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https://en.wikipedia.org/wiki/Replica%20cluster%20move
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Replica cluster move in condensed matter physics refers to a family of non-local cluster algorithms used to simulate spin glasses. It is an extension of the Swendsen-Wang algorithm in that it generates non-trivial spin clusters informed by the interaction states on two (or more) replicas instead of just one. It is different from the replica exchange method (or parallel tempering), as it performs a non-local update on a fraction of the sites between the two replicas at the same temperature, while parallel tempering directly exchanges all the spins between two replicas at different temperature. However, the two are often used alongside to achieve state-of-the-art efficiency in simulating spin-glass models.
The Chayes-Matcha-Redner representation
The Chayes-Matcha-Redner (CMR) representation is a graphical representation of the Ising spin glass which extends the standard FK representation. It is based on the observation that the total Hamiltonian of two independent Ising replicas α and β,
can be written as the Hamiltonian of a 4-state clock model. To see this, we define the following mapping
where is the orientation of the 4-state clock, then the total Hamiltonian can be represented as
In the graphical representation of this model, there are two types of bonds that can be open, referred to as blue and red. To generate the bonds on the lattice, the following rules are imposed:
If , or when the interactions on edge are satisfied on both replicas, then a blue bond is open with probability .
If , or when the interaction on edge is satisfied in exactly one replica, then a red bond is open with probability .
Otherwise, a closed bond is formed.
Under these rules, it can be checked that a cycle of open bonds can only contain an even number of red bonds. A cluster formed with blue bonds is referred to as a blue cluster, and a super-cluster formed together with both blue and red bonds is referred to as a grey cluster.
Once the clusters are generated, there are two
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https://en.wikipedia.org/wiki/D37D
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The D37D Minuteman III flight computer was initially supplied with the LGM-30G missile, as part of the NS-20 navigation system. The NS-20 D37D flight computer is a miniaturized general purpose (serial transmission) digital computer. The new NS-50 missile guidance computer (MGC) is built around a 16-bit high-speed microprocessor chip set. They are both designed to solve real-time positional error problems under the adverse conditions encountered in airborne weapon systems. They accept and process data and generate steering signals with sufficient accuracy and speed to meet the requirements of the inertial guidance and flight control systems of the Minuteman ICBMs.
Computer operation is controlled by an internally stored program which is loaded from a magnetic tape cartridge at the launch facility (LF). Both the D37D computer and the MGC are designed and programmed to control the Minuteman III missile throughout the powered portion of flight. After thrust termination they also control the PBV for the reentry vehicle (RV) deployment phase. In addition, they control the alignment of the inertial platform and test/monitor the guidance & control (G&C) system and other components to determine continued readiness while missiles are in alert status. The D37D computer began to be replaced by the MGC in 2000 as part of the Guidance Replacement Program (GRP), with fielding planned through 2008. The MGC incorporates the amplifier assembly functions.
When a launch is commanded, a complete retesting of the G&C system is made prior to entering the flight program. During flight, the computer uses missile attitude, change of attitude rate, and velocity signal inputs to solve a series of guidance, steering, and control equations. It also generates missile steering commands and controls staging and thrust termination. Finally, the computer determines whether or not to provide pre-arm signals to the warhead. The pre-arm decision is based on flight safety checks made during powered fli
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https://en.wikipedia.org/wiki/Yau%27s%20conjecture
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In differential geometry, Yau's conjecture from 1982, is a mathematical conjecture which states that a closed Riemannian 3-manifold has an infinite number of smooth closed immersed minimal surfaces. It is named after Shing-Tung Yau. It was the first problem in the minimal submanifolds section in Yau's list of open problems.
The conjecture has recently been claimed by Kei Irie, Fernando Codá Marques and André Neves in the generic case, and by Antoine Song in full generality.
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https://en.wikipedia.org/wiki/UNIVAC%201102
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The UNIVAC 1102 or ERA 1102 was designed by Engineering Research Associates for the United States Air Force's Arnold Engineering Development Center in Tullahoma, Tennessee in response to a request for proposal issued in 1950. The Air Force needed three computers to do data reduction for two wind tunnels and an engine test facility.
The 1102 was a variant of the UNIVAC 1101, using its 24-bit word and a smaller (only 8,192 words) drum memory. The machine had 2,700 vacuum tubes, weighed , and occupied of floor area.
The computers were connected to data channels coming from the wind tunnels and the engine facility. There were five typewriters for printed output, five paper tape punches, and four pen plotters to produce graphs.
The three computers and related peripherals were delivered between July 1954 and July 1956 at a total price of $1,400,000. Software for the computers was developed entirely at the Arnold Engineering Development center. All programming was done in machine code (assemblers and compilers were never developed).
See also
List of UNIVAC products
History of computing hardware
List of vacuum tube computers
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https://en.wikipedia.org/wiki/Sodium%20sulfite
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Sodium sulfite (sodium sulphite) is the inorganic compound with the chemical formula Na2SO3. A white, water-soluble solid, it is used commercially as an antioxidant and preservative. It is also suitable for the softening of lignin in the pulping and refining processes of wood and lignocellulosic materials. A heptahydrate is also known but it is less useful because of its greater susceptibility toward oxidation by air.
Preparation
Sodium sulfite can be prepared by treating a solution of sodium hydroxide with sulfur dioxide. When conducted in warm water, Na2SO3 initially precipitates as a white solid. With more SO2, the solid dissolves to give the disulfite, which crystallizes upon cooling.
SO2 + 2 NaOH -> Na2SO3 + H2O
Sodium sulfite is made industrially by treating sulfur dioxide with a solution of sodium carbonate. The overall reaction is:
SO2 + Na2CO3 -> Na2SO3 + CO2
Uses
Sodium sulfite is primarily used in the pulp and paper industry. It has been also applied in the thermomechanical conversion of wood to fibres (defibration) for producing medium density fibreboards (MDF).
As an oxygen scavenger agent, it is used to treat water being fed to steam boilers to avoid corrosion problems, in the photographic industry, it protects developer solutions from oxidation and (as hypo clear solution) to wash fixer (sodium thiosulfate) from film and photo-paper emulsions.
As a reducing agent it is used in the textile industry as a bleaching, desulfurizing, and dechlorinating agent (e.g. in swimming pools). Its reducing properties are exploited in its use as a preservative to prevent dried fruit from discoloring, and for preserving meats.
It is used as a reagent in sulfonation and sulfomethylation agent. It is used in the production of sodium thiosulfate.
The Wellman–Lord process utilizes sodium sulfite for flue gas desulfurization.
Reactions
Sodium sulfite is primarily used as a mild reducing agent. The heptahydrate crystals effloresce in warm dry air.
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https://en.wikipedia.org/wiki/List%20of%20the%20verified%20shortest%20people
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This list includes the shortest ever verified people in their lifetime or profession. The entries below are broken down into different categories which range from sex, to age group and occupations. Most of the sourcing is done by Guinness World Records which in the last decade has added new categories for "mobile" and "non-mobile" men and women. The world's shortest verified man is Chandra Bahadur Dangi, while for women Pauline Musters holds the record.
Men
Women
Shortest pairs
Shortest by age group
This was Nisa's baby height, she later grew.
This was Francis Joseph Flynn's shortest height, because he grew in height after age 16; he is not listed as one of the world's shortest men.
Filed under "Shortest woman to give birth".
Shortest by occupation
Actors
Artists and writers
Athletes
Politicians
Others
See also
Dwarfism
Pygmy peoples
Caroline Crachami, a person about tall
Little people (mythology)
List of dwarfism organisations
Dwarfs and pygmies in ancient Egypt
List of tallest people
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https://en.wikipedia.org/wiki/Information%20and%20Software%20Technology
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Information and Software Technology is a peer-reviewed scientific journal on software development and related issues, published by Elsevier. The journal was established in 1959 as Data Processing, obtaining its current title in 1987. The journal is abstracted and indexed in Scopus.
According to the Journal Citation Reports, the journal has a 2021 impact factor of 3.862.
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https://en.wikipedia.org/wiki/Advection%20upstream%20splitting%20method
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The Advection Upstream Splitting Method (AUSM) is a numerical method used to solve the advection equation in computational fluid dynamics. It is particularly useful for simulating compressible flows with shocks and discontinuities.
The AUSM is developed as a numerical inviscid flux function for solving a general system of conservation equations. It is based on the upwind concept and was motivated to provide an alternative approach to other upwind methods, such as the Godunov method, flux difference splitting methods by Roe, and Solomon and Osher, flux vector splitting methods by Van Leer, and Steger and Warming.
The AUSM first recognizes that the inviscid flux consist of two physically distinct parts, i.e., convective and pressure fluxes. The former is associated with the flow (advection) speed, while the latter with the acoustic speed; or respectively classified as the linear and nonlinear fields. Currently, the convective and pressure fluxes are formulated using the eigenvalues of the flux Jacobian matrices. The method was originally proposed by Liou and Steffen for the typical compressible aerodynamic flows, and later substantially improved in to yield a more accurate and robust version. To extend its capabilities, it has been further developed in for all speed-regimes and multiphase flow. Its variants have also been proposed.
Features
The Advection Upstream Splitting Method has many features. The main features are:
accurate capturing of shock and contact discontinuities
entropy-satisfying solution
positivity-preserving solution
algorithmic simplicity (not requiring explicit eigen-structure of the flux Jacobian matrices) and straightforward extension to additional conservation laws
free of “carbuncle” phenomena
uniform accuracy and convergence rate for all Mach numbers.
Since the method does not specifically require eigenvectors, it is especially attractive for the system whose eigen-structure is not known explicitly, as the case of two-fluid equations for
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https://en.wikipedia.org/wiki/Decision%20table
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Decision tables are a concise visual representation for specifying which actions to perform depending on given conditions. They are algorithms whose output is a set of actions. The information expressed in decision tables could also be represented as decision trees or in a programming language as a series of if-then-else and switch-case statements.
Overview
Each decision corresponds to a variable, relation or predicate whose possible values are listed among the condition alternatives. Each action is a procedure or operation to perform, and the entries specify whether (or in what order) the action is to be performed for the set of condition alternatives the entry corresponds to.
To make them more concise, many decision tables include in their condition alternatives a don't care symbol. This can be a hyphen or blank, although using a blank is discouraged as it may merely indicate that the decision table has not been finished. One of the uses of decision tables is to reveal conditions under which certain input factors are irrelevant on the actions to be taken, allowing these input tests to be skipped and thereby streamlining decision-making procedures.
Aside from the basic four quadrant structure, decision tables vary widely in the way the condition alternatives and action entries are represented. Some decision tables use simple true/false values to represent the alternatives to a condition (similar to if-then-else), other tables may use numbered alternatives (similar to switch-case), and some tables even use fuzzy logic or probabilistic representations for condition alternatives. In a similar way, action entries can simply represent whether an action is to be performed (check the actions to perform), or in more advanced decision tables, the sequencing of actions to perform (number the actions to perform).
A decision table is considered balanced or complete if it includes every possible combination of input variables. In other words, balanced decision tables pres
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https://en.wikipedia.org/wiki/Elias%20Bassalygo%20bound
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The Elias Bassalygo bound is a mathematical limit used in coding theory for error correction during data transmission or communications.
Definition
Let be a -ary code of length , i.e. a subset of . Let be the rate of , the relative distance and
be the Hamming ball of radius centered at . Let be the volume of the Hamming ball of radius . It is obvious that the volume of a Hamming Ball is translation-invariant, i.e. indifferent to In particular,
With large enough , the rate and the relative distance satisfy the Elias-Bassalygo bound:
where
is the q-ary entropy function and
is a function related with Johnson bound.
Proof
To prove the Elias–Bassalygo bound, start with the following Lemma:
Lemma. For and , there exists a Hamming ball of radius with at least
codewords in it.
Proof of Lemma. Randomly pick a received word and let be the Hamming ball centered at with radius . Since is (uniform) randomly selected the expected size of overlapped region is
Since this is the expected value of the size, there must exist at least one such that
otherwise the expectation must be smaller than this value.
Now we prove the Elias–Bassalygo bound. Define By Lemma, there exists a Hamming ball with codewords such that:
By the Johnson bound, we have . Thus,
The second inequality follows from lower bound on the volume of a Hamming ball:
Putting in and gives the second inequality.
Therefore we have
See also
Singleton bound
Hamming bound
Plotkin bound
Gilbert–Varshamov bound
Johnson bound
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https://en.wikipedia.org/wiki/LG%20Display
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LG Display (Korean: LG 디스플레이) is one of the world's largest manufacturers and supplier of thin-film transistor liquid crystal display (TFT-LCD) panels, OLEDs and flexible displays. LG Display is headquartered in Seoul, South Korea, and currently operates nine fabrication facilities and seven back-end assembly facilities in Korea, China, Poland and Mexico.
LG Display has manufactured displays used in products such as the iPhone 14 Pro and Sony's OLED TVs.
History
LG Display was originally formed as a joint venture by the Korean electronics company LG Electronics and the Dutch company Philips in 1999 to manufacture active matrix liquid crystal displays (LCDs) and was formerly known as LG.Philips LCD, but Philips sold off all its shares in late 2008. Both companies also had another joint venture, called LG.Philips Displays, dedicated to manufacturing cathode ray tubes, deflection yokes, and related materials such as glass and phosphors.
On 12 December 2008, LG.Philips LCD announced its plan to change its corporate name to LG Display upon receiving approval at the company's annual general meeting of shareholders on 29 February. The company claimed the name change reflected changes following the reduction of Philips' equity stake.
The company has eight manufacturing plants in Gumi and Paju, South Korea. It also has a module assembly plant in Nanjing and Guangzhou in China and Wroclaw in Poland.
LG Display became an independent company in July 2004 when it was concurrently listed on the New York Stock Exchange () and the South Korean Stock Exchange ().
They are one of the main licensed manufacturers of the more color-accurate IPS panels used by Dell, NEC, ASUS, Apple (including iMacs, iPads, iPhones, iPod Touches) and others, which were developed by Hitachi.
LCD price fixing
In December 2010, the EU fined LG Display €215 million for its part in an LCD price fixing scheme. Other companies were fined for a combined total of €648.9 million, including Chimei Innolux,
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https://en.wikipedia.org/wiki/Petr%20H%C3%A1jek
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Petr Hájek (; 6 February 1940 – 26 December 2016) was a Czech scientist in the area of mathematical logic and a professor of mathematics. Born in Prague, he worked at the Institute of Computer Science at the Academy of Sciences of the Czech Republic and as a lecturer at the faculty of mathematics and physics at the Charles University in Prague and at the Faculty of Nuclear Sciences and Physical Engineering of the Czech Technical University in Prague.
Academics
Petr Hájek studied at the faculty of mathematics and physics of the Charles University in Prague. Influenced by Petr Vopěnka, he specialized in set theory and arithmetic, and later also in logic and artificial intelligence. He contributed to establishing the mathematical fundamentals of fuzzy logic. Following the Velvet Revolution, he was appointed a senior lecturer (1993) and a professor (1997). From 1992 to 2000 he held the position of chairman of the Institute of Computer Science at the Academy of Sciences of the Czech Republic. From 1996 to 2003 he was also president of the Kurt Gödel Society.
Later, he graduated from the Academy of Performing Arts in Prague, where he studied the pipe organ under Jiří Reinberger to become an organ player in a church.
Awards
2002, Medal of the Minister of Education of the Czech Republic
2006, Medal of Merit, third grade, in the area of sciences by President of the Czech Republic Václav Klaus
2008, doctor honoris causa from Silesian University in Opava
Papers
See also
Semiset
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https://en.wikipedia.org/wiki/Total%20functional%20programming
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Total functional programming (also known as strong functional programming, to be contrasted with ordinary, or weak functional programming) is a programming paradigm that restricts the range of programs to those that are provably terminating.
Restrictions
Termination is guaranteed by the following restrictions:
A restricted form of recursion, which operates only upon 'reduced' forms of its arguments, such as Walther recursion, substructural recursion, or "strongly normalizing" as proven by abstract interpretation of code.
Every function must be a total (as opposed to partial) function. That is, it must have a definition for everything inside its domain.
There are several possible ways to extend commonly used partial functions such as division to be total: choosing an arbitrary result for inputs on which the function is normally undefined (such as for division); adding another argument to specify the result for those inputs; or excluding them by use of type system features such as refinement types.
These restrictions mean that total functional programming is not Turing-complete. However, the set of algorithms that can be used is still huge. For example, any algorithm for which an asymptotic upper bound can be calculated (by a program that itself only uses Walther recursion) can be trivially transformed into a provably-terminating function by using the upper bound as an extra argument decremented on each iteration or recursion.
For example, quicksort is not trivially shown to be substructural recursive, but it only recurs to a maximum depth of the length of the vector (worst-case time complexity O(n2)). A quicksort implementation on lists (which would be rejected by a substructural recursive checker) is, using Haskell:
import Data.List (partition)
qsort [] = []
qsort [a] = [a]
qsort (a:as) = let (lesser, greater) = partition (<a) as
in qsort lesser ++ [a] ++ qsort greater
To make it substructural recursive using the length of th
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https://en.wikipedia.org/wiki/Geographic%20tongue
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Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.
Signs and symptoms
In health, the dorsal surface of the tongue is covered in tuft-like projections called lingual papillae (some of which are associated with taste buds), which give the tongue an irregular surface texture and a white-pink color. Geographic tongue is characterized by areas of atrophy and depapillation (loss of papillae), leaving an erythematous (darker red) and smoother surface than the unaffected areas. The depapillated areas are usually well-demarcated, and bordered by a slightly raised, white, yellow or grey, serpiginous (snaking) peripheral zone. A lesion of geographic tongue may start as a white patch before the depapillation occurs. In certain cases there may be only one lesion, but this is uncommon; the lesions will typically occur in multiple locations on the tongue and coalesce over time to form the typical map-like appearance. The lesions usually change in shape and size, and migrate to other areas, sometimes within hours. The condition may affect only part of the tongue, with a predilection for the tip and the sides of the tongue, or the entire dorsal surface at any one time. The condition goes through periods of remission and relapse. Loss of the white peripheral zone is thought to signify per
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https://en.wikipedia.org/wiki/Adil%20Shamoo
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Adil E. Shamoo (born August 1, 1941) is an Iraqi biochemist with an interest in biomedical ethics and foreign policy. He is currently a professor at the Department of Biochemistry and Molecular Biology at the University of Maryland.
Professional
In 1998, he founded the journal Accountability in Research, and has served as its editor-in-chief since its inception. He is on the editorial boards of several other journals, including the Drug Information Journal. From 2000 to 2002, he served on the advisory committee for National Human Research Protections. Although he has an extensive list of publications in the fields of biochemistry and microbiology, he is currently busied by his work as an analyst for Foreign Policy In Focus, a project of the Institute for Policy Studies, a think tank, to which he has been contributing since 2005. Shamoo has also authored and co-authored many op-eds on U.S. foreign policy that have been published in newspapers across the country.
Shamoo is also currently occupied with his work in the field of ethics. Since 1991, he has taught a graduate course at the University of Maryland entitled "Responsible Conduct of Research". In 1995, he co-founded the human rights organization, Citizens for Responsible Care and Research (CIRCARE). In 2003, he chaired a Special Issue GlaxoSmithKline Pharmaceuticals' Ethics Advisory Group. Shamoo was then appointed to the Armed Forces Epidemiological Board (AFEB) of the United States Department of Defense as ethics consultant (2003–2004). Because he served as chairman on nine international conferences in ethics in research and human research protection, he was asked to testify before a congressional committee and the National Bioethics Advisory Commission. Since 2006, he has served on the Defense Health Board. And from 2006 to 2007,Shamoo was a member of the new Maryland Governor's Higher Education Transition Working Group. He was an invited participant and presenter in the 2007 New Year Renaissance Weekend.
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https://en.wikipedia.org/wiki/Mr.%20Do%27s%20Castle
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Mr. Do's Castle is a platform game released in arcades by Universal in September 1983. In Japan, the game is titled Mr. Do! versus Unicorns. Marketed as a sequel to the original Mr. Do! released one year earlier, the game bears a far closer resemblance to Universal's Space Panic from 1980. It began as a game called Knights vs. Unicorns, but the U.S. division of Universal persuaded the Japanese arm to modify the graphics into a Mr. Do! game following the first game's popularity.
Gameplay
The object of Mr. Do's Castle is to score as many points as possible by collecting cherries and/or defeating unicorn-like monsters. The game takes place in a castle filled with platforms and ladders —reminiscent of Space Panic (1980)—some of which can be flipped from one platform to another, much like a kickstand on a bicycle. The player controls Mr. Do as he collects cherries by using a hammer to knock out blocks that contain them from the various platforms. Empty holes left by the knocked-out blocks serve as traps for the monsters —if a monster falls into a hole, the player can then defeat it by causing a block above the monster to fall on top of it (and additional points are scored if such a monster falls multiple levels en route to its destruction). If the player takes too long to complete a level, the monsters transform into faster, more difficult forms —at first green in color, later blue —that rapidly multiply once they turn blue. The game advances to the next level when all cherries on the level have been collected or all enemies have been defeated. The player loses a life if Mr. Do is caught by a monster, and the game ends when the player runs out of lives.
As in Mr. Do!, the player can earn an extra life by collecting all of the letters from the word "EXTRA". Regular monsters can be changed into monsters bearing the EXTRA letters by collecting all three keys distributed around the playfield and then picking up a magic shield from the top floor. Monsters in this s
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https://en.wikipedia.org/wiki/Inner%20mitochondrial%20membrane
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The inner mitochondrial membrane (IMM) is the mitochondrial membrane which separates the mitochondrial matrix from the intermembrane space.
Structure
The structure of the inner mitochondrial membrane is extensively folded and compartmentalized. The numerous invaginations of the membrane are called cristae, separated by crista junctions from the inner boundary membrane juxtaposed to the outer membrane. Cristae significantly increase the total membrane surface area compared to a smooth inner membrane and thereby the available working space for oxidative phosphorylation.
The inner membrane creates two compartments. The region between the inner and outer membrane, called the intermembrane space, is largely continuous with the cytosol, while the more sequestered space inside the inner membrane is called the matrix.
Cristae
For typical liver mitochondria, the area of the inner membrane is about 5 times as large as the outer membrane due to cristae. This ratio is variable and mitochondria from cells that have a greater demand for ATP, such as muscle cells, contain even more cristae. Cristae membranes are studded on the matrix side with small round protein complexes known as F1 particles, the site of proton-gradient driven ATP synthesis. Cristae affect overall chemiosmotic function of mitochondria.
Cristae junctions
Cristae and the inner boundary membranes are separated by junctions. The end of cristae are partially closed by transmembrane protein complexes that bind head to head and link opposing crista membranes in a bottleneck-like fashion. For example, deletion of the junction protein IMMT leads to a reduced inner membrane potential and impaired growth and to dramatically aberrant inner membrane structures which form concentric stacks instead of the typical invaginations.
Composition
The inner membrane of mitochondria is similar in lipid composition to the membrane of bacteria. This phenomenon can be explained by the endosymbiont hypothesis of the origin of mito
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https://en.wikipedia.org/wiki/ASCI%20Blue%20Pacific
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ASCI Blue Pacific was a supercomputer installed at the Lawrence Livermore National Laboratory (LLNL) in Livermore, CA at the end of 1998. It was a collaboration between IBM and LLNL.
It was an IBM RS/6000 SP massively parallel processing system. It contained 5,856 PowerPC 604e microprocessors. Its theoretical top performance was 3.9 teraflops.
It was built as a stage of the Accelerated Strategic Computing Initiative (ASCI) started by the U.S. Department of Energy and the National Nuclear Security Administration to build a simulator to replace live nuclear weapon testing following the moratorium on testing started by President George H. W. Bush in 1992 and extended by Bill Clinton in 1993.
External links
One-of-a-kind computers
Lawrence Livermore National Laboratory
IBM supercomputers
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https://en.wikipedia.org/wiki/COSMO-RS
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COSMO-RS (short for COnductor like Screening MOdel for Real Solvents) is a quantum chemistry based equilibrium thermodynamics method with the purpose of predicting chemical potentials µ in liquids.
It processes the screening charge density σ on the surface of molecules to calculate the chemical potential µ of each species in solution. Perhaps in dilute solution a constant potential must be considered. As an initial step a quantum chemical COSMO calculation for all molecules is performed and the results (e.g. the screening charge density) are stored in a database. In a separate step COSMO-RS uses the stored COSMO results to calculate the chemical potential of the molecules in a liquid solvent or mixture. The resulting chemical potentials are the basis for other thermodynamic equilibrium properties such as activity coefficients, solubility, partition coefficients, vapor pressure and free energy of solvation. The method was developed to provide a general prediction method with no need for system specific adjustment.
Due to the use of σ from COSMO calculations, COSMO-RS does not require functional group parameters. Quantum chemical effects like group-group interactions, mesomeric effects and inductive effects also are incorporated into COSMO-RS by this approach.
The COSMO-RS method was first published in 1995 by A. Klamt. A refined version of COSMO-RS was published in 1998 and is the basis for newer developments and reimplementations.
Basic principles
The below description is a simplified overview of the COSMO-RS version published in 1998.
Assumptions
The liquid state is incompressible
All parts of the molecular surfaces can be in contact with each other
Only pairwise interactions of molecular surface patches are allowed
As long as the above assumptions hold, the chemical potential µ in solution can be calculated from the interaction energies of pairwise surface contacts.
COSMO-RS equations
Within the basic formulation of COSMO-RS, interaction terms depend o
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https://en.wikipedia.org/wiki/Microsoft%20CryptoAPI
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The Microsoft Windows platform specific Cryptographic Application Programming Interface (also known variously as CryptoAPI, Microsoft Cryptography API, MS-CAPI or simply CAPI) is an application programming interface included with Microsoft Windows operating systems that provides services to enable developers to secure Windows-based applications using cryptography. It is a set of dynamically linked libraries that provides an abstraction layer which isolates programmers from the code used to encrypt the data. The Crypto API was first introduced in Windows NT 4.0 and enhanced in subsequent versions.
CryptoAPI supports both public-key and symmetric key cryptography, though persistent symmetric keys are not supported. It includes functionality for encrypting and decrypting data and for authentication using digital certificates. It also includes a cryptographically secure pseudorandom number generator function CryptGenRandom.
CryptoAPI works with a number of CSPs (Cryptographic Service Providers) installed on the machine. CSPs are the modules that do the actual work of encoding and decoding data by performing the cryptographic functions. Vendors of HSMs may supply a CSP which works with their hardware.
Cryptography API: Next Generation
Windows Vista features an update to the Crypto API known as Cryptography API: Next Generation (CNG). It has better API factoring to allow the same functions to work using a wide range of cryptographic algorithms, and includes a number of newer algorithms that are part of the National Security Agency (NSA) Suite B. It is also flexible, featuring support for plugging custom cryptographic APIs into the CNG runtime. However, CNG Key Storage Providers still do not support symmetric keys. CNG works in both user and kernel mode, and also supports all of the algorithms from the CryptoAPI. The Microsoft provider that implements CNG is housed in Bcrypt.dll.
CNG also supports elliptic curve cryptography which, because it uses shorter keys for the
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https://en.wikipedia.org/wiki/RAM%20limit
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The maximum random access memory (RAM) installed in any computer system is limited by hardware, software and economic factors. The hardware may have a limited number of address bus bits, limited by the processor package or design of the system. Some of the address space may be shared between RAM, peripherals, and read-only memory. In the case of a microcontroller with no external RAM, the size of the RAM array is limited by the size of the integrated circuit die. In a packaged system, only enough RAM may be provided for the system's required functions, with no provision for addition of memory after manufacture.
Software limitations to usable physical RAM may be present. An operating system may only be designed to allocate a certain amount of memory, with upper address bits reserved to indicate designations such as I/O or supervisor mode or other security information. Or the operating system may rely on internal data structures with fixed limits for addressable memory.
For mass-market personal computers, there may be no financial advantage to a manufacturer in providing more memory sockets, address lines, or other hardware than necessary to run mass-market software. When memory devices were relatively expensive compared with the processor, often the RAM delivered with the system was much less than the address capacity of the hardware, because of cost.
Sometimes RAM limits can be overcome using special techniques. Bank switching allows blocks of RAM memory to be switched into the processor's address space when required, under program control. Operating systems routinely manage running programs using virtual memory, where individual program operate as if they have access to a large memory space that is being simulated by swapping memory areas with disk storage.
CPU addressing limits
For performance reasons, all the parallel address lines of an address bus must be valid at the same time, otherwise access to memory would be delayed and performance would be seriously
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https://en.wikipedia.org/wiki/Behaviour%20therapy
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Behaviour therapy or behavioural psychotherapy is a broad term referring to clinical psychotherapy that uses techniques derived from behaviourism and/or cognitive psychology. It looks at specific, learned behaviours and how the environment, or other people's mental states, influences those behaviours, and consists of techniques based on behaviorism's theory of learning: respondent or operant conditioning. Behaviourists who practice these techniques are either behaviour analysts or cognitive-behavioural therapists. They tend to look for treatment outcomes that are objectively measurable. Behaviour therapy does not involve one specific method, but it has a wide range of techniques that can be used to treat a person's psychological problems.
Behavioural psychotherapy is sometimes juxtaposed with cognitive psychotherapy. While cognitive behavioural therapy integrates aspects of both approaches, such as cognitive restructuring, positive reinforcement, habituation (or desensitisation), counterconditioning, and modelling.
Applied behaviour analysis (ABA) is the application of behaviour analysis that focuses on functionally assessing how behaviour is influenced by the observable learning environment and how to change such behaviour through contingency management or exposure therapies, which are used throughout clinical behaviour analysis therapies or other interventions based on the same learning principles.
Cognitive-behavioural therapy views cognition and emotions as preceding overt behaviour and implements treatment plans in psychotherapy to lessen the issue by managing competing thoughts and emotions, often in conjunction with behavioural learning principles.
A 2013 Cochrane review comparing behaviour therapies to psychological therapies found them to be equally effective, although at the time the evidence base that evaluates the benefits and harms of behaviour therapies was weak.
History
Precursors of certain fundamental aspects of behaviour therapy have been ide
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https://en.wikipedia.org/wiki/Okabayashi%20space
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The Okabayashi space (or medial division of the pararectal space) is an anatomical potential space in the pelvis.
The ureter divides the pararectal space into the Okabayashi space medially and the Latzko space laterally.
Borders
Dorsal - Levator ani
Superior - Uterine artery
Superior / Ventral- Posterior leaf of the broad ligament
Medial - Rectum
Lateral - Ureter
Contents
Inferior hypogastric plexus - The parasympathetic nerve supply to the bladder
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https://en.wikipedia.org/wiki/Ethenone
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In organic chemistry, ethenone is the formal name for ketene, an organic compound with formula or . It is the simplest member of the ketene class. It is an important reagent for acetylations.
Properties
Ethenone is a highly reactive gas (at standard conditions) and has a sharp irritating odour. It is only reasonably stable at low temperatures (−80 °C). It must therefore always be prepared for each use and processed immediately, otherwise a dimerization to diketene occurs or it reacts to polymers that are difficult to handle. The polymer content formed during the preparation is reduced, for example, by adding sulfur dioxide to the ketene gas. Because of its cumulative double bonds, ethenone is highly reactive and reacts in an addition reaction H-acidic compounds to the corresponding acetic acid derivatives. It does for example react with water to acetic acid or with primary or secondary amines to the corresponding acetamides.
Preparation
In industrial chemistry, ketene is produced by the dehydration reaction of acetic acid:
C2H4O2 -> C2H2O + H2O
On a laboratory scale it can be produced by the thermal decomposition of Meldrum's acid at temperatures greater than 200 °C.
History
When passed through heated pipes or electrically heated metal (like copper) wires at 500-600 °C in the presence of carbon disulfide, acetone decomposes into methane and ethenone, with 95% yield.
Ethenone was discovered at the same time by Hermann Staudinger (by reaction of bromoacetyl bromide with metallic zinc) The dehydration of acetic acid was reported in 1910.
The thermal decomposition of acetic anhydride was also described.
Natural occurrence
Ethenone has been observed to occur in space, in comets or in gas as part of the interstellar medium.
Use
Ethenone is used to make acetic anhydride from acetic acid. Generally it is used for the acetylation of chemical compounds.
Ethenone reacts with methanal in the presence of catalysts such as Lewis acids (AlCl3, ZnCl2 or BF3) to give
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https://en.wikipedia.org/wiki/Quadrel
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Quadrel is a puzzle video game developed by Loriciels and released in June 1991. It was released for MS-DOS, Amiga, Atari ST, and Amstrad CPC
Gameplay
The game consists of a series of screens composed of patterns created by criss-crossing lines. the object of the game is to color the image entirely by using the four or less colours available in each screen. The same color can not be used to fill in adjacent shapes, requiring the player to form a strategy in order to complete each screen. Each screen is treated as a separate game. Two modes of play are available. The basic mode is a timed challenge for a single player, the player is scored by the number of seconds they spend to complete each screen. The main mode is for two players or a single player against the computer. In this mode the number of times each color may be used is limited. The player who cannot take their turn due to the placement of colors on the screen or the lack appropriate colors available to use loses.
Reception
The game received poor to mixed reviews, varying from 37% to 76%.
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https://en.wikipedia.org/wiki/Metabotropic%20glutamate%20receptor
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The metabotropic glutamate receptors, or mGluRs, are a type of glutamate receptor that are active through an indirect metabotropic process. They are members of the group C family of G-protein-coupled receptors, or GPCRs. Like all glutamate receptors, mGluRs bind with glutamate, an amino acid that functions as an excitatory neurotransmitter.
Function and structure
The mGluRs perform a variety of functions in the central and peripheral nervous systems: For example, they are involved in learning, memory, anxiety, and the perception of pain. They are found in pre- and postsynaptic neurons in synapses of the hippocampus, cerebellum, and the cerebral cortex, as well as other parts of the brain and in peripheral tissues.
Like other metabotropic receptors, mGluRs have seven transmembrane domains that span the cell membrane. Unlike ionotropic receptors, metabotropic glutamate receptors are not ion channels. Instead, they activate biochemical cascades, leading to the modification of other proteins, such as ion channels. This can lead to changes in the synapse's excitability, for example by presynaptic inhibition of neurotransmission, or modulation and even induction of postsynaptic responses.
A dimeric organization of mGluRs is required for signaling induced by agonists.
Classification
Eight different types of mGluRs, labeled mGluR1 to mGluR8 ( to ), are divided into groups I, II, and III. Receptor types are grouped based on receptor structure and physiological activity. The mGluRs are further divided into subtypes, such as mGluR7a and mGluR7b.
Overview
Group I
The mGluRs in group I, including mGluR1 and mGluR5, are stimulated most strongly by the excitatory amino acid analog L-quisqualic acid. Stimulating the receptors causes the associated enzyme phospholipase C to hydrolyze phosphoinositide phospholipids in the cell's plasma membrane. This leads to the formation of inositol 1,4,5-trisphosphate (IP3) and diacyl glycerol. Due to its hydrophilic character, IP3 can
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https://en.wikipedia.org/wiki/List%20of%20unsolved%20problems%20in%20statistics
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There are many longstanding unsolved problems in mathematics for which a solution has still not yet been found. The notable unsolved problems in statistics are generally of a different flavor; according to John Tukey, "difficulties in identifying problems have delayed statistics far more than difficulties in solving problems." A list of "one or two open problems" (in fact 22 of them) was given by David Cox.
Inference and testing
How to detect and correct for systematic errors, especially in sciences where random errors are large (a situation Tukey termed uncomfortable science).
The Graybill–Deal estimator is often used to estimate the common mean of two normal populations with unknown and possibly unequal variances. Though this estimator is generally unbiased, its admissibility remains to be shown.
Meta-analysis: Though independent p-values can be combined using Fisher's method, techniques are still being developed to handle the case of dependent p-values.
Behrens–Fisher problem: Yuri Linnik showed in 1966 that there is no uniformly most powerful test for the difference of two means when the variances are unknown and possibly unequal. That is, there is no exact test (meaning that, if the means are in fact equal, one that rejects the null hypothesis with probability exactly α) that is also the most powerful for all values of the variances (which are thus nuisance parameters). Though there are many approximate solutions (such as Welch's t-test), the problem continues to attract attention as one of the classic problems in statistics.
Multiple comparisons: There are various ways to adjust p-values to compensate for the simultaneous or sequential testing of hypotheses. Of particular interest is how to simultaneously control the overall error rate, preserve statistical power, and incorporate the dependence between tests into the adjustment. These issues are especially relevant when the number of simultaneous tests can be very large, as is increasingly the case in
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https://en.wikipedia.org/wiki/Prime%20Suspects%3A%20The%20Anatomy%20of%20Integers%20and%20Permutations
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Prime Suspects: The Anatomy of Integers and Permutations is a graphic novel by Andrew Granville, Jennifer Granville, and Robert J. Lewis, released on August 6, 2019 and published by Princeton University Press.
Plot
Prime Suspects: Anatomy of Integers and Permutations is a unique graphic novel that blurs the boundaries between pure visual art, deep mathematics, film noir and police procedurals whilst exploring the nature of scientific research, the role of women in mathematics and paying homage to the titans of mathematical history.
Reception
Judith Reveal of the New York Journal of Books said that "Prime Suspects will appeal to... the mathematician who eats, sleeps, and drinks numbers, start on page one and just enjoy the story . . . the book is fun, and interesting, and a challenge on many levels."
Benjamin Linowitz of MAA Reviews stated that ". . . It's very difficult to write a book on an advanced topic in mathematics that's accessible to math students and enthusiasts yet touches on contemporary research that is of interest to a broad swath of practicing mathematicians. Prime Suspects is such a book. And it's entertaining to boot. I recommend it in the strongest terms."
Paolo Mancosu of the Journal Of Humanistic Mathematics said the book "does a terrific job at presenting readers with a fascinating and realistic picture of how mathematical research is conducted. It does so in a deep way and yet with a light hand without falling into the trap of transforming the novel into a lecture on advanced mathematics or on methodology. Both the story and the illustrations are a delight."
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https://en.wikipedia.org/wiki/Geometric%20programming
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A geometric program (GP) is an optimization problem of the form
where are posynomials and are monomials. In the context of geometric programming (unlike standard mathematics), a monomial is a function from to defined as
where and . A posynomial is any sum of monomials.
Geometric programming is
closely related to convex optimization: any GP can be made convex by means of a change of variables. GPs have numerous applications, including component sizing in IC design, aircraft design, maximum likelihood estimation for logistic regression in statistics, and parameter tuning of positive linear systems in control theory.
Convex form
Geometric programs are not in general convex optimization problems, but they can be transformed to convex problems by a change of variables and a transformation of the objective and constraint functions. In particular, after performing the change of variables and taking the log of the objective and constraint functions, the functions , i.e., the posynomials, are transformed into log-sum-exp functions, which are convex, and the functions , i.e., the monomials, become affine. Hence, this transformation transforms every GP into an equivalent convex program. In fact, this log-log transformation can be used to convert a larger class of problems, known as log-log convex programming (LLCP), into an equivalent convex form.
Software
Several software packages exist to assist with formulating and solving geometric programs.
MOSEK is a commercial solver capable of solving geometric programs as well as other non-linear optimization problems.
CVXOPT is an open-source solver for convex optimization problems.
GPkit is a Python package for cleanly defining and manipulating geometric programming models. There are a number of example GP models written with this package here.
GGPLAB is a MATLAB toolbox for specifying and solving geometric programs (GPs) and generalized geometric programs (GGPs).
CVXPY is a Python-embedded modeling language for s
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https://en.wikipedia.org/wiki/IBM%20Monochrome%20Display%20Adapter
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The Monochrome Display Adapter (MDA, also MDA card, Monochrome Display and Printer Adapter, MDPA) is IBM's standard video display card and computer display standard for the IBM PC introduced in 1981. The MDA does not have any pixel-addressable graphics modes, only a single monochrome text mode which can display 80 columns by 25 lines of high resolution text characters or symbols useful for drawing forms.
Hardware design
The original IBM MDA was an 8-bit ISA card with a Motorola 6845 display controller, 4 KB of RAM, a DE-9 output port intended for use with an IBM monochrome monitor, and a parallel port for attachment of a printer, avoiding the need to purchase a separate card.
Capabilities
The MDA was based on the IBM System/23 Datamaster's display system, and was intended to support business and word processing use with its sharp, high-resolution characters. Each character is rendered in a box of 9 × 14 pixels, of which 7 × 11 depicts the character itself and the other pixels provide space between character columns and lines. Some characters, such as the lowercase "m", are rendered eight pixels across.
The theoretical total screen display resolution of the MDA is 720 × 350 pixels, if the dimensions of all character cells are added up, but the MDA cannot address individual pixels to take full advantage of this resolution. Each character cell can be set to one of 256 bitmap characters stored in ROM on the card, and this character set cannot be altered from the built-in hardware code page 437. The only way to simulate "graphics" is through ASCII art, obtaining a low resolution 80 × 25 "pixels" screen, based on character positions.
Code page 437 has 256 characters (0-255), including the standard 95 printable ASCII characters from (32-126), and the 33 ASCII control codes (0-31 and 127) are replaced with printable graphic symbols. It also includes another 128 characters (128-255) like the aforementioned characters for drawing forms. Some of these shapes appear in
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https://en.wikipedia.org/wiki/Broxyquinoline
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Broxyquinoline is an antiprotozoal agent.An association with exercise intolerance has been reported.
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https://en.wikipedia.org/wiki/ESlick
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The eSlick is a discontinued e-book reader, an electronic book (e-book) reading device developed by Foxit Software. It has a 6-inch E Ink screen, 600x800 pixel resolution with 4-level gray scale and a mass of 180 g. The device supports text and PDF format for reading and includes Foxit's PDF Creator and Reader Pro Pack software. In August 2010, Foxit announced that it would stop further development of the eSlick and focus on licensing PDF software to the makers of other e-book hardware.
Wired attributed the move to a price war between Amazon.com's Kindle and Barnes & Noble's Nook which undermined Foxit's claim to offer the cheapest e-book reader on the market. Foxit dropped its support completely and abruptly in 2010, completely deleting all references to the eSlick from its site, including numerous forum threads and all firmware updates. This action has alienated and angered many users, as the solutions to many problems were readily available in these threads.
The device is notable in that it has minimal features (no wireless, no subscription). It can read books in secure eReader format but does not support any other DRM formats.
Specifications
Size: 188 x 118 x 9.2 mm (7.4" x 4.7" x 0.4")
Weight: 180 g (6.4 oz)
Display:
size: 15.5 cm (6 in) diagonal (approx 1/4 area of letter-sized page)
resolution: 600 x 800 pixel resolution, 4-level gray scale
Memory: 512 MB standard (100 eBooks at 1.2 MB each average), SD card expansion up to 4 GB Includes 2GB SD card
Rechargeable Lithium-ion battery
PC Interface: USB port
OS: Embedded Linux
Formats supported
As of Firmware 2.0 Build 1130:
Documents: PDF, TXT, ePUB, eReader format, non-encryped and secure PDB
Images: GIF, BMP, JPEG, and PNG
DRM-free Audio: MP3
Operating systems
Windows
The eSlick comes bundled with the proprietary Foxit Reader Pro Pack, PDF Creator, PDF Editor (trial) and PDF Page Organizer Pro (trial).
Updating the reader's firmware is done via a proprietary program (eSlick Update Setup Pac
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https://en.wikipedia.org/wiki/Strongly%20positive%20bilinear%20form
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A bilinear form, a(•,•) whose arguments are elements of normed vector space V is a strongly positive bilinear form if and only if there exists a constant, c>0, such that
for all where is the norm on V.
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https://en.wikipedia.org/wiki/LM13700
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The LM13700 is an integrated circuit consisting of two current controlled operational transconductance amplifiers (OTA), each having differential inputs and a push-pull output. The LM13700 is like a standard op-amp: each has a pair of differential inputs and a single output, but an OTA is voltage in and current out rather than voltage in and voltage out; and OTAs are programmable via the IABC pin. Linearizing diodes at the input reduce distortion and allow increased input levels. The darlington output buffers provided are specifically designed to complement the wide dynamic range of the OTA. This chip is very useful in audio electronics especially in analog synthesizer circuits like voltage controlled oscillators, voltage controlled filters, and voltage controlled amplifiers. The darlington output buffers on the LM13700 are different from those on the LM13600 in that their bias currents (and hence their output DC levels) are independent of IABC pin. This may result in performance superior to that of the LM13600 in audio applications.
See also
Transconductance
Operational amplifier
Transconductance amplifier
current mirror
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https://en.wikipedia.org/wiki/Pickled%20herring
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Pickled herring is a traditional way of preserving herring as food by pickling or curing.
Most cured herring uses a two-step curing process: it is first cured with salt to extract water; then the salt is removed and the herring is brined in a vinegar, salt, and sugar solution, often with peppercorn, bay leaves, raw onions, and so on. Additional flavourings include sherry, mustard and dill, while other non-traditional ingredients have also begun being included in recent years.
Pickled herring remains a popular food or ingredient to dishes in many parts of Europe including Scandinavia, Great Britain, the Baltic, Eastern and Central Europe, as well as the Netherlands. It is also popular in parts of Canada such as British Columbia and Newfoundland. It is also associated with Ashkenazi Jewish cuisine, becoming a staple at kiddushes and social gatherings. Pickled herring is one of the twelve dishes traditionally served at Christmas Eve in Russia, Poland, Lithuania, and Ukraine. Pickled herring is also eaten at the stroke of midnight on New Year's Eve to symbolize a prosperous New Year in Poland, the Czech Republic, Germany, and parts of Scandinavia.
History
Pickled herrings have been a staple in Northern Europe since medieval times, being a way to store and transport fish, especially necessary in meatless periods like Lent. The herrings would be prepared, then packed in barrels for storage or transportation. In 1801 Dutch fishermen amongst the prisoners of war in the Norman Cross Prison were sent to Scotland to teach the Scottish herring fishermen how to cure fish using the Dutch method.
Geographic distribution
In the Nordic countries, once the pickling process is finished and depending on which of the dozens of herring flavourings (mustard, onion, garlic, lingonberries etc.) are selected, it is eaten with dark rye bread, crisp bread, sour cream, or potatoes. This dish is common at Christmas, Easter and Midsummer, where it is frequently accompanied by spirits like ak
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https://en.wikipedia.org/wiki/Nick%20Holonyak
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Nick Holonyak Jr. ( ; November 3, 1928September 18, 2022) was an American engineer and educator. He is noted particularly for his 1962 invention and first demonstration of a semiconductor laser diode that emitted visible light. This device was the forerunner of the first generation of commercial light-emitting diodes (LEDs). He was then working at a General Electric Company research laboratory near Syracuse, New York. He left General Electric in 1963 and returned to his alma mater, the University of Illinois at Urbana-Champaign, where he later became John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics.
Early life and career
Nick Holonyak Jr. was born in Zeigler, Illinois, on November 3, 1928. His parents were Rusyn immigrants. His father worked in a coal mine. Holonyak was the first member of his family to receive any type of formal schooling. He once worked 30 straight hours on the Illinois Central Railroad before realizing that a life of hard labor was not what he wanted and he would prefer to go to school instead. According to a Chicago Tribune article in 2003, "The cheap and reliable semiconductor lasers critical to DVD players, bar code readers and scores of other devices owe their existence in some small way to the demanding workload thrust upon Downstate railroad crews decades ago."
Holonyak earned his bachelor's (1950), master's (1951), and doctoral (1954) degrees in electrical engineering from the University of Illinois at Urbana-Champaign. Holonyak was John Bardeen's first doctoral student there. In 1954, Holonyak went to Bell Telephone Laboratories, where he worked on silicon-based electronic devices. From 1955 to 1957 he served with the U.S. Army Signal Corps.
From 1957 to 1963 he was a scientist at the General Electric Company's Advanced Semiconductor Laboratory near Syracuse, New York. Here he invented, fabricated, and demonstrated the first visible light laser diode on October 9, 1962. He grew crystals of the alloy GaAs0.
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https://en.wikipedia.org/wiki/Wilhelm%20Jordan%20%28geodesist%29
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Wilhelm Jordan (1 March 1842, Ellwangen, Württemberg – 17 April 1899, Hanover) was a German geodesist who conducted surveys in Germany and Africa and founded the German geodesy journal.
Biography
Jordan was born in Ellwangen, a small town in southern Germany. He studied at the polytechnic institute in Stuttgart and after working for two years as an engineering assistant on the preliminary stages of railway construction he returned there as an assistant in geodesy. In 1868, when he was 26 years old, he was appointed a full professor at Karlsruhe. In 1874 Jordan took part in the expedition of Friedrich Gerhard Rohlfs to Libya. From 1881 until his death he was professor of geodesy and practical geometry at the Technical University of Hannover. He was a prolific writer and his best known work was his Handbuch der Vermessungskunde (Handbook of Geodesy).
He is remembered among mathematicians for the Gauss–Jordan elimination algorithm, with Jordan improving the stability of the algorithm so it could be applied to minimizing the squared error in the sum of a series of surveying observations. This algebraic technique appeared in the third edition (1888) of his Textbook of Geodesy.
Wilhelm Jordan is not to be confused with the French mathematician Camille Jordan (Jordan curve theorem), nor with the German physicist Pascual Jordan (Jordan algebras).
Gauss–Jordan elimination
Evidence suggests that B.-I. Clasen also developed the Gauss–Jordan elimination method (independently from Jordan), and both published the method in 1888. Carl Friedrich Gauss did not directly contribute to either derivation.
Notes
External links
English translation of Handbuch der Vermessungskunde, 8th edition, Vol. 1
English translation of Handbuch der Vermessungskunde, 8th edition, Vol. 3, 1st half
English translation of Handbuch der Vermessungskunde, 8th edition, Vol. 3, 2nd half
1842 births
1899 deaths
People from Ellwangen
German geodesists
19th-century German mathematicians
Linear alge
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https://en.wikipedia.org/wiki/Open%20rate
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There are two types of "open rates" one for electronic mail (aka e-mail; see below) and one for physical mail (aka snail mail via the USPS or other physical mail carrier).
Email Open Rate
The email open rate is a measure primarily used by marketers as an indication of how many people "view" or "open" the commercial electronic mail they send out. It is most commonly expressed as a percentage and calculated by dividing the number of email messages opened by the total number of email messages sent (excluding those that bounced.)
Some Email Service Providers (ESP) also track unique email opens. Similar to an email open, unique email opens eliminate all duplicate opens that occur.
Tracking Email Open Rates are typically tracked using a transparent 1x1 pixel, or small transparent tracking image, that is embedded in outgoing emails. When the client or browser used to display the email requests that image, then an "open" is recorded for that email by the image's host server. The email will not be counted as an open until one of the following occurs:
The recipient enables the images in the email or
The recipient interacts with the email by clicking on a link
The open rate of any given email can vary based on a number of variables. For example, the type of industry the email is being sent to. In addition, the day and time an email is scheduled or sent to recipients can have an effect on email open rate. The length of an email's subject line can also affect whether or not it is opened.
Tracking Concerns Open rates is one of the earliest metrics applied in email marketing, but its continued use has become controversial due to conflicting views on its usefulness.
The open rate for an email sent to multiple recipients is then most often calculated as the total number of “opened” emails, expressed as a percentage of the total number of emails sent or—more usually—delivered. The number delivered is itself measured as the number of emails sent out minus the number of bou
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https://en.wikipedia.org/wiki/Investigations%20in%20Mathematics%20Learning
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Investigations in Mathematics Learning is the official research journal of the Research Council for Mathematics Learning. RCML seeks to stimulate, generate, coordinate, and disseminate research efforts designed to understand and/or influence factors that affect mathematics learning.
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https://en.wikipedia.org/wiki/CloudMinds
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CloudMinds is an operator of cloud-based systems for cognitive robotics.
History
CloudMinds was founded in 2015 and is backed by SoftBank, Foxconn, Walden Venture Investments, and Keytone Ventures. CloudMinds has developed research in smart devices, robot control, high-speed security networks, and cloud intelligence integration. CloudMinds developed the Mobile Intranet Cloud Services (MCS) based on these technologies in order to increase the information security of the cloud robot remote control. The technology has been applied in the fields of finance, medicine, the military, public safety, and large-scale manufacturing.
U.S. sanctions
In May 2020, CloudMinds was added to the Bureau of Industry and Security's Entity List due to U.S. national security concerns.
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https://en.wikipedia.org/wiki/Censorship%20of%20GitHub
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GitHub has been the target of censorship from governments using methods ranging from local Internet service provider blocks, intermediary blocking using methods such as DNS hijacking and man-in-the-middle attacks, and denial-of-service attacks on GitHub's servers from countries including China, India, Iraq, and Russia. In all of these cases, GitHub has been eventually unblocked after backlash from users and technology businesses or compliance from GitHub.
Background
GitHub is a web-based Git repository hosting service and is primarily used to host the source code of software, facilitate project management, and provide distributed revision control functionality of Git, access control, wikis, and bug tracking. As of June 2023, GitHub reports having over 100 million users and over 330 million repositories. It offers free accounts, a pastebin service called Gist, and free website hosting under its github.io domain. The GitHub terms of service prohibits illegal use and it reserves the right to remove content at its discretion. Users can fork (copy and individually develop) other projects, which GitHub does not automatically take down when served DMCA takedown notices. GitHub uses HTTPS for its connections, making data more secure against interception from third parties.
China
China heavily regulates Internet traffic and has blocked many international Internet companies including Facebook and Twitter. In addition, Western businesses have said that these restrictions hurt their business by reducing access to information, such as from search engines and those using VPNs. In 2013, the country started blocking GitHub and it was met by protests among Chinese programmers.
GreatFire, a Chinese anti-censorship organization, has attempted to circumvent the Great Firewall of China using mirror websites. However, the links to these pages were posted using GitHub which brings the risk of the site being blocked along with the mirrors. In a previous incident, HSBC bank's Chinese
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https://en.wikipedia.org/wiki/Wooded%20meadow
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Wooded meadows (also named wood-meadows, park meadows, etc.) are ecosystems in temperate forest regions. They are sparse natural stands with a regularly mowed herbaceous layer.
While frequent throughout Europe during the Medieval period and before, wooded meadows have largely disappeared. Wooded meadows originated with the practices of hunter-gatherer communities. They were important in terms of social organization around a natural resource and determined much of the community's interactions with the natural world. In the early 20th century, wooded meadows were used for fruit cultivation in Sweden; however, their prevalence has decreased substantially due to changes in land management and a movement toward more intensive types of agroecosystems. The more typical, calcicolous wooded meadows are common around the Baltic Sea.
Wooded meadows have high species richness. In some of the current Estonian wooded meadows, world-record species densities have been recorded (up to 76 species of vascular plants per square meter).
Literature
Kull, Kalevi; Kukk, Toomas; Lotman, Aleksei 2003. When culture supports biodiversity: The case of wooded meadow. In: Roepstorff, Andreas; Bubandt, Nils; Kull, Kalevi (eds.) 2003. Imagining Nature: Practices of Cosmology and Identity. Aarhus: Aarhus University Press, 76–96. (pdf)
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https://en.wikipedia.org/wiki/Kamusi%20project
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The Kamusi Project is a cooperative online dictionary which aims to produce dictionaries and other language resources for every language, and to make those resources available free to everyone. Users can register and add content. "" is the Swahili word for dictionary. It belongs to Kamusi Project International based in Geneva.
The project was started in 1994 at the Council on African Studies at Yale University (United States) as an online dictionary of the Swahili language under the name of the "Internet Living Swahili Dictionary" by its founder and present director Martin Benjamin. Since restructuring in 2014 the Swahili vocabulary is no more accessible.
In 2007 the project spun off from Yale. Since 2009 it has been run jointly by Kamusi Project International, a non profit association registered in Geneva, Switzerland, and Kamusi Project USA, a 501(c)(3) organization. From 2013 through 2017, it also had an academic base at the Distributed Information Systems Laboratory at EPFL in Lausanne.
Since 2010 programming and the Swahili-English database have been expanded to incorporate other languages. Kamusi project is open to build interconnected dictionaries for all existing languages. The project was knocked offline for a year beginning in mid-2015 when its server was unable to handle the data load for expanding to multiple languages. After reprogramming within a graph database paradigm, service was restored and opened to many new languages in 2016, though conversion of the original Swahili data to the new system continues to languish due to lack of funds.
Kamusi was recognized by the Obama administration as a launch partner in the White House Big Data Initiative in 2013.
In 2017, the project began an experimental technical development wing called Kamusi Labs that grows the project through volunteer internship projects with students from universities around the world.
In 2017 the project distributed more than 60,000 entries between Swahili and English via a mobil
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https://en.wikipedia.org/wiki/Calcium%20deficiency%20%28plant%20disorder%29
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Calcium (Ca) deficiency is a plant disorder that can be caused by insufficient level of biologically available calcium in the growing medium, but is more frequently a product of low transpiration of the whole plant or more commonly the affected tissue. Plants are susceptible to such localized calcium deficiencies in low or non-transpiring tissues because calcium is not transported in the phloem. This may be due to water shortages, which slow the transportation of calcium to the plant, poor uptake of calcium through the stem, or too much nitrogen in the soil.
Causes
Acidic, sandy, or coarse soils often contain less calcium. Uneven soil moisture and overuse of fertilizers can also cause calcium deficiency. At times, even with sufficient calcium in the soil, it can be in an insoluble form and is then unusable by the plant or it could be attributed to a "transport protein". Soils containing high phosphorus are particularly susceptible to creating insoluble forms of calcium.
Calcium and magnesium are opposed within the plant cells, and have antagonistic interactions. As a result, a homeostatic balance between Ca and Mg within the plant is necessary for optimal growth and proper development.
Symptoms
Calcium deficiency symptoms appear initially as localized tissue necrosis leading to stunted plant growth, necrotic leaf margins on young leaves or curling of the leaves, and eventual death of terminal buds and root tips. Generally, the new growth and rapidly growing tissues of the plant are affected first. The mature leaves are rarely if ever affected because calcium accumulates to high concentrations in older leaves. Calcium deficiencies in plants are associated with reduced height, fewer nodes, and less leaf area.
Crop-specific symptoms include:
Apple 'Bitter pit' – fruit skins develop pits, brown spots appear on skin and/or in flesh and taste of those areas is bitter. This usually occurs when fruit is in storage, and Bramley apples are particularly susceptible. R
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https://en.wikipedia.org/wiki/Consistency%20model
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In computer science, a consistency model specifies a contract between the programmer and a system, wherein the system guarantees that if the programmer follows the rules for operations on memory, memory will be consistent and the results of reading, writing, or updating memory will be predictable. Consistency models are used in distributed systems like distributed shared memory systems or distributed data stores (such as filesystems, databases, optimistic replication systems or web caching). Consistency is different from coherence, which occurs in systems that are cached or cache-less, and is consistency of data with respect to all processors. Coherence deals with maintaining a global order in which writes to a single location or single variable are seen by all processors. Consistency deals with the ordering of operations to multiple locations with respect to all processors.
High level languages, such as C++ and Java, maintain the consistency contract by translating memory operations into low-level operations in a way that preserves memory semantics, reordering some memory instructions, and encapsulating required synchronization with library calls such as pthread_mutex_lock().
Example
Assume that the following case occurs:
The row X is replicated on nodes M and N
The client A writes row X to node M
After a period of time t, client B reads row X from node N
The consistency model determines whether client B will definitely see the write performed by client A, will definitely not, or cannot depend on seeing the write.
Types
Consistency models define rules for the apparent order and visibility of updates, and are on a continuum with tradeoffs. There are two methods to define and categorize consistency models; issue and view.
Issue Issue method describes the restrictions that define how a process can issue operations.
View View method which defines the order of operations visible to processes.
For example, a consistency model can define that a process is not
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https://en.wikipedia.org/wiki/Fuzzy%20measure%20theory
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In mathematics, fuzzy measure theory considers generalized measures in which the additive property is replaced by the weaker property of monotonicity. The central concept of fuzzy measure theory is the fuzzy measure (also capacity, see ), which was introduced by Choquet in 1953 and independently defined by Sugeno in 1974 in the context of fuzzy integrals. There exists a number of different classes of fuzzy measures including plausibility/belief measures, possibility/necessity measures, and probability measures, which are a subset of classical measures.
Definitions
Let be a universe of discourse, be a class of subsets of , and . A function where
is called a fuzzy measure.
A fuzzy measure is called normalized or regular if .
Properties of fuzzy measures
A fuzzy measure is:
additive if for any such that , we have ;
supermodular if for any , we have ;
submodular if for any , we have ;
superadditive if for any such that , we have ;
subadditive if for any such that , we have ;
symmetric if for any , we have implies ;
Boolean if for any , we have or .
Understanding the properties of fuzzy measures is useful in application. When a fuzzy measure is used to define a function such as the Sugeno integral or Choquet integral, these properties will be crucial in understanding the function's behavior. For instance, the Choquet integral with respect to an additive fuzzy measure reduces to the Lebesgue integral. In discrete cases, a symmetric fuzzy measure will result in the ordered weighted averaging (OWA) operator. Submodular fuzzy measures result in convex functions, while supermodular fuzzy measures result in concave functions when used to define a Choquet integral.
Möbius representation
Let g be a fuzzy measure. The Möbius representation of g is given by the set function M, where for every ,
The equivalent axioms in Möbius representation are:
.
, for all and all
A fuzzy measure in Möbius representation M is called normalized
if
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https://en.wikipedia.org/wiki/Software%20factory%20%28Microsoft%20.NET%29
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Implementations
The Enterprise Framework Factory (the EFx Factory) from Microsoft Services was one of the first pioneering architectural software factories to use a unique combination of model driven development, and integrated runtime environment tools to build Service-Oriented Enterprise Applications and Services.
EFx Factory Blog
Microsoft Patterns and Practices Team have developed four software factories:
SharePoint Software Factory, for SharePoint 2007/2010 and Visual Studio 2008/2010
Smart Client Software Factory, for Visual Studio 2008 (released: April 2008)
Web Service Software Factory (released: July 2006, updated December 2006, 2010, a new Service Factory : Modeling Edition version (incompatible with the previous ones) released on November 2007)
Mobile Client Software Factory (released: July 2006)
Project Glidepath is a Micro ISV-oriented Software Factory, also from Microsoft.
Project Glidepath Blog
Project Glidepath Forums
NConstruct is Windows and Web rapid enterprise application development tool and environment for .NET Framework environment.
See also
EFx Factory .net factory
Software Product Line
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https://en.wikipedia.org/wiki/Whispering%20gallery
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A whispering gallery is usually a circular, hemispherical, elliptical or ellipsoidal enclosure, often beneath a dome or a vault, in which whispers can be heard clearly in other parts of the gallery. Such galleries can also be set up using two parabolic dishes. Sometimes the phenomenon is detected in caves.
Theory
A whispering gallery is most simply constructed in the form of a circular wall, and allows whispered communication from any part of the internal side of the circumference to any other part. The sound is carried by waves, known as whispering-gallery waves, that travel around the circumference clinging to the walls, an effect that was discovered in the whispering gallery of St Paul's Cathedral in London. The extent to which the sound travels at St Paul's can also be judged by clapping in the gallery, which produces four echoes. Other historical examples are the Gol Gumbaz mausoleum in Bijapur, India and the Echo Wall of the Temple of Heaven in Beijing. A hemispherical enclosure will also guide whispering gallery waves. The waves carry the words so that others will be able to hear them from the opposite side of the gallery.
The gallery may also be in the form of an ellipse or ellipsoid, with an accessible point at each focus. In this case, when a visitor stands at one focus and whispers, the line of sound emanating from this focus reflects directly to the focus at the other end of the gallery, where the whispers may be heard. In a similar way, two large concave parabolic dishes, serving as acoustic mirrors, may be erected facing each other in a room or outdoors to serve as a whispering gallery, a common feature of science museums. Egg-shaped galleries, such as the Golghar Granary at Bankipore, and irregularly shaped smooth-walled galleries in the form of caves, such as the Ear of Dionysius in Syracuse, also exist.
Examples
India
The Gol Gumbaz in Bijapur, India.
The Golghar Granary in Bankipore, India.
The Victoria Memorial in Kolkata.
United Kingd
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https://en.wikipedia.org/wiki/Letter%20board
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A letter board may refer to two devices.
Types of letter boards
Marquee
A letter board or letter sign, also known as marquee, is a customizable form of signage that employs individually movable letters of the alphabet. They are used by, e.g., movie theaters to list the current roster of films, churches to display the titles of sermons, and other buildings, people, and institutions whose signs are required to change on a regular basis.
Communication Board
A letter board, or communication board, refers to a device used to supplement verbal communication. Communication boards can be as basic as letters of the alphabet or contain extensive options of words, phrases, pictures, and symbols of common items or actions. These boards are multimodal and may be digital or analog. Individuals with speech and language impairments or non-verbal communicators may use communication boards depending on their degree of gross motor skills.
Augmentative and alternative communication (AAC) aids are utilized by individuals who experience congenital disabilities, such as autism spectrum disorder, cerebral palsy, developmental disabilities, intellectual disabilities, developmental apraxia of speech and genetic disorders, and acquired disabilities, including amyotrophic lateral sclerosis, cerebrovascular disease, glossectomy, laryngectomy, primary progressive aphasia, supranuclear palsy, and traumatic brain injuries.
Forms of Communication Aid
AAC can be divided into different categories, but are most commonly categorized as unaided or aided. These forms of communication can also be analog or digital.
Unaided
Unaided forms of augmented communication do not require any external tools or aid to communicate. This form of AAC requires fine motor skills. When a person uses unaided AAC they are relying solely on their body to communicate. These are non-technological forms of expression, such as facial expressions, body language, and facial gestures. Sign language is the primary example
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https://en.wikipedia.org/wiki/English%20Electric%20DEUCE
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The DEUCE (Digital Electronic Universal Computing Engine) was one of the earliest British commercially available computers, built by English Electric from 1955. It was the production version of the Pilot ACE, itself a cut-down version of Alan Turing's ACE.
Hardware description
The DEUCE had 1450 thermionic valves, and used mercury delay lines for its main memory; each of the 12 delay lines could store 32 instructions or data words of 32 bits each. It adopted the then high 1 megahertz clock rate of the Pilot ACE. Input/output was via Hollerith 80-column punch-card equipment. The reader read cards at the rate of 200 per minute, while the card punch rate was 100 cards per minute. The DEUCE also had an 8192-word magnetic drum for main storage. To access any of the 256 tracks of 32 words, the drum had one group of 16 read and one group of 16 write heads, each group on independent moveable arms, each capable of moving to one of 16 positions. Access time was 15 milliseconds if the heads were already in position; an additional 35 milliseconds was required if the heads had to be moved. There was no rotational delay incurred when reading from and writing to drum. Data was transferred between the drum and one of the 32-word delay lines.
The DEUCE could be fitted with paper tape equipment; the reader speed was 850 characters per second, while the paper tape output speed was 25 characters per second. (The DEUCE at the University of New South Wales {UTECOM} had a Siemens M100 teleprinter attached in 1964, giving 10 characters per second input/output). Decca magnetic tape units could also be attached. The automatic multiplier and divider operated asynchronously (that is, other instructions could be executed while the multiplier/divider unit was in operation). Two arithmetic units were provided for integer operations: one of 32 bits and another capable of performing 32-bit operations and 64-bit operations. Auto-increment and auto-decrement were provided on eight registers fro
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https://en.wikipedia.org/wiki/Colortrak%202000
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Colortrak 2000 was a brand name used for RCA's high-end television models produced from the early-1980s to the early 1990s. Colortrak 2000 was situated above the less expensive Colortrak line, but below the more expensive Dimensia line. As opposed to ColorTrak, ColorTrak 2000 models incorporated a comb filter, which provided a sharper picture. The Colortrak 2000 chassis was identical to the Dimensia tabletop model. Colortrak 2000s with BNC connectors were given the designation of Lyceum TVs. This TV set was also used with RCA's Digital Command Component System released in 1985.
Features
Colortrak 2000s had a wide array of high-end features such as a large input/output panel on the back, which included BNC connections, and advanced video features. The Colortrak 2000s from 1983 and later came with the Digital Command Center, a large and very advanced remote control. The same remote was also used for all the Dimensias, except it was called Dimensia Intelligent Audio Video.
See also
RCA Dimensia
Lyceum TV
Digital Command Center
Colortrak
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https://en.wikipedia.org/wiki/Mediated%20VPN
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A mediated VPN is a virtual private network topology where two or more participants connect to a central switchboard server managed typically by a third party in order to create a virtual private network between them, as distinct from a typical VPN arrangement whereby clients of an organisation connect to a VPN concentrator managed by the same organization.
Typically a switchboard server (referred to as a mediator) will manage several VPNs, identifying each individually by authentication credentials (such as username, network name and passwords). The mediator's role is to assign IP addresses to each participant in a VPN, and to encrypt data through the switchboard server in order to keep it secure from other participants in other VPNs.
See also
Virtual private network
Virtual Private LAN Service
Point-to-point (telecommunications)
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https://en.wikipedia.org/wiki/Deep%20parotid%20lymph%20nodes
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The deep parotid lymph nodes are lymph nodes found below the parotid gland.
The afferents of the subparotid glands drain the nasal part of the pharynx and the posterior parts of the nasal cavities.
Their efferents pass to the superior deep cervical glands.
Additional images
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https://en.wikipedia.org/wiki/Ralph-Johan%20Back
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Ralph-Johan Back is a Finnish computer scientist. Back originated the refinement calculus, an important approach to the formal development of programs using stepwise refinement, in his 1978 PhD thesis at the University of Helsinki, On the Correctness of Refinement Steps in Program Development. He has undertaken much subsequent research in this area. He has held positions at CWI Amsterdam, the Academy of Finland and the University of Tampere.
Since 1983, he has been Professor of Computer Science at the Åbo Akademi University in Turku. For 2002–2007, he was an Academy Professor at the Academy of Finland. He is Director of CREST (Center for Reliable Software Technology) at Åbo Akademi.
Back is a member of Academia Europaea.
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https://en.wikipedia.org/wiki/Topfield%20Application%20Program
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A Topfield Application Program (TAP) is a software application which extends the standard functionality of the Topfield products designed for digital TV. Examples of TAPs are electronic programme guides, digital photo viewers and MP3 players.
Anyone with the necessary computer programming skills may create a TAP to meet their needs. This is possible because Topfield have specified an open (or public) API which allows TAPs to be created using the C or C++ programming languages. They can be installed into most Topfield PVR models.
Some people have created TAPs and made them available for others to download and use, either free of charge or for a small fee. There are several internet forums dedicated to TAPs where information and support can be exchanged.
External links
TAPWorld: The most complete Topfield TAP directory (not currently Active but in the process of coming back online - June 2013)
UK directory of TAPs
Digital video recorders
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https://en.wikipedia.org/wiki/Muton%20%28genetics%29
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Muton is a term in genetics that means the smallest unit in a chromosome that can be changed by mutations.
The term Muton was created by Seymour Benzer in 1955 after his work about the mapping of bacteriophages T4.
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https://en.wikipedia.org/wiki/Elimination%20theory
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In commutative algebra and algebraic geometry, elimination theory is the classical name for algorithmic approaches to eliminating some variables between polynomials of several variables, in order to solve systems of polynomial equations.
Classical elimination theory culminated with the work of Francis Macaulay on multivariate resultants, as described in the chapter on Elimination theory in the first editions (1930) of Bartel van der Waerden's Moderne Algebra. After that, elimination theory was ignored by most algebraic geometers for almost thirty years, until the introduction of new methods for solving polynomial equations, such as Gröbner bases, which were needed for computer algebra.
History and connection to modern theories
The field of elimination theory was motivated by the need of methods for solving systems of polynomial equations.
One of the first results was Bézout's theorem, which bounds the number of solutions (in the case of two polynomials in two variables at Bézout time).
Except for Bézout's theorem, the general approach was to eliminate variables for reducing the problem to a single equation in one variable.
The case of linear equations was completely solved by Gaussian elimination, where the older method of Cramer's rule does not proceed by elimination, and works only when the number of equations equals the number of variables. In the 19th century, this was extended to linear Diophantine equations and abelian group with Hermite normal form and Smith normal form.
Before the 20th century, different types of eliminants were introduced, including resultants, and various kinds of discriminants. In general, these eliminants are also invariant under various changes of variables, and are also fundamental in invariant theory.
All these concepts are effective, in the sense that their definitions include a method of computation. Around 1890, David Hilbert introduced non-effective methods, and this was seen as a revolution, which led most algebraic geomet
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https://en.wikipedia.org/wiki/Deep%20venous%20palmar%20arch
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The deep palmar arch, an arterial network is accompanied by a pair of venae comitantes which constitute the deep venous palmar arch. It receives the veins corresponding to the branches of the arterial arch: the palmar metacarpal veins.
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https://en.wikipedia.org/wiki/Clofoctol
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Clofoctol is a bacteriostatic antibiotic. It is used in the treatment of respiratory tract and ear, nose and throat infections caused by Gram-positive bacteria.
It has been marketed in France till 2005 under the trade name Octofene and in Italy as Gramplus.
It is only functional against Gram-positive bacteria.
It penetrates into human lung tissue.
Apteeus is developing clofoctol as a potential therapy against SARS-CoV-2.
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https://en.wikipedia.org/wiki/Instruction%20pipelining
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In computer engineering, instruction pipelining is a technique for implementing instruction-level parallelism within a single processor. Pipelining attempts to keep every part of the processor busy with some instruction by dividing incoming instructions into a series of sequential steps (the eponymous "pipeline") performed by different processor units with different parts of instructions processed in parallel.
Concept and motivation
In a pipelined computer, instructions flow through the central processing unit (CPU) in stages. For example, it might have one stage for each step of the von Neumann cycle: Fetch the instruction, fetch the operands, do the instruction, write the results. A pipelined computer usually has "pipeline registers" after each stage. These store information from the instruction and calculations so that the logic gates of the next stage can do the next step.
This arrangement lets the CPU complete an instruction on each clock cycle. It is common for even-numbered stages to operate on one edge of the square-wave clock, while odd-numbered stages operate on the other edge. This allows more CPU throughput than a multicycle computer at a given clock rate, but may increase latency due to the added overhead of the pipelining process itself. Also, even though the electronic logic has a fixed maximum speed, a pipelined computer can be made faster or slower by varying the number of stages in the pipeline. With more stages, each stage does less work, and so the stage has fewer delays from the logic gates and could run at a higher clock rate.
A pipelined model of computer is often the most economical, when cost is measured as logic gates per instruction per second. At each instant, an instruction is in only one pipeline stage, and on average, a pipeline stage is less costly than a multicycle computer. Also, when made well, most of the pipelined computer's logic is in use most of the time. In contrast, out of order computers usually have large amounts of idl
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https://en.wikipedia.org/wiki/Phantom%20reference
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A phantom reference is a kind of reference in Java, where the memory can be reclaimed. The phantom reference is one of the strengths or levels of 'non strong' reference defined in the Java programming language; the others being weak and soft. Phantom reference are the weakest level of reference in Java; in order from strongest to weakest, they are: strong, soft, weak, phantom.
An object is phantomly referenced after it has been finalized.
In Java 8 and earlier versions, the reference needs to be cleared before the memory for a finalized referent can be reclaimed. A change in Java 9 will allow memory from a finalized referent to be reclaimable immediately.
Use
Phantom references are of limited use, primarily narrow technical uses. First, it can be used instead of a finalize method, guaranteeing that the object is not resurrected during finalization. This allows the object to be garbage collected in a single cycle, rather than needing to wait for a second GC cycle to ensure that it has not been resurrected. A second use is to detect exactly when an object has been removed from memory (by using in combination with a ReferenceQueue object), ensuring that its memory is available, for example deferring allocation of a large amount of memory (e.g., a large image) until previous memory is freed.
See also
Ephemeron
Weak reference
Soft reference
Circular reference
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https://en.wikipedia.org/wiki/Elliptic%20function
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In the mathematical field of complex analysis, elliptic functions are a special kind of meromorphic functions, that satisfy two periodicity conditions. They are named elliptic functions because they come from elliptic integrals. Originally those integrals occurred at the calculation of the arc length of an ellipse.
Important elliptic functions are Jacobi elliptic functions and the Weierstrass -function.
Further development of this theory led to hyperelliptic functions and modular forms.
Definition
A meromorphic function is called an elliptic function, if there are two -linear independent complex numbers such that
and .
So elliptic functions have two periods and are therefore doubly periodic functions.
Period lattice and fundamental domain
If is an elliptic function with periods it also holds that
for every linear combination with .
The abelian group
is called the period lattice.
The parallelogram generated by and
is a fundamental domain of acting on .
Geometrically the complex plane is tiled with parallelograms. Everything that happens in one fundamental domain repeats in all the others. For that reason we can view elliptic function as functions with the quotient group as their domain. This quotient group, called an elliptic curve, can be visualised as a parallelogram where opposite sides are identified, which topologically is a torus.
Liouville's theorems
The following three theorems are known as Liouville's theorems (1847).
1st theorem
A holomorphic elliptic function is constant.
This is the original form of Liouville's theorem and can be derived from it. A holomorphic elliptic function is bounded since it takes on all of its values on the fundamental domain which is compact. So it is constant by Liouville's theorem.
2nd theorem
Every elliptic function has finitely many poles in and the sum of its residues is zero.
This theorem implies that there is no elliptic function not equal to zero with exactly one pole of order on
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https://en.wikipedia.org/wiki/Branching%20order%20of%20bacterial%20phyla%20%28Woese%2C%201987%29
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There are several models of the Branching order of bacterial phyla, one of these was proposed in 1987 paper by Carl Woese.
The branching order proposed by Carl Woese was based on molecular phylogeny, which was considered revolutionary as all preceding models were based on discussions of morphology. (v. Monera). Several models have been proposed since and no consensus is reached at present as to the branching order of the major bacterial lineages.
The gene used was the 16S ribosomal DNA.
Tree
The names have been changed to reflect more current nomenclature used by molecular phylogenists.
Note on names
Despite the impact of the paper on bacterial classification, it was not a proposal for change of taxonomy. Consequently, many clades were given official names. Only subsequently, this occurred: for example, the "purple bacteria and relatives" were renamed Proteobacteria.
Discussion
In 1987, Carl Woese, regarded as the forerunner of the molecular phylogeny revolution, divided Eubacteria into 11 divisions based on 16S ribosomal RNA (SSU) sequences, listed below. Many new phyla have been proposed since then.
Purple Bacteria and their relatives (later renamed Proteobacteria)
alpha subdivision (purple non-sulfur bacteria, rhizobacteria, Agrobacterium, Rickettsiae, Nitrobacter)
beta subdivision (Rhodocyclus, (some) Thiobacillus, Alcaligenes, Spirillum, Nitrosovibrio)
gamma subdivision (enterics, fluorescent pseudomonads, purple sulfur bacteria, Legionella, (some) Beggiatoa)
delta subdivision (Sulfur and sulfate reducers (Desulfovibrio), Myxobacteria, Bdellovibrio)
Gram-positive Eubacteria
High-G+C species (later renamed Actinobacteria) (Actinomyces, Streptomyces, Arthrobacter, Micrococcus, Bifidobacterium)
Low-G+C species (later renamed Firmicutes) (Clostridium, Peptococcus, Bacillus, Mycoplasma)
Photosynthetic species (Heliobacteria)
Species with Gram-negative walls (Megasphaera, Sporomusa)
Cyanobacteria and chloroplasts (Aphanocapsa, Oscillatoria, Nostoc,
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https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20for%20Ornithology
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The Max Planck Institute for Ornithology was a non-university research institution under the sponsorship of the Max Planck Society for the Advancement of Science (MPG). As of January 1st 2023, it merged with the Max Planck Institute for Neurobiology to form the new Max Planck Institute for Biological Intelligence. The institute is located in Seewiesen, which belongs to the municipality of Pöcking in Upper Bavaria.
The institute’s focus was on basic scientific research in the fields of organismic biology, zoology, ornithology, neurobiology, behavioural ecology, evolutionary biology and evolutionary genetics.
The institute is managed on a collegial basis, i.e. one of the two directors of the institute takes over the management for a certain time period. The last managing director was Manfred Gahr (2020 - 2022).
History and current developments
The Max Planck Institute for Behavioural Physiology was inaugurated in Seewiesen in 1958 under the direction of Erich von Holst and the later Nobel Prize winner Konrad Lorenz. In 1959, the Ornithological station in Radolfzell was attached to the MPI for Behavioral Physiology. Up to this day, the coordination of Bird ringing for South Germany, Austria and Berlin happens in Radolfzell.
The history of the ornithological station in Radolfzell reaches back to the former Rossitten Bird Observatory, which was founded by the German Ornithological Society under Johannes Thienemann in 1901 in what was then East Prussia (today the Rybatschi Bird Observatory). In 1924, the Rossitten Bird Observatory was integrated into the Kaiser Wilhelm Society, moved to Radolfzell in 1946 and incorporated into the Max Planck Society in 1949.
In 1999, the Max Planck Institute for Behavioural Physiology closed down and became the research unit for Ornithology of the Max Planck Society by making the departments of Eberhard Gwinner (Andechs) and Peter Berthold at the ornithological station in Radolfzell independent. In 2004, the research unit turned into
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https://en.wikipedia.org/wiki/Watermark%20%28data%20synchronization%29
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A Watermark for data synchronization describes an object of a predefined format which provides a point of reference value for two systems/datasets attempting to establish delta/incremental synchronization; any object in the queried data source which was created, modified, or deleted after the watermark's value will be qualified as "above watermark" and should be returned to the client requesting data.
This approach allows the client to retrieve only the objects which have changed since the latest watermark, and also enables the client to resume its synchronization job from where it left off in the event of some pause or downtime.
Methodology
Watermark term is often used in Directory Synchronization software development projects. For example, products such as Microsoft Exchange Server, Active Directory, Active Directory Application Mode (ADAM), and Microsoft Identity Integration Server 2003/ Microsoft Identity Lifecycle Manager Server 2007, as well as Cisco Unified Communications Manager or Sun Microsystems IPlanet and other LDAP-based directory products are using DirSync and consequently will consume "watermark" object to provide efficient synchronization between directories. Watermark object sometimes can be referred as "cookie".
DirSync control implementation can differ from product to product, however concept of watermark will allow any product to read changes in the directory incrementally.
See also
Watermark (disambiguation)
Microsoft Active Directory
Microsoft Identity Integration Server
High-water mark (computer security)
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https://en.wikipedia.org/wiki/Magic%20circle
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A magic circle is a circle of space marked out by practitioners of some branches of ritual magic, which they generally believe will contain energy and form a sacred space, or will provide them a form of magical protection, or both. It may be marked physically, drawn in a material like salt, flour, or chalk, or merely visualised.
Techniques
Traditionally, circles are believed by ritual magicians to form a protective barrier between themselves and what they summon. One text known as the Heptameron says of the circle, 'But because the greatest power is attributed to the circles; (for they are certain fortresses to defend the operators safe from the evil spirits); in the first place we will treat concerning the composition of a circle.'
Moreover, as magician and historian Jake Stratton-Kent writes, 'In short a circle is not an obsolete symbol of a superstitious fear of spirits, but an intentionally created ritual space for various purposes. It is not always required for all kinds of ritual work, but neither is it of no value, quite the contrary. Making sacred space is among the most primal of rituals, such intentional actions are as worthy of the term psychoactive as any substance.'
Circles may or may not be physically marked out on the ground, and a variety of elaborate patterns for circle markings can be found in grimoires and magical manuals, often involving angelic and divine names. Such markings, or a simple unadorned circle, may be drawn in chalk or salt, or indicated by other means such as with a cord. Some traditions include tracing or circumambulation.
Uses
In Sumer
The Sumerians called the practice of using ritual circles zisurrû.
In Judaism
Examples of Jewish customs showing the use of the magic circle can be found in the birth protection rituals of Alsace and the surrounding area. As early as 1560, a text by the rabbi Naphtali Hirsch ben Elieser Treves notes a custom in which a circle is drawn around the birthing woman to protect her from Lilith and
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https://en.wikipedia.org/wiki/Abbott%20AxSYM
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The Abbott AxSYM is an immunochemical automated analyzer made by Abbott Laboratories. It is used for serology tests and therapeutic drug monitoring, and uses antibodies to alter the deflection of polarized light. It can also be used to monitor hormone level and some cardiac markers such as troponin.
Appearance and use
Blood samples and reagents are placed in separate carousels on the right of the machine. This instrument is used in medical laboratories by trained medical personnel. It can process about 100 samples an hour.
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https://en.wikipedia.org/wiki/Stanford/ITS%20character%20set
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Stanford/ITS character set is an extended ASCII character set based on SEASCII with modifications allowing compatibility with 1968 ASCII.
Usage
It is used as an alternate character set of the SUPDUP protocol for terminals with %TOSAI and %TOFCI bits set. It is also recommended for TeX implementations on systems with large character sets. The default plain TeX macro package sets values (↑) and (↓) as alternative character codes for superscripts and subscripts, respectively (the default being ^ and _).
The Knight keyboard is an example of a keyboard capable of inputting all of the defined characters excluding ⋅γδ±⊕◊∫, as they are mapped to ASCII commands NUL, HT, LF, FF, CR, ESC and DEL, respectively.
Coverage
Each character is encoded as a single seven-bit code value. It contains all 95 printable ASCII characters along with 27 mathematical symbols and 6 Greek letters.
Code page layout
See also
Stanford Extended ASCII
Incompatible Timesharing System
SUPDUP
TeX
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https://en.wikipedia.org/wiki/Biofilter
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Biofiltration is a pollution control technique using a bioreactor containing living material to capture and biologically degrade pollutants. Common uses include processing waste water, capturing harmful chemicals or silt from surface runoff, and microbiotic oxidation of contaminants in air. Industrial biofiltration can be classified as the process of utilizing biological oxidation to remove volatile organic compounds, odors, and hydrocarbons.
Examples of biofiltration
Examples of biofiltration include:
Bioswales, biostrips, biobags, bioscrubbers, Vermifilters and trickling filters
Constructed wetlands and natural wetlands
Slow sand filters
Treatment ponds
Green belts
Green walls
Riparian zones, riparian forests, bosques
Bivalve bioaccumulation
Control of air pollution
When applied to air filtration and purification, biofilters use microorganisms to remove air pollution.
The air flows through a packed bed and the pollutant transfers into a thin biofilm on the surface of the packing material. Microorganisms, including bacteria and fungi are immobilized in the biofilm and degrade the pollutant. Trickling filters and bioscrubbers rely on a biofilm and the bacterial action in their recirculating waters.
The technology finds the greatest application in treating malodorous compounds and volatile organic compounds (VOCs). Industries employing the technology include food and animal products, off-gas from wastewater treatment facilities, pharmaceuticals, wood products manufacturing, paint and coatings application and manufacturing and resin manufacturing and application, etc. Compounds treated are typically mixed VOCs and various sulfur compounds, including hydrogen sulfide. Very large airflows may be treated and although a large area (footprint) has typically been required—a large biofilter (>200,000 acfm) may occupy as much or more land than a football field—this has been one of the principal drawbacks of the technology. Since the early 1990s, engineered biofil
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https://en.wikipedia.org/wiki/Centenarian
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A centenarian is a person who has reached the age of 100 years. The term is invariably associated with longevity. The United Nations in 2012 estimated that there were 316,600 living centenarians worldwide.
As world population and life expectancy continue to increase, the number of centenarians is expected to increase substantially in the twenty-first century. According to the Office of National Statistics in the United Kingdom, one-third of babies born in the country in 2013 are expected to live to 100.
The United Nations estimates that currently there are 573,000 centenarians, almost quadruple the estimate of 151,000 made in 2000. According to a 1998 United Nations demographic survey, Japan is expected to have 272,000 centenarians by 2050; other sources suggest that the number could be closer to 1 million. The incidence of centenarians in Japan was one per 3,522 people in 2008.
In Japan, the number of centenarians is highly skewed towards females. Japan in fiscal year 2016 had 57,525 female centenarians, while there were 8,167 males, a ratio of 7:1. The increase of centenarians was even more skewed at 11.6:1.
Worldwide incidence by country
The total number of centenarians in the world is uncertain. The Population Division of the United Nations estimated that there were 23,000 in 1950, 110,000 in 1990, 150,000 in 1995, 209,000 in 2000, 324,000 in 2005, 455,000 in 2009 and 573,000 in 2021. However, these older estimates did not take into account downward adjustments of national estimates made by several countries such as the United States. The UN estimated in 2012, as a result of these adjustments, that there were only 316,600 centenarians worldwide. The following table gives estimated centenarian populations by country, including both the latest and the earliest known estimates, where available.
Supercentenarians
A supercentenarian, sometimes hyphenated as super-centenarian, is a person who has reached the age of 110 years. This age milestone is only achieved
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https://en.wikipedia.org/wiki/Gymnogramma%20dealbata
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Gymnogramma dealbata is the name of a plant species. It may refer to:
Pityrogramma dealbata, described in 1825 as Gymnogramma dealbata C.Presl
Argyrochosma dealbata, described in 1859 as Gymnogramma dealbata (Pursh) Nutt. ex Mett.
Ferns
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https://en.wikipedia.org/wiki/Fungal%20fruit%20body%20lectin%20family
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In molecular biology, the fungal fruit body lectin family consists of several fungal fruit body lectin proteins. Fruit body lectins are thought to have insecticidal activity and may also function in capturing nematodes. One member of this family, the lectin XCL from Boletus chrysenteron (formerly Xerocomus chrysenteron), induces drastic changes in the actin cytoskeleton after sugar binding at the cell surface and internalisation, and has potent insecticidal activity. The fold of lectin XCL is not related to any of several other lectin folds, but shows significant structural similarity to cytolysins.
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https://en.wikipedia.org/wiki/Samara%20Reck-Peterson
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Samara Reck-Peterson is an American cell biologist and biophysicist. She is a Professor of Cellular and Molecular Medicine and Cell and Developmental Biology at the University of California, San Diego and an Investigator of the Howard Hughes Medical Institute. She is known for her contributions to our understanding of how dynein, an exceptionally large motor protein that moves many intracellular cargos, works and is regulated. She developed one of the first systems to produce recombinant dynein and discovered that, unlike other cytoskeletal motors, dynein can take a wide variety of step sizes, forward and back and even sideways. She lives in San Diego, California.
Early life and education
Reck-Peterson was educated at Litchfield High School in Litchfield, Minnesota, where she served as senior class president and graduated as salutatorian in 1989. She was an all-state track and cross-country runner and team captain. She was inducted into the Litchfield High School Hall of Fame in 2017.
Career
Reck-Peterson became interested in molecular motors when she took the Physiology Course at the Marine Biological Laboratory at Woods Hole, Massachusetts. She chose the motor protein myosin as the topic of her Ph.D. work in the laboratories of Mark Mooseker and Peter Novick at Yale University. Her work focused on the class V myosins, which have multiple functions in the cell ranging from mRNA transport to cell polarity and membrane trafficking. She developed a modified in vitro motility assay to show that both Myo2p and Myo4p class V myosins in yeast appear to be non-processive motors in the absence of additional regulation, unlike their vertebrate counterparts.
In 2001, Reck-Peterson moved to UCSF to pursue post-doctoral studies with Ronald Vale. She began to work on dynein, a molecular motor that transports cargoes such as proteins, organelles and messenger RNAs to locations where they are needed in the cell. Dynein uses the energy stored in ATP to move towards the "mi
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https://en.wikipedia.org/wiki/Prevotella
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Prevotella is a genus of Gram-negative bacteria.
Prevotella spp. are members of the oral, vaginal, and gut microbiota and are often recovered from anaerobic infections of the respiratory tract. These infections include aspiration pneumonia, lung abscess, pulmonary empyema, and chronic otitis media and sinusitis. They have been isolated from abscesses and burns in the vicinity of the mouth, bites, paronychia, urinary tract infection, brain abscesses, osteomyelitis, and bacteremia associated with upper respiratory tract infections. Prevotella spp. predominate in periodontal disease and periodontal abscesses.
Role in gut microbiota
The human gut is mainly inhabited by two phyla of bacteria—Bacillota and Bacteroidota, the latter mostly dominated by Bacteroides and Prevotella genera. Prevotella and Bacteroides are thought to have had a common ancestor. Formally, the two genera were differentiated in 1990. However classification is ongoing. For example, Bacteroides melaninogenicus has been reclassified and split into Prevotella melaninogenica and Prevotella intermedia. Either Prevotella or Bacteroides dominate the gut and may be antagonistic. Prevotella is more common in non-Westernised populations consuming a plant-rich diet. In Western populations it has been associated with diets rich in fruits and vegetables. Genome analysis of Prevotella copri showed it was deficient in the ability to degrade host glycans and is more genetically equipped for plant glycan degradation. In a study of gut bacteria of children in Burkina Faso, Prevotella made up 53% of the gut bacteria but were absent in age-matched European children.
Long-term diet is reported to be associated with gut microbiome composition—those who eat protein and animal fats have predominantly Bacteroides bacteria, while those who consume more carbohydrates, especially fibre, feature Prevotella species.
Prevotella is associated with gut inflammation. Increased levels of P. copri might contribute to chronic infla
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https://en.wikipedia.org/wiki/DsbC%20protein%20family
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DsbC (Disulfide bond C) is a prokaryotic disulfide bond isomerase. The formation of native disulfide bonds play an important role in the proper folding of proteins and stabilize tertiary structures of the protein. DsbC is one of 6 proteins in the Dsb family in prokaryotes. The other proteins are DsbA, DsbB, DsbD, DsbE and DsbG. These enzymes work in tandem with each other to form disulfide bonds during the expression of proteins. DsbC and DsbG act as proofreaders of the disulfide bonds that are formed. They break non-native disulfide bonds that were formed and act as chaperones for the formation of native disulfide bonds. The isomerization of disulfide bonds occurs in the periplasm.
Enzyme Mechanism
DsbA, DsbC and DsbG have a common Cys-Xxx-Xxx-Cys (Cys-Cysteine) motif in their active site, where Xxx can be any amino acid. In the periplasm, DsbA oxidizes thiols in cysteines to form disulfide bonds in proteins. DsbA receives its oxidizing potential from the cytosol through DsbB. However, the probability of forming a non-native disulfide bond increases with the number of cysteines in the protein sequence. This leads to improperly folded proteins.
DsbC and DsbG facilitate the proper folding of the protein by breaking non-native disulfide bonds. In addition to this, DsbC also shows chaperone activity. The reduced cysteine on DsbC performs a nucleophilic attack on the target non-native disulfide bond, to form an unstable disulfide bond between DsbC and the protein. Another thiolate group in the protein then attacks this unstable bond. The final result would be the formation of a native disulfide bond and the reformation of the thiolate group in DsbC. DsbG also acts with a similar mechanism, but has a higher selectivity when compared with DsbC.
Both DsbC and DsbG receive their reducing power, through DsbD, from the cytosol. DsbC and DsbG have been maintained in their reduced forms to ensure proper folding of proteins, with the formation of multiple disulfide bonds.
E
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https://en.wikipedia.org/wiki/Atomic%20Ninjas
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Atomic Ninjas is a multiplayer 2.5D platform game developed by Czech company Grip Games. It was released for PlayStation 3 and PlayStation Vita. Grip Games planned to release Microsoft Windows and OS X versions; the game was greenlit on 27 November 2014, but is still unreleased as of 2018.
Gameplay
Players can choose if they want to play in split-screen or as an online game. The game also includes a single-player option. There are multiple modes such as deathmatch or capture the flag. Players can choose out of seven playable ninjas and seven arenas to play in.
Players can't kill each other in direct fight but have to push their enemy into a trap, which is part of an arena. There are also skills that you can upgrade
Characters
Sergei, the Ninja
A drunkard and an atomic engineer who loves to sleep while at work. He is responsible for a nuclear disaster which he miraculously survived and became an atomic ninja. He is looking for the last rehabilitation center to cure himself. Personal quote: "The shovel is mightier than the sword!"
Very Last Samurai
The position of the Last Samurai goes from father to son in his family. He has no successors. Personal quote: "Honor. Respect. Karaoke."
Masked Ninja
He hides his face because it is ugly. He killed his tutor who asked him if he is hiding his face to protect himself from fear in his soul or to scare his enemies. No personal quote.
Rogue Ninja
He never became a master even though he is great at combat and invisible as a ghost. He always failed in the tea ceremony. It fueled him with rage. He kills every ninja master he meets. Personal quote: "Would you like some tea?"
Old Monk
He is old, wise, compassionate and gentle but has problems with prostate and ungrateful grandchildren. Personal quote: "I had something important to tell you, but I forgot what it was!"
Psycho Ninja
The end of the world made him more resilient, tougher, stronger and willing to live. On the other hand, it made him a blood-lusting, giggling, der
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https://en.wikipedia.org/wiki/Complex%20segregation%20analysis
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Complex segregation analysis (CSA) is a technique within genetic epidemiology to determine whether there is evidence that a major gene underlies the distribution of a given phenotypic trait. CSA also provides evidence to whether the implicated trait is inherited in a Mendelian dominant, recessive, or codominant manner.
Purpose of CSA
CSA is often a preliminary step in genetic epidemiology. The purpose of CSA is to provide initial evidence that a single gene has a major effect on a particular phenotypic trait. Only phenotypic information, not genotypic information, is required for CSA. CSA can provide evidence, but not definitively prove a trait is under the control of a single gene. Evidence from CSA studies can be used to justify which phenotypes might be appropriate for more in-depth studies such as linkage analysis.
Study design and data analysis
CSA requires phenotypic information on family members in a pedigree. A variety of models with different parameters and assumptions about the nature of the inheritance of the trait are fit to the data. CSA studies may include non-genetic models which assume the trait has no genetic component and is only determined by environmental factors, models which include environmental components as well as multi-gene heritability components, and models which include environment, multi-gene heritability, and a single major gene to best fit the data. CSA software uses a maximum likelihood estimator to assign the best fitting coefficients to each component in all models. Nested models are then tested for their goodness of fit starting at the most complex. If two models are found to fit equally well, the more complex model is rejected in favor of the simpler model. If the best fitting model includes a single major gene component, there is evidence that the trait of interest is under Mendelian control.
Examples of publications using CSA
See also
Genetic epidemiology
Genetic segregation
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https://en.wikipedia.org/wiki/Link%20layer
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In computer networking, the link layer is the lowest layer in the Internet protocol suite, the networking architecture of the Internet. The link layer is the group of methods and communications protocols confined to the link that a host is physically connected to. The link is the physical and logical network component used to interconnect hosts or nodes in the network and a link protocol is a suite of methods and standards that operate only between adjacent network nodes of a network segment.
Despite the different semantics of layering between the Internet protocol suite and OSI model, the link layer is sometimes described as a combination of the OSI's data link layer (layer 2) and physical layer (layer 1).
The link layer is described in and . RFC 1122 considers local area network protocols such as Ethernet and other IEEE 802 networks (e.g. Wi-Fi), and framing protocols such as Point-to-Point Protocol (PPP) to belong to the link layer.
Definition in standards and textbooks
Local area networking standards such as Ethernet and IEEE 802.3 specifications use terminology from the seven-layer OSI model rather than the TCP/IP model. The TCP/IP model, in general, does not consider physical specifications, rather it assumes a working network infrastructure that can deliver media-level frames on the link. Therefore, RFC 1122 and RFC 1123, the definition of the TCP/IP model, do not discuss hardware issues and physical data transmission and set no standards for those aspects. Some textbook authors have supported the interpretation that physical data transmission aspects are part of the link layer. Others assumed that physical data transmission standards are not considered communication protocols, and are not part of the TCP/IP model. These authors assume a hardware layer or physical layer below the link layer, and several of them adopt the OSI term data link layer instead of link layer in a modified description of layering. In the predecessor to the TCP/IP model, the ARPAn
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https://en.wikipedia.org/wiki/Budapest%20Reference%20Connectome
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The Budapest Reference Connectome server computes the frequently appearing anatomical brain connections of 418 healthy subjects. It has been prepared from diffusion MRI datasets of the Human Connectome Project into a reference connectome (or brain graph), which can be downloaded in CSV and GraphML formats and visualized on the site in 3D.
Features
The Budapest Reference Connectome has 1015 nodes, corresponding to anatomically identified gray matter areas. The user can set numerous parameters and the resulting consensus connectome is readily visualized on the webpage. Users can zoom, rotate, and query the anatomical label of the nodes on the graphical component.
Background
Budapest Reference Connectome is a consensus graph of the brain graphs of 96 subjects in Version 2 and 418 subjects in Version 3. Only those edges are returned which are present in a given percentage of the subjects. Each of the selected edges has a certain weight in each of the graphs containing that edge, so these multiple weights are combined into a single weight, by taking either their mean (i.e., average) or median. The user interface allows the customization of these parameters: the user can select the minimum frequency of the edges returned. There is an option for viewing and comparing the female or male reference connectomes. The connectomes of women contain significantly more edges than those of men, and a larger portion of the edges in the connectomes of women run between the two hemispheres.
Discoveries
The Budapest Reference Connectome has led the researchers to the discovery of the Consensus Connectome Dynamics of the human brain graphs. The edges appeared in all of the brain graphs form a connected subgraph around the brainstem. By allowing gradually less frequent edges, this core subgraph grows continuously, as a shrub. The growth dynamics may reflect the individual brain development and provide an opportunity to direct some edges of the human consensus brain graph.
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https://en.wikipedia.org/wiki/Vertical%20Distribution%20of%20Ice%20in%20Arctic%20Clouds
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Vertical Distribution of Ice in Arctic Clouds (VERDI) is the name of a German research project on the topic of Arctic clouds. Measurements within this project were conducted in April and May 2012 around Inuvik, Canada, organized by the University of Leipzig. The project aims at an improvement of knowledge about the effects of clouds in the Arctic climate system. The main question within VERDI is the distribution of ice crystals and liquid water droplets within the clouds. That distribution depends on various parameters, such as temperature and the cloud's life cycle.
Measurements
During VERDI, airborne observations were conducted inside and above low-level Arctic clouds. Their properties were characterized in detail. The observation methods included remote sensing (both active and passive) covering a large cloud extent, as well as in-situ probing of cloud droplets and ice crystals. The measurements were conducted on board of the research aircraft Polar 5 (call sign C-GAWI) of the Alfred Wegener Institute for Polar and Marine Research, which was based in Inuvik, Canada, for the measurements. The measurement flights were located in the south-eastern Beaufort Sea north of the Mackenzie Delta in the Northwest Territories. Altogether, sixteen flights were conducted between 21 April and 17 May 2012.
Funding
VERDI has been funded by the Alfred Wegener Institute for Polar and Marine Research, by the German Research Foundation (DFG), by Forschungszentrum Jülich (FZJ), and by the Karlsruhe Institute of Technology (KIT). In addition, the Max Planck Institute for Chemistry in Mainz, the Johannes Gutenberg University of Mainz and the Institute of Atmospheric Physics of the German Aerospace Center. Logistically, the campaign was supported by the Aurora Research Institute in Inuvik.
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https://en.wikipedia.org/wiki/Queen%27s%20graph
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In mathematics, a queen's graph is an undirected graph that represents all legal moves of the queen—a chess piece—on a chessboard. In the graph, each vertex represents a square on a chessboard, and each edge is a legal move the queen can make, that is, a horizontal, vertical or diagonal move by any number of squares. If the chessboard has dimensions , then the induced graph is called the queen's graph.
Independent sets of the graphs correspond to placements of multiple queens where no two queens are attacking each other. They are studied in the eight queens puzzle, where eight non-attacking queens are placed on a standard chessboard. Dominating sets represent arrangements of queens where every square is attacked or occupied by a queen; five queens, but no fewer, can dominate the chessboard.
Colourings of the graphs represent ways to colour each square so that a queen cannot move between any two squares of the same colour; at least n colours are needed for an chessboard, but 9 colours are needed for the board.
Properties
There is a Hamiltonian cycle for each queen's graph, and the graphs are biconnected (they remain connected if any single vertex is removed). The special cases of the and queen's graphs are complete.
Independence
An independent set of the graph corresponds to a placement of several queens on a chessboard such that no two queens are attacking each other. In an chessboard, the largest independent set contains at most n vertices, as no two queens can be in the same row or column. This upper bound can be achieved for all n except n=2 and n=3. In the case of n=8, this is the traditional eight queens puzzle.
Domination
A dominating set of the queen's graph corresponds to a placement of queens such that every square on the chessboard is either attacked or occupied by a queen. On an chessboard, five queens can dominate, and this is the minimum number possible (four queens leave at least two squares unattacked). There are 4,860 such placements
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https://en.wikipedia.org/wiki/List%20of%20causes%20of%20death%20by%20rate
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The following is a list of the causes of human deaths worldwide for different years arranged by their associated mortality rates. In 2002, there were about 57 million deaths. In 2005, according to the World Health Organization (WHO) using the International Classification of Diseases (ICD), about 58 million people died. In 2010, according to the Institute for Health Metrics and Evaluation, 52.8 million people died. In 2016, the WHO recorded 56.7 million deaths with the leading cause of death as cardiovascular disease causing more than 17 million deaths (about 31% of the total) as shown in the chart to the side.
Some causes listed include deaths also included in more specific subordinate causes, and some causes are omitted, so the percentages may only sum approximately to 100%. The causes listed are relatively immediate medical causes, but the ultimate cause of death might be described differently. For example, tobacco smoking often causes lung disease or cancer, and alcohol use disorder can cause liver failure or a motor vehicle accident. For statistics on preventable ultimate causes, see preventable causes of death.
Besides frequency, other measures to compare, consider and monitor trends of causes of deaths include disability-adjusted life year (DALY) and years of potential life lost (YPLL).
By frequency
Age standardized death rate, per 100,000, by cause, in 2017, and percentage change 2007–2017.
Overview table
This first table gives a convenient overview of the general categories and broad causes. The leading cause is cardiovascular disease at 31.59% of all deaths.
Developed vs. developing economies
Top causes of death, according to the World Health Organization report for the calendar year 2001:
Detailed table
This table gives a more detailed and specific breakdown of the causes for the year 2017:
By lost years
Underlying causes
Causes of death can be structured into immediate causes of death or primary causes of death, conditions leading to cause of
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https://en.wikipedia.org/wiki/Nicolas%20Fizes
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Nicolas Fizes (27 October 1648 in Frontignan – 1718) was a French professor of mathematics and hydrography, who lived under the reign of Louis XIV. He is especially known as the librettist who wrote L'Opéra de Frontignan (1670), a play in Occitan, dealing with a slight love intrigue, and an idyllic poem on the fountain of Frontignan.
Career
Nicolas Fizes's parents were carpenters in the French Navy. He studied with the Jesuits, and became engineer to armies and a doctor of law. In 1682 he held the first professorship of mathematics and hydrography in Montpellier.
From 1689, he headed a school of hydrography in Frontignan. In the hall of the Town Hall, he taught a few young sailors the concepts of mathematics and astrology. But this school was previously free, and Fizes asked for a salary of 150 pounds a year, which led to a conflict with the consuls of Frontignan. The school only survived 7 years, and closed its doors in 1696.
Bibliography
Lucien Albagnac, Contribution à l'Histoire de Frontignan (no ISBN)
André Cablat, René Michel, Maurice Nougaret, Jean Valette, La Petite Encyclopédie de Frontignan la Peyrade (no ISBN)
See also
Occitan literature
1648 births
People from Hérault
1718 deaths
French mathematicians
Mathematics educators
French hydrographers
French opera librettists
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https://en.wikipedia.org/wiki/SMPTE%20372M
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SMPTE 372M is a standard published by SMPTE which expands upon SMPTE 259M, SMPTE 344M, and SMPTE 292M allowing for bit-rates of 2.970 Gbit/s, and 2.970/1.001 Gbit/s over two wires. These bit-rates are sufficient for 1080p video at 50 or 60 frames per second.
This standard is informally known as dual-link HD-SDI and is part of a family of standards that define a Serial Digital Interface.
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https://en.wikipedia.org/wiki/Linear%20canonical%20transformation
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In Hamiltonian mechanics, the linear canonical transformation (LCT) is a family of integral transforms that generalizes many classical transforms. It has 4 parameters and 1 constraint, so it is a 3-dimensional family, and can be visualized as the action of the special linear group SL2(R) on the time–frequency plane (domain). As this defines the original function up to a sign, this translates into an action of its double cover on the original function space.
The LCT generalizes the Fourier, fractional Fourier, Laplace, Gauss–Weierstrass, Bargmann and the Fresnel transforms as particular cases. The name "linear canonical transformation" is from canonical transformation, a map that preserves the symplectic structure, as SL2(R) can also be interpreted as the symplectic group Sp2, and thus LCTs are the linear maps of the time–frequency domain which preserve the symplectic form, and their action on the Hilbert space is given by the Metaplectic group.
The basic properties of the transformations mentioned above, such as scaling, shift, coordinate multiplication are considered. Any linear canonical transformation is related to affine transformations in phase space, defined by time-frequency or position-momentum coordinates.
Definition
The LCT can be represented in several ways; most easily, it can be parameterized by a 2×2 matrix with determinant 1, i.e., an element of the special linear group SL2(C). Then for any such matrix with ad − bc = 1, the corresponding integral transform from a function to is defined as
Special cases
Many classical transforms are special cases of the linear canonical transform:
Scaling
Scaling, , corresponds to scaling the time and frequency dimensions inversely (as time goes faster, frequencies are higher and the time dimension shrinks):
Fourier transform
The Fourier transform corresponds to a clockwise rotation by 90° in the time–frequency plane, represented by the matrix
Fractional Fourier transform
The fractional Fourier transform
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https://en.wikipedia.org/wiki/Nebraska%20statistical%20areas
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The U.S. currently has 15 statistical areas that have been delineated by the Office of Management and Budget (OMB). On March 6, 2020, the OMB delineated two combined statistical areas, four metropolitan statistical areas, and nine micropolitan statistical areas in Nebraska.
Statistical areas
The Office of Management and Budget (OMB) has designated more than 1,000 statistical areas for the United States and Puerto Rico. These statistical areas are important geographic delineations of population clusters used by the OMB, the United States Census Bureau, planning organizations, and federal, state, and local government entities.
The OMB defines a core-based statistical area (commonly referred to as a CBSA) as "a statistical geographic entity consisting of the county or counties (or county-equivalents) associated with at least one core of at least 10,000 population, plus adjacent counties having a high degree of social and economic integration with the core as measured through commuting ties with the counties containing the core." The OMB further divides core-based statistical areas into metropolitan statistical areas (MSAs) that have "a population of at least 50,000" and micropolitan statistical areas (μSAs) that have "a population of at least 10,000, but less than 50,000."
The OMB defines a combined statistical area (CSA) as "a geographic entity consisting of two or more adjacent core-based statistical areas with employment interchange measures of at least 15%." The primary statistical areas (PSAs) include all combined statistical areas and any core-based statistical area that is not a constituent of a combined statistical area.
Table
The table below describes the 15 United States statistical areas and 93 counties of the State of Nebraska with the following information:
The combined statistical area (CSA) as designated by the OMB.
The CSA population according to 2019 US Census Bureau population estimates.
The core based statistical area (CBSA) as designated by th
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https://en.wikipedia.org/wiki/OnStream
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OnStream Holdings of the Netherlands was spun off from Philips in 1998 and went bankrupt for a second time in 2003.
As a result of its first bankruptcy in 2001, the company was split into two parts, OnStream Data and OnStream MST. The "Data" division manufactured magnetic tape products and the "MST" division produced the thin film tape heads. MST also produced microsieves and microelectromechanical systems products. After the second OnStream bankruptcy in 2003, the MST division was reborn as fluXXion, a maker of high-tech filtering products. fluXXion had some success in filtering beer and other food products but went bankrupt in 2011.
Prior to the first bankruptcy, the CEO was William B. Beierwaltes, a tape systems pioneer and founder of Colorado Memory Systems.
The company's magnetic tape data storage technology was called Advanced Digital Recording (ADR). Tape drives based on this technology were relatively high in data capacity and low in price.
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https://en.wikipedia.org/wiki/Superior%20lateral%20cutaneous%20nerve%20of%20arm
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The superior lateral cutaneous nerve of arm (or superior lateral brachial cutaneous nerve) is the continuation of the posterior branch of the axillary nerve, after it pierces the deep fascia. It contains axons from C5-C6 ventral rami.
Structure
It sweeps around the posterior border of the deltoideus and supplies the skin over the lower two-thirds of the posterior part of this muscle, as well as that covering the long head of the triceps brachii.
See also
Posterior cutaneous nerve of arm (Posterior brachial)
Medial cutaneous nerve of arm (Medial brachial)
Lateral cutaneous nerve of forearm (Lateral antebrachial)
Additional images
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https://en.wikipedia.org/wiki/Meat%20emulsion
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Meat emulsion is a two-phase system, with the dispersed phase consisting of either solid or liquid fat particles and the continuous phase being the water containing salts and dissolved, gelled and suspended proteins. Thus, they can be classified as oil-in-water emulsion. Meat emulsion is not a true emulsion since the two phases involved are not liquids and the fat droplets in a commercial emulsion are larger than 50 μm in diameter and thus do not conform to one of the requirement of a classical emulsion. Common examples of meat emulsions include bologna, frankfurters, sausages, and meatloaf.
The continuous phase mainly consists of water, water-soluble proteins and salt-soluble proteins. The dispersed phase or discontinuous phase consists of fat droplets.
The water-soluble proteins are sarcoplasmic proteins such as myoglobin and other pigments; salt-soluble proteins are myofibrillar proteins such as myosin, actin, and actinins.
Meat emulsifiers
When used in food products, iota carrageenan and sodium stearoyl lactylate have a synergistic effect allowing for stabilizing/emulsifying that is not obtained with any other type of carrageenan (kappa/lambda) or with other emulsifiers (monoglycerides, etc.). Sodium stearoyl lactylate combined with iota carrageenan is capable of producing emulsions under both hot and cold conditions using either vegetable or animal fat.
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https://en.wikipedia.org/wiki/Hosoya%20index
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The Hosoya index, also known as the Z index, of a graph is the total number of matchings in it. The Hosoya index is always at least one, because the empty set of edges is counted as a matching for this purpose. Equivalently, the Hosoya index is the number of non-empty matchings plus one. The index is named after Haruo Hosoya. It is used as a topological index in chemical graph theory.
Complete graphs have the largest Hosoya index for any given number of vertices; their Hosoya indices are the telephone numbers.
History
This graph invariant was introduced by Haruo Hosoya in 1971. It is often used in chemoinformatics for investigations of organic compounds.
In his article, "The Topological Index Z Before and After 1971," on the history of the notion and the associated inside stories, Hosoya writes that he introduced the Z index to report a good correlation of the boiling points of alkane isomers and their Z indices, basing on his unpublished 1957 work carried out while he was an undergraduate student at the University of Tokyo.
Example
A linear alkane, for the purposes of the Hosoya index, may be represented as a path graph without any branching. A path with one vertex and no edges (corresponding to the methane molecule) has one (empty) matching, so its Hosoya index is one; a path with one edge (ethane) has two matchings (one with zero edges and one with one edges), so its Hosoya index is two. Propane (a length-two path) has three matchings: either of its edges, or the empty matching. n-butane (a length-three path) has five matchings, distinguishing it from isobutane which has four. More generally, a matching in a path with edges either forms a matching in the first edges, or it forms a matching in the first edges together with the final edge of the path. This case analysis shows that the Hosoya indices of linear alkanes obey the recurrence governing the Fibonacci numbers, and because they also have the same base case they must equal the Fibonacci numbers. The s
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https://en.wikipedia.org/wiki/Live%20migration
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Live migration, also called migration, refers to the process of moving a running virtual machine (VM) or application between different physical machines without disconnecting the client or application. Memory, storage, and network connectivity of the virtual machine are transferred from the original guest machine to the destination. The time between stopping the VM or application on the source and resuming it on destination is called 'downtime'. When the downtime of a VM during live migration is small enough that it is not noticeable by the end user, it is called a 'seamless' live migration.
Live migration of Virtual Machines
Two techniques for moving the virtual machine's memory state from the source to the destination are pre-copy memory migration and post-copy memory migration.
Pre-copy memory migration
Pre-copy phase
In pre-copy phase, the Hypervisor copies all the memory pages from source to destination while the VM is still running on the source. If some memory pages change (become 'dirty') during the pre-copy phase, they will be copied again and again over several 'pre-copy rounds'. Usually the pre-copy phase ends when the number of dirtied pages remaining becomes small enough to yield a short stop-and-copy phase. However, if a VM keeps dirtying memory faster than can be re-copied to the destination, then pre-copy phase will end after a set time limit or maximum number of pre-copy rounds to begin the next stop-and-copy phase.
Stop-and-copy phase
After the pre-copy phase, the VM will be paused on the source host, the remaining dirty pages will be copied to the destination, and the VM will be resumed at the destination. The downtime due to this phase can range from a few milliseconds to seconds depending on the number of dirty pages transferred during downtime. VMs that dirty a lot of memory during the pre-copy phase tend to have a larger downtime.
Post-copy memory migration
Post-copy VM migration is initiated by suspending the VM at the source. With th
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https://en.wikipedia.org/wiki/Wang%202200
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The Wang 2200 was an all-in-one minicomputer released by Wang Laboratories in May 1973. Unlike some other desktop computers, such as the HP 9830, it had a cathode-ray tube (CRT) in a cabinet that also included an integrated computer-controlled cassette tape storage unit and keyboard. It was microcoded to run BASIC on startup, making it similar to home computers of a few years later. About 65,000 systems were shipped in its lifetime and it found wide use in small and medium-size businesses worldwide.
The 2200 series evolved from a singular desktop computer into larger systems able to support up to 16 workstations which utilized commercial disk technologies that appeared in the late 1970s and early 1980s. The disk subsystems could be attached to up to 15 computers giving a theoretical upper limit of 240 workstations in a single cluster.
Unlike other Wang product lines such as the VS and OIS, value-added resellers (VARs) were used to customize and market 2200 systems to customers. One such solution deployed dozens of 2200 systems and was developed in conjunction with Hawaii- and Hong Kong-based firm, Algorithms, Inc. It provided paging (beeper) services for much of the Hong Kong market in the early 1980s.
History
Early 2200 models
The first models of the 2200, released in April 1973, were the 2200A and B. This differed in the amount of microcode, with the B model holding additional commands in Wang BASIC. The extra commands in the B model were mostly related to data handling, allowing BASIC programs to construct databases with relative ease. The later C model added a small number of additional commands, including simple error handling.
The A, B and C were replaced by the S and T models, which re-implemented the CPU using newer, higher-density large-scale integration parts. S models added commands to convert strings to and from numbers and a few other commands. The T version added a complete set of matrix math commands like those seen in later versions of Dartmouth
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https://en.wikipedia.org/wiki/Flavelle%20Medal
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The Flavelle Medal is an award of the Royal Society of Canada "for an outstanding contribution to biological science during the preceding ten years or for significant additions to a previous outstanding contribution to biological science". It is named in honour of Joseph Wesley Flavelle and is awarded bi-annually. The award consists of a gold plated silver medal.
Recipients
Source: Royal Society of Canada
2022 - Graham Bell, FRSC
2020 - Marla Sokolowski, FRSC
2018 - Frank Plummer, FRSC
2016 -
2014 - Spencer Barrett, FRSC
2012 - Siegfried Hekimi, FRSC
2010 - Kenneth B. Storey, FRSC
2008 - John Smol, FRSC
2006 - Brett Finlay, FRSC
2004 - Brian D. Sykes, FRSC
2002 - Lewis E. Kay
2000 - David R. Jones, FRSC
1998 - Anthony Pawson, FRSC
1996 - Ian C. P. Smith, FRSC
1994 - Robert J. Cedergren, MSRC
1992 - Michael Smith, FRSC
1990 - Peter W. Hochachka, FRSC
1988 - Robert Haynes, FRSC
1986 - Neil Towers, FRSC
1984 - Robert G.E. Murray, FRSC
1982 - Clayton Oscar Person, FRSC
1980 - Gordon Dixon, FRSC
1978 - Louis Siminovitch, FRSC
1976 - Michael Shaw, FRSC
1974 - Juda Hirsh Quastel, FRSC
1972 - Douglas Harold Copp, FRSC
1970 - William Edwin Ricker, FRSC
1968 - Jacques Genest, MSRC
1966 - Erich Baer, FRSC
1965 - William Stewart Hoar, FRSC
1964 - Gleb Krotkov, FRSC
1963 - Robert James Rossiter, FRSC
1962 - Frederick Ernest Joseph Fry, FRSC
1961 - Charles Philippe Leblond, FRSC
1960 - Edmund Murton Walker, FRSC
1959 - Murray L. Barr, FRSC
1958 - Allan Grant Lochhead, FRSC
1957 - Thomas Wright M. Cameron, FRSC
1956 - George Lyman Duff, FRSC
1955 - Charles Samuel Hanes, FRSC
1954 - David Alymer Scott, FRSC
1953 - Everitt George Dunne Murray, FRSC
1952 - Archibald G. Huntsman, FRSC
1951 - Wilder Penfield, FRSC
1950 - Charles Best, FRSC
1949 - W. P. Thompson, FRSC
1948 - Margaret Newton, FRSC
1947 - Guilford Bevil Reed, FRSC
1946 - William Rowan, FRSC
1945 - Robert Boyd Thomson, FRSC
1944 - Velyien Ewart Henderson, FRSC
1943 - B.
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https://en.wikipedia.org/wiki/Scour%20Inc.
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Scour Inc. was a multimedia Internet search engine, and provided Scour Exchange, an early peer-to-peer file exchange service.
History
Scour was founded by five students (Vince Busam, Michael Todd, Dan Rodrigues, Jason Droege and Kevin Smilak) from the Computer Science Department of the University of California, Los Angeles (UCLA) in December 1997. By mid-1998 Ilya Haykinson and Travis Kalanick, also Computer Science students at UCLA joined the founding team. It moved into the spotlight a year later when in June 1998, Scour received its first investment from former Disney president Michael Ovitz and Ron Burkle of Yucaipa companies.
The company's early products were an SMB search engine and Scour Media Agent, a Windows application to download files from SMB shares. The search engine would probe IP addresses for publicly shared files and then index them for download by other users.
In 1998, the company developed a web search engine as well, crawling the World Wide Web for links to multimedia audio, video and images.
In 1999 Scour received an investment from Michael Ovitz and the Yucaipa Company, an investment arm of the billionaire Ronald Burkle. Together, the total investment represented a controlling share in the company. After the investment, Scour expanded in terms of product offerings and personnel. The company launched a software product named MyCaster which allowed users to stream audio over the network, optionally mixing microphone input with an MP3 audio file in real time.
Faced with the increasing popularity of Napster, Scour developed a competing peer-to-peer service named Scour Exchange. Unlike Napster, the Scour software supported video and images in addition to just audio files, and integrated all users into one network. The company also tied its web site promotional materials to the Scour Exchange software and attempted to leverage its web and SMB indexes in providing additional search results inside the Scour Exchange application.
In the summer of
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https://en.wikipedia.org/wiki/Density%20matrix%20renormalization%20group
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The density matrix renormalization group (DMRG) is a numerical variational technique devised to obtain the low-energy physics of quantum many-body systems with high accuracy. As a variational method, DMRG is an efficient algorithm that attempts to find the lowest-energy matrix product state wavefunction of a Hamiltonian. It was invented in 1992 by Steven R. White and it is nowadays the most efficient method for 1-dimensional systems.
History
The first application of the DMRG, by Steven R. White and Reinhard Noack, was a toy model: to find the spectrum of a spin 0 particle in a 1D box. This model had been proposed by Kenneth G. Wilson as a test for any new renormalization group method, because they all happened to fail with this simple problem. The DMRG overcame the problems of previous renormalization group methods by connecting two blocks with the two sites in the middle rather than just adding a single site to a block at each step as well as by using the density matrix to identify the most important states to be kept at the end of each step. After succeeding with the toy model, the DMRG method was tried with success on the quantum Heisenberg model.
Principle
The main problem of quantum many-body physics is the fact that the Hilbert space grows exponentially with size. In other words if one considers a lattice, with some Hilbert space of dimension on each site of the lattice, then the total Hilbert space would have dimension , where is the number of sites on the lattice. For example, a spin-1/2 chain of length L has 2L degrees of freedom. The DMRG is an iterative, variational method that reduces effective degrees of freedom to those most important for a target state. The state one is most often interested in is the ground state.
After a warmup cycle, the method splits the system into two subsystems, or blocks, which need not have equal sizes, and two sites in between. A set of representative states has been chosen for the block during the warmup. This set of
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https://en.wikipedia.org/wiki/United%20States%20Marine%20Mammal%20Program
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The United States Marine Mammal Program is an organization developed by the United States National Committee and the International Marine Mammal Working Group of the International Biological Program in 1969, for the study of marine mammals.
The United States Marine Mammal program was directed by an eleven member called the Marine Mammal Council (MMC) that was appointed by the United States Marine Mammal Working Group. Daily operations was overseen by a four member Executive committee that was named by the MMC.
Some notable things the MMC did include aiding in the development of a Marine Mammal Study Center at the Smithsonian, publishing the Marine Mammal Newsletter, sponsoring marine mammal conferences, and coordinating existing and new research through its research program.
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https://en.wikipedia.org/wiki/GEOS-3
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GEOS-3, or Geodynamics Experimental Ocean Satellite 3, or GEOS-C, was the third and final satellite as part of NASA's Geodetic Earth Orbiting Satellite/Geodynamics Experimental Ocean Satellite program (NGSP) to better understand and test satellite tracking systems. For GEOS 1 and GEOS 2, the acronym stands for Geodetic Earth Orbiting Satellite; this was changed for GEOS-3.
Introduction
The satellite mission was designed to further an understanding of the earth's gravitational field, size and shape of the terrestrial geoid, deep ocean tides, sea state, current structure, crustal structure, solid earth dynamics, and remote sensing technology. Jerome Rosenburg at NASA Headquarters initiated the GEOS-3 project in 1970. The project was to serve as a stepping stone between the GEOS program and the emerging NASA Earth and Ocean Physics Application Program. GEOS-1 and GEOS-2 had provided useful information about the structure of the earth's gravitational field, but new technology was deemed necessary to gain a further understanding. The project was cancelled due to budgetary concerns after an initial 1-year study, but was re-instated in late 1971. The satellite was launched on April 9, 1975 and remained operational until late July 1979.
Instruments
The following is a list of instruments/systems that were on board or part of the GEOS-3 satellite, including a description of their general purpose:
Radar Altimeter (ALT) – A multimode radar system with the ability to provide precise satellite-to-ocean surface height measurements. The radar system provided global and intensive data gathering modes, which could provide height precision measurements at 50 cm and 20 cm respectively.
Retroreflector Array (RRA) – An array of retroreflectors. These allow a ground-based laser to provide range information.
Doppler System – A system of dual frequency space borne doppler beacons at 162 and 324 MHz and a ground-based receiver station. This system was used to measure the effects
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https://en.wikipedia.org/wiki/Exportation%20%28logic%29
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Exportation is a valid rule of replacement in propositional logic. The rule allows conditional statements having conjunctive antecedents to be replaced by statements having conditional consequents and vice versa in logical proofs. It is the rule that:
Where "" is a metalogical symbol representing "can be replaced in a proof with." In strict terminology, is the law of exportation, for it "exports" a proposition from the antecedent of to its consequent. Its converse, the law of importation, , "imports" a proposition from the consequent of to its antecedent.
Formal notation
The exportation rule may be written in sequent notation:
where is a metalogical symbol meaning that is a syntactic equivalent of in some logical system;
or in rule form:
,
where the rule is that wherever an instance of "" appears on a line of a proof, it can be replaced with "" and vice versa;
or as the statement of a truth-functional tautology or theorem of propositional logic:
where , , and are propositions expressed in some logical system.
Natural language
Truth values
At any time, if P→Q is true, it can be replaced by P→(P∧Q).
One possible case for P→Q is for P to be true and Q to be true; thus P∧Q is also true, and P→(P∧Q) is true.
Another possible case sets P as false and Q as true. Thus, P∧Q is false and P→(P∧Q) is false; false→false is true.
The last case occurs when both P and Q are false. Thus, P∧Q is false and P→(P∧Q) is true.
Example
It rains and the sun shines implies that there is a rainbow.
Thus, if it rains, then the sun shines implies that there is a rainbow.
If my car is on, when I switch the gear to D the car starts going.
If my car is on and I have switched the gear to D, then the car must start going.
Proof
The following proof uses material implication, double negation, De Morgan's laws, the negation of the conditional statement, the associative property of conjunction, the negation of another conditional statement, and double negation again, in tha
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https://en.wikipedia.org/wiki/Aerated%20Bread%20Company
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The Aerated Bread Company Ltd (A.B.C.) was a British company founded and headquartered in London. Although it is often remembered as running a large chain of tea rooms in Britain and other parts of the world, it was originally established in 1862 by John Dauglish as a bakery using a revolutionary new method he had developed, with the tea rooms starting in 1864.
History
Founding
The Aerated Bread Company Ltd was founded in 1862 by John Dauglish (1824–1866). The business was created as an incorporated company listed on the London Stock Exchange (LSE). When the company was floated, its failure was predicted and its initial public offering was poorly supported. However, its initial £1 shares had risen to £5 7s 8d by 1890. By 1898, shares had more than doubled from their 1890 value and were trading at £12 per share and declaring a dividend of percent. By 1899, A.B.C. shares had increased a further percent and were trading at £14 per share.
Technology
Dauglish earned his medical degree at Edinburgh. Having been thoroughly unimpressed by the Scottish bread of the day, he began to make his own, and to study the science associated with the process. When he applied his earlier studies in chemistry to the process of bread making, he determined that it would be possible to produce carbonic acid gas in bread without yeast. He established that if one could instead introduce carbon dioxide to the process—by dissolving it into solution in the water—this would eliminate the need for fermentation, dramatically reduce the need for physical contact with the dough on the part of the workers, and consequently introduce a greater level of cleanliness into the bread-making process. Dauglish sought to abolish manual kneading, which he believed was unclean and unhealthy. Some years later, an 1878 issue of the scientific journal Nature reported:
As to the perfect cleanliness of this mechanical process for making bread there can be no question; it is immeasurably superior to the barbarou
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https://en.wikipedia.org/wiki/Agaricus%20abruptibulbus
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Agaricus abruptibulbus is a species of mushroom in the genus Agaricus. It is commonly known as the abruptly-bulbous agaricus or the flat-bulb mushroom. First described by the mycologist Charles Horton Peck, this bulbous-stemmed edible species smells slightly of anise or bitter almond, and turns yellow when bruised or cut. The mushroom is medium-sized, with a white, yellow-staining cap on a slender stipe that has a wide, flat bulb on the base.
Taxonomy and classification
The species was originally named Agaricus abruptus by American mycologist Charles Horton Peck in 1900. In his 1904 publication Report of the State Botanist, he changed the name to Agaricus abruptibulbus. He explained that Elias Magnus Fries had earlier named a species in the subgenus Flammula, which he called Agaricus abruptus; the subgenus was later raised to the rank of genus, and the species was given the name Flammula abruptus. Under the transitioning nomenclatural conventions of the time, it was unclear if Agaricus abruptus would remain available for use, so Peck changed the name.
Agaricus abruptibulbus belongs to Agaricus section Arvenses, a clade within the genus Agaricus. Along with A. abruptibulbus, section Arvenses contains the species A. silvicola, A. arvensis, and formerly also A. semotus.
Some American authors consider this species to be synonymous with A. silvicola, while some in Europe have synonymized it with the similar species A. essettei. American mycologists Steve Trudell and Joseph Ammirati noted in a 2009 field guide: "The name A. abruptibulbus has been applied to forms with bulbous stipe bases, but variation in stipe shape is so great that the use of this name has been largely abandoned."
Description
The cap is whitish in color and convex in shape, reaching up to in diameter, sometimes with an umbo. After being scratched, cut, or bruised, the cap turns yellow. The stipe is long by thick and bulbous at the base. A large, white annular ring is present on the stipe. The gi
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