somata are located in a dorsoventrally extending cell cluster (10). The deutocerebral ON is the dominating neuropil within the brain and is targeted by the primary afferents of the olfactory sensory neurons of the first antenna (Ant I; antennule). The ON is tripartite and composed of more than 1300 so-called "olfactory glomeruli" (Fig. (Fig.2,2, ,3,3, ,4,4, ,5,5, ,6,6, 11D, E, F, G,). These structures, which show strong SYNir and ASTir, are arranged radially along the periphery of the ON. The absence of SYNir and the weak ASTir signal shows that the core of the latter is filled with bundles of fibrous material and does not contain any synaptic neuropils. The distinct accessory neuropil (AcN; Fig. Fig.2,2, ,5,5, ,7B,7B, 10A, 11A, C, 12A, B, C, D, G) is located medially to the ON where the OGT enters/exits the ON, close to the median foramen (mF). The AcN is much smaller than the ON and contains numerous spherical glomeruli that show a strong SYNir, but are almost devoid of ASTir (Fig. 12A, B, C). Anterior to the AcN, nuclear labeling reveals at least one, maybe two further compact cell cluster with densely packed nuclei. These (9/11) comprise the somata of local olfactory interneurons [45]. Subgroups of these neurons display both ASTir and SIFamide-like immunoreactivity (SIFir) in their cytoplasm (Fig. 11A, B1, B2, F). Sandeman et al. [45] distinguished between a dorsal (11) and a ventral (9) cell cluster in Astacura, Brachyura and Palinura. A distinct border inside the cluster (9/11) was not visible in B. latro (Fig. 11A, B, C), however, the axons of the interneurons in cell cluster (11) in the macrurans comprise the deutocerebral commissure and, apart from a small number of large olfactory interneurons [48] these project only to the AcN. The deutocerebral commissure is apparently absent in the brain of Birgus latro. Hence, in B. latro the cluster (11) may be very small given the tiny accessory neuropil, or even absent if this class of interneurons is no longer present (see discussion). Anterio-medially to the ON, the medial protocerebrum (mPC) can be subdivided into an anterior (AMPN) and a posterior medial protocerebral neuropil (PMPN). Nevertheless, these neuropils are fused in the dorsal most and ventral most sections, so that a separation is only obvious in the mid horizontal layers. Between the AMPN and the PMPN, an unpaired transverse, spindle-shaped neuropil displays strong ASTir and SYNir. This is the central body neuropil (CB; Fig. Fig.4,4, ,7B,7B, ,10)10) that extends across the midline. Further anteriorly to the AMPN, the protocerebral bridge neuropil (PB; Fig. 3C, D, 4C, D, ,7B,7B, ,10,10, 13A) is visible, showing ASTir and SYNir. The lateral protocerebrum and the AMPN are connected via the protocerebral tract (PT; Fig. Fig.2,2, 3C, D, ,4D),4D), which shows a weak ASTir signal and is located anteriorly to the AMPN. The cell cluster (6), located anteriorly to the AMPN, includes at least four neurons with somata diameters up to 50 μm among hundreds of neuronal somata with diameters of 5-18 μm. Many cells in cluster (6) display strong ASTir (Fig. 4A, C, ,5A,5A, 10C, D) and SIFir (data not shown here). Posteriorly to the PMPN, the paired lateral antenna I neuropils (LAN; Fig. Fig.2,2, ,4,4, ,5,5, ,6B,6B, ,7,7, 10A, D, 11D, 12A, D, 13A, B, C), which receive mechanosensory and non-aesthetasc chemosensory afferents from the ipsilateral first antennae, extend dorsoventrally across the brain. Similar to the LAN, the unpaired median antenna I neuropil (MAN; Fig. Fig.2,2, ,4,4, ,7,7, ,10)10) shows positive immunoreactivity for synapsin, allatostatin and SIFamide. The MAN is located posteriomedially to the PMPN on the midline and is dorsoventrally penetrated by the cerebral artery (CA; Fig. Fig.2,2, ,3,3, ,7,7, ,10,10, 13A). The nuclei of endothelial cells, as labeled by the nuclear marker, are arranged peripherally along the cerebral artery (Fig. 3A, C). The posteriormost neuropil of the brain is the tritocerebral antenna II neuropil (AnN; Fig. Fig.2,2, 3C, D, ,4,4, ,7A,7A, 13A, B, C), which has an ellipsoid shape and displays strong SYNir. The AnN receives the primary input from the second antenna and contains the synaptic fields of the efferent motorneurons of antenna II [45]. Further dorsally, the borders of the mPC, the MAN and the AnN become more indistinct and finally form a fused columnar neuropil (CN; Fig. Fig.2,2, 3A, B, ,7,7, 13A, D) with strong SYNir.
Figure 3
1st part of a dorsal to ventral series of vibratome sections (100 μm) triple labeled for the nuclear marker (NUC; blue), synapsin immunoreactivity (SYN; red) and allatostatin-like immunoreactivity (AST; green) (A and C) and series of silver impregnated ...
Figure 4
Figure 5
3rd part of a dorsal to ventral series of vibratome sections (100 μm) triple labeled for the nuclear counter marker (NUC; blue), synapsin immunoreactivity (SYN; red) and allatostatin-like immunoreactivity (AST; green) (A and C) and series of silver ...
Figure 6
Figure 7
Three dimensional brain reconstruction of Birgus latro. Only the left hemisphere of bilaterally paired neuropils and cell clusters is shown, when viewed from dorsal. The cell clusters shown in A, are left out in B, to display the ventral surface structure ...
Figure 8
The lateral protocerebrum - optic neuropils. A, B: The detailed 3D-reconstruction of the left brain hemisphere is shown from dorsal and ventral (see inserted brain orientations). The corresponding cell clusters (blue) are displayed semitransparently. ...
Figure 9
The hemiellipsoid neuropil and its corresponding cell cluster. A to C: 3-D reconstructions of the hemiellipsoid neuropil (HN) of the left brain hemisphere in different orientations. In A and B the cell cluster 5 and in C the HN is displayed semitransparently, ...
Figure 10
The medial protocerebrum and the olfactory globular tract. A and B: 3-D reconstruction protocerebral, deutocerebral neuropils and the olfactory globular tract in different orientation (see boxed figures). In A and B the cell cluster 6, the MAN, the OGT ...
Figure 11
The deutocerebral olfactory neuropil. A to C: 3D-reconstruction of the olfactory and accessory neuropil in different orientations. In A, the cell clusters are shown semitranparently to visualize the subjacent structures. D to F: Horizontal vibratome section ...
Figure 12
The accessory neuropil and the deutocerebral organ. Histological sections of cell cluster (9/11), the accessory neuropil (AcN) and the deutocerebral organ (DO) in detail. A to C: Horizontal vibratome triple labeled against cell nuclei (NUC; blue), synapsin ...
Figure 13
Posterior Deutocerebrum and Tritocerebrum. A: 3D-reconstruction of the mid-brain from ventral (see box). B: Horizontal vibratome section, triple labeled against cell nuclei (NUC; blue), synapsin (SYN; red) and allatostatin-like (AST; green) immunoreactivity ...
Protocerebrum: The optic neuropils
The most anterior part of the brain is represented by the stacked optic neuropils, the lamina (La), the medulla (Me), the lobula (Lo) and the lobula plate (LoP), which process the primary optic input from the compound eyes. In B. latro, these neuropils are located close to the median part of the brain, whereas in other decapods they are enclosed in the eyestalks (compare [43]). As a consequence, the retinula cell axons that extend from the ommatidia into the lamina and medulla may measure up to 10 mm or more [43]. Immunolocalization of allatostatin and SIFamide reveals differences in the distribution of these neuropeptides. For example, the lamina and the medulla show stronger ASTir than the lobula, whereas the lobula and the medulla display stronger SIFir than the lamina (Fig. (Fig.8).8). The lamina shows weak SYNir, moderate SIFir, and strong ASTir, and is composed of a thin synaptic layer shaped like a cap, which is distally covered by a layer of cell bodies (cell cluster (1), according to Sandeman et al. [45]). The lamina is connected to the medulla by crossing fibers that form the first or outer optic chiasm (OCh). In addition, the ellipsoid medulla possesses multiple nervous connections to different other target structures, namely the lobula, the lobula plate via the optic tract (OT) and also a third connection where fibers display ASTir and bypass the terminal medulla to target the medial protocerebrum (Fig. (Fig.3A,3A, ,8D,8D, 14A). Furthermore, immunohistochemistry in cross sections shows that the medulla has a characteristic organization with retinotopic layers (Fig. 3A, C, 8C, D), similar to the lamina and the lobula. Altogether, three layers can be differentiated in SIFir and ASTir preparations, of which the anteriormost is the most prominent layer. Between the lamina and the medulla, the interconnecting fibers are surrounded by many cell bodies (cell cluster (2), according to Sandeman et al. [45]). The lobula is located posteriorly to the medulla from which it receives retinotopic input via crossed fibers that form the inner optic chiasm (ICh; according to Sztarker et al. [49]; Fig. Fig.2,2, 8C, E, F). As mentioned before, the lobula possesses several parallel arranged layers showing SIFir and weak ASTir. This neuropil is strongly innervated by a group of visual neurons located in an anteriolateral position with regard to the lobula (cell cluster (3) according to Sandeman et al. [45], Fig. 8D, F). The lobula is closely associated with the terminal medulla (TM), so that the optic tract (OT) is quite short. As in previous studies of brachyuran and anomuran decapods [40,49], B. latro in addition to the lamina, the medulla and the lobula, features a fourth optic neuropil, the lobula plate neuropil. This rather small neuropil is interposed between the medulla and the terminal medulla of the lateral protocerebrum and displays SYNir, SIFir and weak ASTir. In the silver impregnated sections, the lobula plate seems to be entirely wrapped by fibers that extend between the medulla and the terminal medulla (Fig. (Fig.2,2, ,8F).8F). From the eyestalk neuropils, various optic pathways proceed to the lateral and medial protocerebrum.
Figure 14
Bypass fibers, the protocerebral bridge neuropil and the central body neuropil showing allatostatin-like immunoreactivity (AST; green). A: Inverted single channel picture of a horizontal vibratome section, allatostatin-like (AST; black) immunoreactivity ...
Protocerebrum: The lateral protocerebrum
Between the optic neuropils, two closely associated neuropils are present, the hemiellipsoid neuropil (HN) and the terminal medulla (TM, medulla terminalis), which together constitute the lateral protocerebrum. As mentioned above, the latter is connected to the optic neuropils via the optic tract. The lobula is an ontogenetic derivative of the TM, and thus also belongs to the lateral protocerebrum [50]. The TM and the HN together form a large sphere of approximately 900 μm in diameter, in which the TM is located more dorsoposteriorly and the HN ventroanteriorly. Posteriorly, the lateral protocerebrum is connected to the medial protocerebrum via the protocerebral tract (PT; Fig. Fig.2,2, 3C, D, ,4D)4D) that includes the OGT that houses ascending fibers from the deutocerebral accessory and olfactory neuropil. In contrast to the HN, the TM is not geometrically arranged [45,51] and shows SYNir, and strong ASTir and SIFir. On the one hand, the medial neuropil regions of the TM are innervated by the lobula plate and the lobula via the optic tract, and on the other hand they receive strong input from the olfactory pathways of the deutocerebrum via the OGT (Fig. (Fig.2).2). In the 3 D reconstruction of the brain, several groups of cell bodies can be seen to be arranged like a ring around the TM (Fig. (Fig.7A,7A, 8A, B). The hemiellipsoid neuropil with an average volume of 1.91 × 108 μm3 (Table. (Table.1),1), has a highly complex type of onionskin-like organization (Fig. 3C, D, ,4,4, ,5,5, ,6,6, ,7,7, ,9),9), with three distinct synaptic layers. Similar to the brain of the coenobitid hermit crab Coenobita clypeatus (Herbst, 1791; Anomura, Coenobitidae; [40]), a near relative of B. latro, these layers of synaptic fields form two inner core neuropils (CO1, CO2) and a peripheral cap neuropil (Cap; Fig. Fig.9),9), which show strong SYNir and SIFir. In addition to few longitudinally extending axons, these layers also contain numerous fibers, progressing transversely in parallel to the anterior margin of the HN (Fig. 9D, G, J). When viewed in horizontal sections, these fibers form a grid-like structure (Fig. 9G, J). The subunits of the dorsally fused HN are ventrally separated by two clear intermediate layers (IL1, IL2; Fig. 9E, F), formed by several parallel axons that are arranged longitudinally. Higher magnification reveals that there are synaptic interconnections between Cap and CO1, and between CO1 and CO2 among the intermediate layers (Fig. 9G, H). Within the SYNir labeled neuropils, several gaps and nuclei appear, belonging presumably to the vasculature. The HN surmounts a large goblet-shaped cell cluster (5) of densely packed, small interneurons and is invaded by their axons from the ventral periphery (Fig. 9A, B, C, D, F). Both TM and HN are strongly innervated by numerous axons of deutocerebral projection neurons, which somata lie in the cell cluster (10) posteriolaterally adjacent to the olfactory neuropil. At the mid level of the horizontal sections, a prominent tract is visible, the olfactory globular tract (OGT; Fig. 4B, D, ,7,7, ,10),10), that, as mentioned above, interconnects the deutocerebral olfactory neuropils with the neuropils of the lateral protocerebrum. Its enormous arms, formed by bundles of the very small diameter axons of the projection neurons with their somata in cell cluster (10), have a diameter up to 160 μm in B. latro. In sections labeled by immunohistochemistry, the OGT appears as a sort of negative print with the markers that we used (Fig. 4A, C). From the olfactory neuropil, the OGT projects in an anterio-medial direction, where it touches its contralateral counterpart and forming a chiasm (X, Fig. 4A, D, 10C, E) slightly dorsal of the CB. As in other decapods [46,51] the nervous fibers emerging from the ON partially bifurcate at the chiasm and ascends towards the ipsilateral as well as to the contralateral protocerebral neuropils inside the eyestalks. There, the OGT inserts posteriorly at the transition between TM and HN and sends branches into both neuropils (Fig. (Fig.2,2, 4C, D). Unfortunately, we could not trace the course of these branches in detail with the methods applied.
Protocerebrum: The medial protocerebrum
The medial protocerebrum (mPC) is medially positioned between the lateral protocerebrum and the deutocerebrum, and encloses the portion of the OGT forming its chiasm. In a few horizontal sections (Fig. 3C, D, ,4),4), the division of the mPC by the central body neuropil (CB) in an anterior part (AMPN) and a posterior part, the posterior medial protocerebrum (PMPN), as mentioned above, becomes visible. The central complex in the protocerebrum is composed of the protocerebral bridge neuropil (PB), an anterior cell cluster (6) and the central body neuropil (CB). As is known from previous studies on Decapoda, the PB and mainly the CB are well equipped with diverse neuroactive substances (e.g. [52,53] and in B. latro shows strong SIFir (not shown) and ASTir (Fig. 3A, C, 4A, C, 10C, D, 14A, B). Most anteriorly, neuronal somata with various diameters (4-40 μm), are housed in the cell cluster (6), which broadens from ventral to dorsal (Fig. (Fig.7A,7A, 10A, B, 13A). Utting and co-workers [53] described at least five different types of neurons within this cell cluster in the crayfish. In B. latro, Many cluster (6) somata and their fibers show strong ASTir (Fig. 3A, C, 4A, C, ,5A,5A, 10C, D). The PB is V-shaped, when viewed in horizontal sections, and its bilateral, symmetrical neuropil compartments fuse at the midline (Fig. (Fig.7B,7B, 10A, B), posteriorly to the cell cluster (6). In further dorsal sections, few parallel transversally arranged fibers with clear ASTir are present, the ends of which point to the visible ends of the bypass fibers (Fig. 14A), that originate from the medulla (Fig. (Fig.8D).8D). These fibers form an additional connection between the optic neuropils and the medial protocerebrum to the OGT and OT, and possibly form a chiasm anterior to the mPC. In addition, bundles of axons from projection neurons of the lateral protocerebrum, ending at the contralateral part of the PMPN, progress anteriorly and ventrally along the CB [53]. The cigar-shaped central body is an unpaired midline neuropil located centrally within the mPC and marks the boundary between the AMPN and the PMPN. In a few sections, it becomes visible by immunohistochemical labeling with ASTir (Fig. (Fig.4A,4A, C, 10D), and it is well detectable in the silver impregnated sections (Fig. 10E, 14C). Several fiber bundles connecting the PB with the CB become visible in silver impregnated sections with higher magnification (asterisks in Fig. 14C). These bundles possibly correspond with the W-, X-, Y- and Z-fiber bundles which have been previously described by Utting and co-workers [53] in the crayfish Cherax destructor. The CB is typically located, slightly ventral to the chiasm of the OGT.
Deutocerebrum: The olfactory neuropils
The most prominent neuropil of the B. latro brain is the olfactory neuropil (ON) with an average volume of 3.75 × 109 μm3, both hemispheres accounting for a percentage of 26.3% of the total neuropil volume (Table. (Table.2).2). The ON receives chemosensory input from olfactory sensory neurons on the ipsilateral first antenna via the antenna I nerve (AINv). Their axons invade the ON from an anterio-ventral direction (data not shown here). Two large cell clusters are associated with the ON, the cell cluster (10) with about 160,000 projection neuron somata, which have an average nuclear diameter of 5.43 μm, and the smaller interneuron cell cluster (9/11), which contains circa 90,000 somata. The most ventral cell bodies in the latter cluster have a smaller diameter than the dorsal ones, which is one of the characteristics to distinguish cells of cluster (9), ventrally from those of cluster (11), dorsally. Subpopulations of cell cluster (9/11) show strong cytoplasmatic ASTir and SIFir (Fig. 12A, B2, F). In silver sections, the transition from cluster (9) to (11) is indistinct. The ON is subdivided into three partitions, an anterio-ventral (ONa), a dorsolateral (ONd) and a posterior-ventral sublobe (ONp; Fig. 11A, B, C, D). Each ON houses ca. 1,300 peripherally arranged olfactory glomeruli on average (Table. (Table.2),2), each showing a typical pattern of strong SYNir and ASTir/SIFir. The olfactory glomeruli combine a conical and columnar shape, and are subdivided into a so-called cap, subcap, and base region. The ASTir and SIFir are stereotypically pronounced in the subcap region (Fig. 11D, E, F, G). The center of the ON is devoid of immunoreactivity except weak ASTir, but in silver stained cross-sections it becomes clear that various fiber bundles, carrying e.g. the major neurites of local interneurons in cluster (9/11) that target the base of the glomeruli, are present. Projection fibers of the OGT and approaching axons of the cell cluster (9/11) penetrate through the median foramen (mF) into the ON, a gap in the radial array of glomeruli. On the opposite margin of the ON, the neurites of cell cluster (10) enter the lobe via the posterior foramen (pF; Fig. Fig.2,2, 11A, D). At the margin of these foramina and at the transition zones between the sublobes (ONa, ONp and ONd), several unstructured, non-glomerular synaptic fields are interspersed between the palisade-like array of olfactory glomeruli. These unstructured neuropils that display SYNir, ASTir and SIFir extend partly into the center of the ON (Roman numerals I-VI, from dorsal clockwise in the right hemisphere and anti-clockwise in the left hemisphere; Fig. Fig.3A,3A, 4A, C, ,5C,5C, ,6A,6A, 11D) and display an identical arrangement in both hemispheres. Six of these unstructured neuropils also occur in C. clypeatus in a corresponding arrangement (called A-F in Harzsch and Hansson [40]). Similar to Coenobita clypeatus [40], strong SYNir, but not any ASTir is present within the OGT posterior to its chiasm (Fig. 4A, C, 10C, D). These synaptic fields belong to the olfactory globular tract neuropil (OGTN). This neuropil contains at least two associated structures more distally, the accessory OGT neuropils (OGTNa). At higher magnification, these neuropils seem to have connections with the PMPN as well as with the deutocerebral MAN and LAN (Fig. 10C). Medially, adjacent to the ON and slightly ventral to the exit of the OGT, a comparatively small neuropil with an average volume of only 500,000 μm3 is present, the accessory neuropil AcN (Fig. (Fig.2,2, ,5,5, 11A, C, 12A, B, C, D, G). This means, it is more than seven hundred times smaller than the ON. Similarly to C. clypeatus [40], the AcN has a spherical shape and is composed of circa 100 almost spherical glomeruli with a diameter of 10-16 μm (Fig. 12A, B, C). These glomeruli show strong SYNir, but weak ASTir and SIFir. In silver-stained cross sections, further anteriorly to the AcN, a small distinct cell cluster adjacent to cell cluster (9/11) is located. Considering the course of the fibers, which target the AcN (Fig. 12G), we suggest it to be a cluster of interneurons. Furthermore, an aggregation of approximately 550 cell somata (Table. (Table.1)1) that form a hollow sphere are located posteriorly and slightly medially of the ON. This is the deutocerebral organ [54] (DO; Fig. Fig.2,2, ,4C,4C, 5A, B, D, 11D, 12D, E; compare reviews [55-58]). Its small cell somata, as labeled with the nuclear marker, have an either spherical or elongated shape.
Deutocerebrum: Other neuropils
Posterior to the mPC and flanked by the bilaterally paired OGTN, the unpaired median antenna I neuropil (MAN; Fig. Fig.4,4, ,7,7, ,10,10, 13A, C) is located. It shows SYNir, strong ASTir and SIFir (not shown) in its center and has an almost spherical shape (Fig. (Fig.2,2, 10A, B, 13A). Ventral to the OGT, the MAN is connected to the PMPN via fibers showing ASTir (Fig. 10D). Further dorsally, distinct neuropil boundaries disappear and the MAN seems to be fused with protocerebral and tritocerebral neuropils as well, forming the columnar neuropil (CN). In silver-impregnated cross-sections, nervous fibers can be traced those extend dorsally from the PB towards the MAN, form a chiasm anterior to the MAN, and bypass the OGT ventrally (Fig. 10A, B). These fibers connect the medial protocerebrum with the deutocerebrum and are here named the interconnecting tract (iT). The somata associated with these fibers are grouped in cell cluster (12) anterioventral to the MAN and in cell cluster (6) anterior to the PB (Fig. 10A, B, 13A). Further posteriorly, deutocerebral commissural Fibers (DCF) are visible in silver-stained cross-sections (Fig. (Fig.4D,4D, 13C), linking the cell cluster (16) across the MAN. The MAN is anteriorly penetrated by the dorsoventrally extending cerebral artery (CA; Fig. Fig.2,2, 3A, B, C, ,7,7, ,10,10, 13A, C). The cerebral artery bifurcates immediately ventral to the ON. Its branches are bent dorso-posteriorly towards the lateral antenna I neuropils, where the capillary ramification of the CA become untraceable (see Fig. 10A, B). It has been shown in different decapod species that the MAN receives multimodal inputs from the first antenna, namely descending interneurons related to the statocysts, branches of the antenna I motorneurons and mechanosensory afferents from sensilla of the antennal base as well [45,59]. Posterio-laterally to the MAN, the LAN displays SYNir, ASTir and SIFir. This neuropil is arranged in two more or less distinct elongated columns that fuse at the level of the OGT (Fig. 10A, D). The LAN extends dorsoventrally and fuses with the CN dorsally.
The tritocerebrum is represented by the barrel-shaped antenna II neuropil (AnN), lying posteriorly adjacent to the LAN and ON. It processes afferent input from the second ipsilateral antenna and provides neuromuscular efferent output via the antenna II nerve (AIINv). In cross-sections, labeled by immunohistochemistry, the AnN shows clear SYNir and ASTir. A stratified neuropil arrangement of the AnN like e.g. in Pagurus bernhardus (Krieger unpublished data) is indistinct in B. latro (Fig. 13B, C). Further dorsally, the AnN seems to be fused with the MAN and the mPC, forming the amorphous columnar neuropil (CN), which points posteriorly towards the oesophageal connective (OC). The tritocerebral tegumentary neuropil (TN) is not visible as a distinct structure in our data, but the tegumentary nerve (TNv) is present dorsally in several silver-impregnated cross-sections (Fig. (Fig.3B).3B). The TNv extends towards the columnar neuropil, where the location of the TN is assumed (see [45,47]).
The optic neuropils and visual abilities
In many respects the layout of the brain and general arrangement of neuropils in B. latro is quite similar to that in other decapods [43], specifically to that in another coenobitid, Coenobita clypeatus [40]. One major difference concerns the eyestalk neuropils, which in B. latro are shifted more proximally towards the brain so that the brain is longer than broad. This is also the case in a few other decapods species, e.g. Callianassa australiensis Dana, 1852 (Thallassinida) and Petrolisthes lamarckii Leach, 1820 (Anomura) [43,47]. The coconut crab features prominent eyestalks and fully developed compound eyes (Fig. (Fig.1)1) similar to other coenobitids. In fact, the retina is displaced many millimeters away from the brain. In other decapods, the strategy is to have the optic neuropils close to the eye so that retinula axons can be short but instead the protocerebral tract linking the optic neuropils and the lateral protocerebrum to the medial brain has to be long. On the contrary, B. latro has long retinula axons so that the protocerebral tract is very short. The functional role of this arrangement is still unresolved. Nevertheless, the neurochemistry and architecture of the three columnar optic neuropils in B. latro closely resemble that of other decapods [40,49,52,60] so that it is fair to assume that the visual analysis capacities of this creature matches those of other decapods. There is evidence that many terrestrial crustaceans, specifically members of the Brachyura have evolved good visual orientation abilities on land [5,61,62]. The visual system of fiddler crabs (Brachyura) is remarkable for its tuning to master the visual world of inter-tidal mud flats [62,63]. Their eyes are mounted on long vertical stalks and they have a panoramic visual field and a pronounced equatorial acute zone for vertical resolving power. Future anatomical studies on the ommatidia's optic apparatus will reveal which kind of adaptations have evolved in the B. latro eye to compensate for the different optic features of air versus water.
The central olfactory pathway and associated structures
As mentioned before, B. latro has established a sense of aerial olfaction and is therefore capable to detect food sources from long distances [37], as was also suggested for Coenobita clypeatus [40]. In Crustacea, the olfactory stimuli are detected by olfactory sensory neurons housed within the aesthetascs on the lateral flagellum of the bilaterally paired first antennae [41,42,64]. The aesthetascs of B. latro are short and blunt and arranged in ordered rows along the ventral side of the lateral flagella [37,65]. The behavioral findings on the sense of aerial olfaction in this animal are mirrored in the architecture of the central olfactory pathway as its central components, the olfactory neuropils and the hemiellipsoid neuropils, are greatly enlarged compared to other decapods. This feature has already been observed in a close relative of B. latro, the land hermit crab Coenobita clypeatus [40]. Together, these two neuropils of the central olfactory pathway account for about 40% of the total neuropil volume (Table. (Table.1).1). Olfaction can thus be suspected to be the major sensory modality that these brains process. The volume of the olfactory neuropils (AcN and ON) of freshwater crayfish (C. destructor and P. clarkii) and also the American lobster Homarus americanus represents 30-40% of the median brain volume [66,67]. Because these authors refer to the volume of the whole brain, not the neuropil volume, and because they do not include the volume of the optic ganglia into these calculations, it is difficult to compare these data with ours. Hanström [68] also conducted volumetric studies of several decapod crustaceans' brains and of other arthropods. His study is based on section series stained by hematoxylin and eosin. A comparison of absolute volumetric values with our data is difficult because Hanström [68] examined different species than we did and because he used a different set of histological and analytical methods which nevertheless was groundbreaking for that time. In the decapod species that he studied he reported the olfactory centers to take up between roughly 20% and 30% of the entire brain volume. For example, in the porcellanid crab Petrolisthes cinctipes Randall, 1840, the ("Riechzentren") olfactory centers amount to 23.9% of the whole brain volume, but the area of synaptic neuropil is presumably smaller and it is also unclear whether or not the author included the hemiellipsoid bodies as ("Riechzentrum") olfactory center.
The afferents from the first antennae enter the brain via the antenna I nerves from the ventral side and form a dense plexus that surrounds the entire ON. It is well known that in many decapods the primary afferents penetrate into and cross the entire olfactory glomeruli in a centripetal course from this plexus [69-71]. The olfactory glomeruli are arranged in a radial array around the periphery of the olfactory neuropil and are subdivided into a cap-, a base- and a subcap region [72,73], of which the latter shows strong ASTir in B. latro. From Cherax destructor Clark, 1936 is known that the subcap region of the olfactory glomeruli is interconnected with the ipsilateral accessory neuropil via neurites of olfactory interneurons that have their somata in cell cluster (9/11) [74]. We could not verify this connection with our methods, but in cluster (9/11) the somata of interneurons are present that show strong ASTir (Fig. 12A, B2), and the axons which project into the ON and most likely are the source of ASTir in the subcap of the glomeruli.
Another conspicuous feature of B. latro is the subdivision of its olfactory neuropil into three sublobes (Fig. (Fig.11;11; ONa, ONp and ONd), which seems to be unique among the anomuran decapods. In C. clypeatus, the olfactory neuropil is composed of two sublobes only, whereas most other decapods have only one lobe. This tripartition might be a primitive pre-stage of a cortical folding to increase the surface area, and thus offering a larger contact area between the enveloping plexus of the antennal nerves and the olfactory glomeruli. We estimate that this shape increases the surface area up to 30-40%, in comparison to a spherical body of the same volume. Furthermore, in combination with the elongate shape of the glomeruli, the subdivision into lobes may be another measure to economically increase the packing density of units in the system. Along these lines, the tendency to form sublobes observed in Coenobita clypeatus as well [40] may be an evolutionary precursor to the situation in B. latro.
In addition to the distinct olfactory glomeruli, the olfactory neuropil in Birgus contains six unstructured synaptic regions close to the posterior and medial foramina and at the transition from one sublobe to another. These unstructured neuropils, which interrupt the regular array of glomeruli and extend towards the center of the olfactory neuropil (Fig. (Fig.3A,3A, 4A, C, ,5C,5C, ,6A,6A, 11D), are labelled by roman numerals I-VI. The function of these neuropils remains unclear. One hypothesis is that these may be precursor structures of the glomeruli. Previous studies in the American lobster Homarus americanus Weber, 1795 have, however, shown that the number of olfactory glomeruli is almost stable in adult specimens [75]. From developmental studies in Cherax destructor is known that the number of glomeruli is set in early development and that the synaptic area increases with growth (Sandeman R. unpublished). The unstructured neuropils thus may provide additional synaptic target areas for increasing numbers of afferent inputs without having to add extra glomeruli with growth. Developmental studies will have to show if this is also the case in Coenobitidae.
Whereas the olfactory lobes are well elaborated, the AcN is comparatively small in size and shows only weak ASTir. The AcN is known to receive higher-order multimodal inputs but no primary afferents in other decapods [46]. The small AcN present in B. latro is typical for Brachyura and Anomura, whereas e.g. in crayfish and spiny lobster the size of this neuropil may equal or even exceed that of the olfactory neuropils [45]. According to Sandeman et al. [43] and Sandeman and Scholtz [47], small accessory neuropils are a synapomorphic feature for the Meiura (Anomura+Brachyura; [76]). In B. latro, the silver impregnated sections revealed a cluster housing extremely small cells adjacent to cluster (9/11) that send their axons into the AcN. An important input to the large AcNs in Cherax destructor enters along axons of interneurons that have their cell bodies dorsally in cluster (11). These interneurons have unilateral inputs from various areas of the brain but their axons decussate in the deutocerebral commissure and project bilaterally to the two AcNs [77]. The deutocerebral commissure is not identifiable in Birgus latro, implying that with the decrease in size and importance of the AcN, the need to bilateralize the inputs from the brain to these areas is no longer necessary as in the astacurans. In Cherax destructor both physiological and anatomical evidence indicate a connection between the axons of the projection neurons and large serotonergic neurons, the dorsal giant neurons (DGN), that project to all the glomeruli in both the AcN and ON in these animals [77,78]. A DGN homologue in Birgus latro has yet to be found.
The olfactory neuropil is connected with the hemiellipsoid neuropil and the terminal medulla of the ipsilateral as well as the contralateral protocerebrum [74,79]. Sullivan and Beltz [46] reported that in three species of the Astacidea Latreille, 1802, ascending projection neurons from the olfactory neuropil innervated primarily the terminal medulla, whereas the projection neurons of the accessory neuropil targeted exclusively the hemiellipsoid body. Although our methods did not allow us to analyze these connections in B. latro in such detail, it seems unlikely that the small accessory neuropil would provide the sole input to the giant hemiellipsoid neuropil, but that instead input from the olfactory neuropils must be dominant. The lateral protocerebrum also receives input from the lateral and median antenna I neuropils, which process mechanosensory, non-aesthetasc chemosensory and statocyst input [45,71]. Therefore, it has been suggested that the neuropils of the lateral protocerebrum have an integrating function for the multimodal mechanosensory, optic and olfactory inputs that they receive (reviews [42,80]).
Comparison to other crustaceans, functional implications and neuroethology
Among the marine and terrestrial Meiura (including anomuran and brachyuran crabs) studied so far (referring to [44]; Table. Table.2),2), Birgus latro, in absolute terms, has the largest olfactory neuropils, the largest olfactory glomeruli, and the highest number of olfactory glomeruli. Furthermore, the study by Harms 1932 [7] indicates that these animals also rank highly concerning the number of aesthetascs but it is difficult to extract which methods for counting this author used and what the size of the animals was that he examined. We estimate an aesthetasc number of 1,600 to 1,800 per lateral flagellum of an adult animal's first antenna, which is more than twice the number counted by Harms. Due to the fact that the aesthetasc number increases with growth in crayfish [44], we may assume that Harms examined a younger specimen than we did. Concerning absolute ON volume and glomerular numbers, the coconut crab together with other large crustaceans, spiny lobsters of the genera Jasus and Panulirus ranks among the top three of the decapods that have been described so far (Table. (Table.2).2). Together with the increase in size of the ON, the HN is also greatly enlarged, compared to other reptantian Decapoda such as Petrolisthes lamarckii (Anomura, Porcellanidae), Callianassa australiensis (Thallasinidea, Callianassidae), Carcinus maenas Linnaeus, 1758 (Brachyura, Portunidae), Gecarcoidea natalis (Brachyura, Gecarcinidae), Pagurus bernhardus Linnaeus, 1758 (Anomura, Paguridae) and Coenobita clypeatus (Anomura, Coenobitidae); [40,43,47] and Krieger (unpublished data). Although our cell counts have to be considered estimates, cell cluster (5) with 250,000 interneuronal somata and associated with the lateral protocerebrum, nevertheless must be considered the largest cell body cluster of the entire brain (Table. (Table.1;1; 160.000 projection neurons in cluster (10)). These numbers compare well with estimated cell counts in the spiny lobster Panulirus argus [69]. Our morphometric data of the neuropil volumes also are rough estimates, but the size relation between the neuropils is a close approximation to reality. For a better comparison with other taxa, we used the same calculation method as in the seminal study by Beltz et al. [44]. Compared to its close relative, the terrestrial hermit crab Coenobita clypeatus [44], the olfactory neuropils in B. latro (374,000,000 μm3) are three times larger and the olfactory glomeruli occupy twice the volume (Table. (Table.2).2). The olfactory glomeruli of B. latro are five to seven times longer than broad, and as noticed in C. clypeatus by Harzsch and Hansson [40], this elongation of glomeruli marks one extreme of glomerular architecture present in Decapoda, where glomeruli typically are not finger- but rather barrel-shaped (discussed in [40]). Such an elongated shape may be the best geometrical way to fit high numbers of glomeruli into the radial array typical of decapod olfactory neuropils.
Clearly, the olfactory neuropils and the gigantic hemiellipsoid neuropils are outstanding features of the B. latro brain. As mentioned above, the neuropils of the crustacean lateral protocerebrum have an integrating function for the multimodal mechanosensory, optic and olfactory inputs that they receive (reviews [42,80]). Along these lines, ablation experiments in the spiny lobster Panulirus argus suggest that the lateral protocerebrum is responsible for the discrimination between food sources and nonfood items as well as for the control of spatiotemporal aspects of feeding behavior [81-83]. What kind of olfactory input do these animals face in their natural environment and what do we know about their diet and feeding behavior? Adult B. latro are opportunistic omnivores who prefer the fruit and pith of fallen trees but who also will hunt for brachyuran land crabs which share their habitat [32]. There are many observations from a Christmas Island population (Indian Ocean) that the animals favor fruit and pith of the Lister's Palm Arenga listeri and that they form large feeding congregations around Lister's Palms when their fruits are ripe [37]. There has been much debate if the animals can in fact open undamaged coconuts but now there are several reports that B. latro does in fact make use of this attractive food item [37]. As mentioned above, electro-antennographic studies with the well developed first antennae demonstrated the capacity of this organ to detect volatile chemical information (review Hansson et al. [36]). Stensmyr et al. [37] concluded that their physiological experiments on B. latro point to a peripheral olfactory system as sensitive as the most sensitive general odor-detecting olfactory sensory neurons found in insects, and that therefore is well suited to explore the terrestrial olfactory landscape. In a set of behavioural experiments, these authors [37] have also analyzed the behaviour of a population of B. latro on Christmas Island toward baits with favoured food resources such as dead red crabs, coconut and pith of Lister's Palm but also with single odor compounds. The animals strongly reacted toward baits of the carcass odor dimethyl trisulfide and could detect the odor source from a distance of more than 50 m. Detection typically triggered an upwind search for the source, with the crabs constantly sampling the air by flicking their antennules. Furthermore, the animals effectively located the baits with food items whereas they ignored control baits [37]. Taken together, there is ample evidence that locating food items by odor is an important facet in the behavioural repertoire of these animals (review in [36]).
On Christmas Island B. latro undertake rhythmic reproductive migrations in that the females visit the coast to spawn (review [37]) similar to the endemic Christmas Island red crabs Gecarcoidea natalis (Brachyura; [84]). This means that females living on the central plateau of the island must travel up to 5 km to reach the coast. Recent observations (Hansson and Drew, unpublished observations) suggest that females undertake targeted migrations to coastal caves to copulate and that they remain in the caves while their extruded eggs mature before visiting the ocean to spawn (review [37]). Non- migratory movements are less well known. Recent studies using GPS loggers showed that during the study period (December 2008) ten out of the 12 animals tracked for more than five days ranged in an area less than 260 m2. Nevertheless, one male individual which was monitored over 32 days migrated from its home range to the coast (almost 2 km distance) and then used an almost identical trajectory back to its home range (Harzsch, Stensmyr, Erland, Hansson; unpublished data). Taken together these initial observations foster the realisation that the animals can orient very well on the island and somehow are able to remember the topography or certain landmarks to guide their migrations to the coast and back to their home range. The well documented ability of B. latro to frequently climb trees adds the third dimension to their locomotive repertoire. Terrestrial hermit crabs of the closely related genus Coenobita have a remarkable set of orientation mechanisms, including a celestial compass, visual landmarks, and wind direction to orient towards the coastline and to optimize their fleeing direction (e.g. [38,85]). Because B. latro has a comparably long life-span that is estimated to more than 40 years [86], the lateral protocerebrum with the gigantic hemiellipsoid bodies might not only be a multimodal integration centre but also a region of cognitive mapping as was suggested for other reptantian decapods [87]. Given the massive inputs from the olfactory lobes and from the visual neuropils to the hemiellipsoid bodies we may speculate about some link between odor source, visual landmarks and spatial cues that form a kind of integrative memory.
Any discussion about multimodal integration centers in the brains of arthropods would of course bring to mind the insect mushroom bodies as an obvious analogy to the robber crab hemiellipsoid bodies. It appears that the mushroom body lobes of the earliest insects mainly served mechano- and optosensory integration rather than olfaction [88,89]. The mushroom body calyx seems to have evolved later only after the ability to detect distant airborne odors was established, so that today the mushroom bodies of pterygote insects are thought to play an essential role not only in odor discrimination and formation of an olfactory memory [90] but also in the integration of visual, tactile and acoustic stimuli and coordinating behavioral repertoires [88,91]. Insect mushroom bodies are characterized by a massive input from projection neuron axons which have their dendrites in the glomeruli of the antennal lobes, a type of cell that, considering its connections, closely resembles the projection neurons of malacostracan crustaceans [71]. In insect mushroom bodies, the projection neuron axons contact the neurites of local interneurons, the Kenyon cells, in a rectilinear pattern. The functional equivalent to the Kenyon cells in the B. latro brain would be the 250,000 interneurons in cell cluster (5) of the lateral protocerebrum. Unfortunately, the cellular architecture of the hemiellipsoid bodies in Coenobitidae is not yet known in detail. Nevertheless, unpublished work in progress using a silver impregnation technique suggests a rectilinear arrangement of alternating neurite bundles in the terrestrial hermit Coenobita clypeatus (Strausfeld, Harzsch, Hansson; unpublished data) as is also apparent in our Bodian stained preparations. The hemiellipsoid bodies of Coenobitidae may therefore represent functional analogs to insect mushroom bodies.
Similar to B. latro, endemic Christmas Island red crabs Gecarcoidea natalis (Brachyura) do undertake pronounced reproductive migrations, and visual cues, polarized light and magneto-reception have been suggested as navigational mechanisms [84]. Radio tracking experiments revealed that some specimens traveled more than 4 km within 6 days to reach the shoreline and to spawn. The crabs seem to have specific shore destinations to which they return each year. Interestingly, when returning from the shore to the central plateau of the island, some red crabs appear to follow a route similar to the one they took during their downward migration [84], an observation that matches our initial GPS tracking data for B. latro. One major difference between these two species which share the same habitat is that the red crab olfactory system is poorly developed, both in terms of minute antennae and minute olfactory lobes when compared to similarly sized marine brachyuran crab species (Krieger, Hansson, Harzsch; unpublished data). Despite their impressive navigational skills, olfactory cues seem to play a minor role in the sensory world of red crabs. Our initial neuroanatomical data suggest that concurrent with their olfactory lobes their hemiellipsoid bodies are also comparatively small.
In a previous study on the terrestrial hermit crab Coenobita clypeatus we have shown that the central olfactory pathway in these animals is well developed compared to other brain areas and matching behavioral observations suggest that these animals have evolved aerial olfaction [40]. The present study shows that B. latro has even more inflated the amount of neuronal substrate in the central olfactory pathway, and these morphological characteristics correlate well with the proven ability to detect volatile substances in these terrestrial anomurans (see [37-39]). The primary olfactory centers are the dominating neuropils of the medial brain in B. latro. The secondary olfactory centers (hemiellipsoid neuropils) are also large and organized into parallel neuropil lamellae. Thus, we suggest that the expansion of the HN may compensate for the reduction of the AcN as integrating neuropil which is obvious in both Anomura and Brachyura. The paired olfactory neuropils of B. latro are composed of more than 1,000 glomeruli, ca. 90,000 local interneurons and ca. 160,000 projection neurons per side. The secondary olfactory centers, the paired hemiellipsoid neuropils, are targeted by the axons of these olfactory projection neurons which make contact to ca. 250,000 interneurons associated with the hemiellipsoid neuropils with the result that the olfactory input could be analyzed by ca. 500,000 olfactory interneurons per side. For insects with well developed olfactory systems [71] the numbers of local interneurons amounts to between ca. 400 (Manduca sexta) and 4,000 (Apis mellifera) and that of projection neurons to ca. 800 - 900 (M. sexta and A. mellifera). Thus, the numbers of interneurons in the central olfactory pathway of B. latro surpasses that of insects by two orders of magnitude. In accordance with these interneuron numbers, the total neuropil volume of the honeybee brain (A. mellifera) with ca. 4.48 × 108 μm3 is more than six times smaller than in B. latro [92]. However, it is difficult to discuss such absolute volumes as long as a reference to absolute body size is not possible. In terms of percentage of total neuropil volume, the primary olfactory processing areas (antennal lobes, 2.17 × 107 μm3) in A. mellifera amount to ca. 4.84%. This is a comparatively low value in relation to the 40% of neuropil volume occupied by the central olfactory pathway in B. latro. Hanström [68] already noted that decapod crustaceans dedicate relatively more neuronal tissue in their brains to the analysis of chemical stimuli than is the case in insects when writing: ("Einige der erzielten neuen Resultate der vorliegenden Arbeit können auch als festgestellte Tatsachen gelten. Solche sind: ... 2. der Nachweis der im Verhältnis zu den Crustaceen ungeheuer großen Entfaltung der Sehzentren der Insekten und der überraschend unbedeutenden Entwicklung der Riechzentren derselben" Some of the new results presented here can be considered established facts. These are: ... 2. evidence for the in relation to crustaceans enormous enlargement of the visual centers of insects and their surprisingly unimportant development of the olfactory centers).
Such comparison has to consider that the entire life span of the giant robber crab is much longer (40 years and more) than that of bees and that their olfactory pathway may not only serve the purpose of sensory analysis but also the formation of olfactory memory. Furthermore, it recently has been suggested that brain size may be less related to a complex behavioral repertoire and cognitive capacity than has been generally assumed [93]. These authors propose that "While some increases in brain size will affect cognitive capacity, many increases in certain brain areas - especially those involved in sensory and motor processing - produce only quantitative improvements: more detail, finer resolution, higher sensitivity, greater precision - in other words, more of the same." Miniaturization as seen in many insects may evoke the adaptive strategy to tune a brain to operate more economically and efficiently and to perform its task with less redundancy of neuronal circuits [93,94]. The brain of B. latro may suffer far less from limited energy resources than insect brains do. Therefore it may be less economical in performing the same olfactory tasks and need more neuronal hardware to do so. However, let us consider the numbers of olfactory glomeruli in the primary olfactory centers which in insects are considered a good estimate of the number of olfactory receptor proteins (ORs) expressed in antennal olfactory sensory neurons and therefore provides insights into the odor space that certain species can analyze. For example, Drosophila melanogaster expresses 62 functional olfactory receptor proteins [95] and Apis mellifera 170 [96]. Although in crustaceans it is unknown if a similar correlation exists - i.e. more olfactory glomeruli means a greater diversity of olfactory receptor proteins (if crustaceans have any of these proteins at all) - we would like to remind that with approximately 1,340, B. latro, together with members of the genus Panulirus, has the highest number of olfactory glomeruli among all malacostracan crustaceans studied so far. Does this suggest a high level of odor discrimination, a high level of sensitivity, or does it mirror an uneconomical olfactory system? Chittka and Niven [93] suggest that "Increases in the volume of central brain regions can occur through the replication of nearly identical circuits - most likely engaged in more parallel processing ..." and "Within large brains, additional parallel processing pathways and stages of serial processing allowing the computation of novel receptive fields may be added more easily that in insect brains where space may impose more severe constraints." So, in B. latro, do we face an example where a multiplication of parallel processing pathways in the olfactory lobe - hemiellipsoid body system may in fact serve "quantitative improvements: more detail, finer resolution, higher sensitivity, greater precision" [93]?
Whatever the answer to this question may be, we can conclude that aerial olfaction plays a major role in the behavioral repertoire of all members of the Coenobitidae. Future studies using backfill methods should reveal more details of the olfactory pathway in these animals. The organization of the optic neuropils and those neuropils associated with antenna 2 suggest that both C. clypeatus and B. latro have visual and mechanosensory skills that are comparable to those of other Decapoda. However, it would appear that contrary to many terrestrial members of the Brachyura [62] the Coenobitidae have not fine-tuned their visual senses, but instead sharpened their olfactory senses for orientation in their terrestrial habitat. This aspect makes this species an extremely attractive model to analyze the sense of smell in arthropods.
The neuroanatomical nomenclature, used in this manuscript is based on Sandeman et al. [45] with some modifications adopted from Harzsch and Hansson [40]. We consistently use the terms hemiellipsoid-, olfactory- and accessory neuropil according to Sandeman et al. (45) but have to note that other publications since use the terms hemiellipsoid body, olfactory lobe and accessory lobe in a synonymous way. The traditional nomenclature of the optic neuropils lamina ganglionaris, medulla interna, medulla externa has been modified here as suggested by Harzsch [50] to lamina, medulla, and lobula.
Silver impregnations
Specimens of Birgus latro used for silver impregnation staining were obtained from Christmas Island. The anterior of the cepaholothorax was removed from the animals and the exposed brains and fixed in cold, aged alcoholic Bouin's fixative for 2 to 3 days after which they were washed and dissected free from the surrounding tissues. They were dehydrated in an ethanol series, cleared in xylene and embedded in paraffin wax. 10 micron serial sections were mounted on glass slides and stained using a modification of the Holmes-Blest silver impregnation method [97] in which impregnation times were increased up to 24 hours and toned with a 2% gold solution.
Brains of four adult Birgus latro were obtained from specimens that were freshly killed in the heavy road train traffic associated with phosphate mining on, Christmas Island, Indian Ocean in December 2008 with permission of the Australian wildlife protection authorities. The brains were dissected in phosphate buffered saline (0.1 M PBS, pH 7.4) then fixed in 4% PFA in 0.1 PBS, pH 7.4 at 4°C, stored in Eppendorf tubes and then transported to the Zoological Institute, University of Greifswald. For the immunohistochemical experiments, the brains were washed for 4 hours in several changes of PBS and then sectioned (100 μm) with a Carl Zeiss vibratome (Hyrax) at room temperature. The sections were then preincubated for 90 minutes in PBS-TX (1% Bovine-Serum-Albumine, 0.3% TritonX-100, 0.05% Na-acide, pH 7.4) followed by the overnight incubation of the primary antibodies at room temperature diluted in PBS-TX. We used the following antisera for the triple labeling experiment (three section series): polyclonal rabbit anti-allatostatin (in PBS-TX; final dilution 1:1000; Abcam; Cat. No. AB53956), and monoclonal mouse anti-synapsin "SYNORF1"antibody (in PBS-TX; final dilution 1:2000; DSHB). For labeling against SIFamide related peptides, the primary rabbit anti-SIFamide antibody (final dilution 1:12.000; [98]) was used on the fourth section series. Subsequently, all tissues were washed in several changes of PBS for 2 hours at room temperature and incubated in a mix of the secondary anti-rabbit Alexa Fluor 488 antibodies, secondary anti-mouse Cy3 antibodies and the nuclear dye bisbenzimide as a histochemical counterstain (0.05%, Hoechst H 33258) for another 4 hours. For SIFamide labelling, specimens were incubated in a secondary Alexa Fluor 488 goat anti-rabbit immunoglobulin (1:50, Invitrogen, Eugene, or, USA) overnight at 4°C. Finally, the tissues were washed for at least 2 hours in several changes of PBS at room temperature and mounted in Mowiol. The labelled tissues were viewed with a Nikon eclipse 90i microscope connected to a Nikon camera DS2-MBWc and analyzed with the computer system using NIS-Elements AR softwareDigital images were processed with the Lucia 4.82 software package (Laboratory Imaging Ltd.) and Photoshop Elements (Adobe). Pictures were optimized with the global picture enhancement features of Photoshop elements (brightness/contrast). The pictures, obtained from the SIFamide labeling were black-white inverted.
Antibody specifity
The monoclonal mouse anti-Drosophila synapsin "SYNORF1" antibody (provided by E. Buchner, Universität Würzburg, Germany) was raised against a Drosophila GST-synapsin fusion protein and recognizes at least four synapsin isoforms (ca. 70, 74, 80, and 143 kDa) in western blots of Drosophila head homogenates [99]. In western blot analysis of crayfish homogenates, this antibody stains a single band at ca. 75 kDa (see [55]). Harzsch and Hansson, [40] conducted western blot analysis comparing brain tissue of Drosophila and Coenobita. The antibody provided identical results for both species staining one strong band around 80-90 kDa and a second weaker band slightly above 148 kDa (see [40]). Their analysis strongly suggests that the epitope which SYNORF 1 recognizes is strongly conserved between the fruit fly and the hermit crab. Similar to Drosophila, the antibody consistently labels brain structures in representatives of all major subgroups of the malacostracan crustaceans (see [40,44,100-103]) in a pattern that is consistent with the assumption that this antibody does in fact label synaptic neuropil in Crustacea. In the crustacean first optic neuropil (the lamina), synapsin labeling is weak compared to the other brain neuropils [40,103]. Similarly, in Drosophila labeling of the lamina is weak because photoreceptors R1-R6 which have their synapses in the lamina contain very little of the presently known synapsin homolog isoforms [99]. The antibody also labels neuromuscular synapses both in Drosophila and in Crustacea [103]. These close parallels in the labeling pattern of SYNORF1 between Drosophila and various Crustacea strengthen the claim that it also recognizes crustacean synapsin homologs. Beyond the arthropods, this antibody even labels synaptic neuropil in ancestral taxa of protostomes such as the Chaetognatha [104,105] and Plathelminthes [106] suggesting that the epitope that this antiserum recognizes is highly conserved over wide evolutionary distances.
Crustacean-SIFamide is a 1,381-Da peptide that has been identified in the crayfish P. clarkii by topological mass spectrometry analysis in combination with MALDI-TOF MS using slices of tissues, chromatographic purification from the extract of tissues, molecular cloning for the determination of the precursor structure, and capillary liquid chromatography tandem mass spectrometry (LC-MS/MS) analysis for elucidation of its posttranslational modifications ([98,107]. The cDNA of this peptide has been characterized to encode a 76 amino acid precursor protein that contains a signal sequence, one copy of GYRKPP FNGSIFG and one additional peptide. Initial reverse transcriptase polymerase chain reaction (RT-PCR) analysis had demonstrated the presence of mRNA of this neuropeptide throughout the crayfish brain. Furthermore, direct MALDI-TOF MS analysis with microdissectates showed crustacean-SIFamide to be present in the olfactory neuropils, accessory neuropils, olfactory neuropil cells, anterior medial cells and posterior medial cells. The antigen used for generation of the antiserum (injection into rabbit) was (Cys)GYRKPPFNGSIF-CONH2 conjugated to bovine serum albumin (BSA) by the material basis set (MBS) method with NH2 [98]. Initial immunolocalization experiments with this antiserum in the crayfish [52] revealed a labeling pattern that closely corresponded to the experimental results of the aforementioned mass spectrometric morphology for crustacean-SIFamide [98]. More specifically, mass spectrometry analysis demonstrated that positively immunostained structures such as the lateral cell cluster 10, which houses olfactory projection neurons [43,47], in fact included the crustacean-SIFamide molecule. In subsequent experiments, the specificity of the antiserum was further substantiated. A digoxigenin-labeled antisense RNA probe prepared by in vitro transcription with partial preprotein cDNA as a template (1-313 in AB036713) was used for an in situ hybridization analysis of the crayfish brain [108]. The crustacean-SIFamide mRNA expression pattern was identical with the data obtained by the previous immunohistochemical analysis [98]. The antiserum also labels the projection neurons in another crayfish species [52] and the brachyuran crab Libinia emarginata [109]. Therefore, we expect that in B. latro the antiserum also recognizes crustacean-SIFamide. However, because but we cannot exclude the possibility that the antibody also binds to related peptides we will refer to "SIFamide-like immunoreactivity" throughout the paper.
Allatostatin peptides share the conserved C-terminal sequence -YXFGL-NH2 [110] and are present in the nervous system of all insects analyzed so far (reviewed in [111]). Allatostatins are often colocalized with other transmitters, for example with GABA and other peptides in antennal lobes of moths [112,113]. Co-release with GABA is likely related to the inhibitory function of AST. The antiserum against Diploptera punctata (Pacific beetle cockroach) allatostatin I (Dip-allatostatin I, APSGAQRLYGFGL-amide) was provided by H. Agricola (Friedrich-Schiller Universität Jena, Germany). Vitzthum et al. [114] have characterized the Dip-allatostatin I antibody. It recognizes all Dip-allatostatins. No cross-reactivity was found with corazonin, CCAP, FMRFamide, leucomyosuppression, locustatachykinin 11, perisulfakinin, and proctolin as tested by non-competitive ELISA. Vitzthum et al. [114] showed that preadsorption of the diluted antisera against Dip-allatostatin I, GMAP and Manduca sexta allatotropin with 10 μM of their respective antigens abolished all immunostaining in brain sections of Schistocerca gregaria. For Crustacea, the antiserum was shown to label neurons in the central complex of the crayfish Cherax destructor [53]. However, because but we cannot exclude the possibility that the antibody also binds to related peptides in B. latro, we will refer to "allatostatin-like immunoreactivity" throughout the paper.
Morphometric Analysis
For morphometry, aesthetasc numbers, cell numbers of the cell clusters (9), (10) and (11) were determined and the volumes of these cell clusters, the olfactory neuropils, the accessory neuropils, the hemiellipsoid neuropils and the neuropil volume of the entire brain were calculated.
To determine the neuropil volumes from the immunostained section of one animal, each section was viewed with a Nikon eclipse 90i microscope connected to a Nikon camera DS2-MBWc and analyzed with the computer system using NIS-Elements AR software. All synapsin labeled areas were selected and measured for each neuropil, except the AcN, and transferred into a Microsoft Excel table. Finally, the sum of all areas for each neuropil was multiplied by the section thickness of 100 μm to provide a total volume of the neuropils. Assuming that the accessory neuropil has an idealized spherical shape, the volume of the AcN was calculated via its diameter.
To obtain a mean value of a single olfactory glomerulus, the lengths and the cross sectional areas of ten randomly selected glomeruli of each olfactory neuropil were recorded. Next, the average of the cylindrical and the conical volume was calculated, because the olfactory glomeruli of B. latro have a conical as well as cylindrical shape. Finally, by dividing the total glomerular volume obtained before by the mean volume of a single glomerulus, the total glomerular number for each olfactory neuropil could be estimated.
For the cell counts of the cell cluster (10), (9/11) and the deutocerebral organ of another specimen, the series of silver-stained cross sections with a thickness of 10 μm per slice was examined. In different slices and in randomly selected subareas within the specific clusters, the average diameters of at least 30 cells per cluster were calculated. Based on an idealized spherical shape of the cells, the mean cell volume of each cluster was computed. Mean values for the packing densities were calculated for the ratio of the area filled by somata to a randomly pre-set area, at least five times per cluster. The maximum cell count for each slice was calculated by the quotient of the previously calculated cell cluster volume and the obtained mean cell volume. But due to the fact that the cells are not homogeneously distributed and only the cores are visible, the packing density was implicated into the calculation to obtain finally the estimated cell count for each cluster.
The silver-stained cross sections of 89 sections (10 μm) were viewed under a Nikon eclipse 90i microscope with a digital camera Nikon DS2-MBWc camera by using a 4× dry objective with a numeric aperture of 0.13. Each section was photographed as a mosaic of 2 × 3 single pictures, composed with Nikon's Imaging Software NIS-Elements AR. The three dimensional brain reconstruction of B. latro is based on this series and was prepared by using Bitplane's AutoAligner and Imaris 3 D reconstruction software. An exchange ratio of 1.587 was calculated from the proportion of 1.587 μm: 1 pixel. Therefore, the voxel z-dimension was set to 1.587 × 10 μm. The x y resolution of each stack was 2251 × 2990 pixels over a total scan area of 3.77 mm × 4.74 mm.
List of Abbreviations
I-VI: noncolumnar olfactory neuropils; AINv: antenna I nerve; AIINv: nerve of Antenna II; AcN: accessory lobe/neuropil; AMPN: anterior medial protocerebral neuropil; AnN: antenna II neuropil; CA: cerebral artery; Cap: cap neuropil of the hemiellipsoid neuropil; CB: central body neuropil; CN: columnar neuropil; CO1, CO2: core neuropils 1 and 2 of the hemiellipsoid neuropil; DCF: deutocerebral commissural fibers; DGN: serotonergic dorsal giant neuron; DO: deutocerebral organ; HN: hemiellipsoid neuropil; ICh: inner optic chiasm; IL1, IL2: intermediate layers 1 and 2 of the hemiellipsoid neuropil; iT: interconnecting tract; La: Lamina (lamina ganglionaris); LAN: lateral antenna 1 neuropil; Lo: lobula (medulla interna); LoP: lobula plate; lPC: lateral protocerebrum; MAN: median antenna I neuropil; Me: Medulla (medulla externa); mF: median foramen; mPC: Medial protocerebrum; OC: oesophageal connectives; OCh: outer optic chiasm; OGT: olfactory globular tract; OGTN: olfactory globular tract neuropil; OGTNa: accessory olfactory globular tract neuropil; ON: olfactory lobe/neuropil; ONv: optic nerve; OT: optic tract; PB: protocerebral bridge; pF: posterior foramen; PMPN: posterior medial protocerebral neuropil; PT: protocerebral tract; TM: terminal medulla; TN: tegumentary neuropil; TNv: tegumentary nerve; X: chiasm of the olfactory globular tract.
Competing interests
The authors declare that they have no competing interests.
Authors' contributions
SH and BSH conducted the sampling, preparation and fixation of brains on Christmas Island for the immunohistochemical experiments. JK carried out most of the immunohistochemical experiments, performed the 3 D reconstruction, and the microscopic and morphometric analysis. SH carried out the SIFamide immunolocalization experiment including microscopic analysis. RES and DCS obtained, sectioned, and stained the brain for the Bodian series. JK drafted the main part of the manuscript and all other authors assisted in drafting the manuscript. All authors read and approved the final manuscript.
The monoclonal antibody Synorf1 developed by E. Buchner was obtained from the Developmental Studies Hybridoma Bank developed under the auspices of the NICHD and maintained by The University of Iowa, Department of Biology, Iowa City, IA 52242. We wish to thank Hans Agricola (Friedrich Schiller University Jena) for allatostatin antiserum. We like also to express our thanks to A. Yasuda (Suntory Institute for Bioorganic Research, Osaka, Japan) for providing us the GYRKPPFNGSIFamide-antibody.
The authors are grateful for the assistance of personnel at National Parks Australia, Christmas Island office in locating road-killed crabs, and for their general support.
This study was supported by the Max Planck Society.
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Josiah W. Gibbs, a professor of linguistics at Yale, was the man most responsible for bringing the African's own story of the Amistad incident to the American people. It was through the determined efforts of Gibbs that a Mendi translator was located.
Josiah Gibbs began his work by visiting the Africans in their New Haven cell. He held up a finger and said "one." He held up a single coin and said "one." Finally, Grabeau sensed what Gibbs was trying to do and shouted "eta," the Mendi word for one. Eventually, Gibbs began to build up a limited Mendi vocabulary, including words for the numbers one through ten. In the course of these efforts, Gibbs was also able to determine that at least three different African languages were represented in the group, although most were Mendi speakers.
Gibbs began a search for an English-speaking Mendi on the waterfronts of New Haven and New York. He would go up to blacks and begin counting from one to ten in Mendi, looking for signs of recognition. In New Haven, he found a sailor named John Ferry who knew some Mendi, but his vocabulary proved too limited to be of much use and Gibbs continued his search along the New York waterfront. James Covey, rescued from a slave boat by the British and trained by British missionaries in Sierra Leone, turned out to be the key to unlocking the Amistad Africans' story. Gibbs received permission from the captain of the H.M..S. Buzzard, the British warship which employed Covey, to take him to meet the Africans. Soon the captives began to spill out heir stories of their lives in Sierra Leone, their capture, their voyages, and their mutiny. Gibbs undertook an extensive interrogation of Cinque, who then asked Gibbs if he could arrange for them instruction in the English language. Gibbs replied that he would gladly do so.
In January of 1840, Gibbs testified at the district court trial in Hartford. He began with a detailed explanation of the importance of language to a determination of whether the Amistads were recently arrived from Africa, or had resided for years in Cuba, as their documents indicated. He pointed out how the name of each corresponded to a place, object, or thing in Mendi, and how if they had been in Cuba for years their names would have been "corrupted in form and sound." Gibbs testimony was finally cut off by Judge Judson who announced that he was "fully convinced that the men were from Africa, and it is idle to deny it."
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inselberg, ( from German: Insel, “island,” and Berg, “mountain”) Pilot Mountain, North Carolina.Ollie Keyworthisolated hill that stands above well-developed plains and appears not unlike an island rising from the sea. The early German explorers of southern Africa were impressed by such features, and they dubbed the domed or castlelike highlands inselbergs. Spectacular examples include Uluru/Ayers Rock and the Olga Rocks (Kata Tjuta) in central Australia.
Inselbergs are relict features. They have maintained their relief as the adjacent surrounding landscape was lowered. C.R. Twidale of Australia demonstrated the role of subsurface weathering in shaping the flanking hillslopes and pediments of granitic inselbergs.
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1911 Encyclopædia Britannica/Ballot
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For works with similar titles, see Ballot.
BALLOT (from Ital. ballotta, dim. of balla, a ball), the modern method of secret-voting employed in political, legislative and judicial assemblies, and also in the proceedings of private clubs and corporations. The name comes from the use of a little ball dropped according to choice into the right receptacle; but nowadays it is used for any system of secret-voting, even though no such ball is employed. In ancient Athens, the dicasts, in giving their verdict, generally used balls of stone (psephi) or of metal (sponduli). Those pierced in the centre, or black in colour, signified condemnation; those unpierced, or white, signified acquittal. The boxes were variously arranged; but generally a brass box received both classes of votes, and a wooden box received the unused balls. In the assembly, cases of privilegia, such as ostracism, the naturalization of foreigners or the release of state-debtors, were decided by secret-voting. The petalism, or voting by words on olive-leaves, practised at Syracuse, may also be mentioned. At Rome the ballot was introduced to the comitia by the Leges Tabellariae, of which the Lex Gabiana (139 B.C.) relates to the election of magistrates, the Lex Cassia (137 B.C.) to judicia populi, and the Lex Papiria (131 B.C.) to the enactment and repeal of laws. The wooden tabellae, placed in the cista or wicker box, were marked U. R. (uti rogas) and A. (antiquo) in the case of a proposed law; L. (libero) and D. (damno) in the case of a public trial; in the case of an election, puncta were made opposite the names or initials of the candidates. Tabellae were also used by the Roman judices, who expressed their verdict or judgment by the letters A. (absolvo), C. (condemno), and N. L. (non liquet). In modern times voting by ballot is usually by some form of writing, but the use of the ball still persists (especially in clubs), and a "black ball" is the regular term for a hostile vote.
Great Britain.—In Great Britain the ballot was suggested for use in parliament by a political tract of the time of Charles II. It was actually used by the Scots parliament of 1662 in proceeding on the Billeting Act, a measure proposed by Middleton to secure the ostracism of Lauderdale and other political opponents who were by secret-vote declared incapable of public office. The plan followed was this: each member of parliament wrote, in a disguised hand, on a piece of paper, the names of twelve suspected persons; the billets were put in a bag held by the registrar; the bag was then sealed, and was afterwards opened and its contents ascertained in the exchequer chamber, where the billets were immediately burned and the names of the ostracised concealed on oath. The Billeting Act was repudiated by the king, and the ballot was not again heard of till 1705, when Fletcher of Saltoun, in his measure for a provisional government of Scotland by annual parliaments in the event of Queen Anne's death, proposed secret-voting to protect members from court influence. The gradual emancipation of the British parliament from the power of the crown, and the adoption of a strictly representative system of election, not only destroyed whatever reason may once have existed for the ballot in deliberative voting, but rendered it essential that such voting should be open. It was in the agitations for parliamentary reform at the beginning of the 19th century that the demand for the ballot in parliamentary elections was first seriously made. The Benthamites advocated the system in 1817. At the so-called Peterloo Massacre (1819) several banners were inscribed with the ballot. O'Connell introduced a bill on the subject in 1830; and the original draft of Lord John Russell's Reform Bill, probably on the suggestion of Lords Durham and Duncannon, provided for its introduction. Later on the historian Grote became its chief supporter in the House of Commons; and from 1833 to 1839, in spite of the ridicule cast by Sydney Smith on the "mouse-trap," and on Grote's "dagger-box, in which you stab the card of your favourite candidate with a dagger,"[1] the minority for the ballot increased from 106 to 217. In 1838 the ballot was the fourth point of the People's Charter. In the same year the abolition of the land qualification introduced rich commercial candidates to the constituencies. Lord Melbourne's cabinet declared the question open. The cause, upheld by Macaulay, Ward, Hume (in his resolutions, 1848) and Berkeley, was strengthened by the report of Lord Hartington's Select Committee (15th March 1870), to the effect that corruption, treating and intimidation by priests and landlords took place to a large extent at both parliamentary and municipal elections in England and Ireland; and that the ballot, if adopted, would probably not only promote tranquillity at elections, but protect voters from undue influence, and introduce greater freedom and purity in voting, provided secrecy was made inviolable except in cases where a voter was found guilty of bribery, or where an invalid vote had been given.
Meanwhile in Australia the ballot had been introduced by the Constitution Act of South Australia (1856), and in other colonies at the same date. In South Australia (Electoral Act of 1858) the returning-officer put his initials on the voting-card, which the voter was directed, under pain of nullity, to fold so that the officer might not see the vote which was indicated by a cross. In Victoria, under the Electoral Act of 1865, the officer added to his initials a number corresponding to the voter's number on the register. In Tasmania the chief peculiarity was that (as in South Australia) the card was not put directly by the voter into the box, but handed to the officer, who put it there (this being thought a security against double-voting or voting with a non-official card, and also against the voter carrying away his card). In 1869, at Manchester and Stafford in England, test-ballots were taken on the Australian system as practised in Victoria—the voting-card containing the names of all the candidates, printed in different colours (for the benefit of illiterate voters), and the voter being directed to score out the names of those he did not support, and then to place the card (covered by an official envelope) in the box. It was found at Manchester that the voting was considerably more rapid, and therefore less expensive, than under the old system; that only 80 cards out of 11,475 were rejected as informal; and that, the representatives of candidates being present to check false statements of identity, and the public outside being debarred from receiving information what voters had voted, the ballot rather decreased the risk of personation. At Manchester the cards were not numbered consecutively, as in Victoria, so that (assuming the officials to be free from corruption) no scrutiny could have detected by whom particular votes were given. At Stafford the returning-officer stamped each card before giving it to the voter, the die of the stamp having been finished only on the morning of the election. By this means the possibility was excluded of what was known as "the Tasmanian Dodge," by which a corrupt voter gave to the returning-officer, or placed in the box, a blank non-official ticket, and carried out from the booth his official card, which a corrupt agent then marked for his candidate, and gave so marked to corrupt voter No. 2 (before he entered the booth) on condition that he also would bring out his official card, and so on ad libitum; the agent thus obtaining a security for his bribe, unless the corrupt voter chose to disfranchise himself by making further marks on the card. At the close of 1870 the ballot was employed in the election of members for the London School Board under the Education Act of that year.
In 1872 W. E. Forster's Ballot Act introduced the ballot in all parliamentary and municipal elections, except parliamentary elections for universities; and the code of procedure prescribed by the act was adopted by the Scottish Education Board in the first School Board election (1873) under the Education (Scotland) Act 1872. The Ballot Act not only abolished public nominations of candidates, but dealt with the offence of personation and the expenses of elections.
As practised in the United Kingdom, a white paper is used on which the names of the candidates are printed in alphabetical order, the voter filling up with a X the blank on the right-hand opposite the name he votes for. The paper, before being given out, is marked by the presiding-officer on both sides with an official stamp, which is kept secret, and cannot be used for a second election within seven years. The paper is marked on the back with the same number as the counterfoil of the paper which remains with the officer. This counterfoil is also marked with the voter's number on the register, so that the vote may be identified on a scrutiny; and a mark on the register shows that the voter has received a ballot-paper. The voter folds up the paper so as to conceal his mark, but to show the stamp to the officer, and deposits it in the box, which is locked and sealed, and so constructed that papers cannot be withdrawn without unlocking it. Papers inadvertently spoiled by the voters may be exchanged, the officer preserving separately the spoiled papers. If a voter is incapacitated from blindness, or other physical cause, or makes before the officer a declaration of inability to read, or when the poll is on a Saturday declares himself a Jew, the officer causes the paper to be marked as the voter directs, and keeps a record of the transaction. A voter who claims to vote after another has voted in respect of the same qualification, obtains a (green) paper which is not placed in the box, but preserved apart as a "tendered" paper. He must, however, declare his identity and that he has not already voted. The presiding-officer at the close of the poll has to account to the returning-officer for the papers entrusted to him, the number being made up by—(1) papers in the box, (2) spoiled papers, (3) unused papers and (4) tendered papers. During the voting (for which schoolrooms and other public rooms are available, and for which a separate compartment must be provided for every 150 electors entitled to vote at a station) agents of candidates are allowed to be present in the polling-station, but they, as well as the officials, are sworn to secrecy as regards who have voted, and for whom; and they are prohibited from interfering with the voter, inducing him to show his vote, or attempting to ascertain the number on the back of the paper. These agents are also present with the returning-officer when he counts the papers and the votes, rejecting those papers—(1) which want the official mark on the back; (2) on which votes are given for more candidates than the voter is entitled to vote for; (3) on which anything except the number on the back is marked or written by which the voter can be identified; (4) which are unmarked, or so marked that it is uncertain for whom the vote is given. The counted and rejected papers, and also the "tendered" papers, counterfoils and marked register (which have not been opened), are, in parliamentary elections, transmitted by the returning officer to the clerk of the crown in chancery in England, or the sheriff-clerk in Scotland, who destroys them at the end of one year, unless otherwise directed by an order of the House of Commons, or of some court having jurisdiction in election petitions. Such petitions either simply dispute the accuracy of the return on the ground of miscounting, or wrongous rejection or wrongous admission of papers, in which case the court examines the counted and rejected papers; or make allegations of corruption, &c. on which it may be necessary to refer to the marked counterfoils and ascertain how bribed voters have voted. Since the elections of 1874 much discontent has been expressed, because judges have rejected papers with trifling (perhaps accidental) marks other than the X upon them, and because elections have been lost through the failure of the officer to stamp the papers. For this purpose the use has been suggested of a perforating instead of an embossing stamp, while a dark-ground paper with white voting-spaces would make misplaced votes impossible.
The Ballot Act introduced several new offences, such as forging of papers or fraudulently defacing or destroying a paper or the official mark; supplying a paper without due authority; fraudulently putting into the box a non-official paper; fraudulently taking a paper out of the station without due authority; destroying, taking, opening or otherwise interfering with a box or packet of papers then in use for election purposes. These offences and attempts to commit them are punishable in the case of officers and clerks with imprisonment for two years, with or without hard labour. In other cases the term of imprisonment is six months.
The ballot was long criticized as leading to universal hypocrisy and deception; and Sydney Smith spoke of "voters, in dominos, going to the poll in sedan-chairs with closely-drawn curtains." The observed effect of a secret ballot has been, however, gradually to exterminate undue influence. The alarm of "the confessional" seems to be unfounded, as a Catholic penitent is not bound to confess his vote, and if he did so, it would be a crime in the confessor to divulge it.
Continental Europe.—The ballot is largely employed in European countries. In France, where from 1840 to 1845 the ballot, or scrutin, had been used for deliberative voting in the chamber of deputies, its use in elections to the Corps Législatif was carefully regulated at the beginning of the Second Empire by the Organic Decree of the 2nd of February 1852. Under this law the voting was superintended by a bureau consisting of the deputy returning-officer (called president of the section), four unpaid assessors selected from the constituency and a secretary. Each voter presents a polling-card, with his designation, date of birth and signature (to secure identity), which he had previously got at the Mairie. This the president mutilates, and the vote is then recorded by a "bulletin," which is not official, but is generally printed with a candidate's name, and given to the voter by an agent outside, the only conditions being that the bulletin shall be "sur papier blanc, sans signes extérieurs, et préparé en dehors de l'assemblée." The total number of votes given (there being only one member in each electoral district) is checked by reference to "la feuille d'appel et inscription des votants," the law still supposing that each voter is publicly called on to vote. If the voter, when challenged, cannot sign his polling-card, he may call a witness to sign for him. The following classes of bulletins are rejected:—"illisibles, blancs, ne contenant pas une désignation suffisante; sur lesquels les votants se sont fait connaître; contenant le nom d'une personne n'ayant pas prêté le serment prescrit" (i.e. of a person not nominated). Only the votes pronounced bad by the bureau in presence of representative scrutineers are preserved, in case these should be called for during the "Session pour vérification des Pouvoirs." Practically the French ballot did not afford secrecy, for you might observe what bulletin the voter took from the agent, and follow him up the queue into the polling-place; but the determined voter might conceal his vote even from the undue influence of government by scratching out the printed matter and writing his vote. This was always a good vote and scrutiny of good votes was impossible. The ballot is still used in the elections to the National Assembly, but in the Assembly itself only in special cases, as e.g. in the election of a "rapporteur." Under the law of 10th August 1871 the conseils généraux (departmental councils) are elected by ballot.
In Piedmont the ballot formed part of the free constitutional government introduced by Charles Albert in March 1848; it was extended to Italy in 1861. Voting for the Italian chamber of deputies takes place under the law of 20th November 1859, and in public halls (not booths), to which admission is gained by showing a certificate of inscription, issued by the mayor to each qualified voter. A stamped blue official paper, with a memorandum of the law printed on the back (bolletino spiegato), is then issued to the elector; on this he writes the name of a candidale (there being equal electoral colleges) or, in certain exceptional cases, gets a confidential friend to do so, and hands the paper folded-up to the president of the bureau, who puts it in the box (urna), and who afterwards presides at the public "squittinio dei suffragi." Greece is the only European country in which the ball-ballot is used. The voting takes place in the churches, each candidate has a box on which his name is inscribed, one half (white) being also marked "yes," the other half (black) "no." The voter, his citizenship or right to vote in the eparchy being verified, receives one ball or leaden bullet for each candidate from a wooden bowl, which a clerk carries from box to box. The voter stretches his arm down a funnel, and drops the ball into the "yes" or "no" division. The vote is secret, but there is apparently no check on "yes" votes being given for all the candidates, and the ball or bullet is imitable.
The earlier history of the ballot in Hungary is remarkable. Before 1848 secret voting was unknown there. The electoral law of that year left the regulation of parliamentary elections to the county and town councils, very few of which adopted the ballot. The mode of voting was perhaps the most primitive on record. Each candidate had a large box with his name superscribed and painted in a distinguishing colour. On entering the room alone the voter received a rod from 4 to 6 feet in length (to prevent concealment of non-official rods on the voter's person), which he placed in the box through a slit in the lid. By the electoral law of 1874 the ballot in parliamentary elections in Hungary was abolished, but was made obligatory in the elections of town and county councils, the voting being for several persons at once.
In Prussia, Stein, by his Städteordnung, or municipal corporation act of 1808, introduced the ballot in the election of the municipal assembly (Stadtverordnetenversammlung). Under the German constitution of 1867, and the new constitution of the 1st of January 1871, the elections of the Reichstag were to be conducted by universal suffrage under the ballot in conformity with the electoral law of the 31st of May 1869.
America.—At the first elections in America voting was viva voce; but several of the colonies early provided for the use of written or printed ballots. By 1775 ballots were used in the New England states, in Pennsylvania, Delaware, North Carolina and South Carolina; they were introduced in New Jersey in 1776, and in New York in 1778, so that, at the time the constitution of the United States was adopted, viva voce voting prevailed at public elections only in Maryland, Virginia and Georgia. Of the new states which later entered the Union, only Illinois, Kentucky, Missouri and Arkansas did not have a ballot system when they became states. During the first half of the 19th century, Maryland, Georgia, Arkansas (1846) and Illinois (1848) adopted the ballot. In Missouri ballot-voting was introduced to some localities in 1845, but not until 1863 was it generally adopted in that state. Virginia did not provide for voting by ballot until 1869, and in Kentucky viva voce voting continued until 1819, but while the use of ballots was thus required in voting, and most of the states had laws prescribing the form of ballots and providing for the count of the vote, there was no provision making it the duty of any one to print and distribute the ballots at the polling-places on election day. In the primitive town meetings ballots had been written by the voters, or, if printed, were furnished by the candidates. With the development of elections, the task of preparing and distributing ballots fell to political committees for the various parties. The ballot-tickets were thus prepared for party-lists of candidates, and it was not easy for any one to vote a mixed ticket, while, as the voter received the ballot within a few feet of the polls, secrecy was almost impossible, and intimidation and bribery became both easy and frequent.
Soon after the adoption of the Australian ballot in Great Britain, it was introduced in Canada, but no serious agitation was begun for a similar system in the United States until 1885. In 1887 bills for the Australian ballot were actively urged in the legislatures of New York and Michigan, although neither became law. A Wisconsin law of that year, regulating elections in cities of over 50,000 population, incorporated some features of the Australian system, but the first complete law was enacted by Massachusetts in 1888. This Massachusetts statute provided for the printing and distribution of ballots by the state to contain the names of all candidates arranged alphabetically for each office, the electors to vote by marking the name of each candidate for whom they wished to vote. At the presidential election of 1888 it was freely alleged that large sums of money had been raised on an unprecedented scale for the purchase of votes, and this situation created a feeling of deep alarm which gave a powerful impetus to the movement for ballot reform. In 1889 new ballot laws were enacted in nine states: two states bordering on Massachusetts, Connecticut and Rhode Island; four states in the middle-west, Indiana, Michigan, Wisconsin and Minnesota; two southern states, Tennessee and Missouri; and Montana, in the far west. The Connecticut law, however, marked but little improvement over former conditions, since it provided only for official envelopes in which the unofficial party ballots should be voted. The Indiana law provided for a single or "blanket" ballot, but with the names of candidates arranged in party-groups, and a method of voting for all of the candidates in a party-group by a single mark. Michigan and Missouri also adopted the party-group system. The other states followed the Massachusetts law providing for a blanket ballot with the candidates arranged by offices.
The new ballot system had its first practical demonstration at the Massachusetts election of 1889, and its success led to its rapid adoption in many other states. In 1890 ballot laws were passed in seven states: Vermont, Mississippi, Wyoming and Washington provided for the Massachusetts plan, although Vermont afterwards adopted the system of party-groups, which Maryland used from the first. The New York and New Jersey laws of 1890, however, only provided for official ballots for each party, and allowed ballots obtained outside of the polling-booths to be used. In 1891 seventeen additional states and two territories adopted the Australian ballot system. All of these provided for a blanket ballot; but while the Massachusetts arrangement was adopted in Arkansas, Nebraska, New Hampshire, North and South Dakota, Kentucky, Texas and Oregon, the system of party groups was followed in Colorado, Delaware, Illinois, Maine, Ohio, Pennsylvania and West Virginia. California had the Massachusetts arrangement of names, but added on the ballot a list of party names, by marking one of which a voter would cast his vote for all of the candidates of that party. Pennsylvania placed all the candidates not in a party-group in alphabetical order.
Iowa adopted the Australian ballot system in 1892; Alabama and Kansas in 1893; Virginia in 1894; Florida in 1895; and Louisiana and Utah in 1896. In 1895, too, New York adopted the blanket ballot in place of separate party ballots, but arranged the names of candidates in party columns. The only state to abandon the blanket ballot after once adopting it was Missouri which in 1897 returned to the system of separate ballots, with no provision for booths where the ballot might be marked in secret. (See the article, "Present Status of the Ballot Laws," by Arthur Ludington in Amer. Pol. Science Rev. for May 1909.)
Owing to the large number of officials chosen at one time in American elections, the form and appearance of the ballot used is very different from that in Great Britain. At the quadrennial presidential election in New York state, for example, the officers to be voted for by each elector are thirty-six presidential electors, one congressman, state-governor, lieutenant-governor and five other state officers, a member for each house of the state legislature, several judges, a sheriff, county-clerk and other county officers. The column with the list of the candidates of each party for all of these offices is 2 to 3 ft. in length; and as there are often eight to ten party-tickets in the field, the ballot-paper is usually from 18 to 20 in. in width. Each voter receives one of these "blanket" ballots on entering the polling-place, and retires to a booth to mark either a party column or the individual candidates in different columns for whom he wishes to vote. Where, as in Massachusetts, the names of candidates are arranged by offices instead of in party-lists, every voter must mark the name of each individual candidate for whom he wishes to vote. Connecticut, New Jersey, Missouri, North and South Carolina, Georgia and New Mexico use the system of separate party ballots. (See also Voting, Voting Machines, Election, Representation.)
1 ^ For a description of Grote's card-frame, in which the card was punctured through a hole, and was thus never in the voter's hands, see Spectator, 25th February 1837.
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A Blog Around The Clock
New and Exciting in PLoS ONE
Radiographs Reveal Exceptional Forelimb Strength in the Sabertooth Cat, Smilodon fatalis:
The sabertooth cat, Smilodon fatalis, was an enigmatic predator without a true living analog. Their elongate canine teeth were more vulnerable to fracture than those of modern felids, making it imperative for them to immobilize prey with their forelimbs when making a kill. As a result, their need for heavily muscled forelimbs likely exceeded that of modern felids and thus should be reflected in their skeletons. Previous studies on forelimb bones of S. fatalis found them to be relatively robust but did not quantify their ability to withstand loading. Using radiographs of the sabertooth cat, Smilodon fatalis, 28 extant felid species, and the larger, extinct American lion Panthera atrox, we measured cross-sectional properties of the humerus and femur to provide the first estimates of limb bone strength in bending and torsion. We found that the humeri of Smilodon were reinforced by cortical thickening to a greater degree than those observed in any living felid, or the much larger P. atrox. The femur of Smilodon also was thickened but not beyond the normal variation found in any other felid measured. Based on the cross-sectional properties of its humerus, we interpret that Smilodon was a powerful predator that differed from extant felids in its greater ability to subdue prey using the forelimbs. This enhanced forelimb strength was part of an adaptive complex driven by the need to minimize the struggles of prey in order to protect the elongate canines from fracture and position the bite for a quick kill.
Is Thermosensing Property of RNA Thermometers Unique?:
A large number of studies have been dedicated to identify the structural and sequence based features of RNA thermometers, mRNAs that regulate their translation initiation rate with temperature. It has been shown that the melting of the ribosome-binding site (RBS) plays a prominent role in this thermosensing process. However, little is known as to how widespread this melting phenomenon is as earlier studies on the subject have worked with a small sample of known RNA thermometers. We have developed a novel method of studying the melting of RNAs with temperature by computationally sampling the distribution of the RNA structures at various temperatures using the RNA folding software Vienna. In this study, we compared the thermosensing property of 100 randomly selected mRNAs and three well known thermometers – rpoH, ibpA and agsA sequences from E. coli. We also compared the rpoH sequences from 81 mesophilic proteobacteria. Although both rpoH and ibpA show a higher rate of melting at their RBS compared with the mean of non-thermometers, contrary to our expectations these higher rates are not significant. Surprisingly, we also do not find any significant differences between rpoH thermometers from other -proteobacteria and E. coli non-thermometers.
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The Rock and Roll Hall of Fame + Museum
Studying the music of Woody Guthrie along with John Steinbeck’s The Grapes of Wrath will enhance students’ understanding of both works and of the historical conditions which produced them. Students will see how these artists drew inspiration from the common people and how both attempted to use their art as agents of social change.
Students will:
1. Recognize thematic parallels between Woody Guthrie’s music and Steinbeck’s novel;
2. Develop an appreciation for The Grapes of Wrath and the music of Woody Guthrie, as works of art and historical documents;
3. Explore the idea of the “American spirit.”
CDs/tapes/records of Guthrie songs; lyrics to “This Land Is Your Land;” Steinbeck’s The Grapes of Wrath; video (optional).
Suggested for high school English or social studies students, grades 10-12.
2-3 class periods in addition to periods already devoted to study of novel.
1. Read Steinbeck’s The Grapes of Wrath.
2. Introduce music and life of Woody Guthrie, considering the following quote:
Possibly show video Hard Travelin’: Woody Guthrie (MGM/UA release 60084 - 70 min.) or read excerpts from Bound for Glory, Guthries’ autobiography. Play some Guthrie songs. Discuss the parallels between Guthrie’s life and music and the experience of the Joad family. How well does Tom Joad fit Steinbeck’s description of Guthrie? How does Tom change over the course of the novel?
3. Distribute lyrics of “This Land Is Your Land.” Play song, focusing student attention on the last several (relatively unknown) verses. Discuss connections between the song and the novel considering the following:
• Use of irony (e.g. beauty of land vs. condition of people)
• Attitude toward the land
• Idea of the “American spirit”
• Political implications/views
Drawing on their knowledge of the Steinbeck’s novel and the music and life of Woody Guthrie, students should be able to complete the following writing assignment. Imagine that Tom Joad meets Woody Guthrie. Write a short scene in which you:
• describe the setting and circumstances of the meeting
• develop a brief dialogue between the two characters
Scene will be evaluated based on the plausibility of the meeting and dialogue as well as on dramatic elements such as characterization, etc.
Listen to songs from Bruce Springsteen’s 1995 album The Ghost of Tom Joad. Why would Springsteen use that allusion? Comment on the influence of Woody Guthrie.
How do later singers such as Pete Seeger and Bob Dylan carry on the efforts of Woody Guthrie? Are there writers during the 1960s whose themes have been influenced by Steinbeck?
Consider the writings of Frederick Jackson Turner and his idea of the “rugged individual” in light of the music of Woody Guthrie and the writings of John Steinbeck.
Selected Recordings
A Legendary Performer (RCA, 1977)
The Greatest Songs of Woody Guthrie (Vanguard, 1988)
Dust Bowl Ballads (Rounder, 1988)
Further Reading
Guthrie, Woody. Bound for Glory. New York: Dutton, 1943.
Hard Travelin’: Woody Guthrie (MGM/UA release 600884) - 70 min. video
Klein, Joe. Woody Guthrie: A Life. New York: Knopf, 1980.
Lomax, Alan, Woody Guthrie and Pete Seeger. Hard Hitting Songs for Hard-Hit People. New York: Music Sales, 1967.
The Woody Guthrie Songbook. New York: Woody Guthrie Publications, 1976.
Woody Guthrie
Woody Guthrie (1912- 1967) used the American folk song as a form of social protest. Drawing his inspiration from the people, Guthrie wanted his music to appeal to all races and creeds. He wrote nearly 1,000 songs, many of them new words put to old tunes. His songs, in a hillbilly singing style, are about social justice, the American Dream and the trials and tribulations of everyday life.
Born Woodrow Wilson Guthrie in Okemah, Oklahoma, Guthrie left home at 16 with his harmonica and traveled through Texas and Louisiana. During a visit to his Uncle Jeff Guthrie in Pampa, Texas Guthrie learned how to play chords on the guitar. During the Dust Bowl of the 1930s, Guthrie, like many others headed towards California looking for food, shelter, and a job. After riding the rails as a hobo, he finally found work in Los Angeles hosting a radio show on KFVD. He also wrote a daily column for the communist newspaper, The People’s Daily World. Guthrie’s first-hand knowledge of life on the road and the plight of the migrant worker caused him to be a supporter of organized labor and other left-wing political causes.
At the start of World War II Guthrie moved east to New York. He wrote anti-Hitler songs and had a sign on his guitar saying “This Machine Kills Fascists.” From 1943- 1945 Guthrie was with the merchant marines. He wrote “This Land Is Your Land” after the war in response to a wartime favorite, the patriotic “God Bless America.” During the McCarthy era of the 1950s, Guthrie’s songs were labeled “un-American.”
Guthrie’s fame grew throughout the years. His songs, however, were not recorded until 1940. Guthrie had a tremendous influence on Pete Seeger, Bob Dylan, and the folk revival of the 1950s. He went on the road with Seeger singing in support of organized labor. Seeger also organized a series of memorial concerts for Guthrie in the late Sixties and early Seventies. In 1976 Guthrie’s autobiography, Bound for Glory, was made into a motion picture.
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Write a single statement that will print the message "first is " followed by the value of first, and then a space, followed by "second = ", followed by the value of second. Print everything on one line and go to a new line after printing. Assume that first has already been declared as a double and that second has been declared as an int. Assume also that the variables have already been given values.
Best answer:
Answers (8)
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"url": "http://www.chegg.com/homework-help/questions-and-answers/write-single-statement-print-message-first-followed-value-first-space-followed-second-foll-q3510486"
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The brainy one, Tarchia (1977)
Phylum : Chordata
Class : Reptilia
Order : Ornithischia
Family : Ankylosauridae
Subfamily : Ankylosaurinae
Genus : Tarchia
Species : T. kielanae
• Late Cretaceous (75 - 65 Ma)
• 8,5 m long and 4 500 kg (size)
• Barun Goyot formation, Mongolia (map)
Estimated at over eight meters long, Tarchia is one of the largest ankylosaurids currently known, rivalling even the more famous Ankylosaurus. In fact given that Ankylosaurus is still known only from partial remains, Tarchia may one day actually prove to be the biggest. Tarchia was named along with another large, but slightly smaller ankylosaurid called Saichania, and although quite similar to one another, there are a number of identifiable differences between the two, particularly differences associated with the skull proportions. Despite these differences however, both Tarchia and Saichania both share bulbous bone growths that are present across the tops of their skulls. A North American ankylosaurid called Nodocephalosaurus also has these bumps, strongly suggesting a possible relationship with Tarchia and Saichania.
Tarchia possessed a wide cropping beak across its mouth that allowed large amounts of vegetation to be indiscriminately pulled into the mouth. These plants would have likely been quite tough considering that Tarchia lived in an arid climate that was near desert in places, and would have required a large degree of processing in the mouth. Evidence for this comes from the teeth which show occlusion wear, basically meaning that the teeth of the upper and lower jaws regularly made contact. Like other ankylosaurids Tarchia had teeth more suited to chopping, and with every up and down movement of the jaw, the food in the mouth would be chopped into smaller and smaller pieces. This was not just to help swallowing but to increase the efficiency of digestion as the teeth chopping the food would provide a greater surface area to be exposed to the digestive acids of the stomach, greatly enhancing the nutritional gain.
Tarchia also had a hard palate and a network of air passages in the snout which would have helped to moisten the dry air of its ecosystem before it reached its lungs. This would greatly reduce the amount of water lost through the process respiration, a vital adaptation considered the climate that Tarchia lived in. Additionally the presence of the hard palate (unknown in most dinosaurs, but seemingly common in ankylosaurids) meant that Tarchia could still breathe while it processed food in its mouth.
Anserimimus planinychus
Source: http://dinosaurs.wikia.com/wiki/Anserimimus
Name: Anserimimus planinychus
Name Meaning: Goose Mimic
First Described: 1988
Described By: Barsbold
ClassificationDinosauria, Saurischia, Eusaurischia, Theropoda, Neotheropoda, Averostra, Tetanurae, Orionides, Avetheropoda, Coelurosauria, Tyrannoraptora, Maniraptoriformes, Ornithomimosauria, Ornithomimidae, Ornithomiminae
Anserimimus is a more advanced ornithomimid dinosaur from the Nemegt Formation in Bayankhonger Province, Mongolia. Anserimimus lived in the early Maastrichtian age of the Late Cretaceous, about 70 million years ago. It was a relatively small ornithomimid, only about 3 meters long. Even though Anserimimus does not specifically resemble geese, ornithomimosaurs have long been named for different species of birds. It is known from only one skeleton, making it relatively unknown. It was very closely related to Gallimimus. It lived alongside Tarbosaurus, Deinocheirus, Barsboldia, Saurolophus, Tarchia, dromaeosaurids, oviraptorosaurs, troodontids, birds, titanosaurs, and pachycephalosaurians. It lived amongst stream and river channels, mudflats, and shallow lakes. It was probably an omnivore and is distinguished from other ornithomimosaurs by its extremely powerful arms and almost straight claws. What the arms were for is still unknown.
Shout out goes to jagannaths!
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Lesson Plan
The Other Side of Fort Pulaski: Walking Tour Outside the Fort
Blended photo showing modern fort and old battle damage.
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Grade Level:
Third Grade-Eighth Grade
Biology: Animals, Biology: Plants, Civil War, Conservation, Ecology, Engineering, Environment, Geography, History, Landscapes, Military and Wartime History, Social Studies
30-60 minutes
Group Size:
60 or more
in the park
National/State Standards:
Georgia Performance Standards/Common Core
Science S3L1, S5E1, S6E3
Social Studies SS4G2, SS5H1, SS8H6, SS8G1
Civil War
This is a teacher-led activity to be done on site at the fort. The teacher will lead a walk around the outside of the fort to show students dramatic battle damage from the Civil War battle, including projectiles that are still lodged in the brick walls. It also highlights the salt marsh ecology on Cockspur Island, and shows how human influence has repeatedly changed the island’s environment over time.
1) Describe the damage to the fort during the 1862 battle.
2) Explain why the National Park Service has not repaired that damage.
3) Explain why trees did not grow on cockspur Island in its natural state.
4) Name at least two actions taken by humans that have altered the environment on Cockspur Island.
Due to its strategic location at the mouth of the Savannah River, Cockspur Island has served as a military post since the 18th century. Humans have continually modified the island's natural ecology to serve the needs of society. In its natural state, the island is a salt marsh, with high tides covering the island twice daily. Only a few, very specialized plants (excluding trees) can grow in that harsh environment. Much of the island was in that natural state during the Civil War era, when Fort Pulaski was an active military post. In the years since then, the military gave up the fort and the nearby Savannah River was repeatedly dredged for ever larger cargo ships. For many years, the river mud from dredging was dumped on the island, eventually raising parts of the island above high-tide line and permitting additional vegetation, including trees, to flourish on the island.
A dialog between teacher and students at each stop should enable the teacher to assess the students' learning in this lesson.
Preservation--the process of protecting something valuable so that it is not damaged or destroyed.
Salt marsh--a flat area of land, frequently covered by salt water, where only a few, specialized types of plants can grow.
Dike--an embankment of earth used to protect an area from flooding.
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"url": "https://www.nps.gov/fopu/learn/education/classrooms/self-guided-outside-fort-tour.htm"
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Production and Distribution
Most coca is grown in Colombia, Peru, and Bolivia. The farmers, for whom it is a relatively well-paying crop, harvest and dry the leaves, which are then processed into coca paste. Cocaine base is extracted from the paste in informal laboratories. Further processing produces cocaine hydrochloride, a white powder, which is exported. Once in the United States, the cocaine is cut (diluted) with ingredients such as lactose, and sold or further processed into crack.
Import and production have been controlled by enormously powerful cartels such as the Medellín and Cali cartels in Colombia; the highly armed cartels have infiltrated governments and corrupted officials and have been held responsible for assassinations of public officials. Drug trafficking reached the highest levels of government and was at least in part responsible for the U.S. invasion of Panama in 1989 and the arrest and subsequent conviction of Panama's de facto leader, Manuel Noriega.
See more Encyclopedia articles on: Pharmacology
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"url": "http://www.factmonster.com/encyclopedia/science/cocaine-production-distribution.html"
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In November 2010, ten months after a magnitude 7.0 earthquake flattened huge sections of Port-au-Prince, Haiti, a team of geologists commissioned by the United Nations set out to make the first detailed soil map of the city. Armed with sledgehammers and vibration sensors, the scientists surveyed how soils throughout Port-au-Prince either amplify or muffle seismic vibrations. The resulting map can now be used to guide reconstruction efforts. In this Science Bulletins feature, learn how geologists and engineers in Haiti and San Francisco are improving our resilience to powerful shifts of Earth's crust.
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"fasttext_score": 0.2998993992805481,
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"language_score": 0.8907526135444641,
"url": "http://www.amnh.org/explore/science-bulletins/earth/documentaries/on-shaky-ground-building-a-safer-future-in-haiti/synopsis"
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A weight-loss vaccine has shown promise in early tests. The shot suppresses the hormone ghrelin, which stimulates appetite and slows metabolism. Both obese mice and mice at healthy weights that received the vaccine had significant decreases in food intake and increases in calorie burning compared with unvaccinated mice. One reason diets fail is that they trigger a rise in ghrelin; the vaccine should block this effect, making it easier to lose weight and keep it off, says study coauthor Mariana P. Monteiro, associate professor of human anatomy at the University of Porto in Portugal. She estimates that human testing will begin in two to three years, and that the vaccine's effects could last about four years. Ghrelin has other functions in the body besides energy regulation—such as stimulating growth hormone, which plays a role in learning and memory—so, for safety, the vaccine is designed to reduce ghrelin but not completely abolish it, Monteiro adds.
See Also
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"language": "en",
"language_score": 0.9557737708091736,
"url": "http://www.allure.com/story/weight-loss-shot"
}
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The son of portraitist Charles Willson Peale, Rembrandt Peale's natural talents had been developed by his father and honed from many hours of copying portraits in Charles Willson Peale's museum. Born on February 22, 1778, Rembrandt Peale shared his birthday with George Washington. His first encounter with George Washington took place on July of 1787.
Washington posed for Charles Willson Peale while in Philadelphia attending the Constitutional Convention. Relying on a long association, Peale approached Washington on his son's behalf in 1795, and the President agreed to three sittings of three hours each, from seven to ten in the morning.
By the time Washington arrived for the first sitting, it was agreed that Charles Willson Peale would provide a reassuring presence, sparing Rembrandt the need to talk and paint at the same time. Rembrandt Peale's life study revealed an aging George Washington of sixty-three whose firmly set mouth and skeptical eyes gave his expression a somewhat dour cast. The young artist succeeded in capturing the grandeur of his subject; the force of the gaze and the line of the jaw hint at the determination and the sheer physical presence of Washington. After the third and final sitting with Washington in 1795, Rembrandt Peale hurried off to Charleston, South Carolina, where he made at least ten copies of his portrait.
For years Peale was haunted by his desire to present an inspiring, grandiose image of Washington. Peale knew that the man he had painted in 1795, worn down by the presidency was no longer the commanding presence of the years of the Revolution. Peale was determined to create a likeness of Washington that would transcend representational accuracy, to convey the heroic qualities that Washington produced in the minds of many Americans. It was this ideal Washington that Peale felt he had fallen short of in each new portrait he attempted. Peale's family began to believe him obsessed, perhaps dangerously so and his father told him bluntly that the task was impossible.
Nevertheless, in 1823 Peale decided to make one last effort. Peale was inspired by many different sources, including the works of his father and the bust portrait by Jean-Antoine Houdon. What Peale created, however, was something quite different, an image of Washington that was as much icon as likeness. Peale painted Washington in bust pose, facing left and framed by the massive stone oval that gave rise to the title "Porthole" portrait. Beyond the subject's head and shoulders drifted the clouds of some republican Olympus.
For weeks following the completion of the portrait, Peale's studio was crowded with hundreds of visitors eager for a glimpse of what was already said to be a remarkably faithful likeness of George Washington. The artist himself was anxious to solicit the opinions of men who had actually known Washington and soon collected a series of glowing endorsements that he later copied into his memoir, including from Washington's nephew Bushrod Washington and Chief Justice John Marshall. In 1832, Peale sold the original Porthole portrait to Congress for the rather significant sum of two thousand dollars. It still hangs today in the old Senate Chamber of the United States Capitol.
Howard, Hugh. The Painter's Chair: George Washington and the Making of American Art. New York: Bloomsbury Press, 2009.
Miller, Lillian B., Carol Eaton Hevner. In Pursuit of Fame: Rembrandt Peale, 1778-1860. Seattle: University of Washington Press, 1992
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Escargot may be known as a French delicacy, but it was ancient humans living in modern-day Spain that ate roasted snails thousands of years ago.
According to archaeologists, Paleolithic humans living in caves in southern Spain ate roasted land snails around 30,000 years ago. The discovery comes as a team was investigating remains at the Cova de la Barriada site. They found snails made up a decent portion of the diet of these early humans.
“Large accumulations of snails were discovered in shallow pits at the site. Our investigations determined that these had been roasted – the earliest evidence to show that snails had formed part of the human diet,” said Javier Fernandez-Lopez de Pablo, of the Tarragona-based Institut Catala de Paleoecolgia Humana i Evolucio Social (IPHES) according to Telegraph.
The team ended up finding hundreds of burnt snail shells in several fireplaces, along with tools.
The roasted snails aren’t thought to have made up a significant portion of the ancient humans’ diet, but they were good sources of several vitamins including vitamin A and B12.
The study, published in this week’s Plos One, shows snails were eaten in Spain long before other sites throughout the Mediterranean.
As for why snails suddenly became a food staple, researchers aren’t sure yet. Humans were changing quite a bit around this time. Larger gatherings of people could have prompted them to look for additional food sources.
Whatever the case, people today can feel comfortable adding snails to their paleo diets. Now eating like a caveman includes at least one delicacy.
Image credit: DeviantArt
Follow News Ledge
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"url": "https://www.newsledge.com/add-snails-paleo-diet-ancient-spanish-cavemen-first-eat-snails/"
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Thomas- Renaissance
Who was a powerful ruler of Florence who valued education and culture? Cosimo de' Medici
What is Miguel de Cervantes best know for? Don Quixote
Machiavelli wanted to have an effect on ________ politics
Why did people support Martin Luther? They were unhappy with church practices
How did women in noble families help spread Renaissance ideas? girls were taught arts, philosophy, and literature at home, and some women gained political power
How are classical and Renaissance statues alike? Both feature realistic and lifelike poses
How did the French king made peace between the Huguenots and the Catholics? The kind allowed Protestants to remain in France in certain towns.
Why was the Catholic religion strong in spain? People who were not Catholic were thrown out, converted, or killed
Created by: thomasja
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"url": "http://www.studystack.com/flashcard-895599"
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If proteins could talk, what would they say? Josiah Zayner still doesn't know — but he does have a sense of what they'd want to sing. That's because Zayner has developed a new musical instrument that relies on infinitesimally small plant proteins to produce melodies.
Zayner, who recently completed a PhD in biophysics at the University of Chicago, has long been interested in merging biology with electronic interfaces. The driving force behind his instrument, called the chromochord, was a desire to harness "these incredible proteins that power our lives every single day, but that nobody can see and that nobody really thinks about," he says. "I want people to experience those somehow."
To create the chromocord, which he started working on in 2011, Zayner used what are known as LOV proteins — put simply, plant proteins that are sensitive to light. These particular proteins, for instance, are behind the phenomenon whereby a plant will gravitate in the direction of a shining beam of sunlight. Having studied LOV proteins while obtaining his PhD, Zayner was well-versed in their mechanisms, and decided to utilize those isolated from oats for his chromochord.
"It's much, much harder to play than it was to make."
The instrument itself contains 12 vials of oat proteins, with the samples in each vial engineered to respond slightly differently to stimulation from light. When blue LED light strikes a vial, a spectrophotometer inside the instrument measures the protein's reactions. The device then transmits that data to software that's programmed to convert the information into sounds. Of course, the proteins themselves don't actually make noise — Zayner is essentially translating their reactions to stimulus into music.
Each vial in the chromochord can be linked to a different sound, like bells, drums, or piano. By pushing various buttons, Zayner is able to control how much light a given vial is exposed to — which then determines the note that'll be played. That process is outlined in the above video, which Zayner created for The Verge, along with a performance (at 3:52, after Zayner drinks a gin and tonic). "It wasn't easy to develop," Zayner says of the chromochord, currently in its second iteration. "But trust me, it's much, much harder to play than it was to make."
Microscopic musical protégé
Zayner has been working with Francisco Castillo Trigueros, a composer, to create complex musical arrangements using the instrument. And though he's still perfecting the chromochord, Zayner has already set his sights on yet another microscopic musical protégé: human cells. Earlier this week, he launched an IndieGoGo campaign to raise $20,000 for the development of an instrument that would elicit sounds from cultured skin cells. By exposing those cells to sounds, Zayner anticipates, he'll catalyze a reaction in the cell's ion channels that can be translated into a musical response. "The idea, really, is to eventually culture my own cells," he says. "So that I can be in a band with myself."
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Apollo (butterfly)
From Wikipedia, the free encyclopedia
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Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Lepidoptera
Family: Papilionidae
Genus: Parnassius
Species: P. apollo
Binomial name
Parnassius apollo
(Linnaeus, 1758)
The Apollo or Mountain Apollo (Parnassius apollo), is a butterfly of the Papilionidae family.
This species is of interest to entomologists due to the variety of subspecies, often only restricted to a specific valley in the Alps. The beautiful Apollo butterfly has long been prized by collectors, who aim to possess as many of the variants as possible. While over-collecting is believed to have caused populations to decline in some areas, such as in Spain and Italy, habitat change is thought to be a far more significant threat to this species’ survival.[1] Plantations of conifers, the succession of suitable habitat to scrubland, agriculture, and urbanization have all reduced the habitat of the Apollo butterfly. Climate change and acid rain have also been implicated in this species decline in Fennoscandia. In addition, motor vehicles have been cited as a cause of Apollo butterfly mortalities; vehicles on a motorway system near Bozen in South Tyrol, Italy, are said to have nearly wiped out a race of the Apollo.[1]
In Finland, the Apollo was one of the first species of insects declared endangered. The Apollo population in Finland and Sweden decreased drastically during the 1950s. The reason for this is not known, but it is commonly thought to be because of a disease. In Sweden, it is now restricted to areas that have limestone in the ground, suggesting that the decrease could hypothetically be related to acid rain.[2]
Laws exist to protect the Apollo butterfly in many countries. The Apollo is on the IUCN Red List of Threatened Animals,[3] in Appendix II in CITES .[1][4] and is mentioned in annex IV of Habitats Directive. It is protected in other states: the Principality of Liechtenstein, Czech Republic (as critically threatened species in Czech code, Decree for implementation, No. 395/1992 Sb., and No. 175/2006 Sb.), Turkey and Poland.
However, these laws focus on the protection of individuals, rather than their habitat, and so may do little to mitigate the greatest threat that populations face.[1] Fortunately, there are a number of projects specifically working to save this Vulnerable insect. A conservation programme in Pieniny National Park saved a subspecies of the Apollo butterfly that had declined to just 20 individuals in the early 1990s, through a combination of captive breeding and habitat protection.[5] In south-west Germany, conservationists are working with shepherds to ensure favourable conditions for the butterfly, which share their grassland habitat with sheep. For example, grazing periods have been shifted to avoid the Apollo butterfly larvae stage, which is vulnerable to being trampled.[6]
Description and ecology[edit]
Parnassius apollo
It is white with two red, black-edged "eye marks" on its wings. The Apollo butterfly (Parnassius apollo) is a beautiful white butterfly, decorated with large black "eye" spots on the forewings and red eye-spots on the hindwings.[7] These striking red eye-spots can vary in size and form depending on the location of the Apollo butterfly, and the bright red colour often fades in the sun, causing the eye-spots of older individuals to appear more orange.[1] The wings are shiny, with slightly transparent edges,[4] and some individuals are darker (melanistic); a general phenomenon common in many butterflies. The caterpillars of this species are velvety black with orange-red spots along the sides.[7] As well as being a great deal of individual variation in the appearance of the Apollo butterfly, a number of subspecies have also been described.[8]
Adult Apollo butterflies are seen on the wing in mid-summer,[4] feeding on nectar produced by flowers.[9] The females lay eggs, which over-winter and hatch in spring the following year.[1] The resulting caterpillars feed on stonecrop (Sedum species) and houseleek (Sempervivum species).[7] When the caterpillar is fully-grown it will pupate on the ground, forming a loose cocoon from which the adult butterfly emerges following metamorphosis.[4]
Related species can be found all over the world. The "Small Apollo" (Parnassius phoebus) is found in the high mountains while the Clouded Apollo (Parnassius mnemosyne) lives in the valleys. The Apollo caterpillar lives on larkspur and rock plants and is a velvety blue-black with small orange spots.
Distribution and habitat[edit]
Habitat of Parnassius apollo. La Thuile, Italy at abt. 2700 a.s.l.
This typically mountain species prefers flowery meadows and pastures of the continental European mountains, in Spain, Scandinavia and Central Europe, in the Balkans up to northern Greece and in the Alps between Italy and France.
It is also present in some areas of the central Asia. Typical of high altitudes, its range is from 400 metres (1,300 ft) up to 2,300 metres (7,500 ft), although it is far more present above 1,000 metres (3,300 ft).
This species requires specific climatic conditions (cold winter, sunny summer). It also requires wide open spaces (with a cover of shrubs less than 5%) and a large surface of lawns (at least 50%). The presence of the host plant for the caterpillars is critical.
Predation and Defensive Strategy[edit]
The Apollo butterfly shares a variety of defensive strategies with quite a few species of butterflies. Even from a young age larva exhibit camouflage by being entirely black. This solid color helps them avoid detection even at a close distance. However, as they mature, they do lose this advantage by developing two rows of orange dots. These dots greatly decrease the amount of crypsis.[10]) In addition to this larval camouflage, the larva also shares in a form of Mullerian mimicry with a type of millipede, glomeris guttata. Both insects share the characteristic orange spots and black body and a common habitat. The millipedes and caterpillars secrete a foul smelling odor to repel predators.[10]
Once the butterfly completes its metamorphosis,it still has a number of defensive mechanisms in place to avoid predation. One of the most easily identifiable traits is the bright eyespots found on the wings. These eyespots are essentially concentric circle of a wide variety of colors. Apart from the wide range of colors, eyespots are very limited in their plasticity. There are three main hypothesis to why these spots may have developed; they resemble the eyes of an enemy of the predator in order to intimidate them, they draw the attention of the predator to less vital components of the butterfly’s body, or the spots are there simply to surprise the predator. The only disadvantage to these spots is that they cause the butterfly to be a great deal more conspicuous.[11]
A less obvious form of defense is the actual taste of the butterfly. Similar to the monarch butterfly, the Apollo butterfly produces a repulsive taste to its predator. The butterfly seems to get this foul taste from its plant host, the sedum stenopetalum. There is a bitter tasting cyanoglucoside, sarmentonsin, which is found in both the butterfly and the plant. There is a much higher concentration of sarmentonsin found in the wings as opposed to the rest of the body.[12] The high concentration found in the wings indicates that the wings of the butterfly would taste much worse comparatively. A common predator,nesting water pipits, have evolved an interesting strategy to deter the poor taste of the butterfly. It has been observed that the bird will remove the wings before consuming the body.[13] In theory, this will get rid of the poor tastingelements of the butterfly, leaving only the nutritious body.
This article incorporates text from the ARKive fact-file "Apollo butterfly" under the Creative Commons Attribution-ShareAlike 3.0 Unported License and the GFDL.
1. ^ a b c d e f Collins, N.M. and Morris, M.G. (1985) Threatened Swallowtail Butterflies of the World. IUCN, Gland, Switzerland and Cambridge, UK.
2. ^ Lars-Åke Janzon (February 7, 2009). "Mer om apollofjäril" (in Swedish). Naturhistoriska riksmuseet.
3. ^ Gimenez Dixon (1996). "Parnassius apollo". IUCN Red List of Threatened Species. Version 2009.2. International Union for Conservation of Nature. Retrieved May 11, 2006.
4. ^ a b c d Still, J. (1996) Butterflies and Moths of Britain and Europe. Harper Collins, London.
7. ^ a b c Carter, D. (2000) Butterflies and Moths. Dorling Kindersley, London.
8. ^ Smart, P. (1975) The Illustrated Encyclopedia of the Butterfly World. Hamlyn Publishing Group Ltd, London.
10. ^ a b Descimon, H., and M. Deschamps-Cottin. "A Possible Case of Mimicry in the Caterpillar of Parnassius Apollo (L.) (Lepidoptera: Papilionidae)." Linneana Belgica 15.8 (1996): 309-10. Print.
11. ^ Stevens, Martin. "The Role of Eyespots as Anti-predator Mechanisms, Principally Demonstrated in the Lepidoptera." Biological Reviews 80.04 (2005): 573.
12. ^ Nishida, R., and M. Rothschild. "A Cyanoglucoside Stored by ASedum-feeding Apollo Butterfly,Parnassius Phoebus." Experientia 51.3 (1995): 267-69.
13. ^ Hendricks, P. A. U. L."Avian predation of alpine butterflies." Journal of theLepidopterists Society 40.2 (1986): 129.
• Parnassius gallery, including many subspecies of Parnassius apollo
• Xavier Mérit and Véronique Mérit: Les Parnassius de France, textes de Xavier Mérit-Véronique Mérit et Henri Descimon, cartes de répartition, planches, et photos en nature de Luc Manil, Xavier Mérit et Bernard Turlin, bibliographies, Bulletin des Lépidoptéristes parisiens, Volume 15 (2006), n°33 (numéro thématique), Paris, septembre 2006 (56 pages).
• Pierre Capdeville, 1978–1980, Les races géographiques de Parnassius apollo, 191 p - 26 tables - maps - 24 plates in colours, Sciences Nat, Venette.
• Jean-Claude Weiss : The Parnassiinae of the World, Pt. 4, 2005, Hillside Books, Canterbury. [1]
• Edwin Möhn, 2005 Schmetterlinge der Erde, Butterflies of the world Part 23 Papilionidae XII. Parnassius apollo. Edited by Erich Bauer and Thomas Frankenbach Keltern : Goecke & Evers ; Canterbury : Hillside Books. ISBN 9783937783161
External links[edit]
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Ankole People and their Culture
Ankole, also referred to as Nkore, is one of the oldest traditional dynasties in Uganda. The Ankole kingdom is said to have been created way back in the early 15th century,
Originally, Ankole was known as Kaaro- Karungi and the word Nkore is said to have been adopted during the 17th century following the devastating invasion of Kaaro-Karungi by Chawaali, the then Omukama of Bunyoro-Kitara (Bunyoro-Kitara was one of the most powerful kingdoms in East Africa from the 16th to the 19th century).
On October 25, 1901 the word Ankole was introduced by British colonial administrators to describe the bigger kingdom which was formed by adding to the original Nkore, the former independent kingdoms of Igara, Sheema, Buhweju and parts of Mpororo by the signing of Ankole agreement.
The Ankole society was divided into two stratified castes the Bahima (nobility and pastoralists) and the Bairu (agriculturalists/peasants), who lived together peacefully and depended on each other.
The kingdom had a centralized administration system headed by the omugabe,(king) who came from the nobility Bahima clan, assisted by abakuru b’ebyanga (local chiefs) and an overall appointed enganzi (prime minister).
The people of Ankole Kingdom are called the Banyankole and they speak a language called Runyankole. The Banyankole are inhabits of the present-day districts of Mbarara, Bushenyi, Ntungamo, Kiruhura, Ibanda and Isingiro situated in western Uganda.
In Ankole, cattle were the most treasured possession in their lives; providing milk, ghee, beef and hides, cows were the state of the value and a medium of exchange. Cows were the mode of payment of bride price and some special cows were used in religious rituals as well as cultural and political ceremonies. The long horned Ankole cows were most valued because they were adapted to the climate of the region and resistant to most diseases. A cow was appreciated for the amount of milk it yielded: for its size and stature; its body color; and for the shape and whiteness of its long horns, as well as its ancestry.
Ankole people’s idea of Supreme Being was Ruhanga (creator). The abode of Ruhanga was said to be in heaven, just above the clouds, Ruhanga was believed to be the maker and giver of all things. It was, however, believed that the evil persons could use black magic to interfere with the good wishes of Ruhanga and cause ill- health, drought, death or even bareness in the land and among the people.
History of the Ankole Kingdom
Some scholars believe that Ankole originally was occupied by Bantu-speaking agricultural Bairu. Later, Ankole provided a passage for Hamitic peoples, possibly the Bahima, migrating from Ethiopia southward. These pastoralists conquered the Bairu and proclaimed themselves the rulers of the land. According to some scholars, the more numerous Bairu were serfs and the Bahima were the dominant ruling class. For the most part the two ethnic groups coexisted peacefully.
When the British created Uganda as a protectorate in 1888, Ankole was a relatively small kingdom ruled by a king (Mugabe) with supreme power. In 1901 the British enlarged the kingdom by merging it with the similarly small kingdoms of Mpororo, Igara, Buhweju, and Busongora. The power of the Omugabe was curtailed considerably once his kingdom was legally and constitutionally controlled. However, as the Omugabe of Ankole, the king was entitled to all the titles, dignities, and preeminence that were attached to his office under the laws and customs of Ankole. A political relationship based on serfdom, slavery, and clientship ceased to exist under British rule, and the Bairu became less marginalized and despised.
Ankole society evolved into a system of ranked statuses, where even among the cattle-owning elite, patron-client ties were important in maintaining social order. Men gave cattle to the king (mugabe) to demonstrate their loyalty and to mark life-cycle changes or victories in cattle raiding. This loyalty was often tested by the king’s demands for cattle or for military service. In return for homage and military service, a man received protection from the king, both from external enemies and from factional disputes with other cattle owners.
Marriage and Family
A social distinction between the Bahima and the Bairu was established by prohibiting intermarriage between them. The Bahima would find it repugnant to marry a Mwiru. Moreover, it was illegal for a Muhima to give cattle to a Mwiru. A Mwiru would have no cattle for bridewealth for a Muhima wife since all he had was unproductive cows and bull calves. Cattle were essential not only for the legitimacy of marriage but also for the legitimacy of the children born out of a marital relationship.
A woman with no children has no status among the Banyankole, and most women wish to marry and raise many children. If a woman is unable to bear children, her husband is likely to contemplate taking a second wife. Monogamy was the standard practice, though polygamy was not prohibited. Both the Mugabe and wealthy Banyankole practiced polygamy. Today monogamy remains the predominant form of marriage, influenced by Westernization, Christianity, education, and the traditional Banyankole model.
Death and Afterlife
Among the Banyankole illness is not considered a natural cause of death; therefore, such deaths require an investigation to find the responsible party. By contrast, old age is accepted as a sufficient cause for death. It is held that God allows old people to die after the completion of their time on earth. The Banyankole view death as a passage to another world.
When a man dies, every relative, along with friends and neighbors, is informed. A person who fails to attend the funeral without a good reason may be suspected of being associated with the death. Before burial, the body is washed and the eyes are closed. As the deceased is placed in the grave, the right hand is placed under the head while the left hand rests on the chest. The body lies on the right side. One or more cows are slaughtered to feed everyone present. Beer is provided as part of the mourning. The mourning goes on for four days. A deceased woman is treated in a similar manner except that in the grave she is made to lie on the left side as if she were facing her husband. Her left hand is placed under her head, while her right hand rests on her chest.
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A Blog Around The Clock
i-710d005c8660d36282911838843a792d-ClockWeb logo2.JPG This February 06, 2005 post describes the basic elements of the circadian system in mammals.
The principal mammalian circadian pacemaker is located in the suprachiasmatic nuclei (SCN) of the hypothalamus. The general area was first discovered in 1948 by Curt Richter who systematically lesioned a number of endocrine glands and brain areas in rats. The only time he saw an effect on circadian rhythms was when he lesioned a frontal part of hypothalamus (which is at the base of the brain) immediatelly above the optic chiasm (the spot where two optic nerves cross). Later studies in the 1970s narrowed the area to a small pair of nuclei, each composed of about 10,000 neurons. Similar studies (lesions) were performed in a number of other species of mammals, confirming that SCN is the pacemaker in all mammals.
i-3fe5aaeb619a1f00ce45800eb391e307-a1 Rat Brain.jpg
[Image: Rat Brain]
A serendipitous discovery of a circadian period mutant (Tau-mutant) by Martin Ralph, then in Mike Menaker’s lab, provided an opportunity to further test the hypothesis that SCN is, indeed, the pacemaker, and not just a way-station for the circadian information (as was still a possible alternative explanation of the lesion studies). The wild-type Golden hamsters have an endogenous period of almost precisely 24 hours. The homozygous tau-mutants exhibit a period of about 20 hours (while heterozygotes have an intermediate period of about 22 hours). Ralph transplantated SCNs between wild-type and Tau-mutant hamsters. What he saw was that the period of the overt rhythms of the hosts was always equal to the period of the transplanted SCN of the donor, i.e., a mutant hamster with a wild-type graft exhibited a 24-hour rhythm, while a wild-type mutant with implanted mutant SCN showed a periodicity of 20 hours. He rightly concluded that the SCN contained within itself all the information needed for the proper functioning of the circadian system, including the most basic property of the rhythm – its period – thus the SCN is, by definition, the pacemaker of the hamster circadian system.
i-25738b97873aa143f7b0dcf323d2dc6c-a2 Wild Type Hamster.jpg
Wild-Type Hamster
i-50cfedb2cf14342722b78868e6e3629d-a3 Tau Mutant Hamster.jpg
Tau-Mutant Hamster
i-5e03894fac700c33822c23776feaeac4-a4 Hamster SCN translplant.jpg
Results of Transplantations
Each SCN is, itself, a multi-oscillator system as individual SCN neurons can show different endogenous periodicities in vitro. In vivo, the individual neurons are coupled together to produce a single circadian output. Recent studies indicate that some of the coupling is not synaptic (via neurotransmitters) but electrical (via “gap junctions”). More recent studies uncovered an internal division within each nucleus in what are termed “core” and “shell”, each with slightly different properties, one with slightly shorter innate period than the other, and one recieving the majority of the neural input from the eye.
i-727d4771659c081500693c44259fb84a-a5 AVT SCN in vitro.jpg
The eye is the only route for the information about external light conditions into the mammalian circadian system. The photic (light) input to the SCN comes from the ganglion cells of the retina via a direct mono-synaptic retinohypothalamic tract (i.e., the ganglion cell of the retina sends one long process all the way to the SCN, so the signal is NOT transduced via a chain of several successive neural cells). Non-visual photoreception, involved in circadian entrainment, pupillary reflex and control of mood, appears to be mediated differently from vision. Although photoreceptor cells (rods and cones) appear to play a role, most attention recently has been given to a small subset of retinal ganglion cells that project directly to the SCN and have been shown to be directly photo-sensitive. The identity of the photopigment used by these cells remains a subject of much debate, with melanopsin and cryptochrome being the major candidates. As persuasive data have been reported supporting an important role for each of these pigments, it is likely that both are involved, playing specific yet somewhat overlapping roles in non-visual photoreception.
i-2ec8d6497698950c489335bff3919913-a6 Mammalian Retina.jpg
[Image - Mammalian Retina]
The output of the clock is coupled to various effector areas of the brain including other areas of the hypothalamus, as well as to the superior cervical ganglia which provide adrenergic innervation of the pineal gland. Driven by the daily rhythm of adrenergic stimulation, the pineal synthesizes and secretes its hormone (melatonin) into the bloodstream during the night, but not during the day. In mammals, the profile of melatonin secretion is used for the interpretation of daylength in the photoperiodic response. There is no endogenous rhythmicity in the mammalian pineal – all pineal rhythms are driven by neural inputs from the SCN. The retina, on the other hand, is a site of a circadian clock but the retinal clock appears to drive rhythms within the eye itself and it does not influence the rest of the circadian system.
i-3e99701b548d5e1cc2eb7f65a6f77267-a7 Primate Brain.jpg
[Image - Primate brain]
Apparently, all cells in mammalian body contain circadian clocks. These cells, in contrast to cells of the SCN, are called peripheral clocks or oscillators. Peripheral circadian oscillators cannot maintain rhythmicity in the absence of the SCN. When placed in a dish, peripheral clocks may undergo a few oscillations before becoming arrhythmic. In contrast, SCN cells cycle indefinitely in vitro. In addition, peripheral oscillators are not directly light sensitive, so the only way they can be entrained is via neural or hormonal signal driven by the pacemaker in the SCN. A number of humoral signals have been hypothesized to play this role, including cortisol and melatonin. The dynamics of entrainment of peripheral clocks appears to vary between the tissues, e.g., liver cells being much slower to reset to a new light-dark schedule than cells in some other organs. This observation can potentially explain jet-lag as a result of internal desynchronization between various peripheral oscillators.
Sex differences have been noted in mammalian circadian systems and a number of studies have shown an interaction between the circadian and the reproductive systems. The role of circadian rhythms in the measurement of daylength as an environmental signal for seasonal reproduction has been demonstrated quite decisively in mammals. An involvement of the circadian system in the timing of ovulation (primarily in rodents) is not as clear, although some persuasive data have been published. Effects of implants of steroid hormones have been seen in female rodents, both castrated and intact, with slight increases in period effected by estradiol. This effect is blocked by simultaneous application of progesterone and is also seen in embryonically feminized males.
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There are a variety of optical instruments that use light, lenses, & mirrors to help us see things. Compare the devices below and explain how they use light to enhance vision.
Glasses & Contact Lenses
Eye See You
Use the sites below to learn how we see. Create a diagram or re-enactment that shows how our eyes see.
Mirrors, Lenses, & Your Eyes
Anatomy of the Eye
Use the sites below to compare refraction & diffraction. Draw or write an everyday example of what each looks like. & explain how they differ.
Refraction & Diffraction
Reflection, Refraction, & Diffraction
Use the sites below to compare & contrast concave & convex mirrors. Which would you prefer to view yourself with? Use evidence from the sites to explain why.
The Science of Light
Concave & Convex Lens
Convex & Concave
A palindrome is anumber that reads the same backwards as it does forwards. The number 2332 is an example of a palindrome. Read either way the number is the same.
To Make A palindrome, add any number to its reverse. If it is not yet a palindrome, reverse the didgets and add it to the answer. Continue reversing and adding until the answer becomes a palindrome.
The example on this card, 57, is a two-step palindrome because it is reversed and added two times to become a palindrome. 57
+ 231
Work as a group to find all the numbers between 10-50 that can make a palindrome in two steps.
blogged by.... Jaira, Kenya, and Thea!
Mr. Logie visited us on Thursday to share his experience of becoming deaf and then how cochlear implants assisted his hearing. What is one thing that you learned from Mr. Loagie? Use specific details from his presentation to support your thinking.
My friends and I planned a technology conference for teachers. Between 80 & 85 teachers attended. We bought a t-shirt for each attendee that cost $8 or $9. How much did we spend on t-shirts? Explain your answer.
Today is 'Poem In Your Pocket' day. If you carried in a poem in your pocket, which would you carry? Why would you keep that poem in your pocket?
Some people ordered a pizza with 20 slices. Each person ate the same amount of slices. How many people ordered the pizza and how many slices did each person eat?
I was at the store when I saw they had headphones on sale for $2. Of course I had to scoop them up into my shopping cart! How many headphones do you think I bought and how much did I probably spend?
• post one possible solution
• name the strategy you used
• explain how the strategy helped you solve it
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A temporary gap, pause, break, or absence can be called a hiatus. When your favorite TV show is on hiatus, that means there are no new episodes — not forever, just for a little while.
Even things that go on for a long time take a break once in a while: one kind of break is a hiatus. If someone has to leave her job for a time, she's going on hiatus. A touring band will need to take a hiatus if the lead singer gets in an accident. The key thing about a hiatus is that it's an interruption of something that was happening, but it's not a permanent break.
Definitions of hiatus
n an interruption in the intensity or amount of something
abatement, reprieve, respite, suspension
abatement of a fever as indicated by a reduction in body temperature
remission, remittal, subsidence
an abatement in intensity or degree (as in the manifestations of a disease)
Type of:
break, interruption
some abrupt occurrence that interrupts an ongoing activity
n a missing piece (as a gap in a manuscript)
Type of:
an artistic or literary composition
n a natural opening or perforation through a bone or a membranous structure
Monro's foramen, foramen of Monro, interventricular foramen
the small opening (on both the right and left sides) that connects the third ventricle in the diencephalon with the lateral ventricle in the cerebral hemisphere
foramen magnum
Type of:
gap, opening
an open or empty space in or between things
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"url": "http://www.vocabulary.com/dictionary/hiatus"
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Skip to navigation | Skip to content
Snail's trail reveal ancient human migration
Banded wood snail (Cepaea nemoralis)
The snails share genetic markers that are extremely rare elsewhere in Europe (Source: Lauren Holden/)
Irish mystery solved? DNA analysis of snails may help unravel a mystery known as the 'Irish question' - why some wildlife species are found in Ireland and Europe, but not in Britain.
The snails (Cepaea nemoralis) from both Ireland and the Eastern Pyrenees region along the Spainsh-French border have large, white-lipped shells share genetic markers that are extremely rare elsewhere in Europe.
Along with other evidence, the findings also offer a new window into ancient human migrations.
"It's interesting to use snail genetics to find out how snails colonise, and it also maybe gives us a little insight into what humans were doing, too," says Angus Davison, an evolutionary geneticist at the University of Nottingham in the United Kingdom.
"One really neat thing about this study is that, if we accept that humans transported snails, it really gives us a unique insight into an individual journey 8000 years ago, and it gives us evidence of that from a source you might not imagine."
Research into this so-called 'Irish question' has failed to produce a single theory that explains how and when various species covered hundreds of miles from one place to the other.
To see if they could add any new understanding, Davison and colleague Adele Grindon focused on a distinctive-looking snail that had the same one-inch long shells in both locations. According to fossil evidence, the snails first showed up in Ireland about 8000 years ago. The molluscs had lived in southern Europe for tens of thousands of years before that.
The genetic material they analysed was essentially identical between the two regional groups, the researchers report in the journal PLOS ONE. The team was also surprised to find that they could trace the Irish population of snails directly back to a population in a specific region of the Pyrenees. The species lives nowhere in between.
Carried across by humans
The findings argue against a gradual move from one place to another, says Davison, and instead suggest that the snails migrated from Spain to Ireland in one step. He thinks it unlikely that birds transported the molluscs, partly because there are no known birds that migrate along that route that would have been large enough to carry the snails.
In the early 2000s, some studies proposed a connection between Ireland and the Pyrenees, but those studies were later shown to be too small and flawed to be convincing, says Allan McDevitt, a geneticist at University College Dublin, who specialises on questions about the colonisation of Ireland. The new research is far more robust.
"I think this study is important in that it does conclusively show that there is some link with Spain based on this snail," says McDevitt. "It's the most definitive proof yet that this is actually a very real migration that was happening."
"Ireland has always been a very controversial topic, both in how people reached it there and how animals reached it there," says McDevitt. "We're finding a lot of things by looking at small animals. They actually do tell us a lot about how humans were moving."
Tags: animals, genetics
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DOI: http://dx.doi.org/10.7554/eLife.03663.001
eLife digest
A region of the brain known as the cerebellum plays a key role in learning how to anticipate an event. For example, if you know that a puff of air is going to be directed at your eye, it's a good idea to close it in advance. However, how much you need to close it depends on how strong that puff of air is. A very strong puff might require closing the eye completely to protect it. In contrast, it is probably better to only partially close the eye if you know a lighter puff of air is coming, so that you can still see.
Extensive research has focused on how neurons in and around the cerebellum work together to achieve this goal. When an event—such as a puff of air—occurs, signals are sent to large neurons in the cerebellum, called Purkinje cells, by ‘climbing fibers’. However, climbing fibers were thought to be able to respond in only two ways: either they fire in a single burst to signal that an event has occurred, or they don't fire. It was therefore unclear how the finer details of the event (for example, the strength of the puff of air) are transmitted to the cerebellum.
Najafi et al. imaged the level of calcium in the cerebellum of mice, as this indicates how active the neurons are. When a puff of air was directed at the eyes of the mice, Najafi et al. saw that the size of the response of the Purkinje cells corresponded with how big the puff of air was. Najafi et al. show that the size of this response, which is based mostly on input from the climbing fibers, is also influenced by input from an additional unknown source.
These findings show that Purkinje cells of the cerebellum receive detailed information about the nature of an event, such as a puff of air. What remains to be seen is whether the cerebellum uses this information to learn the correct response, that is how hard to blink to avoid the expected puff.
DOI: http://dx.doi.org/10.7554/eLife.03663.002
Main text
The climbing fiber (CF) input to Purkinje cells (PCs) plays a key role in theories of cerebellar learning (Houk et al., 1996; Ito, 2000) by providing a teaching signal that sounds the alarm when an unexpected sensory event is encountered (Simpson et al., 1996; De Zeeuw et al., 1998; Ito, 2013). Support for this hypothesis comes from studies of Pavlovian eyeblink conditioning (Medina et al., 2000), a simple associative task in which subjects learn to blink to an initially neutral cue if it is repeatedly paired with a blink-eliciting instructive stimulus, such as a periocular airpuff. Previous work has shown that some CFs fire a burst of spikes when the unexpected periocular airpuff is delivered (Sears and Steinmetz, 1991; Nicholson and Freeman, 2003), and that this signal is sufficient for conditioning (Mauk et al., 1986; Thompson et al., 1998). All of these studies indicate that CFs are an important source of instructive signals to the cerebellum. However, we do not understand how CF signals encode even the most basic stimulus features such as the strength of the periocular airpuff, which has a major impact on the magnitude and the rate of learning (Spence, 1953; Smith, 1968).
CFs have peculiar physiological properties that have inspired a number of hypotheses about the underlying neural code (De Zeeuw et al., 2011; Najafi and Medina, 2013). CFs fire bursts spontaneously at ∼1 Hz (Thach, 1968), a low rate that is barely modulated during sensory stimulation (Simpson et al., 1996). Indeed, CFs are often described as binary because they respond by either not firing at all or firing a single burst regardless of how strongly they are stimulated (Crill, 1970; Gibson et al., 2004). Another peculiarity is that in the adult cerebellum, each PC is innervated by only one CF (Simpson et al., 1996). The CF-PC synapse is one of the most powerful and reliable in the brain (Schmolesky et al., 2002; Ohtsuki et al., 2009): each time the CF fires a burst, it evokes in PCs both a burst of sodium spikes in the soma known as a complex spike (Eccles et al., 1966; Thach, 1968), and a massive calcium-based spike in the dendrite (Llinás and Sugimori, 1980).
Based on these observations, it has been suggested that analog information may be encoded probabilistically, in the total number of bursts generated by an individual CF across many repeated presentations of the same stimulus (Fujita, 1982; Kenyon et al., 1998). Others have pointed out that sensory events synchronize CFs (Llinás and Sasaki, 1989; Lou and Bloedel, 1992; Wylie et al., 1995; Ozden et al., 2009; Schultz et al., 2009; Wise et al., 2010), which raises the possibility that stimulus information may be available in the precise timing of CF inputs (Schweighofer et al., 2004; Van Der Giessen et al., 2008), or in the level of co-activation in the CF population (Ghosh et al., 2011; Tokuda et al., 2013). Recent findings suggest an additional possibility: analog information, like the strength of an instructive stimulus, might be encoded post-synaptically by modulating the size of the PC response to individual sensory-driven CF bursts (Maruta et al., 2007; Najafi et al., 2014; Yang and Lisberger, 2014).
We have imaged PC dendrites of awake mice to investigate how CF-triggered calcium events encode information about the strength of a periocular airpuff stimulus. Because each PC receives input from a single CF (Simpson et al., 1996), we were able to discriminate the post-synaptic calcium events corresponding to individual pre-synaptic CF bursts and analyze their amplitude, timing and probability. Two-photon imaging also allowed us to analyze ensembles of PC dendrites whose CF inputs were co-activated by the periocular airpuff. Thus our experiments provide a unique opportunity to evaluate a variety of calcium-based codes in PCs, both at the individual dendrite and population levels.
We used a two-photon microscope to image calcium signals triggered by sensory-driven activation of climbing fiber (CF) inputs to Purkinje cell (PC) dendrites of awake mice. Mice were head-fixed on top of a freely rotating cylindrical treadmill and allowed to locomote in place while we delivered airpuffs of varying pressures and durations to the periocular area. In some experiments we used airpuffs of four different durations (12 experiments, 4 mice, 97 dendrites; durations: 8, 15, 30, 45 ms; pressure: 30 psi); in other experiments we used airpuffs of two different pressures (6 experiments, 3 mice, 39 dendrites; pressures 10, 50 psi; duration: 30 ms). We will refer to these two datasets as duration and pressure data, respectively.
CF-triggered calcium events in PC dendrites
As in previous reports (Sullivan et al., 2005; Ozden et al., 2008), PC dendrites in our experiments appeared as parasagittally aligned, tube-like structures (Figure 1A), in which large calcium transients (Figure 1B, circles) occurred spontaneously and in response to periocular airpuff stimuli (Figure 1B, triangles). We have previously shown that these calcium transients are triggered in each individual PC dendrite by activation of its one-and-only climbing fiber (CF) input, which also evokes a complex spike in the PC somata (Ozden et al., 2008). Hereafter, we will use the term ‘calcium event’ to refer to these CF-triggered calcium transients.
Figure 1.
Download figureOpen in new tabFigure 1. Imaging climbing fiber-triggered calcium transients in Purkinje cell dendrites.
(A) Field of view of an example experiment including 15 dendrites. (B) Example fluorescence traces of some of the dendrites in (A). Triangles indicate periocular airpuff stimuli of different strengths. Circles mark CF-triggered calcium events. (C) Box plot showing frequency of spontaneous calcium events across all dendrites. (D) Mean ΔF/F trace of spontaneous calcium events for all dendrites (gray lines; mean: black). (E) Pearson correlation coefficient of calcium events in pairs of dendrites as a function of the mediolateral separation (black: real data; gray: shuffled-frame control data).
DOI: http://dx.doi.org/10.7554/eLife.03663.003
A number of features confirmed the CF origin of the calcium events in our experiments. First, they occurred spontaneously at about 1 Hz (0.4–1.4 Hz; median 0.7 Hz; Figure 1C), which is similar to the characteristic spontaneous firing rate of CFs reported previously in awake animals (Thach, 1968). Second, they had a fast rise (∼10 ms Figure 1D), as observed for CF-triggered signals in other calcium imaging studies (Miyakawa et al., 1992; Eilers et al., 1995; Schmidt et al., 2003), and a slower decay t1/2 of 74 ± 13 ms (mean ± SD), which is in the midrange of previously observed kinetics using synthetic indicators (decay t1/2 = 25–170 ms; [Sullivan et al., 2005; Sarkisov and Wang, 2008; Ozden et al., 2009; Kitamura and Häusser, 2011]). Third, the probability of observing two spontaneous calcium events at the same time was highest for adjacent PC dendrites, and decreased rapidly as the mediolateral distance between dendrites increased (Figure 1E, black). This finding is consistent with previous studies demonstrating the prevalence of synchronous CF input to neighboring PCs in the same parasagittal microzone (Bell and Kawasaki, 1972; Sasaki et al., 1989; Ozden et al., 2009; Schultz et al., 2009).
Location of imaging sites
We imaged 101 sites on the surface of cerebellar cortex in 22 mice, including paravermal locations in lobules V, VI, and more lateral locations in simplex (Figure 2A,B). We were less frequently able to image the most medial parts of simplex due to the high density of blood vessels in that area. Consistent with the location of trigeminal CFs reported in previous studies (Miles and Wiesendanger, 1975a, 1975b; Manni and Petrosini, 2004), we found that many dendrites in the paravermal regions of lobules V and VI responded to periocular airpuff stimulation with a CF-triggered calcium event (Figure 2C,D). In contrast, dendrites on the surface of lobule simplex were mostly unresponsive, which is expected given the deep location of periocularly-related CF zones in this lobule (Hesslow, 1994; Mostofi et al., 2010; Heiney et al., 2014).
Figure 2.
Download figureOpen in new tabFigure 2. Location of imaged spots.
(A) Dorsal view of an exposed cerebellum showing all imaged spots (colored dots). Colors indicate the fraction of periocular-responsive dendrites in each spot. (B) Spots examined for response laterality are shown. Colors indicate the fraction of ipsi-specific dendrites in each spot. IC: Inferior Colliculus. IV–V, VI, VII, Simplex, and CrusI/II: cerebellar lobules. pf: primary fissure. Dashed line: midline. (C) Top: example ΔF/F traces from an ipsi-specific spot in response to ipsilateral (black, left) and contralateral (gray, right) airpuff stimuli. Bottom: each row shows PSTH of a dendrite in the example ipsi-specific spot in response to ipsi- and contra-lateral stimuli (left, right, respectively). (D) Same as (C), but an example bilateral spot is shown.
DOI: http://dx.doi.org/10.7554/eLife.03663.004
As observed in electrophysiological work (Hesslow, 1994; Mostofi et al., 2010), we found two types of periocular PC dendrites that could be classified according to the receptive field properties of their CF inputs: some dendrites responded with a CF-triggered calcium event only after ipsilateral periocular airpuffs (Figure 2B,C), while others had bilateral CF receptive fields and responded after ipsi- and contralateral periocular airpuffs (Figure 2B,D). In all the analyses presented below, we only evaluated the data for ipsilateral airpuffs. Our results were the same for both types of dendrites.
CF probability
Previous studies indicate that the likelihood of eliciting a response in an individual CF is proportional to stimulus intensity (Eccles et al., 1972b; Bosman et al., 2010). Thus, we first examined if individual CFs encode information about the strength of the periocular airpuff probabilistically, across repeated presentations of the stimulus. The raster plots of all the PC dendrites in our entire duration dataset demonstrate that CF-triggered calcium events occurred more reliably as the duration of the airpuff was increased (Figure 3A bottom; top: average). On average across all the PC dendrites, we found that the probability of calcium events increased gradually with increasing airpuff duration (Figure 3B, left; two-way ANOVA: F[496] = 238.5, p < 0.0001; Tukey's HSD, p < 0.01 for all pairwise comparisons), and pressure (Figure 3B, right; two-way ANOVA: F[238] = 58.93, p < 0.0001; Tukey's HSD, p < 0.001 for all pairwise comparisons).
Figure 3.
Download figureOpen in new tabFigure 3. Calcium-event probability encodes stimulus strength.
(A) Bottom: raster plots represent all trials of the duration dataset. Dots indicate calcium events. White and gray shades mark different experiments. For each experiment, all the trials corresponding to an individual dendrite are arranged consecutively. Number of dendrites imaged in each experiment is indicated on the left. Top: PSTHs, corresponding to the raster plots, indicate calcium event frequency at each time point. (B) Calcium-event probability for the spontaneous (sp) and airpuff-evoked conditions (d1–d4, p1–p2) (black: individual dendrites; red: mean ± SEM; left: duration data; right: pressure data). (C) Top to bottom: five dendrite categories based on how calcium-event probability varies with airpuff duration. For each category, calcium-event probability of individual dendrites (left: gray lines; right: rows of heatmaps) and their average (left, black lines) is shown. Triangles (left): The threshold of airpuff duration for evoking calcium events. Colors (right): calcium-event probability. d1–d4: different airpuff durations. p1–p2: different airpuff pressures.
DOI: http://dx.doi.org/10.7554/eLife.03663.005
The graded increase of calcium event probability with airpuff duration, which is shown averaged across all dendrites in Figure 3B, was evident in 58% of the individual dendrites (Figure 3C, top row), in which the probability and the stimulus duration increased with the same rank order. The remaining 42% of the dendrites were relatively unresponsive to all airpuffs below a certain threshold (Figure 3C, arrowheads), and responded with similar probability for all durations higher than the threshold (Figure 3C, rows 2–5). These latter CFs may encode duration information about stimulus strength in a binary manner, by providing a signal that tells the post-synaptic PC if the periocular airpuff lasted longer than a certain threshold. In summary, the response probability of individual CFs showed monotonic (i.e., non-decreasing) dependence on stimulus duration, with a dependency that ranged from graded to threshold-like.
CF latency
In agreement with previous electrophysiological reports of sensory-driven CFs (Ekerot et al., 1987; Kobayashi et al., 1998), we found that calcium events were evoked in PC dendrites at a wide range of latencies relative to the onset of the airpuff stimulus (onset latency: ∼25–150 ms; Figure 4A,D). Increasing the duration of the periocular airpuff resulted in progressively more long-latency calcium events (Figure 4A–C left; 67.1 ± 1.5, 71.8 ± 1.8, 78.8 ± 1.4, and 80.9 ± 1.4 ms for d1–d4 respectively; two-way ANOVA: F[393] = 11.85, p < 0.0001; Tukey's HSD: p < 0.05 except for d1–d2 comparison and d3–d4 comparison). The temporal jitter, as quantified by median absolute deviation from median latency (Figure 4C, right), was also reduced (23.3 ± 1.2, 21.1 ± 1.0, 19.3 ± 0.7, and 18.0 ± 0.8 ms for d1–d4 respectively; two-way ANOVA: F[393] = 5.42, p < 0.01; Tukey's HSD: p < 0.05 for d1–d3, d1–d4, d2–d4 comparisons). The analysis shown in Figure 4B confirmed that long-duration airpuffs evoked significantly more calcium events than short-duration airpuffs in the interval 75–150 ms after the periocular stimulation (Figure 4B; Kolmogorov–Smirnov test, p < 0.0001) but not in the interval 0–75 ms (Figure 4B; Kolmogorov–Smirnov test, p = 0.8). In summary, responses to airpuffs of increased duration are characterized by a higher likelihood of calcium events as the stimulus continues over time.
Figure 4.
Download figureOpen in new tabFigure 4. Calcium-event latency is modulated by stimulus strength.
(A) Onset-latency distributions of calcium events for duration data. (B) Each panel corresponds to a particular latency interval (indicated in the title) and compares for each dendrite (dots) the number of events evoked by two different durations of airpuff (y-axis: longer duration; x-axis: shorter duration; blue dot: mean; dashed: unity line). (C) Median onset latency (left) and variability (median of absolute deviation from median) of onset latency (right). Circles: average across dendrites; Error bars: SEM. (DF) Same as (AC), but for pressure data.
DOI: http://dx.doi.org/10.7554/eLife.03663.006
To test whether CF timing can provide a code for stimulus strength under conditions of constant stimulus duration, we varied the pressure of the airpuff. This led to a modest reduction in onset latency (81.3 ± 2.4 vs 79.6 ± 3.4 ms for p1 and p2 respectively) that was not significant (Figure 4D–F left; two-way ANOVA: F[134] = 0.98, p = 0.3), and did not alter temporal jitter (Figure 4F right; two-way ANOVA: F[134] = 0.13, p = 0.7). Higher-pressure airpuffs evoked more calcium events throughout the analysis window, both in the 0–75 ms interval (Figure 4E; Kolmogorov–Smirnov test, p < 0.01), and in the 75–150 ms interval (Figure 4E; Kolmogorov–Smirnov test, p < 0.001). These findings indicate that the onset latency of an individual CF input cannot be used to encode the pressure of the airpuff. However, additional information about stimulus strength may be available in the timing of the CF population (population co-activation). This question is addressed next.
CF co-activation
Previous work has demonstrated that groups of CFs converging on the same zone of cerebellar cortex become synchronized in response to sensory stimulation (Lou and Bloedel, 1992; Ozden et al., 2009; Schultz et al., 2009; Wise et al., 2010; Ghosh et al., 2011). We examined if the level of co-activation in the CF population provides information about the strength of the periocular airpuff stimulus. In 16 experiments in which we were able to image at least six PC dendrites simultaneously (Figure 5), we found that the number of synchronized calcium events in a 150 ms window after stimulus onset increased in response to airpuffs of longer durations (Figure 5A,B, top: two-way ANOVA, F[4394] = 199.75, p < 0.0001; Tukey's HSD, p < 0.05 for all pairwise comparisons), and higher pressures (Figure 5B, bottom: two-way ANOVA, F[2209] = 106.56, p < 0.0001; Tukey's HSD, p < 0.0001 for all pairwise comparisons).
Figure 5.
Download figureOpen in new tabFigure 5. Population coding of stimulus strength.
(A) Bottom: % coactive dendrites at different time points for all trials of the duration data. Colors indicate % coactivation. Top: PSTHs correspond to heatmaps at the bottom and show the average coactivation across all trials at each time point surrounding the stimulus. (B) Cumulative distribution of % coactive dendrites across all trials for the spontaneous (sp) and airpuff-evoked conditions (top: duration data; bottom: pressure data). (C) Measured and independent joint probabilities are shown for each dendrite pair (gray; dashed: unity line) for different airpuff durations. (D) % extra synchrony (measured minus independent joint probability) averaged across all dendrite pairs (error bars: SEM; sp: spontaneous; d1–d4: different airpuff durations. p1–p2: different airpuff pressures).
DOI: http://dx.doi.org/10.7554/eLife.03663.007
Since stronger airpuffs increase the probability of calcium events in individual PC dendrites (Figure 3), it is possible that the gradual increase in the number of synchronized calcium events (Figure 5A,B) simply reflects an increase in probability in a group of otherwise independent dendrites. To assess this possibility, we measured the joint probability for every pair of dendrites in each one of our experiments, that is the probability of observing a CF-triggered calcium event in both dendrites within the same 150 ms time window, and compared it to the joint probability expected for independent dendrites (Pij = Pi × Pj, where Pi and Pj represent the calcium-event probability of dendrites i and j in that same time window). We found that joint probability deviated significantly from the independence assumption for all airpuff strengths (Figure 5C; two sample t test, p < 0.001). We call this deviation ‘extra synchrony’ because it represents the synchrony beyond that expected solely from the calcium-event probability of two independent dendrites. Figure 5D shows that there was a gradual boost in the amount of extra synchrony as the airpuff duration or pressure was increased (Duration data: two-way ANOVA: F[4361] = 113.49, p < 0.0001; Tukey's HSD: p < 0.0001, except for d3–d4 comparison. Pressure data: two-way ANOVA: F[2136] = 10.27, p < 0.0001; Tukey's HSD: p < 0.05, except for p1–p2 comparison). In other words, the degree to which CFs are dependent on each other scales up smoothly with their overall response probability. These results suggest that CF co-activation may be controlled upstream, perhaps in the inferior olive, in a way that provides information about stimulus strength at the level of the PC population.
Size of CF-triggered calcium events
We have recently shown that the amplitude of CF-triggered calcium events is enhanced during sensory stimulation (Najafi et al., 2014). Here, we examined if the magnitude of this sensory-driven enhancement is graded according to periocular airpuff strength. Compared to the average fluorescence traces for spontaneous calcium events (Figure 6A, ‘sp’), the average fluorescence traces for sensory-driven calcium events revealed a gradual enhancement as the duration or the pressure of the airpuff was increased (Figure 6A top; only duration data is displayed). Note that the fluorescence trace of each individual dendrite was normalized to the peak value of its mean spontaneous calcium event (‘Materials and methods’). However, calcium events occurred with variable latency after the periocular airpuff, and for this reason the peaks of the average fluorescence traces in Figure 6A are substantially lower than ‘1’ (for comparison purposes, the ‘sp’ trace is plotted with the same temporal jitter as the d1–d4 traces).
Figure 6.
Download figureOpen in new tabFigure 6. Stimulus strength is represented in the size of calcium events and size of non-CF signals.
(A) Top: mean ΔF/F trace of calcium events across all dendrites for the spontaneous (‘sp’, green) and airpuff-evoked conditions (d1–d4: different airpuff durations; shades: SEM). Bottom: mean size of calcium events (‘ΔF/F-integral’) shown for each dendrite (black dots). Left: duration data: Right: pressure data. ΔF/F-integral values are normalized to the mean size of spontaneous events (dashed line). Red: mean ± SEM. (B) Same as (A), but for the non-CF signal. (C) Each panel corresponds to a duration of airpuff, and compares ΔF/F traces of calcium-event enhancement (i.e., evoked minus spontaneous event; black) and non-CF signal (green) in response to that particular airpuff duration (lines: mean across dendrites; shades: SEM). (D) Mean size of calcium-event enhancement is compared with mean size of non-CF signal for different airpuff durations (d1–d4; circles: average across dendrites; bars: SEM; dashed: unity line; ΔF/F-integral values are normalized to the mean size of spontaneous events. Arrowhead marks the longest duration airpuff, for which supralinearity is evident).
DOI: http://dx.doi.org/10.7554/eLife.03663.008
To quantify the gradual enhancement in Figure 6A (top), we measured the size of each individual calcium event by computing the integral of its fluorescence trace over a 100 ms time window after the peak (‘ΔF/F-integral’), and normalizing this value to the average ΔF/F-integral of all the spontaneous calcium events of the corresponding PC dendrite. Note that we only examined the fluorescence traces of individual calcium events and excluded trials in which the periocular stimulation resulted in two or more calcium events separated from each other by less than 100 ms (this occurred in <2% of trials and did not affect our results). This analysis confirmed that periocular airpuffs of longer duration and higher pressure evoked progressively larger calcium events (Figure 6A, bottom; Duration data: two-way ANOVA: F[496] = 80.74, p < 0.0001; Tukey's HSD: p < 0.05 except for d2–d3 comparison. Pressure data: two-way ANOVA: F[238] = 62.88, p < 0.0001; Tukey's HSD: p < 0.01 for all pairwise comparisons). Thus, the calcium elevation evoked in PC dendrite after activation of its CF input provides information about the strength of peripheral stimulation.
Contribution of non-CF signals
What neural mechanisms may contribute to the gradual enhancement of the fluorescence traces in Figure 6A? In addition to triggering calcium events in the PC dendrite, sensory stimulation also elicits a smaller calcium response that has a non-CF origin (‘non-CF signal’; [Najafi et al., 2014]). We found that the rise time (73 ± 8, 114 ± 7, 130 ± 7, 148 ± 7 ms for d1–d4 respectively; two-way ANOVA: F[375] = 12, p < 0.0001; Tukey's HSD: p < 0.05 except for d2–d3 comparison) and the size of this non-CF signal were graded (Figure 6B, top), with ΔF/F-integral becoming progressively larger as the stimulus duration or pressure was increased (Figure 6B bottom; Duration data: two-way ANOVA: F[496] = 122.61, p < 0.0001; Tukey's HSD: p < 0.0001, except for d3–d4 comparison. Pressure data: two-way ANOVA: F[238] = 71.85, p < 0.0001; Tukey's HSD: p < 0.0001 for all pairwise comparisons). These properties are consistent with the calcium responses driven by activation of parallel fiber inputs to PCs (Finch and Augustine, 1998; Takechi et al., 1998) which are known to increase progressively with stimulus duration (Gandolfi et al., 2014).
For the duration dataset, we had enough trials to make a direct comparison between the size of the non-CF signal and the size of the enhancement of the calcium event, which was obtained by taking the difference between the average fluorescence traces for spontaneous and stimulus-evoked calcium events. For short-duration airpuffs (Figure 6C, d1 and d2), the average non-CF signal resembled the average enhancement trace. However, for the longest-duration airpuffs (Figure 6C, d4), the non-CF signal was significantly smaller than the enhancement trace. These results are consistent with a model in which calcium events evoked by relatively weak sensory stimulation comprise a constant CF-triggered signal that adds linearly with a non-CF signal graded according to the strength of the stimulus (Figure 6D, d1, d2, d3). The supralinear response evoked by very strong airpuffs (Figure 6D, d4, arrowhead) could be explained if these stimuli were effective in triggering more spikes in each individual CF burst (Maruta et al., 2007).
Our results demonstrate that climbing fibers (CFs) represent information about the strength of a periocular airpuff in a number of ways, both at the individual-CF and population level. Consistent with previous reports of CF activity in awake animals (Gibson et al., 2004), we found no evidence for rate coding in our experiments: each presentation of the periocular airpuff resulted in either zero or one calcium event in the Purkinje cell (PC) dendrite, which would indicate that the pre-synaptic CF was activated at most once in virtually all trials (multiple activation in <2% of all trials). In the absence of a rate code, our results indicate that analog information about airpuff strength was encoded in: (1) the probability and latency distribution of individual CF inputs across repeated stimulus presentations, (2) the amplitude of the stimulus-evoked calcium event in individual PC dendrites, and (3) the level of co-activation of the CF population.
Below, we evaluate these different codes, and make a number of predictions about the underlying mechanisms and their potential role in regulating the efficacy of instructive signals during cerebellar learning.
Probabilistic coding in individual PCs
The response of a PC to sensory-driven activation of its CF input was originally described as an ‘all-or-nothing’ event (Eccles et al., 1966). Such a binary response cannot provide analog information about the graded features of an instructive stimulus in a single trial. However, current models of cerebellar function have pointed out that an individual PC could still extract analog information from its CF input by reading out a probabilistic code: by taking into account the reliability (Fujita, 1982; Kenyon et al., 1998), or the temporal precision (Schweighofer et al., 2004; Van Der Giessen et al., 2008; Tokuda et al., 2013), with which the all-or-nothing CF input is activated across many repeated presentations of the instructive stimulus.
We found that many individual PCs represent information about airpuff duration and pressure in a manner that is consistent with the probabilistic coding hypothesis. Higher-pressure (or longer-lasting) airpuffs evoked CF-triggered calcium events in PC dendrites in a larger fraction of trials than weaker (or shorter) airpuffs. This type of probabilistic coding may be particularly useful for regulating the efficacy of instructive signals during cerebellar tasks that are learned over many training trials. Every time the CF input fires, it triggers a wide range of synaptic changes in the cerebellar cortex (Schmolesky et al., 2002; Ohtsuki et al., 2009; Gao et al., 2012). Thus, the total amount of plasticity induced in the cerebellar cortex during training is likely to depend on the reliability with which CFs are activated by the repeated presentations of the instructive stimulus.
Our observation that the latency of CF-triggered events becomes progressively longer and less variable as a function of stimulus duration may also have implications for cerebellar learning. As is the case for neurons other brain regions (Dan and Poo, 2004), plasticity in PCs is strongly influenced by the relative timing of synaptic inputs. For example, parallel fiber (PF) synapses activated just before the CF input get weaker, whereas those activated just after the CF input get stronger (Piochon et al., 2012). Therefore, we predict that the total amount of plasticity induced in a PC over the course of multiple training trials will vary as a function of the number of times the instructive stimulus is able to activate the CF within the same small window of time.
Analog coding on single trials in individual PCs
We have shown that the amplitude of sensory-driven calcium events in a PC dendrite is graded and provides analog information about stimulus strength in single trials, that is more dendritic calcium if CF input fires in response to a strong periocular airpuff, less calcium for weak airpuffs. There are a number of non-mutually exclusive mechanisms that could contribute to this graded regulation of calcium events.
Our results provide considerable support for the possibility that the amplitude of calcium events in PC dendrites may be modulated by sensory-driven activation of a non-CF input. In support of this hypothesis we found that periocular stimulation activated CF and non-CF inputs converging on the same PC dendrite, and that activation of the non-CF input by itself was sufficient to cause a small dendritic calcium response that was graded according to stimulus strength. Although the source of the non-CF signal is unknown, we note that the excitatory parallel fiber (PF) input satisfies two conditions necessary to play such a role: (1) PF and CF inputs with similar receptive fields often converge on the same PC (Eccles et al., 1972a; Eccles, 1973), and (2) stimulation of PFs generates graded calcium responses in PC dendrites (Eilers et al., 1995; Gandolfi et al., 2014), that have similar kinetics to the non-CF signal (Finch and Augustine, 1998; Takechi et al., 1998; Wang et al., 2000) and can boost the amplitude of CF-triggered dendritic calcium events (Wang et al., 2000).
For the longest duration airpuffs, the amplitude of the non-CF signal was not large enough to fully account for the sensory-driven enhacement of the calcium events. This finding suggests that in addition to the non-CF signal, other mechanisms may also contribute to the modulation of calcium signals in PC dendrites during sensory stimulation. Recent studies have shown that the number of spikes in the presynaptic CF burst varies systematically depending on experimental conditions both in vitro (Mathy et al., 2009) and in vivo (Maruta et al., 2007; Bazzigaluppi et al., 2012), and that having just one extra spike in the CF burst can cause a substantial enhancement of the postsynaptic calcium response (Mathy et al., 2009). These observations raise the possibility that the graded modulation of calcium events in our experiments could be driven in part by small increases in the number of spikes of the CF burst (Najafi and Medina, 2013; Yang and Lisberger, 2014), especially for the longest stimulus durations.
The discovery of graded calcium signals in PC dendrites has important implications for theories of cerebellar learning. Dendritic calcium is responsible for triggering a variety of mechanisms of cellular plasticity that cause short- and long-term modifications in the strength of PC synapses (Gao et al., 2012). These plasticity mechanisms are tightly regulated and can be differentially engaged depending on the precise amplitude and duration of the calcium signal in the PC dendrite. For example, small differences in dendritic calcium can influence how much PF synapses will change in vitro (Coesmans et al., 2004; Tanaka et al., 2007), and can also determine the direction of learning-related changes in the firing of PCs recorded in vivo during eyeblink conditioning (Rasmussen et al., 2013). Thus, we predict that the amount and direction of plasticity induced in a PC during cerebellar learning will vary trial-by-trial depending on the dendritic calcium response triggered by each presentation of the instructive stimulus. This type of trial-by-trial regulation of CF-related instructive signals has been recently demonstrated in monkeys learning a cerebellar-dependent eye movement task (Yang and Lisberger, 2014).
Population coding in PC ensembles
Previous studies have reported that CFs converging on the same parasagittal strip of cerebellar cortex fire synchronously to signal the occurrence of an unexpected stimulus (Llinás and Sasaki, 1989; Lou and Bloedel, 1992; Ozden et al., 2009; Schultz et al., 2009; Wise et al., 2010). Our results confirm and extend these findings in two ways: First, we demonstrated that the level of synchronization is regulated by the strength of the stimulus, that is a larger fraction of the local CF population was activated after strong periocular airpuffs than after weak airpuffs. Second, we found that stimulus-related differences in the level of synchronization are partly driven by a mechanism that boosts synchrony beyond what is expected for independent CFs. We do not know the source of this extra synchrony or the mechanisms that modulate it during sensory stimulation. However, we note that electrical coupling of cells in the inferior olive (IO) plays an important role in synchronizing CF activity (De Zeeuw et al., 1997; Blenkinsop and Lang, 2006; Van Der Giessen et al., 2008), and that the coupling coefficient can be dynamically modulated up and down via stimulus-related activation of synaptic inputs to the IO (Llinás and Sasaki, 1989; Lang, 2002; Lefler et al., 2014; De Gruijl et al., 2014b).
Regulation of CF synchrony could be used to control the efficacy of plasticity signals (De Gruijl et al., 2012; Tokuda et al., 2013). For example, sensory events that activate many CFs simultaneously may be particularly effective for triggering NMDA-dependent plasticity in molecular layer interneurons of the cerebellar cortex (Duguid and Smart, 2004), via synchronized spillover of glutamate from multiple CF release sites (Szapiro and Barbour, 2007; Mathews et al., 2012). Another possibility is that CF synchrony could be used to set the strength of the plasticity signals sent by inhibitory PCs to downstream cells of the deep cerebellar nuclei (DCN; Otis et al., 2012), which are the final output of the cerebellum. This hypothesis is consistent with recent work showing that DCN cells exhibit rebound firing immediately after being released from the hyperpolarization caused by CF-driven synchronization of the PC population (Hoebeek et al., 2010; Bengtsson et al., 2011), and that this rebound can serve as a trigger for plasticity (Pugh and Raman, 2006). Release from hyperpolarization may also be sufficient to trigger calcium-based excitable events in dendrites of the DCN (Schneider et al., 2013), an effect that may be enhanced by direct monosynaptic excitation of DCN neurons by CF collaterals firing at the same time (Llinás and Muhlethaler, 1988).
In addition to playing a role in the modulation of plasticity signals in the cerebellum, sensory-driven regulation of CF synchrony could also have a more direct and immediate effect on motor control (Lang et al., 1999; Kitazawa and Wolpert, 2005; Llinás, 2011). Increased CF synchrony is observed at the onset of movement (Welsh et al., 1995; Ghosh et al., 2011; Ozden et al., 2012), and the level of synchrony has been shown to correlate with the timing and the velocity of spinocerebellar reflexes after sensory perturbations (De Gruijl et al., 2014a). In our experiments, a higher level of CF synchrony after a strong periocular airpuff might serve to enhance the reflex response by generating a faster or longer duration eyeblink movement (Evinger et al., 1991).
Conclusions and future directions
CFs are thought to play the role of teachers (Simpson et al., 1996; De Zeeuw et al., 1998; Ito, 2013), providing the instructive signals that trigger the mechanisms of plasticity necessary for cerebellar learning (Gao et al., 2012). To be useful, CFs must do more than alert about the occurrence of an unexpected event such as the presentation of a periocular airpuff in the early stages of eyeblink conditioning (Sears and Steinmetz, 1991; Nicholson and Freeman, 2003); they must also provide analog information to indicate how unexpected the event was, that is, how much stronger or weaker the airpuff was compared with expectations. Our experiments demonstrate that CFs and non-CF pathways together encode information about stimulus strength in PC dendrites when the presentation of the stimulus cannot be predicted. It will be important to understand whether and how the different calcium-based codes we have uncovered may be modulated during cerebellar learning, as the stimulus becomes predictable.
Materials and methods
Animal preparation
Experimental procedures were approved by the Princeton University Institutional Animal Care and Use Committee and performed in accordance with the animal welfare guidelines of the National Institutes of Health. The details of the animal preparation have been described previously (Najafi et al., 2014). Briefly, C57BL/6J mice (female, 8–14 weeks) were deeply anesthetized by inhalation of isoflurane (3–5% induction; 0.5–1.5% maintenance). A small area of the cerebellum was exposed (diameter: 3 mm), and a Kwik-Sil plug, pre-molded on a coverslip, was secured over the dura using a two-piece, stainless steel headplate. Throughout the surgery, sterile saline was used to keep the dura wet. Animals’ body temperature was monitored and maintained near 37°C. Analgesics (Meloxicam, 5 mg/kg, subcutaneous) were injected. At the end of the surgery, anesthesia was removed and mice were returned to their cage for recovery.
Imaging CF-triggered calcium events
Two-photon calcium imaging was performed the day after surgery. Mice were anesthetized with isoflurane (3–5% induction; 0.5–1.5% maintenance). Kwik-Sil plug was removed and calcium indicator (Oregon Green 488 BAPTA-1/AM, Invitrogen, Carlsbad, CA) was injected 150–200 µm below dura, by applying brief positive pressure through a glass pipette (Ozden et al., 2012). A new Kwik-Sil plug was used, anesthesia was removed, and the animal was transferred and mounted on a cylindrical treadmill integrated with the imaging apparatus. Calcium imaging was performed on awake animals using a custom-built two-photon laser scanning microscope (Sullivan et al., 2005). Fluorescence movies (32 × 128-pixel; 64 ms/frame) were recorded using ScanImage software (Pologruto et al., 2003). Animals were monitored throughout the experiment with a camera.
PC dendrites were identified from the imaging movies using independent component analysis (Ozden et al., 2012). The fluorescence trace (ΔF/F) of each dendrite was computed, frame-by-frame, as (F-Fb)/Fb, where F is the mean fluorescence intensity of the pixels contributing to a dendrite. Fb is the baseline defined as the lowest eighth percentile of the fluorescence values within a 1-s window. Calcium transients were identified as CF-evoked calcium events using a two-step process (Ozden et al., 2012): first, the kinetic properties of the ΔF/F signal had to match a template. Second, the peak amplitude of the transient had to be larger than a predefined threshold.
Periocular stimulation
A pressure injector system (Toohey Spritzer) connected to a 25 gage needle was used to deliver airpuffs to the animal's ipsilateral eye (inter-trial interval: 4 s; 35 trials per airpuff condition per experiment). Two different sets of experiments were performed. In one set, ‘duration’ experiments, the airpuff pressure was kept the same (30 psi) and four different durations of airpuffs were applied (8, 15, 30, 45 ms). In another set, ‘pressure’ experiments, the airpuff duration was constant (30 ms), and two different airpuff pressures (10, 50 psi) were applied.
Data analysis
The ΔF/F traces presented in all figures were normalized. Normalization was done for each dendrite separately, by dividing the ΔF/F trace of the dendrite by the peak value of its mean spontaneous calcium event. Calcium events with a peak in the interval 50–200 ms after the periocular stimulus were considered airpuff-evoked. The onset latency of calcium events (Figure 4) was computed manually by inspecting each airpuff-evoked calcium event. Coactivation (Figure 5) was computed for each trial separately by dividing the number of dendrites with an airpuff-evoked calcium event, by the total number of responsive dendrites in the field of view. The measured joint probability for a pair of dendrites (Figure 5C) was calculated as the fraction of trials in which both dendrites in the pair exhibited airpuff-evoked calcium events. The independent joint probability was computed by multiplying the calcium-event probability of the two dendrites (Pij = Pi × Pj). The d1–d4 traces in Figure 6A were computed by averaging the normalized ΔF/F signals of all the individual dendrites in trials with a calcium event. To provide a fair comparison, the ‘sp’ trace was computed the same way, after substituting the ΔF/F signal of all the stimulus-evoked calcium events in a given dendrite with the normalized ΔF/F signal corresponding to the average spontaneous calcium event for that dendrite. Thus, the temporal jitter in the onset latency of the individual calcium events comprising the ‘sp’ trace was the same as in the d1–d4 conditions. The size of individual calcium events (ΔF/F-integral, Figure 6) was computed by taking the integral of the normalized ΔF/F signal over the interval [t t + 100 ms], where t is the time point at which the peak of the event occurs. The non-CF signal (Figure 6B,C) was analyzed in trials without any calcium events within 50–200 ms of the airpuff stimulus. The size of the non-CF signal was measured in a similar way as the calcium events, by taking the integral of the normalized ΔF/F signal over the interval [t t + 100 ms], where t is a time point selected randomly within 50–200 ms of the stimulus. Error bars in figures indicate SEM. Values in text are mean ± SEM unless otherwise specified. Tests of significance were two-tailed.
We thank A Kloth for help with eyelid acquisition software, I Ozden and D Dombeck for help with imaging in awake mice, and C Arlt and C Wilms for comments on an early version of the manuscript. This work was supported by grants to JM (Searle Scholars Program, NIH R01 MH093727), AG (New Jersey Commission on Brain Injury Research CBIR12FE1031), and SS-HW (NIH R01 NS045193, WM Keck Distinguished Young Investigator, NIH RC1 NS068414).
Decision letter
Michael Häusser, Reviewing editor, University College London, United Kingdom
Thank you for sending your work entitled “Coding of stimulus strength via analog calcium signals in Purkinje cell dendrites of awake mice” for consideration at eLife. Your article has been favorably evaluated by Eve Marder (Senior editor), a member of the BRE, and 2 reviewers. The following individuals responsible for the peer review of your submission have agreed to reveal their identity: Michael Hausser (Reviewing editor); Tom Otis (peer reviewer).
The authors have used in vivo two-photon calcium imaging to perform a careful, parametric assessment the population activity in climbing fibers in response to a sensory stimulus (peri-ocular air puffs) of different strength and duration. Given the central role of climbing fibers in cerebellar physiology this is a significant topic of study. The authors are the first to quantify in awake mice how a population of climbing fibers represents a sensory stimulus known to drive learning. They find that these stimuli are represented at a population level in a modular fashion and uncover some tantalizing evidence that the individual climbing fiber inputs to single Purkinje neurons are graded. This latter finding is novel and complements some recent high profile work showing that graded signals represent a population-wide signal relevant to learning (Yang & Lisberger, 2014).
Overall, both reviewers found the work to be thorough and exciting: this is a very well-conducted study with a clear and important message that is of wide interest for a broad audience. Although some of the results could be considered predictable given prior work, the evidence is solid and persuasive. For example, the “extra synchrony” analysis (Figure 5) is particularly elegant and effective. The manuscript should be ready for publication in eLife once the following major issues are addressed (editors’ note: minor comments are not shown):
Major comments:
1) It would strengthen the paper if the authors could shed more mechanistic light on the analog calcium signal detailed in Figure 6. For example, it would be particularly compelling if the authors could provide some direct evidence that parallel fiber inputs are responsible for this effect. At the very least, they should provide some speculation about the mechanism.
2) It is very important for the authors to clarify exactly how the normalization procedures in Figure 6 have been conducted. For example, it is unclear how the signals in panel A, top are normalized. Relatedly, in panel B bottom, the dotted line no longer indicates the amplitude of spontaneous calcium events and for the sake of consistency.
3) Non-climbing fiber calcium transients: The authors show that the non-CF transients saturate: d4 does not evoke a larger response than d3 (Figure 6B). Yet, they claim that the supra-linear increase in response to d4 as compared to shorter duration stimuli might be expected for a parallel fiber-driven dendritic amplification mechanism. If indeed a parallel fiber-driven mechanism would be active, why is this not visible at d3 – when the non-CF response is identical to that of d4?
4) The authors discuss their work in the light of induction of various forms of plasticity in the cerebellar cortex. This is a wise choice and it is well documented why the learning context is indeed probably highly relevant. However, we cannot exclude the possibility that the current findings are also relevant for short-term effects on motor behavior, e.g. reactions following perturbations (see e.g. CS calcium imaging study of WT and Cx36-/- by De Gruijl et al., 2014 in J Neuroscience). The latter study in fact also shows the mechanisms through microzones (rather than zones). Please consider discussing this issue next to the long-term effects.
DOI: http://dx.doi.org/10.7554/eLife.03663.009
Author response
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Facundo: Or, Civilization and Barbarism
Facundo: Or, Civilization and Barbarism Summary and Analysis of Chapters 1-2
Summary of Chapter 1
The narrator, Sarmiento himself, begins with a description of the physical terrain of Argentina. It is a country that has suffered from the vast, empty expanses of desert and plains; its characteristic is immensity. Savages roam the land and traveling wagons must be wary of the hordes. Life outside towns is frightening and insecure. This has led to a “certain stoical resignation to death by violence, which is regarded as one of the inevitable probabilities of existence” (10).
There are three different sections of the country, each with its own characteristics. In the north is the forest, and in the center are the plains; their vastness is as a sea on land. Many navigable rivers are there. The people who live near these rivers are happy to have them as an impediment to the gaucho.
The rivers connect the cities, the most important being Montevideo and Buenos Ayres. The latter is the only city in contact with Europe, the only city with power and revenue, the city the provinces asked for assistance, and when receiving none, sent her Rosas. Barbarism is ever-present in Buenos Ayres now. The city favors monopoly but it is clear that the “progress of civilization must culminate in Buenos Ayres” (13).
The country was seemingly destined to become a unified republic since it did not have independent settlements like North America. Philosophers claim the mountains made strongholds for liberty and the plains for despotism. The plains give the interior an Asiatic character and the wilds of Asia come to mind. What results is brute force, the strong prevailing, and lack of justice and accountability. Those who live far from society have to struggle alone with nature.
There are two different races in the districts: the Spanish and the native. The Spanish are in the rural districts, the negro race (almost all gone but having left mulattos and zambos) mostly in cities, more progressive and civilized. The people of both races are idle, incapable of industry. The natives are dirty, ragged, and idle.
In the plains there are fourteen cities, each the capital of a province. Each province, except San Juan and Mendoza, fosters a pastoral lifestyle. Argentinian cities appear regular, civilized, and elegant. Buenos Ayres and Cordova have established subordinate towns as well. In the cities, people appear European, but outside they are “South American” in their dress and habits of life. These people are very different from each other; civilization seems contained in the cities.
Outside the cities lies the remaining population. Their lives are pastoral, reminiscent of the Asian plains. There are no nomads, though, because people remain solitary. There is indolence and barbarism, and “society has altogether disappeared” (21). It seems more like old Slavonic Sloboda or the feudal Middle Ages in its “isolated self-concentrated feudal family” (21).
It certainly does look like the lifestyle of Spartans and Romans but there is a difference: those ancient groups also used others to do their work and spent their time on other activities, but the Argentinians have no cities, municipalities, or any social development. There is no moral progress or intellectual development; the pastor and pulpit hold no charms. Religion is primitive; Christianity is corrupted.
Similarly, education is limited. When boys grow up to be men, they become indolent and independent. This is the public life of the gaucho – he is a man of brutishness, the product of the struggle with nature. This he claims as his reason for superiority; he believes himself prodigious and powerful. He looks down on the luxury-loving European and believes nothing is worse than a life of refinement. His physical powers are developed but he has no intellectual ones.
The life of the gaucho is one of barbarism and “the impossibility and uselessness of moral and intellectual education” (27).
Summary of Chapter 2
Some poetry exists in the state of things, especially between mind and matter, and civilization and barbarism. Someone like James Fennimore Cooper in North America understood this, and in Argentina the poet Echevarria did as well in his work “The Captive.” He wrote of the desert, immeasurable spaces, and wandering savages.
Certain conditions lead to peculiarities in character that are replicated in places with those same conditions. There are similarities between the pampas of Argentina, the frontiers of America, and the wilds of Asia.
When the inhabitant of Argentina looks beyond the horizon, he does not know what lies out there, except for perhaps “wilderness, danger, the savage, death!” (31). It is only natural that poetic feelings arise from this reality. Images remain “deeply engraved on the soul” (31).
When asked about lightning, gauchos rattle off myths, superstitions, and vulgar tradition. The gaucho’s poetry contrasts with the civilized work of poets of the city such as Echevarria and Dominguez.
Gaucho poetry is irregular and less formal. It has an engrained interest in music as most people play instruments. The most popular measure for songs of the day or warlike odes is the Vidalita. The guitar is the most popular instrument.
There are a few types of occupation to describe. First, there is the Rastreador, or track-finder. Gauchos in the interior fill this role. They are “grave, circumspect” (35) and full of dignity that befits their grand possession of knowledge. They can follow any track and solve crimes if necessary. One such personage, Calibar, had been doing this for forty years and achieved great renown.
The Baqueano, or the path-finder, controls the fates of individuals and provinces. He is grave and reserved as well; he knows all the secrets of campaigns and knows the topography of the land. He announces the approach of enemies and the direction from whence they come. The most famous was General Rivera, who “knew every tree that grows anywhere in the Republic of Uruguay” (40).
The Gaucho Outlaw is a squatter and misanthrope. He knows everything about the wilderness, but has no moral compass. People dread him and the law covets him; there is an immense respect accorded him. He is rarely pursued since the horses would just be lost. His renown pervades the land. He is not a bandit or highwayman, and does not murder; instead, he steals horses.
The Cantor, or minstrel, sings about the heroes of the pampa. He records history, customs, and biography and thus does a service to the country. His abode is unfixed. Sometimes his stories of others include his own exploits. When composed in the instant, his work is irregular and clumsy, more suited to narrative rather than the expression of feeling.
There are other types of people but they are not as useful in conveying the customs of the country.
There are a couple of things to note immediately about this text after reading the first couple of chapters and before proceeding to the next. First, this is a strange hybrid work, one of history, biography, travel narrative, and fiction. Critics do not often agree on exactly what genre it belongs to. Ostensibly every figure and every fact is accurate, as Sarmiento claims, but there is most definitely embellishment and factual fungibility. Sarmiento’s goal was to expose the barbarism exemplified by Rosas by focusing on the only slightly less monstrous Facundo. He wanted to explain why his country was the way it was, why barbarism was spreading and resulting in disasters, and how civilization was under threat. The work, as Ilan Stavans writes, “was conceived as many books in one, and the end product is something of a hybrid.” Sarmiento wanted to “make history more palatable, more convincing” and knew he “needed to establish a marriage between historical information and imaginative, fabricated ingredients, between fact and fiction… impartiality, he trusted, was less important and made worse literature than partisanship.”
Second, the author is not merely a writer, but a renowned intellectual and statesman. This work is considered the beginning of Argentinian literature, and the name Sarmiento is universally known in Latin America. It is an absolutely seminal and foundational text.
In the first two chapters, Sarmiento sets out to explain the characteristics of his country and how it created a man like Facundo. He begins with large generalizations, comparing the city and countryside. The cities are places of civilization, of Spanish influence, of learning and progress. They are under threat from the barbarism of the provinces, which are desolate wastelands where the inhabitants have to fight tooth and nail against nature to survive. Sarmiento wants to convey how the natural environment shapes the character of people; these are inextricably linked. Men like Rosas and Facundo become barbarous in large part because of their savage, rough existence. They are gauchos, the most famous of the recognizable Argentinian types Sarmiento describes.
Significantly, Sarmiento never actually saw the pampas, the plains of Argentinian provinces. This is very similar to the North American author he references – James Fenimore Cooper. In her article comparing Facundo and Natty Bumppo, Cooper’s most famous character, Dorothy Sherman Vivian begins by accounting for the similarities in the authors’ Romantic inspirations and how they both “demonstrate the effects of nature on the physical habits and moral character of man.” Nature shapes their physical and moral character, and pushes them to assert their physical prowess. However, the similarities end here. Cooper “stresses the civilized aspects of his main character (clothing) while Sarmiento stresses the bestial aspects of Facundo”; nature has made these two men very differently.
Sarmiento sees nature as defeating man, not being tamed by him. He has a romantic perspective shaped by the fact that his country was not yet as far in its economic progress, while Cooper is comfortably on the other side, asserting that nature is mostly tamed by man. Sarmiento “treats nature as savage, brutal, and difficult to dominate” and believes that nature makes men like animals (in the next section Facundo will be compared to a tiger). Sarmiento is concerned that there is a loss of the “civilizing code.” Facundo is amoral, barbarous, and excessively individualistic. Natty Bumppo is also individualistic, but governed by an ethical code. Vivian concludes, “To Sarmiento, a lack of civilization and an excess of nature will lead to a loss of morality; to Cooper it is Nature that teaches and an excess of civilization that threatens.”
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What was Shakespeare's representation of women and how does he show this in the novel "The Merchant Of Venice"?
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What was Shakespeare's representation of women and how does he show this in the novel "The Merchant Of Venice"? In 'The Merchant Of Venice' Shakespeare portrays the character of Portia as a subservient woman but as the play progresses he develops the character and Portia becomes the most dominant character in the play, overcoming the stereotype that restrains women in the society at that time. Throughout the play Shakespeare develops Portia's character from what seems like a subservient woman, who is forced into a marriage, to an independent woman who is considered an equal by her husband. The arranged marriage shows that Portia was given no freedom by her dominant dead father, which may be why Portia seems to make horrible comments about all the suitors that come to try to complete the life - changing task. At the beginning of the play Portia has no control over her financial well-being or an unarranged marriage, she is a prize to be won - here the woman is trapped in a patriarchal society, "I may neither choose who I would nor refuse who I dislike; so is the will of a living daughter curb'd by the will of a dead father". (Act 1 scene 2 line 22 - 25) ...read more.
However I think that by the end of the play, a schoolgirl crush, which I can tell from the way Portia remembers Bassanio immediately (Act 1), has turned into love, which is why Portia forgives him. Portia frees herself from being a possession by inventing her own task (the ring task). When Bassanio fails this test, the effects only seem to strengthen their relationship and by the end of the play Portia freely gives herself to Bassanio and therefore has a lot more freedom. By the end of the play, Shakespeare has left Bassanio in a position where Portia has Bassanio begging at her feet, asking her not to divorce him (Act 5 scene 1 line 199 - 231). Shakespeare manages to create this situation by developing Portia's character to shows choice, authority and feminism by forming her own special task where she can show that her character is strong and assertive. She also dresses as a man to gain respect - Portia demonstrates independence, wit, skill and shows she is learned when she outsmarts all the men in the courtroom. This imaginative act works when Portia wins the case showing that the shackles of patriarchal society bind not all women. (Act 4) Portia's confidence and language changes slightly in the courtroom as well. ...read more.
Shakespeare used exactly the same method to free Jessica from the shackles of patriarchal society for example, when Jessica created the ring test. By the end of the play both the main female characters, Jessica and Portia had much more freedom and seemed much more opinionated than at the beginning when both were 'owned' by their father's who didn't appreciate their potential. My first impression of women in the time of Shakespeare and in the play was that they were of great importance, even after reading The Merchant Of Venice. The main reason I thought that women were held in great esteem was because the greatest Queen who ever ruled England (Queen Elizabeth) was at the throne at the time. Also because after reading The Merchant Of Venice for the first time I thought that Portia was admired and was free/ independent. But after studying the text more closely and looking for evidence of this conclusion I realised that most women were dependant on men and that strong female characters, such as Portia, were great role models but were the minority in the female population. Finally, I think women weren't given many opportunities and had to suffer under many constraints at that time e.g. that women were mainly controlled by their father's or 'the man of the house' - this was due to the stereotype that all women should stay at home and cook, clean and look after the children. By Amber Woodhams, 10 More ...read more.
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Related GCSE The Merchant of Venice essays
1. Is 'The Merchant of Venice' a racist play?
to kill his only daughter for the sake of a few ducats. He is furious and as a result of this theft, he greets the rumour that one of Antonio's ships has been wrecked with savage delight. He says, "to bait fish withal, if it will feed nothing else".
2. Jos&amp;eacute; Mart&amp;iacute;nez Ruiz,&quot;Azor&amp;iacute;n&quot;: La voluntad as a regenerational novel.
It is more a case of Mart�nez Ruiz becoming Azor�n than the other way around. La voluntad also has metafictional characteristics, as shall be seen in Niebla, within it there exists a theory of the novel, what it should be like, and a critique of the novel.
1. The Merchant of Venice is a Racist Play.
Austen obfuscated vvysqfvk's functionalism theory. On the surface this would show that there were more things he cared about than money and possessions. Alternatively, we could conclude that this meant the opposite. He needed possessions to retain his memories and that without the ring, his memories about the time with his wife, would be meaningless.
2. Shakespeare&amp;#146;s three women characters &amp;#150; Portia, Nerissa and Jessica &amp;#150; are portrayed as typical ...
if the devil be within, and that temptation without, I know he will choose it." And, "I could teach you how to choose right." The first of these tells us that she does know which casket has her picture in it also tells us that she wishes to discourage the suitor from choosing it.
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sense organ
a body part that has special nerve cells that gather information about the surroundings.
nerve cell
a cell that gathers and carries information in the body.
nerve endings
a tiny branch of a nerve cell that gathers information.
spinal cord
a thick bundle of nerves that connects the brain and nerves throughout the body.
the four taste buds are...
sweet, sour, bitter, and salty.
The sense of taste comes from tiny___________ on your tongue.
taste buds.
Taste buds have ________________ that gather information about the four taste buds.
Nerve cells.
you get _________ from your surroundings.
the clear covering that protects the front of your eye.Bends light.
Changes the size of the pupil to let the right amount of light in.(colored part of eye.)
allows light inside of the eye.
Bends light to focus light on the retina.
information is gathered about the light in the retina.A thin layer of nerve cells at the back of the eye.
optic nerve
a nerve that sends information to the brain.
White part of the eye.
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Look again at From War Music and Refugee Blues. What impressions of conflict does each writer create by the ways in which the events are presented?
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Look again at 'From War Music' and 'Refugee Blues'. What impressions of conflict does each writer create by the ways in which the events are presented? In your answer you should make close reference to the language of poems. Both poems deal with conflict but both in different ways. In 'War Music', we are shown physical conflict, at first creating a heroic image of Ajax. However, 'Refugee Blues' deals with inner conflict due to their German-Jewish background of which they are pre-judged against. Moreover, its structure of twelve stanzas is interesting with its relation to twelve bar blues: music with a depressing tone and the fact that each stanza could represent a month and therefore, in total, a year. This effectively emphasises the German-Jewish couple's stressful struggle in their attempted migration. Like 'Refugee Blues', the title 'From War Music' already suggests a relation to music. ...read more.
Moreover, it shows us their identity before they even mention they are 'German Jews' as this is a typical Jewish phrase. Their racial background is the main focus since it is the cause of all the inner conflict due to the rejection and depression which is created throughout. In 'War Music', the writer, Christopher Logue successfully paints us a picture of the action. The Trojans which 'swarmed so thick' are closely related to air which was also 'thick with arrows' suggesting that there was almost as many Trojans as arrows. The use of onomatopoeia gives us a realistic sense of sound with the use of words such as 'tickered' and 'clamouring', we are able to visualise such a chaotic but heroic image. Furthermore, the furious pace of the battle is reinforced with a metaphor of Ajax's head reaching 'back and forth//like a clapper inside a bell made out of sword blades'. ...read more.
The second stanza describes to us the one on one battle between the two of which Ajax's destiny is shown through Hector's quickness as he 'skipped', 'jived' and 'snicked the haft clean through its neck'. Again Logue skilfully uses the descriptions to create such a scene of conflict. Moreover, God is once again mentioned in conclusion as he 'stood by Hector's elbow' and not by Ajax's. Evidently, God's appearance is repeated, emphasising that Hector was destined to win and Ajax destined to lose. In conclusion, both poems are successful in conveying conflict but both in different ways. They each conclude negatively where in 'Refugee Blues', it ends in desolation 'in the falling snow'. The use of pathetic fallacy reinforces the tone of depression and pessimism. Furthermore, 'From War Music' ends with a strong statement that 'The ship was burned'. It stands out to us like the first stanza since it is only one line but it clearly links back to the beginning and middle. Overall, each poem uses the theme of conflict effectively and successfully, leading to the negative conclusions. ...read more.
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Related GCSE War Poetry essays
they will arrive, even that good chaperon "Immortality" may not deliver the clarity and comfort promised in Victorian accounts of Christian death or marriage? with God. Dickinson makes no overt claim that death is frightening or heaven? unreachable, but she effectively undercuts the apparent calm certainties of the first three stanzas through the understated "chill" of the final three.
2. A Comparison between Dulce et decorum est. by Wilfred Owens, and Refugee Blues by ...
Owen is explaining here how all his previous evidence of the 'children ardent for some desperate glory' - the war itself, are all pointless. He is trying to gain the readers support in his argument, and at this point it seems that the reader is imagined in the place of the person Owen might be telling this to.
1. A comparison of Philip Larkin's The Explosion and WH Auden's Funereal Blues.
The reader is not shocked by the poet's delivery of the news. We knew there would be an explosion from the title. The news is delivered without melodrama and even the cows are unmoved as they paused and only "stopped chewing for a second" (Line 14)
done; I'm glad it's over" this shows a true decay amongst human relationships because there is no longer that urge to be with someone because of love, or because you need to, it is just because it is a habit, something you have to deal with.
1. The changing tradition of war poetry
In the last stanza, the tone gets serious and it starts talking about your home. The rhyme I have noticed is an "AB" rhyme because it makes it easy to remember so the message is passed on. Also there is a rhyming scheme in the poem as well because every other line rhymes.
2. Poetry Essay on Funeral Blues &amp; The Triumph of Death
The theme for 'The Triumph of Death' is the opposite because William doesn't want people to worry about him when he has gone, but do the complete opposite and be happy he has gone to a better place which he prefers.
1. Show how the writer uses the form of poetry to protest against a situation ...
also quite a shock because it is such a new idea, that Death answers to the same forces as everything else and is not as powerful and therefore not as "dreadful" as we first thought. This reaction would not have been possible if Death had not been personified because how could you feel pity and sadness for an inanimate object?
It was after this match when he was drunk that he asked to join the army just to appear manly to the ladies as someone suggested he would look dashing in a uniform. He went as far as lying about his age and as a result he had joined the war.
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History of Chinese Water Deer
Chinese Water Deerare different to many deer species in that they have no antlers and have downward pointing tusks - this and other characteristics have led to Chinese Water Deer being assigned their own genus (Hydropotes). Water Deer are Native to China and Korea and are classified in two distinct subspecies: the Chinese Water Deer (Hydropotes inermis inermis) and the Korean Water Deer (Hydropotes inermis argyropus). The CWDF is mainly concerned with the former.
The population in China is considered to be 'Vulnerable' and in fact there may soon be more Chinese Water Deer in the UK than in their native China. The species was introduced to Woburn Park, Bedfordshire, England at the end of the nineteenth century. It bred well and was moved to other collections. Escapes and releases resulted in the current wild population, which occurs primarily in eastern England, but has the potential to spread over much of lowland southern Britain.
As a non-native species, following the principles of the Bern Convention, the UK Government is already considering risk management options to prevent further spread and deliberate introductions outside the current distributional range. So far its impacts on native biodiversity and agriculture have been negligible though Chine Water Deer are increasingly implicated in road traffic accidents.
As a conservation issue, the UK population of Chinese Water Deer is considered to be of exceptionally high value to the survival of a healthy global population
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Tomb Digging and Cutting Techniques
The construction of royal tombs was a relatively easier task in the New Kingdom than in previous eras when huge pyramids were being constructed. The chambers and corridors of New Kingdom rock-cut tombs were carved into limestone hills and cliffs. Work space and light sources were limited and working conditions were hot, humid, and dusty, but the quarrying of soft limestone was a fairly simple process. The location of the tomb was important, and finding an appropriate site was a task entrusted only to high officials of the court. Once an acceptable site had been decided upon, work crews began to cut into the rock, first creating an irregular working passage, then refining it into corridors and chambers. Because many tombs were never fully completed, we have examples of construction and decoration at several different stages of the process [16258, 16286, 14440]. 16258 16286 14440
An essential part of tomb cutting was the use of an axial line painted on the ceiling, creating a base line from which other measurements were made [16269, 16144]. This ensured that walls were parallel or at right angles to each other, doorways were properly aligned, and the tomb's axis was straight. Measurements were in cubits (52.3 cm/20.9 inches), subdivided into palms (seven per cubit, each 7.5 cm/3 inches long) and digits (four per palm, each 1.9 cm/0.76 inches long). 16269 16144
The initial rough cutting was likely done with percussive and cutting tools made of stone, most likely flint or chert, which can be found in abundance in the limestone deposits. Both stones are extremely hard and had been used for hundreds of thousands of years before the New Kingdom in Egypt. Final finishing of a wall was done with copper and bronze tools. Careful studies have been made of the chisel marks left on the walls of tombs in order to determine the sizes and shapes of the implements.
A wealth of written material in the form of hieratic dockets, graffiti, inventories, workforce lists, and reports have been found in the Valley of the Kings and Dayr al Madinah, the village of the workmen who were responsible for the construction and decoration of the royal tombs. We know that the workforce was divided into two crews each with its own overseer, the "Gang of the Left" and the "Gang of the Right," referring to the side of the tomb to which they were assigned. In addition to the quarrymen who did the basic hewing of the tomb, other workmen performed such tasks as smoothing the walls and ceilings and applying the gypsum plaster that covered the walls and ceilings [13313, 14901]. 13313 14901
Published or last modified on: August 23, 2002
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Tutorial: How to MOO
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Tutorial: How to MOO
introduction | getting started
What is a MOO anyway? A MOO can be thought of as an electronic virtual environment. It is a collection of described locations, objects, and characters, arranged in a discrete, virtual architecture inside a computer's memory. As you traverse the MOO, you navigate your persona through the rooms of this electronic space, typing things like "go library" if, for example, you see a door into a library. Each new room or environment will be described by text (and sometimes with images) on your screen, and you can type "look" to examine things more carefully. Objects that you see can be picked up and manipulated (books can be read, food can be eaten, notes can be written and given to other participants in the MOO). The commands to do these things are basically intuitive and are not difficult to learn. For all you need to get started, click the "getting started" link.
A MOO can be thought of as a site of active, rather than passive, reading. Participation in a MOO involves the same two basic activities as reading and taking notes in a book—as you MOO, you will read, and you will write in response to what you have read. Participants read descriptions of locations, objects, characters, and other participants, and they read what the other characters and participants have to say. Their writing consists of simple commands, and also of dialogue, as they interact with one another and with the objects and characters in the MOO. To use Barthes's term, a MOO demonstrates perhaps the most "writerly" text possible—reading text and interpretive interaction with text are interlocked in ways that are intuitive and immediately apparent to the student. Narrative within a MOO space is intrinsically collaborative, arising from the MOO author's textual space and the user's (reader's) response to that space. "Reading" in a MOO is a significantly experiential activity.
A MOO can be thought of as a playground. Like a playground, a MOO provides space for interaction, directed learning, and play. This space is not an empty tabula rasa; it is organized in ways that suggest or encourage certain types of activity. Much as a real playground's space is subdivided (into sandbox, swing set, jungle gym, etc) a MOO's rooms have unique attributes and qualities, and these spaces contain objects which encourage various types of interaction. Also like a playground, there is no predetermined goal to accomplish in a MOO; there is no way to "win" or "lose. Just as a physical swing set may suggest the activity of swinging, a MOO's spaces and objects only imply certain uses and responses. You can swing on a swing set, or you can invent your own use for the swings that has nothing to do with swinging. The same is true of a MOO's spaces and objects. It provides a venue within which games may be invented and played—it is not itself a single game. Notice that this parallels the activity of literary interpretation in provocative ways. Students can enact and experiment with various responses to the text space of the MOO, and refine and modify their responses in reaction to and collaboration with the interpretive community formed by the other MOO participants. For, like playing on a playground, MOOing is not a solitary activity. Much of what you do inside a MOO is interact with other MOO participants, engage in dialog, discuss, explore, play, learn.
Getting Started
Getting Into the MOO
1. Go to <http://www.rc.umd.edu:7000/>
2. A log-in screen will appear.
You will log in as a Guest. Do not enter anything in the ID or password boxes. The ID box should say "Guest" and the password box should be left blank. Simply click the gray "login" button on the left hand side of the screen.
3. A split screen will pop up (Give it time to load).
On the top are helpful buttons. On the left is the conversation going on. Choose the "normal" radio button to describe actions. Choose "say" to speak in the MOO. Choose "emote" to let your character express an emotion. At the right is what you see in the room. Characters will be represented by an avatar icon. Objects will have representative icons. Doors to other rooms will be represented by an arrow icon.
Registering Your Own Character
To avoid being bumped off of the MOO as a guest, sign up for a character identity. Here's three ways to do it:
1. Before logging in as guest, click on the "Create Account" button at the bottom left-hand frame of your browser. Fill out the New Character Creation Form and send it. Do not use blank spaces in your user ID name.
2. Log in as a guest. Once you are logged in, click the "Request" button at the top of your MOO window. Fill out the New Character Creation Form and send it. Do not use blank spaces in your user ID name.
3. Log in as a guest. Once you are logged in, click your cursor in the bottom left-hand frame of your browser, type "@request," and then follow the directions.
Once you have completed the on-line request process, it will take the server approximately five to ten minutes to process your request and then your new account information will be sent to the e-mail address that you entered in the request.
When requesting a character, please remember that this is an educational MOO and that scholarly exchanges generally work better when others in the MOO know who you are; so, we suggest that you use your real name as your character name. Non-registered users can browse the MOO non-interactively using any Web Browser at <http://www.rc.umd.edu:7000/62/>.
Using MOO Commands: (important commands have an asterisk)
1. *To talk, either click the "say" radio button and type your comment in the bottom left hand corner of the screen in the blank box, or use quotation marks before and after what you want to say in "normal" (default) mode. For example, to say hi, type "hi" then hit return.
2. *To look around at the room, type the word look in the blank box (make sure you are in "normal" or default mode). To examine an object type "examine <object name>". For example, to examine a lake type: examine lake. For an easy way to look and get a basic description of an object, see number six below.
3. To emote, that is to show an expression or action, either click the "emote" radio button and describe your emotion in the blank box, or use a colon before the words expressing your action while in "normal" (default) mode. For example, if I want to smile, I type :smiles.
4. If you see an object and want to take it, type take <object name> (make sure you are in "normal" or default mode). For example, take flower. This allows me to pluck a flower. To drop an object, type drop <object name>, such as drop flower. Note: it is good etiquette to return things where you found them after you are done with the object!
5. At the most basic level of interaction, all you need to do is look and talk. Anything else is extra which you can learn as you gain experience.
6. *The right hand side of the screen has several features. It gives you a description of what you are looking at. You can click on an object and this will allow you to examine the object. Most objects are denoted with an icon looking like a generic blocky object. To look at the whole room type "look" or use the look button on the tool bar at the top of the screen. To move to another room, click the room name next to the door icon.
7. At the top of your screen is a tool bar, which looks like this:
What these buttons do:
About: details of the MOO program
Help: a range of help links from basic maneuvering to MOO programming
Look: shows you the room you are in
Who: shows you what other players are in the MOO
Options: Allows you to create a MOO name, choose a gender, and offer a description of your character
Guide: some basic and not so basic MOO commands
Request:an easy form for requesting a permanent character
Quit: end your MOO session
You will also find helpful hints at Cynthia Haynes and Jan Rune Holmevik's "Beginners Guide to MOOing."
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26 Monkmartyrs of the Zographou Monastery on Mount Athos In the year 1274 at the Council of Lyons (in France), the Byzantine emperor Michael VIII Paleologos decided to buttress his waning power by forming a union with Catholic Rome. This step evoked universal discontent. In 1278, the emperor issued a decree to introduce the Union at Constantinople by forceful measures, if necessary.
The Crusaders pushed out of Palestine and finding refuge in the Byzantine Empire, declared to the emperor their readiness to affirm the power of the Pope by fire and sword, if necessary. In addition, Michael had hired mercenaries, both Turks and Tatars, to enforce his decree.
The emperor despised the monks of Mt. Athos for their opposition. Since he did not want to provoke the Greeks, he decided to vent his spite upon the Athonite Slavs. By Michael’s order, the servants of the Pope descended upon the Bulgarian Zographou monastery. When the demand to accept the Union was presented before the Zographou monks, they refused to listen. They adhered to the doctrines of the Fathers, and fearlessly censured those who accepted the Latin teachings. The majority of the Zographou monks left the monastery, but the most steadfast, twenty-six in number, remained within the monastery tower. These were:Igumen Thomas, and the monks Barsanuphius, Cyril, Michael, Simon, Hilarion, James, Job, Cyprian, Sava, Jacob, Martinian, Cosmas, Sergius, Menas, Joasaph, Joannicius, Paul, Anthony, Euthymius, Dometian, Parthenius, and four laymen.
The holy martyrs for their Orthodox Faith, were burned in the monastery tower on October 10, 1284. (also September 22).
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"language_score": 0.9493745565414429,
"url": "https://oca.org/saints/lives/2013/10/10/108024-26-martyrs-of-the-zographou-monastery-on-mt-athos-at-the-hands-o"
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giri giri - 4 months ago 22
Java Question
What are helper objects in java?
I come across few of the times called helper objects... can anybody elaborate what are those helper objects and why do we need them?
Some operations which are common to a couple of classes can be moved to helper classes, which are then used via object composition:
public class OrderService {
private PriceHelper priceHelper = new PriceHelper();
public double calculateOrderPrice(order) {
double price = 0;
for (Item item : order.getItems()) {
double += priceHelper.calculatePrice(item.getProduct());
public class ProductService {
private PriceHelper priceHelper = new PriceHelper();
public double getProductPrice(Product product) {
return priceHelper.calculatePrice(product);
Using helper classes can be done in multiple ways:
• Instantiating them directly (as above)
• via dependency injection
• by making their methods static and accessing them in a static way, like IOUtils.closeQuietly(inputStream) closes an InputStream wihtout throwing exceptions.
• at least my convention is to name classes with only static methods and not dependencies XUtils, and classees that in turn have dependencies / need to be managed by a DI container XHelper
(The example above is just a sample - it shouldn't be discussed in terms of Domain Driven Design)
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What are the characteristics of Fasciola hepatica?
Quick Answer
The organism known as Fasciola hepatica is a type of fluke, which is a parasitic trematode. Fasciola hepatica infects snails and mammals, causing the disease known as fascioliasis. Because the parasite is often discovered in captive sheep, it is sometimes called the sheep liver fluke. The species lives all over the world.
Continue Reading
Full Answer
These flukes have a complex life cycle that begins in aquatic and semiaquatic snails. When the snail defecates, the flukes exit the snail’s body and take refuge on the stems and leaves of aquatic and terrestrial plants. When mammals eat the contaminated plants, the flukes make their way into the mammals’ digestive systems and ultimately into the liver. People normally acquire sheep liver flukes by ingesting raw watercress or other aquatic plants that are coated with Fasciola hepatica eggs.
Sheep liver flukes are very large flukes, with some reaching up to 30 millimeters in length and 13 millimeters in width. They are lance- or leaf-shaped and feature spines all over their bodies. They are variable in color and each fluke has a small oral disk at one end of its body.
Fascioliasis is easily prevented by cooking or washing vegetables before they are eaten. However, when infections do occur, they are relatively easy to treat and most people recover without long-term consequences.
Learn more about Worms
Related Questions
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"language": "en",
"language_score": 0.9540524482727051,
"url": "https://www.reference.com/pets-animals/characteristics-fasciola-hepatica-308372b647b8645"
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The best way to prevent diphtheria is to get vaccinated. In the United States, there are four vaccines used to prevent diphtheria: DTaP, Tdap, DT, and Td. Each of these vaccines prevents diphtheria and tetanus; DTaP and Tdap also help prevent pertussis (whooping cough). DTaP and DT are given to children younger than seven years old, while Tdap and Td are given to older children, teens, and adults.
Babies and Children
The current childhood immunization schedule [2 pages] for diphtheria includes five doses of DTaP for children younger than seven years old.
Preteens and Teens
The adolescent immunization schedule [2 pages] recommends that preteens get a booster dose of Tdap at 11 or 12 years old. Teens who did not get Tdap when they were 11 or 12 years old should get a dose the next time they see their doctor.
Adults should get a dose of Td every 10 years according to the adult immunization schedule [2 pages]. For added protection against whooping cough, any adult who never received a dose of Tdap should get one as soon as possible. The dose of Tdap takes the place of one of the Td shots.
Learn more about diphtheria vaccines.
Top of Page
Related Pages
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"language": "en",
"language_score": 0.9081795811653137,
"url": "https://www.cdc.gov/diphtheria/about/prevention.html"
}
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Train Journey
The children make and play a board game to practise vocabulary related to transport.
Author: Cristina Casado Whittaker and Tracey Chapelton
To introduce and revise vocabulary related to transport
Train Journey Worksheet, pencil, coloured pencils, scissors, glue, backing card
Language focus
Means of transport: bus, boat, car, motorbike, plane, train, bike, helicopter, actions: fly, go, ride, run, swim, walk
Show more
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"edu_score": 3.859375,
"fasttext_score": 0.025613367557525635,
"language": "en",
"language_score": 0.789683997631073,
"url": "http://www.macmillanelt.es/teachers_corner/train-journey/"
}
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Potlatch is a traditional Indian ceremony that was performed traditionally by the Indian communities. The ceremony was characterized by elaborate song and dance as well as wealth redistribution and sharing of belonging. There were also several forms that this ceremony could take, with ceremonies being performed during the birth, naming, death related ceremonies an in many other forms of rights of passage. The ceremony therefore had tremendous influence to the way of life of the people as it cut across various cultural practices hence defining the cultures of regions where it was practiced.
As noted by Donald, (2007), Potlatch ceremonies had various functions in aboriginal societies in British Columbia. To begin with, the ceremony provided the cohesive forces that bound the members of the society together. The aboriginal group of the British Columbia had a unique culture that ensured that various aspects of the society were well taken care off. The ceremonies were used to reinforce values and norm to the society members especially su to the fact that the ceremony had a huge cultural connotation. The ceremony also integrated the basic survival tenets of the society whereby various aspects of the society such as economic aspects were incorporated and managed.
Potlatch ceremonies also were seen to unite the community with its ancestry as the ceremonies provided ample grounds where the original ancestors of a specific cultural group were hailed and described. As noted by Olson, (2008), creatures such as dzunukwa who are ancestral parents of supernatural creatures were only noted during potlatch ceremonies. The community was therefore informed on its origin from the ceremonies and taught on how to hail its founders. The other function that the ceremonies performed were humanitarian duties as the ceremony by itself was based on reciprocity of wealth. Some cultures such as the Kwakwaka'wakw used these ceremonies to achieve status of prestige and social clout especially due to the emphasis of reciprocity and introducing the means to measure ones wealth. In cultures such as the Kwakwaka'wakw, wealth and personal status were measured not by the amount of wealth that a person held but through the amount of goods that a person shared with the others (Aderkas and Hook, 2005). The ceremony therefore had the function of economic stratification of its members, redistributive purposes as well as cultural purposes.
Potlatch ceremonies cut across various dimensions of social life. The ceremony had economic dimension where by it was conducted majorly during the winter seasons as they were considered better as the warmer months were spared for the sake of property or wealth generation. The ceremonies also acted as ways of showing what people have acquired over the warmer months. Religiously, the ceremonies were used to acknowledge the duties and to sensitize the communities on the goodness of the supernatural creature, to thank the supernatural creatures as well as to offer gratitude's to this creatures. The ceremony also provided the community with an avenue for socializing the younger ones into the aboriginal community's ways of life. In such ceremonies, the younger people were reminded of their lineage, their origins and ways of worshiping. Day to day cultural aspects were also taught to the younger generation where enculturation took place making the young community members to learn more on the need for wealth reciprocity and sharing, a key fact pillar to the potlatch ceremonies.
Bracken, (2003), cites that the potlatch ceremonies were useful tools to sensitize the community members especially the younger ones on the importance of brotherhood. The ceremonies transmitted the values of caring for one another especially through reciprocity. Sharing of various gifts, both materials and non material were a key pillar to the ceremonies and young members of the society were taught on how to share with one another. The ceremonies also taught the aborigines on norms and values of hard work. As noted by Olson, (2008), the ceremonies were majorly conducted on winter to allow the community members to utilize the warmer months for wealth generating activities. The ceremony also reinforced the values of norms and hard work by providing how hard work was measured and praised through providing avenues of appreciating those who produce more. The ones who had more goods to share were given greater clout hence encouraging the society to produce more to ensure that each member has something to share out.
Despite the traditional significance played by the ceremony to the communities that practiced these ceremonies, the ceremony was outlawed in 1885 by the mainstream inhabitants of the British Columbia. Many reasons have been advanced towards explaining why the ceremony was outlawed. As cited by McKee, (2000), one of the major reasons why the ceremony was outlawed was to pave way for Christian missionaries who considered the ceremony a huge block towards converting the Indians into Christianity. They therefore saw the ceremony as a stumbling block and sought the help of administrative units to withdraw the ceremony. Another reason why the ceremony was outlawed was that the mainstream society saw the ceremony as redundant in the age of civilization. As noted by Aderkas and Hook, (2005), the ceremony was seen as a huge block towards ensuring that that the aborigines adopted civilization and thus they opted to have the ceremony terminated. The ceremony was seen as the force for solidarity against civilization among the aborigines' societies and thus they were forced to use the legal channel to ensure that they weakened this force that united the community to its culture against civilization.
The ceremony also contradicted the norms of the British Columbia majority who were Europeans. To begin with the ceremony seemed to have a socialistic ideology that was considered retrogressive to the general development. McKee, (2000), asserts that the potlatch ceremony encouraged sharing of resources and failed to recognize wealth, a fact that was considered detrimental economically by the main stream society. The fact that the ceremony contradicted the economic institution of the mainstream European societies was recipe for conflict among the two societies. The culture of this ceremony also contradicted the main religious view of the European societies. The culture advocated for supernatural beings that were unacceptable among the mainstream societies that were mainly Christian prompting the religious institution of the mainstream cultures engineer the outlawing of this ceremony. The religious groups therefore preferred to have this ceremony and its culture outlawed as they saw it as the stumbling block towards conversion of the Indians into Christianity.
Today, the ceremony is still being performed. However, the performance of the potlatch ceremonies is more of a ceremonial nature and an attempt of the aborigine's community to preserve their culture and ancient practices. The initial meaning of sharing are no longer evident in this ceremony as the ceremony is more ceremonial and a way of sowing the younger generations what used to happen prior to civilization. The functions of potlatch today therefore are purely ceremonial and are geared towards ensuring that the community does not loose its original culture. The ceremony therefore is a pale shadow of its former self, acting only as a reminder with no reinforcing norms as it used to be in the 19th century and centuries prior to this period. The legal restrictions also are no longer active as the younger educated Indians did not copy the ceremony's acts that were considered retrogressive.
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Pooping. Everyone does it, right? Might as well make it count. Here are some ways that poop made a difference in the world.
10. Poop shows when new members of a species are introduced
Just recently genetic testing on wolf scat in the Isle Royale National Park showed that what had previously thought to be an isolated wolf population had actually benefitted from an immigrant from Canada. The new pooper, known because of his light fur as The Old Gray Guy, had sired over 50 offspring and provided insight into the complicated results of introducing new animals into inbred populations.
9. Mammoth poop eases comet fears
People worry that a comet killed off the mammoth population, and that another comet could do the same to us. Ancient mammoth poop indicates, though, that they were actually killed off by a fungus and bug poop (two poop accomplishments in one), that they ingested along with plants.
8. Ancient poop may kill us
Now-extinct giant animals used to roam the arctic, and their 'organic matter' has been sealed in by permafrost. With modern climate change unearthing that material, a big steaming pile of carbon dioxide and methane may be released into the atmosphere. Let's keep it cold, people.
7. Poop fueled US expansion in the Pacific
In the 1800s, before chemical fertilizers, people used nitrogen-rich guano to help grow crops. Because guano was often to be found in small islands in the Pacific that only birds landed on, and because exporters of guano were driving up the price, the US passed the Guano Islands Act. This allowed private citizens to claim any uninhabited island for the purposes of mining guano. The resulting rush, and the fact that the US could claim land it had no intention of incorporating into the union, solidified US presence in the Pacific.
6. Whale poop saves the oceans.
Whales are not just the gentle giants of the sea, they're also quite possibly the only animals that can regularly poop upwards. Their poop floats, so it goes towards the surface of the ocean and spreads. Sounds disgusting, but it turns out that whale poop provides important nutrition for plankton and other tiny animals that form the base of the ocean ecology.
5. Hyena poop provides the earliest sample of human hair.
Did you know that a carnivore's poop is a wonderful preservative for hair? Did you want to know? The oldest sample of human hair - even though it is completely fossilized, comes from ancient hyena dung. Scientists don't know whether the hyena hunted early humans or just scavenged off dead ones, but the hair is between 200,000 and 250,000 years old.
4. Chinchilla poop lets scientists trace the rainfall of the driest desert on earth.
Often scientists use plant matter or fossilized trees to find out how much rain has fallen over past years. There isn't much plant matter to be found in the Atacama desert. What can be found is in chinchilla 'middens'. Middens are whatever scraps the chinchilla doesn't need anymore, covered in chinchilla poop pellets and glued together with urine. Since the poop and urine pretty much seal the midden, scientists can determine what plants the rodent was feeding on. As part of its sealing process, the poop soaks up moisture from the air. The size of the poop pellets can tell scientists how much it rained that year. And since poop is organic, they can carbon date the middens and reconstruct the climate history of the Atacama.
3. Poop, and dogs' willingness to sniff it, can prevent the spread of avian flu
Dogs have been shown to have noses sensitive enough to sniff out cancer in other animals' bodies. They can fairly easily smell infected feces, and the American Chemical Society announced plans to use the noses of dogs and mice to sniff out feces of imported or wild animals and trace movements of avian flu. Once scientist know how an infected population moves, they can work on preventing contact between that population and other animals - and between the population and humans.
2. Poop lets scientists trace human movements
Human coprolites (fossilized poop) have been found in Arizona, Oregon, have been helpful in tracing where humans have been over the years. Granted, it's hard to distinguish fosslized poop from rock, and fossilized human poop from any other kind of fossilized poop, so the finds are controversial, but let's raise a glass to those celebrated squatters who made their presence known thousands of years later.
1. Poop transplants can save lives!
Doctors are doing something they tactfully call a 'probiotic infusion' on patients with gastrointestinal problems. The gut has important bacteria in it that help people digest food and fight off infection. If those die off due to sickness or continued use of anitbiotics, a person can be in real trouble. Give them some healthy poop through a tube in the nose, and they live on - probably only wishing they were dead once in a while.
Via Michigan Tech University, AAAS, Green Diary, MSN, Basement Geographer, Discovery, MSNBC, Discovery, AAAS, and Fast Company.
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Unit-2: The Nationalist Movement in Indo-China – History NCERT Solution Class-10
Unit-2: The Nationalist Movement in Indo-China
Intext Solutions:-
Page- 35
Q.1:- Imagine you are a student in the Tonkin Free School in 1910. How would you react to
• what the textbooks say about the Vietnamese?
• what the school tells you about hairstyles?
Page- 38
Q.1:- What does the 1903 plague and the measures to control it tell us about French colonial attitude towards questions of health and hygiene?
Page- 41
Q.1:- What ideas did Phan Boi Chu and Phan Chu Trinh share in common? What did they differ on?
Exercise Solutions:-
Q.1:- Write a note on:-
(a) What was meant by ‘civilizing mission’ of the Colonizers?
(b) Huynh Phu So
Q.2:- Explain the following
(a) Only one-third of students in Vietnam would pass the school-leaving examination.
(b) The French began building canals and draining lands in the Mekong delta.
(c) The Government made the Saigon Native Girls School takes back the students it had expelled.
(d) Rats were most common in the modem, newly built areas of Hanoi.
Q.3:- Describe the ideas behind the Tonkin free school. To what extent was it a typical example of colonial ideas in Vietnam?
Q.4:- What was Phan Chu Trinh objective for Vietnam? How were his ideas different from those of Phan Boi Chau?
Discussion Solutions:-
Q.1:- With reference to what you have read in this chapter, discuss the influence of China on Vietnam’s culture and life.
Q.2:- What was the role of religious groups in the development of anti-colonial movement in Vietnam?
Q.3:- Explain the causes of the US involvement in the war in Vietnam. What effect did this involvement have on the life within the US itself?
Q.4:- Write an evaluation of Vietnamese war against the US from point of
(a) Porter in the Ho Chi Minh Trail
(b) A woman solider
Q.5:- What was the role of women in the anti-imperial struggle in Vietnam? Compare this with the role of women in the nationalist struggle in India.
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Precal HW problem
1. Oct 19, 2006 #1
HI guys, I'm really confusing about this Q., and I hope you guys can give me some help. :smile:
- Find the perimeter and the area of a regular pentagon inscribed in circle of radius 9.
2. jcsd
3. Oct 20, 2006 #2
Break the inscribed pentagon into something simpler, such as triangles.
4. Oct 20, 2006 #3
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Draw lines from the center of the circle to the vertices of the pentagon. What is the angle between these lines?
5. Oct 20, 2006 #4
I just figured out how to work on the problem. thx everyone for helping me.
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Fraction Monsters
Students create a fraction monster from a circle cut into equal slices, make a fraction monster form some of the slices and tell the amount of slices of the circle they used to make the monster. They write a story about their monster and share it with the class.
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Robert W.
Robert W., Teacher
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The Rise of the Dutch Republic, 1576
Language: English
Wordcount: 23,441 / 77 pg
Flesch-Kincaid Reading Ease: 47.9
LoC Category: D
Downloads: 209 5186
Genre: History
rural population. On the whole, there was a tolerably fair representation of the whole nation. The people were well and worthily represented in the government of each city, and therefore equally so in the assembly of the estates. It was not till later that the corporations, by the extinction of the popular element, and by the usurpation of the right of self-election, were thoroughly stiffened into fictitious personages which never died, and which were never thoroughly alive.
At this epoch the provincial liberties, so far as they could maintain themselves against Spanish despotism, were practical and substantial. The government was a representative one, in which all those who had the inclination possessed, in one mode or another, a voice. Although the various members of the confederacy were locally and practically republics or self-governed little commonwealths, the general government which they, established was, in form, monarchical. The powers conferred upon Orange constituted him a sovereign ad inter
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To support and help the actions taken for the survival of the critically endangered Balkan lynx
The Balkan lynx population is the most endangered of all autochthonous Lynx lynx populations. This is the more alarming as it most probably concerns even an own subspecies Lynx lynx martinoi.
The present distribution of the Balkan lynx is restricted to the southwest Balkans, mainly the border areas between Macedonia and Albania, spreading north into Montenegro and Kosova. The population is estimated to be less than 100 individuals. Biology, ecology and history of the Balkan lynx are not well understood or documented, but obvious threats have been direct persecution in the past, decline of prey populations, and loss and fragmentation of habitat.
The aim of the Balkan Lynx Recovery Programme is to secure the survival of the population through a series of protected areas and improved wildlife management within and outside the PAs. To do so, we need to generate a set of baseline information and to establish a reliable monitoring programme. This implies a strong partnership between governmental and non-governmental institutions on national and international level, increased public awareness and public involvement, and – above all – capacity building in nature conservation, wildlife research, and management.
1. Balkan Lynx Conservation Compendium - http://www.catsg.org/balkanlynx/
2. http://www.euronatur.org/The-Balkans.450.0.html
3. http://news.bbc.co.uk/2/hi/europe/6114962.stm
4. Balkan lynx population - http://www.kora.ch/en/proj/elois/online/populations/balkan/main.htm
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Click for: CSSHS Archive Main Page
Vol. XIII • 1991
Christianity in Literary Creation: Chateaubriand and Dostoevsky
Andrea Link
Many contrasts can be drawn between the lives of Francois Rene de Chateaubriand (1768-1848) and Feodor Dostoevsky (1822-1881): they came from different epochs, cultures and family traditions, as well as having opposing temperaments. Chateaubriand grew up as an aristocrat and Royalist in Combourg during the dawn of the French Revolution. Throughout his life, sentiments of melancholy and disillusionment about the world weighed heavily upon his heart. A founding father of French Romanticism, he lived as a Romantic hero whose suffering became a source of "self-limiting pride" (Jackson, p.29).
Dostoevsky, a descendant of the lower nobility, was brought up modestly in Moscow. He grew up under the shadow of the Decembrist Insurrection of 1825, which prompted Tsar Nicholas I to rule with severe military and bureaucratic discipline. In contrast to Chateaubriand, Dostoevsky had an energetic temperament and a "nervous, self-illuminating pride" (Jackson, p.29). Instead of trying to escape the despair of this world like Chateaubriand, Dostoevsky attempted to understand it through a profound examination of himself, those around him, and their environment. As a result, Dostoevsky developed as a post-Romantic or Romantic-Realist writer.
These authors do, however, share a common thread: their spiritual and religious developments follow similar paths. Each was brought up in a religious tradition; Chateaubriand was a Roman Catholic and Dostoevsky a Russian Orthodox. Their mothers served as the faithful, devout, religious role models of the family, and it was their faith that planted seeds of faith in the hearts of the young writers.
Yet as young adults, both Chateaubriand and Dostoevsky experienced periods of doubt. Instead of holding strong to their Christian traditions, they became ardent dreamers who quested after ideal notions such as beauty and justice. Their longings to find truth drew them to learn about the current ideologies of their age. For example, Chateaubriand embraced some of the ideas of Rousseau and Dostoevsky became involved in a Utopian-Socialist group. Their romantic quests, however, left both Chateaubriand and Dostoevsky feeling disappointed and disillusioned when they realized these current ideologies did not bring them to the truth.
Both men then experienced humiliating poverty and mental suffering when they were exiled from their countries, As an aristocrat, Chateaubriand was an enemy to the French Revolution and to save his life he became en emigré in England in the early 1790's. Tsar Nicholas I exiled Dostoevsky in 1849 for his political involvement. As a result of extreme suffering, both writers had conversion experiences which led them to embrace the Christian faith. When Chateaubriand's mother died, the grief caused him to accept the faith of his mother, Similarly, Dostoevsky, facing the horrors of prison life, experienced a rebirth of his soul."
Though both underwent similar transformations of their hearts through their faith in Christ, Chateoubriand and Dostoevsky developed different Christian world-views. Chateaubriand developed a dualistic view of Christianity. The fallen world, which is ruled by Satan, remains separated from God's spiritual world, the kingdom of heaven. Thus life in this sinful world is utterly painful, despairing and meaningless. The ideals of Christianity, including love, peace and joy, will only be realized in heaven. Chateaubriand believed that "the Christian always looks upon himself as no more than a pilgrim travelling here below through a vale of tears and finding no repose till he reaches the tomb" (Chateaubriand, 1976, p.297). Only Christians can be hopeful that they will die soon and enter into heaven, where they will experience redemption and the eternal bliss of communing With God.
Dostoevsky, in contrast to Chateaubriand, developed a reconciled view of Christianity. This world is fallen and Christians will ultimately experience the full abundance of the kingdom of heaven when they die. However, a Christian can begin to experience communion with God even while living in a sinful world. For Dostoevsky, Christ's statement, "Repent, for the kingdom of heaven is at hand" (Matthew 4:17) meant that a reconciliation with God began once a person repented and accepted Christ's sacrificial death for their sins. Dostoevsky believed Christians could begin to experience the kingdom of heaven within their hearts. God's spirit, love and power can begin to sanctity and transform the hearts of those who have faith.
While both men embraced the Christian faith, questions of doubt continually challenged heir convictions, P. L. Jackson writes that Chateaubriand and Dostoevsky shared "a paradoxical affirmation of faith " (Jackson, p.30). At the end of his life Chateaubriand stated, "As it grew, my religious conviction has devoured my other convictions, (but) in this world there is no more believing Christian and no more doubting man than I" (ibid.). In a similar fashion, Dostoevsky wrote in 1854: "If somebody proved to me that Christ was outside the truth, and it really were so that the truth was outside Christ, then I would rather remain with Christ than with the truth l am a child of the age, a child of lack of faith and doubt till now and (this I know) this will be true till the coffin closes over... " (ibid.). Since Chateaubriand and Dostoevsky understood the dynamics of being both a strong believer and a wavering doubter, they were able to vividly portray this inner baftie which their characters experience when they are faced with the Christian faith (e.g. Chactas, Rene and Raskolnikov).
Dostoevsky and Chateaubriand's own spiritual struggles consequently helped them debate the ideologies of their respective times which were undermining Christianity. Since Chateaubriand and Dostoevsky believed that their countries were facing spiritual crises, they saw their mission as apologists of the Christian faith.
Chateaubriand grew up during the rise of religious doubt and atheism of the Enlightenment, as he described in Le Genie du Christianisme: "Religion was attacked with every kind of weapon, from the pamphlet to the folio, from the epigram to the sophism. No sooner did a religious book appear than the author was overwhelmed with ridicule, while works which Voltaire was the first to laugh at among his friends were extolled to the skies" (Chateaubriand, 1899, p.124). Many philosophes, such as Denis Diderot, Jean le Pond d'Alembert and Voltaire, were skeptical of the Christian faith because they believed it was based on superstition and irrationality. Enlightenment thinkers assumed that the problems of humanity and society could be solved simply through the application of laws and reforms based on human reason. Many during the "Age of Reason aspired to positivism and scientism, and not to faith in God, as the hope for humanity. When the French Revolution broke out in 1789, angry revolutionaries destroyed stained glass windows, religious statues and entire cathedrals to make the statement that the Catholic Church must be extirpated since it represented the oppression and corruption of the fallen monarchy.
Chateaubriand debated against the notion of the Enlightenment that humanity is by nature rational, as he said, "Man's heart is the toy of everything, and no one can tell what frivolous circumstance may cause its joys and its sorrows (Chateaubriand, 1899, p.124). He vehemently disagreed with the idea that rational reforms would solve humanity's problems because he saw the inhuman violence of the French Revolution, Chateaubriand believed it was his mission to show that Chris- tianity was a divinely inspired religion. He argued that the aesthetic beauty of Christianity including the mystical rituals and the ornate cathedrals proved that only God could have inspired Christianity. Through his writings Chateaubriand called France to return to its Christian faith, values and traditions.
During the late eighteenth and early nineteenth centuries the skepticism of the Enlightenment had also permeated the ideologies of the Russian intelligentsia. Atheistic thought became prevalent among the forefathers of Russian socialism (who also founded Russian literary criticism), including Vissarion Belinsky. Alexander Herzen, Nicolay Chernyshevsky and Nicolay Dobrolyubov. They believed in the Western European ideals of positivism, scientism, materialism and utilitarianism.
Through his works, such as Notes from fhe Underground and Crime and Punishment, Dostoevsky argued against the Enlightenment ideal that humanity is rational and perfectible, and that all knowledge can be ascertained through science. For Dostoevsky, humanity's only salvation is through the Christian faith; he saw the rejection of God and Christ as dangerous since it caused people to "engage in the impossible and self- destructive to transcend" their condition (Frank, 1986, p.198). Dostoevsky claimed that the spiritual crisis in Western Europe would eventually lead to its decline and self-destruction, and that the Russian Orthodox faith would be Europe's saving grace. Like Chateaubriand, Dostoevsky argued that the aesthetic beauty and moral perfection of Christianity proved that God divinely inspired it, Thus, Dostoevsky's evangelistic mission was to call his country to return and stay true to its Orthodox heritage.
Chateaubriand and Dostoevsky incarnated their defense of Christianity through their women characters, Atala and Amelia in Chateaubriand's stories Ataia and Rene, and Sonia in Dostoevsky's novel Crime and Punishment embody the Christian faith. Chateaubriand and Dostoevsky's symbolization of women as redemptive figures can be explained partially because women played a major role in their own conversion to Christianity. Their mothers were the guardians of religious faith since they passed the faith on to their children. In addition, the feminine soul has been traditionally depicted in literature as embodying the Christian virtues of compassion, self- sacrifice, gentleness, faithfulness, devotion and love.
Chateaubriand and Dostoevsky used these characters to defend the idea that God's transcendental truths are not revealed through human reason, Atala, Amelia, and Sonia are women whose passionate faith dominates their reason, yet they have God's wisdom. Chateaubriand and Dostoevsky depict the faith of these women as divinely beautiful, which coincides with their view of the aesthetic perfection of Christianity as the basis for its divine inspiration.
Chateaubriand and Dostoevsky's portrayal of these women does, however, differ because of their contrasting Christian world-views. Atala and Amelia long for their death so that they can leave the despair of this world and enter into heaven. Atala and Amelia's carnal desires, especially the desire to love a man, torture them because they believe they are evil and inferior to a spiritual longing for God. They hope for the day when they will be freed from the yearnings of their flesh. Only their spiritual reunion with God in heaven will alleviate the ache in their hearts to be deeply loved.
Sonia, on the other hand, sees that her eternal life has begun on earth, so her faith in God gives her inspiration and hope amidst the pain and sorrow she faces. Her communion with God gives her the strength to carry on, even though she faces the humiliation of poverty and prostitution. Sonia is aware of her sinful nature, yet her acceptance of God's redemption allows her to experience His unconditional love and compassion while in a fallen world.
Atala, Amelia and Sonia all serve as messengers of God's truth for the unbelieving male characters, Chactus, Rene and Paskolnikov. While Atala and Amelia communicate their relentless faith to Chactus and Rene, their testimonies do not have a transforming effect upon them. Chactus and Rene are bound in an earthly world which prevents them from experiencing God's spiritual and eternal realm.
In contrast, Sonia, as the messenger of God's salvation, leads Raskolnikov to faith and salvation. Her words, prayers and actions reflect God's love and forgiveness, and it is her testimony that helps engender a change in Raskolnikov's heart. According to Dostoevsky's Christian world-view, God's spirit can transform the human heart in a fallen world. Thus, Chateaubriand and Dostoevsky respond to the spiritual crises in their countries through their literary creations. These two writers used feminine voices of faith in the hope of combating the growing skepticism of their times.
Francois R. Chateaubriand, Les Memoires d'Outre Tombe. Paris: Garnier Frères, Libraires-Éditeurs, 1899.
Francois P. Chateaubriand, The Genius of Christianity, Charles White, translator New York Howard Fertig. 1976.
Joseph Frank, Dostoevsky The Seeds of Revolt, 1821-1849. Princeton: Princeton University Press, 1986.
Robert Louis Jackson, "Chateaubriand and Dostoevsky: A Posing Problem," Scando- Slovico, Tomus xii. Copenhagen: Munksgaard, 1966.
"Christianity in Literary Creation: Chateaubriand and Dostoevsky"
CSSHS • Creation Social Science & Humanities Society • Quarterly Journal
Main Page: CSSHS Archives
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