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https://en.wikipedia.org/wiki/Triangle%20conic | In Euclidean geometry, a triangle conic is a conic in the plane of the reference triangle and associated with it in some way. For example, the circumcircle and the incircle of the reference triangle are triangle conics. Other examples are the Steiner ellipse, which is an ellipse passing through the vertices and having its centre at the centroid of the reference triangle; the Kiepert hyperbola which is a conic passing through the vertices, the centroid and the orthocentre of the reference triangle; and the Artzt parabolas, which are parabolas touching two sidelines of the reference triangle at vertices of the triangle.
The terminology of triangle conic is widely used in the literature without a formal definition; that is, without precisely formulating the relations a conic should have with the reference triangle so as to qualify it to be called a triangle conic (see ). However, Greek mathematician Paris Pamfilos defines a triangle conic as a "conic circumscribing a triangle (that is, passing through its vertices) or inscribed in a triangle (that is, tangent to its side-lines)". The terminology triangle circle (respectively, ellipse, hyperbola, parabola) is used to denote a circle (respectively, ellipse, hyperbola, parabola) associated with the reference triangle is some way.
Even though several triangle conics have been studied individually, there is no comprehensive encyclopedia or catalogue of triangle conics similar to Clark Kimberling's Encyclopedia of Triangle Centres or Bernard Gibert's Catalogue of Triangle Cubics.
Equations of triangle conics in trilinear coordinates
The equation of a general triangle conic in trilinear coordinates has the form
The equations of triangle circumconics and inconics have respectively the forms
Special triangle conics
In the following, a few typical special triangle conics are discussed. In the descriptions, the standard notations are used: the reference triangle is always denoted by . The angles at the vertices are den |
https://en.wikipedia.org/wiki/Carbon-13%20NMR%20satellite | Carbon satellites in physics and spectroscopy, are small peaks that can be seen shouldering the main peaks in the nuclear magnetic resonance (NMR) spectrum. These peaks can occur in the NMR spectrum of any NMR active atom (e.g. 19F or 31P NMR) where those atoms adjoin a carbon atom (and where the spectrum is not 13C-decoupled, which is usually the case). However, Carbon satellites are most often encountered in proton NMR.
In the example of proton NMR, these peaks are not the result of proton-proton coupling, but result from the coupling of 1H atoms to an adjoining 13C atom. These small peaks are known as carbon satellites as they are small and appear around the main 1H peak i.e. satellite (around) to them. Carbon satellites are small because 13C only makes up about 1% of the atomic carbon content of carbon, the rest of the carbon atoms are predominantly NMR inactive 12C. Carbon satellites always appear as an evenly spaced pair around the main 1H peak. This is because they are the result of 1% of the 1H atoms coupling to an adjoined 13C atom to give a wide doublet (13C has a spin of a half). Note, if the main 1H-peak has proton-proton coupling, then each satellite will be a miniature version of the main peak and will also show this 1H-coupling, e.g. if the main 1H-peak is a doublet, then the carbon satellites will appear as miniature doublets, i.e. one doublet on either side of the main 1H-peak.
For other NMR atoms (e.g. 19F or 31P atoms), the same applies as above, but obviously where the proton atom is replaced with that other NMR active atom e.g. 31P.
Sometime other peaks can be seen around 1H peaks; these are known as spinning sidebands and are related to the rate of spin of an NMR tube. Carbon satellites (and spinning sidebands) should not be confused with impurity peaks.
Uses
Carbon satellites can be used to obtain structural information, which is not available by looking at the main peaks in the NMR spectrum.
This usually occurs when the purely 12C co |
https://en.wikipedia.org/wiki/Amorphism | An amorphism, in chemistry, crystallography and, by extension, to other areas of the natural sciences is a substance or feature that lacks an ordered form. In the specific case of crystallography, an amorphic material is one that lacks long range (significant) crystalline order at the molecular level. In the history of chemistry, amorphism was recognised even before the discovery of the nature of the exact atomic crystalline lattice structure. The concept of amorphism can also be found in the fields of art, biology, archaeology and philosophy as a characterisation of objects without form, or with random or unstructured form.
Amorphous and Crystalline solid
In the context of solids, amorphous and crystalline are terms used to describe the structure of materials. Amorphous solids are the opposite of crystalline. The atoms or molecules in amorphous substances are arranged randomly without any long-range order. As a result, they do not have a sharp melting point. The phase transition from solid to liquid occurs over a range of temperatures. Some examples include glass, rubber and some plastics.
See also
Glass
Obsidian |
https://en.wikipedia.org/wiki/List%20of%20uniform%20polyhedra | In geometry, a uniform polyhedron is a polyhedron which has regular polygons as faces and is vertex-transitive (transitive on its vertices, isogonal, i.e. there is an isometry mapping any vertex onto any other). It follows that all vertices are congruent, and the polyhedron has a high degree of reflectional and rotational symmetry.
Uniform polyhedra can be divided between convex forms with convex regular polygon faces and star forms. Star forms have either regular star polygon faces or vertex figures or both.
This list includes these:
all 75 nonprismatic uniform polyhedra;
a few representatives of the infinite sets of prisms and antiprisms;
one degenerate polyhedron, Skilling's figure with overlapping edges.
It was proven in that there are only 75 uniform polyhedra other than the infinite families of prisms and antiprisms. John Skilling discovered an overlooked degenerate example, by relaxing the condition that only two faces may meet at an edge. This is a degenerate uniform polyhedron rather than a uniform polyhedron, because some pairs of edges coincide.
Not included are:
The uniform polyhedron compounds.
40 potential uniform polyhedra with degenerate vertex figures which have overlapping edges (not counted by Coxeter);
The uniform tilings (infinite polyhedra)
11 Euclidean convex uniform tilings;
28 Euclidean nonconvex or apeirogonal uniform tilings;
Infinite number of uniform tilings in hyperbolic plane.
Any polygons or 4-polytopes
Indexing
Four numbering schemes for the uniform polyhedra are in common use, distinguished by letters:
[C] Coxeter et al., 1954, showed the convex forms as figures 15 through 32; three prismatic forms, figures 33–35; and the nonconvex forms, figures 36–92.
[W] Wenninger, 1974, has 119 figures: 1–5 for the Platonic solids, 6–18 for the Archimedean solids, 19–66 for stellated forms including the 4 regular nonconvex polyhedra, and ended with 67–119 for the nonconvex uniform polyhedra.
[K] Kaleido, 1993: The 80 figure |
https://en.wikipedia.org/wiki/Zen%205 | Zen 5 is the codename for an upcoming CPU microarchitecture by AMD, shown on their roadmap in May 2022. It is the successor to Zen 4 and is believed to use TSMC's 4 nm and 3 nm processes. It will power Ryzen 8000 mainstream desktop processors (codenamed "Granite Ridge"), high-end mobile processors (codenamed "Strix Point"), and Epyc 9005 server processors (codenamed "Turin").
Zen 5c
Zen 5c is a compact variant of the Zen 5 core, primarily targeted at hyperscale cloud compute server customers. It will succeed the Zen 4c core. |
https://en.wikipedia.org/wiki/Rashba%20effect | The Rashba effect, also called Bychkov–Rashba effect, is a momentum-dependent splitting of spin bands in bulk crystals and low-dimensional condensed matter systems (such as heterostructures and surface states) similar to the splitting of particles and anti-particles in the Dirac Hamiltonian. The splitting is a combined effect of spin–orbit interaction and asymmetry of the crystal potential, in particular in the direction perpendicular to the two-dimensional plane (as applied to surfaces and heterostructures). This effect is named in honour of Emmanuel Rashba, who discovered it with Valentin I. Sheka in 1959 for three-dimensional systems and afterward with
Yurii A. Bychkov in 1984 for two-dimensional systems.
Remarkably, this effect can drive a wide variety of novel physical phenomena, especially operating electron spins by electric fields, even when it is a small correction to the band structure of the two-dimensional metallic state. An example of a physical phenomenon that can be explained by Rashba model is the anisotropic magnetoresistance (AMR).
Additionally, superconductors with large Rashba splitting are suggested as possible realizations of the elusive Fulde–Ferrell–Larkin–Ovchinnikov (FFLO) state, Majorana fermions and topological p-wave superconductors.
Lately, a momentum dependent pseudospin-orbit coupling has been realized in cold atom systems.
Hamiltonian
The Rashba effect is most easily seen in the simple model Hamiltonian known as the Rashba Hamiltonian
,
where is the Rashba coupling, is the momentum and is the Pauli matrix vector.
This is nothing but a two-dimensional version of the Dirac Hamiltonian (with a 90 degree rotation of the spins).
The Rashba model in solids can be derived in the framework of the k·p perturbation theory or from the point of view of a tight binding approximation. However, the specifics of these methods are considered tedious and many prefer an intuitive toy model that gives qualitatively the same physics (quantita |
https://en.wikipedia.org/wiki/Microsoft%20Analysis%20Services | Microsoft SQL Server Analysis Services (SSAS) is an online analytical processing (OLAP) and data mining tool in Microsoft SQL Server. SSAS is used as a tool by organizations to analyze and make sense of information possibly spread out across multiple databases, or in disparate tables or files. Microsoft has included a number of services in SQL Server related to business intelligence and data warehousing. These services include Integration Services, Reporting Services and Analysis Services. Analysis Services includes a group of OLAP and data mining capabilities and comes in two flavors multidimensional and tabular, where the difference between the two is how the data is presented. In a tabular model, the information is arranged in two-dimensional tables which can thus be more readable for a human. A multidimensional model can contain information with many degrees of freedom, and must be unfolded to increase readability by a human.
History
In 1996, Microsoft began its foray into the OLAP Server business by acquiring the OLAP software technology from Canada-based Panorama Software.
Just over two years later, in 1998, Microsoft released OLAP Services as part of SQL Server 7. OLAP Services supported MOLAP, ROLAP, and HOLAP architectures, and it used OLE DB for OLAP as the client access API and MDX as a query language. It could work in client-server mode or offline mode with local cube files.
In 2000, Microsoft released Analysis Services 2000. It was renamed from "OLAP Services" due to the inclusion of data mining services. Analysis Services 2000 was considered an evolutionary release, since it was built on the same architecture as OLAP Services and was therefore backward compatible with it. Major improvements included more flexibility in dimension design through support of parent child dimensions, changing dimensions, and virtual dimensions. Another feature was a greatly enhanced calculation engine with support for unary operators, custom rollups, and cell calculation |
https://en.wikipedia.org/wiki/Indecomposability%20%28intuitionistic%20logic%29 | In intuitionistic analysis and in computable analysis, indecomposability or indivisibility (, from the adjective unzerlegbar) is the principle that the continuum cannot be partitioned into two nonempty pieces. This principle was established by Brouwer in 1928 using intuitionistic principles, and can also be proven using Church's thesis. The analogous property in classical analysis is the fact that every continuous function from the continuum to {0,1} is constant.
It follows from the indecomposability principle that any property of real numbers that is decided (each real number either has or does not have that property) is in fact trivial (either all the real numbers have that property, or else none of them do). Conversely, if a property of real numbers is not trivial, then the property is not decided for all real numbers. This contradicts the law of the excluded middle, according to which every property of the real numbers is decided; so, since there are many nontrivial properties, there are many nontrivial partitions of the continuum.
In constructive set theory (CZF), it is consistent to assume the universe of all sets is indecomposable—so that any class for which membership is decided (every set is either a member of the class, or else not a member of the class) is either empty or the entire universe.
See also
Indecomposable continuum |
https://en.wikipedia.org/wiki/Space%20Dogs%3A%20Return%20to%20Earth | Space Dogs: Return to Earth () also known as Space Dogs: Tropical Adventure is a 2020 Russian 3D computer-animated comedy fantasy family film written by Danil Trotensko, Artem Milovanov, Mike Disa, Olga Nikiforova, Viktor Strelchencko and directed by Inna Evlannikova. The film was produced by Moscow studios KinoAtis and Gorky Film Studio. The creators from one of Russia's first national 3D animation studio rejoined to continue to animate the latest adventure of the canine heroes, Belka and Strelka.
The film is the third installment in the Space Dogs franchise, a sequel to the 2013 film Space Dogs: Adventure to the Moon and a trequel to the original record breaking film Space Dogs. The film is the final installment that marks the establishment of the Space Dogs trilogy. Based on true history, the film depicts Soviet space dogs Belka and Strelka, who are the world's first animals who were sent into space and survived the trip (on board the Korabl-Sputnik 2 mission in 1960). The film portrays the historical characters in a lighthearted comedy animation film.
Set in outer space and planet Earth, the Soviet command sends Belka and Strelka on a reconnaissance mission to the island of Cuba, where a mysterious tornado begins to pull in water off the coast of the island. The astronauts dive into the Caribbean Sea to find the true mystery.
The movie was released in Russia on 24 September 2020 and the UK on 11 December 2020 with its international title Space Dogs: Return to Earth. Epic Pictures distributed the film in North America on 2 April 2021. Critics from domestic and international countries had generally positive reviews for the film.
Plot
In the Hurricane Alley, a strange whirlpool spins out of control. Meanwhile, brave cosmonauts Belka and Strelka are in their spaceship. They see rare mineral samples somewhere in the asteroid belt near Saturn. They risk their lives to extract the samples when a call receives from Soviet command. The director reports a mysterious |
https://en.wikipedia.org/wiki/Deterministic%20memory | In computing, deterministic memory is computer memory which contains values that can be depended on from access to access. The term is also used in conjunction with achieving real-time functionality, especially in conjunction with embedded processor applications.
See also
Embedded system
Memory management
Real-time computing
External links
Design Patterns for Real-Time Computer Music Systems
Exploring memory architectures: pillars of processing performance
Harnessing parallelism from video-processing DSPs
Memory Management
Persistency Made Easy
Computer memory |
https://en.wikipedia.org/wiki/Dudley%27s%20theorem | In probability theory, Dudley's theorem is a result relating the expected upper bound and regularity properties of a Gaussian process to its entropy and covariance structure.
History
The result was first stated and proved by V. N. Sudakov, as pointed out in a paper by Richard M. Dudley. Dudley had earlier credited Volker Strassen with making the connection between entropy and regularity.
Statement
Let (Xt)t∈T be a Gaussian process and let dX be the pseudometric on T defined by
For ε > 0, denote by N(T, dX; ε) the entropy number, i.e. the minimal number of (open) dX-balls of radius ε required to cover T. Then
Furthermore, if the entropy integral on the right-hand side converges, then X has a version with almost all sample path bounded and (uniformly) continuous on (T, dX). |
https://en.wikipedia.org/wiki/Freemartin | A freemartin or free-martin (sometimes martin heifer) is an infertile female cattle with masculinized behavior and non-functioning ovaries. Phenotypically, the animal appears female, but various aspects of female reproductive development are altered due to acquisition of anti-Müllerian hormone from the male twin. Genetically, the animal is chimeric: karyotypy of a sample of cells shows XX/XY chromosomes. The animal originates as a female (XX), but acquires the male (XY) component in utero by exchange of some cellular material from a male twin, via vascular connections between placentas: an example of microchimerism. The chimerism is mainly present in the hematopoietic stem cells.
History
Freemartins are known to have been described by the Roman writer Varro, who called them .
The 18th-century physician John Hunter discovered that a freemartin always has a male twin.
It was hypothesized early in the 20th century that masculinizing factors travel from the male twin to the female twin through the vascular connections of the placenta because of the vascular fusion and affect the internal anatomy of the female.
Several researchers made the discovery that a freemartin results when a female fetus has its chorion fuse in the uterus with that of a male twin. The result was published in 1916 by Tandler and Keller. The discovery was made independently by American biologist Frank R. Lillie, who published it in Science in 1916. Both teams are now credited with the discovery.
In rural areas folklore often claimed this condition was not just peculiar to cattle, but extended also to human twins; this belief perpetuated for generations, as was mentioned in the writings of Cuthbert Bede.
Etymology
The etymology of the term "freemartin" is uncertain: speculations include that "free" may indicate "willing" (referring to the freemartin's willingness to work) or "exempt from reproduction" (referring to its sterility, or to a farmer's decision to not bother trying to breed a fr |
https://en.wikipedia.org/wiki/Theorem%20of%20corresponding%20states | According to van der Waals, the theorem of corresponding states (or principle/law of corresponding states) indicates that all fluids, when compared at the same reduced temperature and reduced pressure, have approximately the same compressibility factor and all deviate from ideal gas behavior to about the same degree.
Material constants that vary for each type of material are eliminated, in a recast reduced form of a constitutive equation. The reduced variables are defined in terms of critical variables.
The principle originated with the work of Johannes Diderik van der Waals in about 1873 when he used the critical temperature and critical pressure to derive a universal property of all fluids that follow the van der Waals equation of state. It predicts a value of that is found to be an overestimate when compared to real gases.
Edward A. Guggenheim used the phrase "Principle of Corresponding States" in an opt-cited paper to describe the phenomenon where different systems have very similar behaviors when near a critical point.
There are many examples of non-ideal gas models which satisfy this theorem, such as the van der Waals model, the Dieterici model, and so on, that can be found on the page on real gases.
Compressibility factor at the critical point
The compressibility factor at the critical point, which is defined as , where the subscript indicates physical quantities measured at the critical point, is predicted to be a constant independent of substance by many equations of state.
The table below for a selection of gases uses the following conventions:
: critical temperature [K]
: critical pressure [Pa]
: critical specific volume [m3⋅kg−1]
: gas constant (8.314 J⋅K−1⋅mol−1)
: Molar mass [kg⋅mol−1]
See also
Van der Waals equation
Equation of state
Compressibility factors
Johannes Diderik van der Waals equation
Noro-Frenkel law of corresponding states |
https://en.wikipedia.org/wiki/Lady%20Windermere%27s%20Fan%20%28mathematics%29 | In mathematics, Lady Windermere's Fan is a telescopic identity employed to relate global and local error of a numerical algorithm. The name is derived from Oscar Wilde's 1892 play Lady Windermere's Fan, A Play About a Good Woman.
Lady Windermere's Fan for a function of one variable
Let be the exact solution operator so that:
with denoting the initial time and the function to be approximated with a given .
Further let , be the numerical approximation at time , . can be attained by means of the approximation operator so that:
with
The approximation operator represents the numerical scheme used. For a simple explicit forward Euler method with step width this would be:
The local error is then given by:
In abbreviation we write:
Then Lady Windermere's Fan for a function of a single variable writes as:
with a global error of
Explanation
See also
Baker–Campbell–Hausdorff formula
Numerical error
Numerical analysis |
https://en.wikipedia.org/wiki/Soil%20gas | Soil gases (soil atmosphere) are the gases found in the air space between soil components. The spaces between the solid soil particles, if they do not contain water, are filled with air. The primary soil gases are nitrogen, carbon dioxide and oxygen. Oxygen is critical because it allows for respiration of both plant roots and soil organisms. Other natural soil gases include nitric oxide, nitrous oxide, methane, and ammonia. Some environmental contaminants below ground produce gas which diffuses through the soil such as from landfill wastes, mining activities, and contamination by petroleum hydrocarbons which produce volatile organic compounds.
Gases fill soil pores in the soil structure as water drains or is removed from a soil pore by evaporation or root absorption. The network of pores within the soil aerates, or ventilates, the soil. This aeration network becomes blocked when water enters soil pores. Not only are both soil air and soil water very dynamic parts of soil, but both are often inversely related.
Composition
The composition of gases present in the soil's pores, referred to commonly as the soil atmosphere or atmosphere of the soil, is similar to that of the Earth's atmosphere. Unlike the atmosphere, moreover, soil gas composition is less stagnant due to the various chemical and biological processes taking place in the soil. The resulting changes in composition from these processes can be defined by their variation time (i.e. daily vs. seasonal). Despite this spatial- and temporal-dependent fluctuation, soil gases typically boast greater concentrations of carbon dioxide and water vapor in comparison to the atmosphere. Furthermore, concentration of other gases, such as methane and nitrous oxide, are relatively minor yet significant in determining greenhouse gas flux and anthropogenic impact on soils.
Processes
Gas molecules in soil are in continuous thermal motion according to the kinetic theory of gases, and there is also collision between molecule |
https://en.wikipedia.org/wiki/Fish%20intelligence | Fish intelligence is the resultant of the process of acquiring, storing in memory, retrieving, combining, comparing, and using in new contexts information and conceptual skills" as it applies to fish.
According to Culum Brown from Macquarie University, "Fish are more intelligent than they appear. In many areas, such as memory, their cognitive powers match or exceed those of ‘higher’ vertebrates including non-human primates."
Fish hold records for the relative brain weights of vertebrates. Most vertebrate species have similar brain-to-body mass ratios. The deep sea bathypelagic bony-eared assfish has the smallest ratio of all known vertebrates. At the other extreme, the electrogenic elephantnose fish, an African freshwater fish, has one of the largest brain-to-body weight ratios of all known vertebrates (slightly higher than humans) and the highest brain-to-body oxygen consumption ratio of all known vertebrates (three times that for humans).
Brain
Fish typically have quite small brains relative to body size compared with other vertebrates, typically one-fifteenth the brain mass of a similarly sized bird or mammal. However, some fish have relatively large brains, most notably mormyrids and sharks, which have brains about as massive relative to body weight as birds and marsupials.
The cerebellum of cartilaginous and bony fishes is large and complex. In at least one important respect, it differs in internal structure from the mammalian cerebellum: The fish cerebellum does not contain discrete deep cerebellar nuclei. Instead, the primary targets of Purkinje cells are a distinct type of cell distributed across the cerebellar cortex, a type not seen in mammals. The circuits in the cerebellum are similar across all classes of vertebrates, including fish, reptiles, birds, and mammals. There is also an analogous brain structure in cephalopods with well-developed brains, such as octopuses. This has been taken as evidence that the cerebellum performs functions important to |
https://en.wikipedia.org/wiki/QUICC | The QUICC (Quad Integrated Communications Controller) was a Motorola 68k -based microcontroller made by Freescale Semiconductor, targeted at the telecommunications market. It lends its name to a family of successor chips called PowerQUICC.
History
The original QUICC was the Motorola 68360 (MC68360), based on the MC68302. It was followed by the PowerPC-based PowerQUICC I, PowerQUICC II, PowerQUICC II+ and PowerQUICC III.
Applications
QUICC chips form the core of many Motorola Cellular Base stations.
Many PowerQUICC II+ designs now have SATA controllers for SAN based applications.
PowerQUICC CPUs/boards come with a Linux environment. Freescale also offers MQX (a RTOS) for PPC. |
https://en.wikipedia.org/wiki/Cranopsis | The Latin word Cranopsis has been used to name animal genera of frogs, mollusks and branchiopods. Cranopsis (Cope 1875), was used for an anuran, and is a junior homonym of Cranopsis (Adams 1860), for a mollusk; and Cranopsis (Dall 1871), for a branchiopod. Cranopsis currently describes a mollusk genus in the family Fissurellidae.
The name was very briefly resurrected for a subgroup of toads (Bufo) by Frost et al. (2006a). However, Frost et al. (2006b) noted that this was a mistake, because Cranopsis was preoccupied, and they proposed Ollotis (Cope, 1975) as a replacement. Unfortunately, Ollotis is a subjective junior synonym of Incilius (Cope, 1863).
See also
Bufo |
https://en.wikipedia.org/wiki/Hilger%20%26%20Watts | Hilger & Watts was a well-known British manufacturing company that made theodolites and scientific instruments.
History
It was founded on 20 February 1948 when Adam Hilger, Ltd, founded in 1874, merged with Messrs E. R. Watts and Son by Edwin Richard Watts (1833–1901) and George William Watts (c. 1871–1954), founded in 1865. The company was taken over by the Rank Organisation in 1969 and later sold on.
Structure
It employed around 1,300 people in six factories in the late 1940s. It was situated on Camberwell Road (A215 road) in Camberwell, near the junction with the B214, between Walworth (to the north) and Camberwell (to the south) on the western edge of Burgess Park, now part of the London Borough of Southwark. There was a factory in Highbury, together with the head office in Camden Town and a small factory situated between Margate and Ramsgate in Kent. These locations were primarily "Hilger" products, whereas Camberwell was primarily Watts products. The company also had a factory at Loughton (Debden) in Essex
Products
Optical instruments
Photometers
Theodolite and surveying equipment
Tripods
Computer controlled X-ray diffractometers
Amongst other devices, the Camden location produced PDP-8 computer-driven X-ray diffractometers in the mid-late 1960s, one of which is believed to be still functional at Oxford University Chemistry Dept. in 2017. Development began with a linear diffractometer in the late 1950s - early 1960s but this was superseded around 1965 by the Y290, a four-circle diffractometer, the electronics for which were developed at the University of Manchester by Prof David B.G. Edwards (Computer Science) along with Owen S. Mills (Chemistry). The early models (actually referenced Y230) used a Ferranti computer for controlling the diffractometer but, due to reliability issues, the cheaper and more compact PDP-8 became the computer of choice for the Y290 model. One of the production engineers claimed that the electronic research department in Cam |
https://en.wikipedia.org/wiki/Leaky%20gut%20syndrome | Leaky gut syndrome is a hypothetical, medically unrecognized condition.
Unlike the scientific phenomenon of increased intestinal permeability ("leaky gut"), claims for the existence of "leaky gut syndrome" as a distinct medical condition come mostly from nutritionists and practitioners of alternative medicine. Proponents claim that a "leaky gut" causes chronic inflammation throughout the body that results in a wide range of conditions, including chronic fatigue syndrome, rheumatoid arthritis, lupus, migraines, multiple sclerosis, and autism. There is little evidence to support this hypothesis.
Stephen Barrett has described "leaky gut syndrome" as a fad diagnosis and says that its proponents use the alleged condition as an opportunity to sell a number of alternative-health remedies – including diets, herbal preparations, and dietary supplements. In 2009, Seth Kalichman wrote that some pseudoscientists claim that the passage of proteins through a "leaky" gut is the cause of autism. Evidence for claims that a leaky gut causes autism is weak and conflicting.
Advocates tout various treatments for "leaky gut syndrome", such as dietary supplements, probiotics, herbal remedies, gluten-free foods, and low-FODMAP, low-sugar, or antifungal diets, but there is little evidence that the treatments offered are of benefit.
None have been adequately tested to determine whether they are safe and effective for this purpose. The U.K. National Institute for Health and Care Excellence (NICE) does not recommend the use of any special diets to manage the main symptoms of autism or leaky gut syndrome.
See also
List of topics characterized as pseudoscience |
https://en.wikipedia.org/wiki/Stimulator%20of%20interferon%20genes | Stimulator of interferon genes (STING), also known as transmembrane protein 173 (TMEM173) and MPYS/MITA/ERIS is a protein that in humans is encoded by the STING1 gene.
STING plays an important role in innate immunity. STING induces type I interferon production when cells are infected with intracellular pathogens, such as viruses, mycobacteria and intracellular parasites. Type I interferon, mediated by STING, protects infected cells and nearby cells from local infection by binding to the same cell that secretes it (autocrine signaling) and nearby cells (paracrine signaling.) It thus plays an important role, for instance, in controlling norovirus infection.
STING works as both a direct cytosolic DNA sensor (CDS) and an adaptor protein in Type I interferon signaling through different molecular mechanisms. It has been shown to activate downstream transcription factors STAT6 and IRF3 through TBK1, which are responsible for antiviral response and innate immune response against intracellular pathogen.
Structure
Amino acids 1–379 of human STING include the 4 transmembrane regions (TMs) and a C-terminal domain. The C-terminal domain (CTD: amino acids 138–379) contains the dimerization domain (DD) and the carboxy-terminal tail (CTT: amino acids 340–379).
The STING forms a symmetrical dimer in the cell. STING dimer resembles a butterfly, with a deep cleft between the two protomers. The hydrophobic residues from each STING protomer form hydrophobic interactions between each other at the interface.
Expression
STING is expressed in hematopoietic cells in peripheral lymphoid tissues, including T lymphocytes, NK cells, myeloid cells and monocytes. It has also been shown that STING is highly expressed in lung, ovary, heart, smooth muscle, retina, bone marrow and vagina.
Localization
The subcellular localization of STING has been elucidated as an endoplasmic reticulum protein. Also, it is likely that STING associates in close proximity with mitochondria associated ER memb |
https://en.wikipedia.org/wiki/Symmetry%20of%20diatomic%20molecules | Molecular symmetry in physics and chemistry describes the symmetry present in molecules and the classification of molecules according to their symmetry. Molecular symmetry is a fundamental concept in the application of Quantum Mechanics in physics and chemistry, for example it can be used to predict or explain many of a molecule's properties, such as its dipole moment and its allowed spectroscopic transitions (based on selection rules), without doing the exact rigorous calculations (which, in some cases, may not even be possible). To do this it is necessary to classify the states of the molecule using the irreducible representations from the character table of the symmetry group of the molecule. Among all the molecular symmetries, diatomic molecules show some distinct features and they are relatively easier to analyze.
Symmetry and group theory
The physical laws governing a system is generally written as a relation (equations, differential equations, integral equations etc.). An operation on the ingredients of this relation, which keeps the form of the relations invariant is called a symmetry transformation or a symmetry of the system.
These symmetry operations can involve external or internal co-ordinates; giving rise to geometrical or internal symmetries.
These symmetry operations can be global or local; giving rise to global or gauge symmetries.
These symmetry operations can be discrete or continuous.
Symmetry is a fundamentally important concept in quantum mechanics. It can predict conserved quantities and provide quantum numbers. It can predict degeneracies of eigenstates and gives insights about the matrix elements of the Hamiltonian without calculating them. Rather than looking into individual symmetries, it is sometimes more convenient to look into the general relations between the symmetries. It turns out that Group theory is the most efficient way of doing this.
Groups
A group is a mathematical structure (usually denoted in the form (G,*)) consist |
https://en.wikipedia.org/wiki/List%20of%20tautonyms | The following is a list of tautonyms: zoological names of species consisting of two identical words (the generic name and the specific name have the same spelling). Such names are allowed in zoology, but not in botany, where the two parts of the name of a species must differ (though differences as small as one letter are permitted, as in cumin, Cuminum cyminum).
Mammals
Alces alces (Linnaeus, 1758) — Eurasian elk, moose
Axis axis (Erxleben, 1777) — chital, axis deer
Bison bison (Linnaeus, 1758) — American bison, buffalo
Capreolus capreolus (Linnaeus, 1758) — European roe deer, roe deer
Caracal caracal (Schreber, 1776) — caracal
Chinchilla chinchilla (Lichtenstein, 1829) — short-tailed chinchilla
Chiropotes chiropotes (Humboldt, 1811) — red-backed bearded saki
Cricetus cricetus (Linnaeus, 1758) — common hamster, European hamster
Crocuta crocuta (Erxleben, 1777) — spotted hyena
Dama dama (Linnaeus, 1758) — European fallow deer
Feroculus feroculus (Kelaart, 1850) — Kelaart's long-clawed shrew
Gazella gazella (Pallas, 1766) — mountain gazelle
Genetta genetta (Linnaeus, 1758) — common genet
Gerbillus gerbillus (Olivier, 1801) — lesser Egyptian gerbil
Giraffa giraffa (von Schreber, 1784) — southern giraffe
Glis glis (Linnaeus, 1766) — European edible dormouse, European fat dormouse
Gorilla gorilla (Savage, 1847) — western gorilla
Gulo gulo (Linnaeus, 1758) — wolverine
Hoolock hoolock (Harlan, 1834) — western hoolock gibbon
Hyaena hyaena (Linnaeus, 1758) — striped hyena
Indri indri (Gmelin, 1788) — indri
Jaculus jaculus (Linnaeus, 1758) — lesser Egyptian jerboa
Lagurus lagurus (Pallas, 1773) — steppe vole, steppe lemming
Lemmus lemmus (Linnaeus, 1758) — Norway lemming
Lutra lutra (Linnaeus, 1758) — European otter
Lynx lynx (Linnaeus, 1758) — Eurasian lynx
Macrophyllum macrophyllum (Schinz, 1821) — long-legged bat
Marmota marmota (Linnaeus, 1758) — Alpine marmot
Martes martes (Linnaeus, 1758) — European pine marten, pine marten
Meles meles (Linnaeus, 1758) — European badg |
https://en.wikipedia.org/wiki/Big%20q-Jacobi%20polynomials | In mathematics, the big q-Jacobi polynomials Pn(x;a,b,c;q), introduced by , are a family of basic hypergeometric orthogonal polynomials in the basic Askey scheme. give a detailed list of their properties.
Definition
The polynomials are given in terms of basic hypergeometric functions by |
https://en.wikipedia.org/wiki/Puyo%20Puyo%20%28video%20game%29 | is a puzzle video game released in 1991 by Compile for the MSX2. Since its creation, it uses characters from Madō Monogatari. It was created by Masamitsu "Moo" Niitani, the founder of Compile, who was inspired by certain elements from the Tetris and Dr. Mario series of games.
The game was released by Tokuma Shoten on the same day of the MSX2 release under the name and as part of the Famimaga Disk series for the Family Computer Disk System. A year after the MSX2 and FDS versions, Sega released an arcade version, which heavily expanded the previous versions by including a one-player story mode and a two-player competitive mode.
Gameplay
The main game of Puyo Puyo is played against at least one opponent, computer or human. The game itself has three modes, Single Puyo Puyo, Double Puyo Puyo, and Endless Puyo Puyo. In Single mode, the player takes on the role of Arle Nadja, a 16-year-old female spellcaster that has the pleasure of foiling the Dark Prince's plans. The Dark Prince wishes to take over the world, and Arle stands in his way. As such, Arle must first however battle her way through 12 opponents before facing the Dark Prince. With the exception of Rulue, they are not sent by the Dark Prince, and mostly they just want to pull shenanigans with her (for Rulue, she fell in love with the Dark Prince). Once Arle has beaten the Dark Prince, the world is saved, so she can return home. As in all main Puyo games, the story mode consists of playing Puyo matches against a fixed sequence of characters in one of three courses. In Double mode, two players play against each other. In exactly the same fashion as before, by out-chaining one another, the player tries to fill up their opponent's grid. Since the rules of sending so many garbage blocks made games short-lived, no matter how many chains are sent, Compile added the rule of Offsetting in Puyo Puyo 2 and onwards. This lets players counter opponents' attacks with chains of their own, sending any garbage blocks back to |
https://en.wikipedia.org/wiki/K-function | In mathematics, the -function, typically denoted K(z), is a generalization of the hyperfactorial to complex numbers, similar to the generalization of the factorial to the gamma function.
Definition
Formally, the -function is defined as
It can also be given in closed form as
where denotes the derivative of the Riemann zeta function, denotes the Hurwitz zeta function and
Another expression using the polygamma function is
Or using the balanced generalization of the polygamma function:
where is the Glaisher constant.
Similar to the Bohr-Mollerup Theorem for the gamma function, the log K-function is the unique (up to an additive constant) eventually 2-convex solution to the equation where is the forward difference operator.
Properties
It can be shown that for :
This can be shown by defining a function such that:
Differentiating this identity now with respect to yields:
Applying the logarithm rule we get
By the definition of the -function we write
And so
Setting we have
Now one can deduce the identity above.
The -function is closely related to the gamma function and the Barnes -function; for natural numbers , we have
More prosaically, one may write
The first values are
1, 4, 108, 27648, 86400000, 4031078400000, 3319766398771200000, ... . |
https://en.wikipedia.org/wiki/Anker%20%28unit%29 | An Anker (usually anglicized as Anchor) was a Dutch unit of capacity for wine or brandy equal to 10 US gallons that was used as a standard liquid measurement. It was most commonly used in Colonial times in New York and New Jersey, thanks to the earlier Dutch settlement of New Amsterdam (later New York City).
Many European countries had a different measurement of this unit that varied from 9 to 11 US gallons [equivalent to 7.5 to 9.25 Imperial gallons or 34 to 42 Liters].
Conversion
1 Anker ≡ 10 US gallons [8.33 Imperial gallons or 37.8541 Liters]
1 Anker ≡ 0.03785411784 m3 |
https://en.wikipedia.org/wiki/Mediation%20%28statistics%29 | In statistics, a mediation model seeks to identify and explain the mechanism or process that underlies an observed relationship between an independent variable and a dependent variable via the inclusion of a third hypothetical variable, known as a mediator variable (also a mediating variable, intermediary variable, or intervening variable). Rather than a direct causal relationship between the independent variable and the dependent variable, a mediation model proposes that the independent variable influences the mediator variable, which in turn influences the dependent variable. Thus, the mediator variable serves to clarify the nature of the relationship between the independent and dependent variables.
Mediation analyses are employed to understand a known relationship by exploring the underlying mechanism or process by which one variable influences another variable through a mediator variable. In particular, mediation analysis can contribute to better understanding the relationship between an independent variable and a dependent variable when these variables do not have an obvious direct connection.
Baron and Kenny's (1986) steps for mediation analysis
Baron and Kenny (1986) laid out several requirements that must be met to form a true mediation relationship. They are outlined below using a real-world example. See the diagram above for a visual representation of the overall mediating relationship to be explained. Note: Hayes (2009) critiqued Baron and Kenny's mediation steps approach, and as of 2019, David A. Kenny on his website stated that mediation can exist in the absence of a 'significant' total effect, and therefore step 1 below may not be needed. This situation is sometimes referred to as "inconsistent mediation". Later publications by Hayes also questioned the concepts of full or partial mediation and advocated for these terms, along with the classical mediation steps approach outlined below, to be abandoned.
Step 1
Regress the dependent variable on the i |
https://en.wikipedia.org/wiki/Hibecovirus | Hibecovirus is a subgenus of viruses in the genus Betacoronavirus, consisting of a single species, Bat Hp-betacoronavirus Zhejiang2013.
Strains forming the viral species Bat Hp-betacoronavirus Zhejiang2013 were discovered in Hipposideros pratti bats from China in 2013. |
https://en.wikipedia.org/wiki/Electronic%20stability%20control | Electronic stability control (ESC), also referred to as electronic stability program (ESP) or dynamic stability control (DSC), is a computerized technology that improves a vehicle's stability by detecting and reducing loss of traction (skidding). When ESC detects loss of steering control, it automatically applies the brakes to help steer the vehicle where the driver intends to go. Braking is automatically applied to wheels individually, such as the outer front wheel to counter oversteer, or the inner rear wheel to counter understeer. Some ESC systems also reduce engine power until control is regained. ESC does not improve a vehicle's cornering performance; instead, it helps reduce the chance of the driver losing control of the vehicle.
According to the U.S. National Highway Traffic Safety Administration and the Insurance Institute for Highway Safety in 2004 and 2006 respectively, one-third of fatal accidents could be prevented by the use of the technology. In Europe the electronic stability program has saved an estimated 15,000 lives. ESC has been mandatory in new cars in Canada, the US, and the European Union since 2011, 2012, and 2014, respectively. Worldwide, 82 percent of all new passenger cars feature the anti-skid system.
History
In 1983, a four-wheel electronic "Anti-Skid Control" system was introduced on the Toyota Crown. In 1987, Mercedes-Benz, BMW and Toyota introduced their first traction control systems. Traction control works by applying individual wheel braking and throttle to maintain traction under acceleration, but unlike ESC, it is not designed to aid in steering.
In 1990, Mitsubishi released the Diamante in Japan. It featured a new electronically controlled active trace & traction control system. Named TCL when it first entered the market, the system evolved into Mitsubishi's modern Active Skid and Traction Control (ASTC) system. Developed to help the driver maintain the intended line through a corner; an onboard computer monitored several v |
https://en.wikipedia.org/wiki/Multimedia%20telephony | The 3GPP/NGN IP Multimedia Subsystem (IMS) multimedia telephony service (MMTel) is a global standard based on the IMS, offering converged, fixed and mobile real-time multimedia communication using the media capabilities such as voice, real-time video, text, file transfer and sharing of pictures, audio and video clips. With MMTel, users have the capability to add and drop media during a session. You can start with chat, add voice (for instance Mobile VoIP), add another caller, add video, share media and transfer files, and drop any of these without losing or having to end the session. MMTel is one of the registered ICSI (IMS Communication Service Identifier) feature tags.
Description
The MMTel standard is a joint project between the 3GPP and ETSI/TISPAN standardization bodies. The MMTel standard is today the only global standard that defines an evolved telephony service that enables real-time multimedia communication with the characteristics of a telephony service over both fixed broadband, fixed narrowband and mobile access types. MMTel also provides a standardized network-to-network interface (NNI). This allow operators to interconnect their networks which in turn enables users belonging to different operators to communicate with each other, using the full set of media capabilities and supplementary services defined within the MMTel service definition.
One of the main differences with the MMTel standard is that, in contrast to legacy circuit switched telephony services, IP transport is used over the mobile access. This means that the mobile access technologies that are in main focus for MMTel are access types such as high-speed packet access (HSPA), 3GPP long-term evolution (LTE) and EDGE Evolution that all are developed with efficient IP transport in mind.
MMTel allows a single SIP session to control virtually all MMTel supplementary services and MMTel media. All available media components can easily be accessed or activated within the session. Employing a sing |
https://en.wikipedia.org/wiki/B%C3%A1rbara%20M.%20Brizuela | Bárbara M. Brizuela is an American mathematics educator, and an associate professor education at Tufts University.
Education and career
Brizuela was born in the United States, though raised in Argentina and Venezuela.
She has an Ed.D from Harvard University where she studied under Eleanor Duckworth. Prior to that, she received a Master of Arts, General Studies in Education from Tufts and a Licenciada en Ciencias Pedagógicas and Licenciada en Psicopedagogía degrees from the Universidad de Belgrano. She was a Spencer Fellow at the Harvard Graduate School of Education from 1997 until 2000 and a Roy E. Larsen Fellow in 1996–1997.
She is one of the leaders of the Tufts Math, Science, Technology and Engineering Education graduate research program.
In 2008, she received a Fulbright Fellowship.
Research
Brizuela's main research focus is on mathematics education in early childhood and elementary school. She mainly studies children's learning of written mathematical representations as well as children's construction of algebraic understandings in a line of work called "Early Algebra". She is a member of the Early Algebra Project, an NSF-funded longitudinal study of the effects of introducing some algebraic concepts to children in elementary school, and was the Principal Investigator of a study created to follow up the children of the Early Algebra study into middle and high school, also funded by the NSF. She is also involved in the Noyce Teacher Fellowship Program at Tufts and in the research effort surrounding Tufts's Poincaré Institute for Mathematics Education, an NSF NSF MSP project.
Books
In 2004, her book Mathematical Development in Young Children: Exploring Notations was published. This book was later translated into Portuguese.
In 2007, she published the book Bringing Out the Algebraic Character of Arithmetic: From Children’s Ideas to Classroom Practice with her colleagues Analúcia Schliemann and David Carraher. This book was later translated into Spanish. She |
https://en.wikipedia.org/wiki/Circular%20permutation%20in%20proteins | A circular permutation is a relationship between proteins whereby the proteins have a changed order of amino acids in their peptide sequence. The result is a protein structure with different connectivity, but overall similar three-dimensional (3D) shape. In 1979, the first pair of circularly permuted proteins – concanavalin A and lectin – were discovered; over 2000 such proteins are now known.
Circular permutation can occur as the result of evolutionary events, posttranslational modifications, or artificially engineered mutations. The two main models proposed to explain the evolution of circularly permuted proteins are permutation by duplication and fission and fusion. Permutation by duplication occurs when a gene undergoes duplication to form a tandem repeat, before redundant sections of the protein are removed; this relationship is found between saposin and swaposin. Fission and fusion occurs when partial proteins fuse to form a single polypeptide, such as in nicotinamide nucleotide transhydrogenases.
Circular permutations are routinely engineered in the laboratory to improve their catalytic activity or thermostability, or to investigate properties of the original protein.
Traditional algorithms for sequence alignment and structure alignment are not able to detect circular permutations between proteins. New non-linear approaches have been developed that overcome this and are able to detect topology-independent similarities.
History
In 1979, Bruce Cunningham and his colleagues discovered the first instance of a circularly permuted protein in nature. After determining the peptide sequence of the lectin protein favin, they noticed its similarity to a known protein – concanavalin A – except that the ends were circularly permuted. Later work confirmed the circular permutation between the pair and showed that concanavalin A is permuted post-translationally through cleavage and an unusual protein ligation.
After the discovery of a natural circularly permuted protei |
https://en.wikipedia.org/wiki/Gordon%20Bell | Chester Gordon Bell (born August 19, 1934) is an American electrical engineer and manager. An early employee of Digital Equipment Corporation (DEC) 1960–1966, Bell designed several of their PDP machines and later became Vice President of Engineering 1972–1983, overseeing the development of the VAX computer systems. Bell's later career includes entrepreneur, investor, founding Assistant Director of NSF's Computing and Information Science and Engineering Directorate 1986–1987, and researcher emeritus at Microsoft Research, 1995–2015.
Early life and education
Gordon Bell was born in Kirksville, Missouri. He grew up helping with the family business, Bell Electric, repairing appliances and wiring homes.
Bell received a BS (1956), and MS (1957) in electrical engineering from MIT. He then went to the New South Wales University of Technology (now UNSW) in Australia on a Fulbright Scholarship, where he taught classes on computer design, programmed one of the first computers to arrive in Australia (called UTECOM, an English Electric DEUCE), and published his first academic paper. Returning to the US, he worked in the MIT Speech Computation Laboratory under Professor Ken Stevens, where he wrote the first analysis by synthesis program.
Career
Digital Equipment Corporation
The DEC founders Ken Olsen and Harlan Anderson recruited him for their new company in 1960, where he designed the I/O subsystem of the PDP-1, including the first UART. Bell was the architect of the PDP-4, and PDP-6. Other architectural contributions were to the PDP-5 and PDP-11 Unibus and General Registers architecture.
After DEC, Bell went to Carnegie Mellon University in 1966 to teach computer science, but returned to DEC in 1972 as vice-president of engineering, where he was in charge of the VAX, DEC's most successful computer.
Entrepreneur and policy advisor
Bell retired from DEC in 1983 after a heart attack, but soon after founded Encore Computer, one of the first shared memory, multiple-microproc |
https://en.wikipedia.org/wiki/Group%20with%20operators | In abstract algebra, a branch of mathematics, the algebraic structure group with operators or Ω-group can be viewed as a group with a set Ω that operates on the elements of the group in a special way.
Groups with operators were extensively studied by Emmy Noether and her school in the 1920s. She employed the concept in her original formulation of the three Noether isomorphism theorems.
Definition
A group with operators can be defined as a group together with an action of a set on :
that is distributive relative to the group law:
For each , the application is then an endomorphism of G. From this, it results that a Ω-group can also be viewed as a group G with an indexed family of endomorphisms of G.
is called the operator domain. The associate endomorphisms are called the homotheties of G.
Given two groups G, H with same operator domain , a homomorphism of groups with operators is a group homomorphism satisfying
for all and
A subgroup S of G is called a stable subgroup, -subgroup or -invariant subgroup if it respects the homotheties, that is
for all and
Category-theoretic remarks
In category theory, a group with operators can be defined as an object of a functor category GrpM where M is a monoid (i.e. a category with one object) and Grp denotes the category of groups. This definition is equivalent to the previous one, provided is a monoid (otherwise we may expand it to include the identity and all compositions).
A morphism in this category is a natural transformation between two functors (i.e., two groups with operators sharing same operator domain M). Again we recover the definition above of a homomorphism of groups with operators (with f the component of the natural transformation).
A group with operators is also a mapping
where is the set of group endomorphisms of G.
Examples
Given any group G, (G, ∅) is trivially a group with operators
Given a module M over a ring R, R acts by scalar multiplication on the underlying abelian g |
https://en.wikipedia.org/wiki/Julip%20Horses%20Ltd | Julip Horses Ltd is a United Kingdom-based company which produces a range of 1/12-scale model horses.
Overview
In 1945, Lavender Dower (d. 2003) began making model horses out of chamois leather, using the lead from London buildings bombed during World War II to make their legs. Five years later the company switched to making the horses out of latex, the same material used to make the current line of Julip Originals. Dower sold the company in the 1950s. Models were sold from a shop in Beauchamp Place, London - part of the smart Knightsbridge shopping area and not far from Harrods.
Lead continued to be used to provide the support and flexibility in the legs of the latex horses until at least the early 1960s, when lead as a component of children's toys was banned in the UK for safety reasons.
Juip was just one of several companies producing cast-latex model horses in the 1950s and 1960s, but the only one to continue in business past 1968. The company's main rival was known as Isis, whose products were preferred by serious collectors of the period for their greater detail. Other companies included Pegasus and Otway, and in the late 1960s the internationally renowned animalier artist Pamela du Boulay began her sculpting career with a range of exquisite latex models sold under the 'Rydal' name.
The production process for latex models is simple, and similar to the early stages of pottery production. Plaster moulds are made from a 'master' model. When the plaster is completely dry, a mix of liquid latex and an inert 'filler' is poured into the mould and left to stand until a coating of latex has developed around the inside of the mould. The remaining liquid latex is poured away for reuse, and the casting allowed to dry out until it is firm enough to be removed from the mould. This part of the process is identical to the way ceramics are cast. With the casting removed, the plaster mould is left to dry out, and cannot be reused until 100% dry once more. Each casting pr |
https://en.wikipedia.org/wiki/Anatomical%20snuffbox | The anatomical snuff box or snuffbox or foveola radialis is a triangular deepening on the radial, dorsal aspect of the hand—at the level of the carpal bones, specifically, the scaphoid and trapezium bones forming the floor. The name originates from the use of this surface for placing and then sniffing powdered tobacco, or "snuff." It is sometimes referred to by its French name tabatière.
Structure
Boundaries
The medial border (ulnar side) of the snuffbox is the tendon of the extensor pollicis longus.
The lateral border (radial side) is a pair of parallel and intimate tendons, of the extensor pollicis brevis and the abductor pollicis longus. (Accordingly, the anatomical snuffbox is most visible, having a more pronounced concavity, during thumb extension.)
The proximal border is formed by the styloid process of the radius
The distal border is formed by the approximate apex of the schematic snuffbox isosceles triangle.
The floor of the snuffbox varies depending on the position of the wrist, but both the trapezium and primarily the scaphoid can be palpated.
Neurovascular anatomy
Deep to the tendons which form the borders of the anatomical snuff box lies the radial artery, which passes through the anatomical snuffbox on its course from the normal radial pulse detecting area, to the proximal space in between the first and second metacarpals to contribute to the superficial and deep palmar arches. In the anatomical snuffbox, the radial artery is closely related (<2 mm) with the superficial branch of radial nerve near the styloid process of radius in 48%, while in 24% the radial artery is closely related to the lateral cutaneous nerve of forearm. The cephalic vein arises within the anatomical snuffbox, while the dorsal cutaneous branch of the radial nerve can be palpated by stroking along the extensor pollicis longus with the dorsal aspect of a fingernail.
Clinical significance
The radius and scaphoid articulate deep to the snuffbox to form the basis of the wrist |
https://en.wikipedia.org/wiki/Caratheodory-%CF%80%20solution | A Carathéodory- solution is a generalized solution to an ordinary differential equation. The concept is due to I. Michael Ross and named in honor of Constantin Carathéodory. Its practicality was demonstrated in 2008 by Ross et al. in a laboratory implementation of the concept. The concept is most useful for implementing feedback controls, particularly those generated by an application of Ross' pseudospectral optimal control theory.
Mathematical background
A Carathéodory- solution addresses the fundamental problem of defining a solution to a differential equation,
when g(x,t) is not differentiable with respect to x. Such problems arise quite naturally in defining the meaning of a solution to a controlled differential equation,
when the control, u, is given by a feedback law,
where the function k(x,t) may be non-smooth with respect to x. Non-smooth feedback controls arise quite often in the study of optimal feedback controls and have been the subject of extensive study going back to the 1960s.
Ross' concept
An ordinary differential equation,
is equivalent to a controlled differential equation,
with feedback control,
. Then, given an initial value problem, Ross partitions the time interval to a grid, with . From to , generate a control trajectory,
to the controlled differential equation,
A Carathéodory solution exists for the above equation because has discontinuities at most in t, the independent variable. At , set and restart
the system with ,
Continuing in this manner, the Carathéodory segments are stitched together to form a Carathéodory- solution.
Engineering applications
A Carathéodory- solution can be applied towards the practical stabilization of a control system. It has been used to stabilize an inverted pendulum, control and optimize the motion of robots, slew and control the NPSAT1 spacecraft and produce guidance commands for low-thrust space missions.
See also
Ross' π lemma |
https://en.wikipedia.org/wiki/Quadratic%20residuosity%20problem | The quadratic residuosity problem (QRP) in computational number theory is to decide, given integers and , whether is a quadratic residue modulo or not.
Here for two unknown primes and , and is among the numbers which are not obviously quadratic non-residues (see below).
The problem was first described by Gauss in his Disquisitiones Arithmeticae in 1801.
This problem is believed to be computationally difficult.
Several cryptographic methods rely on its hardness, see .
An efficient algorithm for the quadratic residuosity problem immediately implies efficient algorithms for other number theoretic problems, such as deciding whether a composite of unknown factorization is the product of 2 or 3 primes.
Precise formulation
Given integers and , is said to be a quadratic residue modulo if there exists an integer such that
.
Otherwise we say it is a quadratic non-residue.
When is a prime, it is customary to use the Legendre symbol:
This is a multiplicative character which means for exactly of the values , and it is for the remaining.
It is easy to compute using the law of quadratic reciprocity in a manner akin to the Euclidean algorithm, see Legendre symbol.
Consider now some given where and are two, different unknown primes.
A given is a quadratic residue modulo if and only if is a quadratic residue modulo both and and .
Since we don't know or , we cannot compute and . However, it is easy to compute their product.
This is known as the Jacobi symbol:
This can also be efficiently computed using the law of quadratic reciprocity for Jacobi symbols.
However, can not in all cases tell us whether is a quadratic residue modulo or not!
More precisely, if then is necessarily a quadratic non-residue modulo either or , in which case we are done.
But if then it is either the case that is a quadratic residue modulo both and , or a quadratic non-residue modulo both and .
We cannot distinguish these cases from knowing just that .
This leads |
https://en.wikipedia.org/wiki/Jean-Paul%20Delahaye | Jean-Paul Delahaye (born 29 June 1952 in Saint-Mandé Seine) is a French computer scientist and mathematician.
Career
Delahaye has been a professor of computer science at the Lille University of Science and Technology since 1988 and a researcher in the school's computer sciences lab since 1983. Since 1991 he has written a monthly column in Pour la Science, the French version of Scientific American, dealing with mathematical games and recreations, logic, and computer science. He is a contributing author of the online scientific journal Interstices and a science and mathematics advisor to the Encyclopædia Britannica.
Delahaye won the 1998 d'Alembert prize from the Société mathématique de France for his books and articles popularizing mathematics, especially for the book Le fascinant nombre Pi.
Works
Formal Methods in Artificial Intelligence, North-Oxford Academic, 1987,
Le fascinant nombre pi, Paris: Bibliothèque Pour la Science, 1997, |
https://en.wikipedia.org/wiki/List%20of%20Nippon%20Professional%20Baseball%20mascots | The following list is a list of mascots of NPB (Nippon Professional Baseball) teams: |
https://en.wikipedia.org/wiki/Prolate%20spheroidal%20wave%20function | The prolate spheroidal wave functions are eigenfunctions of the Laplacian in prolate spheroidal coordinates, adapted to boundary conditions on certain ellipsoids of revolution (an ellipse rotated around its long axis, “cigar shape“). Related are the oblate spheroidal wave functions (“pancake shaped” ellipsoid).
Solutions to the wave equation
Solve the Helmholtz equation,
, by the method of separation of variables in prolate spheroidal coordinates, , with:
and , , and . Here, is the interfocal distance of the elliptical cross section of the prolate spheroid.
Setting , the solution can be written
as the product of , a radial spheroidal wave function and an angular spheroidal wave function .
The radial wave function satisfies the linear ordinary differential equation:
The angular wave function satisfies the differential equation:
It is the same differential equation as in the case of the radial wave function. However, the range of the variable is different: in the radial wave function, , while in the angular wave function, . The eigenvalue of this Sturm–Liouville problem is fixed by the requirement that must be finite for .
For both differential equations reduce to the equations satisfied by the associated Legendre polynomials. For , the angular spheroidal wave functions can be expanded as a series of Legendre functions.
If one writes , the function satisfies
which is known as the spheroidal wave equation. This auxiliary equation has been used by Stratton.
Band-limited signals
In signal processing, the prolate spheroidal wave functions (PSWF) are useful as eigenfunctions of a time-limiting operation followed by a low-pass filter. Let denote the time truncation operator, such that if and only if has support on . Similarly, let denote an ideal low-pass filtering operator, such that if and only if its Fourier transform is limited to . The operator turns out to be linear, bounded and self-adjoint. For we denote with the -th eigenfunction, |
https://en.wikipedia.org/wiki/Golomb%20coding | Golomb coding is a lossless data compression method using a family of data compression codes invented by Solomon W. Golomb in the 1960s. Alphabets following a geometric distribution will have a Golomb code as an optimal prefix code, making Golomb coding highly suitable for situations in which the occurrence of small values in the input stream is significantly more likely than large values.
Rice coding
Rice coding (invented by Robert F. Rice) denotes using a subset of the family of Golomb codes to produce a simpler (but possibly suboptimal) prefix code. Rice used this set of codes in an adaptive coding scheme; "Rice coding" can refer either to that adaptive scheme or to using that subset of Golomb codes. Whereas a Golomb code has a tunable parameter that can be any positive integer value, Rice codes are those in which the tunable parameter is a power of two. This makes Rice codes convenient for use on a computer since multiplication and division by 2 can be implemented more efficiently in binary arithmetic.
Rice was motivated to propose this simpler subset due to the fact that geometric distributions are often varying with time, not precisely known, or both, so selecting the seemingly optimal code might not be very advantageous.
Rice coding is used as the entropy encoding stage in a number of lossless image compression and audio data compression methods.
Overview
Construction of codes
Golomb coding uses a tunable parameter to divide an input value into two parts: , the result of a division by , and , the remainder. The quotient is sent in unary coding, followed by the remainder in truncated binary encoding. When , Golomb coding is equivalent to unary coding.
Golomb–Rice codes can be thought of as codes that indicate a number by the position of the bin (), and the offset within the bin (). The example figure shows the position and offset for the encoding of integer using Golomb–Rice parameter , with source probabilities following a geometric distrib |
https://en.wikipedia.org/wiki/Assaf%20Naor | Assaf Naor (born May 7, 1975) is an Israeli American and Czech mathematician, computer scientist, and a professor of mathematics at Princeton University.
Academic career
Naor earned a baccalaureate from Hebrew University of Jerusalem in 1996 and a doctorate from the same university in 2002, under the supervision of Joram Lindenstrauss. He worked at Microsoft Research from 2002 until 2007, with an affiliated faculty position at the University of Washington, and joined the NYU faculty in 2006.
Research
Naor's research concerns metric spaces, their properties, and related algorithms, including improved upper bounds on the Grothendieck inequality, applications of this inequality, and research on metrical task systems.
Awards and honors
Naor won the Bergmann award of the United States – Israel Binational Science Foundation in 2007, and the Pazy award of the BSF in 2011. In 2012 he was one of four faculty winners of the Leonard Blavatnik Award of the New York Academy of Sciences, given to young scientists and engineers in New York, New Jersey, and Connecticut.
He won the Salem Prize in 2008 for "contributions to the structural theory of metric spaces and its applications to computer science", and in the same year was given a European Mathematical Society Prize (one of ten awarded to outstanding younger mathematicians). He won the Bôcher Memorial Prize in 2011 "for introducing new invariants of metric spaces and for applying his new understanding of the distortion between various metric structures to theoretical computer science". In 2012 he became a fellow of the American Mathematical Society.
He received the Nemmers Prize in Mathematics in 2018 and in 2019 the Ostrowski Prize.
He gave an invited talk at the International Congress of Mathematicians in 2010, on the topic of "Functional Analysis and Applications". |
https://en.wikipedia.org/wiki/Supervisory%20program | A supervisory program or supervisor is a computer program, usually part of an operating system, that controls the execution of other routines and regulates work scheduling, input/output operations, error actions, and similar functions and regulates the flow of work in a data processing system.
It can also refer to a program that allocates computer component space and schedules computer events by task queuing and system interrupts. Control of the system is returned to the supervisory program frequently enough to ensure that demands on the system are met.
Historically, this term was essentially associated with IBM's line of mainframe operating systems starting with OS/360. In other operating systems, the supervisor is generally called the kernel.
In the 1970s, IBM further abstracted the supervisor state from the hardware, resulting in a hypervisor that enabled full virtualization, i.e. the capacity to run multiple operating systems on the same machine totally independently from each other. Hence the first such system was called Virtual Machine or VM. |
https://en.wikipedia.org/wiki/Jaccard%20index | The Jaccard index, also known as the Jaccard similarity coefficient, is a statistic used for gauging the similarity and diversity of sample sets.
It was developed by Grove Karl Gilbert in 1884 as his ratio of verification (v) and now is frequently referred to as the Critical Success Index in meteorology. It was later developed independently by Paul Jaccard, originally giving the French name coefficient de communauté, and independently formulated again by T. Tanimoto. Thus, the Tanimoto index or Tanimoto coefficient are also used in some fields. However, they are identical in generally taking the ratio of Intersection over Union.
Overview
The Jaccard coefficient measures similarity between finite sample sets, and is defined as the size of the intersection divided by the size of the union of the sample sets:
Note that by design, If A intersection B is empty, then J(A,B) = 0. The Jaccard coefficient is widely used in computer science, ecology, genomics, and other sciences, where binary or binarized data are used. Both the exact solution and approximation methods are available for hypothesis testing with the Jaccard coefficient.
Jaccard similarity also applies to bags, i.e., Multisets. This has a similar formula, but the symbols mean
bag intersection and bag sum (not union). The maximum value is 1/2.
The Jaccard distance, which measures dissimilarity between sample sets, is complementary to the Jaccard coefficient and is obtained by subtracting the Jaccard coefficient from 1, or, equivalently, by dividing the difference of the sizes of the union and the intersection of two sets by the size of the union:
An alternative interpretation of the Jaccard distance is as the ratio of the size of the symmetric difference to the union.
Jaccard distance is commonly used to calculate an n × n matrix for clustering and multidimensional scaling of n sample sets.
This distance is a metric on the collection of all finite sets.
There is also a version of the Jaccard dista |
https://en.wikipedia.org/wiki/Mode-k%20flattening | In multilinear algebra, mode-m flattening, also known as matrixizing, matricizing, or unfolding, is an operation that reshapes a multi-way array into a matrix denoted by (a two-way array).
Matrixizing may be regarded as a generalization of the mathematical concept of vectorizing.
Definition
The mode-m matrixizing of tensor is defined as the matrix . As the parenthetical ordering indicates, the mode-m column vectors are arranged by sweeping all the other mode indices through their ranges, with smaller mode indexes varying more rapidly than larger ones; thus
where and
By comparison, the matrix that results from an unfolding has columns that are the result of sweeping through all the modes in a circular manner beginning with mode as seen in the parenthetical ordering. This is an inefficient way to matrixize.
Applications
This operation is used in tensor algebra and its methods, such as Parafac and HOSVD. |
https://en.wikipedia.org/wiki/Tinkerbell%20map | The Tinkerbell map is a discrete-time dynamical system given by:
Some commonly used values of a, b, c, and d are
Like all chaotic maps, the Tinkerbell Map has also been shown to have periods; after a certain number of mapping iterations any given point shown in the map to the right will find itself once again at its starting location.
The origin of the name is uncertain; however, the graphical picture of the system (as shown to the right) shows a similarity to the movement of Tinker Bell over Cinderella Castle, as shown at the beginning of all films produced by Disney.
See also
List of chaotic maps |
https://en.wikipedia.org/wiki/Compound%20muscle%20action%20potential | The compound muscle action potential (CMAP) or compound motor action potential is an electrodiagnostic medicine investigation (electrical study of muscle function).
The CMAP idealizes the summation of a group of almost simultaneous action potentials from several muscle fibers in the same area. These are usually evoked by stimulation of the motor nerve. Patients that suffer from critical illness myopathy, which is a frequent cause of weakness seen in patients in hospital intensive care units, have prolonged compound muscle action potential. |
https://en.wikipedia.org/wiki/List%20of%20botanists%20by%20author%20abbreviation%20%28A%29 |
A
Aa – Hubertus Antonius van der Aa (1935–2017)
A.A.Burb. – Andrew A. Burbidge (fl. 2016)
A.A.Cocucci – (born 1959)
A.A.Eaton – Alvah Augustus Eaton (1865–1908)
A.A.Fisch.Waldh. – Alexandr Alexandrovich Fischer von Waldheim (1839–1920)
A.Agostini – Angela Agostini (born 1880)
A.A.Ham. – Arthur Andrew Hamilton (1855–1929)
A.A.Hend. – Andrew Augustus Henderson (1816–1876)
A.Ames – Adeline Ames (1879–1976)
A.Anderson – Alexander Anderson (1748–1811)
A.Arber – Agnes Arber (1879–1960)
Aarons. – Aaron Aaronsohn (1876–1919)
Aase – Hannah Caroline Aase (1883–1980)
A.Barbero – Andrés Barbero (1877–1951)
A.Bassi – Agostino Bassi (1773–1856)
A.Baytop – Asuman Baytop (1920–2015)
Abbayes – Henry Nicollon des Abbayes (1898–1974)
Abbiatti – Delia Abbiatti (born 1918)
Abbot – John Abbot (1751–c. 1840)
Abedin – (fl. 1986)
Aberc. – Henry McLaren, 2nd Baron Aberconway (1879–1953)
A.Berger – Alwin Berger (1871–1931)
A.B.Frank – Albert Bernhard Frank (1839–1900)
A.B.Graf – Alfred Byrd Graf (1901–2001)
A.B.Jacks. – Albert Bruce Jackson (1876–1947)
A.B.Nickels – Anna Buck Nickels (1832–1917)
A.Bloxam – Andrew Bloxam (1801–1878)
A.Blytt – Axel Gudbrand Blytt (1843–1898)
A.Br. – Addison Brown (1830–1913)
Abramov – Ivan N. Abramov (1884–1953)
Abrams – LeRoy Abrams (1874–1956)
A.Braun – Alexander Karl Heinrich Braun (1805–1877)
Abrom. – Johannes Abromeit (1857–1946)
A.Bruggen – Adolph Cornelis van Bruggen (born 1929)
A.Butler – (born 1946)
A.Cabrera – Ángel Cabrera (1879–1960) (not to be confused with botanist Ángel Lulio Cabrera (1908–1999))
A.Camus – Aimée Antoinette Camus (1879–1965)
A.Cast. – (1896–1968)
A.Cels – Auguste Cels (1809-1898)
Acerbi – Giuseppe Acerbi (1773–1846)
Ach. – Erik Acharius (1757–1819)
A.C.H.Blinks – Anne Catherine Hof Blinks (1903–1995)
A.Chev. – Auguste Jean Baptiste Chevalier (1873–1956)
Achv. – (1907–1999)
Ackerman – James David Ackerman (born 1950)
Acloque – Alexandre Noël Charles Acloque (1871–1908)
A.C.Sch |
https://en.wikipedia.org/wiki/Cataclysmic%20variable%20star | In astronomy, cataclysmic variable stars (CVs) are stars which irregularly increase in brightness by a large factor, then drop back down to a quiescent state. They were initially called novae (), since ones with an outburst brightness visible to the naked eye and an invisible quiescent brightness appeared as new stars in the sky.
Cataclysmic variable stars are binary stars that consist of two components; a white dwarf primary, and a mass transferring secondary. The stars are so close to each other that the gravity of the white dwarf distorts the secondary, and the white dwarf accretes matter from the companion. The tightest currently observed orbit in a hydrogen-rich system is 51 minutes in ZTF J1813+4251. Therefore, the secondary is often referred to as the donor star. The infalling matter, which is usually rich in hydrogen, forms in most cases an accretion disk around the white dwarf. Strong UV and X-ray emission is often detected from the accretion disc, powered by the loss of gravitational potential energy from the infalling material.
Material at the inner edge of disc falls onto the surface of the white dwarf primary. A classical nova outburst occurs when the density and temperature at the bottom of the accumulated hydrogen layer rise high enough to ignite runaway hydrogen fusion reactions, which rapidly convert the hydrogen layer to helium. If the accretion process continues long enough to bring the white dwarf close to the Chandrasekhar limit, the increasing interior density may ignite runaway carbon fusion and trigger a Type Ia supernova explosion, which would completely destroy the white dwarf.
The accretion disc may be prone to an instability leading to dwarf nova outbursts, when the outer portion of the disc changes from a cool, dull mode to a hotter, brighter mode for a time, before reverting to the cool mode. Dwarf novae can recur on a timescale of days to decades.
Classification
Cataclysmic variables are subdivided into several smaller groups, oft |
https://en.wikipedia.org/wiki/Reverse-search%20algorithm | Reverse-search algorithms are a class of algorithms for generating all objects of a given size, from certain classes of combinatorial objects. In many cases, these methods allow the objects to be generated in polynomial time per object, using only enough memory to store a constant number of objects (polynomial space). (Generally, however, they are not classed as polynomial-time algorithms, because the number of objects they generate is exponential.) They work by organizing the objects to be generated into a spanning tree of their state space, and then performing a depth-first search of this tree.
Reverse-search algorithms were introduced by David Avis and Komei Fukuda in 1991, for problems of generating the vertices of convex polytopes and the cells of arrangements of hyperplanes. They were formalized more broadly by Avis and Fukuda in 1996.
Principles
A reverse-search algorithm generates the combinatorial objects in a state space, an implicit graph whose vertices are the objects to be listed and whose edges represent certain "local moves" connecting pairs of objects, typically by making small changes to their structure. It finds each objects using a depth-first search in a rooted spanning tree of this state space, described by the following information:
The root of the spanning tree, one of the objects
A subroutine for generating the parent of each object in the tree, with the property that if repeated enough times it will eventually reach the root
A subroutine for listing all of the neighbors in the state space (not all of which may be neighbors in the tree)
From this information it is possible to find the children of any given node in the tree, reversing the links given by the parent subroutine: they are simply the neighbors whose parent is the given node. It is these reversed links to child nodes that the algorithm searches.
A classical depth-first search of this spanning tree would traverse the tree recursively, starting from the root, at each node listing |
https://en.wikipedia.org/wiki/Larder | A larder is a cool area for storing food prior to use. Originally, it was where raw meat was larded—covered in fat—to be preserved. By the 18th century, the term had expanded: at that point, a dry larder was where bread, pastry, milk, butter, or cooked meats were stored. Larders were commonplace in houses before the widespread use of the refrigerator.
Stone larders were designed to keep cold in the hottest weather. They had slate or marble shelves two or three inches thick. These shelves were wedged into thick stone walls. Fish or vegetables were laid directly onto the shelves and covered with muslin or handfuls of wet rushes were sprinkled under and around.
Essential qualities
Cool, dry, and well-ventilated.
Usually on the shady side of the house.
No fireplaces or hot flues in any of the adjoining walls.
Might have a door to an outside yard.
Had windows with wire gauze in them instead of glass.
Description
In the northern hemisphere, most houses would be arranged to have their larders and kitchens on the north or west side of the house where they received the least amount of sun. In Australia and New Zealand, larders were placed on the south or east sides of the house for the same reason.
Many larders have small, unglazed windows with window openings covered in fine mesh. This allows free circulation of air without allowing flies to enter. Many larders also have tiled or painted walls to simplify cleaning. Older larders, and especially those in larger houses, have hooks in the ceiling to hang joints of meat.
A pantry may contain a thrawl, a term used in Derbyshire and Yorkshire to denote a stone slab or shelf used to keep food cool in the days before refrigeration was domestically available. In a late medieval hall, a thrawl would have been equivalent to a larder. In a large or moderately large 19th-century house, all these rooms would have been placed in the lowest, and/or as convenient, coolest possible location in the building to use the mass of the groun |
https://en.wikipedia.org/wiki/Pulse%20duration | In signal processing and telecommunication, pulse duration is the interval between the time, during the first transition, that the amplitude of the pulse reaches a specified fraction (level) of its final amplitude, and the time the pulse amplitude drops, on the last transition, to the same level.
The interval between the 50% points of the final amplitude is usually used to determine or define pulse duration, and this is understood to be the case unless otherwise specified. Other fractions of the final amplitude, e.g., 90% or 1/e, may also be used, as may the root mean square (rms) value of the pulse amplitude.
In radar, the pulse duration is the time the radar's transmitter is energized during each cycle. |
https://en.wikipedia.org/wiki/Lumbocostal%20triangle | The lumbocostal triangle (also Bochdalek's foramen, Bochdalek's triangle) is a space between the costal and lumbar parts of the diaphragm. The base of this triangular space is formed by muscle attachments originating from the XII rib and muscle fibers attaching to the lateral arcuate ligament. The apex of the triangle is oriented towards the tendinous centre of the diaphragm. Parietal pleura and renal capsule are in contact in this space, so possible infection can be transmitted through this space.
Clinical significance
The existence of this foramen might cause a congenital diaphragmatic hernia, Bochdalek hernia.
This condition has also been associated with thoracic kidney, the presence of the kidney in the thorax instead of the usual abdominal position. |
https://en.wikipedia.org/wiki/Jakob%20von%20Uexk%C3%BCll%20Centre | Jakob von Uexküll Centre is an Estonia-based organisation for the work with the legacy of biologist, philosopher and semiotician Jakob von Uexküll. The Centre owns the major archive of his works in the world.
The Centre was established in 1993. It is situated in Tartu and attached to the Estonian Naturalists' Society. The Centre co-works with the Department of Semiotics of the University of Tartu.
The Centre has an archive with a rich collection of Jakob von Uexküll's publications, correspondence, manuscripts, photos and other materials.
The Centre has organised some important conferences on biosemiotics and ecosemiotics. It is also a co-organiser of the series of Jakob von Uexküll lectures.
The Centre's Heads have been Toomas Trapido, Timo Maran, Riin Magnus, and others.
See also
Spring school on theoretical biology |
https://en.wikipedia.org/wiki/Bond-out%20processor | A bond-out processor is an emulation processor that takes the place of the microcontroller or microprocessor in the target board while an application is being developed and/or debugged.
Bond-out processors have internal signals and bus brought out to external pins. The term bond-out derives from connecting (or bonding) the emulation circuitry to these external pins. These devices are designed to be used within an in-circuit emulator and are not typically used in any other kind of system.
Bond-out pins were marked as no-connects in the first devices produced by Intel, and were usually not connected to anything on the ordinary production silicon. Later bond-out versions of the microprocessor were produced in a bigger package to provide more signals and functionality.
Bond-out processors provides capabilities far beyond those of a simple ROM monitor. A ROM monitor is a firmware program that runs instead of the application code and provides a connection to a host computer to carry out debugging functions. In general the ROM monitor uses part of the processor resources and shares the memory with the user code.
Bond-out processors can handle complex breakpoints (even in ROM), real-time traces of processor activity, and no use of target resources. But this extra functionality comes at a high cost, as bond-outs have to be produced for in-circuit emulators only.
Therefore, sometimes solutions similar to bond-outs are implemented with an ASIC or FPGA or a faster RISC processor that imitates the core processor code execution and peripherals. |
https://en.wikipedia.org/wiki/Greibach%20normal%20form | In formal language theory, a context-free grammar is in Greibach normal form (GNF) if the right-hand sides of all production rules start with a terminal symbol, optionally followed by some variables. A non-strict form allows one exception to this format restriction for allowing the empty word (epsilon, ε) to be a member of the described language. The normal form was established by Sheila Greibach and it bears her name.
More precisely, a context-free grammar is in Greibach normal form, if all production rules are of the form:
where is a nonterminal symbol, is a terminal symbol,
is a (possibly empty) sequence of nonterminal symbols not including the start symbol and is the start symbol.
Observe that the grammar does not have left recursions.
Every context-free grammar can be transformed into an equivalent grammar in Greibach normal form. Various constructions exist. Some do not permit the second form of rule and cannot transform context-free grammars that can generate the empty word. For one such construction the size of the constructed grammar is O(4) in the general case and O(3) if no derivation of the original grammar consists of a single nonterminal symbol, where is the size of the original grammar. This conversion can be used to prove that every context-free language can be accepted by a real-time (non-deterministic) pushdown automaton, i.e., the automaton reads a letter from its input every step.
Given a grammar in GNF and a derivable string in the grammar with length , any top-down parser will halt at depth .
See also
Backus–Naur form
Chomsky normal form
Kuroda normal form |
https://en.wikipedia.org/wiki/Remote%20control%20locomotive | A remote control locomotive (also called an RCL) is a railway locomotive that can be operated with a remote control. It differs from a conventional locomotive in that a remote control system has been installed in one or more locomotives within the consist, which uses either a mechanical or radio transmitter and receiver system. The locomotive is operated by a person not physically at the controls within the locomotive cab. They have been in use for many years in the railroad industry, including industrial applications such as bulk material load-out, manufacturing, process and industrial switching. The systems are designed to be fail-safe so that if communication is lost the locomotive is brought to a stop automatically.
History
United Kingdom
One of the earliest remote control locomotives was the GWR Autocoach, which replaced the GWR steam rail motors on both operational cost and maintenance grounds. When running 'autocoach first', the regulator is operated by a linkage to a rotating shaft running the length of the locomotive, passing below the cab floor. This engages (via a telescopic coupling) with another shaft running the full length below the floor of the autocoach. This shaft is turned by a second regulator lever in the cab of the autocoach. The driver can operate the regulator, brakes and whistle from the far (cab) end of the autocoach; the fireman remains on the locomotive and (in addition to firing) also controls the valve gear settings. The driver can also warn of the train's approach using a large mechanical gong, prominently mounted high on the cab end of the autocoach, which is operated by stamping on a pedal on the floor of the cab. The driver, guard and fireman communicate with each other by an electric bell system.
North America
In North America remote controlled locomotives have been in use since the 1980s. In 1988, the US Occupational Safety and Health Administration issued a hazard information bulletin regarding their use. By 1999 Canadian Nat |
https://en.wikipedia.org/wiki/Tr%E1%BA%A7n%20Ng%E1%BB%8Dc%20Ch%C3%A2u | Tran Ngoc Châu (1 January 1924 – 17 June 2020) was a Vietnamese soldier (Lieutenant Colonel), civil administrator (city mayor, province chief), politician (leader of the Lower House of the National Assembly), and later political prisoner, in the Republic of Vietnam until its demise with the Fall of Saigon in 1975. There are published photographs of Châu taken c.1952 and 1969, and others in his memoirs, Vietnam Labyrinth.
Much earlier in 1944, he had joined the Việt Minh to fight for independence from the French. Yet as a Vietnamese Buddhist by 1949 he had decisively turned against Communism in Vietnam. He then joined new nationalist forces led by the French. When Vietnam was divided in 1954, he became an officer in the Army of the Republic of Vietnam (ARVN).
For many years he worked on assignments directly under President Ngô Đình Diệm (1954–1963). He became the mayor of Da Nang, and was later a province chief in the Mekong Delta. In particular, Châu became known for his innovative approaches to the theory and practice of counter-insurgency: the provision of security ("pacification") to civilian populations during the Vietnam War. The ultimate government goal of winning the hearts and minds of the people eventually led him to enter politics.
In 1967, after resigning from the ARVN Châu was elected to the newly formed National Assembly in Saigon. He became a legislative leader. Along with others, however, he failed to persuade his old friend Nguyễn Văn Thiệu, the former general who had become President (1967–1975), to turn toward a negotiated peace. Hence Châu associated with Assembly groups in opposition to the prevailing war policies and the ubiquitous corruption.
Under the pretext that he spoke to his communist brother, Châu was accused of treason in 1970, during a major government crackdown on dissidents. Among others, Daniel Ellsberg spoke on his behalf before the United States Congress. Amid sharp controversy in South Vietnam, widely reported in the internat |
https://en.wikipedia.org/wiki/GABRR1 | Gamma-aminobutyric acid receptor subunit rho-1 is a protein that in humans is encoded by the GABRR1 gene.
GABA is the major inhibitory neurotransmitter in the mammalian brain where it acts at GABA receptors, which are ligand-gated chloride channels. GABRR1 is a member of the rho subunit family.
See also
GABAA-ρ receptor |
https://en.wikipedia.org/wiki/AudioMulch | AudioMulch is modular audio software for making music and processing sound. The software can synthesize sound and process live and pre-recorded sound in real-time.
AudioMulch has a patcher-style graphical user interface, in which modules called contraptions can be connected together to route audio and process sounds. Included are modules used in electronic dance music such as a bassline-style synthesizer and a drum machine, effects like ring modulation, flanging, reverb and delays, and other modules such as a delay-line granulator and stereo spatializer. As well as these internal contraptions, AudioMulch supports VST and VSTi plugins.
History
Origins of AudioMulch
AudioMulch grew out of musician Ross Bencina's performance practice in the mid-1990s. At this time, live, computer-based sound processing systems were often expensive and restricted to use within research institutions. By 1995 however, the processing capabilities of the personal computer were sufficient that Bencina was able to create OverSYTE, a real-time performance granulator. OverSYTE was used by Bencina to process sound in his real-time performances with vocalists and instrumental musicians. AudioMulch grew out of the limitations of OverSYTE, which could process only one sound at a time. In contrast, AudioMulch can process multiple sounds sources at once.
Development of AudioMulch
AudioMulch has been in development since 1997. The first release made available for download on the Internet was beta version 0.7b1, in March 1998. There were 36 Beta releases prior to Version 1.0 of the software, which was released in February 2006.
AudioMulch 1.0 was developed for Microsoft Windows in the C++ programming language, using the Borland C++ Builder development environment.
Version 1.0
Version 1.0 was released on 21 February 2006.
Version 2.0
AudioMulch 2.0 was released 5 June 2009. According to the website, this version is available for both Windows and Macintosh computers.
Version 2.1
Version 2.1 |
https://en.wikipedia.org/wiki/Server%20Technology | Server Technology, Inc. offers power distribution products for data centers, telecommunication equipment and remote administration. The company is headquartered in Reno, Nevada with offices in the United Kingdom, Germany, Hong Kong and India.
History
Server Technology was founded in 1984, and by 1987 had grown large enough to acquire CrossPoint Systems, a manufacturer of PC data switches. In 1990, Server Technology introduced its first power and network control products.
Server Technology currently has 170+ employees with 16 offices worldwide.
In 2017 Legrand acquired Server Technology.
Patents
Server Technology claims to have the largest patent library regarding power provision in zero-U and horizontal power distribution unit (PDU) configurations compatible with today's racks and dense computing infrastructure requirements. The company has been granted at least 48 patents and has at least 54 pending.
In June 2014, a Reno, Nevada jury awarded Server Technology, Inc. damages totaling $10,787,634 in an action for patent infringement brought against American Power Conversion Corporation (“APC”), a subsidiary of Schneider Electric SA (Euronext: SU). The Server Technology patents in suit are US Patent No. 7,043,543 (Vertical‐Mount Electrical Power Distribution Plugstrip) issued May 9, 2006, and US Patent No. 7,702,771 (Electrical Power Distribution Device Having A Current Display) issued April 20, 2010.
This finding was overturned in the US Federal Court of Appeals in September 2016.
The complaint was filed in United States District Court for the Northern District of Nevada in December 2006. In February 2007, APC was acquired by Schneider Electric SA (Euronext: SU) headquartered in Rueil‐Malmaison, France. The jury found APC's AP7900 series and AP8900 series vertical, switched Power Distribution Units infringed both of the Server Technology patents.
On September 23, 2016, The US Federal Circuit Court of Appeals reversed the June 2014 Award and found that APC/Sch |
https://en.wikipedia.org/wiki/Hunza%20diet | The Hunza cuisine also called the Burusho cuisine () consists of a series of selective food and drink intake practiced by the Burusho people (also called the Hunza people) of northern Pakistan. Alternative medicine and natural health advocates have argued without providing any scientific evidence that the Hunza diet can increase longevity to 120 years. The diet mostly consists of raw food including nuts, fresh vegetables, dry vegetables, mint, fruits and seeds added with yogurt. The cooked meal, daal included with chappati, is included for dinner.
Longevity myth
In the 1930s, Swiss-German physician Ralph Bircher conducted research on the Hunza diet. In his book about the Hunza, Jay Hoffman argued that, by the ratio to cats, dogs and horses, humans should live up to 120 to 150 years, and argues the Hunza diet to be the key to this longevity. Such ideas also promoted by natural health advocates have been discredited. There is no reliable documentation validating the age of alleged Hunza supercentenarians.
In 2005, the Encyclopedia of World Geography stated that "to date there is no credible evidence that determines that the Hunzakut diet of old, not to mention the current diet of the past four decades, contributes to longevity."
Another myth associated with the Hunza people is that because their diet is alleged to be high in apricot seeds they are free from disease. This has proven to be untrue as medical scientists have found that the Hunzas suffer from a variety of disease including cancer.
See also
Longevity myths
Pakistani cuisine |
https://en.wikipedia.org/wiki/Migration%20%28virtualization%29 | In the context of virtualization, where a guest simulation of an entire computer is actually merely a software virtual machine (VM) running on a host computer under a hypervisor, migration (also known as teleportation, also known as live migration) is the process by which a running virtual machine is moved from one physical host to another, with little or no disruption in service.
Subjective effects
Ideally, the process is completely transparent, resulting in no disruption of service (or downtime). In practice, there is always some minor pause in availability, though it may be low enough that only hard real-time systems are affected. Virtualization is far more frequently used with network services and user applications, and these can generally tolerate the brief delays which may be involved. The perceived impact, if any, is similar to a longer-than-usual kernel delay.
Objective effects
The actual process is heavily dependent on the particular virtualization package in use, but in general, the process is as follows:
Regular snapshots of the VM (its simulated hard disk storage, its memory, and its virtual peripherals) are taken in the background by the hypervisor, or by a set of administrative scripts.
Each new snapshot adds a differential overlay file to the top of a stack that, as a whole, fully describes the machine. Only the topmost overlay can be written to.
Since the older overlays are read-only, they are safe to copy to another machine—the backup host. This is done at regular intervals, and each overlay need only be copied once.
When a migration operation is requested, the virtual machine is paused, and its current state is saved to disk.
These new, final overlay files are transferred to the backup host.
Since this new current state consists only of changes made since the last backup synchronization, for many applications there is very little to transfer, and this happens very quickly.
The hypervisor on the new host resumes the guest virtual machine.
Id |
https://en.wikipedia.org/wiki/Christmas%20Bird%20Count | The Christmas Bird Count (CBC) is a census of birds in the Western Hemisphere, performed annually in the early Northern-hemisphere winter by volunteer birdwatchers and administered by the National Audubon Society. The purpose is to provide population data for use in science, especially conservation biology, though many people participate for recreation. The CBC is the longest-running citizen science survey in the world.
History
Up through the 19th century, many North Americans participated in the tradition of Christmas "side hunts", in which they competed at how many birds they could kill, regardless of whether they had any use for the carcasses and of whether the birds were beneficial, beautiful, or rare. In December 1900, the U.S. ornithologist Frank Chapman, founder of Bird-Lore (which became Audubon magazine), proposed counting birds on Christmas instead of killing them.
On Christmas Day of that year, 27 observers took part in the first count in 25 places in the United States and Canada, the count totaling 18,500 individual birds belonging to 90 species. Since then the counts have been held every winter, usually with increasing numbers of observers. For instance, the 101st count, in the winter of 2000–2001, involved 52,471 people in 1,823 places in 17 countries (but mostly in the U.S. and Canada). During the 113th count (winter 2012–2013), 71,531 people participated in 2,369 locations. The National Audubon Society now partners with Bird Studies Canada, the Gulf Coast Bird Observatory of Texas (responsible for CBCs in Mexico), and the Red Nacional de Observadores de Aves (RNOA, National Network of Bird Observers) and the Instituto Alexander von Humboldt of Colombia.
The greatest number of bird species ever reported by any U.S. location in a single count is 250, observed on December 19, 2005, in the Matagorda County-Mad Island Marsh count circle around Matagorda and Palacios, Texas. The greatest number of bird species ever reported by a CBC circle in the worl |
https://en.wikipedia.org/wiki/Methyldichlorophosphine | Methyldichlorophosphine (alternatively known as dichloro(methyl)phosphane and methyl phosphonous dichloride) is an organophosphorus compound with the chemical formula CH3PCl2. It is a colorless, corrosive, flammable, and highly reactive liquid with a pungent odor.
Preparation
Methyldichlorophosphine is produced by alkylation of phosphorus trichloride with methyl iodide followed by reduction of the resulting phosphonium salt with iron powder: The compound is an intermediate for the synthesis of other chemicals for instance dimethylphenylphosphine:
CH3I + PCl3 + AlCl3 → [CH3PCl3]+AlCl3I−
[CH3PCl3]+AlCl3I− + Fe → CH3PCl2 + FeClI + AlCl3
Uses
Methyldichlorophosphine belongs to the group of halophosphines, some of which are used as intermediates in the production of plant protection agents, stabilizers for plastics, and catalysts. It is a precursor of the herbicide Glufosinate. It is also used in the production of flameproofing compounds.
Due to the recycling problem of phosphoryl chloride, SW was adopted in step three of the DMHP process in the preparation of GB. SW was also adopted as a standard precursor to V agents, having been used to prepare QL for unitary and binary VX. SW was the first agent adopted to prepare VX in one pot reaction by aqueous medium.
Safety
It is also toxic if inhaled, can cause burns upon contact with the skin and eyes, and releases fumes of hydrochloric acid in moist environments. |
https://en.wikipedia.org/wiki/List%20of%20works%20by%20Nikolay%20Bogolyubov | List of some published works of Nikolay Bogolyubov in chronological order:
1924
N. N. Bogolyubov (1924). On the behavior of solutions of linear differential equations at infinity ().
1934
1937
N. N. Bogoliubov and N. M. Krylov (1937). "La theorie generalie de la mesure dans son application a l'etude de systemes dynamiques de la mecanique non-lineaire" (in French). Ann. Math. II 38: 65–113. Zbl. 16.86.
1945
1946
N. N. Bogoliubov (1946). "Kinetic Equations" (in Russian). Journal of Experimental and Theoretical Physics 16 (8): 691–702.
N. N. Bogoliubov (1946). "Kinetic Equations" (in English). Journal of Physics 10 (3): 265–274.
1947
N. N. Bogoliubov, K. P. Gurov (1947). "Kinetic Equations in Quantum Mechanics" (in Russian). Journal of Experimental and Theoretical Physics 17 (7): 614–628.
N. N. Bogoliubov (1947). "К теории сверхтекучести" (in Russian). Известия АН СССР, физика, 1947, 11, № 1, 77.
N. N. Bogoliubov (1947). "On the Theory of Superfluidity" (in English). Journal of Physics 11 (1): 23–32.
1948
N. N. Bogoliubov (1948). "Equations of Hydrodynamics in Statistical Mechanics" (in Ukrainian). Sbornik Trudov Instituta Matematiki AN USSR 10: 41—59.
1949
N. N. Bogoliubov (1967—1970): Lectures on Quantum Statistics. Problems of Statistical Mechanics of Quantum Systems. New York, Gordon and Breach.
1955
1957
(1st edition)
(3rd edition)
N. N. Bogoliubov, O. S. Parasyuk (1957). "Uber die Multiplikation der Kausalfunktionen in der Quantentheorie der Felder" (in German). Acta Mathematica 97: 227–266. .
1958
N. N. Bogoliubov (1958). On a New Method in the Theory of Superconductivity. Journal of Experimental and Theoretical Physics 34 (1): 58.
1965
N. N. Bogolubov, B. V. Struminsky, A. N. Tavkhelidze (1965). On composite models in the theory of elementary particles. JINR Preprint D-1968, Dubna.
External links
Complete list
Mathematics-related lists
Bibliographies by writer |
https://en.wikipedia.org/wiki/Worksheet | A worksheet, in the word's original meaning, is a sheet of paper on which one performs work. They come in many forms, most commonly associated with children's school work assignments, tax forms, and accounting or other business environments. Software is increasingly taking over the paper-based worksheet.
It can be a printed page that a child completes with a writing instrument. No other materials are needed. It is "a sheet of paper on which work schedules, working time, special instructions, etc. are recorded. A piece or scrap of paper on which problems, ideas, or the like, are set down in tentative form." In education, a worksheet may have questions for students and places to record answers.
In accounting, a worksheet is, or was, a sheet of ruled paper with rows and columns on which an accountant could record information or perform calculations. These are often called columnar pads, and typically green-tinted.
In computing, spreadsheet software presents, on a computer monitor, a user interface that resembles one or more paper accounting worksheets. Microsoft Excel, a popular spreadsheet program, refers to a single spreadsheet (more technically, a two-dimensional matrix or array) as a worksheet, and it refers to a collection of worksheets as a workbook.
Education
In the classroom setting, worksheets usually refer to a loose sheet of paper with questions or exercises for students to complete and record answers. They are used, to some degree, in most subjects, and have widespread use in the math curriculum where there are two major types. The first type of math worksheet contains a collection of similar math problems or exercises. These are intended to help a student become proficient in a particular mathematical skill that was taught to them in class. They are commonly given to students as homework. The second type of math worksheet is intended to introduce new topics, and are often completed in the classroom. They are made up of a progressive set of question |
https://en.wikipedia.org/wiki/Borel%20graph%20theorem | In functional analysis, the Borel graph theorem is generalization of the closed graph theorem that was proven by L. Schwartz.
The Borel graph theorem shows that the closed graph theorem is valid for linear maps defined on and valued in most spaces encountered in analysis.
Statement
A topological space is called a Polish space if it is a separable complete metrizable space and that a Souslin space is the continuous image of a Polish space. The weak dual of a separable Fréchet space and the strong dual of a separable Fréchet–Montel space are Souslin spaces. Also, the space of distributions and all Lp-spaces over open subsets of Euclidean space as well as many other spaces that occur in analysis are Souslin spaces. The Borel graph theorem states:
Let and be Hausdorff locally convex spaces and let be linear. If is the inductive limit of an arbitrary family of Banach spaces, if is a Souslin space, and if the graph of is a Borel set in then is continuous.
Generalization
An improvement upon this theorem, proved by A. Martineau, uses K-analytic spaces. A topological space is called a if it is the countable intersection of countable unions of compact sets. A Hausdorff topological space is called if it is the continuous image of a space (that is, if there is a space and a continuous map of onto ). Every compact set is K-analytic so that there are non-separable K-analytic spaces.
Also, every Polish, Souslin, and reflexive Fréchet space is K-analytic as is the weak dual of a Fréchet space. The generalized theorem states:
Let and be locally convex Hausdorff spaces and let be linear. If is the inductive limit of an arbitrary family of Banach spaces, if is a K-analytic space, and if the graph of is closed in then is continuous.
See also |
https://en.wikipedia.org/wiki/Chebyshev%E2%80%93Markov%E2%80%93Stieltjes%20inequalities | In mathematical analysis, the Chebyshev–Markov–Stieltjes inequalities are inequalities related to the problem of moments that were formulated in the 1880s by Pafnuty Chebyshev and proved independently by Andrey Markov and (somewhat later) by Thomas Jan Stieltjes. Informally, they provide sharp bounds on a measure from above and from below in terms of its first moments.
Formulation
Given m0,...,m2m-1 ∈ R, consider the collection C of measures μ on R such that
for k = 0,1,...,2m − 1 (and in particular the integral is defined and finite).
Let P0,P1, ...,Pm be the first m + 1 orthogonal polynomials with respect to μ ∈ C, and let ξ1,...ξm be the zeros of Pm. It is not hard to see that the polynomials P0,P1, ...,Pm-1 and the numbers ξ1,...ξm are the same for every μ ∈ C, and therefore are determined uniquely by m0,...,m2m-1.
Denote
.
Theorem For j = 1,2,...,m, and any μ ∈ C, |
https://en.wikipedia.org/wiki/Chuckie%20Egg | Chuckie Egg is a video game released by A&F Software in 1983 initially for the ZX Spectrum, BBC Micro, and Dragon 32/64. It was ported to the Commodore 64, Acorn Electron, MSX, Tatung Einstein, Amstrad CPC, and Atari 8-bit family. It was later updated for the Amiga, Atari ST, and IBM PC compatibles.
The game was written by Nigel Alderton, then 16 or 17 years old. After a month or two of development, Nigel took a pre-release version of his Spectrum code to the two-year-old software company A&F, co-founded by Doug Anderson and Mike Fitzgerald (the "A" and "F", respectively). Doug took on the simultaneous development of the BBC Micro version, whilst Mike Webb, an A&F employee, completed the Dragon port.
The versions fall broadly into two groups: those with realistic physics (e.g., BBC Micro and Amstrad CPC) and those without (e.g., ZX Spectrum). Although there is a substantial difference in play between the two, levels remain largely the same and all the 8-bit versions have been cited as classics.
Gameplay
As Hen-House Harry, the player must collect the twelve eggs positioned in each level, before a countdown timer reaches zero. In addition there are piles of seed which may be collected to increase points and stop the countdown timer for a while, but will otherwise be eaten by hens that patrol the level, causing them to pause. If the player touches a hen or falls through a gap in the bottom of the level, they lose a life. Each level is made of solid platforms, ladders, and occasionally lift platforms that move upwards and when they reach the top of the screen wrap around to the bottom. Hitting the top of the screen while on one of these lifts, however, will also cause the player to lose a life.
Eight levels are defined and are played initially under the watch of a giant caged duck. Upon completion of all eight the levels are played again without hens, but Harry is now pursued by the freed duck flying around the screen and homing in on him. A second completion of |
https://en.wikipedia.org/wiki/Feature%20creep | Feature creep is the excessive ongoing expansion or addition of new features in a product, especially in computer software, video games and consumer and business electronics. These extra features go beyond the basic function of the product and can result in software bloat and over-complication, rather than simple design.
The definition of what qualifies as "feature creep" varies among end users, where what is perceived as such by some users may be considered practical functionality by others. Feature creep is one of the most common sources of cost and schedule overruns. It thus endangers and can even kill products and projects.
Causes
Feature creep may arise from the desire to provide the consumer with a more useful or desirable product in order to increase sales or distribution. Once a product does everything that it is designed to do, the manufacturer may add functions some users might consider unneeded (sometimes at the cost of efficiency) or continue with the original version (at the cost of a perceived lack of improvement).
Feature creep may also arise as a result of compromise from a committee implementing several different viewpoints or use cases in the same product, even for opportunistic reasons. As more features are added to support each approach, cross-conversion features between the multiple paradigms may further complicate the total features.
Control
There are several methods to control feature creep, including: strict limits for allowable features, multiple variations, and pruning excess features.
Separation
Later feature creep may be avoided by basing initial design on strong software fundamentals, such as logical separation of functionality and data access, e.g. using submenus that are optionally accessible by power users who desire more functionality and a higher verbosity of information. It can be actively controlled with rigorous change management and by delaying changes to later delivery phases of a project.
Variations and options
Anothe |
https://en.wikipedia.org/wiki/Swisscom | Swisscom AG is a major telecommunications provider in Switzerland. Its headquarters are located in Worblaufen near Bern. The Swiss government owns 51 percent of Swisscom AG. According to its own published data, Swisscom holds a market share of 56% for mobile, 50% for broadband and 37% for TV telecommunication in Switzerland. Its Italian subsidiary Fastweb is attributed 16% of private clients and 29% of corporate clients share of Italian broadband and is also active in the mobile market.
The Swiss telegraph network was first set up in 1852, followed by telephones in 1877. The two networks were combined with the postal service in 1920 to form Postal Telegraph and Telephone (PTT). The Swiss telecommunications market was deregulated in 1997. Telecom PTT was spun off and rebranded Swisscom ahead of a partial privatisation in 1997. The present-day Swisscom owns the protected brand NATEL, which is used and known only in Switzerland.
In 2001, 25% of Swisscom Mobile was sold to Vodafone. In 2007, Swisscom acquired a majority stake in Italy's second-biggest telecom company Fastweb.
History
Pioneers (1852–1911)
Switzerland's entry into the telecommunications era came in 1851, with the passage of legislation giving the Swiss government control over the development of a telegraph network throughout the country. The government's initial plans called for the creation of three primary telegraph lines, as well as a number of secondary networks. In order to build equipment for the system, the government established the Atelier Fédéral de Construction des Télégraphes (Federal Workshop for the Construction of Telegraphs).
In July 1852, the first leg of the country's telegraph system—between St. Gallen and Zurich—was operational. By the end of that year, most of the country's main cities had been connected to the telegraph system. In 1855, the network was extended with the first underwater cable, connecting Winkel-Stansstad and Bauen-Flüelen. Night service was also launched that ye |
https://en.wikipedia.org/wiki/162nd%20meridian%20west | The meridian 162° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 162nd meridian west forms a great circle with the 18th meridian east.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 162nd meridian west passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="130" | Co-ordinates
! scope="col" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Chukchi Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Alaska
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Chukchi Sea
| style="background:#b0e0e6;" | Hotham Inlet
|-
|
! scope="row" |
| Alaska — Baldwin Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Chukchi Sea
| style="background:#b0e0e6;" | Kotzebue Sound
|-
|
! scope="row" |
| Alaska — Seward Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Norton Sound
|-
|
! scope="row" |
| Alaska
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Kuskokwim Bay
|-
|
! scope="row" |
| Alaska
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Kuskokwim Bay
|-
|
! scope="row" |
| Alaska — Cape Newenham
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Bristol Bay
|-
|
! scope="row" |
| Alaska — Alaska Peninsula
|-valign="top"
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e |
https://en.wikipedia.org/wiki/Immunization | Immunization, or immunisation, is the process by which an individual's immune system becomes fortified against an infectious agent (known as the immunogen).
When this system is exposed to molecules that are foreign to the body, called non-self, it will orchestrate an immune response, and it will also develop the ability to quickly respond to a subsequent encounter because of immunological memory. This is a function of the adaptive immune system. Therefore, by exposing a human, or an animal, to an immunogen in a controlled way, its body can learn to protect itself: this is called active immunization.
The most important elements of the immune system that are improved by immunization are the T cells, B cells, and the antibodies B cells produce. Memory B cells and memory T cells are responsible for a swift response to a second encounter with a foreign molecule. Passive immunization is direct introduction of these elements into the body, instead of production of these elements by the body itself.
Immunization happens in various ways, both in the wild and as done by human efforts in health care. Natural immunity is gained by those organisms whose immune systems succeed in fighting off a previous infection, if the relevant pathogen is one for which immunization is even possible. Natural immunity can have degrees of effectiveness (partial rather than absolute) and may fade over time (within months, years, or decades, depending on the pathogen). In health care, the main technique of artificial induction of immunity is vaccination, which is a major form of prevention of disease, whether by prevention of infection (pathogen fails to mount sufficient reproduction in the host), prevention of severe disease (infection still happens but is not severe), or both. Vaccination against vaccine-preventable diseases is a major relief of disease burden even though it usually cannot eradicate a disease. Vaccines against microorganisms that cause diseases can prepare the body's immune sy |
https://en.wikipedia.org/wiki/Summermatter%20cycle | The Summermatter cycle is a physiological concept describing the complex relationship between physical activity/inactivity and energy expenditure/conservation.
The concept explains why dieting fails in most cases and results in a Yo-yo effect. A central element of the Summermatter cycle is that reductions in energy intake, occurring with dieting or starvation, initially successfully induce weight and adipose tissue loss. At the same time, the reduced food availability prompts ambulatory activity, which further accelerates body and fat mass loss and depletes ATP, glycogen and intramyocellular lipids (IMCL) in skeletal muscle. The scarcity of energy ultimately suppresses thermogenesis in skeletal muscle to conserve energy.
As soon as energy becomes available again, this originally adaptive, thrifty program supports the replenishment of energy stores and weight regain. Fat deposition is the most efficient way for the body to store energy. This phenomenon of energy store replenishment is driven by a hyperinsulinemic state and is referred to as preferential catch-up fat. Satiety signals during the period of food availability automatically lead to rest, which further supports adipose tissue regain and the restoration of glycogen and IMCL pools in muscle. As a result, the majority of people rapidly regain body weight. Exercise increases energy expenditure and can counteract the suppression of thermogenesis in skeletal muscle thereby preventing weight regain. In addition, regular exercise promotes the turnover of ATP, glycogen and IMCLs.
The hypothesis was put forward in 2012 and Benton, et al. named the cycle in 2017 after his inventor, the Swiss biochemist, nutritionist and exercise physiologist Dr. Serge Summermatter.
The concept of the Summermatter cycle finds broad application in body weight management to time exercise interventions and avoid catch-up fat (yo-yo effect). Moreover, the concept is used by elite athletes to optimally coordinate their exercise and en |
https://en.wikipedia.org/wiki/Virtual%20Distributed%20Ethernet | Virtual Distributed Ethernet (VDE) is a set of programs to provide virtual software-defined Ethernet network interface controllers (NICs) across multiple devices, typically computers, which are either virtual or physical. It forms part of the Virtual Square project from the Italian Bologna University whose code is available on public servers using free software licenses, mostly GPLv2. Researchers at the Department of Mathematics and Computer Science, Xavier University, Cincinnati OH, US are also working on the project.
It is one of the available networking methods for the Linux Kernel-based Virtual Machine (KVM) and forms part of some Linux distributions such as Ubuntu Precise (12.04 LTS) and Debian
Overview
Software-defined networking is the dynamic creation of virtual network infrastructure that is completely decoupled and independent of any physical network hardware.
Structure
VDE (Virtual Distributed Ethernet) comprises 5 main components:
VDE switch
A virtual ethernet switch is equivalent of a physical switch with multiple virtual ports supporting connections from VDE devices. Supports telnet and a web interface for monitoring and configuration.
VDE plug
Simulates a plug on the end of a physical ethernet cable such as the 8P8C. It forms the connection point between the host and the virtual VDE wire.
VDE wire
Receives the data from a VDE plug and transports it to another VDE plug. Obviously performing the same function as the wires within normal ethernet cabling.
VDE cable
The combination of 2 VDE plugs and 1 VDE wire is called a VDE cable.
VDE cryptcab
A connectionless protocol that encrypts the data before transmitting it and that decrypts the data on the other side. Informally known as VDE Encrypted Cable. |
https://en.wikipedia.org/wiki/Einstein%E2%80%93Brillouin%E2%80%93Keller%20method | The Einstein–Brillouin–Keller method (EBK) is a semiclassical method (named after Albert Einstein, Léon Brillouin, and Joseph B. Keller) used to compute eigenvalues in quantum-mechanical systems. EBK quantization is an improvement from Bohr-Sommerfeld quantization which did not consider the caustic phase jumps at classical turning points. This procedure is able to reproduce exactly the spectrum of the 3D harmonic oscillator, particle in a box, and even the relativistic fine structure of the hydrogen atom.
In 1976–1977, Michael Berry and M. Tabor derived an extension to Gutzwiller trace formula for the density of states of an integrable system starting from EBK quantization.
There have been a number of recent results on computational issues related to this topic, for example, the work of Eric J. Heller and Emmanuel David Tannenbaum using a partial differential equation gradient descent approach.
Procedure
Given a separable classical system defined by coordinates , in which every pair describes a closed function or a periodic function in , the EBK procedure involves quantizing the line integrals of over the closed orbit of :
where is the action-angle coordinate, is a positive integer, and and are Maslov indexes. corresponds to the number of classical turning points in the trajectory of (Dirichlet boundary condition), and corresponds to the number of reflections with a hard wall (Neumann boundary condition).
Examples
1D Harmonic oscillator
The Hamiltonian of a simple harmonic oscillator is given by
where is the linear momentum and the position coordinate. The action variable is given by
where we have used that is the energy and that the closed trajectory is 4 times the trajectory from 0 to the turning point .
The integral turns out to be
,
which under EBK quantization there are two soft turning points in each orbit and . Finally, that yields
,
which is the exact result for quantization of the quantum harmonic oscillator.
2D hydrogen atom
Th |
https://en.wikipedia.org/wiki/Lancet%20Group%20of%20Laboratories | The Lancet Group of Laboratories, also known as Lancet Laboratories, is a private pathology service founded and based in Johannesburg, South Africa.
Structure
The Lancet Group of Laboratories is a private pathology service based in Johannesburg, South Africa. It has over 100 reference laboratories and more than 250 branches in over 14 African countries.
Tests provided include PCR and genetic tests for cancers and infectious diseases, histopathology, cytopathology, immunohistochemistry, testing for tuberculosis, microbiology, endocrinology, clinical chemistry, blood clotting, haematology, toxicology and tests relating to occupations.
South Africa
In 1996 the main laboratory moved to Richmond and could provide services to the Gauteng region. In 2000 it merged with the Pillay MacIntosh practice in Durban.
Eftyhia Vardas is the head of virology at the Lancet in Johannesburg. In November 2021, Alison J. Glass, a clinical virologist at the lab reported that observations made by one of their junior scientists led to the discovery of the omicron variant of the COVID-19 virus. The laboratory sent samples to the Network for Genomic Surveillance in South Africa, of which the Lancet is a part and whose principal investigator, Tulio de Oliveira, confirmed and announced the findings following further investigation.
East Africa
Its East Africa, laboratories include Pathologists Lancet Kenya Limited, established in 2009. Others include Lancet Laboratories Uganda Limited and Lancet Laboratories Tanzania Limited.
West Africa
It has operations in West Africa. |
https://en.wikipedia.org/wiki/Creola%20bodies | Creola bodies are a histopathologic finding indicative of asthma. Found in a patient's sputum, they are ciliated columnar cells sloughed from the bronchial mucosa of a patient with asthma. Other common findings in the sputum of asthma patients include Charcot-Leyden crystals, Curschmann's Spirals, and eosinophils (and excessive amounts of sputum).
Yoshihara et al. reported 60% of pediatric asthmatic patients demonstrating acute symptoms were found to have creola bodies in their sputum. These patients had increased levels of neutrophil-mediated cytokine activity concluding that "epithelial damage is associated with a locally enhanced chemotactic signal for and activity of neutrophils, but not eosinophils, during acute exacerbations of paediatric asthma."
Ogata et al. found significant correlations among the CrB score, the concentration of sputum ECP and %FEV1.0 (p less than 0.001). The CrB score on the day of clinical appraisal significantly correlated with the number 6f days of treatment needed for remission. These results were in keeping with the hypothesis that eosinophils cause desquamation of respiratory epithelial cells resulting in prolongation of asthmatic attacks. Observation of CrB seemed to be useful as a marker of duration of asthmatic attacks. |
https://en.wikipedia.org/wiki/Analysis%20Situs%20%28book%29 | Analysis Situs is a book by the Princeton mathematician Oswald Veblen, published in 1922. It is based on his 1916 lectures at the Cambridge Colloquium of the American Mathematical Society. The book, which went into a second edition in 1931, was the first English-language textbook on topology, and served for many years as the standard reference for the domain. Its contents were based on the work of Henri Poincaré as well as Veblen's own work with his former student and colleague, James Alexander.
Among the many innovations in the book was the first definition of a topological manifold, and systematisations of Betti number, torsion, the fundamental group, and the topological classification problem. |
https://en.wikipedia.org/wiki/3-Methylfentanyl | 3-Methylfentanyl (3-MF, mefentanyl) is an opioid analgesic that is an analog of fentanyl. 3-Methylfentanyl is one of the most potent opioids, estimated to be between 400 and 6000 times stronger than morphine, depending on which isomer is used (with the cis isomers being the more potent ones).
Overview and history
was first discovered in 1974 and subsequently appeared on the street as an alternative to the clandestinely produced fentanyl analog α-methylfentanyl. However, it quickly became apparent that was much more potent than α-methylfentanyl, and correspondingly more dangerous.
While was initially sold on the black market for only a short time between 1984 and 1985, its high potency made it an attractive target to clandestine drug producers, as racemic is 10–15 times more potent than fentanyl, and so correspondingly larger amounts of cut product for street sales can be produced for an equivalent amount of effort as for producing fentanyl itself; one gram of might be sufficient to produce several thousand dosage units once diluted for sale. has thus reappeared several times, at various places around the world.
The only country in the world with significant (200+ deaths a year, more than 10,000 addicts) abuse of this chemical is Estonia, where a dose of costs 10 €, and other opiates are not generally available since the end of the 2000s. Approximately 1100 deaths from fentanyl and abuse were recorded in Estonia between 2005–2013, compared to approximately 450 deaths in Sweden, Germany, UK, Finland and Greece combined during the same period.
Other opioid analogs even more potent still than are known, such as carfentanil and ohmefentanyl, but these are significantly more difficult to manufacture than . Since 2016 fentanyl seizures in Estonia contains mostly carfentanil or cyclopropylfentanyl.
has similar effects to fentanyl, but is far more potent due to increased binding affinity to its target site. Since fentanyl itself is already highly potent, is |
https://en.wikipedia.org/wiki/ACAD9 | Acyl-CoA dehydrogenase family member 9, mitochondrial is an enzyme that in humans is encoded by the ACAD9 gene. Mitochondrial Complex I Deficiency with varying clinical manifestations has been associated with mutations in ACAD9.
Structure
The ACAD9 gene contains an open reading frame of 1866 base pairs; this gene encodes a protein with 621 amino acid residues. Alignment of the ACAD9 protein sequence with that of other human ACAD proteins showed that ACAD-9 protein displays 46–27% identity, and 56–38% similarity with the eight members of the ACAD family, including ACADVL, ACADS, ACADM, ACADL, IVD, GCD, ACADSB, and ACD8. The calculated molecular weight of the ACAD9 is 68.8 kDa.
Function
The ACAD9 enzyme catalyzes a crucial step in fatty acid beta-oxidation by forming a C2-C3 trans-double bond in the fatty acid. LVCAD is specific to very long-chain fatty acids, typically C16-acylCoA and longer. It has been observed that ACAD9 can catalyze acyl-CoAs with very long chains. The specific activity of ACAD9 towards palmitoyl-CoA (C16:0) is three times higher than that towards stearoyl-CoA (C18:0). ACAD-9 has little activity on n-octanoyl-CoA (C8:0), n-butyryl-CoA (C4:0) or isovaleryl-CoA (C5:0).
In contrast with ACADVL, ACAD9 is also involved in assembly of the oxidative phosphorylation complex I. ACAD9 binds complex I assembly factors NDUFAF1 and Ecsit and is specifically required for the assembly of complex I. Furthermore, ACAD9 mutations result in complex I deficiency and not in disturbed long-chain fatty acid oxidation.
Clinical significance
Mutations in the ACAD9 gene are associated with mitochondrial complex I deficiency type 20, which is autosomal recessive. This deficiency is the most common enzymatic defect of the oxidative phosphorylation disorders. Mitochondrial complex I deficiency shows extreme genetic heterogeneity and can be caused by mutation in nuclear-encoded genes or in mitochondrial-encoded genes. There are no obvious genotype–phenotype correlat |
https://en.wikipedia.org/wiki/Mal%20regulon | In bacterial genetics, the mal regulon is a regulon - or group of genes under common regulation - associated with the catabolism of maltose and maltodextrins. The system is especially well characterized in the model organism Escherichia coli, where it is classically described as a group of ten genes in multiple operons whose expression is regulated by a single regulatory protein, malT. MalT binds to maltose or maltodextrin and undergoes a conformational change that allows it to bind DNA at sequences near the promoters of genes required for uptake and catabolism of these sugars. The maltose regulation system in E. coli is a classic example of positive regulation. malT is regulated by catabolite repression via the catabolite activator protein. Genes under the control of malT include ATP-binding cassette transporter components, maltoporin, maltose binding protein, and several enzymes. Other Gram-negative bacteria such as Klebsiella pneumoniae have additional genes under the control of malT.
In many Gram-positive bacteria, such as Streptococcus pneumoniae, maltose catabolism is regulated differently, via a transcriptional repressor called malR, in the lac repressor family. |
https://en.wikipedia.org/wiki/Disease%20informatics | Disease Informatics is the application of Information science by defining the diseases with the least error, identifying most of the targets to combat a cluster of diseases (Disease Causal Chain), and designing a holistic solution (Health strategy) to the problem. |
https://en.wikipedia.org/wiki/Basidiobolomycosis | Basidiobolomycosis is a fungal disease caused by Basidiobolus ranarum. It may appear as one or more painless firm nodules in the skin which becomes purplish with an edge that appears to be slowly growing outwards. A serious but less common type affects the stomach and intestine, which usually presents with abdominal pain, fever and a mass.
B. ranarum, can be found in soil, decaying vegetables and has been isolated from insects, some reptiles, amphibians, and mammals. The disease results from direct entry of the fungus through broken skin such as an insect bite or trauma, or eating contaminated food. It generally affects people who are well.
Diagnosis is by medical imaging, biopsy, microscopy, culture and histopathology. Treatment usually involves amphotericin B and surgery.
Although B. ranarum is found around the world, the disease Basidiobolomycosis is generally reported in tropical and subtropical areas of Africa, South America, Asia and Southwestern United States. It is rare. The first case in a human was reported from Indonesia in 1956 as a skin infection.
Signs and symptoms
Basidiobolomycosis may appear as a firm nodule in the skin which becomes purplish with an edge that appears to be slowly growing outwards. It is generally painless but may feel itchy or burning. There can be one lesion or several, and usually on the arms or legs of children. Pus may be present if a bacterial infection also occurs. The infection can spread to nearby structures such as muscles, bones and lymph nodes.
A serious but less common type affects the stomach and intestine, which usually presents with tummy ache, fever and a lump. Lymphoedema may occur.
Mechanism
Basidiobolomycosis is a type of Entomophthoromycosis, the other being conidiobolomycosis, and is caused by Basidiobolus ranarum, a fungus belonging to the order Entomophthorales. B. ranarum has been found in soil, decaying vegetables and has been isolated from insects some reptiles, amphibians, and mammals. The disease |
https://en.wikipedia.org/wiki/WS-124A%20Flying%20Cloud | Weapon System 124A, given the codename Flying Cloud, was a project of the United States Air Force to use high-altitude balloons to deliver bombs and weapons of mass destruction on enemy targets. Tested in late 1954, the project was found to be unfeasible from the standpoint of accuracy, and the project was terminated the following year.
Design and development
Alongside the WS-119L program to develop long-distance, high-altitude balloons for aerial reconnaissance, the United States Air Force initiated WS-124A in early 1953 to develop a method of delivering weaponry to targets in the Soviet Union using hydrogen balloons; such a capability was considered potentially valuable in the event of a limited nuclear conflict, or in a "broken-back" scenario following a massive nuclear exchange.
The WS-124A balloons were intended to fly at altitudes of roughly , within the jet stream; as weather forecasts were considered to be sufficiently accurate to forecast approximately three days of wind patterns, the design flight duration was for 60 hours, in which they were expected to cover a distance of . The WS-124A balloon was designed to be capable of launching in wind speeds of up to .
It was accepted that there would be an inherent inaccuracy in the concept; the expected target area was by , which was considered acceptable as the designed payloads involved chemical and biological weaponry, although incendiary bombs, for starting forest fires, were also considered as a payload. It was believed that releasing chemical or biological agents from the balloons could contaminate an area "comparable in size to that affected by a low-yield nuclear weapon". Some sources claim that dirty bombs were also considered for carriage by WS-124A. In addition, the ability of the balloons to spread propaganda leaflets across enemy territory was considered useful.
Operational history
Flight tests of the WS-124A balloon system started on 8 October 1954; by 13 December, 41 balloons had been launched |
https://en.wikipedia.org/wiki/Live%20sound%20mixing | Live sound mixing is the blending of multiple sound sources by an audio engineer using a mixing console or software. Sounds that are mixed include those from instruments and voices which are picked up by microphones (for drum kit, lead vocals and acoustic instruments like piano or saxophone and pickups for instruments such as electric bass) and pre-recorded material, such as songs on CD or a digital audio player. Individual sources are typically equalised to adjust the bass and treble response and routed to effect processors to ultimately be amplified and reproduced via a loudspeaker system. The live sound engineer listens and balances the various audio sources in a way that best suits the needs of the event.
Equipment
Audio equipment is usually connected together in a sequence known as the signal chain. In live sound situations, this consists of input transducers like microphones, pickups, and DI boxes. These devices are connected, often via multicore cable, to individual channels of a mixing console. Each channel on a mixing console typically has a vertical "channel strip", which is a column of knobs and buttons which are used to adjust the level and the bass, middle register and treble of the signal. The audio console also typically allows the engineer to add effects units to each channel (addition of reverb, etc.) before they are electrically summed (blended together). A live audio sound mixer basically mixes a bunch of different signals together and then sends that blended signal to outputs (speakers).
EQ mixing involved adjusting each sound source's equalization (EQ) settings to achieve a desired sound. This involves adjusting the frequency, amplitude, and resonance of each sound source. EQ can be used to create clarity and depth to the mix, as well as to customize the sound of each instrument or voice.
Audio signal processing may be applied to (inserted on) individual inputs, groups of inputs, or the entire output mix, using processors that are internal |
https://en.wikipedia.org/wiki/Forbidden%20subgraph%20problem | In extremal graph theory, the forbidden subgraph problem is the following problem: given a graph , find the maximal number of edges an -vertex graph can have such that it does not have a subgraph isomorphic to . In this context, is called a forbidden subgraph.
An equivalent problem is how many edges in an -vertex graph guarantee that it has a subgraph isomorphic to ?
Definitions
The extremal number is the maximum number of edges in an -vertex graph containing no subgraph isomorphic to . is the complete graph on vertices. is the Turán graph: a complete -partite graph on vertices, with vertices distributed between parts as equally as possible. The chromatic number of is the minimum number of colors needed to color the vertices of such that no two adjacent vertices have the same color.
Upper bounds
Turán's theorem
Turán's theorem states that for positive integers satisfying ,
This solves the forbidden subgraph problem for . Equality cases for Turán's theorem come from the Turán graph .
This result can be generalized to arbitrary graphs by considering the chromatic number of . Note that can be colored with colors and thus has no subgraphs with chromatic number greater than . In particular, has no subgraphs isomorphic to . This suggests that the general equality cases for the forbidden subgraph problem may be related to the equality cases for . This intuition turns out to be correct, up to error.
Erdős–Stone theorem
Erdős–Stone theorem states that for all positive integers and all graphs ,
When is not bipartite, this gives us a first-order approximation of .
Bipartite graphs
For bipartite graphs , the Erdős–Stone theorem only tells us that . The forbidden subgraph problem for bipartite graphs is known as the Zarankiewicz problem, and it is unsolved in general.
Progress on the Zarankiewicz problem includes following theorem:
Kővári–Sós–Turán theorem. For every pair of positive integers with , there exists some constant (independent |
https://en.wikipedia.org/wiki/Lowry%20protein%20assay | The Lowry protein assay is a biochemical assay for determining the total level of protein in a solution. The total protein concentration is exhibited by a color change of the sample solution in proportion to protein concentration, which can then be measured using colorimetric techniques. It is named for the biochemist Oliver H. Lowry who developed the reagent in the 1940s. His 1951 paper describing the technique is the most-highly cited paper ever in the scientific literature, cited over 300,000 times.
Mechanism
The method combines the reactions of copper ions with the peptide bonds under alkaline conditions (the Biuret test) with the oxidation of aromatic protein residues. The Lowry method is based on the reaction of Cu+, produced by the oxidation of peptide bonds, with Folin–Ciocalteu reagent (a mixture of phosphotungstic acid and phosphomolybdic acid in the Folin–Ciocalteu reaction). The reaction mechanism is not well understood, but involves reduction of the Folin–Ciocalteu reagent and oxidation of aromatic residues (mainly tryptophan, also tyrosine). Experiments have shown that cysteine is also reactive to the reagent. Therefore, cysteine residues in protein probably also contribute to the absorbance seen in the Lowry assay. The result of this reaction is an intense blue molecule known as heteropolymolybdenum Blue. The concentration of the reduced Folin reagent (heteropolymolybdenum Blue) is measured by absorbance at 660 nm. As a result, the total concentration of protein in the sample can be deduced from the concentration of tryptophan and tyrosine residues that reduce the Folin–Ciocalteu reagent.
The method was first proposed by Lowry in 1951. The bicinchoninic acid assay and the Hartree–Lowry assay are subsequent modifications of the original Lowry procedure.
See also
Biuret test
Bradford protein assay |
https://en.wikipedia.org/wiki/Micropore%20particle%20technology | Micropore particle technology consists of fine, highly porous particles that remove fluid by a combination of capillary action and evaporation. Currently, they are mainly used in wound healing, where they absorb wound exudate into their micropore structure. Here capillary flow transports the exudate away from the wound surface towards the upper surface of the MPPT layer, where a highly expanded surface area facilitates effective evaporation. The MPPT essentially acts as small micro-pumps, which, due to their small size, are able to access all crevices in the wound surface.
The micro-pumping action of the particles appears to disrupt the weaponry used by bacteria and fungi against the immune system. First, the toxins and enzymes released by bacteria and fungi against the immune cells are removed, whereby the immune cells regain their function. Second, the micropumping action creates holes in the surface of biofilm. Biofilm acts as a shield that bacteria and fungi secrete to protect themselves against the immune cells. By creating holes in this shield, the immune cells become able to enter the biofilm layer and selectively remove bacteria and fungi that they do not want to be present. The result is that the immune system is able to remove an infection in a wound or on the skin. MPPT, therefore, functions as passive immunotherapy. It has no antibacterial effects, but it can remove antibiotic-resistant infections and it will not contribute to the creation of new antimicrobial resistance.
Effects of MPPT on wound healing
MPPT has been evaluated in a preclincial wound healing model and in a 266 patient comparative clinical study, which included a wide range of wound types. The study found that MPPT reduced the time to achieving an infection-free and healing wound by 60% compared to a topical antibiotic (genamicin) and to the antiseptic iodine. MPPT also reduced the number of hospitalisation days by 31% compared to the antibiotic.
At Bristol University Hospital, MPPT |
https://en.wikipedia.org/wiki/SystemRescue | SystemRescue (Previously known as "SystemRescueCD") is a Linux distribution for x86 64 and x86 computers. The primary purpose of SystemRescue is to repair unbootable or otherwise damaged computer systems after a system crash. SystemRescue is not intended to be used as a permanent operating system. It runs from a Live CD, a USB flash drive or any type of hard drive. It was designed by a team led by François Dupoux, and is based on Arch Linux since version 6.0. Starting with version 6.0, it has systemd as its init system.
Features
SystemRescue is capable of graphics using the Linux framebuffer option for tools such as GParted. It has options such as connecting to the Internet through an ADSL modem or Ethernet and graphical web browsers such as Mozilla Firefox.
SystemRescue features include:
GNU Parted and GParted to partition disks and resize partitions, including FAT32 and NTFS
fdisk to edit the disk partition table
PartImage - disk imaging software which copies only used sectors
TestDisk - to recover lost partition and PhotoRec to recover lost data
smartmontools - a S.M.A.R.T. suite for HDD health reporting and data loss prevention
ddrescue - to extract recoverable data from physically damaged HDD and listing damaged sectors
FSArchiver - a system tool that allows you to save the contents of a file-system to a compressed archive file
nwipe - a secure data erasure tool (fork of DBAN) for harddrives to remove data remanence, supports Gutmann method plus other overwriting standard algorithms and patterns.
A CD and DVD burner - dvd+rw-tools
Two bootloaders - GRUB and SYSLINUX
Web browsers - Firefox, ELinks
File manager - emelFM2
Archiving and unarchiving abilities
File system tools - file system create, delete, resize, move
Support for many file systems, including full NTFS read/write access (via NTFS-3G) as well as FAT32 and Mac OS HFS
Support for Intel x86 and PowerPC systems, including Macs
Ability to create a boot disk for operating systems
Suppor |
https://en.wikipedia.org/wiki/Extrinsic%20mortality | Extrinsic mortality is the sum of the effects of external factors, such as predation, starvation and other environmental factors not under control of the individual that cause death. This is opposed to intrinsic mortality, which is the sum of the effects of internal factors contributing to normal, chronologic aging, such as, for example, mutations due to DNA replication errors, and which determined species maximum lifespan. Extrinsic mortality plays a significant role in evolutionary theories of aging, as well as the discussion of health barriers across socioeconomic borders.
Evolutionary theories of aging
Extrinsic mortality is implicit in both classical theories of aging and non-classical studies of aging. In both cases, its existence causes a selective pressure for either longer lifespans and later reproductive periods or shorter lifespans and earlier reproductive periods.
Classical theories of aging include:
Mutation Accumulation Theory of Aging - Because extrinsic mortality is so high in the natural world, few animals survive to old age. As a result, random harmful germ line mutations accumulate with little to no selective disadvantage.
Antagonistic Pleiotropy Hypothesis - Because pleiotropic genes that express phenotypes that increase fitness in early life and other phenotypes that decrease fitness in later life are generally selected for, harmful phenotypes contribute to senescence and an evolutionary tradeoff between lifespan and reproduction develops.
Disposable Soma Theory of Aging - Because resources are often limited and the influence of natural selection declines with age for similar reasons as the Mutation Accumulation theory of aging, organisms that invest greater amounts of energy into earlier reproduction rather than long term body maintenance are more successful. The lack of somatic maintenance and anti-aging mechanisms leads to senescence.
These classical evolutionary theories of aging postulate that quantities of extrinsic mortality factor |
https://en.wikipedia.org/wiki/Progress%20in%20Optics | Progress in Optics are a series of books edited by Emil Wolf published by Elsevier. They consist of collections of already published review articles deemed to be representative of the advances made in the fields of optics.
The series was established in 1962.
External links
Publications established in 1962
Physics books
Series of books
Elsevier books |
https://en.wikipedia.org/wiki/Libration%20%28molecule%29 | Libration (from the Latin verb librare "to balance, to sway"; cf. libra "scales") is a type of reciprocating motion in which an object with a nearly fixed orientation repeatedly rotates slightly back and forth. In physics and chemistry, a molecule (or other group of atoms) can undergo libration if it is subject to external forces or constraints that restrict its orientation.
For example, in liquid water, any given water molecule is attracted to neighboring molecules, so that it has a preferred orientation and cannot freely rotate. (Of course, over time, the neighboring molecules move around and the preferred orientation changes.) However, it can undergo librational motions, which are measureable in an infrared absorption spectrum and contribute to motional narrowing of other peaks, for instance the OH stretch.
Another example is a molecular crystal: Each molecular unit has a preferred orientation due to interactions with the nearby molecules, but they have librational modes corresponding to small rotations about this preferred orientation. |
https://en.wikipedia.org/wiki/Virtual%20PC | Virtual PC is an x86 emulator for PowerPC Mac hosts and a virtualization app for Microsoft Windows hosts. It was created by Connectix in 1997 and acquired by Microsoft in 2003. The Mac version was discontinued in 2006 following the Mac transition to Intel, while the Windows version was discontinued in 2011 in favour of Hyper-V.
Until version 4, Virtual PC only supported Classic Mac OS hosts. Version 4 was released in 2000 for both Mac OS and Windows, and version 5 (2001) added support for Mac OS X hosts. After Microsoft acquired Virtual PC from Connectix in 2003, the program was renamed Microsoft Virtual PC. In July 2006, Microsoft released the Windows version free of charge. In August 2006, Microsoft announced the Mac version would not be ported to Intel-based Macs, effectively discontinuing the product as PowerPC-based Macs would no longer be manufactured.
In 2009, Microsoft released Windows Virtual PC, which is only compatible with Windows 7 hosts, and is the technical foundation for the latter's Windows XP Mode. Windows Virtual PC does not officially support MS-DOS or operating systems older than Windows XP Professional SP3 as guests.
History
Connectix Virtual PC, Microsoft Virtual PC 2004, Microsoft Virtual PC 2007, and Windows Virtual PC are successive versions of the same software. Windows Virtual PC only runs on Windows 7. The earlier Microsoft versions which run on older versions of Windows were still available and support operating systems older than Windows XP. Starting in Windows 8, Microsoft replaced Virtual PC with Hyper-V.
Virtual PC by Connectix
Virtual PC was originally developed as a Macintosh application for System 7.5 and released by Connectix in June 1997. The first version of Virtual PC designed for Windows-based systems, version 4.0, was released in June 2001. Connectix sold versions of Virtual PC bundled with a variety of guest operating systems, including Windows, OS/2, and Red Hat Linux. As virtualization's importance to enterprise u |
https://en.wikipedia.org/wiki/Wrinklon | A wrinklon is a type of quasiparticle introduced in the study of wrinkling behavior in thin sheet materials, such as graphene or fabric. It is a localized excitation corresponding to wrinkles in a constrained two dimensional system.
It represents a localized region where two wrinkles in the material merge into one, serving as part of the pattern seen when the material forms wrinkles. The term "wrinklon" is derived from "wrinkle" and the suffix "-on", the latter commonly used in physics to denote quasiparticles, such as the "phonon" or "polaron".
The concept of wrinklons aids in understanding and describing the complex wrinkling patterns observed in a variety of materials. This understanding could prove useful in fields such as material science and nanotechnology, particularly in the study and development of two-dimensional materials like graphene.
Further studies have expanded the understanding of wrinklons, demonstrating that the behavior of these wrinkles in thin films, such as graphene, can differ depending on the substrate they are on. For instance, when graphene is on a compliant polymer substrate, the properties of the wrinklons change with the thickness of the graphene.
This suggests that the characteristics of the substrate have a significant role in wrinklon formation and behavior, which is important to consider in various applications of thin film materials.
See Also
Straintronics |
https://en.wikipedia.org/wiki/Molar%20mass | In chemistry, the molar mass () of a chemical compound is defined as the ratio between the mass and the amount of substance (measured in moles) of any sample of said compound. The molar mass is a bulk, not molecular, property of a substance. The molar mass is an average of many instances of the compound, which often vary in mass due to the presence of isotopes. Most commonly, the molar mass is computed from the standard atomic weights and is thus a terrestrial average and a function of the relative abundance of the isotopes of the constituent atoms on Earth. The molar mass is appropriate for converting between the mass of a substance and the amount of a substance for bulk quantities.
The molecular mass and formula mass are commonly used as a synonym of molar mass, particularly for molecular compounds; however, the most authoritative sources define it differently. The difference is that molecular mass is the mass of one specific particle or molecule, while the molar mass is an average over many particles or molecules.
The formula weight is a synonym of molar mass that is frequently used for non-molecular compounds, such as ionic salts.
The molar mass is an intensive property of the substance, that does not depend on the size of the sample. In the International System of Units (SI), the coherent unit of molar mass is kg/mol. However, for historical reasons, molar masses are almost always expressed in g/mol.
The mole was defined in such a way that the molar mass of a compound, in g/mol, is numerically equal to the average mass of one molecule, in daltons. It was exactly equal before the redefinition of the mole in 2019, and is now only approximately equal, but the difference is negligible for all practical purposes. Thus, for example, the average mass of a molecule of water is about 18.0153 daltons, and the molar mass of water is about 18.0153 g/mol.
For chemical elements without isolated molecules, such as carbon and metals, the molar mass is computed dividi |
https://en.wikipedia.org/wiki/Mathematical%20Tables%20Project | The Mathematical Tables Project was one of the largest and most sophisticated computing organizations that operated prior to the invention of the digital electronic computer. Begun in the United States in 1938 as a project of the Works Progress Administration (WPA), it employed 450 unemployed clerks to tabulate higher mathematical functions, such as exponential functions, logarithms, and trigonometric functions. These tables were eventually published in a 28-volume set by Columbia University Press.
History
The group was led by a group of mathematicians and physicists, most of whom had been unable to find professional work during the Great Depression. The mathematical leader was Gertrude Blanch, who had just finished her doctorate in mathematics at Cornell University. She had been unable to find a university position and was working at a photographic company before joining the project.
The administrative director was Arnold Lowan, who had a degree in physics from Columbia University and had spent a year at the Institute for Advanced Study in Princeton University before returning to New York without a job. Perhaps the most accomplished mathematician to be associated with the group was Cornelius Lanczos, who had once served as an assistant to Albert Einstein. He spent a year with the project and organized seminars on computation and applied mathematics at the project's office in Lower Manhattan.
In addition to computing tables of mathematical functions, the project did large computations for sciences, including the physicist Hans Bethe, and did calculations for a variety of war projects, including tables for the LORAN navigation system, tables for microwave radar, bombing tables, and shock wave propagation tables.
The Mathematical Tables Project survived the termination of the WPA in 1943 and continued to operate in New York until 1948. At that point, roughly 25 members of the group moved to Washington, D.C., to become the Computation Laboratory of the National Bur |
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