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https://en.wikipedia.org/wiki/Gorenstein
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Gorenstein may refer to:
Daniel Gorenstein (1923–1992), American mathematician, known for
Alperin–Brauer–Gorenstein theorem
Gorenstein–Harada theorem
Gorenstein ring
Gorenstein scheme
Gorenstein–Walter theorem
Eli Gorenstein (born 1952), Israeli actor, voice actor, singer and cellist
Friedrich Gorenstein (1932–2002), Ukrainian author and screenwriter
Hilda Goldblatt Gorenstein (Hilgos) (1905–1998), artist and inspiration for the documentary I Remember Better When I Paint
Mark Gorenstein (born 1946), Russian conductor
Horenstein may refer to:
Irving Howe (born Horenstein; 1920–1993). Jewish American literary and social critic
Jascha Horenstein (1898–1973), Ukrainian-born American conductor
See also
Hornstein (surname)
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https://en.wikipedia.org/wiki/CCISD
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CCISD may refer to:
Copperas Cove Independent School District
Corpus Christi Independent School District
Clear Creek Independent School District
Corrigan-Camden Independent School District
Crystal City Independent School District
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https://en.wikipedia.org/wiki/SISD
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SISD can refer to:
Single instruction, single data, a computer processor architecture
CCL5, an 8kDa protein also using the symbol SISD
Sixteen-segment display
Several school districts in Texas. See List of school districts in Texas - S
Saginaw Intermediate School District (Michigan)
Southeast Island School District (Alaska)
Swiss International Scientific School in Dubai
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https://en.wikipedia.org/wiki/4-meter%20band
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The 4-metre (70 MHz) band is an amateur radio band within the lower part of the very high frequency (VHF) band.
As only a few countries within and outside of Europe have allocated the band for amateur radio access, the availability of dedicated commercially manufactured equipment is limited. Most radio amateurs active on the band are interested in home construction or the modification of private mobile radio (PMR) equipment. As a result, communication on the 4-metre band tends to focus on technical topics, with long 'rag chews' being the norm as long as there is some local activity.
History
Before World War II, British community radio stations had been allocated a band at 56 MHz. After the war ended, they were moved to the 5 metre band (58.5–60 MHz) instead. This only lasted until 1949, as the 5 metre band was earmarked for BBC Television broadcasts. Meanwhile, in 1948, 72–72.8 MHz was allocated to France (until 1961).
In 1956, after several years of intense lobbying by the Radio Society of Great Britain (RSGB), the 4 metre band was allocated to British community radio stations as a replacement for the old 5 metre band allocation. For several years the 4 metre band allocation was only 200 kHz wide, from 70.2–70.4 MHz; it was later extended to 70.025–70.7 MHz. The band limits were subsequently moved to today's 500 kHz allocation of 70.0–70.5 MHz.
On the occasion of the International Geophysical Year 1957–1958, the following countries have been allocated frequencies betwe
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https://en.wikipedia.org/wiki/Versor
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In mathematics, a versor is a quaternion of norm one (a unit quaternion). Each versor has the form
where the r2 = −1 condition means that r is a unit-length vector quaternion (or that the first component of r is zero, and the last three components of r are a unit vector in 3 dimensions). The corresponding 3-dimensional rotation has the angle 2a about the axis r in axis–angle representation. In case (a right angle), then , and the resulting unit vector is termed a right versor.
The collection of versors with quaternion multiplication forms a group, and the set of versors is a 3-sphere in the 4-dimensional quaternion algebra.
Presentation on 3- and 2-spheres
Hamilton denoted the versor of a quaternion q by the symbol Uq. He was then able to display the general quaternion in polar coordinate form
q = Tq Uq,
where Tq is the norm of q. The norm of a versor is always equal to one; hence they occupy the unit 3-sphere in H. Examples of versors include the eight elements of the quaternion group. Of particular importance are the right versors, which have angle π/2. These versors have zero scalar part, and so are vectors of length one (unit vectors). The right versors form a sphere of square roots of −1 in the quaternion algebra. The generators i, j, and k are examples of right versors, as well as their additive inverses. Other versors include the twenty-four Hurwitz quaternions that have the norm 1 and form vertices of a 24-cell polychoron.
Hamilton defined a quaternion as the q
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https://en.wikipedia.org/wiki/Lactase%20persistence
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Lactase persistence is the continued activity of the lactase enzyme in adulthood, allowing the digestion of lactose in milk. In most mammals, the activity of the enzyme is dramatically reduced after weaning. In some human populations though, lactase persistence has recently evolved as an adaptation to the consumption of nonhuman milk and dairy products beyond infancy. Lactase persistence is very high among northern Europeans, especially Irish people. Worldwide, most people are lactase non-persistent, and are affected by varying degrees of lactose intolerance as adults. However, lactase persistence and lactose intolerance do not always overlap.
Global distribution of the phenotype
The distribution of the lactase persistence (LP) phenotype, or the ability to digest lactose into adulthood, is not homogeneous in the world. Lactase persistence frequencies are highly variable. In Europe, the distribution of the lactase persistence phenotype is clinal, with frequencies ranging from 15–54% in the south-east to 89–96% in the north-west. For example, only 17% of Greeks and 14% of Sardinians are predicted to possess this phenotype, while around 80% of Finns and Hungarians and 100% of Irish people are predicted to be lactase persistent. Similarly, the frequency of lactase-persistence is clinal in India, a 2011 study of 2,284 individuals identifying a prevalence of LP in the Ror community, of Haryana, in the North West, of 48.95%, declining to 1.5% in the Andamanese, of the South East,
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https://en.wikipedia.org/wiki/Timoga%20Spring
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Timoga Springs is a collection of springs located at Timoga-Buru-un, in Iligan City, Philippines. It is well known for icy-cool, crystal-clear springs that flow freely to swimming pools of different sizes. There are approximately five spring resorts along the highway, which is easily accessible by land to all locals and tourists.
The source of water of Timoga Springs comes from Lake Lanao in Marawi City, Lanao del Sur—which is 37 kilometers away. Lake Lanao waters come from a volcanic source, the lake being the crater of an extinct volcano. These waters are filtered underground in the Timoga, Buru-un area of Iligan, making it one of the richest source of fresh, high-pH, alkaline mineral water.
Lake Lanao is categorized as the largest fresh water lake in the Philippines, since findings show that Laguna Lake has salt water intrusion.
An ongoing project using its pristine waters for bulk water exportation and mineral water distribution is now being undertaken by Arnold A. Garbanzos, a member of the Rotary Club of Iligan, in coordination with the Macapagal-Dela Cruz-Macaraeg families and the Marzo family. The project is called Lanao Halal Waters and is intended to make Iligan and Marawi the "hydro dollar capital" of the Philippines. Its main markets are the Middle East, India and China, where water is scarce. The intention is to create a Cooperative and a Foundation where the Tri-people of Iligan can participate.
Out of the Lanao Halal Waters projects, the Hajj Fund, will
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https://en.wikipedia.org/wiki/The%20Parrot%27s%20Theorem
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The Parrot's Theorem is a French novel written by Denis Guedj and published in 1998. An English translation was published in 2000.
Plot summary
The plot revolves around a household in Paris: Mr Ruche, an elderly wheelchair-using bookseller, his employee and housemate Perrette, and Perrette's three children – teenage twins and young Max, who is deaf. Max liberates a talking parrot at the market and Mr Ruche receives a consignment of mathematical books from an old friend, who has lived in Brazil for decades without any contact between the two.
The household sets up its own exploration of mathematics in order to crack the code of the last messages from Mr Ruche's old friend, now apparently murdered. Mathematical topics covered in the book include primes and factors; irrational and amicable numbers; the discoveries of Pythagoras, Archimedes and Euclid; and the problems of squaring the circle and doubling the cube.
The mathematics is real mathematics, woven into an historical sequence as a series of intriguing problems, bringing their own stories with them.
See also
Forrest Library
Numbers: The Universal Language
References
Imaginary numbers, A review of The Parrot's Theorem by Simon Singh.
1998 French novels
Books about parrots
Novels about mathematics
Novels set in Paris
Weidenfeld & Nicolson books
Novels about birds
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https://en.wikipedia.org/wiki/Synthetic%20alexandrite
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Synthetic alexandrite is an artificially grown crystalline variety of chrysoberyl, composed of beryllium aluminum oxide (BeAlO).
The name is also often used erroneously to describe synthetically-grown corundum that simulates the appearance of alexandrite, but with a different mineral composition.
Manufacture
Most true synthetic alexandrite is grown by the Czochralski method, known as “pulling”. Another method is a “floating zone”, developed in 1964 by an Armenian scientist Khachatur Saakovich Bagdasarov, of the Russian (former Soviet) Institute of Crystallography, Moscow. Bagdasarov’s floating zone method was widely used to manufacture white YAG for spacecraft and submarine lighting, before the process found its way into jewelry production. Alexandrite crystals grown by floating zone method tend to have less intensity in color than crystals grown by the pulled method.
Flux-grown alexandrite stones are expensive to make and are grown in platinum crucibles. Crystals of platinum may still be evident in the cut stones. Alexandrite grown by the flux-melt process will contain particles of flux, resembling liquid “feathers” with a refractive index and specific gravity that echo that of natural alexandrite. Some stones contain parallel groups of negative crystals. Due to the high cost of this process, it is no longer used commercially.
The largest producer of jewelry quality laboratory-grown alexandrite to this day is Tairus. Production capacity is in the range of 100 kg/year.
C
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https://en.wikipedia.org/wiki/Illam
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Illam (), also referred to as Mana, is the Malayalam word for the house of a Namboodiri Brahmin. In the traditional lineage system used for the classification and identification of homes based on the castes of Kerala, South India, an Illam served as the Tharavad (ancestral house) of Namboodiri Brahmin families.
The Namboodiris, who constituted the highest ranking caste of Kerala, also refer to their lineages as the Brahmaalayam. The family homes are built according to the canons of Vaasthusaasthram, meaning "architecture" in the Sanskrit language.
Structural layout
The traditional layout of a Namboodiri Illam is in the form of an open courtyard which is located in the middle, known as the Nadumittam ('nadu' meaning middle and 'mittam' meaning earth/ground). These buildings or houses are designed in different patterns such as Nalukettu (a courtyard surrounded by rooms on four sides), Ettukettu (a nalukettu surrounded by another nalukettu), and Pathinarukettu (four layers of buildings constructed around a central courtyard).
Popular examples
Some well-known Illams in Kerala include Suryakaladi Mana (Kottayam), Varikkasseri Mana (Palakkad), Pootheri Illam (Feroke), Eettisseri Mana (Kannur), Nenmini Illam (Guruvayur), Olappamanna Illam (Vellinezhi) and Poomulli Mana (Palakkad). Most of these ancestral homes produced aristocratic families who have since married with other Nambudiri families and in some cases, elite Nair communities to form the upper-caste divisions.
Refer
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https://en.wikipedia.org/wiki/Portal%20rendering
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In computer-generated imagery and real-time 3D computer graphics, portal rendering is an algorithm for visibility determination. For example, consider a 3D computer game environment, which may contain many polygons, only a few of which may be visible on screen at a given time. By determining which polygons are currently not visible, and not rendering those objects, significant performance improvements can be achieved.
A portal system is based on using the partitioning of space to form generalizations about the visibility of objects within those spaces. Regions of map space are divided into polygonal, generally convex, areas called zones, or sometimes sectors. Adjacent zones are linked to one another via shared dividing polygons termed portals. Approaches that precompute visibility for zones are referred to as potentially visible set or PVS methods.
For example, in a computer game such as Descent, the game area might be divided into several zones. These zones would then be connected to each other by small openings such as doors or windows. These openings are referred to as portals. When the zone behind a portal needs to be drawn, the only parts that are visible are the parts that can be seen through the portal. Therefore, the zone can be clipped against the portal boundaries to remove overdraw.
The use of portals simplifies the game engine's task of determining visible areas and objects from any given point of view of the level, and simplifies rendering by allowing it to us
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https://en.wikipedia.org/wiki/Death%20effector%20domain
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The death-effector domain (DED) is a protein interaction domain found only in eukaryotes that regulates a variety of cellular signalling pathways. The DED domain is found in inactive procaspases (cysteine proteases) and proteins that regulate caspase activation in the apoptosis cascade such as FAS-associating death domain-containing protein (FADD). FADD recruits procaspase 8 and procaspase 10 into a death induced signaling complex (DISC). This recruitment is mediated by a homotypic interaction between the procaspase DED and a second DED that is death effector domain in an adaptor protein that is directly associated with activated TNF receptors. Complex formation allows proteolytic activation of procaspase into the active caspase form which results in the initiation of apoptosis (cell death). Structurally the DED domain are a subclass of protein motif known as the death fold and contains 6 alpha helices, that closely resemble the structure of the Death domain (DD).
Structure
DED is a subfamily of the DD superfamily (other recognizable domains in this superfamily are: caspase-recruitment domain (CARD), pyrin domain (PYD) and death domain (DD)). The subfamilies resemble structurally one another, all of them (and DED in particular) are composed of a bundle of 6 alpha-helices, but they diverge in the surface features.
The complete primary structure of this proteic domain has not been consensually defined. Some studies described residues 2-184, but C-terminus and N-terminus r
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https://en.wikipedia.org/wiki/Metabolic%20network
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A metabolic network is the complete set of metabolic and physical processes that determine the physiological and biochemical properties of a cell. As such, these networks comprise the chemical reactions of metabolism, the metabolic pathways, as well as the regulatory interactions that guide these reactions.
With the sequencing of complete genomes, it is now possible to reconstruct the network of biochemical reactions in many organisms, from bacteria to human. Several of these networks are available online:
Kyoto Encyclopedia of Genes and Genomes (KEGG), EcoCyc, BioCyc and metaTIGER.
Metabolic networks are powerful tools for studying and modelling metabolism.
Uses
Metabolic networks can be used to detect comorbidity patterns in diseased patients. Certain diseases, such as obesity and diabetes, can be present in the same individual concurrently, sometimes one disease being a significant risk factor for the other disease. The disease phenotypes themselves are normally the consequence of the cell's inability to breakdown or produce an essential substrate. However, an enzyme defect at one reaction may affect the fluxes of other subsequent reactions. These cascading effects couple the metabolic diseases associated with subsequent reactions resulting in comorbidity effects. Thus, metabolic disease networks can be used to determine if two disorders are connected due to their correlated reactions.
See also
Metabolic network modelling
Metabolic pathway
References
Metabolism
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https://en.wikipedia.org/wiki/Superposition%20calculus
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The superposition calculus is a calculus for reasoning in equational logic. It was developed in the early 1990s and combines concepts from first-order resolution with ordering-based equality handling as developed in the context of (unfailing) Knuth–Bendix completion. It can be seen as a generalization of either resolution (to equational logic) or unfailing completion (to full clausal logic). Like most first-order calculi, superposition tries to show the unsatisfiability of a set of first-order clauses, i.e. it performs proofs by refutation. Superposition is refutation complete—given unlimited resources and a fair derivation strategy, from any unsatisfiable clause set a contradiction will eventually be derived.
, most of the (state-of-the-art) theorem provers for first-order logic are based on superposition (e.g. the E equational theorem prover), although only a few implement the pure calculus.
Implementations
E
SPASS
Vampire
Waldmeister (official web page)
References
Rewrite-Based Equational Theorem Proving with Selection and Simplification, Leo Bachmair and Harald Ganzinger, Journal of Logic and Computation 3(4), 1994.
Paramodulation-Based Theorem Proving, Robert Nieuwenhuis and Alberto Rubio, Handbook of Automated Reasoning I(7), Elsevier Science and MIT Press, 2001.
Mathematical logic
Logical calculi
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https://en.wikipedia.org/wiki/Ellenborough%20Park%2C%20Weston-super-Mare
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Ellenborough Park is a suburb consisting of a park situated in the centre of Weston-super-Mare, North Somerset, England.
The western half of the park, an area of , is of significant biodiversity interest, due to its plant communities, and was notified as a biological Site of Special Scientific Interest in 1989. The eastern half of the park contains a play area for local children, which was opened in 2005.
Ellenborough Park was also the subject of a significant legal case Re Ellenborough Park in 1955 which determined criteria for easements in English property law.
Site description
The park is situated inland from Weston-super-Mare beach, on a site which was formerly part of a sand dune system of the Bristol Channel. The soil here is calcareous and sandy, and the short-turf grassland which is supports is believed to be remnant dune grassland from this dune system, which was enclosed in the 19th century.
Vegetation
The species composition of this grassland includes the following grasses:
Sand Cat's-tail (Phleum arenarium), Red Fescue (Festuca rubra), Sea Fern-grass (Desmazeria marina) and Cock's-foot (Dactylis glomerata). Herb species present include Sea Stork's-bill (Erodium maritimum), Buck's-horn Plantain (Plantago coronopus), Rough Clover (Trifolium scabrum), all of which are indicative of a maritime influence, plus Wild Clary (Salvia verbenaca), Smooth Hawk's-beard (Crepis capillaris) and Pink-sorrel (Oxalis articulata).
Ellenborough Park supports two Red Data Book
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https://en.wikipedia.org/wiki/Quantum-cascade%20laser
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Quantum-cascade lasers (QCLs) are semiconductor lasers that emit in the mid- to far-infrared portion of the electromagnetic spectrum and were first demonstrated by Jérôme Faist, Federico Capasso, Deborah Sivco, Carlo Sirtori, Albert Hutchinson, and Alfred Cho at Bell Laboratories in 1994.
Unlike typical interband semiconductor lasers that emit electromagnetic radiation through the recombination of electron–hole pairs across the material band gap, QCLs are unipolar, and laser emission is achieved through the use of intersubband transitions in a repeated stack of semiconductor multiple quantum well heterostructures, an idea first proposed in the article "Possibility of amplification of electromagnetic waves in a semiconductor with a superlattice" by R. F. Kazarinov and R. A. Suris in 1971.
Intersubband vs. interband transitions
Within a bulk semiconductor crystal, electrons may occupy states in one of two continuous energy bands — the valence band, which is heavily populated with low energy electrons and the conduction band, which is sparsely populated with high energy electrons. The two energy bands are separated by an energy band gap in which there are no permitted states available for electrons to occupy. Conventional semiconductor laser diodes generate light by a single photon being emitted when a high energy electron in the conduction band recombines with a hole in the valence band. The energy of the photon and hence the emission wavelength of laser diodes is therefore
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https://en.wikipedia.org/wiki/Fresnel%20diffraction
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In optics, the Fresnel diffraction equation for near-field diffraction is an approximation of the Kirchhoff–Fresnel diffraction that can be applied to the propagation of waves in the near field. It is used to calculate the diffraction pattern created by waves passing through an aperture or around an object, when viewed from relatively close to the object. In contrast the diffraction pattern in the far field region is given by the Fraunhofer diffraction equation.
The near field can be specified by the Fresnel number, , of the optical arrangement. When the diffracted wave is considered to be in the Fraunhofer field. However, the validity of the Fresnel diffraction integral is deduced by the approximations derived below. Specifically, the phase terms of third order and higher must be negligible, a condition that may be written as
where is the maximal angle described by and the same as in the definition of the Fresnel number.
The multiple Fresnel diffraction at closely spaced periodical ridges (ridged mirror) causes the specular reflection; this effect can be used for atomic mirrors.
Early treatments of this phenomenon
Some of the earliest work on what would become known as Fresnel diffraction was carried out by Francesco Maria Grimaldi in Italy in the 17th century. In his monograph entitled "Light", Richard C. MacLaurin explains Fresnel diffraction by asking what happens when light propagates, and how that process is affected when a barrier with a slit or hole in it i
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https://en.wikipedia.org/wiki/Latent%20and%20observable%20variables
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In statistics, latent variables (from Latin: present participle of lateo, “lie hidden”) are variables that can only be inferred indirectly through a mathematical model from other observable variables that can be directly observed or measured. Such latent variable models are used in many disciplines, including political science, demography, engineering, medicine, ecology, physics, machine learning/artificial intelligence, bioinformatics, chemometrics, natural language processing, management, psychology and the social sciences.
Latent variables may correspond to aspects of physical reality. These could in principle be measured, but may not be for practical reasons. In this situation, the term hidden variables is commonly used (reflecting the fact that the variables are meaningful, but not observable). Other latent variables correspond to abstract concepts, like categories, behavioral or mental states, or data structures. The terms hypothetical variables or hypothetical constructs may be used in these situations.
The use of latent variables can serve to reduce the dimensionality of data. Many observable variables can be aggregated in a model to represent an underlying concept, making it easier to understand the data. In this sense, they serve a function similar to that of scientific theories. At the same time, latent variables link observable "sub-symbolic" data in the real world to symbolic data in the modeled world.
Examples
Psychology
Latent variables, as created by fac
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https://en.wikipedia.org/wiki/2%2C4-Dinitrotoluene
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2,4-Dinitrotoluene (DNT) or dinitro is an organic compound with the formula C7H6N2O4. This pale yellow crystalline solid is well known as a precursor to trinitrotoluene (TNT) but is mainly produced as a precursor to toluene diisocyanate.
Isomers of dinitrotoluene
Six positional isomers are possible for dinitrotoluene. The most common one is 2,4-dinitrotoluene. The nitration of toluene gives sequentially mononitrotoluene, DNT, and finally TNT. 2,4-DNT is the principal product from dinitration, the other main product being about 30% 1,3-DN2-T. The nitration of 4-nitrotoluene gives 2,4-DNT.
Applications
Most DNT is used in the production of toluene diisocyanate, which is used to produce flexible polyurethane foams. DNT is hydrogenated to produce 2,4-toluenediamine, which in turn is phosgenated to give toluene diisocyanate. In this way, about 1.4 billion kilograms are produced annually, as of the years 1999–2000. Other uses include the explosives industry. It is not used by itself as an explosive, but some of the production is converted to TNT.
Dinitrotoluene is frequently used as a plasticizer, deterrent coating, and burn rate modifier in propellants (e.g., smokeless gunpowders). As it is carcinogenic and toxic, modern formulations tend to avoid its use. In this application it is often used together with dibutyl phthalate.
Toxicity
Dinitrotoluenes are highly toxic with a threshold limit value (TLV) of 1.5 mg/m3. It converts hemoglobin into methemoglobin.
2,4-Dinitrotoluene
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https://en.wikipedia.org/wiki/Saline%20seep
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A saline seep is seep of saline water, with an area of alkali salt crystals that form when the salty water reaches the surface and evaporates. Various types of water movement form saline seeps, including capillary action from a water table under the surface, and a water table being brought to the surface in a flow.
Habitat
Biota adapted to saline conditions, often endemic, thrive in the specialized habitat.
Agriculture
Saline seeps are considered detrimental for agriculture, as they may reduce yields and restrict growth.
See also
Salinity
Soil salinity
Soil salination
Brackish water
Spring (hydrosphere)
References
Springs (hydrology)
Salt flats
Hydrogeology
Soil
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https://en.wikipedia.org/wiki/Viy
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Viy or VIY may refer to:
Вий or "Viy" (story), Russian horror novella by Nikolai Gogol published 1835
Numerous derivative works, among those listed at Viy (story)#Film adaptations being:
Viy (1909 film), a 1909 Russian lost film
Viy (1967 film), based on the Nikolai Gogol story
Viy (2014 film), a dark fantasy film inspired by Gogol story
Viy 2: Journey to China, a sequel to the 2014 film
Viy (band), a Ukrainian band
Viy, Azerbaijan, a village in Lankaran Rayon
Vélizy-Villacoublay Air Base (IATA: VIY), Villacoublay, France
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https://en.wikipedia.org/wiki/AVR%20Butterfly
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The AVR Butterfly is a battery-powered single-board microcontroller developed by Atmel. It consists of an Atmel ATmega169PV Microcontroller, a liquid crystal display, joystick, speaker, serial port, real-time clock (RTC), internal flash memory, and sensors for temperature and voltage. The board is the size of a name tag and has a clothing pin on back so it can be worn as such after the user enters their name onto the LCD.
Feature set
LCD
The AVRButterfly demonstrates LCD driving by running a 14 segment, six alpha-numeric character display. However, the LCD interface consumes many of the I/O pins.
CPU & Speed
The Butterfly's ATmega169 CPU is capable of speeds up to 8 MHz, however it is factory set by software to 2 MHz to preserve the button battery life. There are free replacement bootloaders available that will launch programs at 1, 2, 4 or 8 MHz speeds. Alternatively, this may be accomplished by changing the CPU prescaler in the application code.
Features
ATmega169V AVR 8-bit CPU, including 16 Kbyte of Flash memory for code storage and 512 bytes of EEPROM for data storage
100-segment LCD (without backlight)
4-Mbit (512-Kbyte) AT45 flash memory
4-way Mini-Joystick with center push-button
Light, temperature, and voltage (0-5 V range) sensors (light sensor no longer included due to the RoHS directive)
Piezo speaker
Solder pads for user-supplied connectors: 2 8-bit I/O ports, ISP, USI, JTAG
RS232 level converter & interface (Cable and connector provided by end
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https://en.wikipedia.org/wiki/UTM%20theorem
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In computability theory, the theorem, or universal Turing machine theorem, is a basic result about Gödel numberings of the set of computable functions. It affirms the existence of a computable universal function, which is capable of calculating any other computable function. The universal function is an abstract version of the universal Turing machine, thus the name of the theorem.
Roger's equivalence theorem provides a characterization of the Gödel numbering of the computable functions in terms of the smn theorem and the UTM theorem.
Theorem
The theorem states that a partial computable function u of two variables exists such that, for every computable function f of one variable, an e exists such that for all x. This means that, for each x, either f(x) and u(e,x) are both defined and are equal, or are both undefined.
The theorem thus shows that, defining φe(x) as u(e, x), the sequence φ1, φ2, … is an enumeration of the partial computable functions. The function in the statement of the theorem is called a universal function.
References
Theorems in theory of computation
Computability theory
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https://en.wikipedia.org/wiki/Affinity%20label
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Affinity labels are a class of enzyme inhibitors that covalently bind to their target causing its inactivation. The hallmark of an affinity label is the use of a targeting moiety to specifically and reversibly deliver a weakly reactive group to the enzyme that irreversibly binds to an amino acid residue. The targeting portion of the label often resembles the enzyme's natural substrate so that a similar mode of noncovalent binding is used prior to the covalent linkage. Their usefulness in medicine can be limited by the specificity of the first noncovalent binding step whereas indiscriminate action can be utilized for purposes such as affinity labeling - a technique for the validation of substrate-specific binding of compounds.
These labels are not limited to enzymes but may also be designed to react with antibodies or ribozymes although this usage is less common. Although proteins such as hemoglobin do not have an active site, binding pockets can be exploited for their affinity and thus be labeled.
Classifications
Affinity labels can be broken down into three distinct categories based on their reactive groups and mode of delivery.
Classical affinity labels
This category encompasses the simplest approach of coupling an electrophile with low intrinsic reactivity to a noncovalent binding moiety which frequently mimics the natural substrate. Key to this designation is that the reactivity of the electrophile is not altered by the enzyme and that the noncovalent binding moiet
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https://en.wikipedia.org/wiki/Suicide%20inhibition
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In biochemistry, suicide inhibition, also known as suicide inactivation or mechanism-based inhibition, is an irreversible form of enzyme inhibition that occurs when an enzyme binds a substrate analog and forms an irreversible complex with it through a covalent bond during the normal catalysis reaction. The inhibitor binds to the active site where it is modified by the enzyme to produce a reactive group that reacts irreversibly to form a stable inhibitor-enzyme complex. This usually uses a prosthetic group or a coenzyme, forming electrophilic alpha and beta unsaturated carbonyl compounds and imines.
Examples
Some clinical examples of suicide inhibitors include:
Disulfiram, which inhibits the acetaldehyde dehydrogenase enzyme.
Aspirin, which inhibits cyclooxygenase 1 and 2 enzymes.
Clavulanic acid, which inhibits β-lactamase: clavulanic acid covalently bonds to a serine residue in the active site of the β-lactamase, restructuring the clavulanic acid molecule, creating a much more reactive species that attacks another amino acid in the active site, permanently inactivating it, and thus inactivating the enzyme β-lactamase.
Penicillin, which inhibits DD-transpeptidase from building bacterial cell walls.
Sulbactam, which prohibits penicillin-resistant strains of bacteria from metabolizing penicillin.
AZT (zidovudine) and other chain-terminating nucleoside analogues used to inhibit HIV-1 reverse transcriptase in the treatment of HIV/AIDS.
Eflornithine, one of the drugs use
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https://en.wikipedia.org/wiki/Southwestern%20blot
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The southwestern blot, is a lab technique that involves identifying as well as characterizing DNA-binding proteins by their ability to bind to specific oligonucleotide probes. Determination of molecular weight of proteins binding to DNA is also made possible by the technique. The name originates from a combination of ideas underlying Southern blotting and Western blotting techniques of which they detect DNA and protein respectively. Similar to other types of blotting, proteins are separated by SDS-PAGE and are subsequently transferred to nitrocellulose membranes. Thereafter southwestern blotting begins to vary with regards to procedure as since the first blotting’s, many more have been proposed and discovered with goals of enhancing results. Former protocols were hampered by the need for large amounts of proteins and their susceptibility to degradation while being isolated.
Southwestern blotting was first described by Brian Bowen, Jay Steinberg, U.K. Laemmli, and Harold Weintraub in 1979. During the time the technique was originally called "protein blotting". While there were existing techniques for purification of proteins associated with DNA, they often had to be used together to yield desired results. Thus, Bowen and colleagues sought to describe a procedure that could simplify the current methods of their time.
Method
Original Method
To begin, proteins of interest are prepared for the SDS-PAGE technique and subsequently loaded onto the gel for separation on the basi
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https://en.wikipedia.org/wiki/AutoSketch
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AutoSketch is a 2D vector drawing program by Autodesk. It is less powerful than Autodesk's AutoCAD and does not support 3D models.
AutoSketch uses SKD and SKF, in later versions, as its native format, but can support DWG and DXF. Version 2.1 for Windows supported macros which has been removed in later versions.
History
AutoSketch was developed by Foresight Resources under the name "Drafix" to run under Microsoft DOS, and was one of the first Windows based CAD software products. An Atari ST version was also available around 1989. Drafix won the first American Institute of Architect's "CAD Shoot-out". Among the features that made the original Drafix stand out when compared to the much more expensive AutoCAD were the ease of learning, the variety of dimensioning available out of the box, including relative dimensions, and being able to draw new primitives (line, circle, square, etc.) relative to existing primitives or points on them using keyboard shortcuts. One limitation of the first DOS release was that it needed to store all of a drawing in RAM, while editing and could not use any sort of swapping. This limited the size of the drawings. In later versions Drafix took advantage of virtual memory available in Windows to edit more complex drawings. One important limitation was that while Drafix was a complete drawing tool at a reasonable price for many industries, especially architecture and industrial design with relatively small drawings, it lacked the extendability Au
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https://en.wikipedia.org/wiki/Raised%20cosine%20distribution
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In probability theory and statistics, the raised cosine distribution is a continuous probability distribution supported on the interval . The probability density function (PDF) is
for and zero otherwise. The cumulative distribution function (CDF) is
for and zero for and unity for .
The moments of the raised cosine distribution are somewhat complicated in the general case, but are considerably simplified for the standard raised cosine distribution. The standard raised cosine distribution is just the raised cosine distribution with and . Because the standard raised cosine distribution is an even function, the odd moments are zero. The even moments are given by:
where is a generalized hypergeometric function.
See also
Hann function
Havercosine (hvc)
References
Continuous distributions
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https://en.wikipedia.org/wiki/Heusler%20compound
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Heusler compounds are magnetic intermetallics with face-centered cubic crystal structure and a composition of XYZ (half-Heuslers) or X2YZ (full-Heuslers), where X and Y are transition metals and Z is in the p-block. The term derives from the name of German mining engineer and chemist Friedrich Heusler, who studied such a compound (Cu2MnAl) in 1903. Many of these compounds exhibit properties relevant to spintronics, such as magnetoresistance, variations of the Hall effect, ferro-, antiferro-, and ferrimagnetism, half- and semimetallicity, semiconductivity with spin filter ability, superconductivity, topological band structure and are actively studied as Thermoelectric materials. Their magnetism results from a double-exchange mechanism between neighboring magnetic ions. Manganese, which sits at the body centers of the cubic structure, was the magnetic ion in the first Heusler compound discovered. (See the Bethe–Slater curve for details of why this happens.)
Styles of writing chemical formula
Depending on the field of literature being surveyed, one might encounter the same compound referred to with different chemical formulas. An example of the most common difference is X2YZ versus XY2Z, where the reference to the two transition metals X and Y in the compound are swapped. The traditional convention X2YZ arises from the interpretation of Heuslers as intermetallics and used predominantly in literature studying magnetic applications of Heuslers compounds. The XY2Z convention on t
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https://en.wikipedia.org/wiki/Hertz%20%28disambiguation%29
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The hertz (symbol: Hz) is the SI derived unit of frequency.
Hertz may also refer to:
People
Hertz (name), a German surname that has also been used as a given name.
Heinrich Hertz, (1857–1894), German physicist after whom the unit of frequency was named
Places
16761 Hertz, a minor planet
Hertz (crater), on Moon
Arts and entertainment
"Hertz", a song by Amyl and the Sniffers from their 2021 album Comfort to Me
"Hertz", a song by Eden from his 2020 album No Future
Companies and organizations
The Hertz Corporation, American car and equipment rental service
Hertz Car Sales division
Hertz Foundation, a charitable foundation in Livermore, California
50Hertz Transmission GmbH, one of the 4 electric transmission operators in Germany
See also
Herz (disambiguation)
Hurts (disambiguation)
Franck–Hertz experiment, fundamental physics
Herts, an abbreviation of Hertfordshire
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https://en.wikipedia.org/wiki/Indole-3-butyric%20acid
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Indole-3-butyric acid (1H-indole-3-butanoic acid, IBA) is a white to light-yellow crystalline solid, with the molecular formula C12H13NO2. It melts at 125 °C in atmospheric pressure and decomposes before boiling. IBA is a plant hormone in the auxin family and is an ingredient in many commercial horticultural plant rooting products.
Plant hormone
Since IBA is not completely soluble in water, it is typically dissolved in 75% or purer alcohol for use in plant rooting, making a solution of between 10,000 and 50,000 ppm. This alcohol solution is then diluted with distilled water to the desired concentration. IBA is also available as a salt, which is soluble in water. The solution should be kept in a cool, dark place for best results.
This compound had been thought to be strictly synthetic; however, it was reported that the compound was isolated from leaves and seeds of maize and other species. In maize, IBA has been shown to be biosynthesized in vivo from IAA and other compounds as precursors. This chemical may also be extracted from any of the Salix (Willow) genus.
Plant tissue culture
In plant tissue culture IBA and other auxins are used to initiate root formation in vitro in a procedure called micropropagation. Micropropagation of plants is the process of using small samples of plants called explants and causing them to undergo growth of differentiated or undifferentiated cells. In connection with cytokinins like kinetin, auxins like IBA can be used to cause the formation
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https://en.wikipedia.org/wiki/Van%20Stockum%20dust
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In general relativity, the van Stockum dust is an exact solution of the Einstein field equations in which the gravitational field is generated by dust rotating about an axis of cylindrical symmetry. Since the density of the dust is increasing with distance from this axis, the solution is rather artificial, but as one of the simplest known solutions in general relativity, it stands as a pedagogically important example.
This solution is named after Willem Jacob van Stockum, who rediscovered it in 1937 independently of a much earlier discovery by Cornelius Lanczos in 1924. It is currently recommended that the solution be referred to as the Lanczos–van Stockum dust.
Derivation
One way of obtaining this solution is to look for a cylindrically symmetric perfect fluid solution in which the fluid exhibits rigid rotation. That is, we demand that the world lines of the fluid particles form a timelike congruence having nonzero vorticity but vanishing expansion and shear. (In fact, since dust particles feel no forces, this will turn out to be a timelike geodesic congruence, but we won't need to assume this in advance.)
A simple Ansatz corresponding to this demand is expressed by the following frame field, which contains two undetermined functions of :
To prevent misunderstanding, we should emphasize that taking the dual coframe
gives the metric tensor in terms of the same two undetermined functions:
Multiplying out gives
We compute the Einstein tensor with respect to this fra
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https://en.wikipedia.org/wiki/Kakutani%20fixed-point%20theorem
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In mathematical analysis, the Kakutani fixed-point theorem is a fixed-point theorem for set-valued functions. It provides sufficient conditions for a set-valued function defined on a convex, compact subset of a Euclidean space to have a fixed point, i.e. a point which is mapped to a set containing it. The Kakutani fixed point theorem is a generalization of the Brouwer fixed point theorem. The Brouwer fixed point theorem is a fundamental result in topology which proves the existence of fixed points for continuous functions defined on compact, convex subsets of Euclidean spaces. Kakutani's theorem extends this to set-valued functions.
The theorem was developed by Shizuo Kakutani in 1941, and was used by John Nash in his description of Nash equilibria. It has subsequently found widespread application in game theory and economics.
Statement
Kakutani's theorem states:
Let S be a non-empty, compact and convex subset of some Euclidean space Rn.
Let φ: S → 2S be a set-valued function on S with the following properties:
φ has a closed graph; φ(x) is non-empty and convex for all x ∈ S.Then φ has a fixed point.Definitions
Set-valued function A set-valued function φ from the set X to the set Y is some rule that associates one or more points in Y with each point in X. Formally it can be seen just as an ordinary function from X to the power set of Y, written as φ: X → 2Y, such that φ(x) is non-empty for every . Some prefer the term correspondence, which is used to refer to a functio
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https://en.wikipedia.org/wiki/Insertion
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Insertion may refer to:
Insertion (anatomy), the point of a tendon or ligament onto the skeleton or other part of the body
Insertion (genetics), the addition of DNA into a genetic sequence
Insertion, several meanings in medicine, see ICD-10-PCS
Insertion loss, in electronics
Insertion reaction, a chemical reaction in which one chemical entity interposes itself into an existing bond of a second chemical entity (e.g.: A + B–C → B–A–C)
Insertion sort, a simple computer algorithm for sorting arrays
Local insertion, in broadcasting
See also
Insert (disambiguation)
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https://en.wikipedia.org/wiki/Albert%20Shiryaev
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Albert Nikolayevich Shiryaev (; born October 12, 1934) is a Soviet and Russian mathematician. He is known for his work in probability theory, statistics and financial mathematics.
Career
He graduated from Moscow State University in 1957. From that time until now he has been working in Steklov Mathematical Institute. He earned his candidate degree in 1961 (Andrey Kolmogorov was his advisor) and a doctoral degree in 1967 for his work "On statistical sequential analysis". He is a professor of the department of mechanics and mathematics of Moscow State University, since 1971. Shiryaev holds a 20% permanent professorial position at the School of Mathematics, University of Manchester. He has supervised more than 50 doctoral dissertations and is the author or coauthor of more than 250 publications.
In 1970 he was an Invited Speaker with talk Sur les equations stochastiques aux dérivées partielles at the International Congress of Mathematicians (ICM) in Nice. In 1978 he was a Plenary Speaker with talk Absolute Continuity and Singularity of Probability Measures in Functional Spaces at the ICM in Helsinki.
He was elected in 1985 an honorary member of the Royal Statistical Society and in 1990 a member of Academia Europaea. From 1989 to 1991 he was the president of the Bernoulli Society for Mathematical Statistics and Probability. From 1994 to 1998 he was the president of the Russian Actuarial Society. In 1996 he was awarded a Humboldt Prize. He was elected a corresponding member o
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https://en.wikipedia.org/wiki/Power%20MOSFET
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A power MOSFET is a specific type of metal–oxide–semiconductor field-effect transistor (MOSFET) designed to handle significant power levels. Compared to the other power semiconductor devices, such as an insulated-gate bipolar transistor (IGBT) or a thyristor, its main advantages are high switching speed and good efficiency at low voltages. It shares with the IGBT an isolated gate that makes it easy to drive. They can be subject to low gain, sometimes to a degree that the gate voltage needs to be higher than the voltage under control.
The design of power MOSFETs was made possible by the evolution of MOSFET and CMOS technology, used for manufacturing integrated circuits since the 1960s. The power MOSFET shares its operating principle with its low-power counterpart, the lateral MOSFET. The power MOSFET, which is commonly used in power electronics, was adapted from the standard MOSFET and commercially introduced in the 1970s.
The power MOSFET is the most common power semiconductor device in the world, due to its low gate drive power, fast switching speed, easy advanced paralleling capability, wide bandwidth, ruggedness, easy drive, simple biasing, ease of application, and ease of repair. In particular, it is the most widely used low-voltage (less than 200 V) switch. It can be found in a wide range of applications, such as most power supplies, DC-to-DC converters, low-voltage motor controllers, and many other applications.
History
The MOSFET was invented by Mohamed Atalla and
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https://en.wikipedia.org/wiki/Stephen%20Fienberg
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Stephen Elliott Fienberg (27 November 1942 – 14 December 2016) was a Professor Emeritus (formerly the Maurice Falk University Professor of Statistics and Social Science) in the Department of Statistics, the Machine Learning Department, Heinz College, and Cylab at Carnegie Mellon University.
Fienberg was the founding co-editor of the Annual Review of Statistics and Its Application and of the Journal of Privacy and Confidentiality.
Early life and education
Born in Toronto, Ontario, Fienberg earned a Bachelor of Science degree in Mathematics and Statistics from the University of Toronto in 1964, a Master of Arts degree in Statistics in 1965, and a Ph.D. in Statistics in 1968 from Harvard University for research supervised by Frederick Mosteller.
Career and research
Fienberg was on the Carnegie Mellon University faculty from 1980 and served as Dean of the Dietrich College of Humanities and Social Sciences. He became a U.S. citizen in 1998.
Fienberg was one of the foremost social statisticians in the world, and was well known for his work in log-linear modeling for categorical data, the statistical analysis of network data, and methodology for disclosure limitation.
He was also an expert on forensic science, the only statistician to serve on the National Commission on Forensic Science.
He authored more than 400 publications, including six books, advised more than 30 Ph.D. students, and could claim more than 105 descendants in his mathematical genealogy.
His publications inc
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https://en.wikipedia.org/wiki/Taxonomy%20of%20the%20Cactaceae
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In 1984, the International Organization for Succulent Plant Study set up a working party, now called the International Cactaceae Systematics Group, to produce a consensus classification of the cactus family, down to the level of genus. Their classification has been used as the basis for systems published since the mid-1990s. Treatments in the 21st century have generally divided the family into around 125–130 genera and 1,400–1,500 species, which are then arranged in a number of tribes and subfamilies. However, subsequent molecular phylogenetic studies have shown that a very high proportion of the higher taxa (genera, tribes and subfamilies) are not monophyletic, i.e. they do not contain all of the descendants of a common ancestor. , the internal classification of the family Cactaceae remained uncertain and subject to change. A classification incorporating many of the insights from the molecular studies was produced by Nyffeler and Eggli in 2010.
Overview
The classification of the family Cactaceae remains uncertain . Since the mid-1990s, the system produced by the International Cactaceae Systematics Group (ICSG) of the International Organization for Succulent Plant Study has been used as the basis of many published classifications. Detailed treatments produced in the 21st century have divided the family into around 125–130 genera and 1,400–1,500 species, which are then arranged into a number of tribes and subfamilies.
The ICSG classification of the family recognizes four s
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https://en.wikipedia.org/wiki/Sine%20and%20cosine%20transforms
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In mathematics, the Fourier sine and cosine transforms are forms of the Fourier transform that do not use complex numbers or require negative frequency. They are the forms originally used by Joseph Fourier and are still preferred in some applications, such as signal processing or statistics.
Definition
The Fourier sine transform of , sometimes denoted by either or , is
If means time, then is frequency in cycles per unit time, but in the abstract, they can be any pair of variables which are dual to each other.
This transform is necessarily an odd function of frequency, i.e. for all :
The numerical factors in the Fourier transforms are defined uniquely only by their product. Here, in order that the Fourier inversion formula not have any numerical factor, the factor of 2 appears because the sine function has norm of
The Fourier cosine transform of , sometimes denoted by either or , is
It is necessarily an even function of frequency, i.e. for all :
Since positive frequencies can fully express the transform, the non-trivial concept of negative frequency needed in the regular Fourier transform can be avoided.
Simplification to avoid negative t
Some authors only define the cosine transform for even functions of , in which case its sine transform is zero. Since cosine is also even, a simpler formula can be used,
Similarly, if is an odd function, then the cosine transform is zero and the sine transform can be simplified to
Other conventions
Just like the Fourier
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https://en.wikipedia.org/wiki/Classification%20of%20discontinuities
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Continuous functions are of utmost importance in mathematics, functions and applications. However, not all functions are continuous. If a function is not continuous at a point in its domain, one says that it has a discontinuity there. The set of all points of discontinuity of a function may be a discrete set, a dense set, or even the entire domain of the function.
The oscillation of a function at a point quantifies these discontinuities as follows:
in a removable discontinuity, the distance that the value of the function is off by is the oscillation;
in a jump discontinuity, the size of the jump is the oscillation (assuming that the value at the point lies between these limits of the two sides);
in an essential discontinuity, oscillation measures the failure of a limit to exist; the limit is constant.
A special case is if the function diverges to infinity or minus infinity, in which case the oscillation
is not defined (in the extended real numbers, this is a removable discontinuity).
Classification
For each of the following, consider a real valued function of a real variable defined in a neighborhood of the point at which is discontinuous.
Removable discontinuity
Consider the piecewise function
The point is a removable discontinuity. For this kind of discontinuity:
The one-sided limit from the negative direction:
and the one-sided limit from the positive direction:
at both exist, are finite, and are equal to In other words, since the two one-sided limit
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https://en.wikipedia.org/wiki/The%20Lad%20from%20Old%20Ireland
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The Lad from Old Ireland, also called A Lad from Old Ireland, is a one-reel 1910 American motion picture directed by and starring Sidney Olcott and written by and co-starring Gene Gauntier. It was the first film appearance of prolific actor/director J.P. McGowan.
Production background
The film was the first ever production by an American movie studio to be filmed on location outside of the United States. Filming took place around Cork and Killarney in Ireland, and in New York City.
In August 1910, the Kalem Company of New York City sent director Sidney Olcott and a film crew to film in Europe. In Ireland, Olcott made The Lad From Old Ireland from a script written by Gene Gauntier. Shot by cinematographer George K. Hollister, the film was described in the publicity releases for its November premiere as "Kalem’s Great Trans-Atlantic Drama."
Laurene Santley doubles the Irish grandmother in the indoor sequence shot in the Kalem New York studio.
During that trip in Ireland Olcott shot a second film : The Irish Honeymoon.
Plot
An Irish boy (Olcott) emigrates to America to escape the desperate poverty of Ireland. After finding work in construction, he finds success in politics. He returns to Ireland after receiving a letter from his sweetheart (Gauntier) just as her destitute family is being forced off their land.
Cast
Sidney Olcott as Terry O'Connor
Gene Gauntier as Aileene
Thomas O'Connor as The landlord
Arthur Donaldson as Parish priest
J.P. McGowan as Election agent
Robert
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https://en.wikipedia.org/wiki/TN%20status
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TN status (or TN classification; "TN" from Trade NAFTA) is a special non-immigrant classification of foreign nationals in the United States, which offers expedited work authorization to a citizen of Canada or a national of Mexico. It was created as a result of provisions of the North American Free Trade Agreement that mandated simplified entry and employment permission for certain professionals from each of the three NAFTA member states in the other member states. The provisions of NAFTA relevant to TN status were then carried over almost verbatim to the United States–Mexico–Canada Agreement that replaced NAFTA in 2020.
A Canadian citizen or Mexican national with a job offer from a U.S. employer in certain defined professions and who meets the minimal education requirements for the relevant profession can work in the United States, for up to three years. The classification theoretically may be renewed indefinitely, although real-world complications may limit the number of times, or overall length of time, a foreign national might successfully be granted an authorized period of admission into the United States in the classification.
For Mexican nationals, being granted admission in TN classification generally requires first being issued a TN visa at a U.S. consular post. In contrast, Canadian citizens, who are generally exempt from the usual requirement of U.S. federal regulations to obtain a U.S. visa in advance of requesting admission to the U.S. (with limited exceptions),
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https://en.wikipedia.org/wiki/Galerkin%20method
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In mathematics, in the area of numerical analysis, Galerkin methods are named after the Soviet mathematician Boris Galerkin. They convert a continuous operator problem, such as a differential equation, commonly in a weak formulation, to a discrete problem by applying linear constraints determined by finite sets of basis functions.
Often when referring to a Galerkin method, one also gives the name along with typical assumptions and approximation methods used:
Ritz–Galerkin method (after Walther Ritz) typically assumes symmetric and positive definite bilinear form in the weak formulation, where the differential equation for a physical system can be formulated via minimization of a quadratic function representing the system energy and the approximate solution is a linear combination of the given set of the basis functions.
Bubnov–Galerkin method (after Ivan Bubnov) does not require the bilinear form to be symmetric and substitutes the energy minimization with orthogonality constraints determined by the same basis functions that are used to approximate the solution. In an operator formulation of the differential equation, Bubnov–Galerkin method can be viewed as applying an orthogonal projection to the operator.
Petrov–Galerkin method (after Georgii I. Petrov) allows using basis functions for orthogonality constraints (called test basis functions) that are different from the basis functions used to approximate the solution. Petrov–Galerkin method can be viewed as an extensio
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https://en.wikipedia.org/wiki/Poeciloneuron
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Poeciloneuron is a plant genus in the family Calophyllaceae. It contains a single species, Poeciloneuron indicum.
References
Monotypic Malpighiales genera
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https://en.wikipedia.org/wiki/Gujarati%20numerals
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Gujarati numerals is the numeral system of the Gujarati script of South Asia, which is a derivative of Devanagari numerals. It is the official numeral system of Gujarat, India. It is also officially recognized in India and as a minor script in Pakistan.
Digits
The following table shows Gujarati digits and the Gujarati word for each of them in various scripts.
{lang|gu|૧૨૩૫૭૦૩૬}} || 9 || || || nav ||
Larger numbers
Digits are combined to represent numbers larger than 9 as per the standard positional decimal rules.
See also
Gujarati script
Gurmukhi numerals
References
Numerals
Gujarati culture
External links
1 to 100 Gujarati Numbers and Words from English
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https://en.wikipedia.org/wiki/Rubiscolin
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The rubiscolins are a group of opioid peptides that are formed during digestion of the ribulose bisphosphate carboxylase/oxygenase (Rubisco) protein from spinach leaves. These peptides have much in common with the better-known gluten exorphins.
Types of Rubiscolin
There are 2 known rubiscolins with known structure:
Rubiscolin-5
Structure: H-Tyr-Pro-Leu-Asp-Leu-OH
Rubiscolin-6
Function: can have an anxiolytic effect via activation of sigma1 and dopamine D1 receptors.
Structure: H-Tyr-Pro-Leu-Asp-Leu-Phe-OH
Studies on Rubiscolin
Studies have been conducted on rubiscolin structure and biological responses following its digestion. The tertiary structure and biological function of spinach-derived rubiscolin has been analyzed in the laboratory. When rubiscolin is digested, studies have shown that rubiscolin has the potential to bind to δ opioid receptors in the body. The analysis of the amino acids responsible for this agonistic relationship of rubiscolin with δ opioid receptors can lead to replication of these proteins in the lab. Rubiscolin has the capability to bind to δ opioid receptors following its digestion. Upon the digestion of rubiscolin from spinach with the protease pepsin, peptides MRWRD, MRW, LRIPVA, AND IAYKPAG were found and purified. These peptides were found to have binding capabilities with angiotensin I-converting enzyme (ACE), which catalyze an antihypertensive, or decreased blood pressure, response. When treated to rats in the laboratory, MRW, MRWRD, and
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https://en.wikipedia.org/wiki/Richardson%E2%80%93Lucy%20deconvolution
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The Richardson–Lucy algorithm, also known as Lucy–Richardson deconvolution, is an iterative procedure for recovering an underlying image that has been blurred by a known point spread function. It was named after William Richardson and Leon B. Lucy, who described it independently.
Description
When an image is produced using an optical system and detected using photographic film or a charge-coupled device, for instance, it is inevitably blurred, with an ideal point source not appearing as a point but being spread out into what is known as the point spread function. Extended sources can be decomposed into the sum of many individual point sources, thus the observed image can be represented in terms of a transition matrix p operating on an underlying image:
where is the intensity of the underlying image at pixel and is the detected intensity at pixel . In general, a matrix whose elements are describes the portion of light from source pixel j that is detected in pixel i. In most good optical systems (or in general, linear systems that are described as shift invariant) the transfer function p can be expressed simply in terms of the spatial offset between the source pixel j and the observation pixel i:
where is called a point spread function. In that case the above equation becomes a convolution. This has been written for one spatial dimension, but of course most imaging systems are two dimensional, with the source, detected image, and point spread function all having two i
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https://en.wikipedia.org/wiki/MCL
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MCL may refer to:
Medicine
Mantle cell lymphoma
Mast cell leukemia
Medial collateral ligament
Medical Center Leeuwarden
Microlitre (μL), or microliter
Midclavicular line
Mucocutaneous leishmaniasis
Multiple cutaneous leiomyoma
Myeloid cell leukemia sequence 1 (MCL1)
Companies and organizations
MCL Cafeterias, a chain of American cafeteria-style restaurants
Mahanadi Coalfields Limited, a coal-producing company in India
Marine Corps League
Movement for Christian Liberation
Malabar Cements Limited a cement company in Kerala
Mysore Cements Limited a cement company
Law
Michigan Compiled Laws
Science, engineering and industry
Maximum Contaminant Level
Maximum Coupling Loss
Mid-Canada Line of early-warning radar stations
Computer Science and mathematics
1150 in Roman numerals
Macintosh Common Lisp
McLaughlin group (mathematics), a sporadic simple group
Monte Carlo localization
Multicollinearity
Sport
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https://en.wikipedia.org/wiki/FORMAC
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FORMAC, the FORmula MAnipulation Compiler, was the first computer algebra system to have significant use. It was developed by Jean E. Sammet and her team, as an extension of FORTRAN IV. The compiler was implemented as a preprocessor taking the FORMAC program and converting it to a FORTRAN IV program which was in turn compiled without further user intervention.
Initial development started in 1962 and was complete by April 1964. In November it was released to IBM customers.
FORMAC supported computation, manipulation, and use of symbolic expressions. In addition it supported rational arithmetic.
See also
ALTRAN
References
Bibliography
External links
Computer algebra systems
Fortran programming language family
Procedural programming languages
Programming languages created in 1962
Programming languages created by women
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https://en.wikipedia.org/wiki/Allophane
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Allophane is an amorphous to poorly crystalline hydrous aluminium silicate clay mineraloid. Its chemical formula is Al2O3·(SiO2)1.3-2·(2.5-3)H2O. Since it has short-range atomic order, it is a mineraloid, rather than a mineral, and can be identified by its distinctive infrared spectrum and its X-ray diffraction pattern. It was first described in 1816 in Gräfenthal, Thuringia, Germany. Allophane is a weathering or hydrothermal alteration product of volcanic glass and feldspars and sometimes has a composition similar to kaolinite but generally has a molar ratio of Al:Si = 2. It typically forms under mildly acidic to neutral pH (5–7). Its structure has been debated, but it is similar to clay minerals and is composed of curved alumina octahedral and silica tetrahedral layers. Transmission electron micrographs show that it is generally made up of aggregates of hollow spherules ~3–5 nm in diameter. Allophane can alter to form halloysite under resilicating aqueous conditions and can alter to form gibbsite under desilicating conditions. A copper-containing variety cupro-allophane has been reported.
It forms waxy botryoidal to crusty masses with color varying from white through green, blue, yellow, to brown. It has a Mohs hardness of 3 and a specific gravity of 1.0.
It was named from the Greek allos – "other" and phanos – "to appear", as it gave a deceptive reaction in the blowpipe flame in old mineralogical testing.
References
Webmineral data
Mindat
Handbook of Mineralogy
Wad
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https://en.wikipedia.org/wiki/CZT
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CZT may stand for:
Community Z Tools, a set of tools for the Z notation
Cadmium zinc telluride, a semiconductor material
Chirp_Z-transform, another name for Bluestein's FFT algorithm
Changzhutan, Changsha-Zhuzhou-xiangTan City Cluster
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https://en.wikipedia.org/wiki/California%20Fuel%20Cell%20Partnership
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The California Fuel Cell Partnership (CaFCP) is a public-private partnership to promote hydrogen vehicles (including cars and buses) in California. It is notable as one of the first initiatives for that purpose undertaken in the United States. The challenge is which come first, hydrogen cars or filling stations.
In January 1995, three state government agencies—California Air Resources Board, South Coast Air Quality Management District and California Energy Commission joined with six private sector companies—Ballard Power Systems, DaimlerChrysler, Ford, BP, Shell Hydrogen and ChevronTexaco—to form the California Fuel Cell Partnership. The goal was to demonstrate and promote the potential for fuel cell vehicles (FCV) as a clean, safe, and practical alternative to vehicles powered by internal combustion engines.
In November 2000, the West Sacramento headquarters opened. The building includes a public gallery, offices, a hydrogen fueling station and indoor service bays for vehicle maintenance. At first, the automakers had just handful of cars all stationed in Sacramento. The goal was to see if these vehicles and fuel could be technically viable. If the answer was no, then CaFCP would close its doors in 2004.
Before the first phase was finished, CaFCP members knew that the technology could succeed. The number of members grew to 33 and set a new set of goals for the next phase of operation, from 2004-2007. During this period, CaFCP members worked on project to prove or disprove
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https://en.wikipedia.org/wiki/Pulsed-field%20gel%20electrophoresis
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Pulsed-field gel electrophoresis (PFGE) is a technique used for the separation of large DNA molecules by applying to a gel matrix an electric field that periodically changes direction. Pulsed-field gel electrophoresis is a method used to separate large segments of DNA using an alternating and cross field. In a uniform magnetic field, components larger than 50kb move through the gel in a zigzag pattern, allowing for more effective separation of DNA molecules. This method is commonly used in microbiology for typing bacteria and is a valuable tool for epidemiological studies and gene mapping in microbes and mammalian cells. It also played a role in the development of large-insert cloning systems such as bacterial and yeast artificial chromosomes.
PFGE can be used to determine the genetic similarity between bacteria, as close and similar species will have similar profiles while dissimilar ones will have different profiles. This feature is useful in identifying the prevalent agent of a disease. Additionally, it can be used to monitor and evaluate micro-organisms in clinical samples, soil and water. It is also considered a reliable and standard method in vaccine preparation. In recent years, PFGE has been widely used as a powerful tool for controlling, preventing and monitoring diseases in different populations
Discovery
The discovery of PFGE can be traced back to the late 1970s and early 1980s. One of the earliest references to the use of PFGE for DNA analysis is a 1977 paper b
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https://en.wikipedia.org/wiki/Semicubical%20parabola
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In mathematics, a cuspidal cubic or semicubical parabola is an algebraic plane curve that has an implicit equation of the form
(with ) in some Cartesian coordinate system.
Solving for leads to the explicit form
which imply that every real point satisfies . The exponent explains the term semicubical parabola. (A parabola can be described by the equation .)
Solving the implicit equation for yields a second explicit form
The parametric equation
can also be deduced from the implicit equation by putting
The semicubical parabolas have a cuspidal singularity; hence the name of cuspidal cubic.
The arc length of the curve was calculated by the English mathematician William Neile and published in 1657 (see section History).
Properties of semicubical parabolas
Similarity
Any semicubical parabola is similar to the semicubical unit parabola
Proof: The similarity (uniform scaling) maps the semicubical parabola onto the curve with
Singularity
The parametric representation is regular except at point At point the curve has a singularity (cusp). The proof follows from the tangent vector Only for this vector has zero length.
Tangents
Differentiating the semicubical unit parabola one gets at point of the upper branch the equation of the tangent:
This tangent intersects the lower branch at exactly one further point with coordinates
(Proving this statement one should use the fact, that the tangent meets the curve at twice.)
Arclength
Determining the arclength
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https://en.wikipedia.org/wiki/Pythagorean%20prime
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A Pythagorean prime is a prime number of the Pythagorean primes are exactly the odd prime numbers that are the sum of two squares; this characterization is Fermat's theorem on sums of two squares.
Equivalently, by the Pythagorean theorem, they are the odd prime numbers for which is the length of the hypotenuse of a right triangle with integer legs, and they are also the prime numbers for which itself is the hypotenuse of a primitive Pythagorean triangle. For instance, the number 5 is a Pythagorean prime; is the hypotenuse of a right triangle with legs 1 and 2, and 5 itself is the hypotenuse of a right triangle with legs 3 and 4.
Values and density
The first few Pythagorean primes are
By Dirichlet's theorem on arithmetic progressions, this sequence is infinite. More strongly, for each , the numbers of Pythagorean and non-Pythagorean primes up to are approximately equal. However, the number of Pythagorean primes up to is frequently somewhat smaller than the number of non-Pythagorean primes; this phenomenon is known as For example, the only values of up to 600000 for which there are more Pythagorean than non-Pythagorean odd primes less than or equal to n are 26861
Representation as a sum of two squares
The sum of one odd square and one even square is congruent to 1 mod 4, but there exist composite numbers such as 21 that are and yet cannot be represented as sums of two squares. Fermat's theorem on sums of two squares states that the prime numbers that can be re
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https://en.wikipedia.org/wiki/Fin%20%28disambiguation%29
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A fin is an appendage used to produce lift and thrust or to steer while traveling in water, air, or other fluid media.
Fin, FIN, or Fins may also refer to:
Biology
Fish fin, an anatomical feature of fish
Fin fish, fish that possess fins
Fin whale (Balaenoptera physalus)
People
Fín (died 604), Gaelic princess, wife of Oswiu of Northumbria
Finns, people from Finland
Fin Bartels (born 1987), German football midfielder
Fin Donnelly (born 1966), Canadian politician
Fin Dow-Smith, (born 1988), British songwriter
Fin Leavell, American musician
Fin Taylor, (born 1990), English stand-up comedian
Fin Wilson (1888–1959), American professional baseball pitcher
Henri Fin (born 1950), French cyclist
Legendary and fictional characters
Fin (comics), the name of two characters from Marvel Comics
Fin (troll), in Danish legend
Fin the Whale, the mascot of the Vancouver Canucks
Fin Tutuola, a fictional character on the TV drama Law & Order: Special Victims Unit
Places
Fin, Iran, a city
Fins, Somme, a commune in France
Fin District, Iran
Fin Garden, in Kashan, Iran
Fin Island, in British Columbia, Canada
Fin Rural District, Iran
Finland
Music
Fin (band), an English indie rock band
Fin (John Talabot album), 2012
Fin (Syd album), 2017
"Fin" (song), a 2006 song by Supergrass
"Fin", 1986 song by Akina Nakamori
"Fin", by Christie Front Drive from Christie Front Drive, 1997
"Fin", a song by Nebula from the 2003 album Atomic Ritual
"Fins" (song), a 1979 song by
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https://en.wikipedia.org/wiki/11%CE%B2-Hydroxysteroid%20dehydrogenase
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11β-Hydroxysteroid dehydrogenase (HSD-11β or 11β-HSD) enzymes catalyze the conversion of inert 11 keto-products (cortisone) to active cortisol, or vice versa, thus regulating the access of glucocorticoids to the steroid receptors.
The human genome encodes two distinct HSD-11β isozymes (HSD-11β Type 1 and HSD-11β Type 2) on distinct genes. The dehydrogenase activity of a HSD-11β converts a 11beta-hydroxysteroid to the corresponding 11-oxosteroid by reducing NADP+ or NAD+. HSD-11βs are part of the larger class of oxidoreductases and HSD-11β Type 1 has oxidoreductase activity (the reverse of dehydrogenase activity). HSD-11βs participate in c21-steroid hormone metabolism and androgen and estrogen metabolism.
Structural studies
Several structures for HSD-11β Type 1 have been solved to date with various mutations and inhibitors. There are no known structures for HSD-11β Type 2.
Function
Cortisol, a glucocorticoid, binds the glucocorticoid receptor. However, because of its molecular similarity to aldosterone it also binds the mineralcorticoid receptor at higher concentrations. Both aldosterone and cortisol have a similar affinity for the mineralocorticoid receptor; however, there is vastly more cortisol in circulation than aldosterone. To prevent over-stimulation of the mineralocorticoid receptor by cortisol, HSD-11βs convert the biologically active cortisol to the inactive cortisone, which can no longer bind the mineralocorticoid receptor. HSD-11βs co-localizes with intracell
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https://en.wikipedia.org/wiki/Uniclass
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Uniclass 2015 is a unified classification system for all sectors of the UK construction industry. It contains consistent tables classifying items of all scales, from entire systems such as a railway to individual product items such as anchor plates, flue liners or LED lamps.
Originally released in 1997, Uniclass allowed project information to be structured to a recognised standard. The original version was later heavily revised, to make it more suitable for use with modern construction industry practice, and to make it compatible with Building information modeling (BIM) processes.
History
Uniclass was created in 1997 by the Construction Project Information Committee (CPIC), a UK industry organisation with representatives from key institutions including the Royal Institute of British Architects and the Royal Institution of Chartered Surveyors. A voluntary standard classification system for the construction industry, it was intended to help organise information throughout design and construction processes. A standard classification facilitates interoperability between different systems.
Early versions were criticised for not being unified, for inconsistencies between the labelling and depth of tables, for poor integration of civil engineering and building works, and for being an essentially paper-based system. Uniclass 1.4 was superseded by Uniclass 2 in 2013.
Uniclass 2015 development
Led by the National Building Specification (NBS), experts from across the industry develo
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https://en.wikipedia.org/wiki/Homeobox%20protein%20NANOG
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Homeobox protein NANOG (hNanog) is a transcriptional factor that helps embryonic stem cells (ESCs) maintain pluripotency by suppressing cell determination factors. hNanog is encoded in humans by the NANOG gene. Several types of cancer are associated with NANOG.
Etymology
The name NANOG derives from Tír na nÓg (Irish for "Land of the Young"), a name given to the Celtic Otherworld in Irish and Scottish mythology.
Structure
The human hNanog protein coded by the NANOG gene, consists of 305 amino acids and possesses 3 functional domains: the N-terminal domain, the C- terminal domain, and the conserved homeodomain motif. The homeodomain region facilitates DNA binding. The NANOG is located on chromosome 12, and the mRNA contains a 915 bp open reading frame (ORF) with 4 exons and 3 introns.
The N-terminal region of hNanog is rich in serine, threonine and proline residues, and the C-terminus contains a tryptophan-rich domain. The homeodomain in hNANOG ranges from residues 95 to 155. There are also additional NANOG genes (NANOG2, NANOG p8) which potentially affect ESCs' differentiation. Scientists have shown that NANOG is fundamental for self-renewal and pluripotency, and NANOG p8 is highly expressed in cancer cells.
Function
NANOG is a transcription factor in embryonic stem cells (ESCs) and is thought to be a key factor in maintaining pluripotency. NANOG is thought to function in concert with other factors such as POU5F1 (Oct-4) and SOX2 to establish ESC identity. These cells
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https://en.wikipedia.org/wiki/Ecotoxicology
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Ecotoxicology is the study of the effects of toxic chemicals on biological organisms, especially at the population, community, ecosystem, and biosphere levels. Ecotoxicology is a multidisciplinary field, which integrates toxicology and ecology.
The ultimate goal of ecotoxicology is to reveal and predict the effects of pollution within the context of all other environmental factors. Based on this knowledge the most efficient and effective action to prevent or remediate any detrimental effect can be identified. In those ecosystems that are already affected by pollution, ecotoxicological studies can inform the choice of action to restore ecosystem services, structures, and functions efficiently and effectively.
Ecotoxicology differs from environmental toxicology in that it integrates the effects of stressors across all levels of biological organisation from the molecular to whole communities and ecosystems, whereas environmental toxicology includes toxicity to humans and often focuses upon effects at the organism level and below.
History
Ecotoxicology is a relatively young discipline that made its debuts in the 1970s in the realm of the environmental sciences. Its methodological aspects, derived from toxicology, are widened to encompass the human environmental field and the biosphere at large. While conventional toxicology limits its investigations to the cellular, molecular and organismal scales, ecotoxicology strives to assess the impact of chemical, physicochemical and bi
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https://en.wikipedia.org/wiki/DPLL
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DPLL stands for:
DPLL algorithm, for solving the boolean satisfiability problem
Digital phase-locked loop, an electronic feedback system that generates a signal
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https://en.wikipedia.org/wiki/Electrophoresis%20%28disambiguation%29
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Electrophoresis is the motion of dispersed particles relative to a fluid under the influence of a spatially uniform electric field.
"Electrophoresis" can also refer to:
Interface and colloid science
Dielectrophoresis, similar motion in a space non-uniform electric field
Microelectrophoresis, a method of studying electrophoresis of various dispersed particles using optical microscopy
Electrophoretic light scattering, a method for measuring electrophoretic mobility based on dynamic light scattering
Molecular biology and biochemistry
Affinity electrophoresis, used to separate and characterize biomolecules on basis of their molecular characteristics through binding to another biomolecule
Capillary electrophoresis, commonly used to separate biomolecules by their charge and frictional forces
Gel electrophoresis, a technique used by scientists to separate molecules based on physical characteristics such as size, shape, or isoelectric point
electrophoresis of nucleic acids, a specific type of gel electrophoresis used to analyse DNA and RNA
electrophoresis of proteins, a specific type of gel electrophoresis used to analyse proteins
two-dimensional electrophoresis, a specific type of gel electrophoresis commonly used to analyse proteins which involves two separation mechanisms to separate molecules
SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electrophoresis, commonly used to analyse proteins
Immunoelectrophoresis, used to separate and characterize biomolecules on basis thei
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https://en.wikipedia.org/wiki/Extremal%20combinatorics
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Extremal combinatorics is a field of combinatorics, which is itself a part of mathematics. Extremal combinatorics studies how large or how small a collection of finite objects (numbers, graphs, vectors, sets, etc.) can be, if it has to satisfy certain restrictions.
Much of extremal combinatorics concerns classes of sets; this is called extremal set theory. For instance, in an n-element set, what is the largest number of k-element subsets that can pairwise intersect one another? What is the largest number of subsets of which none contains any other? The latter question is answered by Sperner's theorem, which gave rise to much of extremal set theory.
Another kind of example: How many people can be invited to a party where among each three people there are two who know each other and two who don't know each other? Ramsey theory shows that at most five persons can attend such a party. Or, suppose we are given a finite set of nonzero integers, and are asked to mark as large a subset as possible of this set under the restriction that the sum of any two marked integers cannot be marked. It appears that (independent of what the given integers actually are) we can always mark at least one-third of them.
See also
Extremal graph theory
Sauer–Shelah lemma
Erdős–Ko–Rado theorem
Kruskal–Katona theorem
Fisher's inequality
Union-closed sets conjecture
References
.
.
.
Combinatorial optimization
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https://en.wikipedia.org/wiki/Gene%20Roberts
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Gene Roberts may refer to:
Gene Roberts (journalist) (born 1932), American editor and professor of journalism
Gene Roberts (American football) (1923–2009), American football running back
Meg Randall (1926–2018), American actress, credited as Gene Roberts before 1949
Gene Roberts, former mayor of Chattanooga, Tennessee
Gene Roberts, NASCAR Winston Cup Series crew chief for Melling Racing during the 1992 season
See also
Eugene Roberts (disambiguation)
Jean Roberts (born 1943), Australian athlete in the shot put and discus
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https://en.wikipedia.org/wiki/Retinotopy
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Retinotopy (from Greek τόπος, place) is the mapping of visual input from the retina to neurons, particularly those neurons within the visual stream. For clarity, 'retinotopy' can be replaced with 'retinal mapping', and 'retinotopic' with 'retinally mapped'.
Visual field maps (retinotopic maps) are found in many amphibian and mammalian species, though the specific size, number, and spatial arrangement of these maps can differ considerably. Sensory topographies can be found throughout the brain and are critical to the understanding of one's external environment. Moreover, the study of sensory topographies and retinotopy in particular has furthered our understanding of how neurons encode and organize sensory signals.
Retinal mapping of the visual field is maintained through various points of the visual pathway including but not limited to the retina, the dorsal lateral geniculate nucleus, the optic tectum, the primary visual cortex (V1), and higher visual areas (V2-V4). Retinotopic maps in cortical areas other than V1 are typically more complex, in the sense that adjacent points of the visual field are not always represented in adjacent regions of the same area. For example, in the second visual area (V2), the map is divided along an imaginary horizontal line across the visual field, in such a way that the parts of the retina that respond to the upper half of the visual field are represented in cortical tissue that is separated from those parts that respond the lower half of
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https://en.wikipedia.org/wiki/XploRe
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XploRe was a commercial statistics software package, developed by the German software company MD*Tech around Prof. Dr. Wolfgang Härdle. XploRe has been discontinued in 2008, the last version, 4.8, is available for download at no cost. The user interacted with the software via the XploRe programming language, which is derived from the C programming language. Individual XploRe programs were called Quantlets.
Functions
Besides the standard functions for one- and multidimensional data analysis the focus was on non- and semiparametric modelling and the statistics of financial markets.
Kernel density estimation and regression (kernel regression)
Single index models
Generalized linear and additive models (GLM and GAM)
Value at risk (VaR) and implied volatilities
XploRe Quantlet Client
With the XploRe Quantlet Client users were able to run XploRe as Java applet in a web browser. The applet sent the user commands via a TCP/IP based communication protocol to the XploRe Quantlet Server, which computed the necessary results and sent them back to the client.
This technology was also used to enrich (electronic) books with interactive examples.
See also
Comparison of statistical packages
Literature
Härdle, Klinke, Müller. XploRe Learning Guide. Springer.
Härdle, Klinke, Müller. XploRe Applications Guide. Springer.
External links
Discontinued software
Windows-only freeware
Statistical programming languages
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https://en.wikipedia.org/wiki/Caesium%20perchlorate
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Caesium perchlorate or cesium perchlorate (CsClO4), is a perchlorate of caesium. It forms white crystals, which are sparingly soluble in cold water and ethanol. It dissolves more easily in hot water.
CsClO4 is the second least soluble of the alkali metal perchlorates (after Fr, followed by Rb, K, Li, and Na), a property which may be used for separatory purposes and even for gravimetric analysis. This low solubility played an important role in the characterization of francium as an alkali metal, as francium perchlorate coprecipitates with caesium perchlorate.
When heated, CsClO4 decomposes to caesium chloride above 250 °C. Like all perchlorates, it is a strong oxidant and may react violently with reducing agents and organic materials, especially at elevated temperatures.
References
External links
Sigma-Aldrich MSDS
Caesium compounds
Perchlorates
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https://en.wikipedia.org/wiki/Alchemy%20%28processor%29
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Alchemy is a family of ultra low power embedded microprocessors originally designed by Alchemy Semiconductor for communication and media devices. Alchemy processors are SoCs integrating a CPU core, a memory controller, and a varying set of peripherals. All members of the family use the Au1 CPU core implementing the MIPS32 instruction set by MIPS Technologies.
History
Alchemy Semiconductor was a fabless semiconductor company based in Austin, Texas. Founded in 1999 with a seed investment by Cadence Design Systems it licensed the 32-bit MIPS architecture to design, develop, and market high performance, ultra low power SoCs for the Internet Edge Device market. Peripherals were licensed from third parties. The founding team included former members of DEC's Austin Research and Design Center working on the StrongARM project, dissolved after DEC sold its microprocessors business to Intel. In May 2000 Alchemy Semiconductor became an independent company.
Alchemy Semiconductor unveiled the first member of the family, the Au1000 processor, at the Embedded Processor Forum in San Jose, CA, on June 13, 2000, with limited customer sampling in February 2001 and availability in production quantities in Q2 of that year, followed in 2001 and 2002 by the Au1500 and Au1100.
In February 2002 AMD acquired Alchemy in order to compete with Intel's ARM-based XScale processors, successor to the StrongARM line. They expanded the family with the Au1550 Security Network Processor and the Au1200 process
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https://en.wikipedia.org/wiki/I%20Married%20a%20Monster%20from%20Outer%20Space
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I Married a Monster from Outer Space is a 1958 American horror science fiction film from Paramount Pictures, produced and directed by Gene Fowler Jr., that stars Tom Tryon and Gloria Talbott. Paramount released the film as a double feature with The Blob.
The film's storyline concerns a young wife who begins to realize that her husband is not the man he was before they married. He has lost all real affection for her and for his new pet dog, which she gave him as a present. Thereafter, she quickly discovers that he is not the only man in town that appears to have changed. Now suspicious, she follows him one evening when he goes out for a walk and shockingly discovers that her husband is actually an alien humanoid.
Plot
After a year of marriage, Marge Farrell (Gloria Talbott) is despondent that her husband Bill (Tom Tryon) is cold and not acting toward her the way he did before they were married. He doesn't show any signs of genuine affection towards her or toward his new dog, a surprise anniversary present from Marge. The dog barks and snarls at him whenever he approaches; he kills it in their basement, telling Marge the dog was strangled by his collar while pulling on his tethered leash. She is also becoming concerned because, wanting a family, she has not become pregnant. After undergoing various tests, her doctor assures her that she can have children; he suggests that Bill come in and see him to be tested.
She soon notices that other husbands in their social circle are a
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https://en.wikipedia.org/wiki/Faddeev%20equations
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The Faddeev equations, named after their inventor Ludvig Faddeev, are equations that describe, at once, all the possible exchanges/interactions in a system of three particles in a fully quantum mechanical formulation. They can be solved iteratively.
In general, Faddeev equations need as input a potential that describes the interaction between two individual particles. It is also possible to introduce a term in the equation in order to take also three-body forces into account.
The Faddeev equations are the most often used non-perturbative formulations of the quantum-mechanical three-body problem.
Unlike the three body problem in classical mechanics, the quantum three body problem is uniformly soluble.
In nuclear physics, the off the energy shell nucleon-nucleon interaction has been studied by analyzing (n,2n) and (p,2p) reactions on deuterium targets, using the Faddeev Equations. The nucleon-nucleon interaction is expanded (approximated) as a series of separable potentials. The Coulomb interaction between two protons is a special problem, in that its expansion in separable potentials does not converge, but this is handled by matching the Faddeev solutions to long range Coulomb solutions, instead of to plane waves.
Separable potentials are interactions that do not preserve a particle's location. Ordinary local potentials can be expressed as sums of separable potentials. The physical nucleon-nucleon interaction, which involves exchange of mesons, is not expected to be
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https://en.wikipedia.org/wiki/Besian%20Idrizaj
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Besian Idrizaj (12 October 1987 – 15 May 2010) was an Austrian professional footballer. He also played in the Football League for Crystal Palace and Luton Town both whilst on loan from Liverpool for whom he did not make a League appearance. He also played for LASK Linz, Wacker Innsbruck and FC Eilenburg. He died of a heart attack on 15 May 2010 at the age of 22. He was of Albanian descent.
Career
Beginnings
Idrizaj started his career with Admira Linz and LASK Linz. He was Austria's young player of the year in the 2004–05 season.
Liverpool
He signed for Liverpool from LASK in the summer of 2005 on a two-year contract, following a trial spell.
At the time, he declared "I have always been a Liverpool fan and it is a dream come true to play for them. If you get a chance to go to Liverpool on trial then you have to take it. You cannot ignore a trial with the reigning Champions League winners. I would even have swum across the channel just to take part."
His 2005–06 season was interrupted by injuries. However, Idrizaj was expected to be a regular member of Gary Ablett and Hughie McAuley's reserve squad for the 2006–07 season. He made his debut for the first team in a pre-season friendly against Wrexham on 15 July 2006, playing for the first 45 minutes upfront as a striker, alongside fellow debutant Craig Bellamy.
After going on loan to Luton Town in 2007 he returned to Liverpool for the close season. On 7 July 2007, Idrizaj scored a hat trick in a friendly for the Reds agains
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https://en.wikipedia.org/wiki/Star%20Trek%3A%20Challenger
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Star Trek: Challenger is a spin-off series of Star Trek novels published by Pocket Books in the United States as part of Pocket's line. Based on the titular TV series created by Gene Roddenberry, the series was created by Pocket editor John J. Ordover and writer Diane Carey, and was a continuation of the six-book storyline, Star Trek: New Earth. The sixth and final New Earth book was subtitled Challenger, and served as a springboard for Star Trek: Challenger. It was published on August 1, 2000.
Premise
The New Earth novel Challenger features the survivors of a destroyed starship's crew constructing and launching a new starship in a far-off colony area that is vital for the continuance of the Federation.
Books
New Earth
Star Trek: New Earth: Wagon Train to the Stars by Diane Carey
Star Trek: New Earth: Belle Terre by Dean Wesley Smith with Diane Carey
Star Trek: New Earth: Rough Trails by L.A. Graf
Star Trek: New Earth: The Flaming Arrow by Kathy Oltion and Jerry Oltion
Star Trek: New Earth: Thin Air by Kristine Kathryn Rusch and Dean Wesley Smith
Star Trek: New Earth: Challenger by Diane Carey
Challenger
Gateways #2: Chainmail by Diane Carey
Gateways #7: What Lay Beyond (anthology) by Diane Carey, Peter David, Keith R.A. DeCandido, Christie Golden, Robert Greenberger, and Susan Wright
Main characters
New Earth
Rear Admiral James T. Kirk
Commander Spock
Doctor Leonard McCoy
Commander Montgomery Scott
Lieutenant Commander Hikaru Sulu
Lieutenant Pavel Cheko
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https://en.wikipedia.org/wiki/Black%20Widow%20%28video%20game%29
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Black Widow is a multidirectional shooter developed by Atari, Inc. and released in arcades in 1982. The game uses color vector graphics. The player controls a black widow spider via two joysticks, one to move and one to fire, defending the web from insects.
Black Widow was offered as a conversion kit for Gravitar (1982), a game which was not commercially successful. The kit uses the original Gravitar PCB with a few modifications and a new set of ROM chips. Many factory-built Black Widow machines were produced using unsold Gravitar cabinets with Black Widow side-art applied over the Gravitar sideart.
Gameplay
To destroy certain enemies, the player must lure other enemies into destroying them. There is also the Bug Slayer, a bug that helps the player eliminate enemies, with only loss of potential points being the only consequence. The Bug Slayer can help the player in tough situations, but can also prevent the player from achieving the number of extra lives necessary to endure later, more difficult, rounds.
Other enemies appear on the playing field as eggs, laid by other enemies. The player can move these eggs off the playing field to both eliminate the enemy and receive points, before it reaches maturity.
Enemies and Scoring
Mosquito - If shot, becomes '$'.
Beetle - Eats '$', but if shot, becomes '$'.
Hornet - Lays an egg on '$', but if shot, becomes '$'.
Egg - Grows to become hornet or spoiler. Must be pushed off the web to score 500, 1000, 1500, 2000, or even 2500
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https://en.wikipedia.org/wiki/Bel%20decomposition
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In semi-Riemannian geometry, the Bel decomposition, taken with respect to a specific timelike congruence, is a way of breaking up the Riemann tensor of a pseudo-Riemannian manifold into lower order tensors with properties similar to the electric field and magnetic field. Such a decomposition was partially described by Alphonse Matte in 1953 and by Lluis Bel in 1958.
This decomposition is particularly important in general relativity. This is the case of four-dimensional Lorentzian manifolds, for which there are only three pieces with simple properties and individual physical interpretations.
Decomposition of the Riemann tensor
In four dimensions the Bel decomposition of the Riemann tensor, with respect to a timelike unit vector field , not necessarily geodesic or hypersurface orthogonal, consists of three pieces:
the electrogravitic tensor
Also known as the tidal tensor. It can be physically interpreted as giving the tidal stresses on small bits of a material object (which may also be acted upon by other physical forces), or the tidal accelerations of a small cloud of test particles in a vacuum solution or electrovacuum solution.
the magnetogravitic tensor
Can be interpreted physically as a specifying possible spin-spin forces on spinning bits of matter, such as spinning test particles.
the topogravitic tensor
Can be interpreted as representing the sectional curvatures for the spatial part of a frame field.
Because these are all transverse (i.e. projected to the
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https://en.wikipedia.org/wiki/Transketolase
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Transketolase (abbreviated as TK) is an enzyme that, in humans, is encoded by the TKT gene. It participates in both the pentose phosphate pathway in all organisms and the Calvin cycle of photosynthesis. Transketolase catalyzes two important reactions, which operate in opposite directions in these two pathways. In the first reaction of the non-oxidative pentose phosphate pathway, the cofactor thiamine diphosphate accepts a 2-carbon fragment from a 5-carbon ketose (D-xylulose-5-P), then transfers this fragment to a 5-carbon aldose (D-ribose-5-P) to form a 7-carbon ketose (sedoheptulose-7-P). The abstraction of two carbons from D-xylulose-5-P yields the 3-carbon aldose glyceraldehyde-3-P. In the Calvin cycle, transketolase catalyzes the reverse reaction, the conversion of sedoheptulose-7-P and glyceraldehyde-3-P to pentoses, the aldose D-ribose-5-P and the ketose D-xylulose-5-P.
The second reaction catalyzed by transketolase in the pentose phosphate pathway involves the same thiamine diphosphate-mediated transfer of a 2-carbon fragment from D-xylulose-5-P to the aldose erythrose-4-phosphate, affording fructose 6-phosphate and glyceraldehyde-3-P. Again, in the Calvin cycle exactly the same reaction occurs, but in the opposite direction. Moreover, in the Calvin cycle this is the first reaction catalyzed by transketolase, rather than the second.
In mammals, transketolase connects the pentose phosphate pathway to glycolysis, feeding excess sugar phosphates into the main carbohydra
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https://en.wikipedia.org/wiki/Herbert%20Sichel
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Herbert Sichel (1915–1995) was a statistician who made great advances in the areas of both theoretical and applied statistics.
He developed the Sichel-t estimator for the log-normal distribution's t-statistic. He also made great leaps in the area of the generalized inverse Gaussian distribution, the mixture of which with the Poisson distribution became known as the Sichel distribution.
Dr Sichel pioneered the science of geostatistics with Danie Krige in the early 1950s. Sichel also was well recognised in the field of statistical linguistics.
He established the Operational Research Bureau in 1952. He was appointed as professor in Statistics and Operations Research in the Graduate Business School of the University of the Witwatersrand. He has been recognized as "one of the grand old men of the SA Statistical Association". In 1958 he was elected as a Fellow of the American Statistical Association.
The Herbert Sichel medal was established in 1997 and is awarded annually to the best statistics paper published in a South African journal in the previous year.
References
External links
https://web.archive.org/web/20060923050607/http://saturn.cs.unp.ac.za/~orssa/history_content.htmVarious historical references
Practical applications of some of Dr Sichel's work
South African statisticians
Operations researchers
1915 births
1995 deaths
South African scientists
Fellows of the American Statistical Association
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https://en.wikipedia.org/wiki/DDO
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DDO may refer to:
Science and technology
David Dunlap Observatory Catalogue, a catalogue of dwarf galaxies that was published in 1959
DDO (gene), that encodes the D-aspartate oxidase enzyme
Distant detached objects, class of minor planets in the outer reaches of the Solar System
Dynamic Drive Overlay, a software technique to extend a system BIOS
Games
Dungeons & Dragons Online, a massively multiplayer online role-playing game
Titles
Deputy Director for Operations, particularly as the title of a specific CIA official; cf. article
The above title is sometimes incorrectly rendered as Deputy Director of Operations; especially this latter term is also in generic use as the title of officials in business or other organizations.
Director of Operations, particularly in francophone environments, from the French Directeur Des Opérations.
Diocesan Director of Ordinands, a priest in a Church of England diocese overseeing the ordination process
Other
DDO Artists Agency, a talent agency
Dollard-des-Ormeaux, on-island suburb of Montreal in southwestern Quebec, Canada
Tsez language, by ISO 639-3 code
Den Danske Ordbog, a dictionary of Danish
Davao de Oro
See also
|
https://en.wikipedia.org/wiki/Moskva-class%20helicopter%20carrier
|
The Moskva class, Soviet designation Project 1123 Kondor (condor) and S-703 Project 1123M Kiev, was the first class of operational aircraft carriers (helicopter cruisers in the Soviet classification) built by the Soviet Union for the Soviet Navy.
These ships were laid down at Nikolayev South (Shipyard No.444). The lead vessel was launched in 1965 and named (); she entered service two years later. Moskva was followed by (, which was commissioned in late 1968; there were no further vessels built, reportedly due to the poor handling of the ships in rough seas. Both were conventionally powered.
The Moskvas were not true "aircraft carriers" in that they did not carry any fixed-wing aircraft; the air wing was composed entirely of helicopters. They were designed primarily as anti-submarine warfare (ASW) vessels, and her weapons and sensor suite was optimized against the nuclear submarine threat. Their strategic role was to defend the Soviet ballistic missile submarine bastions against incursions by Western attack submarines, forming the flagships of an ASW task force.
Design
The operational requirement was issued by Admiral Sergey Gorshkov in 1959. The aim of the ships was to counter NATO Polaris submarines and act as a flagship for anti-submarine warfare. Initially it was hoped to operate ten helicopters from an 8000-ton ship. The design evolved into a larger vessel capable of operating up to 14 helicopters with self defence armament.
Armament
Shipboard ASW armament include
|
https://en.wikipedia.org/wiki/Jean%20Trembley
|
Jean Trembley (April 13, 1749 – September 18, 1811), born at Geneva and died in Le Mas-d'Agenais, was a Genevan mathematician who contributed to the development of differential equations, finite differences, and the calculus of probabilities. He was also active in philosophy, astronomy and psychology.
Biography
Nephew of the naturalist Abraham Trembley, Jean Trembley first studied law in Geneva, before turning to astronomy under the direction of Jacques-André Mallet, director of the Geneva Observatory. He also traveled in the Alps with Horace-Bénédict de Saussure and made with him his doctoral dissertation on the theory of generation (1767). In it, he advocated the views of Charles Bonnet, whose disciple he always pretended to be in the fields of philosophy and psychology.
He made part of his career in Berlin, where he was a member of the Prussian Academy of Science and Letters.
He published 30 articles in the Mémoires de l'Académie de Berlin and a few others in Bode's Jahrbuch and in other periodicals.
He was a correspondent of the Paris Academy of Sciences (1784), later Institute of France (1804), an honorary member of the Imperial Academy of Russia in St. Petersburg (1793), and a member of the Berlin Academy of Prussia (1794; honorary member in 1807).
References
1749 births
1811 deaths
18th-century scientists from the Republic of Geneva
Philosophers from the Republic of Geneva
Mathematicians from the Republic of Geneva
18th-century mathematicians
19th-century mathe
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https://en.wikipedia.org/wiki/McCullagh%27s%20parametrization%20of%20the%20Cauchy%20distributions
|
In probability theory, the "standard" Cauchy distribution is the probability distribution whose probability density function (pdf) is
for x real. This has median 0, and first and third quartiles respectively −1 and +1. Generally, a Cauchy distribution is any probability distribution belonging to the same location-scale family as this one. Thus, if X has a standard Cauchy distribution and μ is any real number and σ > 0, then Y = μ + σX has a Cauchy distribution whose median is μ and whose first and third quartiles are respectively μ − σ and μ + σ.
McCullagh's parametrization, introduced by Peter McCullagh, professor of statistics at the University of Chicago, uses the two parameters of the non-standardised distribution to form a single complex-valued parameter, specifically, the complex number θ = μ + iσ, where i is the imaginary unit. It also extends the usual range of scale parameter to include σ < 0.
Although the parameter is notionally expressed using a complex number, the density is still a density over the real line. In particular the density can be written using the real-valued parameters μ and σ, which can each take positive or negative values, as
where the distribution is regarded as degenerate if σ = 0. An alternative form for the density can be written using the complex parameter θ = μ + iσ as
where .
To the question "Why introduce complex numbers when only real-valued random variables are involved?", McCullagh wrote:
To this question I can give no better
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https://en.wikipedia.org/wiki/Curvature%20invariant
|
In Riemannian geometry and pseudo-Riemannian geometry, curvature invariants are scalar quantities constructed from tensors that represent curvature. These tensors are usually the Riemann tensor, the Weyl tensor, the Ricci tensor and tensors formed from these by the operations of taking dual contractions and covariant differentiations.
Types of curvature invariants
The invariants most often considered are polynomial invariants. These are polynomials constructed from contractions such as traces. Second degree examples are called quadratic invariants, and so forth. Invariants constructed using covariant derivatives up to order n are called n-th order differential invariants.
The Riemann tensor is a multilinear operator of fourth rank acting on tangent vectors. However, it can also be considered a linear operator acting on bivectors, and as such it has a characteristic polynomial, whose coefficients and roots (eigenvalues) are polynomial scalar invariants.
Physical applications
In metric theories of gravitation such as general relativity, curvature scalars play an important role in telling distinct spacetimes apart.
Two of the most basic curvature invariants in general relativity are the Kretschmann scalar
and the Chern–Pontryagin scalar,
These are analogous to two familiar quadratic invariants of the electromagnetic field tensor in classical electromagnetism.
An important unsolved problem in general relativity is to give a basis (and any syzygies) for the zero-th o
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https://en.wikipedia.org/wiki/Cartan%E2%80%93Karlhede%20algorithm
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The Cartan–Karlhede algorithm is a procedure for completely classifying and comparing Riemannian manifolds. Given two Riemannian manifolds of the same dimension, it is not always obvious whether they are locally isometric. Élie Cartan, using his exterior calculus with his method of moving frames, showed that it is always possible to compare the manifolds. Carl Brans developed the method further, and the first practical implementation was presented by in 1980.
The main strategy of the algorithm is to take covariant derivatives of the Riemann tensor. Cartan showed that in n dimensions at most n(n+1)/2 differentiations suffice. If the Riemann tensor and its derivatives of the one manifold are algebraically compatible with the other, then the two manifolds are isometric. The Cartan–Karlhede algorithm therefore acts as a kind of generalization of the Petrov classification.
The potentially large number of derivatives can be computationally prohibitive. The algorithm was implemented in an early symbolic computation engine, SHEEP, but the size of the computations proved too challenging for early computer systems to handle. For most problems considered, far fewer derivatives than the maximum are actually required, and the algorithm is more manageable on modern computers. On the other hand, no publicly available version exists in more modern software.
Physical applications
The Cartan–Karlhede algorithm has important applications in general relativity. One reason for this
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https://en.wikipedia.org/wiki/Carminati%E2%80%93McLenaghan%20invariants
|
In general relativity, the Carminati–McLenaghan invariants or CM scalars are a set of 16 scalar curvature invariants for the Riemann tensor. This set is usually supplemented with at least two additional invariants.
Mathematical definition
The CM invariants consist of 6 real scalars plus 5 complex scalars, making a total of 16 invariants. They are defined in terms of the Weyl tensor and its right (or left) dual , the Ricci tensor , and the trace-free Ricci tensor
In the following, it may be helpful to note that if we regard as a matrix, then is the square of this matrix, so the trace of the square is , and so forth.
The real CM scalars are:
(the trace of the Ricci tensor)
The complex CM scalars are:
The CM scalars have the following degrees:
is linear,
are quadratic,
are cubic,
are quartic,
are quintic.
They can all be expressed directly in terms of the Ricci spinors and Weyl spinors, using Newman–Penrose formalism; see the link below.
Complete sets of invariants
In the case of spherically symmetric spacetimes or planar symmetric spacetimes, it is known that
comprise a complete set of invariants for the Riemann tensor. In the case of vacuum solutions, electrovacuum solutions and perfect fluid solutions, the CM scalars comprise a complete set. Additional invariants may be required for more general spacetimes; determining the exact number (and possible syzygies among the various invariants) is an open problem.
See also
Curvature invariant, for more ab
|
https://en.wikipedia.org/wiki/Parameterized%20post-Newtonian%20formalism
|
In physics, precisely in the study of the theory of general relativity and many alternatives to it, the post-Newtonian formalism is a calculational tool that expresses Einstein's (nonlinear) equations of gravity in terms of the lowest-order deviations from Newton's law of universal gravitation. This allows approximations to Einstein's equations to be made in the case of weak fields. Higher-order terms can be added to increase accuracy, but for strong fields, it may be preferable to solve the complete equations numerically. Some of these post-Newtonian approximations are expansions in a small parameter, which is the ratio of the velocity of the matter forming the gravitational field to the speed of light, which in this case is better called the speed of gravity. In the limit, when the fundamental speed of gravity becomes infinite, the post-Newtonian expansion reduces to Newton's law of gravity.
The parameterized post-Newtonian formalism or PPN formalism, is a version of this formulation that explicitly details the parameters in which a general theory of gravity can differ from Newtonian gravity. It is used as a tool to compare Newtonian and Einsteinian gravity in the limit in which the gravitational field is weak and generated by objects moving slowly compared to the speed of light. In general, PPN formalism can be applied to all metric theories of gravitation in which all bodies satisfy the Einstein equivalence principle (EEP). The speed of light remains constant in PPN for
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https://en.wikipedia.org/wiki/Location%E2%80%93scale%20family
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In probability theory, especially in mathematical statistics, a location–scale family is a family of probability distributions parametrized by a location parameter and a non-negative scale parameter. For any random variable whose probability distribution function belongs to such a family, the distribution function of also belongs to the family (where means "equal in distribution"—that is, "has the same distribution as").
In other words, a class of probability distributions is a location–scale family if for all cumulative distribution functions and any real numbers and , the distribution function is also a member of .
If has a cumulative distribution function , then has a cumulative distribution function .
If is a discrete random variable with probability mass function , then is a discrete random variable with probability mass function .
If is a continuous random variable with probability density function , then is a continuous random variable with probability density function .
Moreover, if and are two random variables whose distribution functions are members of the family, and assuming existence of the first two moments and has zero mean and unit variance,
then can be written as , where and are the mean and standard deviation of .
In decision theory, if all alternative distributions available to a decision-maker are in the same location–scale family, and the first two moments are finite, then a two-moment decision model can apply, and decision-m
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https://en.wikipedia.org/wiki/Hole%20argument
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In general relativity, the hole argument is an apparent paradox that much troubled Albert Einstein while developing his famous field equations.
Some philosophers of physics take the argument to raise a problem for manifold substantialism, a doctrine that the manifold of events in spacetime is a "substance" which exists independently of the metric field defined on it or the matter within it. Other philosophers and physicists disagree with this interpretation, and view the argument as a confusion about gauge invariance and gauge fixing instead.
Einstein's hole argument
In a usual field equation, knowing the source of the field, and the boundary conditions, determines the field everywhere. For example, if we are given the current and charge density and appropriate boundary conditions, Maxwell's equations determine the electric and magnetic fields. They do not determine the vector potential though, because the vector potential depends on an arbitrary choice of gauge.
Einstein noticed that if the equations of gravity are generally covariant, then the metric cannot be determined uniquely by its sources as a function of the coordinates of spacetime. As an example: consider a gravitational source, such as the Sun. Then there is some gravitational field described by a metric g(r). Now perform a coordinate transformation r r' where r' is the same as r for points which are inside the Sun but r' is different from r outside the Sun. The coordinate description of the interior of the Sun
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https://en.wikipedia.org/wiki/Building%20occupancy%20classifications
|
Building occupancy classifications refer to categorizing structures based on their usage and are primarily used for building and fire code enforcement. They are usually defined by model building codes, and vary, somewhat, among them. Often, many of them are subdivided.
Classifications by Group
The following is based on the International Building Code, the most commonly used building code in the United States:
Assembly (Group A) - places used for people gathering for entertainment, worship, and eating or drinking. Examples: churches, restaurants (with 50 or more possible occupants), theaters, and stadiums. Group A is divided into five sub groups:
A-1 Buildings intended for the production and viewing of performing arts or motion pictures (theaters, concert halls).
A-2 Buildings intended for food and/or drink consumption (restaurants).
A-3 Buildings intended for worship, recreation or amusement and other assembly uses not otherwise classified.
A-4 Buildings intended for viewing of indoor sporting events and activities with spectator seating (arenas).
A-5 Buildings intended for participation in or viewing outdoor activities (stadiums).
Business (Group B) - places where services are provided (not to be confused with mercantile, below). Examples: banks, insurance agencies, government buildings (including police and fire stations), and doctor's offices.
Educational (Group E) - schools and day care centers up to the 12th grade.
Factory (Group F) - places where goods are ma
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https://en.wikipedia.org/wiki/The%20Two-Minute%20Miracles
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The Two-Minute Miracles are a Canadian indie rock band from London, Ontario, fronted by songwriter and singer-guitarist Andy Magoffin. The band had a history of fluid membership.
History
The band's name was taken from their early preference for keeping their songs approximately two minutes long, although some songs on their later recordings have exceeded that length. Exclaim! magazine has described the band's songs as "catchy, richly melodic pop tunes occasionally run through with a sinuous, alt-country flavour and an underlying element of playful eccentricity."
The band released three albums on Teenage USA; the second, 13 Songs from the House of Miracles, included horns, banjo, lap steel and piano. The third, The Silence of Animals, was released in 2003. The band later signed with Weewerk. Weewerk released Volume 3.5: Rats, a digital-only preview of the full-length, in July 2007 and Volume IV: The Lions of Love which was released in October 2007. At that time the band consisted of Magoffin, guitarist Justin Nace, keyboardist Michael Christoff, bassist Greg Smith and drummer Aaron Curtis.
Discography
1999: Volume I
2001: Volume II: Thirteen Songs from the House of Miracles
2003: Volume III: The Silence of Animals
2007: Volume 3.5: Rats (Limited EP, digital only)
2007: Volume IV: The Lions of Love
References
External links
Weewerk record label site
The Two-Minute Miracles at CBC Radio 3
Musical groups established in 1995
Musical groups from London, Ontario
Canadi
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https://en.wikipedia.org/wiki/Tungstite
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Tungstite is a hydrous tungsten oxide mineral with formula: WO3·H2O. It is a secondary mineral formed by the weathering of other tungsten containing minerals. It crystallizes in the orthorhombic system in translucent yellow to yellow green masses. It is clay-like with Mohs hardness of 2.5 and a specific gravity of 5.5.
It was first described in 1868 for an occurrence near Trumbull, Connecticut at the Hubbard Tungsten Mine at Long Hill.
References
Mindat with location data
Webmineral
Handbook of mineralogy
Tungsten minerals
Hydroxide minerals
Trumbull, Connecticut
Orthorhombic minerals
Minerals in space group 62
Minerals described in 1868
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https://en.wikipedia.org/wiki/Harris%20City%20Academy%20Crystal%20Palace
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Harris City Academy Crystal Palace is a mixed-sex secondary school in Croydon, south London, England. It was established in 1990 to replace Sylvan High School, a newly built mixed comprehensive school which had opened in 1974. Sylvan, judged to be under-performing, re-opened as a City Technology College (CTC) sponsored by Lord Harris of Peckham. In September 2007, Harris CTC became Harris City Academy Crystal Palace.
Background
The new Harris CTC introduced new systems and structures and results steadily improved. In recent years the examination performance of the school has been excellent.
The conversion to Academy status in September 2007 brought with it the promise of £10 Million for new buildings and facilities. The work on the new buildings was completed by November 2010, with a new sixth form block, reception, internal walkways and classrooms now in use.
The Sixth Form results were also the best ever achieved by the Academy with 100% of students passing their A-level exams and 82% of all grades achieved resulting in a grade A, B or C.
In October 2009, under the new tougher Ofsted inspection criteria, the Academy became the first secondary school in the country to achieve an outstanding grade in each of the 30 categories. By Easter 2010, the Academy was still the only school in England to have achieved this result.
The 2014 Ofsted report rated the academy 'outstanding'.
Over 2000 applications were received for 180 places in Year 7 for September 2009. The intake of
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https://en.wikipedia.org/wiki/List%20of%20airports%20in%20the%20Czech%20Republic
|
This is a list of airports in the Czech Republic, grouped by type and sorted by location.
Passenger statistics
Czech Republic's airports with number of passengers served in 2014 / 2015 years.
Airports
Railway connections
Since 2015, Ostrava Airport has had a railway connection. It is the only airport with a railway connection in the Czech Republic (via line S4), but there are plans to connect Prague Airport to the railway network.
See also
Czech Air Force
Transport in the Czech Republic
List of airlines of the Czech Republic
List of airports by ICAO code: L#LK – Czech Republic
Wikipedia: Airline destination lists: Europe#Czech Republic
References
Sources
Czech Ministry of Transport
– includes IATA codes
– ICAO codes
– IATA and ICAO codes
Czech Republic
Airports
Czech Republic
Airports
|
https://en.wikipedia.org/wiki/Generalized%20inverse%20Gaussian%20distribution
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In probability theory and statistics, the generalized inverse Gaussian distribution (GIG) is a three-parameter family of continuous probability distributions with probability density function
where Kp is a modified Bessel function of the second kind, a > 0, b > 0 and p a real parameter. It is used extensively in geostatistics, statistical linguistics, finance, etc. This distribution was first proposed by Étienne Halphen.
It was rediscovered and popularised by Ole Barndorff-Nielsen, who called it the generalized inverse Gaussian distribution. Its statistical properties are discussed in Bent Jørgensen's lecture notes.
Properties
Alternative parametrization
By setting and , we can alternatively express the GIG distribution as
where is the concentration parameter while is the scaling parameter.
Summation
Barndorff-Nielsen and Halgreen proved that the GIG distribution is infinitely divisible.
Entropy
The entropy of the generalized inverse Gaussian distribution is given as
where is a derivative of the modified Bessel function of the second kind with respect to the order evaluated at
Characteristic Function
The characteristic of a random variable is given as(for a derivation of the characteristic function, see supplementary materials of )
for where denotes the imaginary number.
Related distributions
Special cases
The inverse Gaussian and gamma distributions are special cases of the generalized inverse Gaussian distribution for p = −1/2 and b = 0, r
|
https://en.wikipedia.org/wiki/Atomic%20diffusion
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In chemical physics, atomic diffusion is a diffusion process whereby the random, thermally-activated movement of atoms in a solid results in the net transport of atoms. For example, helium atoms inside a balloon can diffuse through the wall of the balloon and escape, resulting in the balloon slowly deflating. Other air molecules (e.g. oxygen, nitrogen) have lower mobilities and thus diffuse more slowly through the balloon wall. There is a concentration gradient in the balloon wall, because the balloon was initially filled with helium, and thus there is plenty of helium on the inside, but there is relatively little helium on the outside (helium is not a major component of air). The rate of transport is governed by the diffusivity and the concentration gradient.
In crystals
In the crystal solid state, diffusion within the crystal lattice occurs by either interstitial or substitutional mechanisms and is referred to as lattice diffusion. In interstitial lattice diffusion, a diffusant (such as C in an iron alloy), will diffuse in between the lattice structure of another crystalline element. In substitutional lattice diffusion (self-diffusion for example), the atom can only move by substituting place with another atom. Substitutional lattice diffusion is often contingent upon the availability of point vacancies throughout the crystal lattice. Diffusing particles migrate from point vacancy to point vacancy by the rapid, essentially random jumping about
(jump diffusion).
Sinc
|
https://en.wikipedia.org/wiki/Momentum%20diffusion
|
Momentum diffusion most commonly refers to the diffusion, or spread of momentum between particles (atoms or molecules) of matter, often in the fluid state.
This transport of momentum can occur in any direction of the fluid flow. Momentum diffusion can be attributed to either external pressure or shear stress or both.
Diffusion due to pressure
When pressure is applied on an incompressible fluid the velocity of the fluid will change. The fluid accelerates or decelerates depending on the relative direction of pressure with respect to the flow direction. This is because applying pressure on the fluid has caused momentum diffusion in that direction. Understanding the exact nature of diffusion is a key aspect towards understanding momentum diffusion due to pressure.
Momentum diffusion due to shear stresses
A fluid flowing along a flat plate will stick to it at the point of contact and this is known as the no-slip condition. This is an outcome of the adhesive forces between the flat plate and the fluid. The presence of the wall has an effect up to a certain distance
in the fluid (in the direction perpendicular to the wall area and flow ) and this is known as the boundary layer.
Any layer of fluid that is not in contact with the wall will be flowing with a certain velocity and will be sandwiched between two layers of fluid. Now the layer just above it (flowing with a greater velocity) will try to drag it in the direction of flow, whereas the layer just below it (flowing with
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https://en.wikipedia.org/wiki/Photon%20diffusion
|
Photon diffusion is a situation where photons travel through a material without being absorbed, but rather undergoing repeated scattering events which change the direction of their path. The path of any given photon is then effectively a random walk. A large ensemble of such photons can be said to exhibit diffusion in the material, and can be described with a diffusion equation.
Astrophysics
In astrophysics, photon diffusion occurs inside a stellar atmosphere. To describe this phenomenon, one should develop the transfer equation in moments and use the Eddington approximation to radiative transfer (i.e. the diffusion approximation). In 3D the results are two equations for the photon energy flux:
where is the opacity. By substituting the first equation into the second, one obtains the diffusion equation for the photon energy density:
Medical science
In medicine, the diffusion of photons can be used to create images of the body (mainly brain and breast) and has contributed much to the advance of certain fields of research, such as neuroscience. This technique is known as diffuse optical imaging.
See also
Diffuse reflection
Diffusion damping
Global dimming
Medical optical imaging
Optical tomography
Radiative transfer equation and diffusion theory for photon transport in biological tissue
References
Diffusion
Photonics
|
https://en.wikipedia.org/wiki/Reverse%20diffusion
|
Reverse diffusion refers to a situation where the transport of particles (atoms or molecules) in a medium occurs towards regions of higher concentration gradients, opposite to that observed during diffusion. This phenomenon occurs during phase separation and is described by the Cahn–Hilliard equation. Reverse diffusion also refers to when water is forced from a region of lower concentration to high. It can occur in osmosis.
Diffusion
cs:Reverzní osmóza
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https://en.wikipedia.org/wiki/Project%20Lifesaver
|
Project Lifesaver International is a non-profit 501(c)(3) corporation founded in October 1998, by Chief Gene Saunders, in association with, the Chesapeake, Virginia Sheriff's Office. The organization was formed to develop a program for locating missing persons with dementia, epilepsy, Alzheimer's disease, autism, Down syndrome and other disabilities. The program involves attaching a radio transmitter device to the wrist or ankle of persons at-risk of wandering. The battery operated radio transmitter is attached with a wristband and emits an inaudible pulse once per second, in the FCC allocated and licensed 216 MHz frequency range, that can be picked up by a receiver operated by public safety officers. Project Lifesaver utilizes radio frequency tracking technology, which is tested by member agencies before being approved for field use.
As of March 2023, another milestone was reached with over 4,000 rescues in an average time of less than 30 minutes, normally using only two to three public safety responders.
References
External links
Official website
Medical and health organizations based in Florida
501(c)(3) organizations
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https://en.wikipedia.org/wiki/Crystal%20Geyser
|
Crystal Geyser is a cold water, carbon dioxide driven geyser located on the east bank of the Green River approximately downstream from Green River, Utah, United States.
History
The first written record of Crystal Geyser comes from the July 13, 1869 entry for the Powell Geographic Expedition of 1869 as reported in Powell's book, The Exploration of the Colorado River and Its Canyons:
An hour later we run a long rapid and stop at its foot to examine some interesting rocks, deposited by mineral springs that at one time must have existed here, but which are no longer flowing.
Geology
Crystal Geyser is a cold-water geyser located just above the east bank of the Green River, approximately downstream from Green River, Utah. It is at approximately above sea level. The area surrounding the modern geyser is covered in a thick layer of orange travertine. The travertine is composed of couplets of highly porous, micritic laminae alternating with iron oxide-rich laminae. Aragonite is present near the vent and is replaced by magnesium-poor calcite farther away. The bacterium Leptothrix is probably responsible for the Frutexites‐like iron-rich laminae. Pisoids ("pearls") form in pools near the vent.
It is a rare example of a cold-water carbon dioxide driven geyser; geothermal activity does not play a role in the activity of the geyser. The ground water near the geyser has significant quantities of dissolved carbon dioxide, along with substantial underground gas accumulations in the su
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https://en.wikipedia.org/wiki/Fluid%20mechanics
|
Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them.
It has applications in a wide range of disciplines, including mechanical, aerospace, civil, chemical, and biomedical engineering, as well as geophysics, oceanography, meteorology, astrophysics, and biology.
It can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.
It is a branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms; that is, it models matter from a macroscopic viewpoint rather than from microscopic. Fluid mechanics, especially fluid dynamics, is an active field of research, typically mathematically complex. Many problems are partly or wholly unsolved and are best addressed by numerical methods, typically using computers. A modern discipline, called computational fluid dynamics (CFD), is devoted to this approach. Particle image velocimetry, an experimental method for visualizing and analyzing fluid flow, also takes advantage of the highly visual nature of fluid flow.
Brief history
The study of fluid mechanics goes back at least to the days of ancient Greece, when Archimedes investigated fluid statics and buoyancy and formulated his famous law known now as the Archimedes' principle, which was published in his work On Floating Bodies—generally considered to be the first major work on flui
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https://en.wikipedia.org/wiki/Cortical%20magnification
|
Cortical magnification describes how many neurons in an area of the visual cortex are 'responsible' for processing a stimulus of a given size, as a function of visual field location. In the center of the visual field, corresponding to the center of the fovea of the retina, a very large number of neurons process information from a small region of the visual field. If the same stimulus is seen in the periphery of the visual field (i.e. away from the center), it would be processed by a much smaller number of neurons. The reduction of the number of neurons per visual field area from foveal to peripheral representations is achieved in several steps along the visual pathway, starting already in the retina.
For quantitative purposes, the cortical magnification factor is normally expressed in millimeters of cortical surface per degree of visual angle. When expressed in this way, the values of cortical magnification factor vary by a factor of approximately 30 – 90 between the foveal and peripheral representation of the primary visual cortex (V1), depending on how the estimate is obtained.
The inverse of M (i.e. degrees visual angle per millimeter cortical tissue) increases linearly with eccentricity in the visual field.
Visual performance depends importantly on the amount of cortical tissue devoted to the task. As an example, spatial resolution (i.e. visual acuity) is best in the center of the fovea and lowest in the far periphery. Consequently, visual performance variations across
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