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https://en.wikipedia.org/wiki/Exponential%20factorial
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The exponential factorial is a positive integer n raised to the power of n − 1, which in turn is raised to the power of n − 2, and so on in a right-grouping manner. That is,
The exponential factorial can also be defined with the recurrence relation
The first few exponential factorials are 1, 2, 9, 262144, ... ( or ). For example, 262144 is an exponential factorial since
Using the recurrence relation, the first exponential factorials are:
1
21 = 2
32 = 9
49 = 262144
5262144 = 6206069878...8212890625 (183231 digits)
The exponential factorials grow much more quickly than regular factorials or even hyperfactorials. The number of digits in the exponential factorial of 6 is approximately 5 × 10183 230.
The sum of the reciprocals of the exponential factorials from 1 onwards is the following transcendental number:
This sum is transcendental because it is a Liouville number.
Like tetration, there is currently no accepted method of extension of the exponential factorial function to real and complex values of its argument, unlike the factorial function, for which such an extension is provided by the gamma function. But it is possible to expand it if it is defined in a strip width of 1.
Similarly, there is disagreement about the appropriate value at 0; any value would be consistent with the recursive definition. A smooth extension to the reals would satisfy , which suggests a value strictly between 0 and 1.
Related functions, notation and conventions
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https://en.wikipedia.org/wiki/Motor%20coordination
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In physiology, motor coordination is the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. This coordination is achieved by adjusting kinematic and kinetic parameters associated with each body part involved in the intended movement. The modifications of these parameters typically relies on sensory feedback from one or more sensory modalities (see multisensory integration), such as proprioception and vision.
Properties
Large Degrees of Freedom
Goal-directed and coordinated movement of body parts is inherently variable because there are many ways of coordinating body parts to achieve the intended movement goal. This is because the degrees of freedom (DOF) is large for most movements due to the many associated neuro-musculoskeletal elements. Some examples of non-repeatable movements are when pointing or standing up from sitting. Actions and movements can be executed in multiple ways because synergies (as described below) can vary without changing the outcome. Early work from Nikolai Bernstein worked to understand how coordination was developed in executing a skilled movement. In this work, he remarked that there was no one-to-one relationship between the desired movement and coordination patterns to execute that movement. This equivalence suggests that any desired action does not have a particular coordination of neurons, muscles, and kinematics.
Complexity
The complexity of motor coordination goes unnoticed in everyday tasks, such as in the task of picking up and pouring a bottle of water into a glass. This seemingly simple task is actually composed of multiple complex tasks. For instance, this task requires the following:
(1) properly reaching for the water bottle and then configuring the hand in a way that enables grasping the bottle.
(2) applying the correct amount of grip force to grasp the bottle without crushing it.
(3) coordinating the muscles required for lifting and articulating the bottle so that
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https://en.wikipedia.org/wiki/Geometric%20graph%20theory
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Geometric graph theory in the broader sense is a large and amorphous subfield of graph theory, concerned with graphs defined by geometric means. In a stricter sense, geometric graph theory studies combinatorial and geometric properties of geometric graphs, meaning graphs drawn in the Euclidean plane with possibly intersecting straight-line edges, and topological graphs, where the edges are allowed to be arbitrary continuous curves connecting the vertices; thus, it can be described as "the theory of geometric and topological graphs" (Pach 2013). Geometric graphs are also known as spatial networks.
Different types of geometric graphs
A planar straight-line graph is a graph in which the vertices are embedded as points in the Euclidean plane, and the edges are embedded as non-crossing line segments. Fáry's theorem states that any planar graph may be represented as a planar straight line graph. A triangulation is a planar straight line graph to which no more edges may be added, so called because every face is necessarily a triangle; a special case of this is the Delaunay triangulation, a graph defined from a set of points in the plane by connecting two points with an edge whenever there exists a circle containing only those two points.
The 1-skeleton of a polyhedron or polytope is the set of vertices and edges of said polyhedron or polytope. The skeleton of any convex polyhedron is a planar graph, and the skeleton of any k-dimensional convex polytope is a k-connected graph. Conversely, Steinitz's theorem states that any 3-connected planar graph is the skeleton of a convex polyhedron; for this reason, this class of graphs is also known as the polyhedral graphs.
A Euclidean graph is a graph in which the vertices represent points in the plane, and each edge is assigned the length equal to the Euclidean distance between its endpoints. The Euclidean minimum spanning tree is the minimum spanning tree of a Euclidean complete graph. It is also possible to define graphs by c
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https://en.wikipedia.org/wiki/X-Video%20Motion%20Compensation
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X-Video Motion Compensation (XvMC), is an extension of the X video extension (Xv) for the X Window System. The XvMC API allows video programs to offload portions of the video decoding process to the GPU video-hardware. In theory this process should also reduce bus bandwidth requirements. Currently, the supported portions to be offloaded by XvMC onto the GPU are motion compensation (mo comp) and inverse discrete cosine transform (iDCT) for MPEG-2 video. XvMC also supports offloading decoding of mo comp, iDCT, and VLD ("Variable-Length Decoding", more commonly known as "slice level acceleration") for not only MPEG-2 but also MPEG-4 ASP video on VIA Unichrome (S3 Graphics Chrome Series) hardware.
XvMC was the first UNIX equivalent of the Microsoft Windows DirectX Video Acceleration (DxVA) API. Popular software applications known to take advantage of XvMC include MPlayer, MythTV, and xine.
Device drivers
Each hardware video GPU capable of XvMC video acceleration requires a X11 software device driver to enable these features.
Hardware manufacturers
Nvidia
There are currently three X11 Nvidia drivers available: a 2D-only open source but obfuscated driver maintained by Nvidia called nv, a proprietary binary driver by Nvidia, and an open source driver based on reverse engineering of the binary driver developed by the Linux community called Nouveau. Nouveau is not pursuing XvMC support, the 2D nv driver does not support XvMC, and the official proprietary binary driver by Nvidia only supports MPEG-2 offloading (mo comp and iDCT) on hardware up to and including the GeForce 7000 series.
VIA
VIA provides open source device drivers for some of its VIA Unichrome (S3 Graphics Chrome Series) hardware, supporting offloading of MPEG-2 and MPEG-4 ASP video.
Thanks to VLD level of decoding VIA offloads much more decoding tasks from CPU than GPUs supporting iDCT or mo comp levels only. Keep in mind that not all devices are supported and there are some other caveats.
Intel
Intel pr
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https://en.wikipedia.org/wiki/Pythagorean%20means
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In mathematics, the three classical Pythagorean means are the arithmetic mean (AM), the geometric mean (GM), and the harmonic mean (HM). These means were studied with proportions by Pythagoreans and later generations of Greek mathematicians because of their importance in geometry and music.
Definition
They are defined by:
Properties
Each mean, , has the following properties:
First-order homogeneity
Invariance under exchange
for any and .
Monotonicity
Idempotence
Monotonicity and idempotence together imply that a mean of a set always lies between the extremes of the set:
The harmonic and arithmetic means are reciprocal duals of each other for positive arguments,
while the geometric mean is its own reciprocal dual:
Inequalities among means
There is an ordering to these means (if all of the are positive)
with equality holding if and only if the are all equal.
This is a generalization of the inequality of arithmetic and geometric means and a special case of an inequality for generalized means. The proof follows from the arithmetic–geometric mean inequality, , and reciprocal duality ( and are also reciprocal dual to each other).
The study of the Pythagorean means is closely related to the study of majorization and Schur-convex functions. The harmonic and geometric means are concave symmetric functions of their arguments, and hence Schur-concave, while the arithmetic mean is a linear function of its arguments and hence is both concave and convex.
History
Almost everything that we know about the Pythagorean means came from arithmetic handbooks written in the first and second century. Nicomachus of Gerasa says that they were “acknowledged by all the ancients, Pythagoras, Plato and Aristotle.” Their earliest known use is a fragment of the Pythagorean philosopher Archytas of Tarentum:
The name "harmonic mean", according to Iamblichus, was coined by Archytas and Hippasus. The Pythagorean means also appear in Plato's Timaeus. Another evidence of t
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https://en.wikipedia.org/wiki/POWER3
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The POWER3 is a microprocessor, designed and exclusively manufactured by IBM, that implemented the 64-bit version of the PowerPC instruction set architecture (ISA), including all of the optional instructions of the ISA (at the time) such as instructions present in the POWER2 version of the POWER ISA but not in the PowerPC ISA. It was introduced on 5 October 1998, debuting in the RS/6000 43P Model 260, a high-end graphics workstation. The POWER3 was originally supposed to be called the PowerPC 630 but was renamed, probably to differentiate the server-oriented POWER processors it replaced from the more consumer-oriented 32-bit PowerPCs. The POWER3 was the successor of the P2SC derivative of the POWER2 and completed IBM's long-delayed transition from POWER to PowerPC, which was originally scheduled to conclude in 1995. The POWER3 was used in IBM RS/6000 servers and workstations at 200 MHz. It competed with the Digital Equipment Corporation (DEC) Alpha 21264 and the Hewlett-Packard (HP) PA-8500.
Description
The POWER3 was based on the PowerPC 620, an earlier 64-bit PowerPC implementation that was late, under-performing and commercially unsuccessful. Like the PowerPC 620, the POWER3 has three fixed-point units, but the single floating-point unit (FPU) was replaced with two floating-point fused multiply–add units, and an extra load-store unit was added (for a total of two) to improve floating-point performance. The POWER3 is a superscalar design that executed instructions out of order. It has a seven-stage integer pipeline, a minimal eight-stage load/store pipeline and a ten-stage floating-point pipeline.
The front end consists of two stages: fetch and decode. During the first stage, eight instructions were fetched from a 32 KB instruction cache and placed in a 12-entry instruction buffer. During the second stage, four instructions were taken from the instruction buffer, decoded, and issued to instruction queues. Restrictions on instruction issue are few: of the two i
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https://en.wikipedia.org/wiki/Trunk%20prefix
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A trunk prefix is a digit sequence to be dialled before a telephone number to initiate a telephone call for the purpose of selecting an appropriate telecommunications circuit by which the call is to be routed.
Making a domestic (national) telephone call usually requires the dialling of a single or two-digit national trunk prefix preceding any area codes and the destination subscriber number. In most countries, the trunk prefix is 0.
For international telephone calls, the national trunk prefix is not dialled; instead, an international trunk prefix (or "+") is typically required, followed by the destination's country code.
Example
This example assumes that a call is to be made to a customer in the Australian state of Queensland with the local number 3333 3333 and the area code 7.
A caller from outside Australia must dial the international call prefix of the originating country and the country code (61 for Australia), then the area code (7), and then the local subscriber number. Therefore, a caller in the UK must dial 00 61 7 3333 3333, while a caller in the US must dial 011 61 7 3333 3333.
Calling inter-area (within Australia) (e.g. from Western Australia with area code 8), a caller need not dial an international trunk prefix or a country code. Instead, the caller must at least dial the Australian trunk prefix (0) followed by the area code (7) and then the local subscriber number: 07 3333 3333. Calling from within the Queensland (7) area, a caller need only dial the telephone number: 3333 3333.
However, since the early 21st century, the majority of telephone systems worldwide can recognise the area of origin of the call, its direction and destination to facilitate communication faster. If the full international number is used, then this full international number may be dialled from nearly any telephone within a recognisable landline or mobile network. This has become particularly vital for users of mobile phones.
When conducting business, e.g., for display on
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https://en.wikipedia.org/wiki/List%20of%20cohomology%20theories
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This is a list of some of the ordinary and generalized (or extraordinary) homology and cohomology theories in algebraic topology that are defined on the categories of CW complexes or spectra. For other sorts of homology theories see the links at the end of this article.
Notation
S = π = S0 is the sphere spectrum.
Sn is the spectrum of the n-dimensional sphere
SnY = Sn∧Y is the nth suspension of a spectrum Y.
[X,Y] is the abelian group of morphisms from the spectrum X to the spectrum Y, given (roughly) as homotopy classes of maps.
[X,Y]n = [SnX,Y]
[X,Y]* is the graded abelian group given as the sum of the groups [X,Y]n.
πn(X) = [Sn, X] = [S, X]n is the nth stable homotopy group of X.
π*(X) is the sum of the groups πn(X), and is called the coefficient ring of X when X is a ring spectrum.
X∧Y is the smash product of two spectra.
If X is a spectrum, then it defines generalized homology and cohomology theories on the category of spectra as follows.
Xn(Y) = [S, X∧Y]n = [Sn, X∧Y] is the generalized homology of Y,
Xn(Y) = [Y, X]−n = [S−nY, X] is the generalized cohomology of Y
Ordinary homology theories
These are the theories satisfying the "dimension axiom" of the Eilenberg–Steenrod axioms that the homology of a point vanishes in dimension other than 0. They are determined by an abelian coefficient group G, and denoted by H(X, G) (where
G is sometimes omitted, especially if it is Z). Usually G is the integers, the rationals, the reals, the complex numbers, or the integers mod a prime p.
The cohomology functors of ordinary cohomology theories are represented by Eilenberg–MacLane spaces.
On simplicial complexes, these theories coincide with singular homology and cohomology.
Homology and cohomology with integer coefficients.
Spectrum: H (Eilenberg–MacLane spectrum of the integers.)
Coefficient ring: πn(H) = Z if n = 0, 0 otherwise.
The original homology theory.
Homology and cohomology with rational (or real or complex) coefficients.
Spectrum: HQ (Eilenberg–Mac
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https://en.wikipedia.org/wiki/Mechanical%20engineering%20technology
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Mechanical engineering technology is the application of engineering principles and technological developments for the creation of useful products and production machinery.
Technologists
Mechanical engineering technologists are expected to apply current technologies and principles from machine and product design, production and material and manufacturing processes.
Expandable specialties may include aerospace, automotive, energy, nuclear, petroleum, manufacturing, product development, and industrial design.
Mechanical engineering technologists can have many different titles, including in the United States:
Mechanical Engineering Technologist
Mechanical Engineer
Product Engineering Technologist
Mechanical Designer
Product Development Engineering Technologist
Manufacturing Engineering Technologist
Training
Mechanical Engineering Technology coursework is less theoretical, and more application based than a mechanical engineering degree. This is evident through the additional laboratory coursework required for a degree. The ability to apply concepts from the chemical engineering and electrical engineering fields is important.
Some university Mechanical Engineering Technology degree programs require mathematics through differential equations and statistics. Most courses involve algebra and calculus.
Oftentimes, a MET graduate could get hired as an engineer; job titles may include Mechanical Engineer and Manufacturing Engineer.
In the U.S. it is possible to get an associates or bachelor's degree. Individuals with a bachelor's degree in engineering technology may continue on to complete the E.I.T. (Engineer in Training) examination to eventually become Professional Engineers if the program is ABET accredited.
Applications
Software tools such as Finite Element Analysis (FEA) and Computational Fluid Dynamics (CFD) are often used to analyze parts and assemblies. 3D models can be made to represent parts and assemblies with computer-aided design (CAD) software
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https://en.wikipedia.org/wiki/Allan%20M.A.%20McLean
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Allan Marcus Atkinson McLean (September 27, 1891 – April 27, 1969) was a Canadian businessman who co-managed Connors Brothers Limited, a New Brunswick based fish processing business, and a politician who served as a member of the House of Commons of Canada.
Biography
Born in Bristol, New Brunswick, the third of four children, he is a descendant of Dutch United Empire Loyalists on his mother's side, and Scots émigrés to Cape Breton Island on his father's side. In 1923, McLean, along with elder brother Neil, took control of the Connors Bros. fish processing business that had been founded in Blacks Harbour, New Brunswick by Lewis and Patrick Connors in 1894.
Much of the McLean brothers' lives were spent developing the fishing industry centered around New Brunswick's Passamaquoddy Bay in southwestern New Brunswick. Largely focused on canning herring, Connors Brothers also served the northeastern United States' Roman Catholic 'fish on Friday' market by shipping haddock and pollock to New England markets. Connors Brothers was sold to the George Weston Limited conglomerate headquartered in Toronto in approximately 1966 as Neil and Allan McLean approached 80 years of age.
Both McLean brothers were active in politics. Neil McLean (1885–1967) served as president of the New Brunswick Liberal Party for many years and then as a member of the Senate of Canada. Allan McLean ran for election to the House of Commons of Canada in 1961 in the riding of Charlotte County, New Brunswick, was elected and re-elected twice until retiring in 1968. He died of a heart attack in Florida in 1969.
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https://en.wikipedia.org/wiki/Rank%20correlation
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In statistics, a rank correlation is any of several statistics that measure an ordinal association—the relationship between rankings of different ordinal variables or different rankings of the same variable, where a "ranking" is the assignment of the ordering labels "first", "second", "third", etc. to different observations of a particular variable. A rank correlation coefficient measures the degree of similarity between two rankings, and can be used to assess the significance of the relation between them. For example, two common nonparametric methods of significance that use rank correlation are the Mann–Whitney U test and the Wilcoxon signed-rank test.
Context
If, for example, one variable is the identity of a college basketball program and another variable is the identity of a college football program, one could test for a relationship between the poll rankings of the two types of program: do colleges with a higher-ranked basketball program tend to have a higher-ranked football program? A rank correlation coefficient can measure that relationship, and the measure of significance of the rank correlation coefficient can show whether the measured relationship is small enough to likely be a coincidence.
If there is only one variable, the identity of a college football program, but it is subject to two different poll rankings (say, one by coaches and one by sportswriters), then the similarity of the two different polls' rankings can be measured with a rank correlation coefficient.
As another example, in a contingency table with low income, medium income, and high income in the row variable and educational level—no high school, high school, university—in the column variable), a rank correlation measures the relationship between income and educational level.
Correlation coefficients
Some of the more popular rank correlation statistics include
Spearman's ρ
Kendall's τ
Goodman and Kruskal's γ
Somers' D
An increasing rank correlation coefficient implies increa
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https://en.wikipedia.org/wiki/Irwin%20Stone
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Irwin Stone (1907–1984) was an American biochemist, chemical engineer, and writer. He was the first to use ascorbic acid in the food processing industry as a preservative, and originated and published the hypothesis that humans require much larger amounts of Vitamin C for optimal health than is necessary to prevent scurvy.
Food preservative work
In 1934, Stone, while director of the enzyme and fermentation research laboratory for the Wallerstein Company, worked on the antioxidant properties of ascorbate (also known as Vitamin C), which had then recently been described by Albert Szent-Györgyi only two years earlier. He was awarded 26 patents in industrial chemistry, mainly related to fermentation science, pharmaceutical techniques, and nutrient cultivation.
He discovered he could use ascorbate to keep foodstuffs fresh for longer, limiting the effects of exposure to air and oxidation. Stone obtained the first patents on an industrial application of ascorbic acid with three patent applications filed in 1935 and granted in 1939 and 1940.
Hypoascorbemia hypothesis
Stone's research in ascorbic acid continued and led to his interest in the disease, scurvy. By the late 1950s, Stone had formulated his hypothesis that scurvy was not a dietary disturbance, but potentially a flaw in human genetics that had suppressed an essential part of the mammalian biochemistry and had been misunderstood by nutritionists. He proposed the name hypoascorbemia for the effects of this genetic defect. He proposed that ascorbate was not a vitamin required only in trace amounts, but was required by humans in relatively large daily quantities. He produced four papers, between 1965 and 1967, describing what he considered the true human requirement for ascorbate.
Stone experienced great difficulty in getting his ideas published. However, following his retirement from his position as chemist from the Wallerstein company in 1971, he worked full-time on studying ascorbate. In 1972 he published the
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https://en.wikipedia.org/wiki/Resonance%20chamber
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A resonance chamber uses resonance to enhance the transfer of energy from a sound source (e.g. a vibrating string) to the air. The chamber has interior surfaces which reflect an acoustic wave. When a wave enters the chamber, it bounces back and forth within the chamber with low loss (See standing wave). As more wave energy enters the chamber, it combines with and reinforces the standing wave, increasing its intensity.
Since the resonance chamber is an enclosed space that has an opening where the sound wave enters and exits after bouncing off of the internal walls producing resonance, commonly acoustic resonance as in many musical instruments (see Sound board (music)), the material of the chamber, particularly that of the actual internal walls, its shape and the position of the opening, as well as the finish (porosity) of the internal walls are contributing factors for the final resulting sound produced.
See also
Cavity resonator (electrical version)
Resonance
Sounding box
Waveguide
Sources
Acoustics
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https://en.wikipedia.org/wiki/Rowbottom%20cardinal
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In set theory, a Rowbottom cardinal, introduced by , is a certain kind of large cardinal number.
An uncountable cardinal number is said to be - Rowbottom if for every function f: [κ]<ω → λ (where λ < κ) there is a set H of order type that is quasi-homogeneous for f, i.e., for every n, the f-image of the set of n-element subsets of H has < elements. is Rowbottom if it is - Rowbottom.
Every Ramsey cardinal is Rowbottom, and every Rowbottom cardinal is Jónsson. By a theorem of Kleinberg, the theories ZFC + “there is a Rowbottom cardinal” and ZFC + “there is a Jónsson cardinal” are equiconsistent.
In general, Rowbottom cardinals need not be large cardinals in the usual sense: Rowbottom cardinals could be singular. It is an open question whether ZFC + “ is Rowbottom” is consistent. If it is, it has much higher consistency strength than the existence of a Rowbottom cardinal. The axiom of determinacy does imply that is Rowbottom (but contradicts the axiom of choice).
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https://en.wikipedia.org/wiki/J%C3%B3nsson%20cardinal
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In set theory, a Jónsson cardinal (named after Bjarni Jónsson) is a certain kind of large cardinal number.
An uncountable cardinal number κ is said to be Jónsson if for every function there is a set of order type such that for each , restricted to -element subsets of omits at least one value in .
Every Rowbottom cardinal is Jónsson. By a theorem of Eugene M. Kleinberg, the theories ZFC + “there is a Rowbottom cardinal” and ZFC + “there is a Jónsson cardinal” are equiconsistent. William Mitchell proved, with the help of the Dodd-Jensen core model that the consistency of the existence of a Jónsson cardinal implies the consistency of the existence of a Ramsey cardinal, so that the existence of Jónsson cardinals and the existence of Ramsey cardinals are equiconsistent.
In general, Jónsson cardinals need not be large cardinals in the usual sense: they can be singular. But the existence of a singular Jónsson cardinal is equiconsistent to the existence of a measurable cardinal. Using the axiom of choice, a lot of small cardinals (the , for instance) can be proved to be not Jónsson. Results like this need the axiom of choice, however: The axiom of determinacy does imply that for every positive natural number n, the cardinal is Jónsson.
A Jónsson algebra is an algebra with no proper subalgebras of the same cardinality. (They are unrelated to Jónsson–Tarski algebras). Here an algebra means
a model for a language with a countable number of function symbols, in other words a set with a countable number of functions from finite products of the set to itself. A cardinal is a Jónsson cardinal if and only if there are no Jónsson algebras of that cardinality. The existence of Jónsson functions shows that if algebras are allowed to have infinitary operations, then there are no analogues of Jónsson cardinals.
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https://en.wikipedia.org/wiki/Vinopolis
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Vinopolis was a commercial visitor attraction in Southwark, London, England, operated by Wineworld, London that presented the subject of wine and oenology through exhibits and wine tastings. Vinopolis closed permanently at the end of 2015.
Overview
Vinopolis was located at Bankside, to the east of Southwark Bridge , and close to London Bridge on the southern side of the River Thames. There was an attached restaurant, Cantina Vinopolis, and wine was available for sale at the attached Laithwaites Wine Store. Vinopolis spanned and was devoted to the world of wine, including its history, development, and taste. Within the complex, there was a specialist whisky retailer, The Whisky Exchange, which offered a range of whiskies and other spirits. The Whisky Exchange also organized various whisky-tasting events throughout the year at Vinopolis.
History
Vinopolis was developed by the wine merchant Duncan Vaughan-Arbuckle. He chose a site beneath the arches of a Victorian railway viaduct that was built in 1866 by the Southeastern Railway Company to carry an extension line from London Bridge Station over the Thames to the north bank.
Vinopolis opened on 23 July 1999. Its first program was a four-hour guided tour through static wine displays with tastings. The business evolved over the years, and at the time it closed, it operated as both a wine tour and a corporate events venue.
Offerings
In July 2008, the attraction of the "Authentic Caribbean Rum Experience" was opened, which allowed attendees to sample a selection of Caribbean premium rums.
The last range of offerings was put in place in Autumn 2012. The site featured wines from around the world. Three self-guided "experience packages" were offered, called "essential", "classic" and "quintessential". Group packages and group guided tours were also available. The wines were served from enomatic dispensers to prevent spoilage.
Throughout the year, Vinopolis hosted a range of events featuring wine, spirits, and food. T
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https://en.wikipedia.org/wiki/CRI%20Middleware
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(formerly CSK Research Institute Corp.) is a Japanese developer providing middleware for use in the video game industry. From the early nineties, CRI was a video game developer, but shifted focus in 2001.
History
CRI started out as CSK Research Institute, subsidiary of CSK, producing video games for the Mega Drive/Genesis. It went on to develop games for the Sega Saturn and Dreamcast before it was incorporated as CRI Middleware in 2001. In 2006, CRI Middleware introduced the CRIWARE brand.
Games
Developed
Published
CRIWARE
CRI ADX
CRI ADX is a streamed audio format which allows for multiple audio streams, seamless looping and continuous playback (allowing two or more files to be crossfaded or played in sequence) with low, predictable CPU usage. The format uses the ADPCM framework.
CRI Sofdec
CRI Sofdec is a streamed video format supporting up to 24bit color which includes multistreaming and seamless playback with a frame rate of up to 60 frames per second. It is essentially a repackaging of MPEG-1/MPEG-2 video with CRI's proprietary ADX codec for audio playback.
CRI Clipper
CRI Clipper is an automated lip-syncing program which analyzes waveforms and outputs an appropriate lip pattern into a text file, for later substitution into the facial animations of the (in-game) speaker.
CRI ROFS
CRI ROFS is a file management system for handling a virtual disc image, an extension of the CD-ROM standard. It has no limitations on file name format, or number of directories or files, and has been designed with compatibility with ADX and Sofdec in mind.
CRI Sound Factory
CRI Sound Factory is a GUI-based video game audio tool for effective sound design without input from programmers. It has support for the previewing and playback of generated audio.
CRI Movie Encode
CRI Movie Encode is a video encoding service by which CRI generates Sofdec or MPEG files from other media. For a fee (designated by the length of the file to be encoded), files are converted to the desired fo
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https://en.wikipedia.org/wiki/Inclusion%20%28taxonomy%29
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In taxonomy, inclusion is the process whereby two species that were believed to be distinct are found in fact to be the same and are thus combined as one species. Which name is kept for this unified species is sometimes a cause of debate, but generally it is the earlier-named one, and the other species is said to be "included" within this one.
Inclusion is far more common in paleontology than more recent biology, although it is not unheard of in the latter. When it occurs with more recent or modern species, it is usually the result of a species with wide geographical dispersion.
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https://en.wikipedia.org/wiki/Advanced%20process%20control
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In control theory, advanced process control (APC) refers to a broad range of techniques and technologies implemented within industrial process control systems. Advanced process controls are usually deployed optionally and in addition to basic process controls. Basic process controls are designed and built with the process itself, to facilitate basic operation, control and automation requirements. Advanced process controls are typically added subsequently, often over the course of many years, to address particular performance or economic improvement opportunities in the process.
Process control (basic and advanced) normally implies the process industries, which includes chemicals, petrochemicals, oil and mineral refining, food processing, pharmaceuticals, power generation, etc. These industries are characterized by continuous processes and fluid processing, as opposed to discrete parts manufacturing, such as automobile and electronics manufacturing. The term process automation is essentially synonymous with process control.
Process controls (basic as well as advanced) are implemented within the process control system, which may mean a distributed control system (DCS), programmable logic controller (PLC), and/or a supervisory control computer. DCSs and PLCs are typically industrially hardened and fault-tolerant. Supervisory control computers are often not hardened or fault-tolerant, but they bring a higher level of computational capability to the control system, to host valuable, but not critical, advanced control applications. Advanced controls may reside in either the DCS or the supervisory computer, depending on the application. Basic controls reside in the DCS and its subsystems, including PLCs.
Types of Advanced Process Control
Following is a list of well known types of advanced process control:
Advanced regulatory control (ARC) refers to several proven advanced control techniques, such as override or adaptive gain (but in all cases, "regulating o
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https://en.wikipedia.org/wiki/Dilation%20%28operator%20theory%29
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In operator theory, a dilation of an operator T on a Hilbert space H is an operator on a larger Hilbert space K, whose restriction to H composed with the orthogonal projection onto H is T.
More formally, let T be a bounded operator on some Hilbert space H, and H be a subspace of a larger Hilbert space H' . A bounded operator V on H' is a dilation of T if
where is an orthogonal projection on H.
V is said to be a unitary dilation (respectively, normal, isometric, etc.) if V is unitary (respectively, normal, isometric, etc.). T is said to be a compression of V. If an operator T has a spectral set , we say that V is a normal boundary dilation or a normal dilation if V is a normal dilation of T and .
Some texts impose an additional condition. Namely, that a dilation satisfy the following (calculus) property:
where f(T) is some specified functional calculus (for example, the polynomial or H∞ calculus). The utility of a dilation is that it allows the "lifting" of objects associated to T to the level of V, where the lifted objects may have nicer properties. See, for example, the commutant lifting theorem.
Applications
We can show that every contraction on Hilbert spaces has a unitary dilation. A possible construction of this dilation is as follows. For a contraction T, the operator
is positive, where the continuous functional calculus is used to define the square root. The operator DT is called the defect operator of T. Let V be the operator on
defined by the matrix
V is clearly a dilation of T. Also, T(I - T*T) = (I - TT*)T and a limit argument imply
Using this one can show, by calculating directly, that V is unitary, therefore a unitary dilation of T. This operator V is sometimes called the Julia operator of T.
Notice that when T is a real scalar, say , we have
which is just the unitary matrix describing rotation by θ. For this reason, the Julia operator V(T) is sometimes called the elementary rotation of T.
We note here that in the above discussi
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https://en.wikipedia.org/wiki/Reinnervation
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Reinnervation is the restoration, either by spontaneous cellular regeneration or by surgical grafting, of nerve supply to a body part from which it has been lost or damaged.
See also
Denervation
Neuroregeneration
Targeted reinnervation
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https://en.wikipedia.org/wiki/Backward%20masking
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The concept of backward masking originated in psychoacoustics, referring to temporal masking of quiet sounds that occur moments before a louder sound.
In cognitive psychology, visual backward masking involves presenting one visual stimulus (a "mask" or "masking stimulus") immediately after a brief (usually 30 ms) "target" visual stimulus resulting in a failure to consciously perceive the first stimulus. It is widely used in psychophysiological studies on fear and phobias that investigate the preattentive nonconscious reactions to fear-relevant stimuli.
It is unknown how a later stimulus is able to block an earlier one. However, one theory for this phenomenon, known as the dual channel interaction theory, proposes that a fast signal created by the second stimulus is able to catch up to and overcome a slower signal sent from the first impulse. A similar phenomenon can occur when a masking stimulus precedes a target stimulus rather than follows it: this is known as forward masking, or visual forward masking when the stimulus is visual. While not consciously perceived, the masked stimulus can nevertheless still have an effect on cognitive processes such as context interpretation. It has been shown that visually masked stimuli can elicit motor responses in simple reaction-time tasks (e.g. response priming) independent of their conscious visibility.
It is a widespread belief that masked stimuli can be used for psychological manipulation (see subliminal messages, psychorama). However, the empirical evidence for subliminal persuasion is limited.
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https://en.wikipedia.org/wiki/List%20of%20SAP%20products
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This presents a partial list of products of the enterprise software company SAP SE.
Major units
SAP S/4HANA (Enterprise Resource Planning on-premise and cloud)
SAP Business ByDesign (SME Cloud Enterprise Resource Planning)
SAP Business One (B1 on HANA) (Small enterprise Enterprise Resource Planning)
SAP CRM (Customer Relationship Management)
SAP ERP (Enterprise Resource Planning)
SAP PLM (Product Lifecycle Management)
SAP SCM (Supply Chain Management)
SAP SRM (Supplier Relationship Management)
Business software
SAP Advanced Data Migration (ADP)
SAP Advanced Planner and Optimizer
SAP Analytics Cloud (SAC)
SAP Advanced Business Application Programming (ABAP)
SAP Apparel and Footwear Solution (AFS)
SAP Business Information Warehouse (BW)
SAP Business ByDesign (ByD)
SAP Business Explorer (Bex)
SAP BusinessObjects Lumira
SAP BusinessObjects Web Intelligence (Webi)
SAP Business One
SAP Business Partner Screening
SAP Business Intelligence (BI)
SAP Business Workflow
SAP Catalog Content Management ()
SAP Cloud for Customer (C4C)
SAP Cost Center Accounting (CCA)
SAP Convergent Charging (CC)
SAP Converged Cloud
SAP Data Warehouse Cloud (DWC)
SAP Design Studio
SAP PRD2(P2)
SAP Enterprise Buyer Professional (EBP)
SAP Enterprise Learning
SAP Portal (EP)
SAP Exchange Infrastructure (XI) (From release 7.0 onwards, SAP XI has been renamed as SAP Process Integration (SAP PI))
SAP Extended Warehouse Management (EWM)
SAP FICO
SAP BPC (Business Planning and Consolidation, formerly OutlookSoft)
SAP GRC (Governance, Risk and Compliance)
SAP EHSM (Environment Health & Safety Management)
Enterprise Central Component (ECC)
SAP ERP
SAP HANA (formerly known as High-performance Analytics Appliance)
SAP Human Resource Management Systems (HRMS)
SAP SuccessFactors
SAP Litmos Training Cloud
SAP Information Design Tool (IDT)
SAP Integrated Business Planning (IBP)
SAP Internet Transaction Server (ITS)
SAP Incentive and Commission Management (ICM)
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https://en.wikipedia.org/wiki/Signal-to-quantization-noise%20ratio
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Signal-to-quantization-noise ratio (SQNR or SNqR) is widely used quality measure in analysing digitizing schemes such as pulse-code modulation (PCM). The SQNR reflects the relationship between the maximum nominal signal strength and the quantization error (also known as quantization noise) introduced in the analog-to-digital conversion.
The SQNR formula is derived from the general signal-to-noise ratio (SNR) formula:
where:
is the probability of received bit error
is the peak message signal level
is the mean message signal level
As SQNR applies to quantized signals, the formulae for SQNR refer to discrete-time digital signals. Instead of , the digitized signal will be used. For quantization steps, each sample, requires bits. The probability distribution function (PDF) represents the distribution of values in and can be denoted as . The maximum magnitude value of any is denoted by .
As SQNR, like SNR, is a ratio of signal power to some noise power, it can be calculated as:
The signal power is:
The quantization noise power can be expressed as:
Giving:
When the SQNR is desired in terms of decibels (dB), a useful approximation to SQNR is:
where is the number of bits in a quantized sample, and is the signal power calculated above. Note that for each bit added to a sample, the SQNR goes up by approximately 6 dB ().
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https://en.wikipedia.org/wiki/Paramecia%20%28alga%29
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Paramecia is a non-mineralized Ediacaran alga with a differentiated, compartmentalized thallus. This alga probably had multiple phases in its lifecycle, as possible reproductive structures have been identified.
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https://en.wikipedia.org/wiki/Igor%20Pak
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Igor Pak () (born 1971, Moscow, Soviet Union) is a professor of mathematics at the University of California, Los Angeles, working in combinatorics and discrete probability. He formerly taught at the Massachusetts Institute of Technology and the University of Minnesota, and he is best known for his bijective proof of the hook-length formula for the number of Young tableaux, and his work on random walks. He was a keynote speaker alongside George Andrews and Doron Zeilberger at the 2006 Harvey Mudd College Mathematics Conference on Enumerative Combinatorics.
Pak is an Associate Editor for the journal Discrete Mathematics. He gave a Fejes Tóth Lecture at the University of Calgary in February 2009.
In 2018, he was an invited speaker at the International Congress of Mathematicians in Rio de Janeiro.
Background
Pak went to Moscow High School № 57. After graduating, he worked for a year at Bank Menatep.
He did his undergraduate studies at Moscow State University. He was a PhD student of Persi Diaconis at Harvard University, where he received a doctorate in Mathematics in 1997, with a thesis titled Random Walks on Groups: Strong Uniform Time Approach. Afterwards, he worked with László Lovász as a postdoc at Yale University. He was a fellow at the Mathematical Sciences Research Institute and a long-term visitor at the Hebrew University of Jerusalem.
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https://en.wikipedia.org/wiki/Mr.%20Horsepower
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Mr. Horsepower is the cartoon mascot and logo of Clay Smith Cams, an auto shop established in 1931. He is a sneering, cigar-smoking bird with red feathers and a yellow beak. The image is a caricature of legendary hot rod guru Clay Smith (1915–1954), well known for his red hair. Mr. Horsepower is rarely without a cigar, but when he is, he has a "cigar replacement", such as a candy cane for the holidays. The character is well known among car aficionados.
Origins
The origins of Clay Smith Cams can be traced back to the 1930s, when Kansas racing driver Pete Bertrand opened a car tuning shop at Long Beach. Clay Smith, just a boy at the time, was employed by Bertrand until the latter's death from pneumonia in 1942. Smith, himself a racing enthusiast, took over the company and continued producing precision engine parts, especially camshafts. In 1952, Smith teamed with Troy Ruttman to win the Indianapolis 500. In 1954, he was killed by a race car that he had helped prepare, while working in the pits on the infield at DuQuoin, Illinois. Clay was one of the early specialist camshaft grinders, and built many race winning engines, for various types of race classes and machines.
Originally a mascot painted on Clay Smith's boats and race cars, Mr. Horsepower became the company logo as the reputation of Smith's fine-tuned auto parts spread. Today, the Mr. Horsepower logo is commonly seen as a car decal, tattoo, t-shirt logo, car mat, or garage clock.
Some people have confused Mr. Horsepower with the cartoon character Woody Woodpecker. The notable points of contrast are that Woody Woodpecker's beak is curved but smooth on top and bottom, and his head-feathers form a well-contained "V" shape in early iterations or a sprout of sorts in newer iterations. Mr. Horsepower also has a similar appearance to the Thrush Exhaust logo. The Thrush logo has hot pink feathers, no gaps between the teeth and lacks the cigar.
Popular culture
The logo has appeared in video games, most prominently
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https://en.wikipedia.org/wiki/Carbon-13%20nuclear%20magnetic%20resonance
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Carbon-13 (C13) nuclear magnetic resonance (most commonly known as carbon-13 NMR spectroscopy or 13C NMR spectroscopy or sometimes simply referred to as carbon NMR) is the application of nuclear magnetic resonance (NMR) spectroscopy to carbon. It is analogous to proton NMR ( NMR) and allows the identification of carbon atoms in an organic molecule just as proton NMR identifies hydrogen atoms. 13C NMR detects only the isotope. The main carbon isotope, does not produce an NMR signal. Although ca. 1 mln. times less sensitive than 1H NMR spectroscopy, 13C NMR spectroscopy is widely used for characterizing organic and organometallic compounds, primarily because 1H-decoupled 13C-NMR spectra are more simple, have a greater sensitivity to differences in the chemical structure, and, thus, are better suited for identifying molecules in complex mixtures. At the same time, such spectra lack quantitative information about the atomic ratios of different types of carbon nuclei, because nuclear Overhauser effect used in 1H-decoupled 13C-NMR spectroscopy enhances the signals from carbon atoms with a larger number of hydrogen atoms attached to them more than from carbon atoms with a smaller number of H's, and because full relaxation of 13C nuclei is usually not attained (for the sake of reducing the exaperiment time), and the nuclei with shorter relaxation times produce more intense signals.
The major isotope of carbon, the 12C isotope, has a spin quantum number of zero and so is not magnetically active and therefore not detectable by NMR. 13C, with a spin quantum number of 1/2, is not abundant (1.1%), whereas other popular nuclei are 100% abundant, e.g. 1H, 19F, 31P.
Receptivity
13C NMR spectroscopy is much less sensitive (ca. by 4 orders of magnitude) to carbon than 1H NMR spectroscopy is to hydrogen, because of the lower abundance (1.1%) of 13C compared to 1H (>99%), and because of a lower(0.702 vs. 2.8) nuclear magnetic moment. Stated equivalently, the gyromagnetic ratio
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https://en.wikipedia.org/wiki/Bogor%20Botanical%20Gardens
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The Bogor Botanical Gardens () is a botanical garden located in Bogor, Indonesia, 60 km south of central Jakarta. It is currently operated by the National Research and Innovation Agency. The garden is located in the city center and adjoin the presidential palace compound of Istana Bogor. It covers an area of and contains 13,983 different kinds of trees and plants of various origin. The geographic position of Bogor means it rains almost daily, even in the dry season. This makes the garden an advantageous location for the cultivation of tropical plants.
Founded in 1817 by the order of the government of the Dutch East Indies, the garden thrived under the leadership of many renowned botanists including Johannes Elias Teijsmann, Rudolph Herman Christiaan Carel Scheffer, and Melchior Treub. Since its foundation, the Bogor botanical garden has served as a major research center for agriculture and horticulture. It is the oldest botanical garden in Southeast Asia.
History
Background
The area that is now Bogor Botanical Gardens was part of the samida (man-made forest) that was established at least around the era when Sri Baduga Maharaja (Prabu Siliwangi, 1474–1513) ruled the Sunda Kingdom, as written in the Batutulis inscription. This forest was created to protect seeds of rare trees. The forest remained neglected after the Sundanese kingdom was destroyed in the 16th century. In 1744 the Dutch East India Company established a garden and mansion at the site of the present botanical gardens in Buitenzorg (now known as Bogor).
After the successful British invasion of Java in 1811, Stamford Raffles was appointed as the island's lieutenant-governor, and he took Buitenzorg Palace as his residence. During his rule in the palace, he had the garden re-landscaped into English-style garden. His wife, Olivia Mariamne Raffles, died in Buitenzorg on November 26, 1814, and was buried in Batavia. A memorial monument was built in the garden, as a commemoration for her.
's Lands Planten
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https://en.wikipedia.org/wiki/Glyoxylate%20cycle
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The glyoxylate cycle, a variation of the tricarboxylic acid cycle, is an anabolic pathway occurring in plants, bacteria, protists, and fungi. The glyoxylate cycle centers on the conversion of acetyl-CoA to succinate for the synthesis of carbohydrates. In microorganisms, the glyoxylate cycle allows cells to use two carbons (C2 compounds), such as acetate, to satisfy cellular carbon requirements when simple sugars such as glucose or fructose are not available. The cycle is generally assumed to be absent in animals, with the exception of nematodes at the early stages of embryogenesis. In recent years, however, the detection of malate synthase (MS) and isocitrate lyase (ICL), key enzymes involved in the glyoxylate cycle, in some animal tissue has raised questions regarding the evolutionary relationship of enzymes in bacteria and animals and suggests that animals encode alternative enzymes of the cycle that differ in function from known MS and ICL in non-metazoan species.
Plants as well as some algae and bacteria can use acetate as the carbon source for the production of carbon compounds. Plants and bacteria employ a modification of the TCA cycle called the glyoxylate cycle to produce four carbon dicarboxylic acid from two carbon acetate units. The glyoxylate cycle bypasses the two oxidative decarboxylation reactions of the TCA cycle and directly converts isocitrate through isocitrate lyase and malate synthase into malate and succinate.
The glyoxylate cycle was discovered in 1957 at the University of Oxford by Sir Hans Kornberg and his mentor Hans Krebs, resulting in a Nature paper Synthesis of Cell Constituents from C2-Units by a Modified Tricarboxylic Acid Cycle.
Similarities with TCA cycle
The glyoxylate cycle uses five of the eight enzymes associated with the tricarboxylic acid cycle: citrate synthase, aconitase, succinate dehydrogenase, fumarase, and malate dehydrogenase. The two cycles differ in that in the glyoxylate cycle, isocitrate is converted into glyoxy
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https://en.wikipedia.org/wiki/Diphenylchlorarsine
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Diphenylchloroarsine (DA) is the organoarsenic compound with the formula (C6H5)2AsCl. It is highly toxic and was once used in chemical warfare. It is also an intermediate in the preparation of other organoarsenic compounds. The molecule consists of a pyramidal As(III) center attached to two phenyl rings and one chloride. It was also known as sneezing oil during World War I by the Allies.
Preparation and structure
It was first produced in 1878 by the German chemists August Michaelis (1847–1916) and Wilhelm La Coste (1854–1885). It is prepared by the reduction of diphenylarsinic acid with sulfur dioxide. An idealized equation is shown:
Ph2AsO2H + SO2 + HCl → Ph2AsCl + H2SO4
The process adopted by Edgewood Arsenal, the "sodium process", for the production of DA for chemical warfare purposes employed a reaction between chlorobenzene and arsenic trichloride in the presence of sodium.
The German process, used in the first war, applied at Hochstam-Main, used the Sandmeyer reaction between phenyldiazonium chloride and sodium arsenite. The acidified product was reduced and then neutralized. The salt was condensed again by the Sandmeyer reaction and reduced again, the final product was then acidified, resulting in DA.
The structure consists of pyramidal As centre. The As-Cl distance is 2.26 A and the Cl-As-C and C-As-C angles are 96 and 105°, respectively.
Uses
It is a useful reagent for the preparation of other diphenylarsenic compounds, e.g. by reactions with Grignard reagents:
RMgBr + (C6H5)2AsCl → (C6H5)2AsR + MgBrCl
(R = alkyl, aryl)
Chemical warfare
Diphenylchlorarsine was used as a chemical weapon on the Western front during the trench warfare of World War I. It belongs to the class of chemicals classified as vomiting agents. Other such agents are diphenylcyanoarsine (DC) and diphenylaminechlorarsine (DM, Adamsite). Diphenylchlorarsine was sometimes believed to penetrate the gas masks of the time and to cause violent sneezing, forcing removal of the protecting dev
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https://en.wikipedia.org/wiki/Two-point%20tensor
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Two-point tensors, or double vectors, are tensor-like quantities which transform as Euclidean vectors with respect to each of their indices. They are used in continuum mechanics to transform between reference ("material") and present ("configuration") coordinates. Examples include the deformation gradient and the first Piola–Kirchhoff stress tensor.
As with many applications of tensors, Einstein summation notation is frequently used. To clarify this notation, capital indices are often used to indicate reference coordinates and lowercase for present coordinates. Thus, a two-point tensor will have one capital and one lower-case index; for example, AjM.
Continuum mechanics
A conventional tensor can be viewed as a transformation of vectors in one coordinate system to other vectors in the same coordinate system. In contrast, a two-point tensor transforms vectors from one coordinate system to another. That is, a conventional tensor,
,
actively transforms a vector u to a vector v such that
where v and u are measured in the same space and their coordinates representation is with respect to the same basis (denoted by the "e").
In contrast, a two-point tensor, G will be written as
and will transform a vector, U, in E system to a vector, v, in the e system as
.
The transformation law for two-point tensor
Suppose we have two coordinate systems one primed and another unprimed and a vectors' components transform between them as
.
For tensors suppose we then have
.
A tensor in the system . In another system, let the same tensor be given by
.
We can say
.
Then
is the routine tensor transformation. But a two-point tensor between these systems is just
which transforms as
.
Simple example
The most mundane example of a two-point tensor is the transformation tensor, the Q in the above discussion. Note that
.
Now, writing out in full,
and also
.
This then requires Q to be of the form
.
By definition of tensor product,
So we can write
Thus
Incorporating (),
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https://en.wikipedia.org/wiki/Cauchy%20stress%20tensor
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In continuum mechanics, the Cauchy stress tensor (symbol , named after Augustin-Louis Cauchy), also called true stress tensor or simply stress tensor, completely defines the state of stress at a point inside a material in the deformed state, placement, or configuration. The second order tensor consists of nine components and relates a unit-length direction vector e to the traction vector T(e) across an imaginary surface perpendicular to e:
The SI base units of both stress tensor and traction vector are newton per square metre (N/m2) or pascal (Pa), corresponding to the stress scalar. The unit vector is dimensionless.
The Cauchy stress tensor obeys the tensor transformation law under a change in the system of coordinates. A graphical representation of this transformation law is the Mohr's circle for stress.
The Cauchy stress tensor is used for stress analysis of material bodies experiencing small deformations: it is a central concept in the linear theory of elasticity. For large deformations, also called finite deformations, other measures of stress are required, such as the Piola–Kirchhoff stress tensor, the Biot stress tensor, and the Kirchhoff stress tensor.
According to the principle of conservation of linear momentum, if the continuum body is in static equilibrium it can be demonstrated that the components of the Cauchy stress tensor in every material point in the body satisfy the equilibrium equations (Cauchy's equations of motion for zero acceleration). At the same time, according to the principle of conservation of angular momentum, equilibrium requires that the summation of moments with respect to an arbitrary point is zero, which leads to the conclusion that the stress tensor is symmetric, thus having only six independent stress components, instead of the original nine. However, in the presence of couple-stresses, i.e. moments per unit volume, the stress tensor is non-symmetric. This also is the case when the Knudsen number is close to one, , or the co
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https://en.wikipedia.org/wiki/Board%20support%20package
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In embedded systems, a board support package (BSP) is the layer of software containing hardware-specific boot firmware and device drivers and other routines that allow a given embedded operating system, for example a real-time operating system (RTOS), to function in a given hardware environment (a motherboard), integrated with the embedded operating system.
Software
Third-party hardware developers who wish to support a given embedded operating system must create a BSP that allows that embedded operating system to run on their platform. In most cases, the embedded operating system image and software license, the BSP containing it, and the hardware are bundled together by the hardware vendor.
BSPs are typically customizable, allowing the user to specify which drivers and routines should be included in the build based on their selection of hardware and software options. For instance, a particular single-board computer might be paired with several peripheral chips; in that case the BSP might include drivers for peripheral chips supported; when building the BSP image the user would specify which peripheral drivers to include based on their choice of hardware.
Some suppliers also provide a root file system, a toolchain for building programs to run on the embedded system, and utilities to configure the device (while running) along with the BSP. Many embedded operating system providers provide template BSP's, developer assistance, and test suites to aid BSP developers to set up an embedded operating system on a new hardware platform.
History
The term BSP has been in use since 1981 when Hunter & Ready, the developers of the Versatile Real-Time Executive (VRTX), first coined the term to describe the hardware-dependent software needed to run VRTX on a specific hardware platform. Since the 1980s, it has been in wide use throughout the industry. Virtually all RTOS providers now use the term BSP.
Example
The Wind River Systems board support package for the ARM Integrator 92
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https://en.wikipedia.org/wiki/Entropy%20in%20thermodynamics%20and%20information%20theory
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The mathematical expressions for thermodynamic entropy in the statistical thermodynamics formulation established by Ludwig Boltzmann and J. Willard Gibbs in the 1870s are similar to the information entropy by Claude Shannon and Ralph Hartley, developed in the 1940s.
Equivalence of form of the defining expressions
The defining expression for entropy in the theory of statistical mechanics established by Ludwig Boltzmann and J. Willard Gibbs in the 1870s, is of the form:
where is the probability of the microstate i taken from an equilibrium ensemble, and is the Boltzmann's constant.
The defining expression for entropy in the theory of information established by Claude E. Shannon in 1948 is of the form:
where is the probability of the message taken from the message space M, and b is the base of the logarithm used. Common values of b are 2, Euler's number , and 10, and the unit of entropy is shannon (or bit) for b = 2, nat for b = , and hartley for b = 10.
Mathematically H may also be seen as an average information, taken over the message space, because when a certain message occurs with probability pi, the information quantity −log(pi) (called information content or self-information) will be obtained.
If all the microstates are equiprobable (a microcanonical ensemble), the statistical thermodynamic entropy reduces to the form, as given by Boltzmann,
where W is the number of microstates that corresponds to the macroscopic thermodynamic state. Therefore S depends on temperature.
If all the messages are equiprobable, the information entropy reduces to the Hartley entropy
where is the cardinality of the message space M.
The logarithm in the thermodynamic definition is the natural logarithm. It can be shown that the Gibbs entropy formula, with the natural logarithm, reproduces all of the properties of the macroscopic classical thermodynamics of Rudolf Clausius. (See article: Entropy (statistical views)).
The logarithm can also be taken to the natural base
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https://en.wikipedia.org/wiki/Winterbottom%27s%20sign
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Winterbottom's sign is a swelling of lymph nodes (lymphadenopathy) along the posterior cervical lymph node chain, associated with the early phase of African trypanosomiasis (African sleeping sickness), a disease caused by the parasites Trypanosoma brucei rhodesiense and Trypanosoma brucei gambiense. It may be suggestive of cerebral infection. Winterbottom reported about the slave traders who, apparently aware of the ominous sign of swollen cervical lymph glands, used to palpate the necks of the slaves before buying them.
The sign was first reported by the English physician Thomas Masterman Winterbottom in 1803.
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https://en.wikipedia.org/wiki/Teaching%20dimension
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In computational learning theory, the teaching dimension of a concept class C is defined to be , where is the minimum size of a witness set for c in C. Intuitively, this measures the number of instances that are needed to identify a concept in the class, using supervised learning with examples provided by a helpful teacher who is trying to convey the concept as succinctly as possible. This definition was formulated in 1995 by Sally Goldman and Michael Kearns, based on earlier work by Goldman, Ron Rivest, and Robert Schapire.
The teaching dimension of a finite concept class can be used to give a lower and an upper bound on the membership query cost of the concept class.
In Stasys Jukna's book "Extremal Combinatorics", a lower bound is given for the teaching dimension in general:
Let C be a concept class over a finite domain X. If the size of C is greater than
then the teaching dimension of C is greater than k.
However, there are more specific teaching models that make assumptions about teacher or learner, and can get lower values for the teaching dimension. For instance, several models are the classical teaching (CT) model, the optimal teacher (OT) model, recursive teaching (RT), preference-based teaching (PBT), and non-clashing teaching (NCT).
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https://en.wikipedia.org/wiki/Witness%20set
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In computational learning theory, let C be a concept class over a domain X and c be a concept in C. A subset S of X is a witness set for c in C if c(S) verifies c (i.e., c is the only consistent concept with respect to c(S)). The minimum size of a witness set for c is called the witness size or specification number and is denoted by . The value is called the teaching dimension of C.
Computational learning theory
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https://en.wikipedia.org/wiki/Concept%20class
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In computational learning theory in mathematics, a concept over a domain X is a total Boolean function over X. A concept class is a class of concepts. Concept classes are a subject of computational learning theory.
Concept class terminology frequently appears in model theory associated with probably approximately correct (PAC) learning. In this setting, if one takes a set Y as a set of (classifier output) labels, and X is a set of examples, the map , i.e. from examples to classifier labels (where and where c is a subset of X), c is then said to be a concept. A concept class is then a collection of such concepts.
Given a class of concepts C, a subclass D is reachable if there exists a sample s such that D contains exactly those concepts in C that are extensions to s. Not every subclass is reachable.
Background
A sample is a partial function from to . Identifying a concept with its characteristic function mapping to , it is a special case of a sample.
Two samples are consistent if they agree on the intersection of their domains. A sample extends another sample if the two are consistent and the domain of is contained in the domain of .
Examples
Suppose that . Then:
the subclass is reachable with the sample ;
the subclass for are reachable with a sample that maps the elements of to zero;
the subclass , which consists of the singleton sets, is not reachable.
Applications
Let be some concept class. For any concept , we call this concept -good for a positive integer if, for all , at least of the concepts in agree with on the classification of . The fingerprint dimension of the entire concept class is the least positive integer such that every reachable subclass contains a concept that is -good for it. This quantity can be used to bound the minimum number of equivalence queries needed to learn a class of concepts according to the following inequality:.
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https://en.wikipedia.org/wiki/Bondy%27s%20theorem
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In mathematics, Bondy's theorem is a bound on the number of elements needed to distinguish the sets in a family of sets from each other. It belongs to the field of combinatorics, and is named after John Adrian Bondy, who published it in 1972.
Statement
The theorem is as follows:
Let X be a set with n elements and let A1, A2, ..., An be distinct subsets of X. Then there exists a subset S of X with n − 1 elements such that the sets Ai ∩ S are all distinct.
In other words, if we have a 0-1 matrix with n rows and n columns such that each row is distinct, we can remove one column such that the rows of the resulting n × (n − 1) matrix are distinct.
Example
Consider the 4 × 4 matrix
where all rows are pairwise distinct. If we delete, for example, the first column, the resulting matrix
no longer has this property: the first row is identical to the second row. Nevertheless, by Bondy's theorem we know that we can always find a column that can be deleted without introducing any identical rows. In this case, we can delete the third column: all rows of the 3 × 4 matrix
are distinct. Another possibility would have been deleting the fourth column.
Learning theory application
From the perspective of computational learning theory, Bondy's theorem can be rephrased as follows:
Let C be a concept class over a finite domain X. Then there exists a subset S of X with the size at most |C| − 1 such that S is a witness set for every concept in C.
This implies that every finite concept class C has its teaching dimension bounded by |C| − 1.
Notes
Computational learning theory
Theorems in combinatorics
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https://en.wikipedia.org/wiki/Cartesian%20materialism
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In philosophy of mind, Cartesian materialism is the idea that at some place (or places) in the brain, there is some set of information that directly corresponds to our conscious experience. Contrary to its name, Cartesian materialism is not a view that was held by or formulated by René Descartes, who subscribed rather to a form of substance dualism.
In its simplest version, Cartesian materialism might predict, for example, that there is a specific place in the brain which would be a coherent representation of everything we are consciously experiencing in a given moment: what we're seeing, what we're hearing, what we're smelling, and indeed, everything of which we are consciously aware. In essence, Cartesian materialism claims that, somewhere in our brain, there is a Cartesian theater where a hypothetical observer could somehow "find" the content of conscious experience moment by moment. In contrast, anything occurring outside of this "privileged neural media" is nonconscious.
History
Multiple meanings
French materialism developed from the mechanism of Descartes and the empiricism of Locke, Hobbes, Bacon and ultimately Duns Scotus who asked "Whether matter could not think?" Natural science, in their view, owes to the former its great success as a "Cartesian materialism", bereft of the metaphysics of Cartesian dualism by philosophers and physicians such as Regius, Cabanis, and La Mettrie, who maintained the viability of Descartes' biological automata without recourse to immaterial cognition.
However, philosopher Daniel Dennett uses the term to emphasize what he considers the pervasive Cartesian notion of a centralized repository of conscious experience in the brain. Dennett says that "Cartesian materialism is the view that there is a crucial finish line or boundary somewhere in the brain, marking a place where the order of arrival equals the order of 'presentation' in experience because what happens there is what you are conscious of."
Other modern philosophers
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https://en.wikipedia.org/wiki/SCSI%20command
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In SCSI computer storage, computers and storage devices use a client-server model of communication. The computer is a client which requests the storage device to perform a service, e.g., to read or write data. The SCSI command architecture was originally defined for parallel SCSI buses but has been carried forward with minimal change for use with Fibre Channel, iSCSI, Serial Attached SCSI, and other transport layers.
In the SCSI protocol, the initiator sends a SCSI command information unit to the target device. Data information units may then be transferred between the computer and device. Finally, the device sends a response information unit to the computer.
SCSI commands are sent in a command descriptor block (CDB), which consists of a one byte operation code (opcode) followed by five or more bytes containing command-specific parameters. Upon receiving and processing the CDB the device will return a status code byte and other information.
The rest of this article contains a list of SCSI commands, sortable in opcode or description alphabetical order. In the published SCSI standards, commands are designated as "mandatory," "optional" or "vendor-unique." Only the mandatory commands are required of all devices. There are links to detailed descriptions for the more common SCSI commands. Some opcodes produce different, though usually comparable, effects in different device types; for example, opcode recalibrates a disk drive by seeking back to physical sector zero, but rewinds the medium in a tape drive.
SCSI command lengths
Originally the most significant 3 bits of a SCSI opcode specified the length of the CDB. However, when variable-length CDBs were created this correspondence was changed, and the entire opcode must be examined to determine the CDB length.
The lengths are as follows:
List of SCSI commands
When a command is defined in multiple CDB sizes, the length of the CDB is given in parentheses after the command name, e.g., READ(6) and READ(10).
E
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https://en.wikipedia.org/wiki/Invariant%20basis%20number
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In mathematics, more specifically in the field of ring theory, a ring has the invariant basis number (IBN) property if all finitely generated free left modules over R have a well-defined rank. In the case of fields, the IBN property becomes the statement that finite-dimensional vector spaces have a unique dimension.
Definition
A ring R has invariant basis number (IBN) if for all positive integers m and n, Rm isomorphic to Rn (as left R-modules) implies that .
Equivalently, this means there do not exist distinct positive integers m and n such that Rm is isomorphic to Rn.
Rephrasing the definition of invariant basis number in terms of matrices, it says that, whenever A is an m-by-n matrix over R and B is an n-by-m matrix over R such that and , then . This form reveals that the definition is left–right symmetric, so it makes no difference whether we define IBN in terms of left or right modules; the two definitions are equivalent.
Note that the isomorphisms in the definitions are not ring isomorphisms, they are module isomorphisms, even when one of n or m is 1.
Properties
The main purpose of the invariant basis number condition is that free modules over an IBN ring satisfy an analogue of the dimension theorem for vector spaces: any two bases for a free module over an IBN ring have the same cardinality. Assuming the ultrafilter lemma (a strictly weaker form of the axiom of choice), this result is actually equivalent to the definition given here, and can be taken as an alternative definition.
The rank of a free module Rn over an IBN ring R is defined to be the cardinality of the exponent m of any (and therefore every) R-module Rm isomorphic to Rn. Thus the IBN property asserts that every isomorphism class of free R-modules has a unique rank. The rank is not defined for rings not satisfying IBN. For vector spaces, the rank is also called the dimension. Thus the result above is in short: the rank is uniquely defined for all free R-modules iff it is uniquely def
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https://en.wikipedia.org/wiki/GPFS
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GPFS (General Parallel File System, brand name IBM Storage Scale and previously IBM Spectrum Scale) is high-performance clustered file system software developed by IBM. It can be deployed in shared-disk or shared-nothing distributed parallel modes, or a combination of these. It is used by many of the world's largest commercial companies, as well as some of the supercomputers on the Top 500 List.
For example, it is the filesystem of the Summit
at Oak Ridge National Laboratory which was the #1 fastest supercomputer in the world in the November 2019 TOP500 list of supercomputers. Summit is a 200 Petaflops system composed of more than 9,000 POWER9 processors and 27,000 NVIDIA Volta GPUs. The storage filesystem called Alpine has 250 PB of storage using Spectrum Scale on IBM ESS storage hardware, capable of approximately 2.5TB/s of sequential I/O and 2.2TB/s of random I/O.
Like typical cluster filesystems, GPFS provides concurrent high-speed file access to applications executing on multiple nodes of clusters. It can be used with AIX clusters, Linux clusters, on Microsoft Windows Server, or a heterogeneous cluster of AIX, Linux and Windows nodes running on x86, Power or IBM Z processor architectures. In addition to providing filesystem storage capabilities, it provides tools for management and administration of the GPFS cluster and allows for shared access to file systems from remote clusters.
History
GPFS began as the Tiger Shark file system, a research project at IBM's Almaden Research Center as early as 1993. Tiger Shark was initially designed to support high throughput multimedia applications. This design turned out to be well suited to scientific computing.
Another ancestor is IBM's Vesta filesystem, developed as a research project at IBM's Thomas J. Watson Research Center between 1992 and 1995. Vesta introduced the concept of file partitioning to accommodate the needs of parallel applications that run on high-performance multicomputers with parallel I/O subsystem
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https://en.wikipedia.org/wiki/List%20of%20national%20flowers
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In a number of countries, plants have been chosen as symbols to represent specific geographic areas. Some countries have a country-wide floral emblem; others in addition have symbols representing subdivisions. Different processes have been used to adopt these symbols – some are conferred by government bodies, whereas others are the result of informal public polls. The term floral emblem, which refers to flowers specifically, is primarily used in Australia and Canada. In the United States, the term state flower is more often used.
National plants
Africa
Mauritius
The national flower of Mauritius is Ruizia boutoniana.
Nigeria
The national flower of Nigeria is Costus spectabilis which is commonly known as Yellow Trumpet.
Seychelles
The national flower of the Seychelles is the tropicbird orchid (known locally as orkid payanke), Angraecum eburneum.
South Africa
The national flower of South Africa is the King Protea, Protea cynaroides.
Tunisia
The national flower of Tunisia is jasmine. It was chosen as a symbol for the 2010 Tunisian Revolution.
Asia
Bangladesh
The national flower of Bangladesh is the water lily Nymphaea nouchali. It is called Shapla (শাপলা) in the Bengali language.
Bhutan
The national flower of Bhutan is the blue poppy. Previously misidentified as the non-native Meconopsis grandis, national flower of Bhutan was identified in 2017 as Meconopsis gakyidiana, a new distinct species.
Brunei
The national flower of Brunei is Simpoh Ayer (Dillenia suffruticosa).
Cambodia
Cambodia formally adopted the romduol () as its national flower in the year 2005 by a royal decree. The royal decree designates the taxon as Mitrella mesnyi, however, this is a taxonomically illegitimate synonym for Sphaerocoryne affinis.
Hong Kong
The symbolic flower of Hong Kong is the Hong Kong orchid tree ("洋紫荊"), Bauhinia blakeana.
India
The national flower of India is the lotus flower (Nelumbo nucifera). It is a sacred flower and occupies a unique position in the art and
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https://en.wikipedia.org/wiki/Watchful%20waiting
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Watchful waiting (also watch and wait or WAW) is an approach to a medical problem in which time is allowed to pass before medical intervention or therapy is used. During this time, repeated testing may be performed.
Related terms include expectant management, active surveillance, and masterly inactivity. The term masterly inactivity is also used in nonmedical contexts.
A distinction can be drawn between watchful waiting and medical observation, but some sources equate the terms. Usually, watchful waiting is an outpatient process and may have a duration of months or years. In contrast, medical observation is usually an inpatient process, often involving frequent or even continuous monitoring and may have a duration of hours or days.
Medical uses
Often watchful waiting is recommended in situations with a high likelihood of self-resolution if there is high uncertainty concerning the diagnosis, and the risks of intervention or therapy may outweigh the benefits.
Watchful waiting is often recommended for many common illnesses such as ear infections in children; because the majority of cases resolve spontaneously, antibiotics will often be prescribed only after several days of symptoms. It is also a strategy frequently used in surgery prior to a possible operation, when it is possible for a symptom (for example abdominal pain) to either improve naturally or become worse.
Other examples include:
the diagnosis and treatment of benign prostatic hyperplasia
depression
otitis media
inguinal hernia
odd behaviors in infants
Active surveillance of prostate cancer
non-symptomatic kidney stones
Process
Watchful waiting
In many applications, a key component of watchful waiting is the use of an explicit decision tree or other protocol to ensure a timely transition from watchful waiting to another form of management, as needed. This is particularly common in the post-surgical management of cancer survivors, in whom cancer recurrence is a significant concern.
Medical ob
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https://en.wikipedia.org/wiki/Higher-order%20differential%20cryptanalysis
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In cryptography, higher-order differential cryptanalysis is a generalization of differential cryptanalysis, an attack used against block ciphers. While in standard differential cryptanalysis the difference between only two texts is used, higher-order differential cryptanalysis studies the propagation of a set of differences between a larger set of texts. Xuejia Lai, in 1994, laid the groundwork by showing that differentials are a special case of the more general case of higher order derivates. Lars Knudsen, in the same year, was able to show how the concept of higher order derivatives can be used to mount attacks on block ciphers. These attacks can be superior to standard differential cryptanalysis. Higher-order differential cryptanalysis has notably been used to break the KN-Cipher, a cipher which had previously been proved to be immune against standard differential cryptanalysis.
Higher-order derivatives
A block cipher which maps -bit strings to -bit strings can, for a fixed key, be thought of as a function . In standard differential cryptanalysis, one is interested in finding a pair of an input difference and an output difference such that two input texts with difference are likely to result in output texts with a difference i.e., that is true for many . Note that the difference used here is the XOR which is the usual case, though other definitions of difference are possible.
This motivates defining the derivative of a function at a point as
Using this definition, the -th derivative at can recursively be defined as
Thus for example .
Higher order derivatives as defined here have many properties in common with ordinary derivative such as the sum rule and the product rule. Importantly also, taking the derivative reduces the algebraic degree of the function.
Higher-order differential attacks
To implement an attack using higher order derivatives, knowledge about the probability distribution of the derivative of the cipher is needed. Calculating or est
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https://en.wikipedia.org/wiki/Impossible%20differential%20cryptanalysis
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In cryptography, impossible differential cryptanalysis is a form of differential cryptanalysis for block ciphers. While ordinary differential cryptanalysis tracks differences that propagate through the cipher with greater than expected probability, impossible differential cryptanalysis exploits differences that are impossible (having probability 0) at some intermediate state of the cipher algorithm.
Lars Knudsen appears to be the first to use a form of this attack, in the 1998 paper where he introduced his AES candidate, DEAL. The first presentation to attract the attention of the cryptographic community was later the same year at the rump session of CRYPTO '98, in which Eli Biham, Alex Biryukov, and Adi Shamir introduced the name "impossible differential" and used the technique to break 4.5 out of 8.5 rounds of IDEA and 31 out of 32 rounds of the NSA-designed cipher Skipjack. This development led cryptographer Bruce Schneier to speculate that the NSA had no previous knowledge of impossible differential cryptanalysis. The technique has since been applied to many other ciphers: Khufu and Khafre, E2, variants of Serpent, MARS, Twofish, Rijndael (AES), CRYPTON, Zodiac, Hierocrypt-3, TEA, XTEA, Mini-AES, ARIA, Camellia, and SHACAL-2.
Biham, Biryukov and Shamir also presented a relatively efficient specialized method for finding impossible differentials that they called a miss-in-the-middle attack. This consists of finding "two events with probability one, whose conditions cannot be met together."
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https://en.wikipedia.org/wiki/Terry%20Collection
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The Robert J. Terry Anatomical Skeletal Collection is a collection of some 1,728 human skeletons held by the Department of Anthropology of the National Museum of Natural History of the Smithsonian Institution, Washington, D.C., United States.
Background
It was created by Robert J. Terry (1871–1966) during his time as professor of anatomy and head of the Anatomy Department at Washington University Medical School in St. Louis, Missouri from 1899 until his retirement in 1941. It was transferred to its present holders in 1967. The Terry Collection is composed of skeletons that Terry collected from the Medical School's Gross Anatomy classes during his tenure at Washington University. The majority of the remains that make up the collection came from local hospitals in the St. Louis area, as well as institutional morgues. The remains obtained from these hospitals and institutions were those of individuals who had not been claimed by relatives, effectively making the remains the property of the state. The state of Missouri decided to donate the bodies to the medical school rather than spend taxpayer money to bury them.
The collection is an important source for anthropological research because of the extensive documentation that accompanies each skeleton. Terry attempted to collect data such as morgue records, dental charts, bone inventory forms, and anthropometric and anthroposcopic forms for the majority of the skeletons in the collection. Although methods of data collection changed over the years that the collection was being amassed, the same basic information was consistently collected. This information includes name, sex, age, race, cause of death, date of death, morgue or institution of origin, permit number, and various dates and records that pertain to embalming and processing of the cadaver. Terry also collected other resources for some of the individuals in the collection such as photographs or photo negatives of cadavers, plaster death masks, hair samples, an
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https://en.wikipedia.org/wiki/Interpolation%20attack
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In cryptography, an interpolation attack is a type of cryptanalytic attack against block ciphers.
After the two attacks, differential cryptanalysis and linear cryptanalysis, were presented on block ciphers, some new block ciphers were introduced, which were proven secure against differential and linear attacks. Among these there were some iterated block ciphers such as the KN-Cipher and the SHARK cipher. However, Thomas Jakobsen and Lars Knudsen showed in the late 1990s that these ciphers were easy to break by introducing a new attack called the interpolation attack.
In the attack, an algebraic function is used to represent an S-box. This may be a simple quadratic, or a polynomial or rational function over a Galois field. Its coefficients can be determined by standard Lagrange interpolation techniques, using known plaintexts as data points. Alternatively, chosen plaintexts can be used to simplify the equations and optimize the attack.
In its simplest version an interpolation attack expresses the ciphertext as a polynomial of the plaintext. If the polynomial has a relative low number of unknown coefficients, then with a collection of plaintext/ciphertext (p/c) pairs, the polynomial can be reconstructed. With the polynomial reconstructed the attacker then has a representation of the encryption, without exact knowledge of the secret key.
The interpolation attack can also be used to recover the secret key.
It is easiest to describe the method with an example.
Example
Let an iterated cipher be given by
where is the plaintext, the output of the round, the secret round key (derived from the secret key by some key schedule), and for a -round iterated cipher, is the ciphertext.
Consider the 2-round cipher. Let denote the message, and denote the ciphertext.
Then the output of round 1 becomes
and the output of round 2 becomes
Expressing the ciphertext as a polynomial of the plaintext yields
where the 's are key dependent constants.
Using as many plainte
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https://en.wikipedia.org/wiki/Waterleaf%20%28architecture%29
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In architecture, a waterleaf is a distinctive sculptural motif used on the capitals of columns and pilasters in European buildings during the late twelfth century. It is a highly simplified plant motif, characteristic of the "late Norman" style of Romanesque architecture.
A waterleaf capital is formed of broad, smooth leaf-shapes (typically four in number), unribbed except for a central fold, which curve upward and outward before curling over at the tips where they meet the abacus (the flat slab at the top of the column, normally square but sometimes octagonal). The curled tip of the waterleaf may be small and neat or large and bulbous; it usually curves inward towards the abacus, but may occasionally turn outwards (both forms can sometimes be seen in adjacent capitals of the same period, as for example at Geddington, Northamptonshire, UK.).
Gallery
See also
Abacus (architecture)
Branchwork
Pulvino
Rais-de-cœur may incorporate waterleaves.
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https://en.wikipedia.org/wiki/Opt-in%20email
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Opt-in email is a term used when someone is not initially added to an emailing list and is instead given the option to join the emailing list. Typically, this is some sort of mailing list, newsletter, or advertising. Opt-out emails do not ask for permission to send emails, these emails are typically criticized as unsolicited bulk emails, better known as spam.
Forms
There are several common forms of opt-in email:
Unconfirmed opt-in/single opt-in
Someone first gives an email address to the list software (for instance, on a Web page), but no steps are taken to make sure that this address belongs to the person submitting it. This can cause email from the mailing list to be considered spam because simple typos of the email address can cause the email to be sent to someone else. Malicious subscriptions are also possible, as are subscriptions that are due to spammers forging email addresses that are sent to the email address used to subscribe to the mailing list.
Confirmed opt-in (COI)/double opt-in (DOI)
A new subscriber asks to be subscribed to the mailing list, but unlike unconfirmed or single opt-in, a confirmation email is sent to verify it was really them. Generally, unless the explicit step is taken to verify the end-subscriber's e-mail address, such as clicking a special web link or sending back a reply email, it is difficult to establish that the e-mail address in question indeed belongs to the person who submitted the request to receive the e-mail. Using a confirmed opt-in (COI) (also known as a Double opt-in) procedure helps to ensure that a third party is not able to subscribe someone else accidentally, or out of malice, since if no action is taken on the part of the e-mail recipient, they will simply no longer receive any messages from the list operator. Mail system administrators and non-spam mailing list operators refer to this as confirmed subscription or closed-loop opt-in.
Some marketers call closed-loop opt-in "double opt-in". This term was
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https://en.wikipedia.org/wiki/Anthrax%20vaccine
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Anthrax vaccines are vaccines to prevent the livestock and human disease anthrax, caused by the bacterium Bacillus anthracis.
They have had a prominent place in the history of medicine, from Pasteur's pioneering 19th-century work with cattle (the first effective bacterial vaccine and the second effective vaccine ever) to the controversial late 20th century use of a modern product to protect American troops against the use of anthrax in biological warfare. Human anthrax vaccines were developed by the Soviet Union in the late 1930s and in the US and UK in the 1950s. The current vaccine approved by the U.S. Food and Drug Administration (FDA) was formulated in the 1960s.
Currently administered human anthrax vaccines include acellular (USA, UK) and live spore (Russia) varieties. All currently used anthrax vaccines show considerable local and general reactogenicity (erythema, induration, soreness, fever) and serious adverse reactions occur in about 1% of recipients. New third-generation vaccines being researched include recombinant live vaccines and recombinant sub-unit vaccines.
Pasteur's vaccine
In the 1870s, the French chemist Louis Pasteur (1822–1895) applied his previous method of immunising chickens against chicken cholera to anthrax, which affected cattle, and thereby aroused widespread interest in combating other diseases with the same approach. In May 1881, Pasteur performed a famous public experiment at Pouilly-le-Fort to demonstrate his concept of vaccination. He prepared two groups of 25 sheep, one goat and several cows. The animals of one group were twice injected, with an interval of 15 days, with an anthrax vaccine prepared by Pasteur; a control group was left unvaccinated. Thirty days after the first injection, both groups were injected with a culture of live anthrax bacteria. All the animals in the non-vaccinated group died, while all of the animals in the vaccinated group survived. The public reception was sensational.
Pasteur publicly claimed he h
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https://en.wikipedia.org/wiki/Cryptocurrency%20exchange
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A cryptocurrency exchange, or a digital currency exchange (DCE), is a business that allows customers to trade cryptocurrencies or digital currencies for other assets, such as conventional fiat money or other digital currencies. Exchanges may accept credit card payments, wire transfers or other forms of payment in exchange for digital currencies or cryptocurrencies. A cryptocurrency exchange can be a market maker that typically takes the bid–ask spreads as a transaction commission for its service or, as a matching platform, simply charges fees.
Some brokerages which also focus on other assets such as stocks, like Robinhood and eToro, let users purchase but not withdraw cryptocurrencies to cryptocurrency wallets. Dedicated cryptocurrency exchanges such as Binance and Coinbase do allow cryptocurrency withdrawals, however.
Operation
A cryptocurrency exchange can typically send cryptocurrency to a user's personal cryptocurrency wallet. Some can convert digital currency balances into anonymous prepaid cards which can be used to withdraw funds from ATMs worldwide while other digital currencies are backed by real-world commodities such as gold.
The creators of digital currencies are typically independent of the digital currency exchange that facilitate trading in the currency. In one type of system, digital currency providers (DCP) are businesses that keep and administer accounts for their customers, but generally do not issue digital currency to those customers directly. Customers buy or sell digital currency from digital currency exchanges, who transfer the digital currency into or out of the customer's DCP account. Some exchanges are subsidiaries of DCP, but many are legally independent businesses. The denomination of funds kept in DCP accounts may be of a real or fictitious currency.
A digital currency exchange can be a brick-and-mortar business or a strictly online business. As a brick-and-mortar business, it exchanges traditional payment methods and digital curr
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https://en.wikipedia.org/wiki/Debye%E2%80%93Waller%20factor
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The Debye–Waller factor (DWF), named after Peter Debye and Ivar Waller, is used in condensed matter physics to describe the attenuation of x-ray scattering or coherent neutron scattering caused by thermal motion. It is also called the B factor, atomic B factor, or temperature factor. Often, "Debye–Waller factor" is used as a generic term that comprises the Lamb–Mössbauer factor of incoherent neutron scattering and Mössbauer spectroscopy.
The DWF depends on the scattering vector q. For a given q, DWF(q) gives the fraction of elastic scattering; 1 – DWF(q) correspondingly gives the fraction of inelastic scattering (strictly speaking, this probability interpretation is not true in general). In diffraction studies, only the elastic scattering is useful; in crystals, it gives rise to distinct Bragg reflection peaks. Inelastic scattering events are undesirable as they cause a diffuse background — unless the energies of scattered particles are analysed, in which case they carry valuable information (for instance in inelastic neutron scattering or electron energy loss spectroscopy).
The basic expression for the DWF is given by
where u is the displacement of a scattering center,
and denotes either thermal or time averaging.
Assuming harmonicity of the scattering centers in the material under study, the Boltzmann distribution implies that is normally distributed with zero mean. Then, using for example the expression of the corresponding characteristic function, the DWF takes the form
Note that although the above reasoning is classical, the same holds in quantum mechanics.
Assuming also isotropy of the harmonic potential, one may write
where q, u are the magnitudes (or absolute values) of the vectors q, u respectively, and is the mean squared displacement. In crystallographic publications, values of are often given where . Note that if the incident wave has wavelength , and it is elastically scattered by an angle of , then
In the context of protein structures, th
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https://en.wikipedia.org/wiki/Odell%20Lake%20%28video%20game%29
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Odell Lake is a 1986 educational life simulation game produced by MECC for the Apple II and Commodore 64. The player is a fish living in Odell Lake, a real-world lake in Oregon. It is based on a 1980 BASIC program of the same name. It was followed-up by Odell Down Under.
Gameplay
As a fish, the player could "go exploring" or "play for points". The object was to decide which fish to eat, while trying to survive and avoid other enemies; such as otters, ospreys, and bait from fishermen. When simply exploring, the player could select from six different species of fish, such as Mackinaw Trout, Whitefish, or Rainbow Trout; however, when playing for points, the computer randomly assigned the type of fish that the player will play as. In addition, the titles for each of the types of fish and other creatures are removed when playing for points, forcing the player to rely on memory; also the game was timed. After every five moves, the player played as a different type of fish.
When playing for points, the best decision netted the player the most points, with less intelligent decisions earning the player fewer or no points, or in the case of the fish eating something disagreeable, actually taking them away. If no decision was made when time ran out, it counted as "Ignore". If at any time the player's fish was attacked by an enemy, or the player got caught by an angler, the game ended immediately.
In Israel the game was published in Hebrew in 1987 for Apple II.
Main fish
The species of fish found in Odell Lake included the following:
Rainbow trout
Dolly Varden trout
Mackinaw trout, the largest fish in the game
Blueback salmon
Whitefish
Chub, the smallest fish in the game
The game is heavily random; the same situation played in the same way can have different outcomes. For the most points, players must play the game safely, choosing the action that has the greatest chance of leading to a positive outcome. It's helpful to remember the typical locations of food and predator
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https://en.wikipedia.org/wiki/Service%20Profile%20Identifier
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A Service Profile Identifier (SPID) is a number issued by ISDN service providers in North America that identifies the services and features of an ISDN circuit. Service providers typically assign each B channel a unique SPID. A SPID is derived from the telephone number assigned to the circuit, and in the U.S. it typically follows a generic, 14-digit format.
A SPID (Service Profile Identifier) is a number assigned by a phone company to a terminal on an Integrated Services Digital Network B-channel. A SPID tells equipment at the phone company's central office about the capabilities of each terminal (computer or phone) on the B-channels. A Basic Rate home or business user may divide service into two B-channels with one used for normal phone service and the other for computer data. The SPID tells the phone company whether the terminal accepts voice or data information.
The SPID is a numeric string from 3 to 20 digits in length. A SPID (or more than one, if necessary) is assigned when the ISDN Basic Rate Interface (BRI) is obtained from the phone company. Starting in 1998, most phone companies began to use a generic SPID format. In this format, the SPID is a 14-digit number that includes a 10-digit telephone number (which includes the 3-digit Numbering Plan Area code), a 2-digit Sharing Terminal Identifier, and a 2-digit Terminal Identifier (TID). The generic SPID format makes it easier to tell users what to specify when installing an ISDN line and simplifies corporate installation procedures.
Back in 1998, some ISDN manufacturers began to provide non-initializing terminals (NITs) that do not require the entering of a SPID. Manufacturers also are delivering terminals with automated SPID selection in which the correct SPID is downloaded to the terminal rather than having to be specified by the user.
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https://en.wikipedia.org/wiki/Speech%20analytics
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Speech analytics is the process of analyzing recorded calls to gather customer information to improve communication and future interaction. The process is primarily used by customer contact centers to extract information buried in client interactions with an enterprise. Although speech analytics includes elements of automatic speech recognition, it is known for analyzing the topic being discussed, which is weighed against the emotional character of the speech and the amount and locations of speech versus non-speech during the interaction. Speech analytics in contact centers can be used to mine recorded customer interactions to surface the intelligence essential for building effective cost containment and customer service strategies. The technology can pinpoint cost drivers, trend analysis, identify strengths and weaknesses with processes and products, and help understand how the marketplace perceives offerings.
Definition
Speech analytics provides a Complete analysis of recorded phone conversations between a company and its customers. It provides advanced functionality and valuable intelligence from customer calls. This information can be used to discover information relating to strategy, product, process, operational issues and contact center agent performance. In addition, speech analytics can automatically identify areas in which contact center agents may need additional training or coaching, and can automatically monitor the customer service provided on calls.
The process can isolate the words and phrases used most frequently within a given time period, as well as indicate whether usage is trending up or down. This information is useful for supervisors, analysts, and others in an organization to spot changes in consumer behavior and take action to reduce call volumes—and increase customer satisfaction. It allows insight into a customer's thought process, which in turn creates an opportunity for companies to make adjustments.
Usability
Speech analytics applic
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https://en.wikipedia.org/wiki/Cadinenes
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Cadinenes are a group of isomeric hydrocarbons that occur in a wide variety of essential oil-producing plants. The name is derived from that of the Cade juniper (Juniperus oxycedrus L.), the wood of which yields an oil from which cadinene isomers were first isolated.
Chemically, the cadinenes are bicyclic sesquiterpenes. The term cadinene has sometimes also been used in a broad sense to refer to any sesquiterpene with the so-called cadalane (4-isopropyl-1,6-dimethyldecahydronaphthalene) carbon skeleton. Because of the large number of known double-bond and stereochemical isomers, this class of compounds has been subdivided into four subclasses based on the relative stereochemistry at the isopropyl group and the two bridgehead carbon atoms. The name cadinene is now properly used only for the first subclass below, which includes the compounds originally isolated from cade oil. Only one enantiomer of each subclass is depicted, with the understanding that the other enantiomer bears the same subclass name.
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https://en.wikipedia.org/wiki/Optical%20power
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In optics, optical power (also referred to as dioptric power, refractive power, focusing power, or convergence power) is the degree to which a lens, mirror, or other optical system converges or diverges light. It is equal to the reciprocal of the focal length of the device: . High optical power corresponds to short focal length. The SI unit for optical power is the inverse metre (m−1), which is commonly called the dioptre (symbol: dpt).
Converging lenses have positive optical power, while diverging lenses have negative power. When a lens is immersed in a refractive medium, its optical power and focal length change.
For two or more thin lenses close together, the optical power of the combined lenses is approximately equal to the sum of the optical powers of each lens: . Similarly, the optical power of a single lens is roughly equal to the sum of the powers of each surface. These approximations are commonly used in optometry.
An eye that has too much or too little refractive power to focus light onto the retina has a refractive error. A myopic eye has too much power so light is focused in front of the retina. This is noted as a minus power. Conversely, a hyperopic eye has too little power so when the eye is relaxed, light is focused behind the retina. An eye with a refractive power in one meridian that is different from the refractive power of the other meridians has astigmatism. This is also known as a cylindrical power. Anisometropia is the condition in which one eye has a different refractive power than the other eye.
See also
Accommodation of the eye
Lens clock
Lensmeter
Plate scale
Vergence
Vertometer
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https://en.wikipedia.org/wiki/Suction%20cup
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A suction cup, also known as a sucker, is a device or object that uses the negative fluid pressure of air or water to adhere to nonporous surfaces, creating a partial vacuum.
Suction cups are peripheral traits of some animals such as octopuses and squids, and have been reproduced artificially for numerous purposes.
Theory
The working face of the suction cup is made of elastic, flexible material and has a curved surface. When the center of the suction cup is pressed against a flat, non-porous surface, the volume of the space between the suction cup and the flat surface is reduced, which causes the air or water between the cup and the surface to be expelled past the rim of the circular cup. The cavity which develops between the cup and the flat surface has little to no air or water in it because most of the fluid has already been forced out of the inside of the cup, causing a lack of pressure. The pressure difference between the atmosphere on the outside of the cup and the low-pressure cavity on the inside of the cup keeps the cup adhered to the surface.
When the user ceases to apply physical pressure to the outside of the cup, the elastic substance of which the cup is made tends to resume its original, curved shape. The length of time for which the suction effect can be maintained depends mainly on how long it takes for air or water to leak back into the cavity between the cup and the surface, equalizing the pressure with the surrounding atmosphere. This depends on the porosity and flatness of the surface and the properties of the cup's rim. A small amount of mineral oil or vegetable oil is often employed to help maintain the seal.
Calculations
The force required to detach an ideal suction cup by pulling it directly away from the surface is given by the formula:
where:
F is the force,
A is the area of the surface covered by the cup,
P is the pressure outside the cup (typically atmospheric pressure)
This is derived from the definition of pressure, which is:
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https://en.wikipedia.org/wiki/Aj%C3%AD%20%28sauce%29
|
Ají is a spicy sauce that contains ají peppers, oil, tomatoes, cilantro (coriander), garlic, onions, and water. It is served as a condiment to complement main dishes, most oftentimes in Latin American cuisines, and prepared by blending its ingredients using a food processor or blender. Although ají sauce recipes can vary from person to person, there are generally country-specific and region-specific varieties.
Description
Ají is a spicy sauce made from ají peppers that is usually served to accompany other dishes in a variety of Latin American cuisines. Its most basic ingredients include ají peppers, water, oil, garlic, cilantro, and salt. Ingredients are usually blended together using a blender or food processor.
Ají has been prepared in Andean countries such as Bolivia, Colombia, and Peru since at least the time of the Incas, who called it uchu. It is usually added to other foods such as anticuchos, chugchucaras, soup, chorizo, or empanadas.
In Colombia and Ecuador, food is traditionally milder, so ají can be added to almost any dish to add flavor and spice. Recipes vary dramatically from person to person and from region to region, depending on preference.
The core ingredient of ají sauce, ají peppers (Capsicum baccatum), was originally grown in South America. While these peppers have a Scoville Heat Unit of 30,000 - 50,000, depending on the variety of pepper and preparation technique, the spice level of ají sauce is variable.
Varieties
Chile
In Chile there is a related variety of the condiment known as ají chileno, which contains the additional ingredient of lemon juice.
Ecuador
In Ecuador, ají sauce is prepared using one of the over 30 ají pepper varieties available in the country. These ají peppers vary in spice level and this, combined with the amount of water used to dilute the sauce, can create variation in the level of spice between sauces. Some regions are also known for their addition of fruits, in addition to the basic ingredients, which lead
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https://en.wikipedia.org/wiki/Logical%20form
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In logic, logical form of a statement is a precisely-specified semantic version of that statement in a formal system. Informally, the logical form attempts to formalize a possibly ambiguous statement into a statement with a precise, unambiguous logical interpretation with respect to a formal system. In an ideal formal language, the meaning of a logical form can be determined unambiguously from syntax alone. Logical forms are semantic, not syntactic constructs; therefore, there may be more than one string that represents the same logical form in a given language.
The logical form of an argument is called the argument form of the argument.
History
The importance of the concept of form to logic was already recognized in ancient times. Aristotle, in the Prior Analytics, was probably the first to employ variable letters to represent valid inferences. Therefore, Jan Łukasiewicz claims that the introduction of variables was "one of Aristotle's greatest inventions."
According to the followers of Aristotle like Ammonius, only the logical principles stated in schematic terms belong to logic, and not those given in concrete terms. The concrete terms man, mortal, and so forth are analogous to the substitution values of the schematic placeholders A, B, C, which were called the "matter" (Greek hyle, Latin materia) of the argument.
The term "logical form" itself was introduced by Bertrand Russell in 1914, in the context of his program to formalize natural language and reasoning, which he called philosophical logic. Russell wrote: "Some kind of knowledge of logical forms, though with most people it is not explicit, is involved in all understanding of discourse. It is the business of philosophical logic to extract this knowledge from its concrete integuments, and to render it explicit and pure."
Example of argument form
To demonstrate the important notion of the form of an argument, substitute letters for similar items throughout the sentences in the original argument.
Origin
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https://en.wikipedia.org/wiki/Matthew%20Foreman
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Matthew Dean Foreman is an American mathematician at
University of California, Irvine. He has made notable contributions in set theory and in ergodic theory.
Biography
Born in Los Alamos, New Mexico, Foreman earned his Ph.D. from the
University of California, Berkeley in 1980 under Robert M. Solovay. His
dissertation title was Large Cardinals and Strong Model Theoretic Transfer Properties.
In addition to his mathematical work, Foreman is an avid sailor.
He and his family sailed their sailboat Veritas (a built by C&C Yachts) from North America to Europe in 2000. From 2000–2008 they sailed Veritas to the Arctic, the Shetland Islands, Scotland, Ireland, England, France, Spain, North Africa and Italy.
Notable high points were Fastnet Rock, Irish and Celtic seas and many passages including the
Maelstrom, Stad, Pentland Firth, Loch Ness, the Corryveckan and the Irish Sea.
Further south they sailed through the Chenal du Four and Raz de Sein, across the Bay of Biscay and around Cape Finisterre. After entering Gibraltar, Foreman and his family circumnavigated the Western Mediterranean. Some notable stops included: Barcelona, Morocco, Tunisia, Sicily, Naples, Sardinia and Corsica. In 2009 Foreman, his son with guest members as crew, circumnavigated Newfoundland.
Foreman has been recognized for his sailing by twice winning the Ullman Trophy.
Work
Foreman began his career in set theory. His early work with Hugh Woodin included showing that it is consistent that the generalized continuum hypothesis (see continuum hypothesis) fails at every infinite cardinal. In joint work with Menachem Magidor and Saharon Shelah he formulated Martin's maximum, a provably maximal form of Martin's axiom and showed its consistency. Foreman's later work in set theory was primarily concerned with developing the consequences of generic large cardinal axioms. He also worked on classical "Hungarian" partition relations, mostly with András Hajnal.
In the late 1980s Foreman became interested in
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https://en.wikipedia.org/wiki/Thin%20provisioning
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In computing, thin provisioning involves using virtualization technology to give the appearance of having more physical resources than are actually available. If a system always has enough resource to simultaneously support all of the virtualized resources, then it is not thin provisioned. The term thin provisioning is applied to disk layer in this article, but could refer to an allocation scheme for any resource. For example, real memory in a computer is typically thin-provisioned to running tasks with some form of address translation technology doing the virtualization. Each task acts as if it has real memory allocated. The sum of the allocated virtual memory assigned to tasks typically exceeds the total of real memory.
The efficiency of thin or thick/fat provisioning is a function of the use case, not of the technology. Thick provisioning is typically more efficient when the amount of resource used very closely approximates to the amount of resource allocated. Thin provisioning offers more efficiency where the amount of resource used is much smaller than allocated, so that the benefit of providing only the resource needed exceeds the cost of the virtualization technology used.
Just-in-time allocation differs from thin provisioning. Most file systems back files just-in-time but are not thin provisioned. Overallocation also differs from thin provisioning; resources can be over-allocated / oversubscribed without using virtualization technology, for example overselling seats on a flight without allocating actual seats at time of sale, avoiding having each consumer having a claim on a specific seat number.
Thin provisioning is a mechanism that applies to large-scale centralized computer disk-storage systems, SANs, and storage virtualization systems. Thin provisioning allows space to be easily allocated to servers, on a just-enough and just-in-time basis. Thin provisioning is called "sparse volumes" in some contexts.
Overview
Thin provisioning, in a shared-s
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https://en.wikipedia.org/wiki/Q%20cycle
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The Q cycle (named for quinol) describes a series of reactions that describe how the sequential oxidation and reduction of the lipophilic electron carrier Coenzyme Q (CoQ) between the ubiquinol and ubiquinone forms, can result in the net movement of protons across a lipid bilayer (in the case of the mitochondria, the inner mitochondrial membrane).
The Q cycle was first proposed by Peter D. Mitchell, though a modified version of Mitchell's original scheme is now accepted as the mechanism by which Complex III moves protons (i.e. how complex III contributes to the biochemical generation of the proton or pH, gradient, which is used for the biochemical generation of ATP).
The first reaction of Q cycle is the 2-electron oxidation of ubiquinol by two oxidants, c1 (Fe3+) and ubiquinone:
CoQH2 + cytochrome c1 (Fe3+) + CoQ' → CoQ + CoQ'−• + cytochrome c1 (Fe2+) + 2 H+ (intermembrane)
The second reaction of the cycle involves the 2-electron oxidation of a second ubiquinol by two oxidants, a fresh c1 (Fe3+) and the CoQ'−• produced in the first step:
CoQH2 + cytochrome c1 (Fe3+) + CoQ'−• + 2 H+ (matrix)→ CoQ + CoQ'H−2 + cytochrome c1 (Fe2+) + 2 H+ (intermembrane)
These net reactions are mediated by electron-transfer mediators including a Rieske 2Fe-2S cluster (shunt to c1) and cb (shunt to CoQ' and later to CoQ'−•)
In chloroplasts, a similar reaction is done with plastoquinone by cytochrome b6f complex.
Process
Operation of the modified Q cycle in Complex III results in the reduction of Cytochrome c, oxidation of ubiquinol to ubiquinone, and the transfer of four protons into the intermembrane space, per two-cycle process.
Ubiquinol (QH2) binds to the Qo site of complex III via hydrogen bonding to His182 of the Rieske iron-sulfur protein and Glu272 of Cytochrome b. Ubiquinone (Q), in turn, binds the Qi site of complex III. Ubiquinol is divergently oxidized (gives up one electron each) to the Rieske iron-sulfur '(FeS) protein' and to the bL heme. This oxidation
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https://en.wikipedia.org/wiki/SCinet
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SCinet is the high-performance network built annually by volunteers in support of SC (formerly Supercomputing, the International Conference for High Performance Computing, Networking, Storage and Analysis).
SCinet is the primary network for the yearly conference and is used by attendees and exhibitors to demonstrate and test high-performance computing and networking applications.
International Community
SCinet is also a hub for the international networking community. It provides a platform to share the latest research, technologies, and demonstrations for networks, network technology providers, and even software developers who are in charge of supporting HPC communities at their own institutions or organizations.
Volunteers
Nearly 200 volunteers from educational institutions, high performance
computing sites, equipment vendors, research and education networks, government agencies and telecommunications carriers collaborate via technology and in-person to design, build and operate SCinet.
While many of these credentialed individuals have volunteered at SCinet for years, first timers join the team each year. They include international
students and participants in the National Science Foundation-funded Women in IT Networking at SC (WINS) program. The 2017 SCinet team included women and men from high performance computing institutions in the U.S. and throughout the world.
History
Originated in 1991 as an initiative within the SC conference to provide networking to attendees, SCinet has grown to become the "World's Fastest Network" during the duration of the conference. For 29 years, SCinet has provided SC attendees and the high performance computing (HPC) community with the innovative network platform necessary to internationally interconnect, transport, and display HPC research during SC.
Historically, SCinet has been used as a platform to test networking technology and applications which have found their way into common use.
Research and development
In
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https://en.wikipedia.org/wiki/Integer%20lattice
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In mathematics, the -dimensional integer lattice (or cubic lattice), denoted , is the lattice in the Euclidean space whose lattice points are -tuples of integers. The two-dimensional integer lattice is also called the square lattice, or grid lattice. is the simplest example of a root lattice. The integer lattice is an odd unimodular lattice.
Automorphism group
The automorphism group (or group of congruences) of the integer lattice consists of all permutations and sign changes of the coordinates, and is of order 2n n!. As a matrix group it is given by the set of all n × n signed permutation matrices. This group is isomorphic to the semidirect product
where the symmetric group Sn acts on (Z2)n by permutation (this is a classic example of a wreath product).
For the square lattice, this is the group of the square, or the dihedral group of order 8; for the three-dimensional cubic lattice, we get the group of the cube, or octahedral group, of order 48.
Diophantine geometry
In the study of Diophantine geometry, the square lattice of points with integer coordinates is often referred to as the Diophantine plane. In mathematical terms, the Diophantine plane is the Cartesian product of the ring of all integers . The study of Diophantine figures focuses on the selection of nodes in the Diophantine plane such that all pairwise distances are integers.
Coarse geometry
In coarse geometry, the integer lattice is coarsely equivalent to Euclidean space.
Pick's theorem
Pick's theorem, first described by Georg Alexander Pick in 1899, provides a formula for the area of a simple polygon with all vertices lying on the 2-dimensional integer lattice, in terms of the number of integer points within it and on its boundary.
Let be the number of integer points interior to the polygon, and let be the number of integer points on its boundary (including both vertices and points along the sides). Then the area of this polygon is:
The example shown has interior points and boundary po
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https://en.wikipedia.org/wiki/Serum%20iron
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Serum iron is a medical laboratory test that measures the amount of circulating iron that is bound to transferrin and freely circulate in the blood. Clinicians order this laboratory test when they are concerned about iron deficiency, which can cause anemia and other problems. 65% of the iron in the body is bound up in hemoglobin molecules in red blood cells. About 4% is bound up in myoglobin molecules. Around 30% of the iron in the body is stored as ferritin or hemosiderin in the spleen, the bone marrow and the liver. Small amounts of iron can be found in other molecules in cells throughout the body. None of this iron is directly accessible by testing the serum.}
However, some iron is circulating in the serum. Transferrin is a molecule produced by the liver that binds one or two iron(III) ions, i.e. ferric iron, Fe3+; transferrin is essential if stored iron is to be moved and used. Most of the time, about 30% of the available sites on the transferrin molecule are filled. The test for serum iron uses blood drawn from veins to measure the iron ions that are bound to transferrin and circulating in the blood. This test should be done after 12 hours of fasting. The extent to which sites on transferrin molecules are filled by iron ions can be another helpful clinical indicator, known as percent transferrin saturation. Another lab test saturates the sample to measure the total amount of transferrin; this test is called total iron-binding capacity (TIBC). These three tests are generally done at the same time, and taken together are an important part of the diagnostic process for conditions such as anemia, iron deficiency anemia, anemia of chronic disease and haemochromatosis.
Normal values
Normal reference ranges are:
Serum iron:
Men: 65 to 176 μg/dL
Women: 50 to 170 μg/dL
Newborns: 100 to 250 μg/dL
Children: 50 to 120 μg/dL
TIBC: 240–450 μg/dL
Transferrin saturation: 20–50%
μg/dL = micrograms per deciliter.
Laboratories often use different units and "normal"
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https://en.wikipedia.org/wiki/Rubber%20science
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Rubber science is a science fiction term describing a quasi-scientific explanation for an aspect of a science fiction setting. Rubber science explanations are fictional but convincing enough to avoid upsetting the suspension of disbelief. Rubber science is a feature of most genres of science fiction, with the exception of hard science fiction. It is also frequently invoked in comic books.
Coinage
The term rubber science was coined by Norman Spinrad in his essay "Rubber Sciences", published in Reginald Bretnor's anthology The Craft of Science Fiction (1976). Rubber science was Spinrad's term for "pseudo-science ... made up by the writer with literary care that it not be discontinuous with the reader's realm of the possible." In "Rubber Sciences," Spinrad proposed eight rules of rubber science to write plausibly about future technology:
Explanations must feel scientifically correct and have internal consistency.
Principles used for plot purposes must be planted in the reader's mind long before they are used as plot elements.
Concepts shouldn't be over-explained; a theoretical basis is sufficient.
When creating a new science, authors should pay attention to how established sciences evolve.
Interfacing two or more existing sciences will create a plausible new science.
Plausibility can be lent by systematizing terminology and relating it to existing human knowledge by choosing words for metaphorical resonance.
Rubber science can be solidified with believable hardware.
Rubber science can "contribute to the dialectic of scientific evolution" as a tool for intellectually exploring the unknown.
Usage
The term and concept have been adopted by science fiction writers to describe science based on "speculation, extrapolation, fabrication or invention."
In their writing guide On Writing Science Fiction, George H. Scithers, Darrell Schweitzer, and John M. Ford cite Spinrad's rules for rubber science as a way to "play fair with the reader," building a background logically from
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https://en.wikipedia.org/wiki/List%20of%20Rhodesian%20flags
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This is a list of flags used in Southern Rhodesia between 1890–1964 and 1979–1980 and Rhodesia between 1964 and 1979. The evolution of Southern Rhodesia from a British South African Company concern, to a British Colony, then to a member of a Federal Government, then to a self-declared state is evident by the different flags used.
For flags after these dates see Flags of Zimbabwe.
National flags
Vice-regal and presidential
Military flags
Political flags
Town flags
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https://en.wikipedia.org/wiki/186%20%28number%29
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186 (one hundred [and] eighty-six) is the natural number following 185 and preceding 187.
In mathematics
There is no integer with exactly 186 coprimes less than it, so 186 is a nontotient. It is also never the difference between an integer and the total of coprimes below it, so it is a noncototient.
There are 186 different pentahexes, shapes formed by gluing together five regular hexagons, when rotations of shapes are counted as distinct from each other.
186 is a Fine number.
See also
The year AD 186 or 186 BC
List of highways numbered 186
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https://en.wikipedia.org/wiki/Tragacanth
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Tragacanth is a natural gum obtained from the dried sap of several species of Middle Eastern legumes of the genus Astragalus, including A. adscendens, A. gummifer, A. brachycalyx, and A. tragacantha. Some of these species are known collectively under the common names "goat's thorn" and "locoweed". The gum is sometimes called Shiraz gum, shiraz, gum elect or gum dragon. The name derives from the Greek words tragos (meaning "goat") and akantha ("thorn"). Iran is the biggest producer of this gum.
Gum tragacanth is a viscous, odorless, tasteless, water-soluble mixture of polysaccharides obtained from sap that is drained from the root of the plant and dried. The gum seeps from the plant in twisted ribbons or flakes that can be powdered. It absorbs water to become a gel, which can be stirred into a paste. The major fractions are known as tragacanthin, highly water-soluble as a mucilaginous colloid, and the chemically related bassorin, which is far less soluble but swells in water to form a gel. The gum is used in vegetable-tanned leatherworking as an edge slicking and burnishing compound, and is occasionally used as a stiffener in textiles. The gum has been used historically as a herbal remedy for such conditions as cough and diarrhea. Powders using tragacanth as a basis were sometimes called diatragacanth. As a mucilage or paste, it has been used as a topical treatment for burns. It is used in pharmaceuticals and foods as an emulsifier, thickener, stabilizer, and texturant additive (E number E413). It is the traditional binder used in the making of artists' pastels, as it does not adhere to itself the same way other gums (such as gum arabic) do when dry. Gum tragacanth is also used to make a paste used in floral sugarcraft to create lifelike flowers on wires used as decorations for cakes, which air-dries brittle and can take colorings. It enables users to get a very fine, delicate finish to their work. It has traditionally been used as an adhesive in the cigar-rolling p
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https://en.wikipedia.org/wiki/Local-area%20augmentation%20system
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The local-area augmentation system (LAAS) is an all-weather aircraft landing system based on real-time differential correction of the GPS signal. Local reference receivers located around the airport send data to a central location at the airport. This data is used to formulate a correction message, which is then transmitted to users via a VHF Data Link. A receiver on an aircraft uses this information to correct GPS signals, which then provides a standard instrument landing system (ILS)-style display to use while flying a precision approach. The FAA has stopped using the term LAAS and has transitioned to the International Civil Aviation Organization (ICAO) terminology of ground-based augmentation system (GBAS). While the FAA has indefinitely delayed plans for federal GBAS acquisition, the system can be purchased by airports and installed as a Non-Federal navigation aid.
History
The ground-based augmentation system (GBAS) with aviation standards identified in International Civil Aviation Organization (ICAO) Standards and Recommended Practices (SARPS), Annex 10 on radio-frequency navigation provides international standards for augmentation of GPS to support precision landing. The history of these standards can trace back to efforts in the United States by the Federal Aviation Administration to develop a Local Area Augmentation System (LAAS). Many references still refer to LAAS, although the current international terminology is GBAS and GBAS Landing System (GLS).
GBAS monitors GNSS satellites and provides correction messages to users in the vicinity of the GBAS station. The monitoring enables the GBAS to detect anomalous GPS satellite behavior and alert users in a time frame appropriate for aviation uses. The GBAS provides corrections to the GPS signals with a resulting improvement in accuracy sufficient to support aircraft precision approach operations. For more information on how GBAS works, see GBAS-How It Works.
Current GBAS standards only augment a single GNSS
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https://en.wikipedia.org/wiki/Human%20iron%20metabolism
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Human iron metabolism is the set of chemical reactions that maintain human homeostasis of iron at the systemic and cellular level. Iron is both necessary to the body and potentially toxic. Controlling iron levels in the body is a critically important part of many aspects of human health and disease. Hematologists have been especially interested in systemic iron metabolism, because iron is essential for red blood cells, where most of the human body's iron is contained. Understanding iron metabolism is also important for understanding diseases of iron overload, such as hereditary hemochromatosis, and iron deficiency, such as iron-deficiency anemia.
Importance of iron regulation
Iron is an essential bioelement for most forms of life, from bacteria to mammals. Its importance lies in its ability to mediate electron transfer. In the ferrous state (Fe2+), iron acts as an electron donor, while in the ferric state (Fe3+) it acts as an acceptor. Thus, iron plays a vital role in the catalysis of enzymatic reactions that involve electron transfer (reduction and oxidation, redox). Proteins can contain iron as part of different cofactors, such as iron–sulfur clusters (Fe-S) and heme groups, both of which are assembled in mitochondria.
Cellular respiration
Human cells require iron in order to obtain energy as ATP from a multi-step process known as cellular respiration, more specifically from oxidative phosphorylation at the mitochondrial cristae. Iron is present in the iron–sulfur cluster and heme groups of the electron transport chain proteins that generate a proton gradient that allows ATP synthase to synthesize ATP (chemiosmosis).
Heme groups are part of hemoglobin, a protein found in red blood cells that serves to transport oxygen from the lungs to other tissues. Heme groups are also present in myoglobin to store and diffuse oxygen in muscle cells.
Oxygen transport
The human body needs iron for oxygen transport. Oxygen (O2) is required for the functioning and survival
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https://en.wikipedia.org/wiki/Primitive%20node
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The primitive node (or primitive knot) is the organizer for gastrulation in most amniote embryos. In birds it is known as Hensen's node, and in amphibians it is known as the Spemann-Mangold organizer. It is induced by the Nieuwkoop center in amphibians, or by the posterior marginal zone in amniotes including birds.
Diversity
In birds the organizer is known as Hensen's node, named after its discoverer Victor Hensen.
In other amniotes it is known as the primitive node.
In amphibians, it is known as the Spemann-Mangold organizer, named after Hans Spemann and Hilde Mangold, who first identified the organizer in 1924.)
In fish it is known as the embryonic shield.
All structures are as yet considered as homologous. This view is substantiated by the common expression of several genes, including goosecoid, Cnot, noggin, nodal, and the sharing of strong axis-inducing properties upon transplantation. Cell fate studies have revealed that also the overall temporal sequence in which groups of endomesodermal cells internalize along the frog blastopore and amniote primitive streak are surprisingly similar: the first cells that involute around the amphibian blastopore lip in the organizer region, and that immigrate through Hensen’s node, contribute to foregut endoderm and prechordal plate. Cells involuting further laterally in the blastopore, or entering via Hensen’s node and the anterior primitive streak, contribute to gut, notochord and somites. Gastrulation then continues along the ventroposterior blastopore lip and posterior streak region, from where cells contribute to ventral and posterior mesoderm. Adding to this, Brachyury and caudal homologues are expressed circumferentially around the blastopore lips in the frog, and along the primitive streak in chick and mouse. This would suggest that, despite their different morphology, the amniote primitive streak and the amphibian blastopore are homologous structures, that have evolved from one and the same precursor structure
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https://en.wikipedia.org/wiki/Rhamphichthyidae
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Sand knifefish are freshwater electric fish of the family Rhamphichthyidae, from freshwater habitats in South America.
Just like most part of the members of the Gymnotiformes group, they also have elongated and compressed bodies and electric organs. The long anal fin actually extends from before the pectoral fins to the tip of the tail. There is no dorsal fin. Teeth are absent in the oral jaws and the snout is very long and tubular. The nostrils are very close together. This group is sometimes known as the tubesnout knifefishes for this reason.
They are nocturnal and burrow in the sand during the day.
Genera
According to FishBase there are only three genera in this family, but a comprehensive molecular study from 2015 showed that two additional genera belong here (formerly in Hypopomidae, marked with stars* in list), and this has been followed by recent authorities.
Gymnorhamphichthys
Hypopygus*
Iracema
Rhamphichthys
Steatogenys*
See also
List of fish families
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https://en.wikipedia.org/wiki/Wireless%20Datagram%20Protocol
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Wireless Datagram Protocol (WDP) defines the movement of information from receiver to the sender and resembles the User Datagram Protocol in the Internet protocol suite.
The Wireless Datagram Protocol (WDP), a protocol in WAP architecture, covers the Transport Layer Protocols in the Internet model. As a general transport service, WDP offers to the upper layers an invisible interface independent of the underlying network technology used. In consequence of the interface common to transport protocols, the upper layer protocols of the WAP architecture can operate independently of the underlying wireless network. By letting only the transport layer deal with physical network-dependent issues, global interoperability can be acquired using mediating gateways.
See also
Wireless Application Protocol
Wireless Session Protocol
Wireless transaction protocol
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https://en.wikipedia.org/wiki/Express%20Scripts
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Express Scripts Holding Company is a pharmacy benefit management (PBM) organization. In 2017 it was the 22nd-largest company in the United States by total revenue as well as the largest pharmacy benefit management (PBM) organization in the United States. Express Scripts had 2016 revenues of $100.752 billion. Since December 20, 2018, the company has been a direct subsidiary of Bloomfield, Connecticut-based Cigna.
The term "Scripts" in the company title refers to the widely used clipped version of prescription.
Headquartered in Greater St. Louis within unincorporated North St. Louis County, Missouri, Express Scripts provides integrated pharmacy benefit management services including network-pharmacy claims processing; home delivery pharmacy services; specialty pharmacy benefit management, through its subsidiary Accredo; benefit-design consultation; drug-utilization review; formulary management; and medical and drug data analysis services to manage drug plans for health plans, self-insured employers and government agencies (both as administrator of employee benefits and public assistance programs). One of its largest clients is the United States Department of Defense's Tricare program.
Express Scripts also offers pharmacy benefit management services for workers' compensation insurance programs. The program is accredited by URAC, the nation's largest accrediting body for pharmacy benefit management companies.
The company processes pharmaceutical claims for members through a network of retail pharmacies. Its own automated pharmacies dispense medications for chronic long-term diseases, such as diabetes or heart disease, directly to members by home delivery.
On March 7, 2018, it was announced that Cigna would buy Express Scripts in a $67 billion deal.
The deal closed on December 20, 2018 at $54 billion, allowing Cigna to start offering new Express Scripts products to its corporate health insurance customers in 2019.
History
Founding
Express Scripts began in 1986 in
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https://en.wikipedia.org/wiki/Tactile%20pad
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A tactile pad is an area of skin that is particularly sensitive to pressure, temperature, or pain. Tactile pads are characterized by high concentrations of free nerve endings. In primates, the last phalanges in the fingers and toes have tactile pads, allowing very accurate manipulation of objects. This precision grip was an important evolutionary advance in primates.
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https://en.wikipedia.org/wiki/Division%20algorithm
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A division algorithm is an algorithm which, given two integers N and D (respectively the numerator and the denominator), computes their quotient and/or remainder, the result of Euclidean division. Some are applied by hand, while others are employed by digital circuit designs and software.
Division algorithms fall into two main categories: slow division and fast division. Slow division algorithms produce one digit of the final quotient per iteration. Examples of slow division include restoring, non-performing restoring, non-restoring, and SRT division. Fast division methods start with a close approximation to the final quotient and produce twice as many digits of the final quotient on each iteration. Newton–Raphson and Goldschmidt algorithms fall into this category.
Variants of these algorithms allow using fast multiplication algorithms. It results that, for large integers, the computer time needed for a division is the same, up to a constant factor, as the time needed for a multiplication, whichever multiplication algorithm is used.
Discussion will refer to the form , where
N = numerator (dividend)
D = denominator (divisor)
is the input, and
Q = quotient
R = remainder
is the output.
Division by repeated subtraction
The simplest division algorithm, historically incorporated into a greatest common divisor algorithm presented in Euclid's Elements, Book VII, Proposition 1, finds the remainder given two positive integers using only subtractions and comparisons:
R := N
Q := 0
while R ≥ D do
R := R − D
Q := Q + 1
end
return (Q,R)
The proof that the quotient and remainder exist and are unique (described at Euclidean division) gives rise to a complete division algorithm, applicable to both negative and positive numbers, using additions, subtractions, and comparisons:
function divide(N, D)
if D = 0 then error(DivisionByZero) end
if D < 0 then (Q, R) := divide(N, −D); return (−Q, R) end
if N < 0 then
(Q,R) := divide(−N, D)
if R = 0 then return (−Q
|
https://en.wikipedia.org/wiki/Nash%E2%80%93Sutcliffe%20model%20efficiency%20coefficient
|
The Nash–Sutcliffe model efficiency coefficient (NSE) is used to assess the predictive skill of hydrological models. It is defined as:
where is the mean of observed discharges, and is modeled discharge. is observed discharge at time t.
The Nash–Sutcliffe efficiency is calculated as one minus the ratio of the error variance of the modeled time-series divided by the variance of the observed time-series. In the situation of a perfect model with an estimation error variance equal to zero, the resulting Nash–Sutcliffe Efficiency equals 1 (NSE = 1). Conversely, a model that produces an estimation error variance equal to the variance of the observed time series results in a Nash–Sutcliffe Efficiency of 0.0 (NSE = 0). In reality, NSE = 0 indicates that the model has the same predictive skill as the mean of the time-series in terms of the sum of the squared error. In the case of a modeled time series with an estimation error variance that is significantly larger than the variance of the observations, the NSE becomes negative. An efficiency less than zero (NSE < 0) occurs when the observed mean is a better predictor than the model. Values of the NSE nearer to 1, suggest a model with more predictive skill. Subjective application of different NSE values as thresholds of sufficiency have been suggested by several authors. For the application of NSE in regression procedures (i.e. when the total sum of squares can be partitioned into error and regression components), the Nash–Sutcliffe efficiency is equivalent to the coefficient of determination (R2), thus ranging between 0 and 1.
In some applications such as automatic calibration or machine learning, the NSE lower limit of (-∞) creates problems. To eliminate this problem and re-scale the NSE to lie solely within the range of {0,1} normalization, use the following equation that yields a Normalized Nash–Sutcliffe Efficiency (NNSE)
Note that NSE=1 corresponds to NNSE=1, NSE=0 corresponds to NNSE=0.5, and NSE=-∞ corre
|
https://en.wikipedia.org/wiki/Block-stacking%20problem
|
In statics, the block-stacking problem (sometimes known as The Leaning Tower of Lire , also the book-stacking problem, or a number of other similar terms) is a puzzle concerning the stacking of blocks at the edge of a table.
Statement
The block-stacking problem is the following puzzle:
Place identical rigid rectangular blocks in a stable stack on a table edge in such a way as to maximize the overhang.
provide a long list of references on this problem going back to mechanics texts from the middle of the 19th century.
Variants
Single-wide
The single-wide problem involves having only one block at any given level. In the ideal case of perfectly rectangular blocks, the solution to the single-wide problem is that the maximum overhang is given by times the width of a block. This sum is one half of the corresponding partial sum of the harmonic series. Because the harmonic series diverges, the maximal overhang tends to infinity as increases, meaning that it is possible to achieve any arbitrarily large overhang, with sufficient blocks.
The number of blocks required to reach at least block-lengths past the edge of the table is 4, 31, 227, 1674, 12367, 91380, ... .
Multi-wide
Multi-wide stacks using counterbalancing can give larger overhangs than a single width stack. Even for three blocks, stacking two counterbalanced blocks on top of another block can give an overhang of 1, while the overhang in the simple ideal case is at most . As showed, asymptotically, the maximum overhang that can be achieved by multi-wide stacks is proportional to the cube root of the number of blocks, in contrast to the single-wide case in which the overhang is proportional to the logarithm of the number of blocks. However, it has been shown that in reality this is impossible and the number of blocks that we can move to the right, due to block stress, is not more than a specified number. For example, for a special brick with = , Young's modulus = and density = and limiting compress
|
https://en.wikipedia.org/wiki/Definite%20clause%20grammar
|
A definite clause grammar (DCG) is a way of expressing grammar, either for natural or formal languages, in a logic programming language such as Prolog. It is closely related to the concept of attribute grammars / affix grammars from which Prolog was originally developed.
DCGs are usually associated with Prolog, but similar languages such as Mercury also include DCGs. They are called definite clause grammars because they represent a grammar as a set of definite clauses in first-order logic.
The term DCG refers to the specific type of expression in Prolog and other similar languages; not all ways of expressing grammars using definite clauses are considered DCGs. However, all of the capabilities or properties of DCGs will be the same for any grammar that is represented with definite clauses in essentially the same way as in Prolog.
The definite clauses of a DCG can be considered a set of axioms where the validity of a sentence, and the fact that it has a certain parse tree can be considered theorems that follow from these axioms. This has the advantage of making it so that recognition and parsing of expressions in a language becomes a general matter of proving statements, such as statements in a logic programming language.
History
The history of DCGs is closely tied to the history of Prolog, and the history of Prolog revolves around several researchers in both Marseille, France, and Edinburgh, Scotland. According to Robert Kowalski, an early developer of Prolog, the first Prolog system was developed in 1972 by Alain Colmerauer and Phillipe Roussel. The first program written in the language was a large natural-language processing system. Fernando Pereira and David Warren at the University of Edinburgh were also involved in the early development of Prolog.
Colmerauer had previously worked on a language processing system called Q-systems that was used to translate between English and French. In 1978, Colmerauer wrote a paper about a way of representing grammars call
|
https://en.wikipedia.org/wiki/Overdiagnosis
|
Overdiagnosis is the diagnosis of disease that will never cause symptoms or death during a patient's ordinarily expected lifetime and thus presents no practical threat regardless of being pathologic. Overdiagnosis is a side effect of screening for early forms of disease. Although screening saves lives in some cases, in others it may turn people into patients unnecessarily and may lead to treatments that do no good and perhaps do harm. Given the tremendous variability that is normal in biology, it is inherent that the more one screens, the more incidental findings will generally be found. For a large percentage of them, the most appropriate medical response is to recognize them as something that does not require intervention; but determining which action a particular finding warrants ("ignoring", watchful waiting, or intervention) can be very difficult, whether because the differential diagnosis is uncertain or because the risk ratio is uncertain (risks posed by intervention, namely, adverse events, versus risks posed by not intervening).
Overdiagnosis occurs when a disease is diagnosed correctly, but the diagnosis is irrelevant. A correct diagnosis may be irrelevant because treatment for the disease is not available, not needed, or not wanted. Some people contend that the term "overdiagnosis" is inappropriate, and that "overtreatment" is more representative of the phenomenon.
Because most people who are diagnosed are also treated, it is difficult to assess whether overdiagnosis has occurred in an individual. Overdiagnosis in an individual cannot be determined during life. Overdiagnosis is only certain when an individual remains untreated, never develops symptoms of the disease and dies of something else. The distinction of "died with disease" versus "died of disease" is then important and relevant. Thus most of the inferences about overdiagnosis comes from the study of populations. Rapidly rising rates of testing and disease diagnosis in the setting of stable rate
|
https://en.wikipedia.org/wiki/Euler%27s%20theorem%20in%20geometry
|
In geometry, Euler's theorem states that the distance d between the circumcenter and incenter of a triangle is given by
or equivalently
where and denote the circumradius and inradius respectively (the radii of the circumscribed circle and inscribed circle respectively). The theorem is named for Leonhard Euler, who published it in 1765. However, the same result was published earlier by William Chapple in 1746.
From the theorem follows the Euler inequality:
which holds with equality only in the equilateral case.
Stronger version of the inequality
A stronger version is
where , , and are the side lengths of the triangle.
Euler's theorem for the escribed circle
If and denote respectively the radius of the escribed circle opposite to the vertex and the distance between its center and the center of
the circumscribed circle, then .
Euler's inequality in absolute geometry
Euler's inequality, in the form stating that, for all triangles inscribed in a given circle, the maximum of the radius of the inscribed circle is reached for the equilateral triangle and only for it, is valid in absolute geometry.
See also
Fuss' theorem for the relation among the same three variables in bicentric quadrilaterals
Poncelet's closure theorem, showing that there is an infinity of triangles with the same two circles (and therefore the same R, r, and d)
List of triangle inequalities
|
https://en.wikipedia.org/wiki/Noise%20%28video%29
|
Noise, commonly known as static, white noise, static noise, or snow, in analog video and television, is a random dot pixel pattern of static displayed when no transmission signal is obtained by the antenna receiver of television sets and other display devices.
Description
The random pixel pattern is superimposed on the picture or the television screen, being visible as a random flicker of "dots", "snow" or "fuzzy zig-zags" in some television sets, is the result of electronic noise and radiated electromagnetic noise accidentally picked up by the antenna like air or cable. This effect is most commonly seen with analog TV sets, blank VHS tapes, or other display devices.
There are many sources of electromagnetic noise which cause the characteristic display patterns of static. Atmospheric sources of noise are the most ubiquitous, and include electromagnetic signals prompted by cosmic microwave background radiation, or more localized radio wave noise from nearby electronic devices.
The display device itself is also a source of noise, due in part to thermal noise produced by the inner electronics. Most of this noise comes from the first transistor the antenna is attached to.
Names
UK viewers used to see "snow" on black after sign-off, instead of "bugs" on white, a purely technical artifact due to old 405-line British senders using positive rather than the negative video modulation used in Canada, the US, and (currently) the UK as well. Since one impression of the "snow" is of fast-flickering black bugs on a white background, the phenomenon is often called myrornas krig in Swedish, myrekrig in Danish, hangyák háborúja in Hungarian, Ameisenkrieg in German, and semut bertengkar in Indonesian, which all translate to 'war of the ants'.
It is also known as ekran karıncalanması in Turkish, meaning 'ants on the screen', hangyafoci 'ant football' in Hungarian, and purici 'fleas' in Romanian. In French however, this phenomenon is mostly called neige 'snow', just like in Dutc
|
https://en.wikipedia.org/wiki/Radio%20noise
|
In radio reception, radio noise (commonly referred to as radio static) is unwanted random radio frequency electrical signals, fluctuating voltages, always present in a radio receiver in addition to the desired radio signal. Radio noise near in frequency to the radio signal being received (in the receiver's passband) interferes with it in the receiver's circuits. Radio noise is a combination of natural electromagnetic atmospheric noise ("spherics", static) created by electrical processes in the atmosphere like lightning, manmade radio frequency interference (RFI) from other electrical devices picked up by the receiver's antenna, and thermal noise present in the receiver input circuits, caused by the random thermal motion of molecules.
The level of noise determines the maximum sensitivity and reception range of a radio receiver; if no noise were picked up with radio signals, even weak transmissions could be received at virtually any distance by making a radio receiver that was sensitive enough. With noise present, if a radio source is so weak and far away that the radio signal in the receiver has a lower amplitude than the average noise, the noise will drown out the signal. The level of noise in a communications circuit is measured by the signal-to-noise ratio (S/N), the ratio of the average amplitude of the signal voltage to the average amplitude of the noise voltage. When this ratio is below one (0 dB) the noise is greater than the signal, requiring special processing to recover the information.
The limiting noise source in a receiver depends on the frequency range in use. At frequencies below about 40 MHz, particularly in the mediumwave and longwave bands and below, atmospheric noise and nearby radio frequency interference from electrical switches, motors, vehicle ignition circuits, computers, and other man-made sources tend to be above the thermal noise floor in the receiver's circuits.
These noises are often referred to as static. Conversely, at very high fr
|
https://en.wikipedia.org/wiki/Automatic%20switched-transport%20network
|
Automatic Switched Transport Network (ASTN) allows traffic paths to be set up through a switched network automatically. The term ASTN replaces the term ASON (Automatically Switched Optical Network) and is often used interchangeably with GMPLS (Generalized MPLS). This is not completely correct as GMPLS is a family of protocols, but ASON/ASTN is an optical/transport network architecture. The requirements of the ASON/ASTN architecture can be satisfied using GMPLS protocols developed by the IETF or by GMPLS protocols that have been modified by the ITU. Furthermore, the GMPLS protocols are applicable to optical and non-optical (e.g., packet and frame) networks, and can be used in transport or client networks. Thus, GMPLS is a wider concept than ASTN.
Traditionally, creating traffic paths through a series of Network Elements has involved configuration of individual cross-connects on each Network Element. ASTN allows the user to specify the start point, end point and bandwidth required, and the ASTN agent on the Network Elements will allocate the path through the network, provisioning the traffic path, setting up cross-connects, and allocating bandwidth from the paths for the user requested service. The actual path that the traffic will take through the network is not specified by the user.
Changes to the network (adding/removing nodes) will be taken into account by the ASTN agents in the network, but do not need to be considered by the user. This gives the user far more flexibility when allocating user bandwidth to provide services demanded by the customer.
GMPLS consist of several protocols, including routing protocols (OSPF-TE or ISIS-TE), link management protocols (LMP), and a reservation/label distribution protocol (RSVP-TE). The reservation/label distribution protocol CR-LDP has now been deprecated by the IETF in RFC 3468 (February 2003) and IETF GMPLS working group decided to focus purely on RSVP-TE.
The GMPLS architecture is defined in RFC 3945.
|
https://en.wikipedia.org/wiki/N-Methyl-2-pyrrolidone
|
N-Methyl-2-pyrrolidone (NMP) is an organic compound consisting of a 5-membered lactam. It is a colorless liquid, although impure samples can appear yellow. It is miscible with water and with most common organic solvents. It also belongs to the class of dipolar aprotic solvents such as dimethylformamide and dimethyl sulfoxide. It is used in the petrochemical, polymer and battery industries as a solvent, exploiting its nonvolatility and ability to dissolve diverse materials (including polyvinylidene difluoride, PVDF).
Preparation
NMP is produced industrially by a typical ester-to-amide conversion, by treating butyrolactone with methylamine. Alternative routes include the partial hydrogenation of N-methylsuccinimide and the reaction of acrylonitrile with methylamine followed by hydrolysis. About 200,000 to 250,000 tons are produced annually.
Applications
NMP is used to recover certain hydrocarbons generated in the processing of petrochemicals, such as the recovery of 1,3-butadiene and acetylene. It is used to absorb hydrogen sulfide from sour gas and hydrodesulfurization facilities. Its good solvency properties have led to NMP's use to dissolve a wide range of polymers. Specifically, it is used as a solvent for surface treatment of textiles, resins, and metal coated plastics or as a paint stripper. It is also used as a solvent in the commercial preparation of polyphenylene sulfide. In the pharmaceutical industry, N-methyl-2-pyrrolidone is used in the formulation for drugs by both oral and transdermal delivery routes. It is also used heavily in lithium ion battery fabrication, as a solvent for electrode preparation, because NMP has a unique ability to dissolve polyvinylidene fluoride binder. Due to NMP's toxicity and high boiling point, there is much effort to replace it in battery manufacturing with other solvent(s), like water.
Health hazards
N-Methyl-2-pyrrolidone is an agent that causes the production of physical defects in the developing embryo. It also
|
https://en.wikipedia.org/wiki/Signcryption
|
In cryptography, signcryption is a public-key primitive that simultaneously performs the functions of both digital signature and encryption.
Encryption and digital signature are two fundamental cryptographic tools that can guarantee the confidentiality, integrity, and non-repudiation. Until 1997, they were viewed as important but distinct building blocks of various cryptographic systems. In public key schemes, a traditional method is to digitally sign a message then followed by an encryption (signature-then-encryption) that can have two problems: Low efficiency and high cost of such summation, and the case that any arbitrary scheme cannot guarantee security. Signcryption is a relatively new cryptographic technique that is supposed to perform the functions of digital signature and encryption in a single logical step and can effectively decrease the computational costs and communication overheads in comparison with the traditional signature-then-encryption schemes.
Signcryption provides the properties of both digital signatures and encryption schemes in a way that is more efficient than signing and encrypting separately. This means that at least some aspect of its efficiency (for example the computation time) is better than any hybrid of digital signature and encryption schemes, under a particular model of security. Note that sometimes hybrid encryption can be employed instead of simple encryption, and a single session-key reused for several encryptions to achieve better overall efficiency across many signature-encryptions than a signcryption scheme but the session-key reuse causes the system to lose security under even the relatively weak CPA model. This is the reason why a random session key is used for each message in a hybrid encryption scheme but for a given level of security (i.e., a given model, say CPA), a signcryption scheme should be more efficient than any simple signature-hybrid encryption combination.
History
The first signcryption scheme was introd
|
https://en.wikipedia.org/wiki/Elitzur%E2%80%93Vaidman%20bomb%20tester
|
The Elitzur–Vaidman bomb-tester is a quantum mechanics thought experiment that uses interaction-free measurements to verify that a bomb is functional without having to detonate it. It was conceived in 1993 by Avshalom Elitzur and Lev Vaidman. Since their publication, real-world experiments have confirmed that their theoretical method works as predicted.
The bomb tester takes advantage of two characteristics of elementary particles, such as photons or electrons: nonlocality and wave–particle duality. By placing the particle in a quantum superposition, it is possible for the experiment to verify that the bomb works without triggering its detonation, although there is still a 50% chance that the bomb will detonate in the effort.
Background
The bomb test is an interaction-free measurement. The idea of getting information about an object without interacting with it is not a new one. For example, there are two boxes, one of which contains something, the other of which contains nothing. If you open one box and see nothing, you know that the other contains something, without ever opening it.
This experiment has its roots in the double-slit experiment and other, more complex concepts which inspired it, including Schrödinger's cat, and Wheeler's delayed-choice experiment. The behavior of elementary particles is very different from what we experience in our macroscopic world. Their observed behavior can be that of a wave or of a particle (see wave–particle duality), their wave-like behavior implies what is called "superposition".
In this state, some properties of the particle, for example, its location, are not definite. While in a superposition, any and all possibilities are equally real. So, if the particle could feasibly exist in more than one location, in certain senses that are experimentally useful, it exists in all of them simultaneously. The particle's wave can later be "collapsed" by observing it, at which time its location (or other measured property) at the momen
|
https://en.wikipedia.org/wiki/Medial%20triangle
|
In Euclidean geometry, the medial triangle or midpoint triangle of a triangle is the triangle with vertices at the midpoints of the triangle's sides . It is the case of the midpoint polygon of a polygon with sides. The medial triangle is not the same thing as the median triangle, which is the triangle whose sides have the same lengths as the medians of .
Each side of the medial triangle is called a midsegment (or midline). In general, a midsegment of a triangle is a line segment which joins the midpoints of two sides of the triangle. It is parallel to the third side and has a length equal to half the length of the third side.
Properties
The medial triangle can also be viewed as the image of triangle transformed by a homothety centered at the centroid with ratio -1/2. Thus, the sides of the medial triangle are half and parallel to the corresponding sides of triangle ABC. Hence, the medial triangle is inversely similar and shares the same centroid and medians with triangle . It also follows from this that the perimeter of the medial triangle equals the semiperimeter of triangle , and that the area is one quarter of the area of triangle . Furthermore, the four triangles that the original triangle is subdivided into by the medial triangle are all mutually congruent by SSS, so their areas are equal and thus the area of each is 1/4 the area of the original triangle.
The orthocenter of the medial triangle coincides with the circumcenter of triangle . This fact provides a tool for proving collinearity of the circumcenter, centroid and orthocenter. The medial triangle is the pedal triangle of the circumcenter. The nine-point circle circumscribes the medial triangle, and so the nine-point center is the circumcenter of the medial triangle.
The Nagel point of the medial triangle is the incenter of its reference triangle.
A reference triangle's medial triangle is congruent to the triangle whose vertices are the midpoints between the reference triangle's orthocenter a
|
https://en.wikipedia.org/wiki/Hoop%20conjecture
|
The hoop conjecture, proposed by Kip Thorne in 1972, states that an imploding object forms a black hole when, and only when, a circular hoop with a specific critical circumference could be placed around the object and rotated about its diameter. In simpler terms, the entirety of the object's mass must be compressed to the point that it resides in a perfect sphere whose radius is equal to that object's Schwarzschild radius, if this requirement is not met, then a black hole will not be formed. The critical circumference required for the imaginary hoop is given by the following equation listed below.
where
is the critical circumference;
is the object's Schwarzschild radius;
Thorne calculated the effects of gravitation on objects of different shapes (spheres, and cylinders that are infinite in one direction), and concluded that the object needed to be compressed in all three directions before gravity led to the formation of a black hole. With cylinders, the event horizon was formed when the object could fit inside the hoop described above. The mathematics to prove the same for objects of all shapes was too difficult for him at that time, but he formulated his hypothesis as the hoop conjecture.
See also
General relativity
Bounding sphere
|
https://en.wikipedia.org/wiki/Noise%20measurement
|
In acoustics, noise measurement can be for the purpose of measuring environmental noise or measuring noise in the workplace. Applications include monitoring of construction sites, aircraft noise, road traffic noise, entertainment venues and neighborhood noise. One of the definitions of noise covers all "unwanted sounds". When sound levels reach a high enough intensity, the sound, whether it is wanted or unwanted, may be damaging to hearing. Environmental noise monitoring is the measurement of noise in an outdoor environment caused by transport (e.g. motor vehicles, aircraft, and trains), industry (e.g. machines) and recreational activities (e.g. music). The laws and limits governing environmental noise monitoring differ from country to country.
At the very least, noise may be annoying or displeasing or may disrupt the activity or balance of human or animal life, increasing levels of aggression, hypertension and stress. In the extreme, excessive levels or periods of noise can have long-term negative health effects such as hearing loss, tinnitus, sleep disturbances, a rise in blood pressure, an increase in stress and vasoconstriction, and an increased incidence of coronary artery disease. In animals, noise can increase the risk of death by altering predator or prey detection and avoidance, interfering with reproduction and navigation, and contributing to permanent tinnitus and hearing loss.
Various interventions are available to combat environmental noise. Roadway noise can be reduced by the use of noise barriers, limitation of vehicle speeds, alteration of roadway surface texture, limitation of heavy vehicles, use of traffic controls that smooth vehicle flow to reduce braking and acceleration, and tire design. Aircraft noise can be reduced by using quieter jet engines, altering flight paths and considering the time of day to benefit residents near airports. Industrial noise is addressed by redesign of industrial equipment, shock mounted assemblies and physical bar
|
https://en.wikipedia.org/wiki/O.S.%20Engines
|
O.S. Engines is a Japanese model engine manufacturer.
The company was founded in 1936 by machinist Shigeo Ogawa ("Ogawa Shigeo" in the Japanese surname-first tradition) for the production of model steam engines. The name of the firm could have either originated from the traditional Japanese family-name-first tradition being the source of the "OS" name, or from the firm's actual Japanese name, "Ogawa Seisakusho". At the suggestion of American buyer Paul Houghton, Ogawa tooled up for his first gasoline-powered engine, the 1.6 cc O.S. Type-1 of which 200 units were produced and exported under the brand name, "Pixie." After World War II, Ogawa Seisakusho expanded to produce the MAX line of engines, which won acclaim for their performance and durability.
In 1976, OS pioneered the field of modern four-stroke glow plug ignition model engines with the "FS-60" 10 cm3 displacement exposed valve gear engine, and has been one of the top producers of four-stroke glow-plug-ignition model engines worldwide ever since.
O.S. Engines produces a much larger line of engines that included the only available Wankel rotary aircraft engine], which was first introduced in 1970, in cooperation with Graupner of Germany. Since Graupner's demise in 2012, O.S. continued to makes this 4.9 cm3 displacement engine on their own, still under license from NSU.
The 1980s brought increasing competition, which increased across the 1990s and into the 21st century. O.S. is now a leading manufacturer of single- and multi-cylinder model aircraft engines ranging from the small .10 LA two-stroke to the FF-320 four-stroke "giant-scale" flat four-cylinder and the FR7-420 Sirius7 7-Cylinder Radial Engine "giant-scale" radial.
O.S. engines in current production include the .21 TM, the .18 TZ, the .46 AX and many others. O.S. also makes required accessories for their engines including glow plugs, exhausts/mufflers and air filters.
O.S. has also extended their expertise to model cars, offering many reliable a
|
https://en.wikipedia.org/wiki/Raptor%20code
|
In computer science, Raptor codes (rapid tornado; see Tornado codes) are the first known class of fountain codes with linear time encoding and decoding. They were invented by Amin Shokrollahi in 2000/2001 and were first published in 2004 as an extended abstract. Raptor codes are a significant theoretical and practical improvement over LT codes, which were the first practical class of fountain codes.
Raptor codes, as with fountain codes in general, encode a given source block of data consisting of a number k of equal size source symbols into a potentially limitless sequence of encoding symbols such that reception of any k or more encoding symbols allows the source block to be recovered with some non-zero probability. The probability that the source block can be recovered increases with the number of encoding symbols received above k becoming very close to 1, once the number of received encoding symbols is only very slightly larger than k. For example, with the latest generation of Raptor codes, the RaptorQ codes, the chance of decoding failure when k encoding symbols have been received is less than 1%, and the chance of decoding failure when k+2 encoding symbols have been received is less than one in a million. (See Recovery probability and overhead section below for more discussion on this.) A symbol can be any size, from a single byte to hundreds or thousands of bytes.
Raptor codes may be systematic or non-systematic. In the systematic case, the symbols of the original source block, i.e. the source symbols, are included within the set of encoding symbols. Some examples of a systematic Raptor code is the use by the 3rd Generation Partnership Project in mobile cellular wireless broadcasting and multicasting, and also by DVB-H standards for IP datacast to handheld devices (see external links). The Raptor codes used in these standards is also defined in IETF RFC 5053.
Online codes are an example of a non-systematic fountain code.
RaptorQ code
The most advance
|
https://en.wikipedia.org/wiki/Adaptive%20value
|
The adaptive value represents the combined influence of all characters which affect the fitness of an individual or population.
Definition
Adaptive value is an essential concept of population genetics. It represents usefulness of a trait that can help an organism to survive in its environment. This heritable trait that can help offspring to cope with the new surrounding or condition is a measurable quantity. Measuring adaptive value increases our understanding of how a trait helps an individual's or population's chances of survival in a particular set of conditions.
Measurement
The adaptive value can be measured by contribution of an individual to the gene pool of their offspring. The adaptive values are approximately calculated from the rates of change in frequency and mutation–selection balance.
Examples
Avoiding Predators Some plants use indirect plant defenses to protect themselves against their herbivorous consumers. One of defensive mechanism that plants employ is to release volatile chemicals when herbivores are feeding from them. The odor of volatile chemical attracts carnivores’ attention, and they get rid of herbivores by eating them.
Sexual Reproduction Advantages Sexual mimicry is common among animals. Male cuttlefishes uses this strategy to gain advantage over other males competitor. They mimic female cuttlefish's marking to fool guarding male and fertilize their females. This strategy has more success rate than normal courtship.
See also
Adaptation
Evolution
External links
http://www.talkorigins.org/indexcc/CB/CB950.html
|
https://en.wikipedia.org/wiki/Glucocerebroside
|
Glucocerebroside (also called glucosylceramide) is any of the cerebrosides in which the monosaccharide head group is glucose.
Clinical significance
In Gaucher's disease, the enzyme glucocerebrosidase is nonfunctional and cannot break down glucocerebroside into glucose and ceramide in the lysosome. Affected macrophages, called Gaucher cells, have a distinct appearance similar to "wrinkled tissue paper" under light microscopy, because the substrates build-up within the lysosome.
See also
Glucosylceramide synthase
Gaucher's disease
Glucocerebrosidase
|
https://en.wikipedia.org/wiki/Maltol
|
Maltol is a naturally occurring organic compound that is used primarily as a flavor enhancer. It is found in nature in the bark of larch trees and in the needles of pine trees, and is produced during the roasting of malt (from which it gets its name) and in the baking of bread.
It has the odor of caramel and is used to impart a pleasant aroma to foods and fragrances.
It is used as a flavor enhancer, is designated in the U.S. as INS number 636,
and is known in the European E number food additive series as E636.
Chemistry
Maltol is a white crystalline powder that is soluble in hot water and other polar solvents.
Like related 3-hydroxy-4-pyrones such as kojic acid, it binds to hard metal centers such as Fe3+, Ga3+, Al3+, and VO2+.
Related to this property, maltol has been reported to greatly increase aluminium uptake in the body and to increase the oral bioavailability of gallium and iron.
See also
Ethyl maltol
Ferric maltol
Gallium maltolate
5-Hydroxymaltol
Isomaltol
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