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https://en.wikipedia.org/wiki/Nicolaes%20Tulp
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Nicolaes Tulp (9 October 1593 – 12 September 1674) was a Dutch surgeon and mayor of Amsterdam. Tulp was well known for his upstanding moral character and as the subject of Rembrandt's famous painting The Anatomy Lesson of Dr. Nicolaes Tulp.
Life
Born Claes Pieterszoon, he was the son of a prosperous merchant active in civic affairs in Amsterdam. From 1611 to 1614 he studied medicine in Leiden. When he returned to Amsterdam he became a respected doctor and in 1617 he married Aagfe van der Voegh. An ambitious young man, he adopted the tulip as his heraldric emblem and changed his name to Nicolaes (a more proper version of the name Claes) Tulp. He began working in local politics as city treasurer, and in 1622, became a magistrate in Amsterdam.
Career as a physician
The career of Tulp matched the success of Amsterdam. As the population of Amsterdam grew from 30,000 in 1580 to 210,000 in 1650, Tulp's career as a doctor and politician made him a man of influence. He drove a small carriage to visit all the patients. Thanks to his connections on the city council, in 1628 Tulp was appointed Praelector Anatomiae at the Amsterdam Guild of Surgeons. His wife died in the same year, leaving him with five young children. In 1630 he married his second wife, the daughter of the mayor of Outshoorn. They had three children.
It was Tulp who examined and signed the fitness reports for the first Dutch settlers on the island of Manhattan, and his signature was found on these in the long-lost archives of the Dutch settlement uncovered in the 1980s in the basement of the New York public library.
In his job, Tulp was responsible for inspections of apothecary shops. Chemists in Amsterdam had access to an enormous amount of herbs and spices from the East, thanks to the new shipping routes. It became a successful trade and in 1636 there were 66 apothecaries in Amsterdam. Shocked at the exorbitant prices asked for useless anti-plague medicines (Amsterdam was severely hit by the plague in 16
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https://en.wikipedia.org/wiki/Bond%20valence%20method
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The bond valence method or mean method (or bond valence sum) (not to be mistaken for the valence bond theory in quantum chemistry) is a popular method in coordination chemistry to estimate the oxidation states of atoms. It is derived from the bond valence model, which is a simple yet robust model for validating chemical structures with localized bonds or used to predict some of their properties. This model is a development of Pauling's rules.
Method
The basic method is that the valence V of an atom is the sum of the individual bond valences vi surrounding the atom:
The individual bond valences in turn are calculated from the observed bond lengths.
Ri is the observed bond length, R0 is a tabulated parameter expressing the (ideal) bond length when the element i has exactly valence 1, and b is an empirical constant, typically 0.37 Å.
Another formula for has also been used:
Theory
Introduction
Although the bond valence model is mostly used for validating newly determined structures, it is capable of predicting many of the properties of those chemical structures that can be described by localized bonds
In the bond valence model, the valence of an atom, V, is defined as the number of electrons the atom uses for bonding. This is equal to the number of electrons in its valence shell if all the valence shell electrons are used for bonding. If they are not, the remainder will form non-bonding electron pairs, usually known as lone pairs.
The valence of a bond, S, is defined as the number of electron pairs forming the bond. In general this is not an integral number. Since each of the terminal atoms contributes equal numbers of electrons to the bond, the bond valence is also equal to the number of valence electrons that each atom contributes. Further, since within each atom, the negatively charged valence shell is linked to the positively charged core by an electrostatic flux that is equal to the charge on the valence shell, it follows that the bond valence is al
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https://en.wikipedia.org/wiki/Windows%20Filtering%20Platform
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Windows Filtering Platform (WFP) is a set of system services in Windows Vista and later that allows Windows software to process and filter network traffic. Microsoft intended WFP for use by firewalls, antimalware software, and parental controls apps. Additionally, WFP is used to implement NAT and to store IPSec policy configuration.
WFP relies on Windows Vista's Next Generation TCP/IP stack. It provides features such as integrated communication and per-application processing logic. Since Windows 8 and Windows Server 2012, WFP allows filtering at the second layer of TCP/IP suite.
Components
The filtering platform includes the following components:
Shims, which expose the internal structure of a packet as properties. Different shims exist for protocols at different layers. WFP comes with a set of shims; users can register shims for other protocols using the API. The in-built set of shims includes:
Application Layer Enforcement (ALE) shim
Transport Layer Module (TLM) shim
Network Layer Module (NLM) shim
RPC Runtime shim
Internet Control Message Protocol (ICMP) shim
Stream shim
Filtering engine, which spans both kernel-mode and user-mode, providing basic filtering capabilities. It matches the data within a packetas exposed by the shimsagainst filtering rules, and either blocks or permits the packet. A callout (see below) may implement any other action as required. The filters operate on a per-application basis. To mitigate conflicts between filters, they are given weights (priorities) and grouped into sublayers, which also have weights. Filters and callouts may be associated to providers which may be given a name and description and are essentially associated to a particular application or service.
Base filtering engine, the module that manages the filtering engine. It accepts filtering rules and enforces the security model of the application. It also maintains statistics for the WFP and logs its state.
Callout, a callback function exposed by a filterin
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https://en.wikipedia.org/wiki/Bob%20Sabiston
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Bob Sabiston (born 1967) is an American film art director, computer programmer, and creator of the Rotoshop software program for computer animation. Sabiston began developing software as an undergraduate and then graduate researcher in the MIT Media Lab from 1986 to 1991. While at MIT, and also after moving to Austin, Texas, in 1993, Sabiston used his 2D/3D software to create several short films, including God's Little Monkey (1994), "Beat Dedication" (1988), and "Grinning Evil Death" (1990). "Grinning Evil Death" was widely seen on the first episode of MTV's "Liquid Television" show. "God's Little Monkey" won the Prix Ars Electronica Golden Nica award for 1994.
In 1997, he developed his interpolating rotoscope program, Rotoshop, for an animation contest sponsored by MTV. The software was used to produce a series of 25 30-second interstitials in New York, collectively entitled "Project Incognito." He moved back to Austin in 1998 and with the help of local artists made the short film "RoadHead." This was followed in 1999 by short "Snack and Drink" in collaboration with Tommy Pallotta. "Snack and Drink" won several film festival awards and resides in the MOMA video collection. The shorts collection "Figures of Speech" followed in late 1999, for PBS. In 2000, Sabiston hired thirty graphic artists in the Austin area to help make Richard Linklater's film Waking Life.
After Waking Life Sabiston spent several years making more rotoscoped short films, including "Yard", "Earthlink Sucks", "Grasshopper". He directed a series of shorts for the PBS show "Life360". In 2003 he directed a short segment for the Lars von Trier film The Five Obstructions. Both "Grasshopper" and "The Five Obstructions" were shown at the Sundance Film Festival in 2004.
In 2004 Sabiston was hired as Head of Animation for Richard Linklater's A Scanner Darkly. He modified the software substantially for the film. Since 2005 he has also directed the "Talk to Chuck" campaign of animated adverti
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https://en.wikipedia.org/wiki/Free-standing%20Mathematics%20Qualifications
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Free-standing Mathematics Qualifications (FSMQ) are a suite of mathematical qualifications available at levels 1 to 3 in the National Qualifications Framework – Foundation, Intermediate and Advanced.
Educational standard
They bridge a gap between GCSE and A-Level Mathematics. The advanced course is especially ideal for pupils who do not find GCSE maths particularly challenging and who often have extra time in their second year of GCSEs, having taken their Maths GCSE a year early. The qualification is commonly offered in private schools and is useful in allowing pupils to determine whether or not to pursue maths in subsequent stages of their schooling.
The highest grade achievable is an A. An FSMQ Unit at Advanced level is roughly equivalent to a single AS module with candidates receiving 10 UCAS points for an A grade. Intermediate level is equivalent to a GCSE in Mathematics. Coursework is often a key part of the FSMQ, but is sometimes omitted depending on the examining board.
Exam boards
The only examining board currently offering FSMQs is OCR.
Edexcel withdrew the qualification, the last exam being held in June 2004. AQA also withdrew the pilot advanced level FSMQ, the last exam being in June 2018, and a final re-sit opportunity in June 2019.
Examples
Additional Mathematics/AdMaths (OCR) (No coursework)
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https://en.wikipedia.org/wiki/Average%20propensity%20to%20save
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In Keynesian economics, the average propensity to save (APS), also known as the savings ratio, is the proportion of income which is saved, usually expressed for household savings as a fraction of total household disposable income (taxed income).
The ratio differs considerably over time and between countries. The savings ratio for an entire economy can be affected by (for example) the proportion of older people (as they have less motivation and capability to save), and the rate of inflation (as expectations of rising prices can encourage people to spend now rather than later) or current interest rates.
APS can express the social preference for investing in the future over consuming in the present.
The complement (1 minus the APS) is the average propensity to consume (APC).
Low average propensity to save might be the indicator of a large percentage of old people or high percentage of irresponsible young people in the population.
With income level changes, APS becomes an inexact tool for measuring these changes. So, the marginal propensity to save is used in these cases.
Characteristics of APS
Mathematics
From the equation:
APS is calculated from the amount of savings as a fraction of income.
APS can be calculated as total savings divided by the income level for which we want to determine the average propensity to save.
Example 1: The income level is 90 and total savings for that level is 25, then we will get 25/90 as the APS.
Average propensity to save can not be greater than or equal to 1, but APS can be negative, if income is zero and consumption has a positive value.
Example 2: The income is 0 and consumption is 20, so the APS value will be -0.2.
Average propensity to save is decreasing
As is a fraction of income, an increase in income would make the proportion of saving lower. Also income rises faster than savings so APS tens to decrease as income increase.
Marginal propensity to save (MPS)
Marginal propensity to save is the proportion of an incr
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https://en.wikipedia.org/wiki/Solaris%20Containers
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Solaris Containers (including Solaris Zones) is an implementation of operating system-level virtualization technology for x86 and SPARC systems, first released publicly in February 2004 in build 51 beta of Solaris 10, and subsequently in the first full release of Solaris 10, 2005. It is present in illumos (formerly OpenSolaris) distributions, such as OpenIndiana, SmartOS, Tribblix and OmniOS, as well as in the official Oracle Solaris 11 release.
A Solaris Container is the combination of system resource controls and the boundary separation provided by zones. Zones act as completely isolated virtual servers within a single operating system instance. By consolidating multiple sets of application services onto one system and by placing each into isolated virtual server containers, system administrators can reduce cost and provide most of the same protections of separate machines on a single machine.
Terminology
The name of this technology changed during development and the pre-launch public events. Before the launch of Solaris Zones in 2005, a Solaris Container was any type of workload constrained by Solaris resource management features. The latter had been a separate software package in earlier history. By 2007 the term Solaris Containers came to mean a Solaris Zone combined with resource management controls.
Later, there was a gradual move such that Solaris Containers specifically referred to non-global zones, with or without additional Resource Management. Zones hosted by a global zone are known as "non-global zones" but are sometimes just called "zones". The term "local zone" is specifically discouraged, since in this usage "local" is not an antonym of "global". The global zone has visibility of all resource on the system, whether these are associated with the global zone or a non-global zone. Unless otherwise noted, "zone" will refer to non-global zones in this article.
To simplify terminology, Oracle dropped the use of the term Container in Solaris 11, and has
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https://en.wikipedia.org/wiki/DNA%20supercoil
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DNA supercoiling refers to the amount of twist in a particular DNA strand, which determines the amount of strain on it. A given strand may be "positively supercoiled" or "negatively supercoiled" (more or less tightly wound). The amount of a strand’s supercoiling affects a number of biological processes, such as compacting DNA and regulating access to the genetic code (which strongly affects DNA metabolism and possibly gene expression). Certain enzymes, such as topoisomerases, change the amount of DNA supercoiling to facilitate functions such as DNA replication and transcription. The amount of supercoiling in a given strand is described by a mathematical formula that compares it to a reference state known as "relaxed B-form" DNA.
Overview
In a "relaxed" double-helical segment of B-DNA, the two strands twist around the helical axis once every 10.4–10.5 base pairs of sequence. Adding or subtracting twists, as some enzymes do, imposes strain. If a DNA segment under twist strain is closed into a circle by joining its two ends, and then allowed to move freely, it takes on different shape, such as a figure-eight. This shape is referred to as a supercoil. (The noun form "supercoil" is often used when describing DNA topology.)
The DNA of most organisms is usually negatively supercoiled. It becomes temporarily positively supercoiled when it is being replicated or transcribed. These processes are inhibited (regulated) if it is not promptly relaxed. The simplest shape of a supercoil is a figure eight; a circular DNA strand assumes this shape to accommodate more or few helical twists. The two lobes of the figure eight will appear rotated either clockwise or counterclockwise with respect to one another, depending on whether the helix is over- or underwound. For each additional helical twist being accommodated, the lobes will show one more rotation about their axis.
Lobal contortions of a circular DNA, such as the rotation of the figure-eight lobes above, are referred to as
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https://en.wikipedia.org/wiki/Bone%20decalcification
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Bone decalcification is the softening of bones due to the removal of calcium ions, and can be performed as a histological technique to study bones and extract DNA. This process also occurs naturally during bone development and growth, and when uninhibited, can cause diseases such as osteomalacia.
Histology
Since calcium-rich bones are exceedingly difficult to study, scientists use bone decalcification to make specimens available for their research. For example, bone decalcification has been used to examine cartilage and magnesium levels in order to understand bone decay. There are two categories of decalcifying agents for removing calcium ions: chelating agents and acids. The acids are further divided into weak (picric, acetic and formic acid) and strong acids (nitric and hydrochloric acid). The acids help produce a solution of calcium ions while the chelating agents take up the calcium ions. The most frequently used chelating agent is Ethylenediaminetetraacetic acid (EDTA). Decalcification is a lengthy procedure, as bone pieces have to be left in the decalcifying agent for days to weeks, depending on the size of the bone. There are numerous methods to test when bone decalcification is complete, such as X-ray examination, chemical analysis, and measurement of specimen flexibility. Decalcification is necessary to obtain soft sections of the bone using a microtome. Every thin section of the bone that is cut can be processed (see tissue processing) like any other soft tissue of the body.
See also
Bone seeker
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https://en.wikipedia.org/wiki/Atlantic%20meridional%20overturning%20circulation
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The Atlantic meridional overturning circulation (AMOC) is part of a global thermohaline circulation in the oceans and is the zonally integrated component of surface and deep currents in the Atlantic Ocean. It is characterized by a northward flow of warm, salty water in the upper layers of the Atlantic, and a southward flow of colder, deep waters. These "limbs" are linked by regions of overturning in the Nordic and Labrador Seas and the Southern Ocean, although the extent of overturning in the Labrador Sea is disputed. The AMOC is an important component of the Earth's climate system, and is a result of both atmospheric and thermohaline drivers.
Climate change has the potential to weaken the AMOC through increases in ocean heat content and elevated freshwater flows from the melting ice sheets. Oceanographic reconstructions generally suggest that the AMOC is already weaker than it was before the Industrial Revolution, although there is a robust debate over the role of climate change versus the circulation's century-scale and millennial-scale variability. Climate models consistently project that the AMOC would weaken further over the 21st century, which would affect average temperature over areas like Scandinavia and Britain that are warmed by the North Atlantic drift, as well as accelerate sea level rise around North America and reduce primary production in the North Atlantic.
Severe weakening of the AMOC has the potential to cause an outright collapse of the circulation, which would not be easily reversible and thus constitute one of the tipping points in the climate system. A shutdown would have far greater impacts than a slowdown on both the marine and some terrestrial ecosystems: it would lower the average temperature and precipitation in Europe, slashing the region's agricultural output, and may have a substantial effect on extreme weather events. Earth system models used in Coupled Model Intercomparison Project indicate that shutdown is only likely after high l
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https://en.wikipedia.org/wiki/Contact%20process%20%28mathematics%29
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The contact process is a stochastic process used to model population growth on the set of sites of a graph in which occupied sites become vacant at a constant rate, while vacant sites become occupied at a rate proportional to the number of occupied neighboring sites. Therefore, if we denote by the proportionality constant, each site remains occupied for a random time period which is exponentially distributed parameter 1 and places descendants at every vacant neighboring site at times of events of a Poisson process parameter during this period. All processes are independent of one another and of the random period of time sites remains occupied.
The contact process can also be interpreted as a model for the spread of an infection by
thinking of particles as a bacterium spreading over individuals that are positioned at the sites of , occupied sites correspond to infected individuals, whereas vacant correspond to healthy ones.
The main quantity of interest is the number of particles in the process, say , in the first interpretation, which corresponds to the number of infected sites in the second one. Therefore, the process survives whenever the number of particles is positive for all times, which corresponds to the case that there are always infected individuals in the second one. For any infinite graph there exists a positive and finite critical value so that if then survival of the process starting from a finite number of particles occurs with positive probability, while if their extinction is almost certain. Note that by and the infinite monkey theorem, survival of the process is equivalent to , as , whereas extinction is equivalent to , as , and therefore, it is natural to ask about the rate at which when the process survives.
Mathematical definition
If the state of the process at time is , then a site in is occupied, say by a particle, if and vacant if .
The contact process is a continuous-time Markov process with state space , where is a fi
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https://en.wikipedia.org/wiki/Tensor%20product%20network
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A tensor product network, in artificial neural networks, is a network that exploits the properties of tensors to model associative concepts such as variable assignment. Orthonormal vectors are chosen to model the ideas (such as variable names and target assignments), and the tensor product of these vectors construct a network whose mathematical properties allow the user to easily extract the association from it.
See also
Neural network
Artificial neural networks
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https://en.wikipedia.org/wiki/Orthogonality%20%28term%20rewriting%29
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Orthogonality as a property of term rewriting systems (TRSs) describes where the reduction rules of the system are all left-linear, that is each variable occurs only once on the left hand side of each reduction rule, and there is no overlap between them, i.e. the TRS has no critical pairs. For example is not left-linear.
Orthogonal TRSs have the consequent property that all reducible expressions (redexes) within a term are completely disjoint -- that is, the redexes share no common function symbol.
For example, the TRS with reduction rules
is orthogonal -- it is easy to observe that each reduction rule is left-linear, and the left hand side of each reduction rule shares no function symbol in common, so there is no overlap.
Orthogonal TRSs are confluent.
Weak orthogonality
A TRS is weakly orthogonal if it is left-linear and contains only trivial critical pairs, i.e. if is a critical pair then . Weakly orthogonal TRSs are confluent.
A TRS is almost orthogonal if it is weakly orthogonal and has the additional property that overlap between redex occurrences occurs only at the root of the redex occurrences.
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https://en.wikipedia.org/wiki/Space%20toilet
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A space toilet or zero-gravity toilet is a toilet that can be used in a weightless environment. In the absence of weight, the collection and retention of liquid and solid waste is directed by use of airflow. Since the air used to direct the waste is returned to the cabin, it is filtered beforehand to control odor and cleanse bacteria. In older systems, wastewater is vented into space, and any solids are compressed and stored for removal upon landing. More modern systems expose solid waste to vacuum pressures to kill bacteria, which prevents odor problems and kills pathogens.
Background
Astronauts say that they are most often asked how they go to the bathroom in space. In space, weightlessness causes fluids to distribute uniformly around human bodies. Kidneys detect the fluid movement and a physiological reaction causes the humans to need to relieve themselves within two hours of departure from Earth. The space toilet was thus the first device activated on shuttle flights, after astronauts unbuckled themselves.
Mechanism
In the absence of gravity, space toilets use air flow to pull urine and feces away from the body and into the proper receptacles. A new feature of the space toilet is the automatic start of air flow when the toilet lid is lifted, which also helps with odor control. By popular (astronaut) demand, it also includes a more ergonomic design requiring less clean-up and maintenance time, with corrosion-resistant, durable parts to reduce the likelihood of maintenance outside of the set schedule. Less time spent on plumbing means more time for the crew to spend on science and other high-priority exploration focused tasks.
The crew use a specially shaped funnel and hose for urine and the seat for bowel movements. The funnel and seat can be used simultaneously, reflecting feedback from female astronauts. The space toilet seat may look uncomfortably small and pointy, but in microgravity, it is ideal. It provides ideal body contact to make sure that everythi
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https://en.wikipedia.org/wiki/List%20of%20DVD%20manufacturers
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This aims to be a complete list of DVD manufacturers.
This list may not be complete or up to date. If you see a manufacturer that should be here but isn't (or one that shouldn't be here but is), please update the page accordingly. This list is only a list of brand names for DVDs and not an actual
manufacturers list.
A
Aiwa
Akai
Alba
Amazon
Amstrad
Apex Digital
Apple
ACCURA
Acme
Acer
Allied Electronics Pte Limited
Asus
B
Bang & Olufsen
BenQ
Bose
Bush
Beyond
C
CMC Magnetics
Citizen Electronics Co., Ltd.
Craig Electronics
Curtis International Ltd.
D
Daewoo Electronics
Denon
Dell
E
Emerson
F
Facebook
Funai
Fukuda
G
GE
Google
Go Electronics
Grundig
H
Harman/kardon
Hitachi
Hewlett-Packard
I
Imation
J
Jodie
JVC
K
KDS
L
Lenovo
LG
LiteOn
Loewe
M
Magnavox
Marantz
Maxell
Medion
Memorex
Microsoft Windows
Mitsubishi Electric
Moser Baer
Mustek Systems, Inc.
N
NEC
O
Onn
Oppo
Orion Electric
P
Panasonic
Philips
Pioneer
ProScan
Pressing-Media
R
RCA
Ritek
Ricoh
S
Samsung
Sanyo
Sharp
Sony
Sylvania
Symphonic
SM Pictures
T
Teac
Technics
Technika
Thomson
Toshiba
U
V
Verbatim Corporation
W
Weltec
Y
Yamaha
Z
Zenith
See also
DVD
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https://en.wikipedia.org/wiki/Caramel%20color
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Caramel color or caramel coloring is a water-soluble food coloring. It is made by heat treatment of carbohydrates (sugars), in general in the presence of acids, alkalis, or salts, in a process called caramelization. It is more fully oxidized than caramel candy, and has an odor of burnt sugar and a somewhat bitter taste. Its color ranges from pale yellow to amber to dark brown.
Caramel color is one of the oldest and most used food colorings for enhancing naturally occurring colors, correcting natural variations in color, and replacing color that is lost to light degradation during food processing and storage. The use of caramel color as a food additive in the brewing industry in the 19th century is the first recorded instance of it being manufactured and used on a wide scale. Today, caramel color is found in many commercially made foods and beverages, including batters, beer, brown bread, buns, chocolate, cookies, cough drops, spirits and liquor such as brandy, rum, and whisky, chocolate-flavored confectionery and coatings, custards, decorations, fillings and toppings, potato chips, dessert mixes, doughnuts, fish and shellfish spreads, frozen desserts, fruit preserves, glucose tablets, gravy, ice cream, pickles, sauces and dressings, soft drinks (especially colas), sweets, vinegar, and more. Caramel color is widely approved for use in food globally but application and use level restrictions vary by country.
Production
Caramel color is manufactured by heating carbohydrates, either alone or in the presence of acids, alkalis, and/or salts. Caramel color is produced from commercially available nutritive sweeteners consisting of fructose, dextrose (glucose), invert sugar, sucrose, malt syrup, molasses, starch hydrolysates, and fractions thereof. The acids that may be used are sulfuric, sulfurous, phosphoric, acetic, and citric acids; the alkalis are ammonium, sodium, potassium, and calcium hydroxides; and the salts are ammonium, sodium, and potassium carbonate, bicarbon
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https://en.wikipedia.org/wiki/Carl%20August%20von%20Steinheil
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Carl August von Steinheil (12 October 1801 – 14 September 1870) was a German physicist, inventor, engineer and astronomer.
Biography
Steinheil was born in Ribeauvillé, Alsace. He studied law in Erlangen since 1821. He then studied astronomy in Göttingen and Königsberg. He continued his studies in astronomy and physics while living in his father's manor in Perlachseck near Munich. From 1832 to 1849, Steinheil was professor for mathematics and physics at the University of Munich.
In late 1838 or early 1839, Steinheil, along with Franz von Kobell, used silver chloride and a cardboard camera to make pictures in negative of the Frauenkirche and other Munich buildings, then taking another picture of the negative to get a positive, the actual black and white reproduction of a view on the object. The pictures produced were round with a diameter of 4 cm, the method was later named the “Steinheil method.” Several of these photographs were exhibited by Steinheil throughout April and Summer 1839. In July 1839, Steinheil demonstrated his photography method at Nymphenburg Palace in the presence of Queen Therese.
Steinheil was also one of the first to use the daguerreotype in Germany. By December 1839, he made the first portable metal camera in the world. It was nineteen times smaller than the camera sold by Daguerre. At least ten of these cameras were manufactured.
In 1846, Steinheil travelled to Naples to install a new system for weight and measure units. Three years later, he was appointed to the Board of Telegraphy of the Austrian Trade Ministry. Steinheil was tasked with designing a telegraph network for the entire empire, and helped to form the Deutsch-Österreichischer Telegraphenverein (German-Austrian Telegraph Society).
In 1851, he started the Swiss telegraph network. Steinheil returned Munich as konservator (curator) of the mathematical-physical collections and ministerial secretary in the Trade Ministry of Bavaria.
In 1854, he founded C. A. Steinheil & Söhne, an
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https://en.wikipedia.org/wiki/Formylation
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Formylation refers to any chemical processes in which a compound is functionalized with a formyl group (-CH=O). In organic chemistry, the term is most commonly used with regards to aromatic compounds (for example the conversion of benzene to benzaldehyde in the Gattermann–Koch reaction). In biochemistry the reaction is catalysed by enzymes such as formyltransferases.
Formylation generally involves the use of formylation agents, reagents that give rise to the CHO group. Among the many formylation reagents, particularly important are formic acid and carbon monoxide. A formylation reaction in organic chemistry refers to organic reactions in which an organic compound is functionalized with a formyl group (-CH=O). The reaction is a route to aldehydes (C-CH=O), formamides (N-CH=O), and formate esters (O-CH=O).
Formylation agents
A reagent that delivers the formyl group is called a formylating agent.
Formic acid
Dimethylformamide and phosphorus oxychloride in the Vilsmeier-Haack reaction.
Hexamethylenetetramine in the Duff reaction and the Sommelet reaction
Carbon monoxide and hydrochloric acid in the Gattermann-Koch reaction
Cyanides in the Gattermann reaction. This method synthesizes aromatic aldehydes using hydrogen chloride and hydrogen cyanide (or another metallic cyanide as such zinc cyanide) in the presence of Lewis acid catalysts:
Chloroform in the Reimer-Tiemann reaction
Dichloromethyl methyl ether in Rieche formylation
A particularly important formylation process is hydroformylation, which converts alkenes to the homologated aldehyde.
Aromatic formylation
Formylation reactions are a form of electrophilic aromatic substitution and therefore work best when the aromatic starting materials are electron-rich. Phenols are very commonly encountered as they can be readily deprotonated to form phenoxides which are excellent nucleophiles, other electron rich substrates such as mesitylene, pyrrole, or fused aromatic rings can also be expected to react. Benzene w
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https://en.wikipedia.org/wiki/Windows%20DNA
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Windows DNA, short for Windows Distributed interNet Applications Architecture, is a marketing name for a collection of Microsoft technologies that enable the Windows platform and the Internet to work together. Some of the principal technologies that DNA comprises are ActiveX, Dynamic HTML (DHTML) and COM. Windows DNA has been largely superseded by the Microsoft .NET Framework, and Microsoft no longer uses the term. To support web-based applications, Microsoft has tried to add Internet features into the operating system using COM. However, developing a web-based application using COM-based Windows DNA is quite complex, because Windows DNA requires the use of numerous technologies and languages.
These technologies are completely unrelated from a syntactic point of view.
External links
Unraveling Windows DNA at MSDN
Windows DNA at Smart Computing Encyclopedia
Microsoft's DNA Web page in 1999
Windows communication and services
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https://en.wikipedia.org/wiki/Device%20under%20test
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A device under test (DUT), also known as equipment under test (EUT) and unit under test (UUT), is a manufactured product undergoing testing, either at first manufacture or later during its life cycle as part of ongoing functional testing and calibration checks. This can include a test after repair to establish that the product is performing in accordance with the original product specification.
Electronics testing
In the electronics industry a DUT is any electronic assembly under test. For example, cell phones coming off of an assembly line may be given a final test in the same way as the individual chips were earlier tested. Each cell phone under test is, briefly, the DUT.
For circuit boards, the DUT is often connected to the test equipment using a bed of nails tester of pogo pins.
Semiconductor testing
In semiconductor testing, the device under test is a die on a wafer or the resulting packaged part. A connection system is used, connecting the part to automatic or manual test equipment. The test equipment then applies power to the part, supplies stimulus signals, then measures and evaluates the resulting outputs from the device. In this way, the tester determines whether the particular device under test meets the device specifications.
While packaged as a wafer, automatic test equipment (ATE) can connect to the individual units using a set of microscopic needles. Once the chips are sawn apart and packaged, test equipment can connect to the chips using ZIF sockets (sometimes called contactors).
See also
Automatic test equipment
DUT board
Product testing
System under test
Test bench
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https://en.wikipedia.org/wiki/Drinker%20paradox
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The drinker paradox (also known as the drinker's theorem, the drinker's principle, or the drinking principle) is a theorem of classical predicate logic that can be stated as "There is someone in the pub such that, if he or she is drinking, then everyone in the pub is drinking." It was popularised by the mathematical logician Raymond Smullyan, who called it the "drinking principle" in his 1978 book What Is the Name of this Book?
The apparently paradoxical nature of the statement comes from the way it is usually stated in natural language. It seems counterintuitive both that there could be a person who is causing the others to drink, or that there could be a person such that all through the night that one person were always the last to drink. The first objection comes from confusing formal "if then" statements with causation (see Correlation does not imply causation or Relevance logic for logics that demand relevant relationships between premise and consequent, unlike classical logic assumed here). The formal statement of the theorem is timeless, eliminating the second objection because the person the statement holds true for at one instant is not necessarily the same person it holds true for at any other instant.
The formal statement of the theorem is
where D is an arbitrary predicate and P is an arbitrary nonempty set.
Proofs
The proof begins by recognizing it is true that either everyone in the pub is drinking, or at least one person in the pub is not drinking. Consequently, there are two cases to consider:
Suppose everyone is drinking. For any particular person, it cannot be wrong to say that if that particular person is drinking, then everyone in the pub is drinking—because everyone is drinking. Because everyone is drinking, then that one person must drink because when that person drinks everybody drinks, everybody includes that person.
Otherwise at least one person is not drinking. For any nondrinking person, the statement if that particular person is dr
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https://en.wikipedia.org/wiki/Positioning%20system
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A positioning system is a system for determining the position of an object in space. One of the most well-known and commonly used positioning systems is the Global Positioning System (GPS).
Positioning system technologies exist ranging from worldwide coverage with meter accuracy to workspace coverage with sub-millimeter accuracy.
Coverage
Interplanetary systems
Interplanetary-radio communication systems not only communicate with spacecraft, but they are also used to determine their position. Radar can track targets near the Earth, but spacecraft in deep space must have a working transponder on board to echo a radio signal back. Orientation information can be obtained using star trackers.
Global systems
Global navigation satellite systems (GNSS) allow specialized radio receivers to determine their 3-D space position, as well as time, with an accuracy of 2–20 metres or tens of nanoseconds. Currently deployed systems use microwave signals that can only be received reliably outdoors and that cover most of Earth's surface, as well as near-Earth space.
The existing and planned systems are:
Global Positioning System – US military system, fully operational since 1995
GLONASS – Russian military system, fully operational since October 2011
Galileo – European Community, fully operational since December 2019
Beidou navigation system – China, fully operational since June 2020
Indian Regional Navigation Satellite System – a planned project in India
Regional systems
Networks of land-based positioning transmitters allow specialized radio receivers to determine their 2-D position on the surface of the Earth. They are generally less accurate than GNSS because their signals are not entirely restricted to line-of-sight propagation, and they have only regional coverage. However, they remain useful for special purposes and as a backup where their signals are more reliably received, including underground and indoors, and receivers can be built that consume very low battery powe
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https://en.wikipedia.org/wiki/Overlap%20%28term%20rewriting%29
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In mathematics, computer science and logic, overlap, as a property of the reduction rules in term rewriting system, describes a situation where a number of different reduction rules specify potentially contradictory ways of reducing a reducible expression, also known as a redex, within a term.
More precisely, if a number of different reduction rules share function symbols on the left-hand side, overlap can occur. Often we do not consider trivial overlap with a redex and itself.
Examples
Consider the term rewriting system defined by the following reduction rules:
The term can be reduced via ρ1 to yield , but it can also be reduced via ρ2 to yield . Note how the redex is contained in the redex . The result of reducing different redexes is described in a what is known as a critical pair; the critical pair arising out of this term rewriting system is .
Overlap may occur with fewer than two reduction rules.
Consider the term rewriting system defined by the following reduction rule:
The term has overlapping redexes, which can be either applied to the innermost occurrence or to the outermost occurrence of the term.
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https://en.wikipedia.org/wiki/Darwin%20%28unit%29
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The darwin (d) is a unit of evolutionary change, defined by J. B. S. Haldane in 1949. One darwin is defined to be an e-fold (about 2.718) change in a trait over one million years. Haldane named the unit after Charles Darwin.
Equation
The equation for calculating evolutionary change in darwins () is:
where and are the initial and final values of the trait and is the change in time in millions of years. An alternative form of this equation is:
Since the difference between two natural logarithms is a dimensionless ratio, the trait may be measured in any unit. Inexplicably, Haldane defined the millidarwin as 10−9 darwins, despite the fact that the prefix milli- usually denotes a factor of one thousandth (10−3).
Application
The measure is most useful in palaeontology, where macroevolutionary changes in the dimensions of fossils can be compared. Where this is used it is an indirect measure as it relies on phenotypic rather than genotypic data. Several data points are required to overcome natural variation within a population. The darwin only measures the evolution of a particular trait rather than a lineage; different traits may evolve at different rates within a lineage. The evolution of traits can however be used to infer as a proxy the evolution of lineages.
See also
Evolutionary biology
Macroevolution
Microevolution
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https://en.wikipedia.org/wiki/Spam%20Cube
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Spam Cube, Inc was a high-tech startup company based in the midtown area of New York City. The company invented and manufactured the Spam Cube, a SaaS (Security As A Service) network security hardware device for consumers that blocked spam e-mail, computer viruses and phishing. The company invented a SaaS delivery platform technology that enables any home networking embedded device such as a Broadband cable modem, DSL modem, Wireless router or Femtocell to offer network Security As A Service technology that blocks spam e-mail, computer viruses and phishing. The Spam Cube SaaS platform gave the consumer the choice to select spam e-mail, computer viruses, and phishing blocking technology that was powered by either McAfee or Symantec managed enterprise Security As A Service technology.
Trademark Issues
In May 2006, the company ran into a costly legal battle with Hormel Foods over its trademark "Spam Cube". Hormel Foods claimed that the company's "Spam Cube" brand name was causing confusion amongst consumers and that consumers were not able to tell the difference between the Spam Cube, a cube-shaped home network security device, and Hormel's cube-shaped SPAM canned meat product. In February 2008, the company won the legal battle against Hormel Foods in the United States. The SPAM trademark dispute was widely publicized since the dispute would have forced the company into bankruptcy had Hormel Foods won.
Competitors
Three years after Spam Cube released its technology, Cisco Systems teamed up with Trend Micro to manufacture the Linksys Home Network Defender. Linksys and Trend Micro competed directly with Spam Cube for market share in the embedded device SaaS market.
See also
Anti-spam appliances
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https://en.wikipedia.org/wiki/CPU%20multiplier
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In computing, the clock multiplier (or CPU multiplier or bus/core ratio) sets the ratio of an internal CPU clock rate to the externally supplied clock. A CPU with a 10x multiplier will thus see 10 internal cycles (produced by PLL-based frequency multiplier circuitry) for every external clock cycle. For example, a system with an external clock of 100 MHz and a 36x clock multiplier will have an internal CPU clock of 3.6 GHz. The external address and data buses of the CPU (often collectively termed front side bus (FSB) in PC contexts) also use the external clock as a fundamental timing base; however, they could also employ a (small) multiple of this base frequency (typically two or four) to transfer data faster.
The internal frequency of microprocessors is usually based on FSB frequency. To calculate internal frequency the CPU multiplies bus frequency by a number called the clock multiplier. For calculation, the CPU uses actual bus frequency, and not effective bus frequency. To determine the actual bus frequency for processors that use dual-data rate (DDR) buses (AMD Athlon and Duron) and quad-data rate buses (all Intel microprocessors starting from Pentium 4) the effective bus speed should be divided by 2 for AMD or 4 for Intel.
Clock multipliers on many modern processors are fixed; it is usually not possible to change them. Some versions of processors have clock multipliers unlocked; that is, they can be "overclocked" by increasing the clock multiplier setting in the motherboard's BIOS setup program. Some CPU engineering samples may also have the clock multiplier unlocked. Many Intel qualification samples have maximum clock multiplier locked: these CPUs may be underclocked (run at lower frequency), but they cannot be overclocked by increasing clock multiplier higher than intended by CPU design. While these qualification samples and majority of production microprocessors cannot be overclocked by increasing their clock multiplier, they still can be overclocked by
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https://en.wikipedia.org/wiki/Simon%20%28cat%29
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Simon (c. 1947 – 28 November 1949) was a ship's cat who served on the Royal Navy sloop-of-war HMS Amethyst. In 1949, during the Yangtze Incident, he received the PDSA's Dickin Medal after surviving injuries from an artillery shell, raising morale, and killing off a rat infestation during his service.
Origin
Simon was found wandering the dockyards of Hong Kong in March 1948 by 17-year-old Ordinary seaman George Hickinbottom, a member of the crew of the British frigate HMS Amethyst stationed in the city in the late 1940s. At this stage, it is thought Simon was approximately a year old, and was very undernourished and unwell. Hickinbottom smuggled the cat aboard ship, and Simon soon ingratiated himself with the crew and officers, particularly because he was adept at catching and killing rats on the lower decks. Simon rapidly gained a reputation for cheekiness, leaving presents of dead rats in sailors' beds, and sleeping in the captain's cap.
The crew viewed Simon as a lucky mascot, and when the ship's commander changed later in 1948, the outgoing Ian Griffiths left the cat for his successor, Lieutenant Commander Bernard Skinner, who took an immediate liking to the friendly animal. However, Skinner's first mission in command of the Amethyst was to travel up the Yangtze River to Nanjing to replace the duty ship there, HMS Consort. Halfway up the river the ship became embroiled in the Amethyst Incident, when a Chinese PLA field gun battery opened fire on the frigate. One of the first rounds tore through the captain's cabin, seriously wounding Simon. Lieutenant Commander Skinner died of his wounds soon after the attack.
Recovery
The badly wounded cat crawled on deck, and was rushed to the medical bay, where the ship's surviving medical staff cleaned his burns, and removed four pieces of shrapnel, but he was not expected to last the night. He managed to survive, however, and after a period of recovery, returned to his former duties in spite of the indifference he faced f
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https://en.wikipedia.org/wiki/Outline%20of%20computer%20vision
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The following outline is provided as an overview of and topical guide to computer vision:
Computer vision – interdisciplinary field that deals with how computers can be made to gain high-level understanding from digital images or videos. From the perspective of engineering, it seeks to automate tasks that the human visual system can do. Computer vision tasks include methods for acquiring digital images (through image sensors), image processing, and image analysis, to reach an understanding of digital images. In general, it deals with the extraction of high-dimensional data from the real world in order to produce numerical or symbolic information that the computer can interpret. The image data can take many forms, such as video sequences, views from multiple cameras, or multi-dimensional data from a medical scanner. As a technological discipline, computer vision seeks to apply its theories and models for the construction of computer vision systems. As a scientific discipline, computer vision is concerned with the theory behind artificial systems that extract information from images.
Branches of computer vision
Computer stereo vision
Underwater computer vision
History of computer vision
History of computer vision
Computer vision subsystems
Image enhancement
Image denoising
Image histogram
Inpainting
Super-resolution imaging
Histogram equalization
Tone mapping
Retinex
Gamma correction
Anisotropic diffusion (Perona–Malik equation)
Transformations
Affine transform
Homography (computer vision)
Hough transform
Radon transform
Walsh–Hadamard transform
Filtering, Fourier and wavelet transforms and image compression
Image compression
Filter bank
Gabor filter
JPEG 2000
Adaptive filtering
Color vision
Visual perception
Human visual system model
Color matching function
Color space
Color appearance model
Color management system
Color mapping
Color model
Color profile
Feature extraction
Active contour
Blob detection
Canny edge det
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https://en.wikipedia.org/wiki/Design%20Criteria%20Standard%20for%20Electronic%20Records%20Management%20Software%20Applications
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United States Department of Defense standard 5015.2-STD, the Design Criteria Standard for Electronic Records Management Software Applications, was implemented in June 2002. This standard defines requirements for the management of records within the Department of Defense, which has become the accepted standard for many state, county, and local governments.
The standard was developed in 1996 by a team led by Kenneth Thibodeau of the National Archives and Records Administration.
, only three companies are certified for records management at all levels for the Department of Defense: HP Enterprise (American), Feith Systems and Software (American), and Open Text (Canadian).
The following additional companies have some level of certification: IBM Corporation, Oracle USA, Gimmal LLC, EMC, Newgen Software, ZL Technologies, Perceptive, Laserfiche, Alfresco, Collabware, and Northrop Grumman.
See also
Records management
Digital curation
Archives
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https://en.wikipedia.org/wiki/Mechanism%20of%20action
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In pharmacology, the term mechanism of action (MOA) refers to the specific biochemical interaction through which a drug substance produces its pharmacological effect. A mechanism of action usually includes mention of the specific molecular targets to which the drug binds, such as an enzyme or receptor. Receptor sites have specific affinities for drugs based on the chemical structure of the drug, as well as the specific action that occurs there.
Drugs that do not bind to receptors produce their corresponding therapeutic effect by simply interacting with chemical or physical properties in the body. Common examples of drugs that work in this way are antacids and laxatives.
In contrast, a mode of action (MoA) describes functional or anatomical changes, at the cellular level, resulting from the exposure of a living organism to a substance.
Importance
Elucidating the mechanism of action of novel drugs and medications is important for several reasons:
In the case of anti-infective drug development, the information permits anticipation of problems relating to clinical safety. Drugs disrupting the cytoplasmic membrane or electron transport chain, for example, are more likely to cause toxicity problems than those targeting components of the cell wall (peptidoglycan or β-glucans) or 70S ribosome, structures which are absent in human cells.
By knowing the interaction between a certain site of a drug and a receptor, other drugs can be formulated in a way that replicates this interaction, thus producing the same therapeutic effects. Indeed, this method is used to create new drugs.
It can help identify which patients are most likely to respond to treatment. Because the breast cancer medication trastuzumab is known to target protein HER2, for example, tumors can be screened for the presence of this molecule to determine whether or not the patient will benefit from trastuzumab therapy.
It can enable better dosing because the drug's effects on the target pathway can be m
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https://en.wikipedia.org/wiki/Actinides%20in%20the%20environment
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Environmental radioactivity is not limited to actinides; non-actinides such as radon and radium are of note. While all actinides are radioactive, there are a lot of actinides or actinide-relating minerals in the Earth's crust such as uranium and thorium. These minerals are helpful in many ways, such as carbon-dating, most detectors, X-rays, and more.
Inhalation versus ingestion
Generally, ingested insoluble actinide compounds, such as high-fired uranium dioxide and mixed oxide (MOX) fuel, will pass through the digestive system with little effect since they cannot dissolve and be absorbed by the body. Inhaled actinide compounds, however, will be more damaging as they remain in the lungs and irradiate the lung tissue.
Ingested low-fired oxides and soluble salts such as nitrate can be absorbed into the blood stream. If they are inhaled then it is possible for the solid to dissolve and leave the lungs. Hence, the dose to the lungs will be lower for the soluble form.
Actinium
Actinium can be naturally found in traces in uranium ore as 227Ac, an α and β emitter with half-life 21.773 years. Uranium ore contains about 0.2 mg of actinium per ton of uranium. It is more commonly made in milligram amounts by neutron irradiation of 226Ra in a nuclear reactor. Natural actinium almost exclusively consists of one isotope, 227Ac, with only minute traces of other shorter-lived isotopes (225Ac and 228Ac) occurring in other decay chains.
Thorium
In India, a large amount of thorium ore can be found in the form of monazite in placer deposits of the Western and Eastern coastal dune sands, particularly in the Tamil Nadu coastal areas. The residents of this area are exposed to a naturally occurring radiation dose ten times higher than the worldwide average.
Occurrence
Thorium is found at low levels in most rocks and soils, where it is about three times more abundant than uranium and about as abundant as lead. On average, soil commonly contains approximately 6 parts per million (ppm
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https://en.wikipedia.org/wiki/Metatheorem
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In logic, a metatheorem is a statement about a formal system proven in a metalanguage. Unlike theorems proved within a given formal system, a metatheorem is proved within a metatheory, and may reference concepts that are present in the metatheory but not the object theory.
A formal system is determined by a formal language and a deductive system (axioms and rules of inference). The formal system can be used to prove particular sentences of the formal language with that system. Metatheorems, however, are proved externally to the system in question, in its metatheory. Common metatheories used in logic are set theory (especially in model theory) and primitive recursive arithmetic (especially in proof theory). Rather than demonstrating particular sentences to be provable, metatheorems may show that each of a broad class of sentences can be proved, or show that certain sentences cannot be proved.
Examples
Examples of metatheorems include:
The deduction theorem for first-order logic says that a sentence of the form φ→ψ is provable from a set of axioms A if and only if the sentence ψ is provable from the system whose axioms consist of φ and all the axioms of A.
The class existence theorem of von Neumann–Bernays–Gödel set theory states that for every formula whose quantifiers range only over sets, there is a class consisting of the sets satisfying the formula.
Consistency proofs of systems such as Peano arithmetic.
See also
Metamathematics
Use–mention distinction
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https://en.wikipedia.org/wiki/Manure-derived%20synthetic%20crude%20oil
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Manure-derived synthetic crude oil is a synthetic bio-oil chemically engineered (converted) from animal or human manure. Research into the production of manure-derived synthetic fuel began with pig manure in 1996 at the University of Illinois at Urbana–Champaign by the research team led by professors Yuanhui Zhang and Lance Schideman. They developed a method for converting raw pig manure into bio-oil through thermal depolymerization (thermochemical conversion). This process uses a thermochemical conversion reactor to apply heat and pressure for breaking down carbohydrate materials. As a result, bio-oil, methane and carbon dioxide are produced.
With further research, large-scale chemical processing in a refinery-style environment could help process millions of gallons of "pig biocrude" per day. However, this technology is still in its infancy and could produce only of oil per of manure. In 2006, preparations for a construction of a pilot plant started. It is developed by Snapshot Energy, a start-up firm.
According to the tests conducted by the National Institute of Standards and Technology pig manure biocrude produced by current technology contains 15% water, sulfur and char waste containing heavy metals, which should be removed to improve the quality of oil.
See also
Alternative fuels
Energy and the environment
Poultry litter
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https://en.wikipedia.org/wiki/Lamella%20%28cell%20biology%29
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A lamella (: lamellae) in biology refers to a thin layer, membrane or plate of tissue. This is a very broad definition, and can refer to many different structures. Any thin layer of organic tissue can be called a lamella and there is a wide array of functions an individual layer can serve. For example, an intercellular lipid lamella is formed when lamellar disks fuse to form a lamellar sheet. It is believed that these disks are formed from vesicles, giving the lamellar sheet a lipid bilayer that plays a role in water diffusion.
Another instance of cellular lamellae can be seen in chloroplasts. Thylakoid membranes are actually a system of lamellar membranes working together, and are differentiated into different lamellar domains. This lamellar system allows plants to convert light energy into chemical energy. Chloroplasts are characterized by a system of membranes embedded in a hydrophobic proteinaceous matrix, or stroma. The basic unit of the membrane system is a flattened single vesicle called the thylakoid; thylakoids stack into grana. All the thylakoids of a granum are connected with each other, and the grana are connected by intergranal lamellae.
It is placed between the two primary cell walls of two plant cells and made up of intracellular matrix. The lamella comprises a mixture of polygalacturons (D-galacturonic acid) and neutral carbohydrates. It is soluble in the pectinase enzyme.
Lamella, in cell biology, is also used to describe the leading edge of a motile cell, of which the lamellipodia is the most forward portion.
The lipid bilayer core of biological membranes is also called lamellar phase. Thus, each bilayer of multilamellar liposomes and wall of a unilamellar liposome is also referred to as a lamella.
See also
Middle lamella
Thylakoid
Lipid bilayer
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https://en.wikipedia.org/wiki/Immunocytochemistry
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Immunocytochemistry (ICC) is a common laboratory technique that is used to anatomically visualize the localization of a specific protein or antigen in cells by use of a specific primary antibody that binds to it. The primary antibody allows visualization of the protein under a fluorescence microscope when it is bound by a secondary antibody that has a conjugated fluorophore. ICC allows researchers to evaluate whether or not cells in a particular sample express the antigen in question. In cases where an immunopositive signal is found, ICC also allows researchers to determine which sub-cellular compartments are expressing the antigen.
Immunocytochemistry vs. immunohistochemistry
Immunocytochemistry differs from immunohistochemistry in that the former is performed on samples of intact cells that have had most, if not all, of their surrounding extracellular matrix removed. This includes individual cells that have been isolated from a block of solid tissue, cells grown within a culture, cells deposited from suspension, or cells taken from a smear. In contrast, immunohistochemical samples are sections of biological tissue, where each cell is surrounded by tissue architecture and other cells normally found in the intact tissue.
Immunocytochemistry is a technique used to assess the presence of a specific protein or antigen in cells (cultured cells, cell suspensions) by use of a specific antibody, which binds to it, thereby allowing visualization and examination under a microscope. It is a valuable tool for the determination of cellular contents from individual cells. Samples that can be analyzed include blood smears, aspirates, swabs, cultured cells, and cell suspensions.
There are many ways to prepare cell samples for immunocytochemical analysis. Each method has its own strengths and unique characteristics so the right method can be chosen for the desired sample and outcome.
Cells to be stained can be attached to a solid support to allow easy handling in subsequent proc
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https://en.wikipedia.org/wiki/Terminating%20Reliable%20Broadcast
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Terminating Reliable Broadcast (TRB) is a problem in distributed computing that encapsulates the task of broadcasting a message to a set of receiving processes in the presence of faults. In particular, the sender and any other process might fail ("crash") at any time.
Problem description
A TRB protocol typically organizes the system into a sending process and a set of receiving processes, which may include the sender itself. A process is called "correct" if it does not fail at any point during its execution. The goal of the protocol is to transfer data (the "message") from the sender to the set of receiving processes. A process may perform many I/O operations during protocol execution, but eventually "delivers" a message by passing it to the application on that process that invoked the TRB protocol.
The protocol must provide important guarantees to the receiving processes. All correct receiving processes, for example, must deliver the sender's message if the sender is also correct. A receiving process may deliver a special message, ("sender faulty"), if the sender failed, but either all correct processes will deliver or none will. A correct process is therefore guaranteed that data delivered to it was also delivered to all other correct processes.
More precisely, a TRB protocol must satisfy the four formal properties below.
Termination: every correct process delivers some value.
Validity: if the sender is correct and broadcasts a message , then every correct process delivers .
Integrity: a process delivers a message at most once, and if it delivers some message , then was broadcast by the sender.
Agreement: if a correct process delivers a message , then all correct processes deliver .
The presence of faults in the system makes these properties more difficult to satisfy. A simple but invalid TRB protocol might have the sender broadcast the message to all processes, and have receiving processes deliver the message as soon as it is received. This protocol,
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https://en.wikipedia.org/wiki/Camera%20interface
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The Camera Interface block or CAMIF is the hardware block that interfaces with different image sensor interfaces and provides a standard output that can be used for subsequent image processing.
A typical Camera Interface would support at least a parallel interface although these days many camera interfaces are beginning to support the Mobile Industry Processor Interface (MIPI) Camera Serial Interface (CSI) interface.
Electrical connections
The camera interface's parallel interface consists of the following lines:
8 to 12 bits parallel data line
These are parallel data lines that carry pixel data. The data transmitted on these lines change with every Pixel Clock (PCLK).
Horizontal Sync (HSYNC)
This is a special signal that goes from the camera sensor or ISP to the camera interface. An HSYNC indicates that one line of the frame is transmitted.
Vertical Sync (VSYNC)
This signal is transmitted after the entire frame is transferred. This signal is often a way to indicate that one entire frame is transmitted.
Pixel Clock (PCLK)
This is the pixel clock and it would change on every pixel.
NOTE: The above lines are all treated as input lines to the Camera Interface hardware.
See also
Digital camera
Digital photography
Demosaicing
Digital image processing
Camera Serial Interface (CSI)
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https://en.wikipedia.org/wiki/Chuck%20Yeager%27s%20Advanced%20Flight%20Trainer
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Chuck Yeager's Advanced Flight Trainer is an aircraft simulation computer game published by Electronic Arts in 1987. It was originally released as Chuck Yeager's Advanced Flight Simulator. Due to a legal dispute with Microsoft over the term "Flight Simulator", the game was pulled from shelves and renamed. Many copies of the original version were sold prior to this. Chuck Yeager served as technical consultant for the game, where his likeness and voice were prominently used.
The game allows a player to "test pilot" 14 different airplanes, including the Bell X-1, which Yeager had piloted to become the first man to exceed Mach 1.
The game is embellished by Yeager's laconic commentary: When the user crashes one plane, Yeager remarks "You sure bought the farm on that one", or other asides.
Aircraft
Chuck Yeager's Advanced Flight Trainer includes 11 real aircraft and three experimental aircraft designed by the developers. The fictional experimental aircraft were named after people who worked on the game.
Real aircraft
Bell X-1
Cessna 172
Douglas X-3 Stiletto
General Dynamics F-16 Fighting Falcon
Lockheed SR-71 Blackbird
McDonnell Douglas F/A-18 Hornet
North American P-51 Mustang
Piper PA-28 Cherokee
Sopwith Camel
SPAD S.XIII
Supermarine Spitfire
Experimental aircraft
Grace Industries XPG-12 Samurai
Hilleman Ltd. XRH4 MadDog
Lerner Aeronautics XNL-16 Instigator
Reception
The game was a big hit for EA, selling 100,000 copies by December 1987. In May 1988, it was awarded a "Platinum" certification from the Software Publishers Association for sales above 250,000 units. Game reviewers Hartley and Patricia Lesser complimented the game in their "The Role of Computers" column in Dragon #126 (1987), giving PC/MS-DOS version of the game 4 out of 5 stars. The Lessers reviewed the Macintosh version of the game in 1988 in Dragon #140 in "The Role of Computers" column, giving that version 4 stars as well. Compute! criticized the blocky graphics and sound, but noted that the simple g
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https://en.wikipedia.org/wiki/Heteroclinic%20cycle
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In mathematics, a heteroclinic cycle is an invariant set in the phase space of a dynamical system. It is a topological circle of equilibrium points and connecting heteroclinic orbits. If a heteroclinic cycle is asymptotically stable, approaching trajectories spend longer and longer periods of time in a neighbourhood of successive equilibria.
In generic dynamical systems heteroclinic connections are of high co-dimension, that is, they will not persist if parameters are varied.
Robust heteroclinic cycles
A robust heteroclinic cycle is one which persists under small changes in the underlying dynamical system. Robust cycles often arise in the presence of symmetry or other constraints which force the existence of invariant hyperplanes. A prototypical example of a robust heteroclinic cycle is the Guckenheimer–Holmes cycle. This cycle has also been studied in the context of rotating convection, and as three competing species in population dynamics.
See also
Heteroclinic bifurcation
Heteroclinic network
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https://en.wikipedia.org/wiki/Arthur%20Riggs%20%28geneticist%29
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Arthur Dale Riggs (August 8, 1939 – March 23, 2022) was an American geneticist who worked with Genentech to express the first artificial gene in bacteria. His work was critical to the modern biotechnology industry because it was the first use of molecular techniques in commercial production of drugs and enabled the large-scale manufacturing of protein drugs, including insulin.
He was also a major factor in the origin of epigenetics.
Riggs was a professor of biology and, in 2014, founding director of the Diabetes & Metabolism Research Institute of City of Hope National Medical Center. He was the founding dean of City of Hope's graduate school, the Irell & Manella Graduate School of Biological Sciences. He was also director emeritus of the Beckman Research Institute of City of Hope National Medical Center, which he headed from 2000 to 2007. Riggs served on the board of trustees at the Keck Graduate Institute of Applied Life Sciences. In 2006, Riggs was elected to the National Academy of Sciences.
Early life and education
Riggs was born in Modesto, California, near his family's home in Ceres, California, on August 8, 1939. After the family lost their farm during the Great Depression, they moved to San Bernardino, California, where Riggs attended San Bernardino High School. He helped his father, who managed a trailer park, to build and fix things. His mother, a nurse, gave him a chemistry set to encourage his interest in chemistry and biology.
Riggs earned his undergraduate degree in chemistry at University of California, Riverside in 1961. He conducted his doctoral thesis work at the California Institute of Technology with Herschel K. Mitchell, obtaining a Ph.D. in biochemistry in 1966.
Mammalian DNA replication
As graduate students at Caltech, he and Joel A. Huberman collaborated on work that later led to a classic paper on mammalian DNA replication, which was published in 1966. They wanted to use radioactive nucleotides to tag replicating DNA and then use
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https://en.wikipedia.org/wiki/PDZ%20domain
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The PDZ domain is a common structural domain of 80-90 amino-acids found in the signaling proteins of bacteria, yeast, plants, viruses and animals. Proteins containing PDZ domains play a key role in anchoring receptor proteins in the membrane to cytoskeletal components. Proteins with these domains help hold together and organize signaling complexes at cellular membranes. These domains play a key role in the formation and function of signal transduction complexes. PDZ domains also play a highly significant role in the anchoring of cell surface receptors (such as Cftr and FZD7) to the actin cytoskeleton via mediators like NHERF and ezrin.
PDZ is an initialism combining the first letters of the first three proteins discovered to share the domain — post synaptic density protein (PSD95), Drosophila disc large tumor suppressor (Dlg1), and zonula occludens-1 protein (zo-1). PDZ domains have previously been referred to as DHR (Dlg homologous region) or GLGF (glycine-leucine-glycine-phenylalanine) domains.
In general PDZ domains bind to a short region of the C-terminus of other specific proteins. These short regions bind to the PDZ domain by beta sheet augmentation. This means that the beta sheet in the PDZ domain is extended by the addition of a further beta strand from the tail of the binding partner protein. The C-terminal carboxylate group is bound by a nest (protein structural motif) in the PDZ domain, i.e. a PDZ-binding motif.
Origins of discovery
PDZ is an acronym derived from the names of the first proteins in which the domain was observed. Post-synaptic density protein 95 (PSD-95) is a synaptic protein found only in the brain. Drosophila disc large tumor suppressor (Dlg1) and zona occludens 1 (ZO-1) both play an important role at cell junctions and in cell signaling complexes. Since the discovery of PDZ domains more than 20 years ago, hundreds of additional PDZ domains have been identified. The first published use of the phrase “PDZ domain” was not in a paper, b
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https://en.wikipedia.org/wiki/Lockin%20effect
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In superconductivity, the Lockin effect refers to the preference of vortex phases to be positioned at certain points within cells of a crystal lattice of an organic superconductor.
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https://en.wikipedia.org/wiki/Grave%20accent
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The grave accent () ( or ) is a diacritical mark used to varying degrees in French, Dutch, Portuguese, Italian and many other western European languages, as well as for a few unusual uses in English. It is also used in other languages using the Latin alphabet, such as Mohawk and Yoruba, and with non-Latin writing systems such as the Greek and Cyrillic alphabets and the Bopomofo or Zhuyin Fuhao semi-syllabary. It has no single meaning, but can indicate pitch, stress, or other features.
For the most commonly encountered uses of the accent in the Latin and Greek alphabets, precomposed characters are available. For less-used and compound diacritics, a combining character facility is available. A free-standing version of the symbol (), commonly called a backtick, also exists and has acquired other uses.
Uses
Pitch
The grave accent first appeared in the polytonic orthography of Ancient Greek to mark a lower pitch than the high pitch of the acute accent. In modern practice, it replaces an acute accent in the last syllable of a word when that word is followed immediately by another word. The grave and circumflex have been replaced with an acute accent in the modern monotonic orthography.
The accent mark was called , the feminine form of the adjective (), meaning "heavy" or "low in pitch." This was calqued (loan-translated) into Latin as which then became the English word grave.
Stress
The grave accent marks the stressed vowels of words in Maltese, Catalan, and Italian.
A general rule in Italian is that words that end with stressed , , or must be marked with a grave accent. Words that end with stressed or may bear either an acute accent or a grave accent, depending on whether the final e or o sound is closed or open, respectively. Some examples of words with a final grave accent are ("city"), ("so/then/thus"), ("more"/"plus"), ("Moses"), and ("[he/she/it] brought/carried"). Typists who use a keyboard without accented characters and are unfamiliar with input
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https://en.wikipedia.org/wiki/Food%20biodiversity
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Food biodiversity is defined as "the diversity of plants, animals and other organisms used for food, covering the genetic resources within species, between species and provided by ecosystems."
Food biodiversity can be considered from two main perspectives: production and consumption. From a consumption perspective, food biodiversity describes the diversity of foods in human diets and their contribution to dietary diversity, cultural identity and good nutrition. Production of food biodiversity looks at the thousands of food products, such as fruits, nuts, vegetables, meat and condiments sourced from agriculture and from the wild (e.g. forests, uncultivated fields, water bodies). Food biodiversity covers the diversity between species, for example different animal and crop species, including those considered neglected and underutilized species. Food biodiversity also comprises the diversity within species, for example different varieties of fruit and vegetables, or different breeds of animals.
Food diversity, diet diversity nutritional diversity, are also terms used in the new diet culture spawned by Brandon Eisler, in the study known as Nutritional Diversity.
Consumption of food biodiversity
Food biodiversity, nutrition, and health
Promoting diversity of foods and species consumed in human diets in particular has potential co-benefits for public health as well as sustainable food systems perspective.
Food biodiversity provides necessary nutrients for quality diets and is an essential part of local food systems, cultures and food security. Promoting diversity of foods and species consumed in human diets in particular has potential co-benefits for sustainable food systems. Nutritionally, diversity in food is associated with higher micronutrient adequacy of diets. On average, per additional species consumed, mean adequacy of vitamin A, vitamin C, folate, calcium, iron, and zinc increased by 3%. From a conservation point of view, diets based on a wide variety of
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https://en.wikipedia.org/wiki/Agricultural%20chemistry
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Agricultural chemistry is the study of chemistry, especially organic chemistry and biochemistry, as they relate to agriculture. This includes agricultural production, the use of ammonia in fertilizer, pesticides, and how plant biochemistry can be used to genetically alter crops. Agricultural chemistry is not a distinct discipline, but a common thread that ties together genetics, physiology, microbiology, entomology, and numerous other sciences that impinge on agriculture.
Agricultural chemistry studies the chemical compositions and reactions involved in the production, protection, and use of crops and livestock. Its applied science and technology aspects are directed towards increasing yields and improving quality, which comes with multiple advantages and disadvantages.
Advantages and Disadvantages
The goals of agricultural chemistry are to expand understanding of the causes and effects of biochemical reactions related to plant and animal growth, to reveal opportunities for controlling those reactions, and to develop chemical products that will provide the desired assistance or control. Agricultural chemistry is therefore used in processing of raw products into foods and beverages, as well as environmental monitoring and remediation. It is also used to make feed supplements for animals, as well as medicinal compounds for the prevention or control of disease. When agriculture is considered with ecology, the sustainablility of an operation is considered.
However, modern agrochemical industry has gained a reputation for its maximising profits while violating sustainable and ecologically viable agricultural principles. Eutrophication, the prevalence of genetically modified crops and the increasing concentration of chemicals in the food chain (e.g. persistent organic pollutants) are only a few consequences of naive industrial agriculture.
Soil Chemistry
Agricultural chemistry often aims at preserving or increasing the fertility of soil, maintaining or improving the
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https://en.wikipedia.org/wiki/Chlorbenside
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Chlorbenside (C13H10Cl2S), also known as chlorparaside and chlorsulfacide, is a pesticide. It is used as an acaricide being used to kill mites and ticks.
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https://en.wikipedia.org/wiki/John%20Harnad
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John Harnad (born Hernád János) is a Hungarian-born Canadian mathematical physicist.
He did his undergraduate studies at McGill University and his doctorate at the University of Oxford (D.Phil. 1972) under the supervision of John C. Taylor. His research is on integrable systems, gauge theory and random matrices.
He is currently Director of the Mathematical Physics group at the Centre de recherches mathématiques (CRM), a national research centre in mathematics at the Université de Montréal and Professor in the Department of Mathematics and Statistics at Concordia University.
He is an affiliate member of the Perimeter Institute for Theoretical Physics
and was a long-time visiting member of the Princeton Institute for Advanced Study
.
His work has had a strong impact in several domains of mathematical physics, and his publications are very widely cited.
He has made fundamental contributions on: geometrical and topological methods in gauge theory, classical and quantum integrable systems, the spectral theory of random matrices, isomonodromic deformations, the bispectral problem, integrable random processes, transformation groups and symmetries.
In 2006, he was recipient of the CAP-CRM Prize in Theoretical and Mathematical Physics
"For his deep and lasting contributions to the theory of integrable systems with connections to gauge theory, inverse scattering and random matrices".
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https://en.wikipedia.org/wiki/International%20Day%20for%20Biological%20Diversity
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The International Day for Biological Diversity (or World Biodiversity Day) is a United Nations–sanctioned international day for the promotion of biodiversity issues. It is currently held on May 22.
The International Day for Biological Diversity falls within the scope of the UN Post-2015 Development Agenda's Sustainable Development Goals. In this larger initiative of international cooperation, the topic of biodiversity concerns stakeholders in sustainable agriculture; desertification, land degradation and drought; water and sanitation; health and sustainable development; energy; science, technology and innovation, knowledge-sharing and capacity-building; urban resilience and adaptation; sustainable transport; climate change and disaster risk reduction; oceans and seas; forests; vulnerable groups including indigenous peoples; and food security. The critical role of biodiversity in sustainable development was recognized in a Rio+20 outcome document, "The World We Want: A Future for All".
From its creation by the Second Committee of the UN General Assembly in 1993 until 2000, it was held on December 29 to celebrate the day the Convention on Biological Diversity went into effect. On December 20, 2000, the date was shifted to commemorate the adoption of the Convention on May 22, 1992, at the Rio de Janeiro Earth Summit, and partly to avoid the many other holidays that occur in late December.
Theme
See also
United Nations Decade on Biodiversity (2011–2020)
International Year of Biodiversity (2010)
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https://en.wikipedia.org/wiki/242%20%28number%29
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242 (two hundred [and] forty-two) is the natural number following 241 and preceding 243.
242 is the smallest integer to start a run of four consecutive integers with the same number of divisors.
242 is a nontotient since there is no integer with 242 coprimes below it.
242 is a palindrome.
242 is the number of parallelogram polyominoes with 8 cells.
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https://en.wikipedia.org/wiki/Goursat%27s%20lemma
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Goursat's lemma, named after the French mathematician Édouard Goursat, is an algebraic theorem about subgroups of the direct product of two groups.
It can be stated more generally in a Goursat variety (and consequently it also holds in any Maltsev variety), from which one recovers a more general version of Zassenhaus' butterfly lemma. In this form, Goursat's theorem also implies the snake lemma.
Groups
Goursat's lemma for groups can be stated as follows.
Let , be groups, and let be a subgroup of such that the two projections and are surjective (i.e., is a subdirect product of and ). Let be the kernel of and the kernel of . One can identify as a normal subgroup of , and as a normal subgroup of . Then the image of in is the graph of an isomorphism . One then obtains a bijection between :
Subgroups of which project onto both factors,
Triples with normal in , normal in and isomorphism of onto .
An immediate consequence of this is that the subdirect product of two groups can be described as a fiber product and vice versa.
Notice that if is any subgroup of (the projections and need not be surjective), then the projections from onto and are surjective. Then one can apply Goursat's lemma to .
To motivate the proof, consider the slice in , for any arbitrary . By the surjectivity of the projection map to , this has a non trivial intersection with . Then essentially, this intersection represents exactly one particular coset of . Indeed, if we have elements with and , then being a group, we get that , and hence, . It follows that and lie in the same coset of . Thus the intersection of with every "horizontal" slice isomorphic to is exactly one particular coset of in .
By an identical argument, the intersection of with every "vertical" slice isomorphic to is exactly one particular coset of in .
All the cosets of are present in the group , and by the above argument, there is an exact 1:1 correspondence between them. The proof
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https://en.wikipedia.org/wiki/Xylotheque
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A xylotheque or xylothek (from the Greek for "wood" and meaning "repository") is special form of herbarium that consists of a collection of authenticated wood specimens. It is also known as a xylarium (from the Greek for "wood" and Latin meaning "separate place"). Traditionally, xylotheque specimens were in the form of book-shaped volumes, each made of a particular kind of wood and holding samples of the different parts of the corresponding plant. While the terms are often used interchangeably, some use xylotheque to refer to these older collections of wooden 'books' and xylarium for modern collections in which some or all of the specimens are in simpler shapes, such as blocks or plaques with information engraved on their surfaces. Many countries have at least one xylotheque with native flora, and some also house flora from other parts of the world. They are valuable to specialists in forestry, botany, conservation, forensics, art restoration, paleontology, archaeology, and other fields.
History
Xylotheques date back to the later 17th century, when wood specimens began to appear in cabinets of curiosity. Over time, they grew larger and more systematic, with hundreds of individual volumes in a single collection. The oldest extant collection was established in 1823 at the University of Leningrad, and by the middle of the century they had been established in many European countries. Australia now houses 12 xylaria holding 11% of the world's wood specimens, while the Oxford Forestry Institute's xylarium holds about 13%.
In older xylotheques, the wooden volumes were typically made out of the same wood as the specimens inside and sometimes decorated with tree bark and associated lichens and mosses. Each volume housed seeds, flowers, twigs, and leaves from the corresponding tree or bush, along with a written description hidden in a small compartment set into the inner spine. An alternative form of xylotheque found in Japan and elsewhere featured paintings of the plan
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https://en.wikipedia.org/wiki/Typed%20assembly%20language
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In computer science, a typed assembly language (TAL) is an assembly language that is extended to include a method of annotating the datatype of each value that is manipulated by the code. These annotations can then be used by a program (type checker) that processes the assembly language code in order to analyse how it will behave when it is executed. Specifically, such a type checker can be used to prove the type safety of code that meets the criteria of some appropriate type system.
Typed assembly languages usually include a high-level memory management system based on garbage collection.
A typed assembly language with a suitably expressive type system can be used to enable the safe execution of untrusted code without using an intermediate representation like bytecode, allowing features similar to those currently provided by virtual machine environments like Java and .NET.
See also
Proof-carrying code
Further reading
Greg Morrisett. "Typed assembly language" in Advanced Topics in Types and Programming Languages. Editor: Benjamin C. Pierce.
External links
TALx86, a research project from Cornell University which has implemented a typed assembler for the Intel IA-32 architecture.
Assembly languages
Computer security
Programming language theory
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https://en.wikipedia.org/wiki/P/D1%20cell
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P/D1 cells are cells lining the fundus of the human stomach that produce ghrelin. Removal of these cells in gastric bypass surgery has a profound impact on later appetite regulation. These cells have also been shown to produce ghrelin's antagonistic hormone leptin. PD/1 cells are equivalent to A-like cells in rats and X-type cells in dogs. These endocrine cells can be microscopically distinguished from other gastric endocrine cells through their round, compact, electron-dense secretory granules.
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https://en.wikipedia.org/wiki/Colossale
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The musical term colossale indicates that the performer is to play the so marked passage in a fashion that suggests immensity. An example of this rare expression can be found at the climax of the huge cadenza in the first movement of Prokofiev's Second Piano Concerto in combination with the dynamic instruction fff.
Italian words and phrases
Musical notation
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https://en.wikipedia.org/wiki/Heptyl%20acetate
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Heptyl acetate (C9H18O2), also known as acetate C-7, is a colorless alcohol-soluble liquid that is the ester formed by the condensation of 1-heptanol and acetic acid.
Heptyl acetate is used as a fruit essence flavoring in foods and as a scent in perfumes. It has a woody, fruity, rumlike odor and a spicy, floral taste with a soapy, fatty texture.
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https://en.wikipedia.org/wiki/Advanced%20Mezzanine%20Card
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Advanced Mezzanine Cards are printed circuit boards (PCBs) that follow a specification of the PCI Industrial Computers Manufacturers Group (PICMG).
Known as AdvancedMC or AMC, the official specification designation is AMC.x. Originally AMC was targeted to requirements for carrier grade communications equipment, but later used in other markets.
AMC modules are designed to work standalone, hot pluggable on any carrier card (base boards and system carrier boards in AdvancedTCA Systems) or as a hot pluggable board into a backplane directly as defined by MicroTCA specifications.
The AMC standard differs from other mezzanine card standards such as PCI Mezzanine Card (PMC), PCIexpress Mezzanine Card XMC and FMC – FPGA Mezzanine Card by the 0 degree instead of 90 degree orientation of its connector enabling hot plug of the AMC.
Specifications
AMC.0 is the "base" or "core" specification. The AdvancedMC definition alone defines a protocol agnostic connector to connect to a carrier card or a backplane. Intermediate revisions are known as engineering change notices, or ECNs.
R1.0 adopted January 3, 2005
ECN-001 adopted June 2006
R2.0 adopted November 15, 2006
An AMC card can use proprietary LVDS-based signaling, or one of the following AMC specifications:
AMC.1 PCI Express (and PCI Express Advanced Switching) (ratified)
AMC.2 Gigabit Ethernet and XAUI (ratified)
AMC.3 Storage (ratified)
AMC.4 Serial RapidIO (ratified)
Sizes
There are six types of AMC cards ("Module") available. A Full-size Module is the most common, allowing up to 23.25 mm high components (from centerline of PCB). A Mid-size Module allows component heights maxed at 11.65 to 14.01 mm (depending on board location). A Compact Module allows only 8.18 mm.
AMCs used in AdvancedTCA systems
To use AMCs in ATCA-systems a special carrier card known as hybrid or cutaway carrier is required to hold one Full-size Module or two Compact-size (see connectors below). Each height is paired with a width, single or doubl
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https://en.wikipedia.org/wiki/Biocontainment
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One use of the concept of biocontainment is related to laboratory biosafety and pertains to microbiology laboratories in which the physical containment of pathogenic organisms or agents (bacteria, viruses, and toxins) is required, usually by isolation in environmentally and biologically secure cabinets or rooms, to prevent accidental infection of workers or release into the surrounding community during scientific research.
Another use of the term relates to facilities for the study of agricultural pathogens, where it is used similarly to the term "biosafety", relating to safety practices and procedures used to prevent unintended infection of plants or animals or the release of high-consequence pathogenic agents into the environment (air, soil, or water).
Terminology
The World Health Organization's 2006 publication, Biorisk management: Laboratory biosecurity guidance, defines laboratory biosafety as "the containment principles, technologies and practices that are implemented to prevent the unintentional exposure to pathogens and toxins, or their accidental release". It defines biorisk management as "the analysis of ways and development of strategies to minimize the likelihood of the occurrence of biorisks".
The term "biocontainment" is related to laboratory biosafety. Merriam-Webster's online dictionary reports the first use of the term in 1966, defined as "the containment of extremely pathogenic organisms (such as viruses) usually by isolation in secure facilities to prevent their accidental release especially during research".
The term laboratory biosafety refers to the measures taken "to reduce the risk of accidental release of or exposure to infectious disease agents", whereas laboratory biosecurity is usually taken to mean "a set of systems and practices employed in legitimate bioscience facilities to reduce the risk that dangerous biological agents will be stolen and used maliciously".
Containment types
Laboratory context
Primary containment is the first
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https://en.wikipedia.org/wiki/Fucus%20spiralis
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Fucus spiralis is a species of seaweed, a brown alga (Heterokontophyta, Phaeophyceae), living on the littoral shore of the Atlantic coasts of Europe and North America. It has the common names of spiral wrack and flat wrack.
Description
Fucus spiralis is olive brown in colour and similar to Fucus vesiculosus and Fucus serratus. It grows to about 30 cm long and branches somewhat irregularly dichotomous and is attached, generally to rock, by a discoid holdfast. The flattened blade has a distinct mid-rib and is usually spirally twisted without a serrated edge, as in Fucus serratus, and it does not show air-vesicles, as Fucus vesiculosus.
Life history
The reproductive bodies form rounded swollen tips on the branches, usually in pairs.
In the conceptacles oögonia and antheridia are produced after meiosis and then released. Fertilisation follows and the zygote develops directly into the diploid sporophyte plant.
Ecology
The other common species of Fucus on the coasts of British Isles: Fucus spiralis, Fucus vesiculosus and Fucus serratus along with Ascophyllum nodosum form the main and dominant seaweeds on rocky shores. These three species, along with two others Pelvetia canaliculata and Ascophyllum nodosum form the zones along the shore.
Distribution
F. spiralis is common on the coasts all around the British Isles, western coasts of Europe, Canary Islands and North-eastern America.
Chemistry
Fucus spiralis produces phlorotannins of both the fucol and fucophlorethol types.
See also
Fucus vesiculosus
Fucus serratus
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https://en.wikipedia.org/wiki/Kojic%20acid
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Kojic acid is an organic compound with the formula . It is a derivative of 4-pyrone that functions in nature as a chelation agent produced by several species of fungi, especially Aspergillus oryzae, which has the Japanese common name koji. Kojic acid is a by-product in the fermentation process of malting rice, for use in the manufacturing of sake, the Japanese rice wine. It is a mild inhibitor of the formation of pigment in plant and animal tissues, and is used in food and cosmetics to preserve or change colors of substances. It forms a bright red complex with ferric ions.
Biosynthesis
13C-Labeling studies have revealed at least two pathways to kojic acid. In the usual route, dehydratase enzymes convert glucose to kojic acid. Pentoses are also viable precursors in which case dihydroxyacetone is invoked as an intermediate.
Applications
Kojic acid may be used on cut fruits to prevent oxidative browning, in seafood to preserve pink and red colors, and in cosmetics to lighten skin. As an example of the latter, it is used to treat skin diseases like melasma. Kojic acid also has antibacterial and antifungal properties.
The cocrystals of kojic acid with quercetin were found to have two times better cytotoxic activity to human cervical cancer cells (HeLa) and human colon cancer cells (Caco-2) in comparison with quercetin itself.
Other effects
Kojic acid has been shown to protect Chinese hamster ovary cells against ionizing radiation-induced damage. When exposed to a lethal dose of 3 Gy gamma radiation, dogs pretreated with kojic acid had a 51-day survival rate of 66.7% while the control group died within 16 days.
Chemical reactions
Deprotonation of the ring-OH group converts kojic acid to kojate. Kojate chelates to iron(III), forming a red complex . This kind of reaction may be the basis of the biological function of kojic aicd, that is, to solubilize ferric iron.
Being a multifunctional molecule, kojic acid has diverse organic chemistry. The hydroxymethyl group
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https://en.wikipedia.org/wiki/Airline%20codes
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This is a list of airline codes. The table lists IATA's two-character airline designators, ICAO's three-character airline designators and the airline call signs (telephony designator). Historical assignments are also included.
IATA airline designator
IATA airline designators, sometimes called IATA reservation codes, are two-character codes assigned by the International Air Transport Association (IATA) to the world's airlines. The standard is described in IATA's Standard Schedules Information Manual and the codes themselves are described in IATA's Airline Coding Directory. (Both are published semiannually.)
The IATA codes were originally based on the ICAO designators which were issued in 1947 as two-letter airline identification codes (see the section below). IATA expanded the two-character-system with codes consisting of a letter and a digit (or vice versa) e.g. EasyJet's U2 after ICAO had introduced its current three-letter-system in 1982. Until then only combinations of letters were used.
Airline designator codes follow the format xx(a), i.e., two alphanumeric characters (letters or digits) followed by an optional letter. Although the IATA standard provides for three-character airline designators, IATA has not used the optional third character in any assigned code. This is because some legacy computer systems, especially the "central reservations systems", have failed to comply with the standard, notwithstanding the fact that it has been in place for twenty years. The codes issued to date comply with IATA Resolution 762, which provides for only two characters. These codes thus comply with the current airline designator standard, but use only a limited subset of its possible range.
There are three types of designator: unique, numeric/alpha and controlled duplicate (explained below):
IATA airline designators are used to identify an airline for commercial purposes in reservations, timetables, tickets, tariffs, air waybills and in telecommunications.
A fli
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https://en.wikipedia.org/wiki/Hayashi%20track
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The Hayashi track is a luminosity–temperature relationship obeyed by infant stars of less than in the pre-main-sequence phase (PMS phase) of stellar evolution. It is named after Japanese astrophysicist Chushiro Hayashi. On the Hertzsprung–Russell diagram, which plots luminosity against temperature, the track is a nearly vertical curve. After a protostar ends its phase of rapid contraction and becomes a T Tauri star, it is extremely luminous. The star continues to contract, but much more slowly. While slowly contracting, the star follows the Hayashi track downwards, becoming several times less luminous but staying at roughly the same surface temperature, until either a radiative zone develops, at which point the star starts following the Henyey track, or nuclear fusion begins, marking its entry onto the main sequence.
The shape and position of the Hayashi track on the Hertzsprung–Russell diagram depends on the star's mass and chemical composition. For solar-mass stars, the track lies at a temperature of roughly 4000 K. Stars on the track are nearly fully convective and have their opacity dominated by hydrogen ions. Stars less than are fully convective even on the main sequence, but their opacity begins to be dominated by Kramers' opacity law after nuclear fusion begins, thus moving them off the Hayashi track. Stars between 0.5 and develop a radiative
zone prior to reaching the main sequence. Stars between 3 and are fully radiative at the beginning of the pre-main-sequence. Even heavier stars are born onto the main sequence, with no PMS evolution.
At an end of a low- or intermediate-mass star's life, the star follows an analogue of the Hayashi track, but in reverse—it increases in luminosity, expands, and stays at roughly the same temperature, eventually becoming a red giant.
History
In 1961, Professor Chushiro Hayashi published two papers that led to the concept of the pre-main-sequence and form the basis of the modern understanding of early stellar evolution
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https://en.wikipedia.org/wiki/Superior%20transverse%20scapular%20ligament
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The superior transverse ligament (transverse or suprascapular ligament) converts the suprascapular notch into a foramen or opening.
It is a thin and flat fascicle, narrower at the middle than at the extremities, attached by one end to the base of the coracoid process and by the other to the medial end of the scapular notch.
The suprascapular nerve always runs through the foramen; while the suprascapular vessels cross over the ligament in most of the cases.
The suprascapular ligament can become completely or partially ossified. The ligament also been found to split forming doubled space within the suprascapular notch.
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https://en.wikipedia.org/wiki/Suprascapular%20notch
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The suprascapular notch (or scapular notch) is a notch in the superior border of the scapula, just medial to the base of the coracoid process. It is converted into the suprascapular canal by the suprascapular ligament.
Structure
This notch is converted into a foramen by the suprascapular ligament, and serves for the passage of the suprascapular nerve. The suprascapular vessels vary in number as well as in their course as they run at the suprascapular notch site. The suprascapular artery pass above the suprascapular ligament in most cases. The suprascapular vein may pass through the suprascapular notch or it may instead pass superior to the suprascapular ligament.
Types
Two main classification systems exists with others being modified approaches of the same principle.
Typing based on subjective observation of the suprascapular notch shape. Introduced by and modified by .
There are six basic types of scapular notch:
Type I: Notch is absent. The superior border forms a wide depression from the medial angle to the coracoid process.
Type II: Notch is a blunted V-shape occupying the middle third of the superior border.
Type III: Notch is U-shaped with nearly parallel margins.
Type IV: Notch is V-shaped and very small. A shallow groove is frequently formed for the suprascapular nerve adjacent to the notch.
Type V: Notch is minimal and U-shaped with a partially ossified ligament.
Type VI: Notch is a foramen as the ligament is completely ossified.
Typing based on parametric measurements of depth to upper width ratio of the suprascapular notch introduced by and modified by .
There are five basic types of scapular notch:
Type I: Depth larger than upper width.
Type II: Depth equal to upper width.
Type III: Depth is smaller than upper width.
Type IV: Notch is a foramen.
Type V: Discrete notch.
The second method of suprascapular notch typing yields more practical approach in clinical diagnosis of the suprascapular nerve entrapment.
Clinical significance
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https://en.wikipedia.org/wiki/Great%20scapular%20notch
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The great scapular notch (or spinoglenoid notch) is a notch which serves to connect the supraspinous fossa and infraspinous fossa. It lies immediately medial to the attachment of the acromion to the lateral angle of the scapular spine.
The suprascapular artery and suprascapular nerve pass around the great scapular notch anteroposteriorly.
Supraspinatus and infraspinatus are both supplied by the suprascapular nerve, which originates from the superior trunk of the brachial plexus (roots C5-C6).
Additional images
See also
Suprascapular notch
Suprascapular canal
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https://en.wikipedia.org/wiki/Inferior%20transverse%20ligament%20of%20scapula
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The inferior transverse ligament (spinoglenoid ligament) is a weak membranous band, situated behind the neck of the scapula and stretching from the lateral border of the spine to the margin of the glenoid cavity.
It forms an arch under which the transverse scapular vessels and suprascapular nerve enter the infraspinatous fossa.
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https://en.wikipedia.org/wiki/Tekoteko
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Tekoteko is a Māori language term for a carved human form (either the whole body or head), either freestanding or attached to the gable of a whare (house).
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https://en.wikipedia.org/wiki/Social%20Choice%20and%20Individual%20Values
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Kenneth Arrow's monograph Social Choice and Individual Values (1951, 2nd ed., 1963, 3rd ed., 2012) and a theorem within it created modern social choice theory, a rigorous melding of social ethics and voting theory with an economic flavor. Somewhat formally, the "social choice" in the title refers to Arrow's representation of how social values from the set of individual orderings would be implemented under the constitution. Less formally, each social choice corresponds to the feasible set of laws passed by a "vote" (the set of orderings) under the constitution even if not every individual voted in favor of all the laws.
The work culminated in what Arrow called the "General Possibility Theorem," better known thereafter as Arrow's (impossibility) theorem. The theorem states that, absent restrictions on either individual preferences or neutrality of the constitution to feasible alternatives, there exists no social choice rule that satisfies a set of plausible requirements. The result generalizes the voting paradox, which shows that majority voting may fail to yield a stable outcome.
Introduction
The Introduction contrasts voting and markets with dictatorship and social convention (such as those in a religious code). Both exemplify social decisions. Voting and markets facilitate social choice in a sense, whereas dictatorship and convention limit it. The former amalgamate possibly differing tastes to make a social choice. The concern is with formal aspects of generalizing such choices. In this respect it is comparable to analysis of the voting paradox from use of majority rule as a value.
Arrow asks whether other methods of taste aggregation (whether by voting or markets), using other values, remedy the problem or are satisfactory in other ways. Here logical consistency is one check on acceptability of all the values. To answer the questions, Arrow proposes removing the distinction between voting and markets in favor of a more general category of collectiv
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https://en.wikipedia.org/wiki/Recombineering
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Recombineering (recombination-mediated genetic engineering) is a genetic and molecular biology technique based on homologous recombination systems, as opposed to the older/more common method of using restriction enzymes and ligases to combine DNA sequences in a specified order. Recombineering is widely used for bacterial genetics, in the generation of target vectors for making a conditional mouse knockout, and for modifying DNA of any source often contained on a bacterial artificial chromosome (BAC), among other applications.
Development
Although developed in bacteria, much of the inspiration for recombineering techniques came from methods first developed in Saccharomyces cerevisiae where a linear plasmid was used to target genes or clone genes off the chromosome. In addition, recombination with single-strand oligonucleotides (oligos) was first shown in Saccharomyces cerevisiae. Recombination was observed to take place with oligonucleotides as short as 20 bases.
Recombineering is based on homologous recombination in Escherichia coli mediated by bacteriophage proteins, either RecE/RecT from Rac prophage or Redαβδ from bacteriophage lambda. The lambda Red recombination system is now most commonly used and the first demonstrations of Red in vivo genetic engineering were independently made by Kenan Murphy and Francis Stewart. However, Murphy's experiments required expression of RecA and also employed long homology arms. Consequently, the implications for a new DNA engineering technology were not obvious. The Stewart lab showed that these homologous recombination systems mediate efficient recombination of linear DNA molecules flanked by homology sequences as short as 30 base pairs (40-50 base pairs are more efficient) into target DNA sequences in the absence of RecA. Now the homology could be provided by oligonucleotides made to order, and standard recA cloning hosts could be used, greatly expanding the utility of recombineering.
Recombineering with dsDNA
Recomb
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https://en.wikipedia.org/wiki/Porta%20hepatis
|
The porta hepatis or transverse fissure of the liver is a short but deep fissure, about 5 cm long, extending transversely beneath the left portion of the right lobe of the liver, nearer its posterior surface than its anterior border.
It joins nearly at right angles with the left sagittal fossa, and separates the quadrate lobe in front from the caudate lobe and process behind.
Function
It transmits the following (in anterior to posterior order):
common hepatic duct (leaving)
proper hepatic artery (entering)
hepatic portal vein (entering)
The hepatic duct lies in front and to the right, the hepatic artery to the left, and the portal vein behind and between the duct and artery.
It also transmits nerves and lymphatics.
Sympathetic nerves - these provide afferent pain impulses from the liver and gall bladder to the brain. Pain may be referred to the lower pole of the right scapula (T7).
Hepatic branch of the vagus nerve (CN X).
Location
The porta hepatis runs in the hepatoduodenal ligament.
When the patient is supine, and the liver observed inferiorly (as in a surgeon's perspective), the important structures demarcating its inferior aspect can be represented by a hepatic "H" figure. The right vertical limb of the "H" defines the left and right functional lobes, while the left vertical limb of the "H" defines the right and left anatomical lobes. The horizontal line between the vertical limbs of the "H" represents the porta hepatis. The quadrate and caudate lobe lie superior and inferior to this line respectively.
See also
Portal triad
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https://en.wikipedia.org/wiki/Constraint%20algebra
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In theoretical physics, a constraint algebra is a linear space of all constraints and all of their polynomial functions or functionals whose action on the physical vectors of the Hilbert space should be equal to zero.
For example, in electromagnetism, the equation for the Gauss' law
is an equation of motion that does not include any time derivatives. This is why it is counted as a constraint, not a dynamical equation of motion. In quantum electrodynamics, one first constructs a Hilbert space in which Gauss' law does not hold automatically. The true Hilbert space of physical states is constructed as a subspace of the original Hilbert space of vectors that satisfy
In more general theories, the constraint algebra may be a noncommutative algebra.
See also
First class constraints
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https://en.wikipedia.org/wiki/Parallax%20Propeller
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The Parallax P8X32A Propeller is a multi-core processor parallel computer architecture microcontroller chip with eight 32-bit reduced instruction set computer (RISC) central processing unit (CPU) cores. Introduced in 2006, it is designed and sold by Parallax, Inc.
The Propeller microcontroller, Propeller assembly language, and Spin interpreter were designed by Parallax's cofounder and president, Chip Gracey. The Spin programming language and Propeller Tool integrated development environment (IDE) were designed by Chip Gracey and Parallax's software engineer Jeff Martin.
On August 6, 2014, Parallax Inc. released all of the Propeller 1 P8X32A hardware and tools as open-source hardware and software under the GNU General Public License (GPL) 3.0. This included the Verilog code, top-level hardware description language (HDL) files, Spin interpreter, PropellerIDE and SimpleIDE programming tools and compilers.
Multi-core architecture
Each of the eight 32-bit cores (termed a cog) has a central processing unit (CPU) which has access to 512 32-bit long words (2 KB) of instructions and data. Self-modifying code is possible and is used internally, for example, as the boot loader overwrites itself with the Spin Interpreter. Subroutines in Spin (object-based high-level code) use a call-return mechanism requiring use of a call stack. Assembly (PASM, low-level) code needs no call stack. Access to shared memory (32 KB random-access memory (RAM); 32 KB read-only memory (ROM)) is controlled via round-robin scheduling by an internal computer bus controller termed the hub. Each cog also has access to two dedicated hardware counters and a special video generator for use in generating timing signals for PAL, NTSC, VGA, servomechanism-control, and others.
Speed and power management
The Propeller can be clocked using either an internal, on-chip oscillator (providing a lower total part count, but sacrificing some accuracy and thermal stability) or an external crystal oscillator or cera
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https://en.wikipedia.org/wiki/Potted%20shrimps
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Potted shrimps is a traditional British dish made with brown shrimp flavored with nutmeg and baked in butter. The butter acts as a preservative, and cayenne pepper may also be used. Regarded as a delicacy, it is traditionally eaten with bread.
Potted shrimps was a favourite dish of Ian Fleming, who passed on his predilection to his fictional creation James Bond. Fleming reputedly used to eat the dish at Scott's Restaurant on Mount Street in London.
See also
Food preservation
Hatchet Job of the Year
Potted meat
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https://en.wikipedia.org/wiki/Squeeze%20operator
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In quantum physics, the squeeze operator for a single mode of the electromagnetic field is
where the operators inside the exponential are the ladder operators. It is a unitary operator and therefore obeys , where is the identity operator.
Its action on the annihilation and creation operators produces
The squeeze operator is ubiquitous in quantum optics and can operate on any state. For example, when acting upon the vacuum, the squeezing operator produces the squeezed vacuum state.
The squeezing operator can also act on coherent states and produce squeezed coherent states. The squeezing operator does not commute with the displacement operator:
nor does it commute with the ladder operators, so one must pay close attention to how the operators are used. There is, however, a simple braiding relation,
Application of both operators above on the vacuum produces squeezed coherent states:
.
Derivation of action on creation operator
As mentioned above, the action of the squeeze operator on the annihilation operator can be written as To derive this equality, let us define the (skew-Hermitian) operator , so that .
The left hand side of the equality is thus . We can now make use of the general equality which holds true for any pair of operators and . To compute thus reduces to the problem of computing the repeated commutators between and .
As can be readily verified, we haveUsing these equalities, we obtain
so that finally we get
See also
Squeezed coherent state
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https://en.wikipedia.org/wiki/UBB%2B1
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UBB+1 is shorthand for Ubiquitin-B+1, a frameshifted mutant arising from the Ubiquitin B gene. UBB+1 is thought to arise from molecular misreading, a poorly understood process. Molecular misreading introduces dinucleotide deletions (e.g. ΔGA, ΔGU) into mRNA transcripts. These deletions are not present in genomic DNA. UBB+1 has been observed in the hallmarks of Alzheimer's disease, as well as other tauopathies and in polyglutamine diseases (e.g. Huntington's disease) but not in synucleinopathies (e.g. Parkinson's disease). Since its discovery it has been shown in vitro and in vivo that UBB+1 inhibits the proteasome and gives rise to downstream effects (e.g. a behavioral phenotype; impaired contextual memory). In non-neuronal cells UBB+1 also accumulates suggesting a functional role in non-neuronal diseases. UBB+1 can be truncated by yeast's ubiquitin hydrolase 1 (YUH1) and ubiquitin C-terminal hydrolase L3 UCHL3 even though the glycine at position 76 has been substituted for a tyrosine.
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https://en.wikipedia.org/wiki/Zinc%20phosphide
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Zinc phosphide (Zn3P2) is an inorganic chemical compound. It is a grey solid, although commercial samples are often dark or even black. It is used as a rodenticide. Zn3P2 is a II-V semiconductor with a direct band gap of 1.5 eV and may have applications in photovoltaic cells. A second compound exists in the zinc-phosphorus system, zinc diphosphide (ZnP2).
Synthesis and reactions
Zinc phosphide can be prepared by the reaction of zinc with phosphorus; however, for critical applications, additional processing to remove arsenic compounds may be needed.
6 Zn + P4 → 2 Zn3P2
Another method of preparation include reacting tri-n-octylphosphine with dimethylzinc.
Zinc phosphide reacts with water to produce phosphine (PH3) and zinc hydroxide (Zn(OH)2):
Zn3P2 + 6 H2O → 2 PH3 + 3 Zn(OH)2
Structure
Zn3P2 has a room-temperature tetragonal form that converts to a cubic form at around 845 °C. In the room-temperature form there are discrete P atoms, zinc atoms are tetrahedrally coordinated and phosphorus six coordinate, with zinc atoms at 6 of the vertices of a distorted cube.
The crystalline structure of zinc phosphide is very similar to that of cadmium arsenide (Cd3As2), zinc arsenide (Zn3As2) and cadmium phosphide (Cd3P2). These compounds of the Zn-Cd-P-As quaternary system exhibit full continuous solid-solution.
Applications
Photovoltaics
Zinc phosphide is an ideal candidate for thin film photovoltaic applications, for it has strong optical absorption and an almost ideal band gap (1.5eV). In addition to this, both zinc and phosphorus are found abundantly in the Earth's crust, meaning that material extraction cost is low compared with that of other thin film photovoltaics. Both zinc and phosphorus are also nontoxic, which is not the case for other common commercial thin film photovoltaics, like cadmium telluride.
Researchers at the University of Alberta were the first to successfully synthesize colloidal zinc phosphide. Before this, researchers were able to
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https://en.wikipedia.org/wiki/Percutaneous%20epididymal%20sperm%20aspiration
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Percutaneous epididymal sperm aspiration (PESA) is a technique used to determine sperm counts in the event of a possible blockage of the vas deferens. It is an alternative to microepidydimal sperm aspiration (MESA), and aims to address the technical difficulty and cost of MESA. A small needle is inserted through the skin of the scrotum to collect sperm from the epididymis, where sperm are usually stored after production in the testes. It can also be used to extract sperm for intracytoplasmic sperm injection (ICSI).
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https://en.wikipedia.org/wiki/Takasago%20International%20Corporation
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is a major international producer of flavours and fragrances headquartered in Japan, with presence in 27 countries and regions worldwide. Takasago ranked 8th overall and 1st in Asia on the Global Top Food Flavours and Fragrances Companies list published by FoodTalks in 2021.
History
Takasago International Corporation was founded on 9 February 1920 as the Takasago Perfumery Company Limited. In 1938, the headquarters of Takasago was moved to Taihoku (modern-day Taipei), and in 1940, a branch office and factory were set up in Shanghai. In 1945, the Taipei headquarters and Shanghai office were taken over by Republic of China.
In 1951, the Takasago Chemical Company in Taipei was closed and a new company, Takasago Chemical Industry Company was founded. The new company later changed its name to Takasago Perfumery Industry Company and merged with Takasago Perfumery Company.
During the 1960s, Takasago established offices in New York City and Paris, and their headquarters were moved to Hatchoubori 2–11, Chūō Ward. In 1963, Takasago Company Limited was listed in the Tokyo 2nd stock market, but by 1969 they were listed in the Tokyo 1st stock market. Since then the company has opened offices around the world.
Takasago is a member of the European Flavour Association.
Awards and honors
In 2001, Takasago's member of Board of Directors Ryōji Noyori won the 2001 Nobel Prize for Chemistry for the study of chirally catalyzed hydrogenations.
Competitors
Major competitors of Takasago include Firmenich, Döhler, International Flavors and Fragrances, Givaudan, and Symrise.
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https://en.wikipedia.org/wiki/Lumbosacral%20plexus
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The anterior divisions of the lumbar nerves, sacral nerves, and coccygeal nerve form the lumbosacral plexus, the first lumbar nerve being frequently joined by a branch from the twelfth thoracic. For descriptive purposes this plexus is usually divided into three parts:
lumbar plexus
sacral plexus
pudendal plexus
Injuries to the lumbosacral plexus are predominantly witnessed as bone injuries. Lumbosacral trunk and sacral plexus palsies are common injury patterns.
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https://en.wikipedia.org/wiki/Spectinomycin
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Spectinomycin, sold under the tradename Trobicin among others, is an antibiotic useful for the treatment of gonorrhea infections. It is given by injection into a muscle.
Common side effects include pain at the area of injection, rash, nausea, fever, and trouble sleeping. Severe allergic reactions may occasionally occur. It is generally safe to use during pregnancy. It may be used by those who are allergic to penicillin or cephalosporins. It is in the aminocyclitol class of drugs and works by stopping the making of protein by certain bacteria.
Spectinomycin was discovered in 1961. It is on the World Health Organization's List of Essential Medicines. It is not available in the United States for human use. It is made from the bacterium Streptomyces spectabilis.
Medical uses
It is given by intramuscular injection to treat gonorrhea, especially in patients who are allergic to penicillins.
This antibiotic is no longer available in the United States for human use, but is still available for veterinary use.
Side effects
Side effects include itching, chills, stomach ache, and red rash.
Mechanism of action
Spectinomycin binds to the 30S subunit of the bacterial ribosome and interrupts protein synthesis.
One form of resistance has emerged in the 16S ribosomal RNA in Pasteurella multocida.
Biosynthetic mechanism
Biosynthesis of spectinomycin begins similar to all aminoglycosides, with the formation of an inositol ring. The difference is the initial modification that forms the inositol ring of spectinomycin. The process begins with a glucose-6-phosphate (1a), which is oxidized by NAD+ to form a ketone at C2 (2a). This ketone is then formed into a primary amine group through pyridoxal phosphate (PLP) and glutamine transamination (3a). This process is repeated again at C4 to form a second primary amine (4a). Once these two amines are present, the glucose ring is ready to be methylated through two S-adenosyl methionine molecules (5a). With this methylation, the glucose rin
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https://en.wikipedia.org/wiki/Submucosal%20plexus
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The submucosal plexus (Meissner's plexus, plexus of the submucosa, plexus submucosus) lies in the submucosa of the intestinal wall. The nerves of this plexus are derived from the myenteric plexus which itself is derived from the plexuses of parasympathetic nerves around the superior mesenteric artery. Branches from the myenteric plexus perforate the circular muscle fibers to form the submucosal plexus. Ganglia from the plexus extend into the muscularis mucosae and also extend into the mucous membrane.
They contain Dogiel cells. The nerve bundles of the submucosal plexus are finer than those of the myenteric plexus. Its function is to innervate cells in the epithelial layer and the smooth muscle of the muscularis mucosae.
14% of submucosal plexus neurons are sensory neurons – Dogiel type II, also known as enteric primary afferent neurons or intrinsic primary afferent neurons.
History
Meissners' plexus was described by German professor Georg Meissner.
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https://en.wikipedia.org/wiki/Vertical%20tangent
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In mathematics, particularly calculus, a vertical tangent is a tangent line that is vertical. Because a vertical line has infinite slope, a function whose graph has a vertical tangent is not differentiable at the point of tangency.
Limit definition
A function ƒ has a vertical tangent at x = a if the difference quotient used to define the derivative has infinite limit:
The first case corresponds to an upward-sloping vertical tangent, and the second case to a downward-sloping vertical tangent. The graph of ƒ has a vertical tangent at x = a if the derivative of ƒ at a is either positive or negative infinity.
For a continuous function, it is often possible to detect a vertical tangent by taking the limit of the derivative. If
then ƒ must have an upward-sloping vertical tangent at x = a. Similarly, if
then ƒ must have a downward-sloping vertical tangent at x = a. In these situations, the vertical tangent to ƒ appears as a vertical asymptote on the graph of the derivative.
Vertical cusps
Closely related to vertical tangents are vertical cusps. This occurs when the one-sided derivatives are both infinite, but one is positive and the other is negative. For example, if
then the graph of ƒ will have a vertical cusp that slopes up on the left side and down on the right side.
As with vertical tangents, vertical cusps can sometimes be detected for a continuous function by examining the limit of the derivative. For example, if
then the graph of ƒ will have a vertical cusp at x = a that slopes down on the left side and up on the right side.
Example
The function
has a vertical tangent at x = 0, since it is continuous and
Similarly, the function
has a vertical cusp at x = 0, since it is continuous,
and
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https://en.wikipedia.org/wiki/Eco-sufficiency
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Ecological sufficiency, or simply sufficiency, refers to the concept or strategy to reduce the environmental footprint of societies through moderating the need for energy, carbon and material-based services and products. The term was popularised by authors such as Thomas Princen, a professor at MIT, in his 2005 book ‘The Logic of Sufficiency’. As a goal, sufficiency is about ensuring that all humans can live a good life within planetary boundaries, meaning without overshooting the ecological limits of the Earth and thus limiting resource use and pollution. Princen argues that ‘seeking enough when more is possible is both intuitive and rational - personally, organizationally and ecologically. And under global ecological constraint, it is ethical.'
In order to operationalise sufficiency, principles and ideas of concrete actions and policies have been proposed by various authors. Sufficiency may be approached at the individual level as a personal attitude or life philosophy (such as in the ‘Sobriété heureuse’ concept of French environmentalist Pierre Rabhi, or Uwe Schneidewind‘s concept of the ‘Good Life’), as well as a core collective value that could amend the notion of liberal societies. In terms of lifestyles, it is strongly related to the concepts of voluntary simplicity and downshifting.
There are significant barriers to the widespread adoption of sufficiency, as it goes against current dominant social paradigms (economic growth focus, materialism, individualism, etc.). However, there are signs of change in some trends, be they motivated by environmental concerns or other co-benefits. Sufficiency usually triggers debates around the notions of needs, wants, and 'enoughness'. Its impact on the economy and the role of rebound effects are also challenges to be addressed.
The war in Ukraine and subsequent energy crisis in 2022 have put a significant pressure on energy supply, notably in Europe, and popularised the concept of sufficiency and sufficiency policies. F
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https://en.wikipedia.org/wiki/Diagonal%20band%20of%20Broca
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The diagonal band of Broca interconnects the amygdala and the septal area. It is one of the olfactory structures. It is situated upon the inferior aspect of the brain. It forms the medial margin of the anterior perforated substance.
It was described by the French neuroanatomist Paul Broca.
Structure
It consists of fibers that are said to arise in the parolfactory area, the gyrus subcallosus and the anterior perforated substance, and course backward in the longitudinal striae to the dentate gyrus and the hippocampal region.
This is a cholinergic bundle of nerve fibers posterior to the anterior perforated substance. It interconnects the subcallosal gyrus in the septal area with the hippocampus and lateral olfactory area.
Nuclei
Two structures are often described in this brain regions, namely the nuclei of the vertical and horizontal limbs of the diagonal band of Broca (nvlDBB and nhlDBB, respectively). nvlDBB projects to the hippocampal formation through the fornix and it is the second largest assembly of cholinergic neurons in the basal forebrain whereas nhlDBB projects to the olfactory bulb and it does not have a significant population of cholinergic neurons.
Development
It is one of the basal forebrain structures that are derived from the ventral telencephalon during development.
Function
Along with the septum pellucidum and medial septal nucleus, the diagonal band of Broca is believed to be involved in the generation of theta waves in the hippocampus. It also inhibits magnocellular neurosecretory cells via GABA interneurons.
Its behavior can be altered by nerve growth factor.
Pathology
A significant nvlDBB neuronal loss is seen in Lewy body dementia.
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https://en.wikipedia.org/wiki/Displacement%20operator
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In the quantum mechanics study of optical phase space, the displacement operator for one mode is the shift operator in quantum optics,
,
where is the amount of displacement in optical phase space, is the complex conjugate of that displacement, and and are the lowering and raising operators, respectively.
The name of this operator is derived from its ability to displace a localized state in phase space by a magnitude . It may also act on the vacuum state by displacing it into a coherent state. Specifically,
where is a coherent state, which is an eigenstate of the annihilation (lowering) operator.
Properties
The displacement operator is a unitary operator, and therefore obeys
,
where is the identity operator. Since , the hermitian conjugate of the displacement operator can also be interpreted as a displacement of opposite magnitude (). The effect of applying this operator in a similarity transformation of the ladder operators results in their displacement.
The product of two displacement operators is another displacement operator whose total displacement, up to a phase factor, is the sum of the two individual displacements. This can be seen by utilizing the Baker–Campbell–Hausdorff formula.
which shows us that:
When acting on an eigenket, the phase factor appears in each term of the resulting state, which makes it physically irrelevant.
It further leads to the braiding relation
Alternative expressions
The Kermack-McCrae identity gives two alternative ways to express the displacement operator:
Multimode displacement
The displacement operator can also be generalized to multimode displacement. A multimode creation operator can be defined as
,
where is the wave vector and its magnitude is related to the frequency according to . Using this definition, we can write the multimode displacement operator as
,
and define the multimode coherent state as
.
See also
Optical phase space
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https://en.wikipedia.org/wiki/Trichloroisocyanuric%20acid
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Trichloroisocyanuric acid is an organic compound with the formula (C3Cl3N3O3). It is used as an industrial disinfectant, bleaching agent and a reagent in organic synthesis. This white crystalline powder, which has a strong "chlorine odour," is sometimes sold in tablet or granule form for domestic and industrial use.
Synthesis
Trichloroisocyanuric acid is prepared from cyanuric acid via a reaction with chlorine gas and trisodium cyanurate.
Applications
The compound is a disinfectant, algicide and bactericide mainly for swimming pools and dyestuffs, and is also used as a bleaching agent in the textile industry. It is widely used in civil sanitation for pools and spas, preventing and curing diseases in animal husbandry and fisheries, fruit and vegetable preservation, wastewater treatment, as an algicide for recycled water in industry and air conditioning, in anti shrink treatment for woolens, for treating seeds and in organic chemical synthesis. It is used in chemical synthesis as an easy to store and transport chlorine gas source, it is not subject to hazardous gas shipping restrictions, and its reaction with hydrochloric acid produces relatively pure chlorine.
Trichloroisocyanuric acid as used in swimming pools is easier to handle than chlorine gas. It dissolves slowly in water, but as it reacts, cyanuric acid concentration in the pool will build-up.
See also
Comet (cleanser)
Dichloroisocyanuric acid (Dichlor)
Sodium dichloroisocyanurate
Chlorine
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https://en.wikipedia.org/wiki/Flexibility%20%28engineering%29
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Flexibility is used as an attribute of various types of systems. In the field of engineering systems design, it refers to designs that can adapt when external changes occur. Flexibility has been defined differently in many fields of engineering, architecture, biology, economics, etc. In the context of engineering design one can define flexibility as the ability of a system to respond to potential internal or external changes affecting its value delivery, in a timely and cost-effective manner. Thus, flexibility for an engineering system is the ease with which the system can respond to uncertainty in a manner to sustain or increase its value delivery. Uncertainty is a key element in the definition of flexibility. Uncertainty can create both risks and opportunities in a system, and it is with the existence of uncertainty that flexibility becomes valuable.
Flexible Manufacturing System
Flexibility has been especially thoroughly studied for manufacturing systems. For manufacturing science eleven different classes of flexibility have been identified [Browne, 1984], [Sethi and Sethi, 1990]:
Machine flexibility - The different operation types that a machine can perform.
Material handling flexibility - The ability to move the products within a manufacturing facility.
Operation flexibility - The ability to produce a product in different ways.
Process flexibility - The set of products that the system can produce.
Product flexibility - The ability to add new products in the system.
Routing flexibility - The different routes (through machines and workshops) that can be used to produce a product in the system.
Volume flexibility - The ease to profitably increase or decrease the output of an existing system. At firm level, it is the ability of a firm to operate profitably at different output levels. Firms often use volume flexibility as a benchmark to assess their performance vis-à-vis their competitors.
Expansion flexibility - The ability to build out the capacity of a
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https://en.wikipedia.org/wiki/Hirschberg%20test
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In the fields of optometry and ophthalmology, the Hirschberg test, also Hirschberg corneal reflex test, is a screening test that can be used to assess whether a person has strabismus (ocular misalignment).
A photographic version of the Hirschberg is used to quantify strabismus.
Technique
It is performed by shining a light in the person's eyes and observing where the light reflects off the corneas. In a person with normal ocular alignment the light reflex lies slightly nasal from the center of the cornea (approximately 11 prism diopters—or 0.5mm from the pupillary axis), as a result of the cornea acting as a temporally-turned convex mirror to the observer. When doing the test, the light reflexes of both eyes are compared, and will be symmetrical in an individual with normal fixation. For an abnormal result, based on where the light lands on the cornea, the examiner can detect if there is an exotropia (abnormal eye is turned out), esotropia (abnormal eye is turned in), hypertropia (abnormal eye higher than the normal one) or hypotropia (abnormal eye is lower than the normal one).
Interpretation
In exotropia the light lands on the medial aspect of the cornea. In esotropia the light lands on the lateral aspect of the cornea. In hypertropia the light lands on the inferior aspect of the cornea. In hypotropia the light lands on the superior aspect of the cornea. A cover test can tell you the extent of the eso/exo-tropia.
Individuals can suffer from several tropias at once. In Graves ophthalmopathy, it is not uncommon to see an esotropia (due to pathology of the medial rectus muscle) co-morbid with a hypotropia (due to pathology of the inferior rectus muscle).
Krimsky Test
The Krimsky test is essentially the Hirschberg test, but with prisms employed to quantitate deviation of ocular misalignment by determining how much prism is required to centre the reflex The Krimsky test is advisably used for patients with tropias, but not with phorias.
History
The technique
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https://en.wikipedia.org/wiki/Parallel%20Element%20Processing%20Ensemble
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The Parallel Element Processing Ensemble (PEPE) was one of the very early parallel computing systems. Bell began researching the concept in the mid-1960s as a way to provide high-performance computing support for the needs of anti-ballistic missile (ABM) systems. The goal was to build a computer system that could simultaneously track hundreds of incoming ballistic missile warheads. A single PEPE system was built by Burroughs Corporation in the 1970s, by which time the US Army's ABM efforts were winding down. The design later evolved into the Burroughs Scientific Computer for commercial sales, but a lack of sales prospects led to it being withdrawn from the market.
PEPE came about as a result of predictions of the sorts of ICBM forces that would be expected in the event of an all-out Soviet attack during the 1970s. Missile fleets of both the US and USSR were growing through the 1960s, but a bigger issue was the number of warheads as a result of the move to multiple independently targetable reentry vehicles (MIRV). Computers designed for the Nike-X system were largely similar to systems like the IBM 7030, and would have been able to handle attacks with perhaps a dozen warheads arriving simultaneously. With MIRV, hundreds of targets, both warheads and decoys, would arrive at the same time, and the CPUs being used simply did not have the performance needed to analyze their trajectories quickly enough to leave time to attack them.
An initial testbed system, the "IC model", was built with 16 processors consisting of individual integrated circuits and connected to an IBM 360/65 host. This proved successful, and Burroughs won the contract to build a prototype of the full-sized 288-processor version in the early 1970s. The design featured an array of 288 (8 × 36) identical processing elements and associative addressing. Each processing element contained a minimum of control logic, the bulk of the control being concentrated in a common control unit. The control unit read in
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https://en.wikipedia.org/wiki/Affiliated%20operator
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In mathematics, affiliated operators were introduced by Murray and von Neumann in the theory of von Neumann algebras as a technique for using unbounded operators to study modules generated by a single vector. Later Atiyah and Singer showed that index theorems for elliptic operators on closed manifolds with infinite fundamental group could naturally be phrased in terms of unbounded operators affiliated with the von Neumann algebra of the group. Algebraic properties of affiliated operators have proved important in L2 cohomology, an area between analysis and geometry that evolved from the study of such index theorems.
Definition
Let M be a von Neumann algebra acting on a Hilbert space H. A closed and densely defined operator A is said to be affiliated with M if A commutes with every unitary operator U in the commutant of M. Equivalent conditions
are that:
each unitary U in M should leave invariant the graph of A defined by .
the projection onto G(A) should lie in M2(M).
each unitary U in M''' should carry D(A), the domain of A, onto itself and satisfy UAU* = A there.
each unitary U in M should commute with both operators in the polar decomposition of A.
The last condition follows by uniqueness of the polar decomposition. If A has a polar decomposition
it says that the partial isometry V should lie in M and that the positive self-adjoint operator |A| should be affiliated with M. However, by the spectral theorem, a positive self-adjoint operator commutes with a unitary operator if and only if each of its spectral projections
does. This gives another equivalent condition:
each spectral projection of |A| and the partial isometry in the polar decomposition of A lies in M.
Measurable operators
In general the operators affiliated with a von Neumann algebra M need not necessarily be well-behaved under either addition or composition. However in the presence of a faithful semi-finite normal trace τ and the standard Gelfand–Naimark–Segal action of M on H = L2(M, τ), E
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https://en.wikipedia.org/wiki/Actinic%20conjunctivitis
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Actinic conjunctivitis is an inflammation of the eye contracted from prolonged exposure to actinic (ultraviolet) rays. Symptoms are redness and swelling of the eyes. Most often the condition is caused by prolonged exposure to Klieg lights, therapeutic lamps or acetylene torches. Other names for the condition include Klieg conjunctivitis, eyeburn, arc-flash, welder's conjunctivitis, flash keratoconjunctivitis, actinic ray ophthalmia, X-ray ophthalmia and ultraviolet ray ophthalmia.
Symptoms
Conjunctivitis eye condition contracted from exposure to actinic rays. Symptoms are redness and swelling.
Causes
Conjunctivitis is prevalent among children of the highlands of Ecuador. The finding supports the hypothesis that prolonged exposure to the sun at altitude, in the less dense atmosphere (with the resultant lower UV absorption), is one cause of the condition.
Diagnosis
Management
See also
Conjunctivitis
Photokeratitis
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https://en.wikipedia.org/wiki/Day-night%20average%20sound%20level
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The day-night average sound level (Ldn or DNL) is the average noise level over a 24-hour period. The noise level measurements between the hours of 22:00 and 07:00 are artificially increased by 10 dB before averaging. This noise is weighted to take into account the decrease in community background noise of 10 dB during this period. There is a similar metric called day-evening-night average sound level (Lden or DENL) commonly used in other countries, or community noise exposure level (CNEL) used in California legislation; that is, the DNL with the addition of an evening period from 19:00 to 22:00 when noise level measurements are boosted 5 dB (or 4.77 dB in the case of CNEL) to account for the approximate decrease in background community noise during this period.
In the US, the Federal Aviation Administration has established this measure as a community noise exposure metric to aid airport noise analyses under Federal Aviation Regulation Part 150. The FAA says that a maximum day-night average sound level of higher than 65 dB is incompatible with residential communities. Communities in affected areas may be eligible for mitigation such as soundproofing.
See also
Aircraft noise
Effective perceived noise in decibels rating of aircraft
Noise pollution
Noise measurement
Day–evening–night noise level, the EU equivalent
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https://en.wikipedia.org/wiki/Spherical%20model
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The spherical model is a model of ferromagnetism similar to the Ising model, which was solved in 1952 by T. H. Berlin and M. Kac. It has the remarkable property that for linear dimension d greater than four, the critical exponents that govern the behaviour of the system near the critical point are independent of d and the geometry of the system. It is one of the few models of ferromagnetism that can be solved exactly in the presence of an external field.
Formulation
The model describes a set of particles on a lattice containing N sites. Each site j of contains a spin which interacts only with its nearest neighbours and an external field H. It differs from the Ising model in that the are no longer restricted to , but can take all real values, subject to the constraint that
which in a homogeneous system ensures that the average of the square of any spin is one, as in the usual Ising model.
The partition function generalizes from that of the Ising model to
where is the Dirac delta function, are the edges of the lattice, and and , where T is the temperature of the system, k is Boltzmann's constant and J the coupling constant of the nearest-neighbour interactions.
Berlin and Kac saw this as an approximation to the usual Ising model, arguing that the -summation in the Ising model can be viewed as a sum over all corners of an N-dimensional hypercube in -space. The becomes an integration over the surface of a hypersphere passing through all such corners.
It was rigorously proved by Kac and C. J. Thompson that the spherical model is a limiting case of the N-vector model.
Equation of state
Solving the partition function and using a calculation of the free energy yields an equation describing the magnetization M of the system
for the function g defined as
The internal energy per site is given by
an exact relation relating internal energy and magnetization.
Critical behaviour
For the critical temperature occurs at absolute zero, resulting in no phase transi
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https://en.wikipedia.org/wiki/Crypt%20%28anatomy%29
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Crypts are anatomical structures that are narrow but deep invaginations into a larger structure.
One common type of anatomical crypt is the Crypts of Lieberkühn. However, it is not the only type: some types of tonsils also have crypts. Because these crypts allow external access to the deep portions of the tonsils, these tonsils are more vulnerable to infection.
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https://en.wikipedia.org/wiki/Hereditarily%20countable%20set
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In set theory, a set is called hereditarily countable if it is a countable set of hereditarily countable sets.
Results
The inductive definition above is well-founded and can be expressed in the language of first-order set theory.
Equivalent properties
A set is hereditarily countable if and only if it is countable, and every element of its transitive closure is countable. If the axiom of countable choice holds, then a set is hereditarily countable if and only if its transitive closure is countable.
The collection of all h. c. sets
The class of all hereditarily countable sets can be proven to be a set from the axioms of Zermelo–Fraenkel set theory (ZF) and is set is designated . In particular, the existence does not require any form of the axiom of choice. Constructive Zermelo-Freankel (CZF) does not prove the class to be a set.
Model theory
This class is a model of Kripke–Platek set theory with the axiom of infinity (KPI), if the axiom of countable choice is assumed in the metatheory.
If , then .
Generalizations
More generally, a set is hereditarily of cardinality less than κ if it is of cardinality less than κ, and all its elements are hereditarily of cardinality less than κ; the class of all such sets can also be proven to be a set from the axioms of ZF, and is designated . If the axiom of choice holds and the cardinal κ is regular, then a set is hereditarily of cardinality less than κ if and only if its transitive closure is of cardinality less than κ.
See also
Hereditarily finite set
Constructible universe
External links
"On Hereditarily Countable Sets" by Thomas Jech
Set theory
Large cardinals
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https://en.wikipedia.org/wiki/Berry%20mechanism
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The Berry mechanism, or Berry pseudorotation mechanism, is a type of vibration causing molecules of certain geometries to isomerize by exchanging the two axial ligands (see Figure at right) for two of the equatorial ones. It is the most widely accepted mechanism for pseudorotation and most commonly occurs in trigonal bipyramidal molecules such as PF5, though it can also occur in molecules with a square pyramidal geometry. The Berry mechanism is named after R. Stephen Berry, who first described this mechanism in 1960.
Berry mechanism in trigonal bipyramidal structure
The process of pseudorotation occurs when the two axial ligands close like a pair of scissors pushing their way in between two of the equatorial groups which scissor out to accommodate them. Both the axial and equatorial constituents move at the same rate of increasing the angle between the other axial or equatorial constituent. This forms a square based pyramid where the base is the four interchanging ligands and the tip is the pivot ligand, which has not moved. The two originally equatorial ligands then open out until they are 180 degrees apart, becoming axial groups perpendicular to where the axial groups were before the pseudorotation. This requires about 3.6 kcal/mol in PF5.
This rapid exchange of axial and equatorial ligands renders complexes with this geometry unresolvable (unlike carbon atoms with four distinct substituents), except at low temperatures or when one or more of the ligands is bi- or poly-dentate.
Berry mechanism in square pyramidal structure
The Berry mechanism in square pyramidal molecules (such as IF5) is somewhat like the inverse of the mechanism in bipyramidal molecules. Starting at the "transition phase" of bipyramidal pseudorotation, one pair of fluorines scissors back and forth with a third fluorine, causing the molecule to vibrate. Unlike with pseudorotation in bipyramidal molecules, the atoms and ligands which are not actively vibrating in the "scissor" motion are still
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https://en.wikipedia.org/wiki/Pseudorotation
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In chemistry, a pseudorotation is a set of intramolecular movements of attached groups (i.e., ligands) on a highly symmetric molecule, leading to a molecule indistinguishable from the initial one. The International Union of Pure and Applied Chemistry (IUPAC) defines a pseudorotation as a "stereoisomerization resulting in a structure that appears to have been produced by rotation of the entire initial molecule", the result of which is a "product" that is "superposable on the initial one, unless different positions are distinguished by substitution, including isotopic substitution."
Well-known examples are the intramolecular isomerization of trigonal bipyramidal compounds by the Berry pseudorotation mechanism, and the out-of-plane motions of carbon atoms exhibited by cyclopentane, leading to the interconversions it experiences between its many possible conformers (envelope, twist). Note, no angular momentum is generated by this motion. In these and related examples, a small displacement of the atomic positions leads to a loss of symmetry until the symmetric product re-forms (see image example below), where these displacements are typically along low-energy pathways. The Berry mechanism refers to the facile interconversion of axial and equatorial ligand in types of compounds, e.g. D3h-symmetric (shown). Finally, in a formal sense, the term pseudorotation is intended to refer exclusively to dynamics in symmetrical molecules, though mechanisms of the same type are invoked for lower symmetry molecules as well.
See also
Bailar twist
Ray–Dutt twist
Bartell mechanism
Fluxional molecule
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https://en.wikipedia.org/wiki/International%20Sanitary%20Conferences
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The International Sanitary Conferences were a series of 14 international meetings held in response to growing concerns about human disease epidemics. The first of the Sanitary Conferences was organized by the French Government in 1851 to standardize international quarantine regulations against the spread of cholera, plague, and yellow fever. In total 14 conferences took place from 1851 to 1938; the conferences played a major role in the formation of the Office international d'hygiène publique before World War II, and the World Health Organization in 1948.
Background
Efforts by governments to control disease eruptions trace their origins to the mid-fourteenth century. During this time period, the city-state of Venice (considered to be the first international center of commerce) was first to apply quarantine procedures to protect their population and territory against plague. However, it was not until the Second cholera pandemic in 1829, that European Governments would appoint medical missions to investigate the cause of an epidemic. Among others, the Royal Academy of Medicine of Paris in June 1831 sent Auguste Gérardin and Paul Gaimard on medical mission to Russia, Prussia, and Austria.
In 1834, by appointment from the Minister of Commerce, the Secretary of the Conseil supérieur de la santé, P. de. Ségur-Dupeyron, was task with creating a report on the sanitary regulations of Mediterranean countries. This report, called attention to numerous differing quarantine requirements among countries and to resulting unnecessary confusion. This document and over 15 years of continued perseverance by the French Government ultimately led to convening an international conference to standardise quarantine requirements against exotic diseases; the International Sanitary Conferences - 1851-1938.
Chronology
Paris, 1851
The first International Sanitary Conference opened in Paris on July 23, 1851. A total of twelve countries participated including Austria, Great Britain, Greece,
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https://en.wikipedia.org/wiki/Nerve%20%28category%20theory%29
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In category theory, a discipline within mathematics, the nerve N(C) of a small category C is a simplicial set constructed from the objects and morphisms of C. The geometric realization of this simplicial set is a topological space, called the classifying space of the category C. These closely related objects can provide information about some familiar and useful categories using algebraic topology, most often homotopy theory.
Motivation
The nerve of a category is often used to construct topological versions of moduli spaces. If X is an object of C, its moduli space should somehow encode all objects isomorphic to X and keep track of the various isomorphisms between all of these objects in that category. This can become rather complicated, especially if the objects have many non-identity automorphisms. The nerve provides a combinatorial way of organizing this data. Since simplicial sets have a good homotopy theory, one can ask questions about the meaning of the various homotopy groups πn(N(C)). One hopes that the answers to such questions provide interesting information about the original category C, or about related categories.
The notion of nerve is a direct generalization of the classical notion of classifying space of a discrete group; see below for details.
Construction
Let C be a small category. There is a 0-simplex of N(C) for each object of C. There is a 1-simplex for each morphism f : x → y in C. Now suppose that f: x → y and g : y → z are morphisms in C. Then we also have their composition gf : x → z. The diagram suggests our course of action: add a 2-simplex for this commutative triangle. Every 2-simplex of N(C) comes from a pair of composable morphisms in this way. The addition of these 2-simplices does not erase or otherwise disregard morphisms obtained by composition, it merely remembers that this is how they arise.
In general, N(C)k consists of the k-tuples of composable morphisms
of C. To complete the definition of N(C) as a simplicial set, w
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https://en.wikipedia.org/wiki/Palatine%20nerves
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The palatine nerves (descending branches) are distributed to the roof of the mouth, soft palate, tonsil, and lining membrane of the nasal cavity.
Most of their fibers are derived from the sphenopalatine branches of the maxillary nerve.
In older texts, they are usually categorized as three in number: anterior, middle, and posterior. (In newer texts, and in Terminologia anatomica, they are broken down into "greater palatine nerve" and "lesser palatine nerve".)
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https://en.wikipedia.org/wiki/Core%20electron
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Core electrons are the electrons in an atom that are not valence electrons and do not participate in chemical bonding. The nucleus and the core electrons of an atom form the atomic core. Core electrons are tightly bound to the nucleus. Therefore, unlike valence electrons, core electrons play a secondary role in chemical bonding and reactions by screening the positive charge of the atomic nucleus from the valence electrons.
The number of valence electrons of an element can be determined by the periodic table group of the element (see valence electron):
For main-group elements, the number of valence electrons ranges from 1 to 8 (ns and np orbitals).
For transition metals, the number of valence electrons ranges from 3 to 12 (ns and (n−1)d orbitals).
For lanthanides and actinides, the number of valence electrons ranges from 3 to 16 (ns, (n−2)f and (n−1)d orbitals).
All other non-valence electrons for an atom of that element are considered core electrons.
Orbital theory
A more complex explanation of the difference between core and valence electrons can be described with atomic orbital theory.
In atoms with a single electron the energy of an orbital is determined exclusively by the principle quantum number n. The n = 1 orbital has the lowest possible energy in the atom. For large n, the energy increases so much that the electron can easily escape from the atom. In single electron atoms, all energy levels with the same principle quantum number are degenerate, and have the same energy.
In atoms with more than one electron, the energy of an electron depends not only on the properties of the orbital it resides in, but also on its interactions with the other electrons in other orbitals. This requires consideration of the ℓ quantum number. Higher values of ℓ are associated with higher values of energy; for instance, the 2p state is higher than the 2s state. When ℓ = 2, the increase in energy of the orbital becomes large enough to push the energy of orbital above the energy
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