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https://en.wikipedia.org/wiki/MT81
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MT81 is a mycotoxin with antibiotic activity.
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https://en.wikipedia.org/wiki/Mike%20Tyson%27s%20tattoos
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The American former boxer Mike Tyson has four tattoos of note. Three—at least two of them prison tattoos—are portraits of men he respects: tennis player Arthur Ashe, Marxist revolutionary Che Guevara, and Chinese communist leader Mao Zedong. The fourth, a face tattoo influenced by the Māori style , was designed and inked by S. Victor Whitmill in 2003. Tyson associates it with the Māori being warriors and has called it his "warrior tattoo", a name that has also been used in the news media.
Tyson's face tattoo quickly proved iconic and has become strongly associated with him. Its Māori influence has been controversial, spurring claims of cultural appropriation. In 2011, Whitmill filed a copyright suit against Warner Bros. for using the design on the character Stu Price in The Hangover Part II. Warner Bros. responded with a number of defenses, including that tattoos are not copyrightable; supporting them, scholar David Nimmer argued that it violated the Thirteenth Amendment to the United States Constitution—which prohibits slavery—to give Whitmill copyright over part of Tyson's body. After initial comments by Judge Catherine D. Perry denying an injunction but affirming that tattoos are copyrightable, Whitmill and Warner Bros. settled for undisclosed terms, without disruption to the release of the film.
The legal action renewed claims of cultural appropriation but also saw some Māori artists defend Whitmill. Legal scholars have highlighted how the case juxtaposes Maōri and Anglo-American attitudes on ownership of images. Despite never making it to trial, the case has been widely discussed in the context of the copyrightability of tattoos, a matter which has never been fully resolved in the United States.
Portraits of Ashe, Guevara, and Mao
From 1992 to 1995, while in prison for the rape of Desiree Washington, Tyson read a large number of books, including works by Chinese communist leader Mao Zedong. Spike Lee sent Tyson a copy of tennis player Arthur Ashe's deathb
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https://en.wikipedia.org/wiki/Chemical%20computer
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A chemical computer, also called a reaction-diffusion computer, Belousov–Zhabotinsky (BZ) computer, or gooware computer, is an unconventional computer based on a semi-solid chemical "soup" where data are represented by varying concentrations of chemicals. The computations are performed by naturally occurring chemical reactions.
Background
Originally chemical reactions were seen as a simple move towards a stable equilibrium which was not very promising for computation. This was changed by a discovery made by Boris Belousov, a Soviet scientist, in the 1950s. He created a chemical reaction between different salts and acids that swing back and forth between being yellow and clear because the concentration of the different components changes up and down in a cyclic way. At the time this was considered impossible because it seemed to go against the second law of thermodynamics, which says that in a closed system the entropy will only increase over time, causing the components in the mixture to distribute themselves until equilibrium is gained and making any changes in the concentration impossible. But modern theoretical analyses shows sufficiently complicated reactions can indeed comprise wave phenomena without breaking the laws of nature. (A convincing directly visible demonstration was achieved by Anatol Zhabotinsky with the Belousov–Zhabotinsky reaction showing spiraling colored waves.)
The wave properties of the BZ reaction means it can move information in the same way as all other waves. This still leaves the need for computation, performed by conventional microchips using the binary code transmitting and changing ones and zeros through a complicated system of logic gates. To perform any conceivable computation it is sufficient to have NAND gates. (A NAND gate has two bits input. Its output is 0 if both bits are 1, otherwise it's 1). In the chemical computer version logic gates are implemented by concentration waves blocking or amplifying each other in different wa
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https://en.wikipedia.org/wiki/Eel%20City
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Eel City is the name given to a community of deep-sea eels living amongst hydrothermal vents in the new volcano of Nafanua in American Samoa. It is unique because most hydrothermal vents are predominantly inhabited by invertebrates, whereas there is little invertebrate life in Eel City.
The community of eels was discovered in 2005, when a new volcanic cone, Nafanua, was discovered inside the submerged caldera of Vailulu'u volcanic sea mount. The eels were identified as synapobranchid eels Dysommina rugosa, which are known from trawl samples in both the Atlantic and Pacific oceans, but have never before been studied in their natural habitat. They are deep sea fishes, bottom dwellers, up to 37 cm long.
Preliminary work indicates that they use the vent only as a place to live. They seem to feed not on chemosynthetic bacteria, but on crustaceans that pass by Nafanua's summit in the currents.
During the initial dive in March 2005, one of the discoverers, Hubert Staudigel (a geologist at San Diego's Scripps Institution of Oceanography), commented "I suppose it's possible they migrate up the water column and feed in the water column and migrate back down to the cracks and crevices to hang out. But it seems odd that a deep-sea fish that would normally be experiencing 2- to 5-degree Celsius (35.6 degrees to 41 degrees Fahrenheit) water would be seeking out water that is warmer."
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https://en.wikipedia.org/wiki/Still%20life%20%28cellular%20automaton%29
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In Conway's Game of Life and other cellular automata, a still life is a pattern that does not change from one generation to the next. The term comes from the art world where a still life painting or photograph depicts an inanimate scene. In cellular automata, a still life can be thought of as an oscillator with unit period.
Classification
A pseudo still life consists of two or more adjacent islands (connected components) which can be partitioned (either individually or as sets) into non-interacting subparts, which are also still lifes. This compares with a strict still life, which may not be partitioned in this way. A strict still life may have only a single island, or it may have multiple islands that depend on one another for stability, and thus cannot be decomposed. The distinction between the two is not always obvious, as a strict still life may have multiple connected components all of which are needed for its stability. However, it is possible to determine whether a still life pattern is a strict still life or a pseudo still life in polynomial time by searching for cycles in an associated skew-symmetric graph.
Examples
There are many naturally occurring still lifes in Conway's Game of Life. A random initial pattern will leave behind a great deal of debris, containing small oscillators and a large variety of still lifes.
The most common still life (i.e. that most likely to be generated from a random initial state) is the block. A pair of blocks placed side-by-side (or bi-block) is the simplest pseudo still life. Blocks are used as components in many complex devices, an example being the Gosper glider gun.
The second most common still life is the hive (or beehive). Hives are frequently created in (non-interacting) sets of four, in a formation known as a honey farm.
The third most common still life is the loaf. Loaves are often found together in a pairing known as a bi-loaf. Bi-loaves themselves are often created in a further (non-interacting) pairin
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https://en.wikipedia.org/wiki/Ace%20of%20Aces%20%28video%20game%29
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Ace of Aces is a combat flight simulation video game developed by Artech Digital Entertainment and published in 1986 by Accolade in North America and U.S. Gold in Europe.
It was released for the Amstrad CPC, Atari 8-bit family, Atari 7800, Commodore 64, MSX, MS-DOS, Master System, and ZX Spectrum. Set in World War II, the player flies a RAF Mosquito long range fighter-bomber equipped with rockets, bombs and a cannon. Missions include destroying German fighter planes, bombers, V-1 flying bombs, U-boats, and trains. In 1988 Atari Corporation released a version on cartridge styled for the then-new Atari XEGS.
Ace of Aces received mixed reviews but went on to become one of the best-selling Commodore 64 video games published by Accolade. The game sold 100,000 units.
Gameplay
Upon launching the game a menu screen with options to either practice or partake in a proper mission is shown. If the player decides to do the practice mode, they can choose whether to do dog fight training or a U-boat or train bombing. When playing the practice mode, the enemies are less aggressive. There are five different view options — the cockpit, both left and right wings, the navigational map and the bomb bay — which can be accessed by using the keyboard or by double-tapping the fire button and moving the joystick to the desired direction.
When in missions, the player controls a twin-engined balsa RAF Mosquito which is already airborne, mitigating the necessity of takeoff. When starting a mission, the player chooses what supplies they wish to bring, but the more the player brings the lower the maximum speed of the plane. At the end of missions, landing is not required and points are awarded according to how many enemies are shot down, along with the amount of unused fuel, bombs, and missiles.
When missions are completed, the player can choose to combine two or more of the other missions to produce a mashup.
Reception
Commodore 64
In a 1987 Compute! article, Ace of Aces was noted as Acco
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https://en.wikipedia.org/wiki/Gateway%20%28telecommunications%29
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A gateway is a piece of networking hardware or software used in telecommunications networks that allows data to flow from one discrete network to another. Gateways are distinct from routers or switches in that they communicate using more than one protocol to connect multiple networks and can operate at any of the seven layers of the open systems interconnection model (OSI).
The term gateway can also loosely refer to a computer or computer program configured to perform the tasks of a gateway, such as a default gateway or router, and in the case of HTTP, gateway is also often used as a synonym for reverse proxy. It can also refer to a device installed in homes that combines router and modem functionality into one device, used by ISPs, also called a residential gateway.
Network gateway
A network gateway provides a connection between networks and contains devices, such as protocol translators, impedance matchers, rate converters, fault isolators, or signal translators. A network gateway requires the establishment of mutually acceptable administrative procedures between the networks using the gateway. Network gateways, known as protocol translation gateways or mapping gateways, can perform protocol conversions to connect networks with different network protocol technologies. For example, a network gateway connects an office or home intranet to the Internet. If an office or home computer user wants to load a web page, at least two network gateways are accessed—one to get from the office or home network to the Internet and one to get from the Internet to the computer that serves the web page.
On an Internet Protocol (IP) network, IP packets with a destination outside a given subnetwork are sent to the network gateway. For example, if a private network has a base IPv4 address of 192.168.1.0 and has a subnet mask of 255.255.255.0, then any data addressed to an IP address outside of 192.168.1.0–192.168.1.255 is sent to the network gateway. IPv6 networks work in a similar w
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https://en.wikipedia.org/wiki/Animal%20and%20Plant%20Health%20Agency
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The Animal and Plant Health Agency (APHA), formerly known as the Animal Health and Veterinary Laboratories Agency (AHVLA), is an executive agency of the Department for Environment, Food and Rural Affairs (Defra) of the United Kingdom.
It was formed in its current state on 1 October 2014, when AHVLA was expanded by adding parts of the Food and Environment Research Agency (FERA), including the Plant Health and Seeds Inspectorate (PHSI). AHVLA had originally been established on 1 April 2011 by a merger of two former agencies, Animal Health and the Veterinary Laboratories Agency.
The agency's main task is to protect the health and welfare of animals, as well as the general public, from disease. It conducts work across Great Britain on behalf of Defra, the Scottish Government and the Welsh Government.
The agency's total expenditure for the fiscal year 2016/17 was £217.3 million. This was offset by operating income of £62.6 million giving net expenditure of £154.7 million.
See also
National Office of Animal Health
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https://en.wikipedia.org/wiki/Statary
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Statary is a term currently applied in fields such as ecology, ethology, psychology. In modern use it contrasts on the one hand with such concepts as migratory, nomadic, or shifting, and on the other with static or immobile. The word also is of historical interest in its change of meaning as its usage changed.
Current usage
In current usage in fields such as biology, statary commonly means in a particular location or state, but not rigidly so. Army ant colonies for example are said to be in a statary phase when they occupy one bivouac for an extended period instead of just overnight. This is as opposed to a nomadic phase, in which they travel and forage practically daily. This does not mean that ant colonies in a statary phase do not move nor even that they do not forage while statary; they often do both, sometimes daily. Correspondingly a colony in a nomadic phase does not travel without rest; it bivouacs for the night. The significance of the terms is that the colonies' behaviour patterns differ radically according to their activity phase; one pattern favours maintaining a persistent presence where brood is being raised, whereas the other favours continual nomadic wandering into new foraging grounds. Such phases have raised interest in studies in aspects of comparative psychology and evolution.
The term statary also applies in contexts other than ants or colonial organisms. Swarm-forming species of locusts go beyond having statary and nomadic phases of behaviour; their growing nymphs actually develop into different adult morphologies, depending on whether the conditions during their growth favour swarming or not. Locusts that adopt the swarming morphology are said to be the migratory morphs, while the rest are called statary morphs. Effectively similar morphs occur in some other insect species, such as army worm.
In some technical fields statary need not refer literally to location or motion, but refer figuratively to their having particular characteristic but
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https://en.wikipedia.org/wiki/French%20ship%20Pourquoi%20Pas%3F%20%282005%29
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Pourquoi Pas ? () is a research vessel built in Saint-Nazaire, France by Alstom Marine for IFREMER and the French Navy. She is currently primarily used by SHOM (Service hydrographique et océanographique de la Marine). She was ordered in December 2002 and completed in July 2005. The 66 million euro cost was financed by IFREMER (55%) and the French Navy (45%). She is named after explorer Jean-Baptiste Charcot's famous ship. A space is required immediately before a question mark in French orthography, and accordingly, in French Pourquoi Pas ? is the correct way to write the name.
Pourquoi Pas ? is used 150 days per year by the French Navy and 180 days per year by IFREMER. She was designed for hydrography, geoscience, and physical, chemical, and biological oceanography, as well as to launch small submarines such as the crewed submersible Nautile and the ROV .
Notably, Pourquoi Pas ? has been used for the 2007 deployment and connection operations for the ANTARES neutrino telescope.
In 2008, Pourquoi Pas ? was used for the initial testing and operations of the PERISCOP, a pressurized deep sea fish recovery device.
In June 2009 she assisted in the recovery of Air France Flight 447.
External links
Pourquoi-Pas ? site at IFREMER
Netmarine
BBC article about the PERISCOP
This article was translated from the original article from the French Wikipedia, in 2006.
IFREMER
Research vessels of France
Pourquoi Pas?
2004 ships
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https://en.wikipedia.org/wiki/Suzuki%20graph
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The Suzuki graph is a strongly regular graph with parameters . Its automorphism group has order 896690995200 and contains as a subgroup of order 2 the Suzuki sporadic group. It is named for Michio Suzuki.
External links
A. E. Brouwer's website: the Suzuki graph
MathWorld: Suzuki graph
Individual graphs
Regular graphs
Strongly regular graphs
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https://en.wikipedia.org/wiki/Pulse-Doppler%20radar
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A pulse-Doppler radar is a radar system that determines the range to a target using pulse-timing techniques, and uses the Doppler effect of the returned signal to determine the target object's velocity. It combines the features of pulse radars and continuous-wave radars, which were formerly separate due to the complexity of the electronics.
The first operational Pulse Doppler radar was in the CIM-10 Bomarc, an American long range supersonic missile powered by ramjet engines, and which was armed with a W40 nuclear weapon to destroy entire formations of attacking enemy aircraft. Pulse-Doppler systems were first widely used on fighter aircraft starting in the 1960s. Earlier radars had used pulse-timing in order to determine range and the angle of the antenna (or similar means) to determine the bearing. However, this only worked when the radar antenna was not pointed down; in that case the reflection off the ground overwhelmed any returns from other objects. As the ground moves at the same speed but opposite direction of the aircraft, Doppler techniques allow the ground return to be filtered out, revealing aircraft and vehicles. This gives pulse-Doppler radars "look-down/shoot-down" capability. A secondary advantage in military radar is to reduce the transmitted power while achieving acceptable performance for improved safety of stealthy radar.
Pulse-Doppler techniques also find widespread use in meteorological radars, allowing the radar to determine wind speed from the velocity of any precipitation in the air. Pulse-Doppler radar is also the basis of synthetic aperture radar used in radar astronomy, remote sensing and mapping. In air traffic control, they are used for discriminating aircraft from clutter. Besides the above conventional surveillance applications, pulse-Doppler radar has been successfully applied in healthcare, such as fall risk assessment and fall detection, for nursing or clinical purposes.
History
The earliest radar systems failed to operate as ex
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https://en.wikipedia.org/wiki/Knots%20Unravelled
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Knots Unravelled: From String to Mathematics is a book on the mathematics of knots, intended for schoolchildren and other non-mathematicians. It was written by mathematician Meike Akveld and mathematics publisher Andrew Jobbings, and published in 2011 by Arbelos, Jobbings's firm.
Topics
The main problem studied in the book is the use of knot invariants to test whether a loop is knotted or distinguish knots from each other. It has seven short chapters, separated by "interludes" providing examples including Celtic knots, knotted papercraft, neckties, ropework, torus knots, and a form of the trefoil knot that can only sit on a plane with two points in contact. Small exercises, called "tasks" and often involving practical experiments rather than mathematical calculation, are scattered throughout the book, with answers at the end.
The first chapter is introductory, and the second describes knot diagrams and the Reidemeister moves that change one diagram to another without changing the underlying knot. The next three chapters discuss particular knot invariants. These begin with the crossing number of a knot, the minimum number of crossings in its diagrams. Chapter four discusses another invariant, the unknotting number, the minimum number of local changes to a diagram that can unknot a given knot, while also discussing chirality (the phenomenon of a knot being different from its mirror image) and composite knots. Chapter five covers tricolorability, an invariant defined by coloring the arcs of a diagram according to certain rules. Chapter six generalizes the problem from knots to links, systems of more than two loops that cannot be separated from each other. The final chapter, necessarily more mathematical than the others, is on the Jones polynomial.
Other material in the book includes historical asides, pointers to research topics, many illustrations, and an appendix with a table of small knots.
Audience and reception
This book is unusual among books on knot theory,
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https://en.wikipedia.org/wiki/Julie%20Stewart%20%28food%20scientist%29
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Julie Stewart was a food scientist. She began working at Stouffer's Food's in 1957, first starting in the shipping department and then moving into food development. She was an aide to Doris Davis Centini at Stouffer's Food's during development of the Stouffer's portions of the Apollo 11 space crew's meals eaten in quarantine on their return from space in 1969. Her responsibilities included designing recipes, and NASA selected one of her recipes, Salisbury Stroganoff, for inclusion in the Apollo 11 crew's menu.
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https://en.wikipedia.org/wiki/Fuller%20calculator
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The Fuller calculator, sometimes called Fuller's cylindrical slide rule, is a cylindrical slide rule with a helical main scale taking 50 turns around the cylinder. This creates an instrument of considerable precision – it is equivalent to a traditional slide rule long. It was invented in 1878 by George Fuller, professor of engineering at Queen's University Belfast, and despite its size and price it remained on the market for nearly a century because it outperformed nearly all other slide rules.
As with other slide rules, the Fuller is limited to calculations based on multiplication and division with additional scales allowing for trigonometical and exponential functions. The mechanical calculators produced in the same era were generally restricted to addition and subtraction with only advanced versions, like the Arithmometer, able to multiply and divide. Even these advanced machines could not perform trigonometry or exponentiation and they were bigger, heavier and much more expensive than the Fuller. In the mid-twentieth century the handheld Curta mechanical calculator became available which also competed in convenience and price. However, for scientific calculations the Fuller remained viable until 1973 when it was made obsolete by the HP-35 handheld scientific electronic calculator.
Design
Model 1, the standard model
In essence, the calculator consists of three separate hollow cylindrical parts that can twist and slide over each other about a common axis without any tendency to slip. The following details describe the version made between 1921 and 1935. There is a papier-mâché cylinder (marked D in the annotated photograph) some long and in diameter fastened to a mahogany handle. A second papier-mâché cylinder (marked C) – long and diameter – is a slide fit over the first. Both cylinders are covered in paper varnished with shellac. The second, outer, cylinder is printed with the slide rule's primary logarithmic scale in the form of a 50-turn helix long
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https://en.wikipedia.org/wiki/HEPN%20domain
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In molecular biology, the HEPN domain (higher eukaryotes and prokaryotes nucleotide-binding domain) is a region of approximately 110 amino acids found in the C terminus of sacsin, a chaperonin implicated in an early-onset neurodegenerative disease in human, and in many bacterial and archaea proteins. There are three classes of proteins with HEPN domains:
Single-domain HEPN proteins found in many bacteria.
Two-domain proteins with N-terminal nucleotidyltransferase (NT) and C- terminal HEPN domains. This N-terminal NT domain belongs to a large family of NTs, which includes several classes of enzymes that are responsible for some types of bacterial resistance to aminoglycosides. These enzymes deactivate various antibiotics by transferring a nucleotidyl group to the drug.
A multidomain sacsin protein in genomes of fish and mammals. The HEPN domain is located at the C terminus of the protein, directly after the DnaJ domain. The crystal structure of the HEPN domain from the TM0613 protein of Thermotoga maritima indicates that it is structurally similar to the C-terminal all-alpha-helical domain of kanamycin nucleotidyltransferases (KNTases). It is composed of five alpha helices, three of which form an up- and-down helical bundle, with a pair of short helices on the side. The distant structural similarity suggests that the HEPN domain might be involved in nucleotide binding.
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https://en.wikipedia.org/wiki/Ragel
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Ragel is a finite-state machine compiler and a parser generator. Initially Ragel supported output for C, C++ and Assembly source code, and was expanded to support several other languages including Objective C, D, Go, Ruby, and Java. Additional language support is also in development. It supports the generation of table or control flow driven state machines from regular expressions and/or state charts and can also build lexical analysers via the longest-match method. Ragel specifically targets text parsing and input validation.
Overview
Ragel supports the generation of table or control flow driven state machines from regular expressions and/or state charts and can also build lexical analysers via the longest-match method.
A unique feature of Ragel is that user actions can be associated with arbitrary state machine transitions using operators that are integrated into the regular expressions. Ragel also supports visualization of the generated machine via graphviz.
The above graph represents a state-machine that takes user input as a series of bytes representing ASCII characters and control codes. 48..57 is equivalent to the regular expression [0-9] (i.e. any digit), so only sequences beginning with a digit can be recognised. If 10 (line feed) is encountered, we're done. 46 is the decimal point ('.'), 43 and 45 are positive and negative signs ('+', '-') and 69/101 is uppercase/lowercase 'e' (to indicate a number in scientific format). As such it will recognize the following properly:
2
45
055
78.1
2e5
78.3e12
69.0e-3
3e+3
but not:
.3
46.
-5
3.e2
2e5.1
Syntax
Ragel's input is a regular expression only in the sense that it describes a regular language; it is usually not written in a concise regular expression, but written out into multiple parts like in Extended Backus–Naur form. For example, instead of supporting POSIX character classes in regex syntax, Ragel implements them as built-in production rules. As with usual parser generators, Ragel allows for handling
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https://en.wikipedia.org/wiki/List%20of%20fish%20and%20seafood%20soups
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This is a list of soups made with fish or seafood.
Seafood soups
Bisque, usually lobster bisque
Bouillabaisse — a Provencal dish, especially in the port of Marseilles
Buridda
Caldillo de congrio
Caldillo de perro
Cantonese seafood soup
Chowder
Bermuda fish chowder
Clam chowder
Fish chowder
Spiced haddock chowder
Chupe
Cioppino
Clam soup
Cullen skink
Dashi
Fish soup
Fish soup bee hoon
Fish tea
Halászlé - Hungarian spicy fish soup
Gumbo – often includes seafood, made with shrimp or crab stock
Ikan kuah kuning — a Maluku and Papua dish
Herring soup
Jaecheopguk
Lohikeitto
Lung fung soup
Maeutang
Mohinga
Moqueca
Paila marina
Phở – some versions use seafood
Pindang
Psarosoupa
She-crab soup
Sliced fish soup
Sopa marinera — a Spanish seafood dish made with oysters, clams, seashells, crab, lobster, shrimp and spices like achiote and cumin
Sopa de peixe - Portuguese fish soup, usually made using a tomato base. Very rich, it can include a variety of different seafood at the same time, and be a meal in itself.
Tom Yum
Ukha
See also
Fish soup
List of cream soups
List of fish soups
List of soups
List of seafood dishes
List of stews
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https://en.wikipedia.org/wiki/Elongated%20square%20bipyramid
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In geometry, the elongated square bipyramid (or elongated octahedron) is one of the Johnson solids (). As the name suggests, it can be constructed by elongating an octahedron by inserting a cube between its congruent halves.
It has been named the pencil cube or 12-faced pencil cube due to its shape.
A zircon crystal is an example of an elongated square bipyramid.
Formulae
The following formulae for volume (), surface area () and height () can be used if all faces are regular, with edge length :
Dual polyhedron
The dual of the elongated square bipyramid is called a square bifrustum and has 10 faces: 8 trapezoidal and 2 square.
Related polyhedra and honeycombs
A special kind of elongated square bipyramid without all regular faces allows a self-tessellation of Euclidean space. The triangles of this elongated square bipyramid are not regular; they have edges in the ratio 2::.
It can be considered a transitional phase between the cubic and rhombic dodecahedral honeycombs. The cells are here colored white, red, and blue based on their orientation in space. The square pyramid caps have shortened isosceles triangle faces, with six of these pyramids meeting together to form a cube. The dual of this honeycomb is composed of two kinds of octahedra (regular octahedra and triangular antiprisms), formed by superimposing octahedra into the cuboctahedra of the rectified cubic honeycomb. Both honeycombs have a symmetry of [[4,3,4]].
Cross-sections of the honeycomb, through cell centers produces a chamfered square tiling, with flattened horizontal and vertical hexagons, and squares on the perpendicular polyhedra.
With regular faces, the elongated square bipyramid can form a tessellation of space with tetrahedra and octahedra. (The octahedra can be further decomposed into square pyramids.) This honeycomb can be considered an elongated version of the tetrahedral-octahedral honeycomb.
See also
Elongated square pyramid
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https://en.wikipedia.org/wiki/Nectaplum
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A nectaplum (interspecific nectarine) is a tradename for varieties that are a hybrid of nectarines and plums developed by Floyd Zaiger. Both nectarine and plum traits are easily detectable. It sprouts from an ornamental tree which makes it popular for home gardening, but is not large in the commercial market.
The fruit's exterior has smooth skin closely resembling a nectarine. Nectaplums are noted for their sweetness (due to a very high sugar content) and their intense flavor.
Varieties
There is currently only one marketed variety of this type of fruit.
Spice Zee - Slightly acidic, loaded with sugar. White flesh, and reddish-grey skin. Harvests in middle to late July.
See also
Peacotum
Plumcot, Apriplum, Pluot, or Aprium
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https://en.wikipedia.org/wiki/Zope%20Object%20Database
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The Zope Object Database (ZODB) is an object-oriented database for transparently and persistently storing Python objects. It is included as part of the Zope web application server, but can also be used independently of Zope.
Features of the ZODB include: transactions, history/undo, transparently pluggable storage, built-in caching, multiversion concurrency control (MVCC), and scalability across a network (using ).
History
Created by Jim Fulton of Zope Corporation in the late 90s.
Started as simple Persistent Object System (POS) during Principia development (which later became Zope)
ZODB 3 was renamed when a significant architecture change was landed.
ZODB 4 was a short lived project to re-implement the entire ZODB 3 package using 100% Python.
Implementation
Basics
ZODB stores Python objects using an extended version of Python's built-in object persistence (pickle). A ZODB database has a single root object (normally a dictionary), which is the only object directly made accessible by the database. All other objects stored in the database are reached through the root object. Objects referenced by an object stored in the database are automatically stored in the database as well.
ZODB supports concurrent transactions using MVCC and tracks changes to objects on a per-object basis. Only changed objects are committed. Transactions are non-destructive by default and can be reverted.
Example
For example, say we have a car described using 3 classes Car, Wheel and Screw. In Python, this could be represented the following way:
class Car: [...]
class Wheel: [...]
class Screw: [...]
myCar = Car()
myCar.wheel1 = Wheel()
myCar.wheel2 = Wheel()
for wheel in (myCar.wheel1, myCar.wheel2):
wheel.screws = [Screw(), Screw()]
If the variable mycar is the root of persistence, then:
zodb['mycar'] = myCar
This puts all of the object instances (car, wheel, screws etc.) into storage, which can be retrieved later. If another program gets a connection to the database through the
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https://en.wikipedia.org/wiki/Chung%20Laung%20Liu
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Chung Laung Liu (; 1934 – 7 November 2020), also known as David Liu or C. L. Liu, was a Taiwanese computer scientist. Born in Guangzhou, he spent his childhood in Macau. He received his B.Sc. degree in Taiwan, master's degree and doctorate in United States.
Biography
Liu received his B.Sc. degree (1956) at the National Cheng Kung University in Taiwan, and his S.M. and E.E. degrees (1960), and his Sc. D. degree (1962) at the Massachusetts Institute of Technology. He was on the faculty of the Massachusetts Institute of Technology (1962–1972) and the University of Illinois at Urbana-Champaign (1972–1998), where he was Associate Provost from 1995 to 1998. He then retired from UIUC and served as President and Professor of Computer Science at the National Tsing Hua University (NTHU) in Hsinchu, Taiwan from February 1998 to February 2002. He was the William Mong Honorary Chair Professor at National Tsing Hua University. He was a Visiting Professor at City University of Hong Kong, and at Waseda University, Tokyo, Japan, and Li K. T. Honorary Chair Professor at National Central University. Since 2007 he was Li Kuo-Ting Forum Professor at National Cheng Kung University.
He was the author and co-author of seven books and monographs, and over 180 technical papers. His research interests included computer-aided design of VLSI circuits, real-time systems, computer-aided instruction, combinatorial optimization, and discrete mathematics.
He received the IEEE Millennium Medal, and the IEEE Circuits and Systems Society Golden Jubilee Medal in 2000. He also received the IEEE Computer Society, Real Time Systems Technical Committee 1999 Technical Achievement Award (inaugural winner) for his contributions in the area of real time scheduling, and the IEEE Circuits and Systems Society 1998 Technical Achievement Award for his contributions in the area of computer aided design of VLSI circuits. He received an Outstanding Talents Foundation Award in 1998. He was the recipient of the 1994 I
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https://en.wikipedia.org/wiki/EEMBC
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EEMBC, the Embedded Microprocessor Benchmark Consortium, is a non-profit, member-funded organization formed in 1997, focused on the creation of standard benchmarks for the hardware and software used in embedded systems. The goal of its members is to make EEMBC benchmarks an industry standard for evaluating the capabilities of embedded processors, compilers, and the associated embedded system implementations, according to objective, clearly defined, application-based criteria. EEMBC members may contribute to the development of benchmarks, vote at various stages before public distribution, and accelerate testing of their platforms through early access to benchmarks and associated specifications.
Most Popular Benchmark Working Groups
In chronological order of development:
AutoBench 1.1 - single-threaded code for automotive, industrial, and general-purpose applications
Networking - single-threaded code associated with moving packets in networking applications.
MultiBench - multi-threaded code for testing scalability of multicore processors.
CoreMark - measures the performance of central processing units (CPU) used in embedded systems
BXBench - system benchmark measuring the web browsing user-experience, from the click/touch on a URL to final page rendered on the screen, and is not limited to measuring only JavaScript execution.
AndEBench-Pro - system benchmark providing a standardized, industry-accepted method of evaluating Android platform performance. It's available for free download in Google Play.
FPMark - multi-threaded code for both single- and double-precision floating-point workloads, as well as small, medium, and large data sets.
ULPMark - energy-measuring benchmark for ultra-low power microcontrollers; benchmarks include ULPMark-Core (with a focus on microcontroller core activity and sleep modes) and ULPMark-Peripheral (with a focus on microcontroller peripheral activity such as Analog-to-digital converter, Serial Peripheral Interface Bus, Real-time
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https://en.wikipedia.org/wiki/Thermus%20aquaticus
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Thermus aquaticus is a species of bacteria that can tolerate high temperatures, one of several thermophilic bacteria that belong to the Deinococcota phylum. It is the source of the heat-resistant enzyme Taq DNA polymerase, one of the most important enzymes in molecular biology because of its use in the polymerase chain reaction (PCR) DNA amplification technique.
History
When studies of biological organisms in hot springs began in the 1960s, scientists thought that the life of thermophilic bacteria could not be sustained in temperatures above about . Soon, however, it was discovered that many bacteria in different springs not only survived, but also thrived in higher temperatures. In 1969, Thomas D. Brock and Hudson Freeze of Indiana University reported a new species of thermophilic bacteria which they named Thermus aquaticus. The bacterium was first isolated from Mushroom Spring in the Lower Geyser Basin of Yellowstone National Park, which is near the major Great Fountain Geyser and White Dome Geyser, and has since been found in similar thermal habitats around the world.
Biology
T. aquaticus shows best growth at 65–70 °C (149–158 °F), but can survive at temperatures of 50–80 °C (122–176 °F). It primarily scavenges for protein from its environment as is evidenced by the large number of extracellular and intracellular proteases and peptidases as well as transport proteins for amino acids and oligopeptides across its cell membrane. This bacterium is a chemotroph—it performs chemosynthesis to obtain food. However, since its range of temperature overlaps somewhat with that of the photosynthetic cyanobacteria that share its ideal environment, it is sometimes found living jointly with its neighbors, obtaining energy for growth from their photosynthesis. T. aquaticus normally respires aerobically but one of its strains, Thermus aquaticus Y51MC23, is able to be grown anaerobically.
The genetic material of T. aquaticus consists of one chromosome and four plasmids, and
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https://en.wikipedia.org/wiki/Z2%20%28computer%29
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The Z2 was an electromechanical (mechanical and relay-based) digital computer that was completed by Konrad Zuse in 1940. It was an improvement on the Z1 Zuse built in his parents' home, which used the same mechanical memory. In the Z2, he replaced the arithmetic and control logic with 600 electrical relay circuits, weighing over 600 pounds.
The Z2 could read 64 words from punch cards. Photographs and plans for the Z2 were destroyed by the Allied bombing during World War II. In contrast to the Z1, the Z2 used 16-bit fixed-point arithmetic instead of 22-bit floating point.
Zuse presented the Z2 in 1940 to members of the DVL (today DLR) and member , whose support helped fund the successor model Z3.
Specifications
See also
Z1
Z3
Z4
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https://en.wikipedia.org/wiki/Tonsil
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The tonsils are a set of lymphoid organs facing into the aerodigestive tract, which is known as Waldeyer's tonsillar ring and consists of the adenoid tonsil (or pharyngeal tonsil), two tubal tonsils, two palatine tonsils, and the lingual tonsils. These organs play an important role in the immune system.
When used unqualified, the term most commonly refers specifically to the palatine tonsils, which are two lymphoid organs situated at either side of the back of the human throat. The palatine tonsils and the adenoid tonsil are organs consisting of lymphoepithelial tissue located near the oropharynx and nasopharynx (parts of the throat).
Structure
Humans are born with four types of tonsils: the pharyngeal tonsil, two tubal tonsils, two palatine tonsils and the lingual tonsils.
Development
The palatine tonsils tend to reach their largest size in puberty, and they gradually undergo atrophy thereafter. However, they are largest relative to the diameter of the throat in young children. In adults, each palatine tonsil normally measures up to 2.5 cm in length, 2.0 cm in width and 1.2 cm in thickness.
The adenoid grows until the age of 5, starts to shrink at the age of 7 and becomes small in adulthood.
Function
The tonsils are immunocompetent organs which serve as the immune system's first line of defense against ingested or inhaled foreign pathogens, and as such frequently engorge with blood to assist in immune responses to common illnesses such as the common cold. The tonsils have on their surface specialized antigen capture cells called microfold cells (M cells) that allow for the uptake of antigens produced by pathogens. These M cells then alert the B cells and T cells in the tonsil that a pathogen is present and an immune response is stimulated. B cells are activated and proliferate in areas called germinal centers in the tonsil. These germinal centers are places where B memory cells are created and secretory antibody (IgA) is produced.
Clinical significance
Th
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https://en.wikipedia.org/wiki/Upjohn
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The Upjohn Company was a pharmaceutical manufacturing firm founded in 1886 in Hastings, Michigan, by Dr. William E. Upjohn who was an 1875 graduate of the University of Michigan medical school. The company was originally formed to make friable pills, which were specifically designed to be easily digested. They could be "reduced to a powder under the thumb", a strong marketing argument at the time.
History
Upjohn developed a process for the large scale production of cortisone. The oxygen atom at the 11 position in this steroid is an absolute requirement for biological activity. There are however no known natural sources for starting materials that contain that feature. The only method for preparing this drug prior to 1952 was a lengthy synthesis starting from cholic acid isolated from bile. In 1952, two Upjohn biochemists, Dury Peterson and Herb Murray announced that they were able to introduce this crucial oxygen atom by fermentation of the steroid progesterone with a common mold of the genus Rhizopus. Over the next several years a group of chemists headed by John Hogg developed a process for preparing cortisone from the soybean sterol stigmasterol. The microbiological oxygenation is a key step in this process.
Subsequently, Upjohn together with Schering biochemically converted cortisone into the more potent steroid prednisone by a bacterial fermentation. In chemical research, the company is known for the development of the Upjohn dihydroxylation by V. VanRheenen, R. C. Kelly, and D. Y. Cha in 1976. Upjohn's best known drugs before the acquisition by Pfizer were Xanax, Halcion, Motrin, Lincocin, and Rogaine.
In 1995, Upjohn merged with Pharmacia AB to form Pharmacia & Upjohn; the company was owned by Pfizer from 2002 until 2020.
In 2015, Pfizer resurrected the Upjohn name for a division which manufactures and licenses drugs for which patents have expired; as of 2019, it planned to divest itself of this business in 2020.
In July 2019, Pfizer announced plans t
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https://en.wikipedia.org/wiki/Metabigyrate%20rhombicosidodecahedron
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In geometry, the metabigyrate rhombicosidodecahedron is one of the Johnson solids (). It can be constructed as a rhombicosidodecahedron with two non-opposing pentagonal cupolae rotated through 36 degrees. It is also a canonical polyhedron.
Alternative Johnson solids, constructed by rotating different cupolae of a rhombicosidodecahedron, are:
The gyrate rhombicosidodecahedron () where only one cupola is rotated;
The parabigyrate rhombicosidodecahedron () where two opposing cupolae are rotated;
And the trigyrate rhombicosidodecahedron () where three cupolae are rotated.
External links
World of Polyhedra - metabigyrate rhombicosidodecahedron (interactive rotatable wireframe applet)
Johnson solids
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https://en.wikipedia.org/wiki/Tandem%20exon%20duplication
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Tandem exon duplication is defined as duplication of exons within the same gene to give rise to the subsequent exon. A complete exon analysis of all genes in Homo sapiens, Drosophila melanogaster, and Caenorhabditis elegans has shown 12,291 instances of tandem duplication in exons in human, fly, and worm. Analysis of the intronic region has produced further 4,660 unidentified duplicated exons referred to as unannotated exons. 1,578 of these unannotated exons contained stop codons thus not considered potential exons. 35.1% of the unannotated exons were found in the EST sequence thus confirming the potential of the presence of these exons in protein transcripts.
See also
Exon shuffling
Gene duplication
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https://en.wikipedia.org/wiki/Brake-specific%20fuel%20consumption
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Brake-specific fuel consumption (BSFC) is a measure of the fuel efficiency of any prime mover that burns fuel and produces rotational, or shaft power. It is typically used for comparing the efficiency of internal combustion engines with a shaft output.
It is the rate of fuel consumption divided by the power produced.
In traditional units, it measures fuel consumption in pounds per hour divided by the brake horsepower, lb/(hp⋅h); in SI units, this corresponds to the inverse of the units of specific energy, kg/J = s2/m2.
It may also be thought of as power-specific fuel consumption, for this reason. BSFC allows the fuel efficiency of different engines to be directly compared.
The term "brake" here as in "brake horsepower" refers to a historical method of measuring torque (see Prony brake).
The BSFC calculation (in metric units)
To calculate BSFC, use the formula
where:
is the fuel consumption rate in grams per second (g/s)
is the power produced in watts where (W)
is the engine speed in radians per second (rad/s)
is the engine torque in newton metres (N⋅m)
The above values of r, , and may be readily measured by instrumentation with an engine mounted in a test stand and a load applied to the running engine. The resulting units of BSFC are grams per joule (g/J)
Commonly BSFC is expressed in units of grams per kilowatt-hour (g/(kW⋅h)). The conversion factor is as follows:
BSFC [g/(kW⋅h)] = BSFC [g/J] × (3.6 × 106)
The conversion between metric and imperial units is:
BSFC [g/(kW⋅h)] = BSFC [lb/(hp⋅h)] × 608.277
BSFC [lb/(hp⋅h)] = BSFC [g/(kW⋅h)] × 0.001644
The relationship between BSFC numbers and efficiency
To calculate the actual efficiency of an engine requires the energy density of the fuel being used.
Different fuels have different energy densities defined by the fuel's heating value. The lower heating value (LHV) is used for internal-combustion-engine-efficiency calculations because the heat at temperatures below cannot be put to use.
Some example
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https://en.wikipedia.org/wiki/Session%20layer
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In the seven-layer OSI model of computer networking, the session layer is layer 5.
The session layer provides the mechanism for opening, closing and managing a session between end-user application processes, i.e., a semi-permanent dialogue. Communication sessions consist of requests and responses that occur between applications. Session-layer services are commonly used in application environments that make use of remote procedure calls (RPCs).
An example of a session-layer protocol is the OSI protocol suite session-layer protocol, also known as X.225 or ISO 8327. In case of a connection loss this protocol may try to recover the connection. If a connection is not used for a long period, the session-layer protocol may close it and re-open it. It provides for either full duplex or half-duplex operation and provides synchronization points in the stream of exchanged messages.
Other examples of session layer implementations include Zone Information Protocol (ZIP) – the AppleTalk protocol that coordinates the name binding process, and Session Control Protocol (SCP) – the DECnet Phase IV session-layer protocol.
Within the service layering semantics of the OSI network architecture, the session layer responds to service requests from the presentation layer and issues service requests to the transport layer.
Services
Connection establishment and release
At the minimum, the session layer allows the two sides to establish and use a connection, called a session, and allows orderly release of the connection.
In the OSI model, the transport layer is not responsible for an orderly release of a connection. Instead, the session layer is responsible for that. However, in modern TCP/IP networks, TCP already provides orderly closing of connections at the transport layer.
After a session connection is released, the underlying transport connection may be reused for another session connection. Also, a session connection may make use of multiple consecutive transport connections. F
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https://en.wikipedia.org/wiki/Viaspan
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Viaspan was the trademark under which the University of Wisconsin cold storage solution (also known as University of Wisconsin solution or UW solution) was sold. Currently, UW solution is sold under the Belzer UW trademark and others like Bel-Gen or StoreProtect. UW solution was the first solution designed for use in organ transplantation, and became the first intracellular-like preservation medium. Developed in the late 1980s by Folkert Belzer and James Southard for pancreas preservation, the solution soon displaced EuroCollins solution as the preferred medium for cold storage of livers and kidneys, as well as pancreas. The solution has also been used for hearts and other organs. University of Wisconsin cold storage solution remains what is often called the gold standard for organ preservation, despite the development of other solutions that are in some respects superior.
Development
The guiding principles for the development of UW Solution were:
osmotic concentration maintained by the use of metabolically inert substances like lactobionate and raffinose rather than with glucose
Hydroxyethyl starch (HES) is used to prevent edema
Substances are added to scavenge free radicals, along with steroids and insulin.
Composition
Potassium lactobionate: 100 mM
KH2PO4: 25 mM
MgSO4: 5 mM
Raffinose: 30 mM
Adenosine: 5 mM
Glutathione: 3 mM
Allopurinol: 1 mM
Hydroxyethyl starch: 50 g/L
See also
HTK Solution (Histidine-tryptophan-ketoglutarate)
Biostasis
Organ transplant
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https://en.wikipedia.org/wiki/Minimalism%20%28computing%29
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In computing, minimalism refers to the application of minimalist philosophies and principles in the design and use of hardware and software. Minimalism, in this sense, means designing systems that use the least hardware and software resources possible.
History
In the late 1970s and early 1980s, programmers worked within the confines of relatively expensive and limited resources of common platforms. Eight or sixteen kilobytes of RAM was common; 64 kilobytes was considered a vast amount and was the entire address space accessible to the 8-bit CPUs predominant during the earliest generations of personal computers. The most common storage medium was the 5.25 inch floppy disk holding from 88 to 170 kilobytes. Hard drives with capacities from five to ten megabytes cost thousands of dollars.
Over time, personal-computer memory capacities expanded by orders of magnitude and mainstream programmers took advantage of the added storage to increase their software's capabilities and to make development easier by using higher-level languages. By contrast, system requirements for legacy software remained the same. As a result, even the most elaborate, feature-rich programs of yesteryear seem minimalist in comparison with current software.
One example of a program whose system requirements once gave it a heavyweight reputation is the GNU Emacs text editor, which gained the backronym "Eight Megabytes And Constantly Swapping" in an era when 8 megabytes was a lot of RAM. Today, Emacs' mainly textual buffer-based paradigm uses far fewer resources than desktop metaphor GUI IDEs with comparable features such as Eclipse or Netbeans. In a speech at the 2002 International Lisp Conference, Richard Stallman indicated that minimalism was a concern in his development of GNU and Emacs, based on his experiences with Lisp and system specifications of low-end minicomputers at the time.
As the capabilities and system requirements of common desktop software and operating systems grew throughout th
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https://en.wikipedia.org/wiki/Costoxiphoid%20ligaments
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The costoxiphoid ligaments (chondroxiphoid ligaments) are inconstant strand-like fibrous bands that connect the anterior and posterior surfaces of the seventh costal cartilage, and sometimes those of the sixth, to the front and back of the xiphoid process the sternum.
They vary in length and breadth in different subjects; those on the back of the joint are less distinct than those in front.
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https://en.wikipedia.org/wiki/Archinephros
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The archinephros, or holonephros, is a primitive kidney that has been retained by the larvae of hagfish and some caecilians. A recent author has referred to this structure as "the hypothetical primitive kidney of ancestral vertebrates". In the earliest vertebrates, this structure potentially extended the entire length of the body and consisted of paired segmental structures which drained via a pair of archinephrenic ducts into the cloaca. The entire structure arises from the nephric ridge, which in higher animal embryos gives rise to nephrotomes and the pronephroi at around 4 weeks gestation in humans. The pronephroi are supplanted by mesonephroi and finally by definitive kidneys, the metanephroi, by around 5 weeks gestation. The archinephros is nonfunctional in humans and other mammals.
The three types of mature vertebrate kidneys develop from the archinephros: the pronephros from the front section, the mesonephros from the mid-section and the metanephros from the rear section.
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https://en.wikipedia.org/wiki/Sexual%20mimicry
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Sexual mimicry occurs when one sex mimics the opposite sex in its behavior, appearance, or chemical signalling.
It is more commonly seen within invertebrate species, although sexual mimicry is also seen among vertebrates such as spotted hyenas.
Sexual mimicry is commonly used as a mating strategy to gain access to a mate, a defense mechanism to avoid more dominant individuals, or a survival strategy. It can also be a physical characteristic that establishes an individual's place in society. Sexual mimicry is employed differently across species and it is part of their strategy for survival and reproduction.
Examples of intraspecific sexual mimicry in animals include the spotted hyena, certain types of fish, passerine birds and some species of insect.
Interspecific sexual mimicry can also occur in some plant species, especially orchids. In plants employing sexual mimicry, flowers mimic mating signals of their pollinator insects. These insects are attracted and pollinate the flowers through pseudocopulations or other sexual behaviors performed on the flower.
Social systems
Sexual mimicry can play a role in the development of a species' social system. Perhaps the most extreme example of this can be seen in the spotted hyena, Crocuta crocuta. Female hyenas of all ages possess pseudomasculinized genitalia, including a pseudopenis formed from the clitoris, and a false scrotum formed from the labia. These characteristics likely initially evolved to reduce rates of intrasex aggression received by cub and juvenile females from adult females. However, the trait has evolved beyond its initial use to become highly relevant to spotted hyena communication. Subordinate hyenas will greet dominant individuals by erecting their penis or pseudopenis and allowing the dominant individual to lick it. This likely initially evolved as a means of discerning the sex of the subordinate individual, as the pseudopenis less closely resembles a genuine penis when erect, and tasting the a
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https://en.wikipedia.org/wiki/Latvian%20National%20Encyclopedia
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The Latvian National Encyclopedia () is a universal encyclopedia in Latvian, which was published in 2018 to mark the centenary of the independence of Latvia. The National Encyclopaedia Editorial Office works as an affiliate of the Administration Branch of the National Library of Latvia.
Overview
Background
The first attempt at creating a national encyclopedia in independent Latvia was launched in the interwar period by the publishing house of . The first edition of the was published in 1927, but after 21 volumes (the last one ending with the article about Giovanni Battista Tiepolo) the work was cut short by the Soviet occupation of Latvia in 1940. The first complete encyclopedia, with content suited to Soviet ideology, was issued during the Soviet occupation as the Latvian Soviet Encyclopedia from 1981 to 1988.
Modern edition
The National Encyclopedia project was launched in late 2014. , a Latvian IT company, was selected as the provider of the electronic platform of the encyclopedia on 18 December 2014. The editorial board of the encyclopedia began its work in July 2015.
The making of the encyclopedia is supervised by the Council of the National Encyclopedia led by the Latvian Minister of Culture (Dace Melbārde at the time of the launch). The Board of Editors consists of four editors and the Chief Editor, Dr. hist. Valters Ščerbinskis, whereas the Professional Editor Board () is made up of 46 consultants, each assigned to a certain topic, and is led by National Library of Latvia director . From 2014 to 2018, annual budget funding towards the creation of the encyclopedia was €200-250 thousand, which in total amounted to €1,1 million.
The 864-page thick, first paper edition of the encyclopedia was released in October 2018 with a price tag of €38.50. It is thematically focused on Latvian topics and is dedicated to the Centenary of the Republic of Latvia. Due to high demand, the 3000 copies of the issue were sold out in a few days and an additional batch of 100
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https://en.wikipedia.org/wiki/Convex%20and%20Concave
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Convex and Concave is a lithograph print by the Dutch artist M. C. Escher, first printed in March 1955.
It depicts an ornate architectural structure with many stairs, pillars and other shapes. The relative aspects of the objects in the image are distorted in such a way that many of the structure's features can be seen as both convex shapes and concave impressions. This is a very good example of Escher's mastery in creating illusions of "impossible architecture." The windows, roads, stairs and other shapes can be perceived as opening out in seemingly impossible ways and positions. Even the image on the flag is of reversible cubes. One can view these features as concave by viewing the image upside-down.
All additional elements and decoration on the left are consistent with a viewpoint from above, while those on the right with a viewpoint from below: hiding half the image makes it very easy to switch between convex and concave.
Sources
Locher, J.L. (2000). The Magic of M. C. Escher. Harry N. Abrams, Inc. .
1955 prints
Works by M. C. Escher
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https://en.wikipedia.org/wiki/Ringworm%20affair
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The ringworm affair refers to circumstances involving an alleged number of 20,000 to 200,000 Jews who were treated between 1948 and 1960 for tinea capitis (ringworm) with ionizing radiation to the head and neck area within Israel. The population suffering from the disease in Israel at the time was composed primarily of newly-arrived immigrants and populations who were expected to emigrate, mostly from North Africa, as well as some from Middle East and elsewhere, but many Jewish children were irradiated in their home countries regardless of their intent to emigrate.
The irradiation of Mizrahi children is viewed by activists in Israel as the most salient example of injustices encountered in the 1950s as a result of shortcomings or irresponsibility on the part of authorities in the absorption in Israeli society of new immigrants.
Ringworm in Israel and Jewish communities
The scalp ringworm, also known as tinea capitis, mycosis, thrichophytia, and favus, was one of the most common fungal diseases in children in the Jewish communities in Israel and abroad since the 19th century. An X-ray treatment for ringworm has been used around the world as early as 1897. An estimated 200,000 children worldwide received X-ray treatment for tinea capitis in accordance with the standard Adamson-Kienbock procedure between 1910 and 1959, until griseofulvin, the first effective anti-fungal agent for ringworm, was introduced.
At the beginning of the 20th century, Hadassah Medical Center in Jerusalem treated ringworm disease among the religious Jewish community in Jerusalem using irradiation and the disease almost disappeared.
With mass immigration from Arab and Muslim countries in the 1940s and 1950s, many new cases of ringworm surfaced, primarily among immigrant children from Asia and North Africa, due to crowded living conditions with deficient hygiene facilities. At this time, ringworm was still treated with irradiation, under the supervision of Hadassah Medical Center (Prof. Dostr
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https://en.wikipedia.org/wiki/Biological%20pump
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The biological pump (or ocean carbon biological pump or marine biological carbon pump) is the ocean's biologically driven sequestration of carbon from the atmosphere and land runoff to the ocean interior and seafloor sediments. In other words, it is a biologically mediated process which results in the sequestering of carbon in the deep ocean away from the atmosphere and the land. The biological pump is the biological component of the "marine carbon pump" which contains both a physical and biological component. It is the part of the broader oceanic carbon cycle responsible for the cycling of organic matter formed mainly by phytoplankton during photosynthesis (soft-tissue pump), as well as the cycling of calcium carbonate (CaCO3) formed into shells by certain organisms such as plankton and mollusks (carbonate pump).
Budget calculations of the biological carbon pump are based on the ratio between sedimentation (carbon export to the ocean floor) and remineralization (release of carbon to the atmosphere).
The biological pump is not so much the result of a single process, but rather the sum of a number of processes each of which can influence biological pumping. Overall, the pump transfers about 10.2 gigatonnes of carbon every year into the ocean's interior and a total of 1300 gigatonnes carbon over an average 127 years. This takes carbon out of contact with the atmosphere for several thousand years or longer. An ocean without a biological pump would result in atmospheric carbon dioxide levels about 400 ppm higher than the present day.
Overview
The element carbon plays a central role in climate and life on Earth. It is capable of moving among and between the geosphere, cryosphere, atmosphere, biosphere and hydrosphere. This flow of carbon is referred to as the Earth's carbon cycle. It is also intimately linked to the cycling of other elements and compounds. The ocean plays a fundamental role in Earth's carbon cycle, helping to regulate atmospheric CO2 concentration.
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https://en.wikipedia.org/wiki/Gonadal%20dysgenesis
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Gonadal dysgenesis is classified as any congenital developmental disorder of the reproductive system
in humans. It is atypical development of gonads in an embryo,. One type of gonadal dysgenesis is the development of functionless, fibrous tissue, termed streak gonads, instead of reproductive tissue. Streak gonads are a form of aplasia, resulting in hormonal failure that manifests as sexual infantism and infertility, with no initiation of puberty and secondary sex characteristics.
Gonadal development is a process, which is primarily controlled genetically by the chromosomal sex (XX or XY), which directs the formation of the gonad (ovary or testicle).
Differentiation of the gonads requires a tightly regulated cascade of genetic, molecular and morphogenic events.
At the formation of the developed gonad, steroid production influences local and distant receptors for continued morphological and biochemical changes.
This results in the phenotype corresponding to the karyotype (46,XX for females and 46,XY for males).
Gonadal dysgenesis arises from a difference in signalling in this tightly regulated process during early foetal development.
Manifestations of gonadal dysgenesis are dependent on the aetiology and severity of the underlying causes.
Causes
Pure gonadal dysgenesis 46,XX also known as XX gonadal dysgenesis
Pure gonadal dysgenesis 46,XY also known as XY gonadal dysgenesis
Mixed gonadal dysgenesis also known as partial gonadal dysgenesis, and 45,X/46,XY mosaicism
Turner syndrome also known as 45,X or 45,X0
Endocrine disruptions
Pathogenesis
46,XX gonadal dysgenesis
46,XX gonadal dysgenesis is characteristic of female hypogonadism with a karyotype of 46,XX. Streak ovaries are present with non-functional tissues unable to produce the required sex steroid oestrogen.
Low levels of oestrogen effect the HPG axis with no feedback to the anterior pituitary to inhibit the secretion of FSH and LH.
FSH and LH are secreted at elevated levels. Increased levels of
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https://en.wikipedia.org/wiki/Xenobiotic
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A xenobiotic is a chemical substance found within an organism that is not naturally produced or expected to be present within the organism. It can also cover substances that are present in much higher concentrations than are usual. Natural compounds can also become xenobiotics if they are taken up by another organism, such as the uptake of natural human hormones by fish found downstream of sewage treatment plant outfalls, or the chemical defenses produced by some organisms as protection against predators.
The term xenobiotics, however, is very often used in the context of pollutants such as dioxins and polychlorinated biphenyls and their effect on the biota, because xenobiotics are understood as substances foreign to an entire biological system, i.e. artificial substances, which did not exist in nature before their synthesis by humans. The term xenobiotic is derived from the Greek words ξένος (xenos) = foreigner, stranger and βίος (bios) = life, plus the Greek suffix for adjectives -τικός, -ή, -όν (-tikos, -ē, -on).
Xenobiotics may be grouped as carcinogens, drugs, environmental pollutants, food additives, hydrocarbons, and pesticides.
Xenobiotic metabolism
The body removes xenobiotics by xenobiotic metabolism. This consists of the deactivation and the excretion of xenobiotics and happens mostly in the liver. Excretion routes are urine, feces, breath, and sweat. Hepatic enzymes are responsible for the metabolism of xenobiotics by first activating them (oxidation, reduction, hydrolysis, and/or hydration of the xenobiotic), and then conjugating the active secondary metabolite with glucuronic acid, sulfuric acid, or glutathione, followed by excretion in bile or urine. An example of a group of enzymes involved in xenobiotic metabolism is hepatic microsomal cytochrome P450. These enzymes that metabolize xenobiotics are very important for the pharmaceutical industry because they are responsible for the breakdown of medications. A species with this unique cytochrome P
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https://en.wikipedia.org/wiki/SQL-Ledger
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SQL-Ledger is an ERP and double entry accounting system. Accounting data is stored in an SQL database server and a standard web browser can be used as its user interface. The system uses the Perl language with a database interface module for processing and PostgreSQL for data storage which is the preferred platform. The download version also includes schemas for IBM's DB2 database server as well as Oracle.
Capabilities
SQL-Ledger offers all of the standard features of SMB accounting software. Specific customization is available as part of an enterprise support contract.
Not only is the user interface multi-lingual, but it also offers the ability to print out statements, invoices, and the like in the language of the customer, even if the user does not know the language in which the content is being printed.
Supported languages
Business model
DWS generates their revenue from selling a manual and customizations. For free, DWS provides the source code of the current and all the previous versions, installation instructions, an FAQ collection and a user forum.
Version 3.0 of this program was released under the GNU GPL 2.0 license.
Version 3.2.6 released in December 2017.
Licensing issues
At its inception, SQL-Ledger used the GNU GPL 2.0 license. In 2005, Debian legal questioned whether or not the program belonged in Free or Non-Free, due to wording in the Terms and Conditions notice in the tarball.
In late 2006, LedgerSMB was created as a secure fork of SQL-Ledger. In early 2007, SQL-Ledger 2.8 was released under the 'SQL-Ledger Open Source License, a license which retroactively revokes all previous licenses under which the covered code had been released. That version also contained an "anti-forking" clause.
However, within a month, SQL-Ledger 2.8.1 was released, under the GNU GPL 2.0.
See also
LedgerSMB, another fork of version 2.
Comparison of accounting software
List of free and open source software packages
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https://en.wikipedia.org/wiki/Bacterial%20artificial%20chromosome
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A bacterial artificial chromosome (BAC) is a DNA construct, based on a functional fertility plasmid (or F-plasmid), used for transforming and cloning in bacteria, usually E. coli. F-plasmids play a crucial role because they contain partition genes that promote the even distribution of plasmids after bacterial cell division. The bacterial artificial chromosome's usual insert size is 150–350 kbp. A similar cloning vector called a PAC has also been produced from the DNA of P1 bacteriophage.
BACs are often used to sequence the genome of organisms in genome projects, for example the Human Genome Project. A short piece of the organism's DNA is amplified as an insert in BACs, and then sequenced. Finally, the sequenced parts are rearranged in silico, resulting in the genomic sequence of the organism. BACs were replaced with faster and less laborious sequencing methods like whole genome shotgun sequencing and now more recently next-gen sequencing.
Common gene components
repE for plasmid replication and regulation of copy number.
parA and parB for partitioning F plasmid DNA to daughter cells during division and ensures stable maintenance of the BAC.
A selectable marker for antibiotic resistance; some BACs also have lacZ at the cloning site for blue/white selection.
T7 & Sp6 phage promoters for transcription of inserted genes.
Contribution to models of disease
Inherited disease
BACs are now being utilized to a greater extent in modelling genetic diseases, often alongside transgenic mice. BACs have been useful in this field as complex genes may have several regulatory sequences upstream of the encoding sequence, including various promoter sequences that will govern a gene's expression level. BACs have been used to some degree of success with mice when studying neurological diseases such as Alzheimer's disease or as in the case of aneuploidy associated with Down syndrome. There have also been instances when they have been used to study specific oncogenes associated with can
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https://en.wikipedia.org/wiki/MT-ND4L
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MT-ND4L is a gene of the mitochondrial genome coding for the NADH-ubiquinone oxidoreductase chain 4L (ND4L) protein. The ND4L protein is a subunit of NADH dehydrogenase (ubiquinone), which is located in the mitochondrial inner membrane and is the largest of the five complexes of the electron transport chain. Variants of human MT-ND4L are associated with increased BMI in adults and Leber's Hereditary Optic Neuropathy (LHON).
Structure
The MT-ND4L gene is located in human mitochondrial DNA from base pair 10,469 to 10,765. The MT-ND4L gene produces an 11 kDa protein composed of 98 amino acids. MT-ND4L is one of seven mitochondrial genes encoding subunits of the enzyme NADH dehydrogenase (ubiquinone), together with MT-ND1, MT-ND2, MT-ND3, MT-ND4, MT-ND5, and MT-ND6. Also known as Complex I, this enzyme is the largest of the respiratory complexes. The structure is L-shaped with a long, hydrophobic transmembrane domain and a hydrophilic domain for the peripheral arm that includes all the known redox centres and the NADH binding site. MT-ND4L and the rest of the mitochondrially encoded subunits are the most hydrophobic of the subunits of Complex I and form the core of the transmembrane region.
An unusual feature of the human MT-ND4L gene is the 7-nucleotide gene overlap of its last three codons (5'-CAA TGC TAA-3' coding for Gln, Cys and Stop) with the first three codons of the MT-ND4 gene (5'-ATG CTA AAA-3' coding for amino acids Met-Leu-Lys). With respect to the MT-ND4L reading frame (+1), the MT-ND4 gene starts in the +3 reading frame: [CAA][TGC][TAA]AA versus CA[ATG][CTA][AAA].
Function
The MT-ND4L product is a subunit of the respiratory chain Complex I that is believed to belong to the minimal assembly of core proteins required to catalyze NADH dehydrogenation and electron transfer to ubiquinone (coenzyme Q10). Initially, NADH binds to Complex I and transfers two electrons to the isoalloxazine ring of the flavin mononucleotide (FMN) prosthetic arm to form FMNH2.
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https://en.wikipedia.org/wiki/Surround%20suppression
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Surround suppression is where the relative firing rate of a neuron may under certain conditions decrease when a particular stimulus is enlarged. It has been observed in electrophysiology studies of the brain and has been noted in many sensory neurons, most notably in the early visual system. Surround suppression is defined as a reduction in the activity of a neuron in response to a stimulus outside its classical receptive field.
The necessary functional connections with other neurons influenced by stimulation outside a particular area and by dynamic processes in general, and the absence of a theoretical description of a system state to be treated as a baseline, deprive the term "classical receptive field" of functional meaning. The descriptor "surround suppression" suffers from a similar problem, as the activities of neurons in the "surround" of the "classical receptive field are similarly determined by connectivities and processes involving neurons beyond it.) This nonlinear effect is one of many that reveals the complexity of biological sensory systems, and the connections of properties of neurons that may cause this effect (or its opposite) are still being studied. The characteristics, mechanisms, and perceptual consequences of this phenomenon are of interest to many communities, including neurobiology, computational neuroscience, psychology, and computer vision.
Background
The classical model of early vision presumes that each neuron responds independently to a specific stimulus in a localized area of the visual field. (According to Carandini et al (2005), this computational model, which may be fit to various datasets, "degrade[s] quickly if we change almost any aspect of the test stimulus.") The stimulus and corresponding location in the visual field are collectively called the classical receptive field. However, not all effects can be explained by via ad hoc independent filters. Surround suppression is one of an infinite number of possible effects in which
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https://en.wikipedia.org/wiki/Pattern%20language%20%28formal%20languages%29
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In theoretical computer science, a pattern language is a formal language that can be defined as the set of all particular instances of a string of constants and variables. Pattern Languages were introduced by Dana Angluin in the context of machine learning.
Definition
Given a finite set Σ of constant symbols and a countable set X of variable symbols disjoint from Σ, a pattern is a finite non-empty string of symbols from Σ∪X.
The length of a pattern p, denoted by |p|, is just the number of its symbols.
The set of all patterns containing exactly n distinct variables (each of which may occur several times) is denoted by Pn, the set of all patterns at all by P*.
A substitution is a mapping f: P* → P* such that
f is a homomorphism with respect to string concatenation (⋅), formally: ∀p,q∈P*. f(p⋅q) = f(p)⋅f(q);
f is non-erasing, formally: ∀p∈P*. f(p) ≠ ε, where ε denotes the empty string; and
f respects constants, formally: ∀s∈Σ. f(s) = s.
If p = f(q) for some patterns p, q ∈ P* and some substitution f, then p is said to be less general than q, written p≤q;
in that case, necessarily |p| ≥ |q| holds.
For a pattern p, its language is defined as the set of all less general patterns that are built from constants only, formally: L(p) = { s ∈ Σ+ : s ≤ p }, where Σ+ denotes the set of all finite non-empty strings of symbols from Σ.
For example, using the constants Σ = { 0, 1 } and the variables X = { x, y, z, ... }, the pattern 0x10xx1 ∈P1 and xxy ∈P2 has length 7 and 3, respectively.
An instance of the former pattern is 00z100z0z1 and 01z101z1z1, it is obtained by the substitution that maps x to 0z and to 1z, respectively, and each other symbol to itself. Both 00z100z0z1 and 01z101z1z1 are also instances of xxy. In fact, L(0x10xx1) is a subset of L(xxy). The language of the pattern x0 and x1 is the set of all bit strings which denote an even and odd binary number, respectively. The language of xx is the set of all strings obtainable by concatenating a bit string with itse
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https://en.wikipedia.org/wiki/M%C3%B6ssbauer%20effect
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The Mössbauer effect, or recoilless nuclear resonance fluorescence, is a physical phenomenon discovered by Rudolf Mössbauer in 1958. It involves the resonant and recoil-free emission and absorption of gamma radiation by atomic nuclei bound in a solid. Its main application is in Mössbauer spectroscopy.
In the Mössbauer effect, a narrow resonance for nuclear gamma emission and absorption results from the momentum of recoil being delivered to a surrounding crystal lattice rather than to the emitting or absorbing nucleus alone. When this occurs, no gamma energy is lost to the kinetic energy of recoiling nuclei at either the emitting or absorbing end of a gamma transition: emission and absorption occur at the same energy, resulting in strong, resonant absorption.
History
The emission and absorption of X-rays by gases had been observed previously, and it was expected that a similar phenomenon would be found for gamma rays, which are created by nuclear transitions (as opposed to X-rays, which are typically produced by electronic transitions). However, attempts to observe nuclear resonance produced by gamma-rays in gases failed due to energy being lost to recoil, preventing resonance (the Doppler effect also broadens the gamma-ray spectrum). Mössbauer was able to observe resonance in nuclei of solid iridium, which raised the question of why gamma-ray resonance was possible in solids, but not in gases. Mössbauer proposed that, for the case of atoms bound into a solid, under certain circumstances a fraction of the nuclear events could occur essentially without recoil. He attributed the observed resonance to this recoil-free fraction of nuclear events.
The Mössbauer effect was one of the last major discoveries in physics to be originally reported in the German language. The first reports in English were a pair of letters describing independent repetitions of the experiment.
The discovery was rewarded with the Nobel Prize in Physics in 1961 together with Robert Hofstadte
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https://en.wikipedia.org/wiki/Woobi
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Woobi, formally known as TokenAds, was a digital marketing company based in Tel Aviv, Israel. It provided in-game advertising services for online games, including supply-side platforms and real-time bidding. The company's technology monetized non-paying users through value-exchange advertising, integrated into gameplay.
History
Woobi was founded in 2009 under the name TokenAds. Its first product was a monetization solution for Facebook Apps before it began to produce technologies that allowed in-game advertising, monetizing free-to-play games using targeted advertising.
In 2009, TokenAds launched a concept to enable local brands to advertise to local audiences, and to provide real-time optimization based on game traits. In 2011, it moved away from integrating ad formats into payment sections in favor of integrating them into gameplay.
Later, Woobi launched its cross-game tracking technology aimed at improving user targeting capabilities. This led to its investment in developing wider user-profiling technologies and the release of its cross-data, profiling-based platform in 2013.
In 2014, the company submitted a patent for its Dynamic Mindset Advertising (DMA) technology, which was based on an algorithm integrated into free-to-play game loops and the user's gameplay. The DMA-based monetization technology attempted to identify moments where a user was more receptive to engage with brands before their ads were displayed.
Between the opportunities in online advertising and its own shift towards branded video advertising strategies, Woobi launched its own supply-side platform and real-time bidding exchange in 2016. The company also used its own buyer-side platform to serve as a gateway to online games for brand advertisers.
Between 2014 and 2016, Woobi opened offices in London and New York City. In September 2014, TokenAds rebranded as Woobi.
In May 2020, Woobi as well as its official website shut down all operations.
Awards and nominations
In 2017, Woobi saw r
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https://en.wikipedia.org/wiki/Zinc%20finger%20protein%20394
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Zinc finger protein 394 is a protein that in humans is encoded by the ZNF394 gene.
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https://en.wikipedia.org/wiki/Principia%20%28alga%29
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Principia is a genus of alga that has been placed in the coralline stem group on the basis of its slightly differentiated thallus; it forms an "intermediate" between Hortonella, Neoprincipia and Archaeolithophyllum.
Fossil algae
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https://en.wikipedia.org/wiki/List%20of%20medicine%20awards
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This list of medicine awards is an index to articles about notable awards for contributions to medicine, the science and practice of establishing the diagnosis, prognosis, treatment, and prevention of disease. The list is organized by region and country of the organization giving the award, but the awards may be available to people from around the world.
International
Americas
Asia
Europe
United Kingdom
Oceania
See also
Lists of awards
Lists of science and technology awards
List of biomedical science awards
List of psychology awards
Competitions and prizes in biotechnology
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https://en.wikipedia.org/wiki/Rank-into-rank
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In set theory, a branch of mathematics, a rank-into-rank embedding is a large cardinal property defined by one of the following four axioms given in order of increasing consistency strength. (A set of rank < λ is one of the elements of the set Vλ of the von Neumann hierarchy.)
Axiom I3: There is a nontrivial elementary embedding of Vλ into itself.
Axiom I2: There is a nontrivial elementary embedding of V into a transitive class M that includes Vλ where λ is the first fixed point above the critical point.
Axiom I1: There is a nontrivial elementary embedding of Vλ+1 into itself.
Axiom I0: There is a nontrivial elementary embedding of L(Vλ+1) into itself with critical point below λ.
These are essentially the strongest known large cardinal axioms not known to be inconsistent in ZFC; the axiom for Reinhardt cardinals is stronger, but is not consistent with the axiom of choice.
If j is the elementary embedding mentioned in one of these axioms and κ is its critical point, then λ is the limit of as n goes to ω. More generally, if the axiom of choice holds, it is provable that if there is a nontrivial elementary embedding of Vα into itself then α is either a limit ordinal of cofinality ω or the successor of such an ordinal.
The axioms I0, I1, I2, and I3 were at first suspected to be inconsistent (in ZFC) as it was thought possible that Kunen's inconsistency theorem that Reinhardt cardinals are inconsistent with the axiom of choice could be extended to them, but this has not yet happened and they are now usually believed to be consistent.
Every I0 cardinal κ (speaking here of the critical point of j) is an I1 cardinal.
Every I1 cardinal κ (sometimes called ω-huge cardinals) is an I2 cardinal and has a stationary set of I2 cardinals below it.
Every I2 cardinal κ is an I3 cardinal and has a stationary set of I3 cardinals below it.
Every I3 cardinal κ has another I3 cardinal above it and is an n-huge cardinal for every n<ω.
Axiom I1 implies that Vλ+1 (equivalently,
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https://en.wikipedia.org/wiki/FAM63B
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FAM63B is a protein which in humans is encoded by the gene FAM63B. This gene is highly expressed in humans. The FAM63B gene is also highly conserved throughout evolutionary history. The discovered function of FAM63B is an interaction with the kinesin-1 light chain and the transportation of vaccinia virus from the nucleus to the cell periphery.
Gene
Locus
FAM63B is located at 15q21.3-q22.1, spanning 90,707 base pairs on chromosome 15.
Alternative Names
The full name of FAM63B is family with sequence similarity 63, member B. FAM63B is also listed by its alias, KIAA1164, in some publications.
mRNA
Isoforms
The FAM63B gene encodes a primary transcript that can be alternatively spliced into 9 protein variants. FAM63B variant a is the most common isoform found in humans.
Protein
Structure
Primary Structure
FAM63B is a member of the Pfam super family, and contains a domain of unknown function (DUF544) that is homologous within the protein family. FAM63B protein variant an also contains a bipartite tryptophan binding motif from W476 to W533. Variant a of the protein also contains a hydrophobic stretch of alanine from 567 to 574 and a mixed charge sequence from residue 598 to 617. FAM63B protein may contain a signal sequence specifying return to the endoplasmic reticulum (KDEL) from residue 607 to 621 in variant a.
Secondary Structure
The secondary structure of FAM63B is a combination of coils, some α-helices, and few β-sheets. The Phyre 2 program predicts α-helices in 23% of the protein, β-strands in 9% of the protein, and the remaining 59% of the protein as disordered. The disordered regions coincide with the coiled regions predicted by other programs, and this results in the long stretch of coiled protein beginning at the N-terminus. According to the SOUSI program, there is a 16-amino acid-long span from residues 265 to 280 of FAM63B that could be a transmembrane sequence. However, transmembrane sequences generally need to be at least 20 amino acids long in
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https://en.wikipedia.org/wiki/Pu%27s%20inequality
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In differential geometry, Pu's inequality, proved by Pao Ming Pu, relates the area of an arbitrary Riemannian surface homeomorphic to the real projective plane with the lengths of the closed curves contained in it.
Statement
A student of Charles Loewner, Pu proved in his 1950 thesis that every Riemannian surface homeomorphic to the real projective plane satisfies the inequality
where is the systole of .
The equality is attained precisely when the metric has constant Gaussian curvature.
In other words, if all noncontractible loops in have length at least , then and the equality holds if and only if is obtained from a Euclidean sphere of radius by identifying each point with its antipodal.
Pu's paper also stated for the first time Loewner's inequality, a similar result for Riemannian metrics on the torus.
Proof
Pu's original proof relies on the uniformization theorem and employs an averaging argument, as follows.
By uniformization, the Riemannian surface is conformally diffeomorphic to a round projective plane. This means that we may assume that the surface is obtained from the Euclidean unit sphere by identifying antipodal points, and the Riemannian length element at each point is
where is the Euclidean length element and the function , called the conformal factor, satisfies .
More precisely, the universal cover of is , a loop is noncontractible if and only if its lift goes from one point to its opposite, and the length of each curve is
Subject to the restriction that each of these lengths is at least , we want to find an that minimizes the
where is the upper half of the sphere.
A key observation is that if we average several different that satisfy the length restriction and have the same area , then we obtain a better conformal factor , that also satisfies the length restriction and has
and the inequality is strict unless the functions are equal.
A way to improve any non-constant is to obtain the different functions from usin
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https://en.wikipedia.org/wiki/William%20Beutenmuller
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William Beutenmuller (March 31, 1864 - February 24, 1934), was an American entomologist who served as curator of entomology at the American Museum of Natural History (1888-1912), editor of the Journal of the New York Entomological Society (1893-1903), and president of the New York Entomological Society (1900). He published numerous scientific articles on many insect groups, including beetles, flies, gall wasps, and butterflies and moths.
Beutenmuller was born in Hoboken, New Jersey, and attended school in New York. He was married to scientific illustrator Edna Hyatt. He lived his later years in Tenafly, New Jersey, and died of heart disease at Englewood Hospital in 1934.
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https://en.wikipedia.org/wiki/Dephosphorylation
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In biochemistry, dephosphorylation is the removal of a phosphate (PO43−) group from an organic compound by hydrolysis. It is a reversible post-translational modification. Dephosphorylation and its counterpart, phosphorylation, activate and deactivate enzymes by detaching or attaching phosphoric esters and anhydrides. A notable occurrence of dephosphorylation is the conversion of ATP to ADP and inorganic phosphate.
Dephosphorylation employs a type of hydrolytic enzyme, or hydrolase, which cleaves ester bonds. The prominent hydrolase subclass used in dephosphorylation is phosphatase, which removes phosphate groups by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl (-OH) group.
The reversible phosphorylation-dephosphorylation reaction occurs in every physiological process, making proper function of protein phosphatases necessary for organism viability. Because protein dephosphorylation is a key process involved in cell signalling, protein phosphatases are implicated in conditions such as cardiac disease, diabetes, and Alzheimer's disease.
History
The discovery of dephosphorylation came from a series of experiments examining the enzyme phosphorylase isolated from rabbit skeletal muscle. In 1955, Edwin Krebs and Edmond Fischer used radiolabeled ATP to determine that phosphate is added to the serine residue of phosphorylase to convert it from its b to a form via phosphorylation. Subsequently, Krebs and Fischer showed that this phosphorylation is part of a kinase cascade. Finally, after purifying the phosphorylated form of the enzyme, phosphorylase a, from rabbit liver, ion exchange chromatography was used to identify phosphoprotein phosphatase I and II.
Since the discovery of these dephosphorylating proteins, the reversible nature of phosphorylation and dephosphorylation has been associated with a broad range of functional proteins, primarily enzymatic, but also including nonenzymatic proteins. Edwin Krebs and Edmond F
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https://en.wikipedia.org/wiki/Coproporphyrinogen%20III%20oxidase
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Coproporphyrinogen-III oxidase, mitochondrial (abbreviated as CPOX) is an enzyme that in humans is encoded by the CPOX gene. A genetic defect in the enzyme results in a reduced production of heme in animals. The medical condition associated with this enzyme defect is called hereditary coproporphyria.
CPOX, the sixth enzyme of the haem biosynthetic pathway, converts coproporphyrinogen III to protoporphyrinogen IX through two sequential steps of oxidative decarboxylation. The activity of the CPOX enzyme, located in the mitochondrial membrane, is measured in lymphocytes.
Function
CPOX is an enzyme involved in the sixth step of porphyrin metabolism it catalyses the oxidative decarboxylation of coproporphyrinogen III to proto-porphyrinogen IX in the haem and chlorophyll biosynthetic pathways. The protein is a homodimer containing two internally bound iron atoms per molecule of native protein. The enzyme is active in the presence of molecular oxygen that acts as an electron acceptor. The enzyme is widely distributed having been found in a variety of eukaryotic and prokaryotic sources.
Structure
Gene
Human CPOX is a mitochondrial enzyme encoded by a 14 kb CPOX gene containing seven exons located on chromosome 3 at q11.2.
Protein
CPOX is expressed as a 40 kDa precursor and contains an amino terminal mitochondrial targeting signal. After proteolytic processing, the protein is present as a mature form of a homodimer with a molecular mass of 37 kDa.
Clinical significance
Hereditary coproporphyria (HCP) and harderoporphyria are two phenotypically separate disorders that concern partial deficiency of CPOX. Neurovisceral symptomatology predominates in HCP. Additionally, it may be associated with abdominal pain and/or skin photosensitivity. Hyper-excretion of coproporphyrin III in urine and faeces has been recorded in biochemical tests. HCP is an autosomal dominant inherited disorder, whereas harderoporphyria is a rare erythropoietic variant form of HCP and is inherited in
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https://en.wikipedia.org/wiki/Aleste
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is a vertically scrolling shooter developed by Compile, originally published by Sega in 1988 for the Master System and then by CP Communications for the MSX2. The Master System version was released outside Japan as Power Strike. The game spawned the Aleste and Power Strike franchises.
Plot
The story of Aleste concerns the manmade supercomputer DIA 51, which has been infected by a hybrid virus that is spreading like wildfire, eventually leading DIA 51 to eliminate the human race. When Yuri, Ray's girlfriend, gets injured in DIA's assault, Raymond Waizen has all the reason in the world to get rid of DIA 51 once and for all in his Aleste fighter.
Releases
The game was originally released for the Master System in February 1988. This version was released outside Japan, as Power Strike. The US release was initially a mail-only limited edition, however it did later see some retail distribution at Toys R' Us and other chains in North America. The European release was a regular retail package.
An MSX2 version was released in July of that year, featuring two new stages, lowered difficulty, and a series of cutscenes.
A version of the game has been released on phones by Square Enix, presumably based on the MSX2 version. The MSX2 version has been re-released on Nintendo's Wii Virtual Console service in Japan. It along with Aleste 2 had also been rereleased through the now-defunct WOOMB service.
Reception
The Master System version called Power Strike received positive reviews. Computer and Video Games scored it 86% in 1989. Console XS scored it 90% in 1992.
Aleste series
Aleste was followed by several sequels:
Aleste Gaiden (MSX2, 1989)
Aleste 2 (MSX2, 1989)
Musha Aleste (Mega Drive, 1990)
GG Aleste (Game Gear, 1991)
Super Aleste (SNES, 1992)
Dennin Aleste (Mega-CD, 1992)
GG Aleste II (Game Gear, 1993)
GG Aleste 3 (Game Gear Micro, 2020)
Senjin Aleste (Arcade, 2021)
Aleste Branch (TBA)
Cancelled games
Dennin Aleste 2 (Mega-CD, cancelled)
Related games
There
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https://en.wikipedia.org/wiki/Bundle%20theorem
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In Euclidean geometry, the bundle theorem is a statement about six circles and eight points in the Euclidean plane. In general incidence geometry, it is a similar property that a Möbius plane may or may not satisfy. According to Kahn's Theorem, it is fulfilled by "ovoidal" Möbius planes only; thus, it is the analog for Möbius planes of Desargues' Theorem for projective planes.
Bundle theorem. If for eight different points five of the six quadruples are concyclic (contained in a cycle) on at least four cycles , then the sixth quadruple is also concyclic.
The bundle theorem should not be confused with Miquel's theorem.
An ovoidal Möbius plane in real Euclidean space may be considered as the geometry of the plane sections of an egglike surface, like a sphere, or an ellipsoid, or half a sphere glued to a suitable half of an ellipsoid, or the surface with equation , etc. If the egglike surface is a sphere one gets the space model of the classical real Möbius plane, which is the "circle geometry" on the sphere.
The essential property of an ovoidal Möbius plane is the existence of a space model via an ovoid. An ovoid in a 3-dimensional projective space is a set of points, which a) is intersected by lines in 0, 1, or 2 points and b) its tangents at an arbitrary point covers a plane (tangent plane). The geometry of an ovoid in projective 3-space is a Möbius plane, called an ovoidal Möbius plane. The point set of the geometry consists of the points of the ovoid and the curves ("cycles") are the plane sections of the ovoid. A suitable stereographical projection shows that for any ovoidal Möbius plane there exists a plane model. In the classical case the plane model is the geometry of the circles and lines (where each line is completed by a point at infinity). The bundle theorem has a planar and a spatial interpretation. In the planar model there may be lines involved. The proof of the bundle theorem is performed within the spatial model.
Theorem. The bundle theorem h
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https://en.wikipedia.org/wiki/22R-Hydroxycholesterol
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22R-Hydroxycholesterol, or (3β)-cholest-5-ene-3,22-diol is an endogenous, metabolic intermediate in the biosynthesis of the steroid hormones from cholesterol. Cholesterol ((3β)-cholest-5-en-3-ol) is hydroxylated by cholesterol side-chain cleavage enzyme (P450scc) to form 22R-hydroxycholesterol, which is subsequently hydroxylated again by P450scc to form 20α,22R-dihydroxycholesterol, and finally the bond between carbons 20 and 22 is cleaved by P450scc to form pregnenolone ((3β)-3-hydroxypregn-5-en-20-one), the precursor to the steroid hormones.
It is an agonist of the liver X receptor.
See also
20α,22R-Dihydroxycholesterol
27-Hydroxycholesterol
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https://en.wikipedia.org/wiki/Javelin%20argument
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The javelin argument, credited to Lucretius, is an ancient logical argument that the universe, or cosmological space, must be infinite. The javelin argument was used to support the Epicurean thesis about the universe. It was also constructed to counter the Aristotelian view that the universe is finite.
Overview
Lucretius introduced the concept of the javelin argument in his discourse of space and how it can be bound. He explained:
For whatever bounds it, that thing must itself be bounded likewise; and to this bounding thing there must be a bound again, and so on for ever and ever throughout all immensity. Suppose, however, for a moment, all existing space to be bounded, and that a man runs forward to the uttermost borders, and stands upon the last verge of things, and then hurls forward a winged javelin,— suppose you that the dart, when hurled by the vivid force, shall take its way to the point the darter aimed at, or that something will take its stand in the path of its flight, and arrest it? For one or other of these things must happen. There is a dilemma here that you never can escape from.
The javelin argument has two implications. If the hurled javelin flew onwards unhindered, it meant that the man running was not at the edge of the universe because there is something beyond the edge where the weapon flew. On the other hand, if it did not, the man was still not at the edge because there must be an obstruction beyond that stopped the javelin. However, the argument assumes incorrectly that a finite universe must necessarily have a "limit" or edge. The argument fails in the case that the universe might be shaped like the surface of a hypersphere or torus. (Consider a similar fallacious argument that the Earth's surface must be infinite in area: because otherwise one could go to the Earth's edge and throw a javelin, proving that the Earth's surface continued wherever the javelin hit the ground.)
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https://en.wikipedia.org/wiki/Heat%20death%20of%20the%20universe
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The heat death of the universe (also known as the Big Chill or Big Freeze) is a hypothesis on the ultimate fate of the universe, which suggests the universe will evolve to a state of no thermodynamic free energy, and will therefore be unable to sustain processes that increase entropy. Heat death does not imply any particular absolute temperature; it only requires that temperature differences or other processes may no longer be exploited to perform work. In the language of physics, this is when the universe reaches thermodynamic equilibrium. The Heat Death theory has become the leading theory of the end of the universe in the modern age with the fewest unpredictable factors.
If the curvature of the universe is hyperbolic or flat, or if dark energy is a positive cosmological constant, the universe will continue expanding forever, and a heat death is expected to occur, with the universe cooling to approach equilibrium at a very low temperature after a very long time period.
The hypothesis of heat death stems from the ideas of Lord Kelvin who, in the 1850s, took the theory of heat as mechanical energy loss in nature (as embodied in the first two laws of thermodynamics) and extrapolated it to larger processes on a universal scale. This also allowed Kelvin to formulate the heat death paradox, which disproves an infinitely old universe.
Origins of the idea
The idea of heat death stems from the second law of thermodynamics, of which one version states that entropy tends to increase in an isolated system. From this, the hypothesis implies that if the universe lasts for a sufficient time, it will asymptotically approach a state where all energy is evenly distributed. In other words, according to this hypothesis, there is a tendency in nature towards the dissipation (energy transformation) of mechanical energy (motion) into thermal energy; hence, by extrapolation, there exists the view that, in time, the mechanical movement of the universe will run down as work is converted
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https://en.wikipedia.org/wiki/Alexander%20Braun
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Alexander Carl Heinrich Braun (10 May 1805 – 29 March 1877) was a German botanist from Regensburg, Bavaria. His research centered on the morphology of plants.
Biography
He studied botany in Heidelberg, Paris and Munich. In 1833 he began teaching botany at the Polytechnic School of Karlsruhe, staying there until 1846. Afterwards he was a professor of botany in Freiburg (from 1846), Giessen (from 1850) and at the University of Berlin (1851), where he remained until 1877. While in Berlin, he was also director of the botanical garden. In 1852, he was elected a foreign member of the Royal Swedish Academy of Sciences.
Braun is largely known for his research involving plant morphology. He accepted evolution but was a critic of Darwinism. He was a proponent of vitalism, a popular 19th-century speculative theory that claimed that a regulative force existed within living matter in order to maintain functionality. Braun made important contributions in the field of cell theory.
From his 1830s analysis of the arrangement of scales on a pine cone he was a pioneer of phyllotaxis.
In 1877 Wilhelm Philippe Schimper and Philipp Bruch named the plant genus Braunia in his honor. Also, a decorative plant known as "Braun's holly fern" (Polystichum braunii) commemorates his name.
Written works
1831: Untersuchung über die Ordnung der Schuppen an den Tannenzapfen (Investigation on the order of shapes in pine cones).
1842: Nachträgliche Mitteilungen über die Gattungen Marsilia und Pilularia (Additional releases on the genera Marsilea and Pilularia).
1851: Betrachtungen über die Erscheinung der Verjüngung in der Natur, insbesondere in der Lebens- und Bildungsgeschichte der Pflanze (Leipzig, 198 pp.) (Reflections on the phenomenon of rejuvenation in nature, particularly in the life and developmental history of the plant).
1852: Über die Richtungsverhältnisse der Saftströme in den Zellen der Characeen. (on directional conditions involving juice flow in the cell of Characeae).
1853: D
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https://en.wikipedia.org/wiki/Susan%20H.%20Lees
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Susan H. Lees is an anthropologist and human ecologist, and the former editor-in-chief of Human Ecology and American Anthropologist. She is professor emeritus of cultural anthropology at City University of New York.
Research
Lees' work focuses on political ecology and anthropology. Her early work was largely focused on irrigation and its impact on agriculture, society, and conflict and relationships between groups. Her research has also explored the impact of climate change, gentrification, and other social developments on rural fishing communities in Maine, particularly crab fishing in Deer Isle, Maine.
In 1976, she became editor of Human Ecology, following the retirement of its founder Andrew P. Vayda. She invited Daniel Bates to co-edit the journal with her.
In 2009, Lees became the editor of American Anthropologist along with Fran Mascia-Lees.
Works
ed. Against the Grain: The Vayda Tradition in Human Ecology and Ecological Anthropology. AltaMira Press. 2009.
The Political Ecology of the Water Crisis In Israel. University Press of America. 1999.
Case Studies in Human Ecology. Plenum Press. 1998.
Sociopolitical Aspects of Canal Irrigation in the Valley of Oaxaca. University of Michigan Press. 1973.
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https://en.wikipedia.org/wiki/Orion-128
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The Orion-128 () is a DIY computer designed in Soviet Union. It was featured in the Radio magazine in 1990, other materials for the computer were published until 1996. It was the last Intel 8080-based DIY computer in Russia.
Overview
The Orion-128 used the same concepts as the Specialist and had similar specifications, with both advances and flaws. It gained more popularity because it was supported by a more popular magazine. In the early 1990s the computer was produced industrially at the Livny pilot plant of machine graphics means in Oryol Oblast. Much of the software for the Orion-128 was ported by hobbyists from the Specialist and the ZX Spectrum.
Technical specifications
CPU: KR580VM80A (Intel 8080A clone) clocked at 2.5 MHz.
RAM: 128 KiB in original version, expandable to 256 KiB. A bank switching scheme was used.
ROM: 2 KiB contains monitor firmware
Video: three graphics modes with the same image resolution 384 × 256 pixels. Text can be displayed using 64 columns × 25 rows of characters. Images for the upper case Cyrillic and Latin characters in KOI-7 N2 encoding are built in the Monitor ROM. List of graphics modes includes:
monochrome mode (two color palettes available: black and green, yellow and blue)
4 color mode (each pixel has its own color, two palettes available)
16 color mode (each group of 8 horizontal pixels can use one of 16 foreground colors and one of 16 background colors)
Storage media: cassette tape, ROM drive (a special board containing a set of ROM chips). In later years a floppy disk controller and an ATA hard disk controller were developed
Keyboard: 67 keys. The keyboard matrix is attached via programmable peripheral interface chip KR580VV55 (Intel 8255 clone) and scanned by CPU
Peculiarities
"Orion" is partially compatible with "Radio-86RK" in terms of keyboard, standard ROM subroutines and data storage format on the cassette, and with another amateur radio computer, "Specialist" in terms of graphic screen format. Apparently,
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https://en.wikipedia.org/wiki/Volkensin
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Volkensin is a eukaryotic ribosome-inactivating protein found in the Adenia volkensii plant. It is a glycoprotein with two subunits A and B. A subunit is linked to B subunit with disulfide bridges and non-covalent bonds. B subunit is responsible for binding to the galactosyl-terminated receptors on the cell membrane that allows the entry the A subunit of the toxin into the cell, which performs the inhibitory function. Volkensin is a galactose specific lectin that can inhibit protein synthesis in whole cells and in cell-free lysates. This protein can be included into the category of risin like toxins and it resembles modeccin, the toxin of Adenia digitata. Although very similar in composition, volkensin contains more cysteine residues and more than twice as much sugar than modeccin, due to high content of galactose and mannose. In addition, volkensin is able to inhibit protein synthesis at concentrations 10 times lower than required for modeccin. From gene sequencing analysis, volkensin was found to be coded by 1569-bp ORF, that is 523 amino acid residues without introns. The internal linker sequence is 45 bp. The active site of the A subunit contains Ser203, a novel residue that is conserved in all ribosome inactivating proteins.
The toxin can be isolated via affinity chromatography, using acid-treated Sepharose 6B.
Volkensin, and toxins alike are studied to understand protein entry into the cell and many have been found to have antitumor applicability. Rats that have been administered a high dose of volkensin died between 7 and 12 hours. For 1–2 hours after poisoning, rats behaved normally and then became sedated until death with short-lasting seizures. Rats that have been administered lower doses died within several days and showed wax-like peritoneal fat, which indicated the formation of a pancreatic lesion.
In addition, volkensin has been also found to agglutinate red blood cells without any specificity for a particular blood group. This is likely due to its
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https://en.wikipedia.org/wiki/Grain%20damage
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Grain damage is any degradation in the quality of grain. In the current grain trade, this damage can affect price, feed quality, food product quality, and susceptibility to pest contamination. Between the field and the end use, grain may go through any number of handling operations which can each contribute to grain damage. For example, grain might encounter free fall, conveyors, spouts, grain throwers, elevators, hoppers, dryers, and many more. Overall, these handling methods can be evaluated as to what effect they have on the grain. Damaged grain can often be characterized by the extent to which it reduces storage time. For example, cracked or broken kernels are more susceptible to insect or bacteria as well as chemical degradation. The damage to the actual grain is only one example of losses incurred after harvest. In order to quantify grain damage, one must also understand grain quality. Grain quality is a very broad term and can relate to many topics such as foreign material, chemical compositions, mechanical damage, insect infestations, and many more. These references to quality are highly dependent on the end use of the grain. Certain types of damage may be acceptable to specific industries, whereas others cannot use grain with these issues.
Defining Grain Damage
Grain damage is such a broad term that it can be difficult to pinpoint all factors that can be considered damage. In addition, these factors are not easily measured. Many common methods for determining grain damage levels include some type of visible inspection, which can carry with it a large amount of error. The United States Department of Agriculture, USDA, has for many years listed standards for many types of grains. In those standards, they have identified a normalized grading scale based on factors such as test weight and limits of damaged kernels and foreign material. Throughout these standards, the definitions listed for damage can be open to interpretation by the person evaluating the grain
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https://en.wikipedia.org/wiki/Phase%20distinction
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Phase Distinction is a property of programming languages that observe a strict division between types and terms. A concise rule for determining whether phase distinction is preserved in a language or not has been proposed by Luca Cardelli - If A is a compile-time term and B is a subterm of A, then B must also be a compile-time term.
Most statically typed languages conform to the principle of phase distinction. However, some languages with especially flexible and expressive type systems (notably dependently typed programming languages) allow types to be manipulated in the same ways as regular terms. They may be passed to functions or returned as results.
A language with phase distinction may have separate namespaces for types and run-time variables. In an optimizing compiler, phase distinction marks the boundary between expressions which are safe to erase.
Theory
Phase distinction is used in conjunction with static checking. By using a calculus based system, phase distinction removes the need to enforce linear logic between different types and terms of programming.
Introduction
Phase Distinction distinguishes between processing to be done at compile-time versus processing done at runtime.
Consider a simple language, with terms:
t ::= true | false | x | λx : T . t | t t | if t then t else t
and types:
T ::= Bool | T -> T
Note how types and terms are distinct. At compile time, types are used to verify the validity of the terms. However, types do not play any role at runtime.
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https://en.wikipedia.org/wiki/Little%20brown%20bat
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The little brown bat or little brown myotis (Myotis lucifugus) is an endangered species of mouse-eared microbat found in North America. It has a small body size and glossy brown fur. It is similar in appearance to several other mouse-eared bats, including the Indiana bat, northern long-eared bat, and Arizona myotis, to which it is closely related. Despite its name, the little brown bat is not closely related to the big brown bat, which belongs to a different genus.
Its mating system is polygynandrous, or promiscuous, and females give birth to one offspring annually. The offspring, called pups, are quickly weaned and reach adult size in some dimensions by three weeks old. The little brown bat has a mean lifespan of 6.5 years, though one individual in the wild reached 34 years old. It is nocturnal, foraging for its insect prey at night and roosting in hollow trees or buildings during the day, among less common roost types. It navigates and locates prey with echolocation.
It has few natural predators, but may be killed by raptors such as owls, as well as terrestrial predators such as raccoons. Other sources of mortality include diseases such as rabies and white-nose syndrome. White-nose syndrome has been a significant cause of mortality since 2006, killing over one million little brown bats by 2011. In the Northeastern United States, population loss has been extreme, with surveyed hibernacula (caves used for hibernation) averaging a population loss of 90%.
Humans frequently encounter the little brown bat due to its habit of roosting in buildings. Colonies in buildings are often considered pests because of the production of waste or the concern of rabies transmission. Little brown bats rarely test positive for rabies, however. Some people attempt to attract little brown bats to their property, but not their houses, by installing bat houses.
Taxonomy
{{cladogram|align=left|style=width:275px;font-size:85%;line-height:85%|caption=Relationships of Nearctic Myotis specie
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https://en.wikipedia.org/wiki/Circe%20effect
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The Circe effect is a phenomenon proposed by William Jencks seen in chemistry and biochemistry where in order to speed up a reaction, the ground state of the substrate is destabilized by an enzyme.
Mechanism
Highly favourable binding of a substrate at a non-reactive site will force the reactive site of the substrate to be more reactive by putting it in a very unfavourable position. This effect was observed in orotidine 5‘-phosphate decarboxylase. This can occur by positioning a charged amino acid group next to the charged substrate thus destabilizing it, thus making the reaction occur faster. Furthermore, the substrate is put into an optimal position by the enzyme for the reaction to occur, thus decreasing the entropy greatly.
A corollary of the effect is to explain the existence of one-way enzymes that are much more effective catalysts for one direction of reaction than the other. For example, the limiting rate in the forward direction of the reaction catalyzed by methionine adenosyltransferase is about 2 × 105 times higher than it is for the reverse reaction. This concept is frequently misunderstood: it does not imply any violation of thermodynamic principles. It is a kinetic effect, not a thermodynamic one, and the reaction always proceeds toward equilibrium, regardless of where the process starts. And when it is at equilibrium the rate is always zero.
Etymology
This process was named after Circe in Homer's Odyssey, who lured men and turned them into pigs.
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https://en.wikipedia.org/wiki/Eva%20Jablonka
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Eva Jablonka () (born 1952) is an Israeli evolutionary theorist and geneticist, known especially for her interest in epigenetic inheritance. Born in 1952 in Poland, she emigrated to Israel in 1957. She is a professor at the Cohn Institute for the History of Philosophy of Science and Ideas at Tel Aviv University. In 1981 she was awarded the Landau prize of Israel for outstanding Master of Science (M.Sc.) work and in 1988, the Marcus prize for outstanding Ph.D. work. She is a proponent of academic freedom, recognising that on such matters, "academic and political issues cannot really be kept apart", although she is not a proponent of simplistic solutions, and shows a preference to describe her own position.
Work on evolutionary themes
Jablonka publishes about evolutionary themes, especially epigenetics. Her emphasis on non-genetic forms of evolution has received interest from those attempting to expand the scope of evolutionist thinking into other spheres. Jablonka has been described as being in the vanguard of an ongoing revolution within evolutionary biology, and is a leading proponent of the extended evolutionary synthesis.
Her first book on the subject of epigenetics, Epigenetic Inheritance and Evolution: the Lamarckian Dimension (1995), was co-authored with Marion Lamb. Her book Animal Traditions (2000), co-authored with Eytan Avital, extended models of human cultural transmission to the non-human animal world, to show that cultural evolution has played an important role in the evolution of other animals. Jablonka again co-authored with Lamb on Evolution in Four Dimensions (2005). Building on the approach of evolutionary developmental biology, and recent findings of molecular and behavioral biology, they argue the case for the transmission of not just genes per se, but heritable variations transmitted from generation to generation by whatever means. They suggest that such variation can occur at four levels. Firstly, at the established physical level of genetic
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https://en.wikipedia.org/wiki/Newlyn%20Tidal%20Observatory
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Newlyn Tidal Observatory is a grade II listed tide gauge hut on the South Pier in Newlyn, Cornwall. Measurements of sea level taken at the observatory between 1915 and 1921 were used to define the reference level, Ordnance Datum Newlyn, for height measurement on the British mainland. The tide gauge has collected over 100 years of observations which has significantly contributed to studies in sea level science.
Building and location
The observatory is a building situated behind the lighthouse at the end of the South Pier in Newlyn, near Penzance, in Cornwall. Constructed of concrete, it has the appearance of a small hut and is painted in red and white stripes. Inside the building is an Ordnance Survey benchmark, constituted of a brass bolt (OSBM 4676 2855), and a 1.6m diameter stilling well set into the pier which has ocean access via an inlet.
History
The Ordnance Survey established the observatory in 1915 to contribute to the measurement of a national vertical datum defined by mean sea level. The subsequent 6-year measurement campaign at the observatory, conducted from 1 May 1915 to 30 April 1921, determined the value of mean sea level as 4.751 m below the level of the brass bolt benchmark inside the hut. Due to the stable underlying granite bedrock, the proximity to the open ocean, and the absence of rivers, the observations at Newlyn were selected as the basis, or ordnance datum, for elevation measurements across Great Britain. To realise the reference datum across the country, in the early twentieth century spirit levelling techniques were used to measure a national network of circa 200 fundamental benchmarks, all referenced to the Newlyn brass bolt.
From 1915 to 1983 the observatory measured sea level using a float in the stilling well, along with a gauge supplied by Cary and Porter. With advances in technology, an Aanderaa pressure gauge was installed in 1981 to operate alongside the well gauge. From 1983 onwards, the primary sensor has been a b
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https://en.wikipedia.org/wiki/Trunk%20neural%20crest
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The trunk neural crest or truncal neural crest is one of the regions of neural crest in the embryo.
The trunk neural crest lies between the vagal and sacral neural crest and gives rise to two groups of cells. One group migrates dorsolateral and populates the skin, forming pigment cells and the other migrates ventrolateral through the anterior sclerotome to become the epinephrine-producing cells of the adrenal gland and the neurons of the sympathetic nervous system. Some cells remain in the sclerotome to form the dorsal root ganglia
Other Migration Locations:
Proximal to the spinal cord and line up symmetrically to form the dorsal root ganglia.
Into the skin to form melanocytes.
Chromaffin cells of the adrenal medulla.
Near the vertebral column and become sympathetic chain ganglia.
Differentiation involves BMP/noggin.
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https://en.wikipedia.org/wiki/Particle%20decay
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In particle physics, particle decay is the spontaneous process of one unstable subatomic particle transforming into multiple other particles. The particles created in this process (the final state) must each be less massive than the original, although the total mass of the system must be conserved. A particle is unstable if there is at least one allowed final state that it can decay into. Unstable particles will often have multiple ways of decaying, each with its own associated probability. Decays are mediated by one or several fundamental forces. The particles in the final state may themselves be unstable and subject to further decay.
The term is typically distinct from radioactive decay, in which an unstable atomic nucleus is transformed into a lighter nucleus accompanied by the emission of particles or radiation, although the two are conceptually similar and are often described using the same terminology.
Probability of survival and particle lifetime
Particle decay is a Poisson process, and hence the probability that a particle survives for time t before decaying (the survival function) is given by an exponential distribution whose time constant depends on the particle's velocity:
where
is the mean lifetime of the particle (when at rest), and
is the Lorentz factor of the particle.
Table of some elementary and composite particle lifetimes
All data are from the Particle Data Group.
{| class=wikitable style="text-align: center;"
!Type
!Name
!Symbol
!Mass (MeV)
!Mean lifetime
|-
|rowspan="3" | Lepton
|Electron / Positron
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|0.511
|
|-
|Muon / Antimuon
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|105.7
|
|-
|Tau lepton / Antitau
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|1777
|
|-
|rowspan="2" | Meson
|Neutral Pion
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|135
|
|-
|Charged Pion
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|139.6
|
|-
|rowspan="2" | Baryon
|Proton / Antiproton
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|938.2
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|-
|Neutron / Antineutron
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|939.6
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|-
|rowspan="2" | Boson
|W boson
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|80400
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|-
|Z boson
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|91000
|
|}
Decay rate
This section uses natural units, where
The lifetime of a particle is given by the inverse of its decay rate, , the
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https://en.wikipedia.org/wiki/Tego%20film
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Tego film is an adhesive sheet used in the manufacture of waterproof plywood. It is applied dry and cured by heat, which allows for high-quality laminates that are free from internal voids and warping. Tego film plywood products were used in aircraft manufacture in Germany during World War II, and the loss of the plant during a 1943 bombing raid was a serious blow to several aircraft projects. Tego film was an invention of the Essen, Germany, firm of Th. Goldschmidt AG later Evonik Industries ) .
Development and use for plywood
Tego film was developed as a glue for waterproof plywood. It comprised a paper sheet impregnated with a resole phenolic resin. heated, assembled between wood veneers and then compressed, a strong and waterproof laminated plywood was formed. Most plywood at this time used other adhesives, such as casein. These adhesives were generally applied as aqueous solutions, which caused warping of thin veneers and made achieving a solid laminate without risk of voids difficult. As Tego film was used dry, it gave a high-integrity result, solid, and without risk of hidden weaknesses. This became an important factor in time, when it was applied to use in aircraft construction.
This adhesive was manufactured by Th. Goldschmidt AG Essen at their Wuppertal subsidiary. By 1932, it was being exported worldwide.
Use for aircraft
The de Havilland Albatross airliner of 1936 had a fuselage of wooden sandwich construction; wafers of birch plywood were spaced apart by a balsa sheet and glued by a casein adhesive. This same construction, but with Aerolite, a urea-formaldehyde adhesive, achieved fame with its wartime use in the DH.98 Mosquito fast bomber. As well as being a construction of light weight and high performance, it also avoided the use of aluminium, a strategic material during wartime, and could use the skills of woodworkers, rather than those of specialised aircraft metalworkers.
When Germany attempted to emulate this aircraft with the Ta 154 Mo
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https://en.wikipedia.org/wiki/Triangle%20of%20U
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The triangle of U ( ) is a theory about the evolution and relationships among the six most commonly known members of the plant genus Brassica. The theory states that the genomes of three ancestral diploid species of Brassica combined to create three common tetraploid vegetables and oilseed crop species. It has since been confirmed by studies of DNA and proteins.
The theory is summarized by a triangular diagram that shows the three ancestral genomes, denoted by AA, BB, and CC, at the corners of the triangle, and the three derived ones, denoted by AABB, AACC, and BBCC, along its sides.
The theory was first published in 1935 by Woo Jang-choon, a Korean-Japanese botanist (writing under the Japanized name "U Nagaharu"). Woo made synthetic hybrids between the diploid and tetraploid species and examined how the chromosomes paired in the resulting triploids.
U's theory
The six species are
The code in the "Chr.count" column specifies the total number of chromosomes in each somatic cell, and how it relates to the number of chromosomes in each full genome set (which is also the number found in the pollen or ovule), and the number of chromosomes in each component genome. For example, each somatic cell of the tetraploid species Brassica napus, with letter tags AACC and count "2=4=38", contains two copies of the A genome, each with 10 chromosomes, and two copies of the C genome, each with 9 chromosomes, which is 38 chromosomes in total. That is two full genome sets (one A and one C), hence "2=38" which means "=19" (the number of chromosomes in each gamete). It is also four component genomes (two A and two C), hence "4=38".
The three diploid species exist in nature, but can easily interbreed because they are closely related. This interspecific breeding allowed for the creation of three new species of tetraploid Brassica. (Critics, however, consider the geological separation too large.) These are said to be allotetraploid (containing four genomes from two or more different
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https://en.wikipedia.org/wiki/Menger%27s%20theorem
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In the mathematical discipline of graph theory, Menger's theorem says that in a finite graph, the size of a minimum cut set is equal to the maximum number of disjoint paths that can be found between any pair of vertices.
Proved by Karl Menger in 1927, it characterizes the connectivity of a graph.
It is generalized by the max-flow min-cut theorem, which is a weighted, edge version, and which in turn is a special case of the strong duality theorem for linear programs.
Edge connectivity
The edge-connectivity version of Menger's theorem is as follows:
Let G be a finite undirected graph and x and y two distinct vertices. Then the size of the minimum edge cut for x and y (the minimum number of edges whose removal disconnects x and y) is equal to the maximum number of pairwise edge-independent paths from x to y.
Extended to all pairs: a graph is k-edge-connected (it remains connected after removing fewer than k edges) if and only if every pair of vertices has k edge-disjoint paths in between.
Vertex connectivity
The vertex-connectivity statement of Menger's theorem is as follows:
Let G be a finite undirected graph and x and y two nonadjacent vertices. Then the size of the minimum vertex cut for x and y (the minimum number of vertices, distinct from x and y, whose removal disconnects x and y) is equal to the maximum number of pairwise internally vertex-disjoint paths from x to y.
Extended to all pairs: a graph is k-vertex-connected (it has more than k vertices and it remains connected after removing fewer than k vertices) if and only if every pair of vertices has at least k internally vertex-disjoint paths in between.
All these statements (in both edge and vertex versions) remain true in directed graphs (when considering directed paths).
Short proof
Most direct proofs consider a more general statement to allow proving it by induction. It is also convenient to use definitions that include some degenerate cases.
The following proof for undirected graphs works without
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https://en.wikipedia.org/wiki/DEGS2
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Delta(4)-desaturase, sphingolipid 2 is a protein that in humans is encoded by the DEGS2 gene.
Function
This gene encodes a bifunctional enzyme that is involved in the biosynthesis of sphingolipids in human skin and in other phytosphingolipid-containing tissues. This enzyme can act as a sphingolipid delta(4)-desaturase, and also as a sphingolipid C4-hydroxylase.
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https://en.wikipedia.org/wiki/Vector%20projection
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The vector projection (also known as the vector component or vector resolution) of a vector on (or onto) a nonzero vector is the orthogonal projection of onto a straight line parallel to .
The projection of onto is often written as or .
The vector component or vector resolute of perpendicular to , sometimes also called the vector rejection of from (denoted or ), is the orthogonal projection of onto the plane (or, in general, hyperplane) that is orthogonal to . Since both and are vectors, and their sum is equal to , the rejection of from is given by:
To simplify notation, this article defines and
Thus, the vector is parallel to the vector is orthogonal to and
The projection of onto can be decomposed into a direction and a scalar magnitude by writting it as
where is a scalar, called the scalar projection of onto , and is the unit vector in the direction of . The scalar projection is defined as
where the operator ⋅ denotes a dot product, ‖a‖ is the length of , and θ is the angle between and .
The scalar projection is equal in absolute value to the length of the vector projection, with a minus sign if the direction of the projection is opposite to the direction of , that is, if the angle between the vectors is more than 90 degrees.
The vector projection can be calculated using the dot product of and as:
Notation
This article uses the convention that vectors are denoted in a bold font (e.g. ), and scalars are written in normal font (e.g. a1).
The dot product of vectors and is written as , the norm of is written ‖a‖, the angle between between and is denoted θ.
Definitions based on angle θ
Scalar projection
The scalar projection of on is a scalar equal to
where θ is the angle between and .
A scalar projection can be used as a scale factor to compute the corresponding vector projection.
Vector projection
The vector projection of on is a vector whose magnitude is the scalar projection of on with the same direction
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https://en.wikipedia.org/wiki/Ludmila%20Peterson
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Ludmila Georgievna Peterson, () – Russian educator, Doktor nauk (corresponds to a higher degree than a Ph.D.). Author of mathematical curricula for preK-Middle School students. Namely she created textbooks and workbooks:
“Playbook – Steps to school” ()
"Learn to Learn" и ()
and others
She is Chief Scientist of Center of Active Education "School 2000", () and "Perspective", () Complex of Education.
In northern spring of 2014 mathematical textbooks by Ludmila Peterson didn't pass annual state Evaluation and excluded from federally approved list of textbooks for 2014/2015. The evaluator from Russian Academy of Education stated that "It is unlikely the contents of the textbook will encourage the sense of patriotism and pride for the Country and the People".
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https://en.wikipedia.org/wiki/Dialdehyde%20starch
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Dialdehyde starch is a polysaccharide derived by chemical modification from starch. It is prepared by periodate oxidation of starch.
It has found use in the paper industry, where in it has been shown to improve the wet strength of consumer products like toilet paper and paper towels.
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https://en.wikipedia.org/wiki/Patellar%20tendon
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The patellar tendon is the distal portion of the common tendon of the quadriceps femoris, which is continued from the patella to the tibial tuberosity. It is also sometimes called the patellar ligament as it forms a bone to bone connection when the patella is fully ossified.
Structure
The patellar tendon is a strong, flat ligament, which originates on the apex of the patella distally and adjoining margins of the patella and the rough depression on its posterior surface; below, it inserts on the tuberosity of the tibia; its superficial fibers are continuous over the front of the patella with those of the tendon of the quadriceps femoris. It is about 4.5 cm long in adults (range from 3 to 6 cm).
The medial and lateral portions of the quadriceps tendon pass down on either side of the patella to be inserted into the upper extremity of the tibia on either side of the tuberosity; these portions merge into the capsule, as stated above, forming the medial and lateral patellar retinacula.
The posterior surface of the patellar tendon is separated from the synovial membrane of the joint by a large infrapatellar pad of fat, and from the tibia by a bursa.
Clinical significance
The patellar tendon can be injured in a patellar tendon rupture. Because tendon does not regenerate fully in humans, there is a significant clinical need for research into therapies for patellar tendon rupture.
It can be used as a tissue source in the repair of other ligaments. In the event of a torn anterior cruciate ligament, the patellar tendon can be used in the rehabilitation process. In this case, the middle one third of the patellar tendon is harvested and inserted through tunnels that are drilled into the femur and tibia. The portion of the patellar tendon is then drawn through these tunnels in the bone and will be affixed to the bone via screws. The recovery process takes approximately 4–6 months upon the completion of surgery. This patellar tendon method of reconstruction was traditionally
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https://en.wikipedia.org/wiki/NATO%20Star
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The NATO Star is a sculpture situated in the court of honor of the North Atlantic Treaty Organization's (NATO) headquarters in Brussels, Belgium. Unveiled in 1971, the sculpture symbolises the bond between Europe and North America, and is inspired by the organization's flag, which was introduced in 1953.
Design
History
Creation
2016 relocation
As part of the move to NATO's new headquarters, the star moved across Boulevard Leopold III to its new home on Saturday 28 May 2016. The star is surrounded by the flags of the NATO member countries.
See also
NATO headquarters
Flag of NATO
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https://en.wikipedia.org/wiki/Motorola%20Solutions
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Motorola Solutions, Inc. is an American video equipment, telecommunications equipment, software, systems and services provider that succeeded Motorola, Inc., following the spinoff of the mobile phone division into Motorola Mobility in 2011. The company is headquartered in Chicago, Illinois.
History
Motorola Solutions began trading as a separate independent company on January 4, 2011, under the NYSE symbol MSI. In April 2011, Motorola Solutions completed the sale of its cellular infrastructure business to Nokia Siemens Networks for $975 million in cash. As part of the transaction, approximately 6,900 employees were transferred to Nokia Siemens Networks. The same month, Chinese telecommunications company Huawei and Motorola Solutions settled their intellectual property disputes.
In 2012, Motorola Solutions purchased Psion for $200 million and added it to its Enterprise business. A large majority of the Enterprise business was formerly Symbol Technologies, which Motorola, Inc. had acquired in 2007. On October 27, 2014, Motorola Solutions sold its Enterprise business to Zebra Technologies for $3.45 billion in cash. As part of the sale, approximately 4,500 Motorola Solutions employees from locations throughout the world were transferred to Zebra.
In August 2015, the company received a $1 billion investment from the private equity firm Silver Lake Partners, enabling a stock buyback and providing Silver Lake with two board seats.
In December 2015, the company announced that it would acquire Airwave Solutions, the UK-based operator of the British public safety radio network servicing the police, fire, and ambulance services across England, Scotland, and Wales. The company completed the acquisition on February 19, 2016.
Beginning in March 2017, Motorola Solutions filed a series of lawsuits against China-based two-way radio manufacturer Hytera in the United States, Germany, and Australia, as well as with the United States International Trade Commission (USITC). The comp
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https://en.wikipedia.org/wiki/Gene%20drive
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A gene drive is a natural process and technology of genetic engineering that propagates a particular suite of genes throughout a population by altering the probability that a specific allele will be transmitted to offspring (instead of the Mendelian 50% probability). Gene drives can arise through a variety of mechanisms. They have been proposed to provide an effective means of genetically modifying specific populations and entire species.
The technique can employ adding, deleting, disrupting, or modifying genes.
Proposed applications include exterminating insects that carry pathogens (notably mosquitoes that transmit malaria, dengue, and zika pathogens), controlling invasive species, or eliminating herbicide or pesticide resistance.
As with any potentially powerful technique, gene drives can be misused in a variety of ways or induce unintended consequences. For example, a gene drive intended to affect only a local population might spread across an entire species. Gene drives that eradicate populations of invasive species in their non-native habitats may have consequences for the population of the species as a whole, even in its native habitat. Any accidental return of individuals of the species to its original habitats, through natural migration, environmental disruption (storms, floods, etc.), accidental human transportation, or purposeful relocation, could unintentionally drive the species to extinction if the relocated individuals carried harmful gene drives.
Gene drives can be built from many naturally occurring selfish genetic elements that use a variety of molecular mechanisms. These naturally occurring mechanisms induce similar segregation distortion in the wild, arising when alleles evolve molecular mechanisms that give them a transmission chance greater than the normal 50%.
Most gene drives have been developed in insects, notably mosquitoes, as a way to control insect-borne pathogens. Recent developments designed gene drives directly in viruses, notabl
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https://en.wikipedia.org/wiki/Handover%20keying
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In wireless technology, handover keying (Hokey) refers to maintaining a secure connection seamlessly while migrating from one wireless network to another.
External links
IETF Working Group
Interview with Russ Housley, chair of the Internet Engineering Task Force
Wireless networking
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https://en.wikipedia.org/wiki/Biotic%20potential
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Biotic potential is described by the unrestricted growth of populations resulting in the maximum growth of that population.
Biotic potential is the highest possible vital index of a species; therefore, when the species has its highest birthrate and lowest mortality rate.
Quantitative Expression
The biotic potential is the quantitative expression of the ability of a species to face natural selection in any environment. The main equilibrium of a particular population is described by the equation:
Number of Individuals = Biotic Potential/Resistance of the Environment (Biotic and Abiotic)
Chapman also relates to a "vital index", regarding a ratio to find the rate of surviving members of a species, whereas;
Vital Index = (number of births/number of deaths)*100.
Components
According to the ecologist R.N. Chapman (1928), the biotic potential could be divided into a reproductive and survival potential. The survival potential could in turn be divided into nutritive and protective potentials.
Reproductive potential (potential natality) is the upper limit to biotic potential in the absence of mortality. Survival potential is the reciprocal of mortality. Because reproductive potential does not account for the number of gametes surviving, survival potential is a necessary component of biotic potential. In the absence of mortality, biotic potential = reproductive potential.
Chapman also identified two additional components of nutritive and protective potentials as divisions of the survival potential. Nutritive potential is the ability to acquire and use food for growth and energy. Protective potential is described by the ability of the organism to protect itself against the dynamic forces of environment in order to insure successful reproduction and offspring.
Full expression of the biotic potential of an organism is restricted by environmental resistance, any condition that inhibits the increase in number of the population. It is generally only reached when environmen
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https://en.wikipedia.org/wiki/Gracility
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Gracility is slenderness, the condition of being gracile, which means slender. It derives from the Latin adjective gracilis (masculine or feminine), or gracile (neuter), which in either form means slender, and when transferred for example to discourse takes the sense of "without ornament", "simple" or various similar connotations.
In Glossary of Botanic Terms, B. D. Jackson speaks dismissively of an entry in earlier dictionary of A. A. Crozier as follows: "Gracilis (Lat.), slender. Crozier has the needless word 'gracile'". However, his objection would be hard to sustain in current usage; apart from the fact that gracile is a natural and convenient term, it is hardly a neologism. The Shorter Oxford English Dictionary gives the source date for that usage as 1623 and indicates the word is misused (through association with grace) for "gracefully slender". This misuse is unfortunate at least, because the terms gracile and grace are unrelated: the etymological root of grace is the Latin word gratia from gratus, meaning 'pleasing', and has nothing to do with slenderness or thinness.
In biology
In biology, the term is in common use, whether as English or Latin:
The term gracile—and its opposite, robust—occur in discussion of the morphology of various hominids for example.
The gracile fasciculus is a particular bundle of axon fibres in the spinal cord
The gracile nucleus is a particular structure of neurons in the medulla oblongata
"GRACILE syndrome", is associated with a BCS1L mutation
In biological taxonomy, gracile is the specific name or specific epithet for various species. Where the gender is appropriate, the form is gracilis. Examples include:
Campylobacter gracilis, a species of bacterium implicated in foodborne disease
Ctenochasma gracile, a late Jurassic pterosaur
Eriophorum gracile, a species of sedge, Cyperaceae
Euglena gracilis, a unicellular flagellate protist
Hydrophis gracilis, a species of sea snakes
Melampodium gracile, a flowering plant s
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https://en.wikipedia.org/wiki/Quasi-birth%E2%80%93death%20process
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In queueing models, a discipline within the mathematical theory of probability, the quasi-birth–death process describes a generalisation of the birth–death process. As with the birth-death process it moves up and down between levels one at a time, but the time between these transitions can have a more complicated distribution encoded in the blocks.
Discrete time
The stochastic matrix describing the Markov chain has block structure
where each of A0, A1 and A2 are matrices and A*0, A*1 and A*2 are irregular matrices for the first and second levels.
Continuous time
The transition rate matrix for a quasi-birth-death process has a tridiagonal block structure
where each of B00, B01, B10, A0, A1 and A2 are matrices. The process can be viewed as a two dimensional chain where the block structure are called levels and the intra-block structure phases. When describing the process by both level and phase it is a continuous-time Markov chain, but when considering levels only it is a semi-Markov process (as transition times are then not exponentially distributed).
Usually the blocks have finitely many phases, but models like the Jackson network can be considered as quasi-birth-death processes with infinitely (but countably) many phases.
Stationary distribution
The stationary distribution of a quasi-birth-death process can be computed using the matrix geometric method.
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https://en.wikipedia.org/wiki/MDN%20Web%20Docs
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MDN Web Docs, previously Mozilla Developer Network and formerly Mozilla Developer Center, is a documentation repository and learning resource for web developers. It was started by Mozilla in 2005 as a unified place for documentation about open web standards, Mozilla's own projects, and developer guides.
MDN Web Docs content is maintained by Mozilla, Google employees, and volunteers (community of developers and technical writers). It also contains content contributed by Microsoft, Google, and Samsung who, in 2017, announced they would shut down their own documentation projects and move all their documentation to MDN Web Docs. Topics include HTML5, JavaScript, CSS, Web APIs, Django, Node.js, WebExtensions, MathML, and others.
History
In 2005, Mozilla Corporation started the project under the name Mozilla Developer Center. Mozilla Corporation still funds servers and employs staff working on the projects.
The initial content for the website was provided by DevEdge, for which the Mozilla Foundation was granted a license by AOL. The site now contains a mix of content migrated from DevEdge and mozilla.org, as well as original and more up-to-date content. Documentation was also migrated from XULPlanet.com.
On Oct 3, 2016, Brave browser added Mozilla Developer Network as one of its default search engines options.
In 2017, MDN Web Docs became the unified documentation of web technology for Google, Samsung, Microsoft, and Mozilla. Microsoft started redirecting pages from Microsoft Developer Network to MDN.
In 2019, Mozilla started Beta testing a new reader site for MDN Web Docs written in React (instead of jQuery; some jQuery functionality was replaced with Cheerio library). The new site was launched on December 14, 2020. Since December 14, 2020, all editable content is stored in a Git repository hosted on GitHub, where contributors open pull requests and discuss changes.
On January 25 2021, the Open Web Docs (OWD) organization was launched as a non-profit fiscal entity
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https://en.wikipedia.org/wiki/Higgs%20phase
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In theoretical physics, it is often important to consider gauge theory that admits many physical phenomena and "phases", connected by phase transitions, in which the vacuum may be found.
Global symmetries in a gauge theory may be broken by the Higgs mechanism. In more general theories such as those relevant in string theory, there are often many Higgs fields that transform in different representations of the gauge group.
If they transform in the adjoint representation or a similar representation, the original gauge symmetry is typically broken to a product of U(1) factors. Because U(1) describes electromagnetism including the Coulomb field, the corresponding phase is called a Coulomb phase.
If the Higgs fields that induce the spontaneous symmetry breaking transform in other representations, the Higgs mechanism often breaks the gauge group completely and no U(1) factors are left. In this case, the corresponding vacuum expectation values describe a Higgs phase.
Using the representation of a gauge theory in terms of a D-brane, for example D4-brane combined with D0-branes, the Coulomb phase describes D0-branes that have left the D4-branes and carry their own independent U(1) symmetries. The Higgs phase describes D0-branes dissolved in the D4-branes as instantons.
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https://en.wikipedia.org/wiki/HH-suite
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The HH-suite is an open-source software package for sensitive protein sequence searching. It contains programs that can search for similar protein sequences in protein sequence databases. Sequence searches are a standard tool in modern biology with which the function of unknown proteins can be inferred from the functions of proteins with similar sequences. HHsearch and HHblits are two main programs in the package and the entry point to its search function, the latter being a faster iteration. HHpred is an online server for protein structure prediction that uses homology information from HH-suite.
The HH-suite searches for sequences using hidden Markov models (HMMs). The name comes from the fact that it performs HMM-HMM alignments. Among the most popular methods for protein sequence matching, the programs have been cited more than 5000 times total according to Google Scholar.
Background
Proteins are central players in all of life's processes. Understanding them is central to understanding molecular processes in cells. This is particularly important in order to understand the origin of diseases. But for a large fraction of the approximately 20 000 human proteins the structures and functions remain unknown. Many proteins have been investigated in model organisms such as many bacteria, baker's yeast, fruit flies, zebra fish or mice, for which experiments can be often done more easily than with human cells. To predict the function, structure, or other properties of a protein for which only its sequence of amino acids is known, the protein sequence is compared to the sequences of other proteins in public databases. If a protein with sufficiently similar sequence is found, the two proteins are likely to be evolutionarily related ("homologous"). In that case, they are likely to share similar structures and functions. Therefore, if a protein with a sufficiently similar sequence and with known functions and/or structure can be found by the sequence search, the unknown prot
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https://en.wikipedia.org/wiki/Universal%20quadratic%20form
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In mathematics, a universal quadratic form is a quadratic form over a ring that represents every element of the ring. A non-singular form over a field which represents zero non-trivially is universal.
Examples
Over the real numbers, the form x2 in one variable is not universal, as it cannot represent negative numbers: the two-variable form over R is universal.
Lagrange's four-square theorem states that every positive integer is the sum of four squares. Hence the form over Z is universal.
Over a finite field, any non-singular quadratic form of dimension 2 or more is universal.
Forms over the rational numbers
The Hasse–Minkowski theorem implies that a form is universal over Q if and only if it is universal over Qp for all p (where we include , letting Q∞ denote R). A form over R is universal if and only if it is not definite; a form over Qp is universal if it has dimension at least 4. One can conclude that all indefinite forms of dimension at least 4 over Q are universal.
See also
The 15 and 290 theorems give conditions for a quadratic form to represent all positive integers.
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https://en.wikipedia.org/wiki/Weyl%20distance%20function
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In combinatorial geometry, the Weyl distance function is a function that behaves in some ways like the distance function of a metric space, but instead of taking values in the positive real numbers, it takes values in a group of reflections, called the Weyl group (named for Hermann Weyl). This distance function is defined on the collection of chambers in a mathematical structure known as a building, and its value on a pair of chambers a minimal sequence of reflections (in the Weyl group) to go from one chamber to the other. An adjacent sequence of chambers in a building is known as a gallery, so the Weyl distance function is a way of encoding the information of a minimal gallery between two chambers. In particular, the number of reflections to go from one chamber to another coincides with the length of the minimal gallery between the two chambers, and so gives a natural metric (the gallery metric) on the building. According to , the Weyl distance function is something like a geometric vector: it encodes both the magnitude (distance) between two chambers of a building, as well as the direction between them.
Definitions
We record here definitions from . Let be the Coxeter complex associated to a group W generated by a set of reflections S. The vertices of are the elements of W, and the chambers of the complex are the cosets of S in W. The vertices of each chamber can be colored in a one-to-one manner by the elements of S so that no adjacent vertices of the complex receive the same color. This coloring, although essentially canonical, is not quite unique. The coloring of a given chamber is not uniquely determined by its realization as a coset of S. But once the coloring of a single chamber has been fixed, the rest of the Coxeter complex is uniquely colorable. Fix such a coloring of the complex.
A gallery is a sequence of adjacent chambers
Because these chambers are adjacent, any consecutive pair of chambers share all but one vertex. Denote the color o
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https://en.wikipedia.org/wiki/Reconstruction%20conjecture
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Informally, the reconstruction conjecture in graph theory says that graphs are determined uniquely by their subgraphs. It is due to Kelly and Ulam.
Formal statements
Given a graph , a vertex-deleted subgraph of is a subgraph formed by deleting exactly one vertex from . By definition, it is an induced subgraph of .
For a graph , the deck of G, denoted , is the multiset of isomorphism classes of all vertex-deleted subgraphs of . Each graph in is called a card. Two graphs that have the same deck are said to be hypomorphic.
With these definitions, the conjecture can be stated as:
Reconstruction Conjecture: Any two hypomorphic graphs on at least three vertices are isomorphic.
(The requirement that the graphs have at least three vertices is necessary because both graphs on two vertices have the same decks.)
Harary suggested a stronger version of the conjecture:
Set Reconstruction Conjecture: Any two graphs on at least four vertices with the same sets of vertex-deleted subgraphs are isomorphic.
Given a graph , an edge-deleted subgraph of is a subgraph formed by deleting exactly one edge from .
For a graph , the edge-deck of G, denoted , is the multiset of all isomorphism classes of edge-deleted subgraphs of . Each graph in is called an edge-card.
Edge Reconstruction Conjecture: (Harary, 1964) Any two graphs with at least four edges and having the same edge-decks are isomorphic.
Recognizable properties
In context of the reconstruction conjecture, a graph property is called recognizable if one can determine the property from the deck of a graph. The following properties of graphs are recognizable:
Order of the graph – The order of a graph , is recognizable from as the multiset contains each subgraph of created by deleting one vertex of . Hence
Number of edges of the graph – The number of edges in a graph with vertices, is recognizable. First note that each edge of occurs in members of . This is true by the definition of which ensure
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https://en.wikipedia.org/wiki/WAVE%20regulatory%20complex
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The WAVE regulatory complex (WRC, SCAR complex) is a five-subunit protein complex in the Wiskott-Aldrich syndrome protein (WASP) family involved in the formation of the actin cytoskeleton through interaction with the Arp2/3 complex. The holocomplex comprises WAVE1 (also known as WASF1), CYFIP1, ABI2, Nap1 and HSPC300 in its canonical form, or orthologues of these.
Composition
The proteins within the WRC form a CYFIP1-Nap1 heterodimer and a WAVE1-Abi2-HSPC300 heterotrimer, and following interaction with Rac1, the holocomplex has been observed in a CYFIP1-Nap1-Abi2 heterotrimer subcomplex and an active WAVE1-HSPC300 heterodimer subcomplex.
Function
WRC recruitment to the sites of actin nucleation events at the cell periphery is mediated by the binding of a number of ligands containing a conserved WRC interacting receptor sequence (WIRS) which binds to a conserved location shared across the surfaces of Abi2 and CYFIP1. The WRC is activated by interaction with the Rac1 (via the CYFIP1 component of the complex) and Arf small GTPases (such as ARF1, ARF5, and ARF6 ) or the similar protein ARL1, which causes dissociation of the CYFIP1-Nap1-Abi2 heterotrimer at the membrane periphery. This allows the V domain of the WAVE1 component to interact with the actin monomers while its CA domain interacts with the Arp2/3 complex, allowing the Arp2/3 complex to act as a nucleation core for the branching and extension of actin filaments.
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https://en.wikipedia.org/wiki/0.999...
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In mathematics, 0.999... (also written as 0., 0. or 0.(9)) is a notation for the repeating decimal consisting of an unending sequence of 9s after the decimal point. This repeating decimal is a numeral that represents the smallest number no less than every number in the sequence (0.9, 0.99, 0.999, ...); that is, the supremum of this sequence. This number is equal to1. In other words, "0.999..." is not "almost exactly" or "very, very nearly but not quite" rather, "0.999..." and "1" represent the same number.
There are many ways of showing this equality, from intuitive arguments to mathematically rigorous proofs. The technique used depends on the target audience, background assumptions, historical context, and preferred development of the real numbers, the system within which 0.999... is commonly defined. In other systems, 0.999... can have the same meaning, a different definition, or be undefined.
More generally, every nonzero terminating decimal has two equal representations (for example, 8.32 and 8.31999...), which is a property of all positional numeral system representations regardless of base. The utilitarian preference for the terminating decimal representation contributes to the misconception that it is the only representation. For this and other reasons—such as rigorous proofs relying on non-elementary techniques, properties, or disciplines—some people can find the equality sufficiently counterintuitive that they question or reject it. This has been the subject of several studies in mathematics education.
Elementary proof
There is an elementary proof of the equation , which uses just the mathematical tools of comparison and addition of (finite) decimal numbers, without any reference to more advanced topics such as series, limits, formal construction of real numbers, etc. The proof, given below, is a direct formalization of the intuitive fact that, if one draws 0.9, 0.99, 0.999, etc. on the number line there is no room left for placing a number between
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https://en.wikipedia.org/wiki/Circuit%20extraction
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The electric circuit extraction or simply circuit extraction, also netlist extraction, is the translation of an integrated circuit layout back into the electrical circuit (netlist) it is intended to represent. This extracted circuit is needed for various purposes including circuit simulation, static timing analysis, signal integrity, power analysis and optimization, and logic to layout comparison. Each of these functions require a slightly different representation of the circuit, resulting in the need for multiple layout extractions. In addition, there may be a postprocessing step of converting the device-level circuit into a purely digital circuit, but this is not considered part of the extraction process.
The detailed functionality of an extraction process will depend on its system environment. The simplest form of extracted circuit may be in the form of a netlist, which is formatted for a particular simulator or analysis program. A more complex extraction may involve writing the extracted circuit back into the original database containing the physical layout and the logic diagram. In this case, by associating the extracted circuit with the layout and the logic network, the user can cross-reference any point in the circuit to its equivalent points in the logic and layout (cross-probing). For simulation or analysis, various formats of netlist can then be generated using programs that read the database and generate the appropriate text information.
In extraction, it is often helpful to make an (informal) distinction between designed devices, which are devices that are deliberately created by the designer, and parasitic devices, which were not explicitly intended by the designer but are inherent in the layout of the circuit.
Primarily there are three different parts to the extraction process. These are designed device extraction, interconnect extraction, and parasitic device extraction. These parts are inter-related since various device extractions can change th
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https://en.wikipedia.org/wiki/GM2A
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GM2 ganglioside activator also known as GM2A is a protein which in humans is encoded by the GM2A gene.
Function
The protein encoded by this gene is a small glycolipid transport protein which acts as a substrate specific co-factor for the lysosomal enzyme β-hexosaminidase A. β-hexosaminidase A, together with GM2 ganglioside activator, catalyzes the degradation of the ganglioside GM2, and other molecules containing terminal N-acetyl hexosamines.
GM2A is a lipid transfer protein that stimulates the enzymatic processing of gangliosides, and also T-cell activation through lipid presentation. This protein binds molecules of ganglioside GM2, extracts them from membranes, and presents them to beta-hexosaminidase A for cleavage of N-acetyl-D-galactosamine and conversion to GM3.
It was identified as a member of ML domain family of proteins involved in innate immunity and lipid metabolism in the SMART database.
.
Regulation
In melanocytic cells GM2A gene expression may be regulated by MITF.
Clinical significance
Mutations in this gene, inherited in an autosomal recessive pattern, result in GM2-gangliosidosis, AB variant, a rare GM2 gangliosidosis that has symptoms and pathology identical with Tay–Sachs disease and Sandhoff disease.
GM2A mutations are rarely reported, and the cases that are observed often occur with consanguineous parents or in genetically isolated populations.
Because AB variant is so rarely diagnosed, even in infants, it is likely that most mutations of GM2A are fatal in the fetus in homozygotes and genetic compounds, and thus are never observed clinically.
See also
Gangliosidosis
Sandhoff disease
Tay–Sachs disease
Hexosaminidase
GM1
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