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https://en.wikipedia.org/wiki/NOP
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NOP or N.O.P. may refer to:
NOP (code), an assembly language instruction etc. that effectively does nothing at all
3-Nitrooxypropanol, an enzyme inhibitor
"Narodnooslobodilački pokret", also known as the Croatian Partisans
National Opinion Polls, a pollster acquired by GfK
National Organic Program, an American organic food certification program
National Revival of Poland (Narodowe Odrodzenie Polski), a nationalistic Polish political party
Network of practice in social science
New Orleans Pelicans, a National Basketball Association team based in the U.S. city of New Orleans, Louisiana
New Orleans Protocol, a 2004 agreement among white supremacist and neo-Nazi groups
Nike Oregon Project, an athletics team
Nociceptin receptor, a neurotransmitter receptor in the opioid receptor family
Northern Ontario Party, a political party in Ontario, Canada
North Point station, a train station on the Hong Kong MTR Island Line
Sinop Airport (IATA code NOP), an airport in Sinop, in the Black Sea Region of Turkey
See also
Noop (disambiguation)
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https://en.wikipedia.org/wiki/Multilevel%20feedback%20queue
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In computer science, a multilevel feedback queue is a scheduling algorithm. Scheduling algorithms are designed to have some process running at all times to keep the central processing unit (CPU) busy. The multilevel feedback queue extends standard algorithms with the following design requirements:
Separate processes into multiple ready queues based on their need for the processor.
Give preference to processes with short CPU bursts.
Give preference to processes with high I/O bursts. (I/O bound processes will sleep in the wait queue to give other processes CPU time.)
The multilevel feedback queue was first developed by Fernando J. Corbató (1962). For this accomplishment, the Association for Computing Machinery awarded Corbató the Turing Award.
Process scheduling
Whereas the multilevel queue algorithm keeps processes permanently assigned to their initial queue assignments, the multilevel feedback queue shifts processes between queues. The shift is dependent upon the CPU bursts of prior time-slices.
If a process uses too much CPU time, it will be moved to a lower-priority queue.
If a process is I/O-bound or an interactive process, it will be moved to a higher-priority queue.
If a process is waiting too long in a low-priority queue and starving, it will be aged to a higher-priority queue.
Algorithm
Multiple FIFO queues are used and the operation is as follows:
A new process is inserted at the end (tail) of the top-level FIFO queue.
At some stage the process reaches the h
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https://en.wikipedia.org/wiki/Prototype%20Verification%20System
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The Prototype Verification System (PVS) is a specification language integrated with support tools and an automated theorem prover, developed at the Computer Science Laboratory of SRI International in Menlo Park, California.
PVS is based on a kernel consisting of an extension of Church's theory of types with dependent types, and is fundamentally a classical typed higher-order logic. The base types include uninterpreted types that may be introduced by the user, and built-in types such as the booleans, integers, reals, and the ordinals. Type-constructors include functions, sets, tuples, records, enumerations, and abstract data types. Predicate subtypes and dependent types can be used to introduce constraints; these constrained types may incur proof obligations (called type-correctness conditions or TCCs) during typechecking. PVS specifications are organized into parameterized theories.
The system is implemented in Common Lisp, and is released under the GNU General Public License (GPL).
See also
Formal methods
List of proof assistants
References
Owre, Shankar, and Rushby, 1992. PVS: A Prototype Verification System. Published in the CADE 11 conference proceedings.
External links
PVS website at SRI International's Computer Science Laboratory
Summary of PVS by John Rushby at the Mechanized Reasoning database of Michael Kohlhase and Carolyn Talcott
Formal specification languages
Proof assistants
Dependently typed languages
Lisp (programming language)
Common Lisp (progra
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https://en.wikipedia.org/wiki/Syringe%20driver
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A syringe driver, also known as a syringe pump, is a small infusion pump, used to gradually administer small amounts of fluid (with or without medication) to a patient or for use in chemical and biomedical research. Some syringe drivers can both infuse and withdraw solutions.
Uses
Syringe drivers can be used for electrospinning, electrospraying, microdialysis, microfluidics, dispensing/dilution, tissue perfusion, and fluid circulation.
Intravenous therapy
Syringe drivers are useful for delivering intravenous (IV) therapies over several minutes. They infuse solutions at a constant rate. In the case of a medication which should be slowly pushed in over the course of several minutes, this device saves staff time and reduces medical errors. It is useful for patients who cannot take medicines orally (such as those with difficulty swallowing), and for medications too harmful to be taken orally.
Palliative care
Syringe drivers are particularly useful in palliative care, to continuously administer analgesics (painkillers), antiemetics (medication to suppress nausea and vomiting) and other drugs. This prevents periods during which medication levels in the blood are too high or too low, and avoids the use of multiple tablets. As medication is administered subcutaneously, the area of administration is practically limitless, although edema may interfere with the action of some drugs.
Research
Syringe pumps are useful in microfluidic applications, such as microreactor design and t
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https://en.wikipedia.org/wiki/Lactarius
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Lactarius is a genus of mushroom-producing, ectomycorrhizal fungi, containing several edible species. The species of the genus, commonly known as milk-caps, are characterized by the milky fluid ("latex") they exude when cut or damaged. Like the closely related genus Russula, their flesh has a distinctive brittle consistency. It is a large genus with over 500 known species, mainly distributed in the Northern hemisphere. Recently, the genus Lactifluus has been separated from Lactarius based on molecular phylogenetic evidence.
Systematics and taxonomy
The genus Lactarius was described by Christian Hendrik Persoon in 1797 with L. piperatus as the original type species. In 2011, L. torminosus was accepted as the new type of the genus after the splitting-off of Lactifluus as separate genus.
The name "Lactarius" is derived from the Latin lac, "milk".
Placement within Russulaceae
Molecular phylogenetics uncovered that, while macromorphologically well-defined, milk-caps were in fact a paraphyletic genus; as a consequence, the genera Lactifluus was split from Lactarius, and the species L. furcatus was moved to the new genus Multifurca, together with some former Russula species. Multifurca also represents the likely sister group of Lactarius (see phylogeny, right). In the course of these taxonomical rearrangements, the name Lactarius was conserved for the genus with the new type species Lactarius torminosus; this way, the name Lactarius could be retained for the bigger genus with ma
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https://en.wikipedia.org/wiki/Zitterbewegung
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In physics, the zitterbewegung (, ) is the theoretical prediction of a rapid oscillatory motion of elementary particles that obey relativistic wave equations. This prediction was first discussed by Gregory Breit in 1928 and later by Erwin Schrödinger in 1930 as a result of analysis of the wave packet solutions of the Dirac equation for relativistic electrons in free space, in which an interference between positive and negative energy states produces an apparent fluctuation (up to the speed of light) of the position of an electron around the median, with an angular frequency of , or approximately radians per second.
This apparent oscillatory motion is often interpreted as an artifact of using the Dirac equation in a single particle description and disappears when using quantum field theory. For the hydrogen atom, the zitterbewegung is related to the Darwin term, a small correction of the energy level of the s-orbitals.
Theory
Free spin-1/2 fermion
The time-dependent Dirac equation is written as
,
where is the reduced Planck constant, is the wave function (bispinor) of a fermionic particle spin-½, and is the Dirac Hamiltonian of a free particle:
,
where is the mass of the particle, is the speed of light, is the momentum operator, and and are matrices related to the Gamma matrices , as and .
In the Heisenberg picture, the time dependence of an arbitrary observable obeys the equation
In particular, the time-dependence of the position operator is given by
.
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https://en.wikipedia.org/wiki/Essexite
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Essexite (), also called nepheline monzogabbro (), is a dark gray or black holocrystalline plutonic igneous rock. Its name is derived from the type locality in Essex County, Massachusetts, in the United States.
Modern petrology identifies rocks according to mineralogical criteria. Utilising the IUGS QAPF diagram of Streckeisen (1974) "essexite" is more formally known as nepheline monzodiorite or nepheline monzogabbro depending on the ratio of orthoclase to plagioclase and the abundance of nepheline.
Petrology
In order to produce a magma composition suitable for forming essexite the partial melting of the source rocks must be restricted, generally to less than 10% partial melting. This favors producing a melt rich in large-ion lithophile elements (LILE) such as K, Ba, Rb, Cs, Sr.
The source melts of essexites contain more aluminium and alkali ions than available silica tetrahedra, which is why essexites crystallise nepheline instead of plagioclase. Higher than normal potassium favors the production of orthoclase, which is usually absent from most mafic igneous rocks.
Mineralogy
Essexite can be considered as an alkali gabbro or monzodiorite primarily composed of nepheline, plagioclase, with lesser amounts of alkali feldspar, with mafic minerals composed of any of the following; titanium augite (pyroxene), hornblende and biotite.
Trace mineralogy may include magnetite, ilmenite and accessory olivine (<5%).
Essexite grades into a nepheline monzogabbro with a decrease
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https://en.wikipedia.org/wiki/Ecological%20stability
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In ecology, an ecosystem is said to possess ecological stability (or equilibrium) if it is capable of returning to its equilibrium state after a perturbation (a capacity known as resilience) or does not experience unexpected large changes in its characteristics across time. Although the terms community stability and ecological stability are sometimes used interchangeably, community stability refers only to the characteristics of communities. It is possible for an ecosystem or a community to be stable in some of their properties and unstable in others. For example, a vegetation community in response to a drought might conserve biomass but lose biodiversity.
Stable ecological systems abound in nature, and the scientific literature has documented them to a great extent. Scientific studies mainly describe grassland plant communities and microbial communities. Nevertheless, it is important to mention that not every community or ecosystem in nature is stable (for example, wolves and moose on Isle Royale). Also, noise plays an important role on biological systems and, in some scenarios, it can fully determine their temporal dynamics.
The concept of ecological stability emerged in the first half of the 20th century. With the advancement of theoretical ecology in the 1970s, the usage of the term has expanded to a wide variety of scenarios. This overuse of the term has led to controversy over its definition and implementation.
In 1997, Grimm and Wissel made an inventory of 167 defi
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https://en.wikipedia.org/wiki/Picard%20group
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In mathematics, the Picard group of a ringed space X, denoted by Pic(X), is the group of isomorphism classes of invertible sheaves (or line bundles) on X, with the group operation being tensor product. This construction is a global version of the construction of the divisor class group, or ideal class group, and is much used in algebraic geometry and the theory of complex manifolds.
Alternatively, the Picard group can be defined as the sheaf cohomology group
For integral schemes the Picard group is isomorphic to the class group of Cartier divisors. For complex manifolds the exponential sheaf sequence gives basic information on the Picard group.
The name is in honour of Émile Picard's theories, in particular of divisors on algebraic surfaces.
Examples
The Picard group of the spectrum of a Dedekind domain is its ideal class group.
The invertible sheaves on projective space Pn(k) for k a field, are the twisting sheaves so the Picard group of Pn(k) is isomorphic to Z.
The Picard group of the affine line with two origins over k is isomorphic to Z.
The Picard group of the -dimensional complex affine space: , indeed the exponential sequence yields the following long exact sequence in cohomology
and since we have because is contractible, then and we can apply the Dolbeault isomorphism to calculate by the Dolbeault-Grothendieck lemma.
Picard scheme
The construction of a scheme structure on (representable functor version of) the Picard group, the Picard scheme, is an impo
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https://en.wikipedia.org/wiki/Fermat%27s%20theorem%20on%20sums%20of%20two%20squares
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In additive number theory, Fermat's theorem on sums of two squares states that an odd prime p can be expressed as:
with x and y integers, if and only if
The prime numbers for which this is true are called Pythagorean primes.
For example, the primes 5, 13, 17, 29, 37 and 41 are all congruent to 1 modulo 4, and they can be expressed as sums of two squares in the following ways:
On the other hand, the primes 3, 7, 11, 19, 23 and 31 are all congruent to 3 modulo 4, and none of them can be expressed as the sum of two squares. This is the easier part of the theorem, and follows immediately from the observation that all squares are congruent to 0 or 1 modulo 4.
Since the Diophantus identity implies that the product of two integers each of which can be written as the sum of two squares is itself expressible as the sum of two squares, by applying Fermat's theorem to the prime factorization of any positive integer n, we see that if all the prime factors of n congruent to 3 modulo 4 occur to an even exponent, then n is expressible as a sum of two squares. The converse also holds. This generalization of Fermat's theorem is known as the sum of two squares theorem.
History
Albert Girard was the first to make the observation, characterizing the positive integers (not necessarily primes) that are expressible as the sum of two squares of positive integers; this was published in 1625. The statement that every prime p of the form 4n+1 is the sum of two squares is sometimes called Girard'
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https://en.wikipedia.org/wiki/Freedman%E2%80%93Diaconis%20rule
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In statistics, the Freedman–Diaconis rule can be used to select the width of the bins to be used in a histogram. It is named after David A. Freedman and Persi Diaconis.
For a set of empirical measurements sampled from some probability distribution, the Freedman-Diaconis rule is designed roughly to minimize the integral of the squared difference between the histogram (i.e., relative frequency density) and the density of the theoretical probability distribution.
The general equation for the rule is:
where is the interquartile range of the data and is the number of observations in the sample
Other approaches
With the factor 2 replaced by approximately 2.59, the Freedman-Diaconis rule asymptotically matches Scott's normal reference rule for data sampled
from a normal distribution.
Another approach is to use Sturges' rule: use a bin so large that there are about non-empty bins (Scott, 2009). This works well for n under 200, but was found to be inaccurate for large n.
For a discussion and an alternative approach, see Birgé and Rozenholc.
References
Rules of thumb
Statistical charts and diagrams
Infographics
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https://en.wikipedia.org/wiki/HITS%20algorithm
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Hyperlink-Induced Topic Search (HITS; also known as hubs and authorities) is a link analysis algorithm that rates Web pages, developed by Jon Kleinberg. The idea behind Hubs and Authorities stemmed from a particular insight into the creation of web pages when the Internet was originally forming; that is, certain web pages, known as hubs, served as large directories that were not actually authoritative in the information that they held, but were used as compilations of a broad catalog of information that led users direct to other authoritative pages. In other words, a good hub represents a page that pointed to many other pages, while a good authority represents a page that is linked by many different hubs.
The scheme therefore assigns two scores for each page: its authority, which estimates the value of the content of the page, and its hub value, which estimates the value of its links to other pages.
History
In journals
Many methods have been used to rank the importance of scientific journals. One such method is Garfield's impact factor. Journals such as Science and Nature are filled with numerous citations, making these magazines have very high impact factors. Thus, when comparing two more obscure journals which have received roughly the same number of citations but one of these journals has received many citations from Science and Nature, this journal needs be ranked higher. In other words, it is better to receive citations from an important journal than from an unimporta
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https://en.wikipedia.org/wiki/Eurodif
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Eurodif, which means European Gaseous Diffusion Uranium Enrichment Consortium, is a subsidiary of the French company Orano, which operates a uranium enrichment plant established at the Tricastin Nuclear Power Center in Pierrelatte in Drôme. The nuclear site of Pierrelatte includes many nuclear installations, of which the largest are the Eurodif fuel factory and the Tricastin nuclear power station.
Enriched uranium is the preferred fuel for light water reactors, a common nuclear power technology.
History
In 1973 France, Belgium, Italy, Spain and Sweden formed the joint stock company EURODIF. Sweden withdrew from the project in 1974. In 1975 Sweden's 10 per cent share in EURODIF was transferred to Iran as a result of an arrangement between France and Iran. The French government subsidiary company Cogema and the Iranian Government established the Sofidif () enterprise with 60 per cent and 40 per cent shares, respectively. In turn, Sofidif acquired a 25 per cent share in EURODIF, through which Iran attained its 10 per cent share of EURODIF.
In 1974, the Mohammad Reza Shah Pahlavi, Shah of Iran, lent $1 billion (and another $180 million in 1977) for the construction of the factory, in order to have the right to buy 10% of the production. Iran remains a shareholder of Eurodif via Sofidif. The Franco-Iranian consortium shareholder still owns 25% of Eurodif.
The Georges-Besse plant, named after Georges Besse, its founder, provides uranium to forty producers of nuclear electricit
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https://en.wikipedia.org/wiki/Film%20adaptation
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A film adaptation is the transfer of a work or story, in whole or in part, to a feature film. Although often considered a type of derivative work, film adaptation has been conceptualized recently by academic scholars such as Robert Stam as a dialogic process.
While the most common form of film adaptation is the use of a novel as the basis, other works adapted into films include non-fiction (including journalism), autobiographical works, comic books, scriptures, plays, historical sources and even other films. Adaptation from such diverse resources has been a ubiquitous practice of filmmaking since the earliest days of cinema in nineteenth-century Europe. In contrast to when making a remake, movie directors usually take more creative liberties when creating a film adaptation.
Elision and interpolation
In 1924, Erich von Stroheim attempted a literal adaptation of Frank Norris's novel McTeague with his film Greed. The resulting film was 9½ hours long, and was cut to four hours at studio insistence. It was then cut again (without Stroheim's input) to around two hours. The result was a film that was largely incoherent. Since that time, few directors have attempted to put everything in a novel into a film. Therefore, elision is all but essential.
In some cases, film adaptations also interpolate scenes or invent characters. This is especially true when a novel is part of a literary saga. Incidents or quotations from later or earlier novels will be inserted into a single film. Add
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https://en.wikipedia.org/wiki/Nicol%C3%A1s%20Cabrera
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Nicolás Cabrera (1913–1989), was a Spanish physicist who did important work on the theories of crystal growth (specifically the Burton–Cabrera–Frank theory) and the oxidisation of metals. He was the son of another famous Spanish physicist Blas Cabrera and the father of American Physicist Blas Cabrera Navarro. He spent many years in exile during the Francoist State. He was Professor of the Department of physics in the University of Virginia, where he worked from 1952. He became known for his interests in engineering and material science. He founded the physics department and was a professor at the Autonomous University of Madrid (UAM), from 1971. He is considered to have given an impulse to the study of physics in Spain from the time of his return. For a time Javier Solana, whom he met at the University of Virginia, was his assistant in Madrid. Solana has described him as being a brilliant man but badly organized. The Nicolás Cabrera Institute, founded in 1989 in the UAM, is named after him.
External links
1913 births
1989 deaths
Spanish physicists
Fellows of the American Physical Society
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https://en.wikipedia.org/wiki/Reynolds%20stress
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In fluid dynamics, the Reynolds stress is the component of the total stress tensor in a fluid obtained from the averaging operation over the Navier–Stokes equations to account for turbulent fluctuations in fluid momentum.
Definition
The velocity field of a flow can be split into a mean part and a fluctuating part using Reynolds decomposition. We write
with being the flow velocity vector having components in the coordinate direction (with denoting the components of the coordinate vector ). The mean velocities are determined by either time averaging, spatial averaging or ensemble averaging, depending on the flow under study. Further denotes the fluctuating (turbulence) part of the velocity.
We consider a homogeneous fluid, whose density ρ is taken to be a constant. For such a fluid, the components τ'''ij of the Reynolds stress tensor are defined as:
Another – often used – definition, for constant density, of the Reynolds stress components is:
which has the dimensions of velocity squared, instead of stress.
Averaging and the Reynolds stress
To illustrate, Cartesian vector index notation is used. For simplicity, consider an incompressible fluid:
Given the fluid velocity as a function of position and time, write the average fluid velocity as , and the velocity fluctuation is . Then .
The conventional ensemble rules of averaging are that
One splits the Euler equations (fluid dynamics) or the Navier-Stokes equations into an average and a fluctuating part. One finds
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https://en.wikipedia.org/wiki/Marangoni%20effect
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The Marangoni effect (also called the Gibbs–Marangoni effect) is the mass transfer along an interface between two phases due to a gradient of the surface tension. In the case of temperature dependence, this phenomenon may be called thermo-capillary convection (or Bénard–Marangoni convection).
History
This phenomenon was first identified in the so-called "tears of wine" by physicist James Thomson (Lord Kelvin's brother) in 1855. The general effect is named after Italian physicist Carlo Marangoni, who studied it for his doctoral dissertation at the University of Pavia and published his results in 1865. A complete theoretical treatment of the subject was given by J. Willard Gibbs in his work On the Equilibrium of Heterogeneous Substances (1875-8).
Mechanism
Since a liquid with a high surface tension pulls more strongly on the surrounding liquid than one with a low surface tension, the presence of a gradient in surface tension will naturally cause the liquid to flow away from regions of low surface tension. The surface tension gradient can be caused by concentration gradient or by a temperature gradient (surface tension is a function of temperature).
In simple cases, the speed of the flow , where is the difference in surface tension and is the viscosity of the liquid. Water has a surface tension of around 0.07 N/m, and a viscosity of approximately 10−3 Pa s, at room temperature. So even variations of a few percent in the surface tension of water can generate Marangoni flows
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https://en.wikipedia.org/wiki/Candy%20/%20Molly%27s%20Lips
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"Candy"/"Molly's Lips" is a vinyl-only split-single from the American rock bands the Fluid and Nirvana. It was released in January 1991 on Sub Pop records and includes two live tracks: "Candy" by the Fluid; and "Molly's Lips", a cover of a song by the Vaselines, performed by Nirvana.
Background
"Candy" first appeared on the Fluid's 1990 EP, Glue. The EP was re-released on CD in 1993 along with their 1989 album, Roadmouth.
"Molly's Lips" was recorded live on February 9, 1990, at the Pine Street Theatre in Portland, Oregon. It was written by Scottish band the Vaselines about Molly Weir, according to band member Eugene Kelly, presumably because her Rentaghost television character Hazel McWitch typically appeared in whiteface with emphatic red lips. According to Michael Azerrad's 1993 Nirvana biography Come as You Are: The Story of Nirvana, the band's frontman Kurt Cobain was opposed to the release of the track, feeling that this version was not strong. However, the single constituted part of the band's buyout deal from their former record label Sub Pop; "Candy/Molly's Lips" was Nirvana's final release there. The word "Later" is etched into the single's run-out groove. A remix of this version of "Molly's Lips" was included on the 2009 reissue of the Nirvana debut album Bleach.
Nirvana also recorded a studio version of "Molly's Lips" on BBC Radio 1 for John Peel in October 1990 during drummer Dave Grohl's first recording session with the band. It appeared on the 1992 tour EP Ho
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https://en.wikipedia.org/wiki/Winner-take-all%20%28computing%29
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Winner-take-all is a computational principle applied in computational models of neural networks by which neurons compete with each other for activation. In the classical form, only the neuron with the highest activation stays active while all other neurons shut down; however, other variations allow more than one neuron to be active, for example the soft winner take-all, by which a power function is applied to the neurons.
Neural networks
In the theory of artificial neural networks, winner-take-all networks are a case of competitive learning in recurrent neural networks. Output nodes in the network mutually inhibit each other, while simultaneously activating themselves through reflexive connections. After some time, only one node in the output layer will be active, namely the one corresponding to the strongest input. Thus the network uses nonlinear inhibition to pick out the largest of a set of inputs. Winner-take-all is a general computational primitive that can be implemented using different types of neural network models, including both continuous-time and spiking networks.
Winner-take-all networks are commonly used in computational models of the brain, particularly for distributed decision-making or action selection in the cortex. Important examples include hierarchical models of vision, and models of selective attention and recognition. They are also common in artificial neural networks and neuromorphic analog VLSI circuits. It has been formally proven that the winner-t
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https://en.wikipedia.org/wiki/Hydraulic%20conductivity
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In science and engineering, hydraulic conductivity (, in SI units of meters per second), is a property of porous materials, soils and rocks,< that describes the ease with which a fluid (usually water) can move through the pore space, or fractures network. It depends on the intrinsic permeability (, unit: m) of the material, the degree of saturation, and on the density and viscosity of the fluid. Saturated hydraulic conductivity, , describes water movement through saturated media.
By definition, hydraulic conductivity is the ratio of volume flux to hydraulic gradient yielding a quantitative measure of a saturated soil's ability to transmit water when subjected to a hydraulic gradient.
Methods of determination
There are two broad categories of determining hydraulic conductivity:
Empirical approach by which the hydraulic conductivity is correlated to soil properties like pore size and particle size (grain size) distributions, and soil texture
Experimental approach by which the hydraulic conductivity is determined from hydraulic experiments using Darcy's law
The experimental approach is broadly classified into:
Laboratory tests using soil samples subjected to hydraulic experiments
Field tests (on site, in situ) that are differentiated into:
small scale field tests, using observations of the water level in cavities in the soil
large scale field tests, like pump tests in wells or by observing the functioning of existing horizontal drainage systems.
The small scale field tests
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https://en.wikipedia.org/wiki/GLIMMER
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In bioinformatics, GLIMMER (Gene Locator and Interpolated Markov ModelER) is used to find genes in prokaryotic DNA. "It is effective at finding genes in bacteria, archea, viruses, typically finding 98-99% of all relatively long protein coding genes". GLIMMER was the first system that used the interpolated Markov model to identify coding regions. The GLIMMER software is open source and is maintained by Steven Salzberg, Art Delcher, and their colleagues at the Center for Computational Biology at Johns Hopkins University. The original GLIMMER algorithms and software were designed by Art Delcher, Simon Kasif and Steven Salzberg and applied to bacterial genome annotation in collaboration with Owen White.
Versions
GLIMMER 1.0
First Version of GLIMMER "i.e., GLIMMER 1.0" was released in 1998 and it was published in the paper Microbial gene identification using interpolated Markov model. Markov models were used to identify microbial genes in GLIMMER 1.0. GLIMMER considers the local composition sequence dependencies which makes GLIMMER more flexible and more powerful when compared to fixed-order Markov model.
There was a comparison made between interpolated Markov model used by GLIMMER and fifth order Markov model in the paper Microbial gene identification using interpolated Markov models. "GLIMMER algorithm found 1680 genes out of 1717 annotated genes in Haemophilus influenzae where fifth order Markov model found 1574 genes. GLIMMER found 209 additional genes which were not includ
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https://en.wikipedia.org/wiki/Challacolloite
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Challacolloite, KPb2Cl5, is a rare halide mineral. It crystallizes in the monoclinic system (with space group P21/c) and occurs as white fumarolic encrustations on lava. It occurs as intergrowths with cotunnite.
It was first described from a finding at the Challacollo Mine, Iquique, Chile and thereafter identified in specimens from the 1855 Mount Vesuvius eruption and from the Kudryavyi volcano in the Kuriles and also from the Satsuma-Iwojima volcano in Japan. It was recognized as a valid mineral species by the IMA (International Mineralogical Association) in 2005.
Artificially grown KPb2Cl5 crystals are used for lasers.
External links
Potassium minerals
Lead minerals
Halide minerals
Monoclinic minerals
Minerals in space group 14
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https://en.wikipedia.org/wiki/Ecosystem%20service
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Ecosystem services are the many and varied benefits to humans provided by the natural environment and healthy ecosystems. Such ecosystems include, for example, agroecosystems, forest ecosystem, grassland ecosystems, and aquatic ecosystems. These ecosystems, functioning in healthy relationships, offer such things as natural pollination of crops, clean air, extreme weather mitigation, and human mental and physical well-being. Collectively, these benefits are becoming known as ecosystem services, and are often integral to the provision of food, the provisioning of clean drinking water, the decomposition of wastes, and the resilience and productivity of food ecosystems.
While scientists and environmentalists have discussed ecosystem services implicitly for decades, the Millennium Ecosystem Assessment (MA) in the early 2000s popularized this concept. There, ecosystem services are grouped into four broad categories: provisioning, such as the production of food and water; regulating, such as the control of climate and disease; supporting, such as nutrient cycles and oxygen production; and cultural, such as spiritual and recreational benefits. To help inform decision-makers, many ecosystem services are being evaluated to draw equivalent comparisons to human-engineered infrastructure and services.
Estuarine and coastal ecosystems are marine ecosystems that perform the four categories of ecosystem services in a variety of ways. For example, their regulating services include climate r
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https://en.wikipedia.org/wiki/Acousto-optic%20modulator
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An acousto-optic modulator (AOM), also called a Bragg cell or an acousto-optic deflector (AOD), uses the acousto-optic effect to diffract and shift the frequency of light using sound waves (usually at radio-frequency). They are used in lasers for Q-switching, telecommunications for signal modulation, and in spectroscopy for frequency control. A piezoelectric transducer is attached to a material such as glass. An oscillating electric signal drives the transducer to vibrate, which creates sound waves in the material. These can be thought of as moving periodic planes of expansion and compression that change the index of refraction. Incoming light scatters (see Brillouin scattering) off the resulting periodic index modulation and interference occurs similar to Bragg diffraction. The interaction can be thought of as a three-wave mixing process resulting in Sum-frequency generation or Difference-frequency generation between phonons and photons.
Principles of operation
A typical AOM operates under Bragg Condition, where the incident light comes at Bragg angle from the perpendicular of the sound wave's propagation.
Diffraction
When the incident light beam is at Bragg angle, a diffraction pattern emerges where an order of diffracted beam occurs at each angle θ that satisfies:
Here, is the order of diffraction, is the wavelength of light in vacuum, and is the wavelength of the sound. Note that m = 0 order travels in the same direction as the incident beam.
Diffraction fro
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https://en.wikipedia.org/wiki/Under%20Suspicion%20%282000%20film%29
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Under Suspicion is a 2000 American-French thriller film directed by Stephen Hopkins and starring Gene Hackman, Morgan Freeman, Monica Bellucci and Thomas Jane. The film is based on the 1981 French film Garde à vue and the British novel Brainwash (1979), written by John Wainwright. It was screened out of competition at the 2000 Cannes Film Festival.
Plot
Wealthy tax attorney Henry Hearst (Hackman) is about to give a speech at an exclusive fundraising party in San Juan, Puerto Rico, as the city celebrates the San Sebastián Festival. He is called to the police station to be questioned about the body he found the day before – that of a young girl who had been raped and murdered. Hearst changes his version of events several times; Captain Victor Benezet (Freeman) and Detective Felix Owens (Jane) question him about inconsistencies in his story. Hearst quickly realizes that they think he committed the murder, as well as that of another young girl whose body was found days earlier, but at this stage of questioning he is unalarmed. Benezet is under pressure from his boss (Miguel Ángel Suárez) to free Hearst so that he can give his speech. As there is no conclusive proof, Benezet's superior at the party says to let Hearst at least come to the party and give his fund raising speech. After a fracas at the police station, Hearst arrives, disheveled, at the party, gives his speech, and is then escorted back to the police station.
At the party, a crowd is gossiping and Chantal (Bellucci),
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https://en.wikipedia.org/wiki/Rademacher%20distribution
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In probability theory and statistics, the Rademacher distribution (which is named after Hans Rademacher) is a discrete probability distribution where a random variate X has a 50% chance of being +1 and a 50% chance of being -1.
A series (that is, a sum) of Rademacher distributed variables can be regarded as a simple symmetrical random walk where the step size is 1.
Mathematical formulation
The probability mass function of this distribution is
In terms of the Dirac delta function, as
Bounds on sums of independent Rademacher variables
There are various results in probability theory around analyzing the sum of i.i.d. Rademacher variables, including concentration inequalities such as Bernstein inequalities as well as anti-concentration inequalities like Tomaszewski's conjecture.
Concentration inequalities
Let {xi} be a set of random variables with a Rademacher distribution. Let {ai} be a sequence of real numbers. Then
where ||a||2 is the Euclidean norm of the sequence {ai}, t > 0 is a real number and Pr(Z) is the probability of event Z.
Let Y = Σ xiai and let Y be an almost surely convergent series in a Banach space. The for t > 0 and s ≥ 1 we have
for some constant c.
Let p be a positive real number. Then the Khintchine inequality says that
where c1 and c2 are constants dependent only on p.
For p ≥ 1,
Tomaszewski’s conjecture
In 1986, Bogusław Tomaszewski proposed a question about the distribution of the sum of independent Rademacher variables. A series
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https://en.wikipedia.org/wiki/Polly%20and%20Molly
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Polly and Molly (born 1997), two ewes, were the first mammals to have been successfully cloned from an adult somatic cell and to be transgenic animals at the same time. This is not to be confused with Dolly the Sheep, the first animal to be successfully cloned from an adult somatic cell where there wasn’t modification carried out on the adult donor nucleus. Polly and Molly, like Dolly the Sheep, were cloned at the Roslin Institute in Edinburgh, Scotland.
The creation of Polly and Molly built on the somatic nuclear transfer experiments that led to the cloning of Dolly the Sheep. The crucial difference was that in creating Polly and Molly, scientists used cells into which a new gene had been inserted. The gene chosen was a therapeutic protein to demonstrate the potential of such recombinant DNA technology combined with animal cloning. This could hopefully be used to produce pharmacological and therapeutic proteins to treat human diseases. The protein in question was the human blood clotting factor IX. Another difference from Dolly the Sheep was the source cell type of the nucleus that was transferred. Although Polly and Molly were nuclear clones, they had different mtDNA that was different from the nuclear cells where they received their DNA.
Prior to the production of Polly and Molly, the only demonstrated way to make a transgenic animal was by microinjection of DNA into the pronuclei of fertilized oocytes (eggs). However, only a small proportion of the animals will integrat
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https://en.wikipedia.org/wiki/Daniell%20cell
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The Daniell cell is a type of electrochemical cell invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consists of a copper pot filled with a copper (II) sulfate solution, in which is immersed an unglazed earthenware container filled with sulfuric acid and a zinc electrode. He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first. Zinc sulfate may be substituted for the sulfuric acid. The Daniell cell was a great improvement over the existing technology used in the early days of battery development. A later variant of the Daniell cell called the gravity cell or crowfoot cell was invented in the 1860s by a Frenchman named Callaud and became a popular choice for electrical telegraphy.
The Daniell cell is also the historical basis for the contemporary definition of the volt, which is the unit of electromotive force in the International System of Units. The definitions of electrical units that were proposed at the 1881 International Conference of Electricians were designed so that the electromotive force of the Daniell cell would be about 1.0 volts. With contemporary definitions, the standard potential of the Daniell cell at 25 °C is actually 1.10 V.
Chemistry
In the Daniell cell, copper and zinc electrodes are immersed in a solution of copper(II) sulfate and zinc sulfate, respectively.
At the anode (negative el
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https://en.wikipedia.org/wiki/Vascular%20endothelial%20growth%20factor
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Vascular endothelial growth factor (VEGF, ), originally known as vascular permeability factor (VPF), is a signal protein produced by many cells that stimulates the formation of blood vessels. To be specific, VEGF is a sub-family of growth factors, the platelet-derived growth factor family of cystine-knot growth factors. They are important signaling proteins involved in both vasculogenesis (the de novo formation of the embryonic circulatory system) and angiogenesis (the growth of blood vessels from pre-existing vasculature).
It is part of the system that restores the oxygen supply to tissues when blood circulation is inadequate such as in hypoxic conditions. Serum concentration of VEGF is high in bronchial asthma and diabetes mellitus.
VEGF's normal function is to create new blood vessels during embryonic development, new blood vessels after injury, muscle following exercise, and new vessels (collateral circulation) to bypass blocked vessels.
It can contribute to disease. Solid cancers cannot grow beyond a limited size without an adequate blood supply; cancers that can express VEGF are able to grow and metastasize. Overexpression of VEGF can cause vascular disease in the retina of the eye and other parts of the body. Drugs such as aflibercept, bevacizumab, ranibizumab, and pegaptanib can inhibit VEGF and control or slow those diseases.
History
In 1970, Judah Folkman et al. described a factor secreted by tumors causing angiogenesis and called it tumor angiogenesis factor. In
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https://en.wikipedia.org/wiki/Bui%20Tuong%20Phong
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Bui Tuong Phong (December 14, 1942 – July 1975) was a Vietnamese-born computer graphics researcher and pioneer. He invented the widely used Phong shading algorithm and Phong reflection model.
Life
Phong was born in Hanoi, then French Indochina. After attending the Lycée Albert Sarraut there, he moved with his family to Saigon in 1954, where he attended the Lycée Jean Jacques Rousseau. He went to France in 1964 and was admitted to the Grenoble Institute of Technology. He received his from Grenoble in 1966 and his Diplôme d'Ingénieur from the ENSEEIHT, Toulouse, in 1968. In 1968, he joined the (then IRIA) as a researcher in Computer Science, working in the development of operating systems for digital computers.
He went to the University of Utah College of Engineering in September 1971 as a research assistant in Computer Science and he received his Ph.D. from the University of Utah in 1973.
Phong knew that he was terminally ill with leukemia while he was a student. In 1975, after his tenure at the University of Utah, Phong joined Stanford University as a professor.
Phong was married to Bùi Thị Ngọc Bích from Nha Trang, Vietnam, in 1969 in Paris, France. He and his wife had one daughter.
According to Professor Ivan Sutherland and Phong's friends, Phong was intelligent, affable and modest. About improving the quality of synthesized images he wrote, "We do not expect to be able to display the object exactly as it would appear in reality, with texture, overcast shadows, etc.
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https://en.wikipedia.org/wiki/Spiroplasma
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Spiroplasma is a genus of Mollicutes, a group of small bacteria without cell walls. Spiroplasma shares the simple metabolism, parasitic lifestyle, fried-egg colony morphology and small genome of other Mollicutes, but has a distinctive helical morphology, unlike Mycoplasma. It has a spiral shape and moves in a corkscrew motion. Many Spiroplasma are found either in the gut or haemolymph of insects where they can act to manipulate host reproduction, or defend the host as endosymbionts. Spiroplasma are also disease-causing agents in the phloem of plants. Spiroplasmas are fastidious organisms, which require a rich culture medium. Typically they grow well at 30 °C, but not at 37 °C. A few species, notably Spiroplasma mirum, grow well at 37 °C (human body temperature), and cause cataracts and neurological damage in suckling mice. The best studied species of spiroplasmas are Spiroplasma poulsonii, a reproductive manipulator and defensive insect symbiont, Spiroplasma citri, the causative agent of citrus stubborn disease, and Spiroplasma kunkelii, the causative agent of corn stunt disease.
Human pathogenicity
There is some disputed evidence for the role of spiroplasmas in the etiology of transmissible spongiform encephalopathies (TSEs), due primarily to the work of Frank Bastian, summarized below. Other researchers have failed to replicate this work, while the prion model for TSEs has gained very wide acceptance. A 2006 study appears to refute the role of spiroplasmas in the best
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https://en.wikipedia.org/wiki/Phragmoplast
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The phragmoplast is a plant cell specific structure that forms during late cytokinesis. It serves as a scaffold for cell plate assembly and subsequent formation of a new cell wall separating the two daughter cells. The phragmoplast can only be observed in Phragmoplastophyta, a clade that includes the Coleochaetophyceae, Zygnematophyceae, Mesotaeniaceae, and Embryophyta (land plants). Some algae use another type of microtubule array, a phycoplast, during cytokinesis.
Structure
The phragmoplast is a complex assembly of microtubules (MTs), microfilaments (MFs), and endoplasmic reticulum (ER) elements, that assemble in two opposing sets perpendicular to the plane of the future cell plate during anaphase and telophase. It is initially barrel-shaped and forms from the mitotic spindle between the two daughter nuclei while nuclear envelopes reassemble around them. The cell plate initially forms as a disc between the two halves of the phragmoplast structure. While new cell plate material is added to the edges of the growing plate, the phragmoplast microtubules disappear in the center and regenerate at the edges of the growing cell plate. The two structures grow outwards until they reach the outer wall of the dividing cell. If a phragmosome was present in the cell, the phragmoplast and cell plate will grow through the space occupied by the phragmosome. They will reach the parent cell wall exactly at the position formerly occupied by the preprophase band.
The microtubules and actin f
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https://en.wikipedia.org/wiki/Feedback%20arc%20set
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In graph theory and graph algorithms, a feedback arc set or feedback edge set in a directed graph is a subset of the edges of the graph that contains at least one edge out of every cycle in the graph. Removing these edges from the graph breaks all of the cycles, producing a directed acyclic graph, an acyclic subgraph of the given graph. The feedback arc set with the fewest possible edges is the minimum feedback arc set and its removal leaves the maximum acyclic subgraph; weighted versions of these optimization problems are also used. If a feedback arc set is minimal, meaning that removing any edge from it produces a subset that is not a feedback arc set, then it has an additional property: reversing all of its edges, rather than removing them, produces a directed acyclic graph.
Feedback arc sets have applications in circuit analysis, chemical engineering, deadlock resolution, ranked voting, ranking competitors in sporting events, mathematical psychology, ethology, and graph drawing. Finding minimum feedback arc sets and maximum acyclic subgraphs is NP-hard; it can be solved exactly in exponential time, or in fixed-parameter tractable time. In polynomial time, the minimum feedback arc set can be approximated to within a polylogarithmic approximation ratio, and maximum acyclic subgraphs can be approximated to within a constant factor. Both are hard to approximate closer than some constant factor, an inapproximability result that can be strengthened under the unique games conje
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https://en.wikipedia.org/wiki/K-means%20clustering
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k-means clustering is a method of vector quantization, originally from signal processing, that aims to partition n observations into k clusters in which each observation belongs to the cluster with the nearest mean (cluster centers or cluster centroid), serving as a prototype of the cluster. This results in a partitioning of the data space into Voronoi cells. k-means clustering minimizes within-cluster variances (squared Euclidean distances), but not regular Euclidean distances, which would be the more difficult Weber problem: the mean optimizes squared errors, whereas only the geometric median minimizes Euclidean distances. For instance, better Euclidean solutions can be found using k-medians and k-medoids.
The problem is computationally difficult (NP-hard); however, efficient heuristic algorithms converge quickly to a local optimum. These are usually similar to the expectation-maximization algorithm for mixtures of Gaussian distributions via an iterative refinement approach employed by both k-means and Gaussian mixture modeling. They both use cluster centers to model the data; however, k-means clustering tends to find clusters of comparable spatial extent, while the Gaussian mixture model allows clusters to have different shapes.
The unsupervised k-means algorithm has a loose relationship to the k-nearest neighbor classifier, a popular supervised machine learning technique for classification that is often confused with k-means due to the name. Applying the 1-nearest neigh
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https://en.wikipedia.org/wiki/Literal%20pool
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In computer science, and specifically in compiler and assembler design, a literal pool is a lookup table used to hold literals during assembly and execution.
Multiple (local) literal pools are typically used only for computer architectures that lack branch instructions for long jumps, or have a set of instructions optimized for shorter jumps. Examples of such architectures include the IBM System/360 and its successors, which had a number of instructions which took 12-bit address offsets. In this case, the compiler would create a literal table on every 4K page; any branches whose target was less than 4K bytes away could be taken immediately; longer branches required an address lookup via the literal table. The entries in the literal pool are placed into the object relocation table during assembly, and are then resolved at link edit time.
The ARM architecture also makes use of multiple local pools, as does AArch64, the 64-bit extension to the original ARM.
Another architecture making use of multiple local pools is C-SKY, a 32-bit architecture designed for embedded SoCs.
In certain ways, a literal pool resembles a TOC or a global offset table (GOT), except that the implementation is considerably simpler, and there may be multiple literal tables per object.
Perhaps the most common type of literal pool are the literal pools used by the LDR Rd,=const pseudo-instruction in ARM assembly language
and similar instructions in IBM System/360 assembly language,
which are compile
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https://en.wikipedia.org/wiki/Prepayment%20for%20service
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Prepaid refers to services paid for in advance. Examples include postage stamps, attorneys, tolls, public transit cards like the Greater London Oyster card, pay as you go cell phones, and stored-value cards such as gift cards and preloaded credit cards.
Prepaid services and goods are sometimes targeted to marginal customers by retailers.
Unlike postpaid or contract based services, prepaid accounts can be obtained with cash. As a result, they can be established by people who have minimal identification or poor credit ratings. Minors, immigrants, students, defaulters, and those on low incomes are typical prepaid customers.
Prepaid mobile phones
Recent statistics (OECD Communications Outlook 2005) indicate that 40% of the total mobile phone market in the OECD region consists of prepaid accounts. This service was invented by Portuguese provider TMN, while researching for a means to increase penetration of mobile technology by allowing anyone to buy a fully working (usually requiring a quick and simple activation process) mobile phone on any supermarket or electronics store. By removing the complications inherent to the contract system, this allowed the mobile communications user base to grow incredibly fast. In many countries this type of service became the predominant one, shortly after introduction, by providing both consumers and service providers with considerable advantages over the traditional method. In some countries, such as Italy or Mexico, market share of prepaid
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https://en.wikipedia.org/wiki/Famille%20rose
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Famille rose (French for "pink family") is a type of Chinese porcelain introduced in the 18th century and defined by pink overglaze enamel. It is a Western classification for Qing dynasty porcelain known in Chinese by various terms: fencai, ruancai, yangcai, and falangcai. The colour palette is thought to have been brought to China during the reign of Kangxi (1654–1722) by Western Jesuits who worked at the palace, but perfected only in the Yongzheng era when the finest pieces were made, and famille rose ware reached the peak of its technical excellence during the Qianlong period.
Although famille rose is named after its pink coloured enamel, the colour may actually range from pale pink to deep ruby. Apart from pink, a range of other soft colour palettes are also used in famille rose. The gradation of colours was produced by mixing coloured enamels with 'glassy white' (玻璃白, boli bai), an opaque white enamel (lead arsenate). Its range of colour was further extended by mixing different colours.
Famille rose was popular in the 18th and 19th century, and it continued to be made in the 20th century. Large quantities of famille rose porcelain were exported to Europe, United States and other countries, and many of these export wares were Jingdezhen porcelain decorated in Canton, and are known as "Canton famille rose". Porcelains with famille rose palette were also produced in European factories.
Terms
The term meaning "pink family" was introduced together with ("green family"
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https://en.wikipedia.org/wiki/Phytosterol
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Phytosterols are phytosteroids, similar to cholesterol, that serve as structural components of biological membranes of plants. They encompass plant sterols and stanols. More than 250 sterols and related compounds have been identified. Free phytosterols extracted from oils are insoluble in water, relatively insoluble in oil, and soluble in alcohols.
Phytosterol-enriched foods and dietary supplements have been marketed for decades. Despite well-documented LDL cholesterol-lowering effects from long-term consumption of phytosterols, there is insufficient evidence for an effect on cardiovascular diseases, fasting blood sugar, glycated hemoglobin, or overall mortality rate.
Structure
They have a fused polycyclic structure and vary in carbon side chains and / or presence or absence of a double bond (saturation). They are divided into 4,4-dimethyl phytosterols, 4-monomethyl phytosterols, and 4-desmethyl phytosterols based on the location of methyl groups at the carbon-4 position. Stanols are saturated sterols, having no double bonds in the sterol ring structure.
The molecule in the article lead is β-sitosterol. The nomenclature is shown on the right.
By removing carbon 242, campesterol is obtained.
By removing carbons 241 and 242, cholesterol is obtained.
Removing a hydrogen from carbons 22 and 23 yields stigmasterol (stigmasta-5,22-dien-3β-ol).
By hydrogenating the double bond between carbons 5 and 6, β-sitostanol (Stigmastanol) is obtained.
By hydrogenating the double bond bet
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https://en.wikipedia.org/wiki/Ambipolar%20diffusion
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Ambipolar diffusion (ambipolar: relating to or consisting of both electrons and positive ions moving in opposite directions) is diffusion of positive and negative species with opposite electrical charge due to their interaction via an electric field. In the case of ionic crystals, the fluxes of the diffusing species are coupled, while in a plasma the various species diffuse at the same rate.
Diffusion in plasmas
In plasma physics, ambipolar diffusion is closely related to the concept of quasineutrality. In most plasmas, the forces acting on the ions are different from those acting on the electrons, so naively one would expect one species to be transported faster than the other, whether by diffusion or convection or some other process. If such differential transport has a divergence, then it results in a change of the charge density. The latter will in turn create an electric field that can alter the transport of one or both species in such a way that they become equal.
The simplest example is a plasma localized in an unmagnetized vacuum. (See Inertial confinement fusion.) Both electrons and ions will stream outward with their respective thermal velocity. If the ions are relatively cold, their thermal velocity will be small. The thermal velocity of the electrons will be fast due to their high temperature and low mass: . As the electrons leave the initial volume, they will leave behind a positive charge density of ions, which will result in an outwardly-directed electric f
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https://en.wikipedia.org/wiki/Topological%20map
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In cartography, geology, and robotics, a topological map is a type of diagram that has been simplified so that only vital information remains and unnecessary detail has been removed. These maps lack scale, also distance and direction are subject to change and/or variation, but the topological relationship between points is maintained. A good example are the tube maps for the London Underground and the New York City Subway.
See also
Outline of cartography
References
Map types
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https://en.wikipedia.org/wiki/Ethyl%20Green
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The dye Ethyl Green (C.I. 42590; C27H35BrClN3) is a triarylmethane dye. It is soluble in water.
Ethyl green is made of crystal violet by adding an ethyl group; crystal violet is therefore a possible contaminant.
Methyl green is a closely related dye used as a stain in histology. Ethyl green is also used as a histological dye.
External links
Chemical data
References
Triarylmethane dyes
Staining dyes
Anilines
Quaternary ammonium compounds
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https://en.wikipedia.org/wiki/Ageia
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Ageia, founded in 2002, was a fabless semiconductor company. In 2004, Ageia acquired NovodeX, the company who created PhysX – a Physics Processing Unit chip capable of performing game physics calculations much faster than general purpose CPUs; they also licensed out the PhysX SDK (formerly NovodeX SDK), a large physics middleware library for game production.
Ageia was noted as being the first company to develop hardware designed to offload calculation of video game physics from the CPU to a separate chip, commercializing it in the form of the Ageia PhysX, a discrete PCI card. Soon after the Ageia implementation of their PhysX processor,
ATI and Nvidia announced their own physics implementations.
On September 1, 2005, AGEIA acquired Meqon, a physics development company based in Sweden. Known for its forward-looking features and multi-platform support, Meqon earned international acclaim for its physics technology incorporated in 3D Realms’ Duke Nukem Forever and Saber Interactive's TimeShift.
On February 4, 2008, Nvidia announced that it would acquire Ageia. On February 13, 2008, the merger was finalized.
The PhysX engine is now known as Nvidia PhysX, and has been adapted to be run on Nvidia's GPUs.
References
External links
AGEIA PhysX Physics Processing Unit Preview
AGEIA in 2007 – Is This the Year of the PPU?
BFG Ageia PhysX Card
PhysX In GRAW 2
2002 establishments in California
Companies based in Santa Clara, California
Companies disestablished in 2008
Defunct compa
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https://en.wikipedia.org/wiki/RCV
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RCV may stand for:
Rabbit calicivirus
Radio Club Venezolano, Venezuela
Ranked-choice voting (disambiguation)
Red cell volume, a concept related to hematocrit but concerning total rather than percentage
Refuse collection vehicle
Remote control vehicle
Riot control vehicle, see RCV-9
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https://en.wikipedia.org/wiki/Ryanodine%20receptor
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Ryanodine receptors (RyR for short) form a class of intracellular calcium channels in various forms of excitable animal tissue like muscles and neurons.
There are three major isoforms of the ryanodine receptor, which are found in different tissues and participate in different signaling pathways involving calcium release from intracellular organelles. The RYR2 ryanodine receptor isoform is the major cellular mediator of calcium-induced calcium release (CICR) in animal cells.
Etymology
The ryanodine receptors are named after the plant alkaloid ryanodine which shows a high affinity to them.
Isoforms
There are multiple isoforms of ryanodine receptors:
RyR1 is primarily expressed in skeletal muscle
RyR2 is primarily expressed in myocardium (heart muscle)
RyR3 is expressed more widely, but especially in the brain.
Non-mammalian vertebrates typically express two RyR isoforms, referred to as RyR-alpha and RyR-beta.
Many invertebrates, including the model organisms Drosophila melanogaster (fruitfly) and Caenorhabditis elegans, only have a single isoform. In non-metazoan species, calcium-release channels with sequence homology to RyRs can be found, but they are shorter than the mammalian ones and may be closer to IP3 Receptors.
Physiology
Ryanodine receptors mediate the release of calcium ions from the sarcoplasmic reticulum and endoplasmic reticulum, an essential step in muscle contraction. In skeletal muscle, activation of ryanodine receptors occurs via a physical coup
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https://en.wikipedia.org/wiki/Groundwater%20flow%20equation
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Used in hydrogeology, the groundwater flow equation is the mathematical relationship which is used to describe the flow of groundwater through an aquifer. The transient flow of groundwater is described by a form of the diffusion equation, similar to that used in heat transfer to describe the flow of heat in a solid (heat conduction). The steady-state flow of groundwater is described by a form of the Laplace equation, which is a form of potential flow and has analogs in numerous fields.
The groundwater flow equation is often derived for a small representative elemental volume (REV), where the properties of the medium are assumed to be effectively constant. A mass balance is done on the water flowing in and out of this small volume, the flux terms in the relationship being expressed in terms of head by using the constitutive equation called Darcy's law, which requires that the flow is laminar. Other approaches are based on Agent Based Models to incorporate the effect of complex aquifers such as karstic or fractured rocks (i.e. volcanic)
Mass balance
A mass balance must be performed, and used along with Darcy's law, to arrive at the transient groundwater flow equation. This balance is analogous to the energy balance used in heat transfer to arrive at the heat equation. It is simply a statement of accounting, that for a given control volume, aside from sources or sinks, mass cannot be created or destroyed. The conservation of mass states that, for a given increment of time (Δt
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https://en.wikipedia.org/wiki/Monochromatic%20triangle
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In graph theory and theoretical computer science, the monochromatic triangle problem is an algorithmic problem on graphs,
in which the goal is to partition the edges of a given graph into two triangle-free subgraphs. It is NP-complete but fixed-parameter tractable on graphs of bounded treewidth.
Problem statement
The monochromatic triangle problem takes as input an n-node undirected graph G(V,E) with node set V and edge set E.
The output is a Boolean value, true if the edge set E of G can be partitioned into two disjoint sets E1 and E2, such that both of the two subgraphs G1(V,E1) and G2(V,E2) are triangle-free graphs, and false otherwise. This decision problem is NP-complete.
Generalization to multiple colors
The problem may be generalized to triangle-free edge coloring, finding an assignment of colors to the edges of a graph so that no triangle has all three edges given the same color. The monochromatic triangle problem is the special case of triangle-free edge-coloring when there are exactly two colors available. If there exists a two-color triangle-free edge coloring, then the edges of each color form the two sets E1 and E2 of the monochromatic triangle problem. Conversely, if the monochromatic triangle problem has a solution, we can use one color for E1 and a second color for E2 to obtain a triangle-free edge coloring.
Connection to Ramsey's theorem
By Ramsey's theorem, for any finite number k of colors, there exists a number n such that complete graphs of n or more v
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https://en.wikipedia.org/wiki/Ceratonova%20shasta
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Ceratonova shasta (syn. Ceratomyxa shasta) is a myxosporean parasite that infects salmonid fish on the Pacific coast of North America. It was first observed at the Crystal Lake Hatchery, Shasta County, California, and has now been reported from Idaho, Oregon, Washington, British Columbia and Alaska.
Life history
In addition to the fish host, C. shasta infects a freshwater polychaete worm. Actinospores are released from the worm, and infect fish, on contact, in the water column. Neither horizontal (fish to fish), nor vertical (fish to egg) transmissions have been documented under laboratory conditions, suggesting that the worm host is necessary for completion of the life cycle.
Spores are released back into freshwater system after its fish host dies, however the complete life cycle, host and vector interaction is not fully understood (especially the ecology of the polychaete host).
Research indicates that the potential for infection is enhanced when water temperatures are high, water flow is low, or numbers of infectious C. shasta are relatively high. Infection rates appear to be higher in or below still water environments than riverine ones.
Pathology of infection
Clinical indications of infection in salmons include lethargy, loss of body mass, darkening of the skin, ascites, exophthalmia and kidney pustules, These symptoms vary from one salmonid species to another, and also depend on life stage of the host.
Internally, infection with C. shasta affects entire digestive t
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https://en.wikipedia.org/wiki/Anasa%20tristis
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Anasa tristis is a species of bug in the family Coreidae. It is a major pest of squash and pumpkins, found throughout North America, and is a vector of the cucurbit yellow vine disease bacterium. These bugs can emit an unpleasant odor when disturbed. It is commonly known as the squash bug but shares this name with certain other species.
Description
The adult Anasa tristis is a greyish-brown, somewhat flattened insect reaching a length of about and a width of . There is often a row of alternate brown and gold spots along the margin of the abdomen. Adults survive for three or four months.
Host plants
Anasa tristis can be found on various members of the gourd family Cucurbitaceae, but most often occurs on pumpkins and squashes. Some varieties and cultivars are more susceptible to attack than others. Research has shown that nymphs can grow to adulthood with varying degrees of success on different host plants; 70%, 49%, 14%, 0.3% and 0% survived to maturity on pumpkin, squash, watermelon, cucumber and cantaloupe melon respectively. Larvae that primarily fed on cucumbers were more likely to live longer than those who fed on water alone, although these larvae didn't gain any substantial amount of weight in its developmental stage.
Life cycle
In the southern part of its range, the adult female Anasa tristis lays two or three batches of about eighteen eggs, but in the northern part of the range it just lays a single batch. The eggs are oval, somewhat flattened and bronze in colour
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https://en.wikipedia.org/wiki/Marc%20Jacobs
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Marc Jacobs (born April 9, 1963) is an American fashion designer. He is the head designer for his own fashion label, Marc Jacobs, and formerly Marc by Marc Jacobs, a diffusion line, which was produced for approximately 15 years, before it was discontinued after the 2015 fall/winter collection. At its peak, it had over 200 retail stores in 80 countries. He was the creative director of the French design house Louis Vuitton from 1997 to 2014. Jacobs was on Time magazine's "2010 Time 100" list of the 100 most influential people in the world, and was #14 on Out magazine's 2012 list of "50 Most Powerful Gay Men and Women in America". He married his longtime partner Charly Defrancesco on April 6, 2019.
Early life and education
Jacobs was born to a non-observant Jewish family in New York City. When he was seven, his father, an agent at the William Morris Agency, died. His mother, who remarried three times, was, according to Jacobs, "mentally ill" and "didn't really take care of her kids." As a teenager, he went to live with his paternal grandmother on the Upper West Side, in an apartment in the Majestic on Central Park West.
Jacobs grew up in Teaneck, New Jersey, and attended Teaneck High School.
He attended the High School of Art and Design and studied at Parsons School of Design in New York. While at Parsons in 1984, he won the Perry Ellis & Chester Weinberg Gold Thimble Award, and Design Student of the Year. In 1987, he became the youngest designer ever to receive the Council
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https://en.wikipedia.org/wiki/Slope%20field
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A slope field (also called a direction field) is a graphical representation of the solutions to a first-order differential equation of a scalar function. Solutions to a slope field are functions drawn as solid curves. A slope field shows the slope of a differential equation at certain vertical and horizontal intervals on the x-y plane, and can be used to determine the approximate tangent slope at a point on a curve, where the curve is some solution to the differential equation.
Definition
Standard case
The slope field can be defined for the following type of differential equations
which can be interpreted geometrically as giving the slope of the tangent to the graph of the differential equation's solution (integral curve) at each point (x, y) as a function of the point coordinates.
It can be viewed as a creative way to plot a real-valued function of two real variables as a planar picture. Specifically, for a given pair , a vector with the components is drawn at the point on the -plane. Sometimes, the vector is normalized to make the plot better looking for a human eye. A set of pairs making a rectangular grid is typically used for the drawing.
An isocline (a series of lines with the same slope) is often used to supplement the slope field. In an equation of the form , the isocline is a line in the -plane obtained by setting equal to a constant.
General case of a system of differential equations
Given a system of differential equations,
the slope field is an array
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https://en.wikipedia.org/wiki/Joule%20expansion
|
The Joule expansion (also called free expansion) is an irreversible process in thermodynamics in which a volume of gas is kept in one side of a thermally isolated container (via a small partition), with the other side of the container being evacuated. The partition between the two parts of the container is then opened, and the gas fills the whole container.
The Joule expansion, treated as a thought experiment involving ideal gases, is a useful exercise in classical thermodynamics. It provides a convenient example for calculating changes in thermodynamic quantities, including the resulting increase in entropy of the universe (entropy production) that results from this inherently irreversible process. An actual Joule expansion experiment necessarily involves real gases; the temperature change in such a process provides a measure of intermolecular forces.
This type of expansion is named after James Prescott Joule who used this expansion, in 1845, in his study for the mechanical equivalent of heat, but this expansion was known long before Joule e.g. by John Leslie, in the beginning of the 19th century, and studied by Joseph-Louis Gay-Lussac in 1807 with similar results as obtained by Joule.
The Joule expansion should not be confused with the Joule–Thomson expansion or throttling process which refers to the steady flow of a gas from a region of higher pressure to one of lower pressure via a valve or porous plug.
Description
The process begins with gas under some pressure, , at
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https://en.wikipedia.org/wiki/2-6-6-2
|
Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a is a locomotive with one pair of unpowered leading wheels, followed by two sets of three pairs of powered driving wheels and one pair of trailing wheels. The wheel arrangement was principally used on Mallet-type articulated locomotives, although some tank locomotive examples were also built. A Garratt locomotive or Golwé locomotive with the same wheel arrangement is designated since both engine units are pivoting.
Under the UIC classification the wheel arrangement is referred to as (1'C)C1' for Mallet locomotives.
Overview
The 2-6-6-2 wheel arrangement was most often used for articulated compound steam Mallet locomotives. In a compound Mallet, the rear set of coupled wheels are driven by the smaller high pressure cylinders, from which spent steam is then fed to the larger low pressure cylinders that drive the front set of coupled wheels.
This type of locomotive was commonly used in North America on logging railroads. The 2-6-6-2 wheel arrangement was also used in South Africa and the Soviet Union.
Usage
Serbia
The Serbian government used a Mallet articulated compound locomotive for freight service on narrow gauge. It was built for the Serbian government by the American Locomotive Company (ALCO).
South Africa
The South African Railways (SAR) operated 22 Mallet locomotives with this wheel arrangement, spread over five classes, all of them built to .
In March 1910, the Central
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https://en.wikipedia.org/wiki/Antimetabolite
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An antimetabolite is a chemical that inhibits the use of a metabolite, which is another chemical that is part of normal metabolism. Such substances are often similar in structure to the metabolite that they interfere with, such as the antifolates that interfere with the use of folic acid; thus, competitive inhibition can occur, and the presence of antimetabolites can have toxic effects on cells, such as halting cell growth and cell division, so these compounds are used as chemotherapy for cancer.
Function
Cancer treatment
Antimetabolites can be used in cancer treatment, as they interfere with DNA production and therefore cell division and tumor growth. Because cancer cells spend more time dividing than other cells, inhibiting cell division harms tumor cells more than other cells. Antimetabolite drugs are commonly used to treat leukemia, cancers of the breast, ovary, and the gastrointestinal tract, as well as other types of cancers. In the Anatomical Therapeutic Chemical Classification System antimetabolite cancer drugs are classified under L01B.
Antimetabolites generally impair DNA replication machinery, either by incorporation of chemically altered nucleotides or by depleting the supply of deoxynucleotides needed for DNA replication and cell proliferation.
Examples of cancer drug antimetabolites include, but are not limited to the following:
5-Fluorouracil (5-FU)
6-Mercaptopurine (6-MP)
Capecitabine (Xeloda®)
Cytarabine (Ara-C®)
Floxuridine
Fludarabine
Gemcitabine (Gemza
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https://en.wikipedia.org/wiki/Quantum%20sort
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A quantum sort is any sorting algorithm that runs on a quantum computer. Any comparison-based quantum sorting algorithm would take at least steps, which is already achievable by classical algorithms. Thus, for this task, quantum computers are no better than classical ones, and should be disregarded when it comes to time complexity. However, in space-bounded sorts, quantum algorithms outperform their classical counterparts.
References
Sorting algorithms
Quantum algorithms
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https://en.wikipedia.org/wiki/Cancer%20procoagulant
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Cancer procoagulant is a hypothesised protein, most likely a cysteine protease enzyme (), that occurs only in fetal and malignant cells. Its activity appears to be the activation of factor X, one of the coagulation factors, and would account for the increased incidence of thrombosis in cancer patients. Tissue factor (TF) is also known to be present at increased levels around malignant cells.
References
External links
EC 3.4.22
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https://en.wikipedia.org/wiki/Forest%20dynamics
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Forest dynamics describes the underlying physical and biological forces that shape and change a forest ecosystem. The continuous state of change in forests can be summarized with two basic elements: disturbance and succession.
Disturbance
Forest disturbances are events that cause change in the structure and composition of a forest ecosystem, beyond the growth and death of individual organisms. Disturbances can vary in frequency and intensity, and include natural disasters such as fire, landslides, wind, volcanic eruptions, rare meteor impacts, outbreaks of insects, fungi, and other pathogens, animal-caused effects such as grazing and trampling, and anthropogenic disturbances such as warfare, logging, pollution, the clearing of land for urbanization or agriculture, and the introduction of invasive species. Not all disturbances are destructive or negative to the overall forest ecosystem. Many natural disturbances allow for renewal and growth and often release necessary nutrients.
Small-scale disturbances are the key to creating and maintaining diversity and heterogeneity within a forest. Small-scale disturbances are events such as single-tree blowdowns, which create gaps that let light through the canopy to the understory and forest floor. This available light allows early-successional shade-intolerant species to colonize and maintain a population within the dominant forest, leading to the complex spatial mosaic forest structure recognized as old-growth. This process is refe
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https://en.wikipedia.org/wiki/Implicit
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Implicit may refer to:
Mathematics
Implicit function
Implicit function theorem
Implicit curve
Implicit surface
Implicit differential equation
Other uses
Implicit assumption, in logic
Implicit-association test, in social psychology
Implicit bit, in floating-point arithmetic
Implicit learning, in learning psychology
Implicit memory, in long-term human memory
Implicit solvation, in computational chemistry
Implicit stereotype (implicit bias), in social identity theory
Implicit type conversion, in computing
See also
Implicit and explicit atheism, types of atheism coined by George H. Smith
Implication (disambiguation)
Implicature
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https://en.wikipedia.org/wiki/Polar%20capsule
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Polar capsules are structures found in the valves of Myxosporean parasites, which contain the polar filament. The polar capsule is constructed of a proteinaceous and a polysaccharide layer, both layers of which continue into the polar filament.
The mouth of the capsule is covered with a cap-like structure. This structure may function as a stopper, its digestion in the alimentary tract possibly triggering the discharge of the polar filaments.
Two ideas have been proposed to explain the eversion of the polar filaments. Firstly, that the hydrostatic pressure in the polar capsule pushes the filament out, rather like the cnidocyst of jellyfish. The second is that extrusion is an active process involving contractile proteins and is calcium-dependent (Uspenskaya, 1982).
References
Uspenskaya, A.V. (1984). Cytology of myxosporidia. Nauka, Leningrad. 122pp.
Animal anatomy
Myxozoa
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https://en.wikipedia.org/wiki/Standard%20Modular%20System
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The Standard Modular System (SMS) is a system of standard transistorized circuit boards and mounting racks developed by IBM in the late 1950s, originally for the IBM 7030 Stretch. They were used throughout IBM's second-generation computers, peripherals, the 7000 series, the 1400 series, and the 1620. SMS was superseded by Solid Logic Technology (SLT) introduced with System/360 in 1964, however they remained in use with legacy systems through the 1970s.
Overview
Many IBM peripheral devices that are part of System/360, but were adapted from second-generation designs, continued to use SMS circuitry instead of the newer SLT. These included the 240x-series tape drives and controllers, the 2540 card reader/punch and 1403N1 printer, and the 2821 Integrated Control Unit for the 1403 and 2540. A few SMS cards used in System/360 peripheral devices even have SLT-type hybrid ICs mounted on them (see right).
SMS cards are constructed of individual discrete components mounted on single-sided paper-epoxy printed circuit boards. Single-width cards are 2.5 inches wide by 4.5 inches tall by 0.056 inches thick, with a 16-pin gold plated edge connector. Double-width cards are 5.375 inches wide by 4.5 inches tall, with two 16-pin gold plated edge connectors. Contacts are labeled A–R (skipping I and O) on the first edge connector, and S–Z, 1–8 on the second.
The cards are plugged into a card-cage back-plane and edge connector contacts connected to wire wrap pins. All interconnections are made
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https://en.wikipedia.org/wiki/Instruction%20selection
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In computer science, instruction selection is the stage of a compiler backend that transforms its middle-level intermediate representation (IR) into a low-level IR. In a typical compiler, instruction selection precedes both instruction scheduling and register allocation; hence its output IR has an infinite set of pseudo-registers (often known as temporaries) and may still be – and typically is – subject to peephole optimization. Otherwise, it closely resembles the target machine code, bytecode, or assembly language.
For example, for the following sequence of middle-level IR code
t1 = a
t2 = b
t3 = t1 + t2
a = t3
b = t1
a good instruction sequence for the x86 architecture is
MOV EAX, a
XCHG EAX, b
ADD a, EAX
For a comprehensive survey on instruction selection, see.
Macro expansion
The simplest approach to instruction selection is known as macro expansion or interpretative code generation. A macro-expanding instruction selector operates by matching templates over the middle-level IR. Upon a match the corresponding macro is executed, using the matched portion of the IR as input, which emits the appropriate target instructions. Macro expansion can be done either directly on the textual representation of the middle-level IR, or the IR can first be transformed into a graphical representation which is then traversed depth-first. In the latter, a template matches one or more adjacent nodes in the graph.
Unless the target machine is very simple, macro expansion in isolation ty
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https://en.wikipedia.org/wiki/Bangiophyceae
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Bangiophyceae is a class of red algae. In some classifications it is merged with the Florideophyceae to form the Rhodophyceae. The Bangiophyceae, as defined traditionally, are paraphyletic. Their taxonomic identification has been difficult because of a lack of distinct morphological features, and the presumed morphological plasticity of the species. Molecular tools are required to elucidate the relationships within this assemblage.
It is still used by some sources, and defined sensu stricto (including Bangia and Porphyra but not the species included in Florideophyceae) is considered a valid clade.
References
Red algae classes
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https://en.wikipedia.org/wiki/Phaser%20%28effect%29
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A phaser is an electronic sound processor used to filter a signal by creating a series of peaks and troughs in the frequency spectrum. The position of the peaks and troughs of the waveform being affected is typically modulated by an internal low-frequency oscillator so that they vary over time, creating a sweeping effect.
Phasers are often used to give a "synthesized" or electronic effect to natural sounds, such as human speech. The voice of C-3PO from Star Wars was created by taking the actor's voice and treating it with a phaser.
Process
The electronic phasing effect is created by splitting an audio signal into two paths. One path treats the signal with an all-pass filter, which preserves the amplitude of the original signal and alters the phase. The amount of change in phase depends on the frequency. When signals from the two paths are mixed, the frequencies that are out of phase will cancel each other out, creating the phaser's characteristic notches. Changing the mix ratio changes the depth of the notches; the deepest notches occur when the mix ratio is 50%.
The definition of phaser typically excludes such devices where the all-pass section is a delay line; such a device is called a flanger. Using a delay line creates an unlimited series of equally spaced notches and peaks. It is possible to cascade a delay line with another type of all-pass filter. This combines the unlimited number of notches from the flanger with the uneven spacing of the phaser.
Structure
Tradi
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https://en.wikipedia.org/wiki/MARSIS
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MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) is a low frequency, pulse-limited radar sounder and altimeter developed by the University of Rome La Sapienza and Alenia Spazio (today Thales Alenia Space Italy). The Italian MARSIS instrument, which is operated by the European Space Agency, is operational and orbits Mars as an instrument for the ESA's Mars Express exploration mission.
The MARSIS Principal Investigator is Giovanni Picardi from the University of Rome "La Sapienza", Italy. It features ground-penetrating radar capabilities, which uses synthetic aperture technique and a secondary receiving antenna to isolate subsurface reflections. MARSIS identified buried basins on Mars. MARSIS was funded by ASI (Italy) and NASA (USA). The processor runs the real-time operating system EONIC Virtuoso.
Deployment
On May 4, 2005, Mars Express deployed the first of its two 20-metre-long radar booms for the MARSIS experiment. At first the boom didn't lock fully into place; however, exposing it to sunlight for a few minutes on May 10 fixed the glitch. The second 20 m boom was successfully deployed on June 14. Both 20 m booms were needed to create a 40 m dipole antenna for MARSIS to work; a less crucial 7-meter-long monopole antenna was deployed on June 17. The radar booms were originally scheduled to be deployed in April 2004, but this was delayed out of fear that the deployment could damage the spacecraft through a whiplash effect. Due to the delay it was dec
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https://en.wikipedia.org/wiki/Waves%20in%20plasmas
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In plasma physics, waves in plasmas are an interconnected set of particles and fields which propagate in a periodically repeating fashion. A plasma is a quasineutral, electrically conductive fluid. In the simplest case, it is composed of electrons and a single species of positive ions, but it may also contain multiple ion species including negative ions as well as neutral particles. Due to its electrical conductivity, a plasma couples to electric and magnetic fields. This complex of particles and fields supports a wide variety of wave phenomena.
The electromagnetic fields in a plasma are assumed to have two parts, one static/equilibrium part and one oscillating/perturbation part. Waves in plasmas can be classified as electromagnetic or electrostatic according to whether or not there is an oscillating magnetic field. Applying Faraday's law of induction to plane waves, we find , implying that an electrostatic wave must be purely longitudinal. An electromagnetic wave, in contrast, must have a transverse component, but may also be partially longitudinal.
Waves can be further classified by the oscillating species. In most plasmas of interest, the electron temperature is comparable to or larger than the ion temperature. This fact, coupled with the much smaller mass of the electron, implies that the electrons move much faster than the ions. An electron mode depends on the mass of the electrons, but the ions may be assumed to be infinitely massive, i.e. stationary. An ion mode depe
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https://en.wikipedia.org/wiki/Diadochite
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Diadochite is a phospho-sulfate mineral. It is a secondary mineral formed by the weathering and hydration of other minerals. Its formula is Fe2(PO4)(SO4)OH·5H2O. Well crystallized forms are referred to as destinezite, which has been given official recognition by the International Mineralogical Association with diadochite being the poorly formed to amorphous variety.
It has a greenish yellow to brown colour and forms nodules or crusts. Its appearance has been compared to cauliflower.
Identified originally in Belgium in 1831, it has been found in many places throughout the world.
It occurs as a secondary mineral in mineral gossans, coal deposits, phosphate rich pegmatites and cave guano deposits.
References
Webmineral
Iron(III) minerals
Phosphate minerals
Sulfate minerals
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https://en.wikipedia.org/wiki/Saturation%20current
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The saturation current (or scale current), more accurately the reverse saturation current, is the part of the reverse current in a semiconductor diode caused by diffusion of minority carriers from the neutral regions to the depletion region. This current is almost independent of the reverse voltage.
The reverse bias saturation current for an ideal p–n diode is:
where
is elementary charge
is the cross-sectional area
are the diffusion coefficients of holes and electrons, respectively,
are the donor and acceptor concentrations at the n side and p side, respectively,
is the intrinsic carrier concentration in the semiconductor material,
are the carrier lifetimes of holes and electrons, respectively.
Increase in reverse bias does not allow the majority charge carriers to diffuse across the junction. However, this potential helps some minority charge carriers in crossing the junction. Since the minority charge carriers in the n-region and p-region are produced by thermally generated electron-hole pairs, these minority charge carriers are extremely temperature dependent and independent of the applied bias voltage. The applied bias voltage acts as a forward bias voltage for these minority charge carriers and a current of small magnitude flows in the external circuit in the direction opposite to that of the conventional current due to the moment of majority charge carriers.
Note that the saturation current is not a constant for a given device; it varies with temperature;
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https://en.wikipedia.org/wiki/Welcome%20to%20Mooseport
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Welcome to Mooseport is a 2004 American political satire comedy film directed by Donald Petrie, and starring Ray Romano and Gene Hackman in his final film role. It was filmed in Jackson's Point, Ontario and Port Perry, Ontario.
Plot
Former President of the United States Monroe "Eagle" Cole retires to his vacation home in the town of Mooseport, Maine, to escape from his ex-wife Charlotte. Harold "Handy" Harrison is the town's local hardware store owner and plumber. Handy’s job keeps him so busy that he has neglected his relationship with his girlfriend and the town veterinarian Sally Mannis, who is on the verge of dumping him.
After the death of the town mayor, the town council decides to approach former president Cole about running for the office. Cole agrees because, if he is mayor, his Mooseport house can serve as his office and, therefore, can no longer be divided up or sold off in his divorce settlement. As a surprise to Cole, Handy’s name has also been entered into the race. When Harrison finds out Cole is running, he decides to withdraw, until he witnesses Cole make a pass at Sally. Handy believes that, by becoming mayor, he can show Sally he is a mature decision maker and win back her heart.
Tempers rise following the arrival of Cole's ex-wife and campaign spoiler Charlotte. Cole's team, led by long-time executive secretary Grace Sutherland and presidential aide Will Bullard, bring in strong support in the form of campaign strategist Bert Langdon, who is looking for
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https://en.wikipedia.org/wiki/Thomas%20Schneeweis
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Thomas Schneeweis, professor of finance at the School of Management, University of Massachusetts Amherst, Amherst, MA, is also the director of the Center for International Securities and Derivatives Markets there.
He is president of Alternative Investment Analytics, LLC, which he established in 2005, as a consultancy in the fields of multi-advisor hedge fund creation and asset allocation.
He is a frequent speaker at academic and financial-services industry events and is often quoted press (i.e. the Financial Times, Business Week and the Wall Street Journal.
References
External links
University of Massachusetts Amherst faculty
Living people
Year of birth missing (living people)
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https://en.wikipedia.org/wiki/Suhas%20Patil
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Suhas S. Patil (born 1944) is an Indian-American entrepreneur, academic, and venture capitalist. He founded Cirrus Logic, a fabless semiconductor company. Patil's work has covered computer architecture, parallel processing computers, very-large-scale integration devices, and integrated circuit design automation software. He also serves on the boards of The Tech Museum and the World Affairs Council of Northern California. He is known for describing the "cigarette smokers problem" for concurrent computing in 1971.
Early life and education
Patil grew up in Jamshedpur, India. His father was the first person in the family to go to a university and get an engineering degree and worked at Tata Steel while Patil was growing up. Patil went to study intermediate science at St. Xavier's College, Kolkata and then to the Indian Institute of Technology Kharagpur for his bachelor's degree in electrical engineering. He attended the Massachusetts Institute of Technology for his masters and doctorate degrees, graduating in 1967 and 1970 respectively.
Career
From 1970 until 1975, Patil was assistant professor of electrical engineering at Massachusetts Institute of Technology. While at MIT, he also served as assistant director of Project MAC (Multi-Access Computer), the largest computer science laboratory in the U.S, where the timesharing computer system was developed. At MIT, he worked in the area of computer architecture and related topics. As a gift to the Massachusetts Institute of Techn
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https://en.wikipedia.org/wiki/Synthase
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In biochemistry, a synthase is an enzyme that catalyses a synthesis process.
Note that, originally, biochemical nomenclature distinguished synthetases and synthases. Under the original definition, synthases do not use energy from nucleoside triphosphates (such as ATP, GTP, CTP, TTP, and UTP), whereas synthetases do use nucleoside triphosphates. However, the Joint Commission on Biochemical Nomenclature (JCBN) dictates that 'synthase' can be used with any enzyme that catalyzes synthesis (whether or not it uses nucleoside triphosphates), whereas 'synthetase' is to be used synonymously with 'ligase'.
Examples
ATP synthase
Citrate synthase
Tryptophan synthase
Pseudouridine synthase
Fatty acid synthase
Cellulose synthase (UDP-forming)
Cellulose synthase (GDP-forming)
References
Lyases
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https://en.wikipedia.org/wiki/High-functioning%20autism
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High-functioning autism (HFA) was historically an autism classification where a person exhibits no intellectual disability, but may experience difficulty in communication, emotion recognition, expression, and social interaction.
HFA has never been included in either the American Psychiatric Association's Diagnostic and Statistical Manual (DSM) or the World Health Organization's International Classification of Diseases (ICD), the two major classification and diagnostic guidelines for psychiatric conditions.
Characterization
High-functioning autism is characterized by features similar to those of Asperger syndrome. The defining characteristic recognized by psychologists is a significant delay in the development of early speech and language skills, before the age of three years. The diagnostic criteria of Asperger syndrome exclude a general language delay.
Further differences in features of people with high-functioning autism from those with Asperger syndrome include the following:
Lower verbal reasoning ability
Better visual/spatial skills (Being uniquely artistically talented)
Less deviating locomotion (e.g. clumsiness)
Problems functioning independently
Curiosity and interest for many different things
Not as good at empathizing with other people
Male to female ratio (4:1) much smaller
Comorbidities
Individuals with autism spectrum disorders, including high-functioning autism, risk developing symptoms of anxiety. While anxiety is one of the most commonly occurring
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https://en.wikipedia.org/wiki/Slot%20antenna
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A slot antenna consists of a metal surface, usually a flat plate, with one or more holes or slots cut out. When the plate is driven as an antenna by an applied radio frequency current, the slot radiates electromagnetic waves in a way similar to a dipole antenna. The shape and size of the slot, as well as the driving frequency, determine the radiation pattern. Slot antennas are usually used at UHF and microwave frequencies at which wavelengths are small enough that the plate and slot are conveniently small. At these frequencies, the radio waves are often conducted by a waveguide, and the antenna consists of slots in the waveguide; this is called a slotted waveguide antenna. Multiple slots act as a directive array antenna and can emit a narrow fan-shaped beam of microwaves. They are used in standard laboratory microwave sources used for research, UHF television transmitting antennas, antennas on missiles and aircraft, sector antennas for cellular base stations, and particularly marine radar antennas. A slot antenna's main advantages are its size, design simplicity, and convenient adaptation to mass production using either waveguide or PC board technology.
Structure
As shown by H. G. Booker in 1946, from Babinet's principle in optics a slot in a metal plate or waveguide has the same radiation pattern as a driven rod antenna whose rod is the same shape as the slot, with the exception that the electric field and magnetic field directions are interchanged; the antenna is
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https://en.wikipedia.org/wiki/Survey%20of%20Activities%20of%20Young%20People
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The Survey of Activities of Young People (SAYP) is a national household-based survey of work-related activities among South African children, conducted for the first time in 1999 by Statistics South Africa.
The official results were released in October 2002, and provides a national, quantitative picture. It also gives an indication of the different categories of working children who are most in need or who are at the greatest risk of exploitation in work and employment.
The survey constituted the first step in the development of the South African Child Labour Programme of Action which was provisionally adopted in September 2003.
A household-based survey cannot pick up some of the worst forms of child labour — for this reason, qualitative research projects are undertaken or planned by the "Towards the Elimination of the worst forms of Child Labour" (TECL) Programme.
External links
The results of the SAYP from the Department of Labour.
Child Labour Programme of Action (South Africa)
1999 establishments in South Africa
Demographics of South Africa
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https://en.wikipedia.org/wiki/Phorone
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Phorone, or diisopropylidene acetone, is a yellow crystalline substance with a geranium odor, with formula or .
Preparation
It was first obtained in 1837 in impure form by the French chemist Auguste Laurent, who called it "camphoryle". In 1849, the French chemist Charles Frédéric Gerhardt and his student Jean Pierre Liès-Bodart prepared it in a pure state and named it "phorone". On both occasions it was produced by ketonization through the dry distillation of the calcium salt of camphoric acid.
It is now typically obtained by the acid-catalysed twofold aldol condensation of three molecules of acetone. Mesityl oxide is obtained as an intermediate and can be isolated.
Crude phorone can be purified by repeated recrystallization from ethanol or ether, in which it is soluble.
Reactions
Phorone can condense with ammonia to form triacetone amine.
See also
Isophorone
References
Merck Index, 11th Edition, 7307.
External links
International Chemical Safety Cards
Ketones
Alkene derivatives
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https://en.wikipedia.org/wiki/0-8-2
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Under the Whyte notation for the classification of steam locomotives, 0-8-2 represents the wheel arrangement of no leading wheels, eight powered and coupled driving wheels on four axles, and two trailing wheels on one axle (usually in a trailing truck).
Other equivalent classifications are:
UIC classification (also known as German classification and Italian classification): D1,
French classification: 041,
Turkish classification: 45,
Swiss classification: 4/5.
Usage
This has been a relatively unusual wheel arrangement on mainline railways
United Kingdom
In the United Kingdom, a number of tank locomotive designs were built of the 0-8-2 type, including the London and North Eastern Railway (LNER) R1 class, designed by Henry A. Ivatt and built originally for the Great Northern Railway as their class L1. These locomotives were intended for suburban passenger service, but did not prove satisfactory, so they ended up on freight service.
Other examples include the LNWR 1185 Class and the Port Talbot Railway 0-8-2T (Cooke) and Port Talbot Railway 0-8-2T (Sharp Stewart).
Australia
Dorrigo Steam Railway and Museum has preserved Avonside 0-8-2 Tank Locomotive number 14, formerly operated by South Maitland Railways collieries line in the Hunter Valley of N.S.W. Number 14 is operational, it was built in 1909 in Bristol. The design combination of this 0-8-2 tank Locomotive and the N.S.W. Government Railways 50 class 2-8-0, produced the South Maitland Railways 10 class 2-8-2 Tank
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https://en.wikipedia.org/wiki/3%2C3%27-Diaminobenzidine
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3,3′-Diaminobenzidine (DAB) is an organic compound with the formula (C6H3(NH2)2)2. This derivative of benzidine is a precursor to polybenzimidazole, which forms fibers that are renowned for their chemical and thermal stability. As its water-soluble tetrahydrochloride, DAB has been used in immunohistochemical staining of nucleic acids and proteins.
Structure
DAB is symmetric about the central carbon bond between both ring structures. In the crystal, the rings of each molecule are co-planar and the amine units connect molecules to form an intermolecular 3-dimensional hydrogen bond network.
Preparation
Diaminobenzidine, which is commercially available, is prepared by treating 3,3′-dichlorobenzidine with ammonia with a copper catalyst at high temperature and pressure, followed by acidic workup.
An alternate synthesis route involves the diacylation of benzidine with acetic anhydride under basic conditions:
(NH2)C6H4C6H4(NH2) + 2 (CH3CO)2O ⟶ (NHCOCH3)C6H4C6H4(NHCOCH3) + 2 CH3CO2H
The diacetylated compound then undergoes nitration with nitric acid to produce an ortho-dinitro compound due to the ortho-directing acetyl substituents:
(NHCOCH3)C6H4C6H4(NHCOCH3) + 2HNO3 ⟶ (O2N)(NHCOCH3)C6H3C6H3(NHCOCH3)(NO2) + 2H2O
The acetyl groups are then removed through saponification:
(O2N)(NHCOCH3)C6H3C6H3(NHCOCH3)(NO2) + 2NaOH ⟶ (O2N)(NH2)C6H3C6H3(NH2)(NO2) + 2(NaOCOCH3)
The dinitrobenzidine compound is then reduced with hydrochloric acid and iron to produce 3,3′-diaminobenzidine:
3(O2N)(N
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https://en.wikipedia.org/wiki/Apollo%20Diamond
|
Apollo Diamond Inc. was a company based in Boston, Massachusetts that was able to produce nearly flawless single crystal diamond wafers and crystals for potential use in the optoelectronics, nanotechnology, and consumer gem markets. The company used chemical vapor deposition (CVD) for the production of their gem-sized synthetic diamond crystals, and obtained several U.S. patents on the process. The company's techniques were able to produce colorless gems, in contrast to previous diamond-making techniques which usually produced colored diamonds.
In 2011, many assets of Apollo Diamond were acquired by Scio Diamond Technology Corporation, which said it would use the technology at its South Carolina facility.
See also
List of synthetic diamond manufacturers
Notes
External linksreat
SCIO Diamond website
The New Diamond Age, Wired, September 11, 2003
Diamonds on Demand, Smithsonian, June, 2008
US Patents awarded to Apollo Diamond
USAToday: Nanotechnology's everywhere, May 2005
Synthetic diamond
|
https://en.wikipedia.org/wiki/Biochemical%20cascade
|
A biochemical cascade, also known as a signaling cascade or signaling pathway, is a series of chemical reactions that occur within a biological cell when initiated by a stimulus. This stimulus, known as a first messenger, acts on a receptor that is transduced to the cell interior through second messengers which amplify the signal and transfer it to effector molecules, causing the cell to respond to the initial stimulus. Most biochemical cascades are series of events, in which one event triggers the next, in a linear fashion. At each step of the signaling cascade, various controlling factors are involved to regulate cellular actions, in order to respond effectively to cues about their changing internal and external environments.
An example would be the coagulation cascade of secondary hemostasis which leads to fibrin formation, and thus, the initiation of blood coagulation. Another example, sonic hedgehog signaling pathway, is one of the key regulators of embryonic development and is present in all bilaterians. Signaling proteins give cells information to make the embryo develop properly. When the pathway malfunctions, it can result in diseases like basal cell carcinoma. Recent studies point to the role of hedgehog signaling in regulating adult stem cells involved in maintenance and regeneration of adult tissues. The pathway has also been implicated in the development of some cancers. Drugs that specifically target hedgehog signaling to fight diseases are being actively devel
|
https://en.wikipedia.org/wiki/Grapher
|
Grapher is a computer program bundled with macOS since version 10.4 that is able to create 2D and 3D graphs from simple and complex equations. It includes a variety of samples ranging from differential equations to 3D-rendered Toroids and Lorenz attractors. It is also capable of dealing with functions and compositions of them. One can edit the appearance of graphs by changing line colors, adding patterns to rendered surfaces, adding comments, and changing the fonts and styles used to display them. Grapher is able to create animations of graphs by changing constants or rotating them in space.
History
Before Grapher and Mac OS X, Mac OS 9 was bundled with Pacific Tech's Graphing Calculator, a similar program to Grapher that had been included with over 20 million Macintoshes since 1994 with System 7. No versions of Mac OS X prior to Mac OS X v10.4 included a bundled graphing calculator application. On July 22, 2004, Apple bought Arizona Software's "Curvus Pro X," and renamed it “Graphing Calculator”, before deciding on “Grapher”. The news was publicly announced on September 15, 2004 at AppleInsider.
Version 2.0 of Grapher was bundled with Mac OS X v10.5, and version 2.1 with Mac OS X v10.6. It was notable for being one of the few applications bundled with 10.6 to ship without 64-bit support. As of OS X 10.9, it became a 64-bit application.
Features
Grapher is a graphing calculator capable of creating both 2D graphs including classic (linear-linear), polar coordinates, linea
|
https://en.wikipedia.org/wiki/Hypoexponential%20distribution
|
In probability theory the hypoexponential distribution or the generalized Erlang distribution is a continuous distribution, that has found use in the same fields as the Erlang distribution, such as queueing theory, teletraffic engineering and more generally in stochastic processes. It is called the hypoexponetial distribution as it has a coefficient of variation less than one, compared to the hyper-exponential distribution which has coefficient of variation greater than one and the exponential distribution which has coefficient of variation of one.
Overview
The Erlang distribution is a series of k exponential distributions all with rate . The hypoexponential is a series of k exponential distributions each with their own rate , the rate of the exponential distribution. If we have k independently distributed exponential random variables , then the random variable,
is hypoexponentially distributed. The hypoexponential has a minimum coefficient of variation of .
Relation to the phase-type distribution
As a result of the definition it is easier to consider this distribution as a special case of the phase-type distribution. The phase-type distribution is the time to absorption of a finite state Markov process. If we have a k+1 state process, where the first k states are transient and the state k+1 is an absorbing state, then the distribution of time from the start of the process until the absorbing state is reached is phase-type distributed. This becomes the hypoexponential if
|
https://en.wikipedia.org/wiki/Philip%20Dawid
|
Alexander Philip Dawid (pronounced 'David'; born 1 February 1946) is Emeritus Professor of Statistics of the University of Cambridge, and a Fellow of Darwin College, Cambridge. He is a leading proponent of Bayesian statistics.
Education
Dawid was educated at the City of London School, Trinity Hall, Cambridge and Darwin College, Cambridge.
Career and research
Dawid has made fundamental contributions to both the philosophical underpinnings and the practical applications of statistics. His theory of conditional independence is a keystone of modern statistical theory and methods, and he has demonstrated its usefulness in a host of applications, including computation in probabilistic expert systems, causal inference, and forensic identification.
Dawid was lecturer in statistics at University College London from 1969 to 1978. He was subsequently Professor of Statistics at City University, London until 1981, when he returned to UCL as a reader, becoming Pearson Professor of Statistics there in 1982. He moved to the University of Cambridge where he was appointed Professor of Statistics in 2007, retiring in 2013.
Awards and honours
He was elected a member of the International Statistical Institute in 1978, and a Chartered Statistician of the Royal Statistical Society in 1993. He was editor of Biometrika from 1992 to 1996 and President of the International Society for Bayesian Analysis in 2000. He is also an elected Fellow of the Institute of Mathematical Statistics. and of the
|
https://en.wikipedia.org/wiki/Endoplasmic%20reticulum%20resident%20protein
|
ER retention refers to proteins that are retained in the endoplasmic reticulum, or ER, after folding; these are known as ER resident proteins.
Protein localization to the ER often depends on certain sequences of amino acids located at the N terminus or C terminus. These sequences are known as signal peptides, molecular signatures, or sorting signals.
The classical ER retention signal is the C-terminal KDEL sequence for lumen bound proteins and KKXX (signal sequence is located in cytoplasm) for transmembrane localization. These signals allow for retrieval from the Golgi apparatus by ER retention receptors, effectively maintaining the protein in the ER. Other mechanisms for ER retention are being studied but are not as well characterized as signal retention.
ER retention receptor proteins
KDELR1
KDELR2
KDELR3
See also
KKXX (amino acid sequence)
KDEL (amino acid sequence)
Signal peptide
Protein targeting
References
|
https://en.wikipedia.org/wiki/Urbie%20Green
|
Urban Clifford "Urbie" Green (August 8, 1926 – December 31, 2018) was an American jazz trombonist who toured with Woody Herman, Gene Krupa, Jan Savitt, and Frankie Carle. He played on over 250 recordings and released more than two dozen albums as a soloist. He was inducted into the Alabama Jazz Hall of Fame in 1995.
Early years
Born in Mobile, Alabama, United States, Green was taught the piano as a child by his mother. He learned jazz and popular tunes from the beginning. He started to play trombone, which both older brothers played, when he was about 12. Although he listened to trombonists Tommy Dorsey, J. C. Higginbotham, Jack Jenney, Jack Teagarden and Trummy Young, he has said he was more influenced by the styles of Dizzy Gillespie, Charlie Parker, and Lester Young. His style was also influenced by the vocals of Perry Como and Louis Armstrong. At Auburn High School he was a member of The Auburn Knights Orchestra.
Career
When Green was fifteen years old, his father died, and he began his music career, first with Tommy Reynolds in California, then with Bob Strong, Jan Savitt, and Frankie Carle. In California, he finished high school at the Hollywood Professional School in Los Angeles. In 1947, he joined Gene Krupa's band. Three years later, he and his brother Jack became members of Woody Herman's Thundering Herd.
In 1953, he moved to New York City, and a year later was voted New Star trombonist in the International Critics Poll of Down Beat magazine. During the 1950s a
|
https://en.wikipedia.org/wiki/NGN
|
NGN can refer to :
Neurogenins, a family of bHLH transcription factors involved in specifying neuronal differentiation
Nigerian naira, currency by ISO 4217 code
Noida Greater Noida Expressway, in Delhi, India
Telecommunications
Next Generation Networking, a broad term to describe some key architectural evolutions in telecommunication core and access networks that will be deployed over the next 5–10 years
Non-geographic numbers, in the UK, telephone numbers not assigned to geographic areas or exchanges
Media, publishing, and entertainment
Nippon Golden Network, a Cable television network broadcasting Japanese programs in Hawaii, United States
No Good Nick, an upcoming American comedy web television series.
News Group Newspapers, the umbrella organisation for Rupert Murdoch's news empire.
|
https://en.wikipedia.org/wiki/Repressor
|
In molecular genetics, a repressor is a DNA- or RNA-binding protein that inhibits the expression of one or more genes by binding to the operator or associated silencers. A DNA-binding repressor blocks the attachment of RNA polymerase to the promoter, thus preventing transcription of the genes into messenger RNA. An RNA-binding repressor binds to the mRNA and prevents translation of the mRNA into protein. This blocking or reducing of expression is called repression.
Function
If an inducer, a molecule that initiates the gene expression, is present, then it can interact with the repressor protein and detach it from the operator. RNA polymerase then can transcribe the message (expressing the gene). A co-repressor is a molecule that can bind to the repressor and make it bind to the operator tightly, which decreases transcription.
A repressor that binds with a co-repressor is termed an aporepressor or inactive repressor. One type of aporepressor is the trp repressor, an important metabolic protein in bacteria. The above mechanism of repression is a type of a feedback mechanism because it only allows transcription to occur if a certain condition is present: the presence of specific inducer(s). In contrast, an active repressor binds directly to an operator to repress gene expression.
While repressors are more commonly found in prokaryotes, they are rare in eukaryotes. Furthermore, most known eukaryotic repressors are found in simple organisms (e,g. yeast), and act by interactin
|
https://en.wikipedia.org/wiki/Bone%20morphogenetic%20protein
|
Bone morphogenetic proteins (BMPs) are a group of growth factors also known as cytokines and as metabologens. Originally discovered by their ability to induce the formation of bone and cartilage, BMPs are now considered to constitute a group of pivotal morphogenetic signals, orchestrating tissue architecture throughout the body. The important functioning of BMP signals in physiology is emphasized by the multitude of roles for dysregulated BMP signalling in pathological processes. Cancerous disease often involves misregulation of the BMP signalling system. Absence of BMP signalling is, for instance, an important factor in the progression of colon cancer, and conversely, overactivation of BMP signalling following reflux-induced esophagitis provokes Barrett's esophagus and is thus instrumental in the development of esophageal adenocarcinoma.
Recombinant human BMPs (rhBMPs) are used in orthopedic applications such as spinal fusions, nonunions, and oral surgery. rhBMP-2 and rhBMP-7 are Food and Drug Administration (FDA)-approved for some uses. rhBMP-2 causes more overgrown bone than any other BMPs and is widely used off-label.
Medical uses
BMPs for clinical use are produced using recombinant DNA technology (recombinant human BMPs; rhBMPs). Recombinant BMP-2 and BMP-7 are currently approved for human use.
rhBMPs are used in oral surgeries. BMP-7 has also recently found use in the treatment of chronic kidney disease (CKD). BMP-7 has been shown in murine animal models to reverse t
|
https://en.wikipedia.org/wiki/Classical%20Heisenberg%20model
|
The Classical Heisenberg model, developed by Werner Heisenberg, is the case of the n-vector model, one of the models used in statistical physics to model ferromagnetism, and other phenomena.
Definition
It can be formulated as follows: take a d-dimensional lattice, and a set of spins of the unit length
,
each one placed on a lattice node.
The model is defined through the following Hamiltonian:
with
a coupling between spins.
Properties
The general mathematical formalism used to describe and solve the Heisenberg model and certain generalizations is developed in the article on the Potts model.
In the continuum limit the Heisenberg model (2) gives the following equation of motion
This equation is called the continuous classical Heisenberg ferromagnet equation or shortly Heisenberg model and is integrable in the sense of soliton theory. It admits several integrable and nonintegrable generalizations like Landau-Lifshitz equation, Ishimori equation and so on.
One dimension
In case of long range interaction, , the thermodynamic limit is well defined if ; the magnetization remains zero if ; but the magnetization is positive, at low enough temperature, if (infrared bounds).
As in any 'nearest-neighbor' n-vector model with free boundary conditions, if the external field is zero, there exists a simple exact solution.
Two dimensions
In the case of long-range interaction, , the thermodynamic limit is well defined if ; the magnetization remains zero if ; but the magneti
|
https://en.wikipedia.org/wiki/PGLO
|
The pGLO plasmid is an engineered plasmid used in biotechnology as a vector for creating genetically modified organisms. The plasmid contains several reporter genes, most notably the green fluorescent protein (GFP) and the ampicillin resistance gene. GFP was isolated from the jelly fish Aequorea victoria. Because it shares a bidirectional promoter with a gene for metabolizing arabinose, the GFP gene is expressed in the presence of arabinose, which makes the transgenic organism express its fluorescence under UV light. GFP can be induced in bacteria containing the pGLO plasmid by growing them on +arabinose plates. pGLO is made by Bio-Rad Laboratories.
Structure
pGLO is made up of three genes that are joined together using recombinant DNA technology. They are as follows:
Bla, which codes for the enzyme beta-lactamase giving the transformed bacteria resistance to the beta-lactam family of antibiotics (such as of the penicillin family)
araC, a promoter region that regulates the expression of GFP (specifically, the GFP gene will be expressed only in the presence of arabinose)
GFP, the green fluorescent protein, which gives a green glow if cells produce this type of protein
Like most other circular plasmids, the pGLO plasmid contains an origin of replication (ori), which is a region of the plasmid where replication will originate.
The pGLO plasmid was made famous by researchers in France who used it to produce a green fluorescent rabbit named Alba.
Other features on pGLO, lik
|
https://en.wikipedia.org/wiki/Minnesota%20Wrecking%20Crew%20%28professional%20wrestling%29
|
The Minnesota Wrecking Crew was originally a professional wrestling tag team that was formed by Gene and Lars Anderson but since then has featured a number of wrestlers who wrestled under the Anderson family name despite not being blood related.
History
Gene Anderson formed the original Minnesota Wrecking Crew with Lars Anderson in 1966. They wrestled throughout the country in the late 60s until Lars left to live in Hawaii. In 1969 Gene then brought in Alan Rogowski, and renamed him Ole Anderson. They dominated tag team wrestling in the 1970s, winning the NWA World Tag Team Titles 8 times. Over those years, Lars Anderson was on occasion brought back in as part of this team.
When Gene stopped wrestling in 1981 to manage, the team was disbanded.
In 1985, Ole reformed the Crew with Arn Anderson (his kayfabe nephew) as his partner. They won the NWA National Tag Team Titles and were members of the original Four Horsemen as the Wrecking Crew. They disbanded in 1987 when Ole was kicked out of the Horsemen.
Arn and Ole revived the Wrecking Crew in 1990 but it lasted for only a few months before Ole retired.
Also in 1990, Ole managed the Minnesota Wrecking Crew 2 in NWA while Arn was out injured. This team consisted of Mike Enos and Wayne Bloom. Both members were from Minnesota and wore masks. The two men had previously been AWA World Tag Team Champions, but were beaten by NWA World Tag Team Champions Rick and Scott Steiner in the NWA.
Legacy
In 2001 in Ohio Valley Wrestling, Br
|
https://en.wikipedia.org/wiki/Multiple%20cloning%20site
|
A multiple cloning site (MCS), also called a polylinker, is a short segment of DNA which contains many (up to ~20) restriction sites - a standard feature of engineered plasmids. Restriction sites within an MCS are typically unique, occurring only once within a given plasmid. The purpose of an MCS in a plasmid is to allow a piece of DNA to be inserted into that region.
An MCS is found in a variety of vectors, including cloning vectors to increase the number of copies of target DNA, and in expression vectors to create a protein product. In expression vectors, the MCS is located downstream of the promoter.
Creating a multiple cloning site
In some instances, a vector may not contain an MCS. Rather, an MCS can be added to a vector. The first step is designing complementary oligonucleotide sequences that contain restriction enzyme sites along with additional bases on the end that are complementary to the vector after digesting. Then the oligonucleotide sequences can be annealed and ligated into the digested and purified vector. The digested vector is cut with a restriction enzyme that complements the oligonucleotide insert overhangs. After ligation, transform the vector into bacteria and verify the insert by sequencing. This method can also be used to add new restriction sites to a multiple cloning site.
Uses
Multiple cloning sites are a feature that allows for the insertion of foreign DNA without disrupting the rest of the plasmid which makes it extremely useful in biotechnol
|
https://en.wikipedia.org/wiki/Pyruvate%20dehydrogenase%20lipoamide%20kinase%20isozyme%201
|
Pyruvate dehydrogenase lipoamide kinase isozyme 1, mitochondrial is an enzyme that in humans is encoded by the PDK1 gene. It codes for an isozyme of pyruvate dehydrogenase kinase (PDK).
Pyruvate dehydrogenase (PDH) is a part of a mitochondrial multienzyme complex that catalyzes the oxidative decarboxylation of pyruvate and is one of the major enzymes responsible for the regulation of homeostasis of carbohydrate fuels in mammals. The enzymatic activity is regulated by a phosphorylation/dephosphorylation cycle. Phosphorylation of PDH by a specific pyruvate dehydrogenase kinase (PDK) results in inactivation.
Structure
The mature protein encoded by the PDK4 gene contains 407 amino acids in its sequence. To form the active protein, two of the polypeptide chains come together to form an open conformation. The catalytic domain of PDK1 might exist separately in cells and important for the regulation of the PDK1 substrate. The crystal structural studies suggest that the PIF-pocket is located at the catalytic domain as well.
Function
The Pyruvate Dehydrogenase (PDH) complex must be tightly regulated due to its central role in general metabolism. Within the complex, there are three serine residues on the E1 component that are sites for phosphorylation; this phosphorylation inactivates the complex. In humans, there have been four isozymes of Pyruvate Dehydrogenase Kinase that have been shown to phosphorylate these three sites: PDK1, PDK2, PDK3, and PDK4. PDK1 is the only enzyme capa
|
https://en.wikipedia.org/wiki/Connection
|
Connection may refer to:
Mathematics
Connection (algebraic framework)
Connection (mathematics), a way of specifying a derivative of a geometrical object along a vector field on a manifold
Connection (affine bundle)
Connection (composite bundle)
Connection (fibred manifold)
Connection (principal bundle), gives the derivative of a section of a principal bundle
Connection (vector bundle), differentiates a section of a vector bundle along a vector field
Cartan connection, achieved by identifying tangent spaces with the tangent space of a certain model Klein geometry
Ehresmann connection, gives a manner for differentiating sections of a general fibre bundle
Electrical connection, allows the flow of electrons
Galois connection, a type of correspondence between two partially ordered sets
Affine connection, a geometric object on a smooth manifold which connects nearby tangent spaces
Levi-Civita connection, used in differential geometry and general relativity; differentiates a vector field along another vector field
Music
Connection (The Green Children album), 2013
Connection (Don Ellis album), 1972
Connection (Up10tion album), 2021
Connection (EP), a 2000 split EP by Home Grown and Limbeck
Connection, a 2019 EP by Seyong
"Connection" (Elastica song) (1994)
"Connection" (OneRepublic song) (2018)
"Connection" (Rolling Stones song) (1967)
"Connection", a song by Avail from Satiate
"Connection", a 1976 song by Can from Unlimited Edition
"Connection", a song by the Kooks from 10 Tracks
|
https://en.wikipedia.org/wiki/DigitalBridge
|
DigitalBridge Group, Inc. is a global digital infrastructure investment firm. The company owns, invests in and operates businesses such as cell towers, data centers, fiber, small cells, and edge infrastructure. Headquartered in Boca Raton, DigitalBridge has key offices in Los Angeles, New York, London, and Singapore.
In 2010, DigitalBridge, then still Colony Capital, was reported to manage about $30 billion in investments.
History
Recent investments
In January 2017, Colony NorthStar, Inc. (NYSE: CLNS) was formed through a tri-party merger between Colony Capital, Inc. (NYSE:CLNY), NorthStar Asset Management Group Inc. (NYSE:NSAM) and NorthStar Realty Finance Corp. (NYSE:NRF).
In September 2017, Colony NorthStar agreed to sell its Townsend Group unit to Aon for $475 million.
In October 2017, Colony entered discussions to purchase The Weinstein Company, a movie and TV production studio that sustained damage after its co-founder, Harvey Weinstein, was accused of multiple counts of sexual harassment over three decades. In the wake of the Harvey Weinstein sexual assault scandal, in late October 2017, it was reported that Colony Capital LLC had proved hesitant to purchase Weinstein Co. after a week of exclusive negotiations. Fortress Investment Group was also in talks to provide a loan to Weinstein Co.
In June 2018, The New York Times reported that Colony North Star had raised more than $7 billion in investments since Donald Trump won the 2016 presidential election. 24 percent
|
https://en.wikipedia.org/wiki/Telluride%20%28chemistry%29
|
The telluride ion is the anion Te2− and its derivatives. It is analogous to the other chalcogenide anions, the lighter O2−, S2−, and Se2−, and the heavier Po2−.
In principle, Te2− is formed by the two-e− reduction of tellurium. The redox potential is −1.14 V.
Te(s) + 2 e− ↔ Te2−
Although solutions of the telluride dianion have not been reported, soluble salts of bitelluride (TeH−) are known.
Organic tellurides
Tellurides also describe a class of organotellurium compounds formally derived from Te2−. An illustrative member is dimethyl telluride, which results from the methylation of telluride salts:
2 CH3I + Na2Te → (CH3)2Te + 2 NaI
Dimethyl telluride is formed by the body when tellurium is ingested. Such compounds are often called telluroethers because they are structurally related to ethers with tellurium replacing oxygen, although the length of the C–Te bond is much longer than a C–O bond. C–Te–C angles tend to be closer to 90°.
Inorganic tellurides
Many metal tellurides are known, including some telluride minerals. These include natural gold tellurides, like calaverite and krennerite (AuTe2), and sylvanite (AgAuTe4). They are minor ores of gold, although they comprise the major naturally occurring compounds of gold. (A few other natural compounds of gold, such as the bismuthide maldonite (Au2Bi) and antimonide aurostibite (AuSb2), are known). Although the bonding in such materials is often fairly covalent, they are described casually as salts of Te2−. Using this
|
https://en.wikipedia.org/wiki/John%20Henry%20Comstock
|
John Henry Comstock (February 24, 1849 – March 20, 1931) was an eminent researcher in entomology and arachnology and a leading educator. His work provided the basis for classification of butterflies, moths, and scale insects.
Career
Comstock was born on February 24, 1849, in Janesville, Wisconsin. He entered Cornell University as a student in 1869, a year after the school was founded. He also took classes at Harvard University in the summer of 1872 and at Yale University in 1875.
In 1871, while still a student, Comstock became an assistant to professor Burton Green Wilder. In 1872, in the absence of a professor in entomology, students submitted a petition requesting that Comstock be given permission to deliver a course of lectures upon "Insects Injurious to Vegetation". The lectures were successful, and Comstock was appointed instructor
of entomology in 1873. He received his Bachelor of Science in June 1874, and was made an assistant professor in 1876.
In 1878 Comstock married Anna Botsford. Anna also studied entomology: she earned a degree and worked with her husband to write and illustrate books and articles on the subject. Her beautiful wood engravings illustrate their work. Both became professors of Nature Studies at Cornell. Anna Botsford Comstock was the first female professor at Cornell. Anna wrote an autobiography of the couple, first published in 1953 and edited by Glenn Herrick and Ruby G. Smith, titled The Comstocks of Cornell: John Henry Comstock and Anna Bo
|
https://en.wikipedia.org/wiki/PHLX%20Semiconductor%20Sector
|
The PHLX Semiconductor Sector (SOX) is a Philadelphia Stock Exchange capitalization-weighted index composed of the 30 largest U.S. companies primarily involved in the design, distribution, manufacture, and sale of semiconductors. It was created in 1993 by the Philadelphia Stock Exchange.
The Index contains the following 30 companies as updated on January 20, 2023:
Advanced Micro Devices, Inc., AMD
Analog Devices, Inc., ADI
Applied Materials, Inc., AMAT
ASML Holding N.V., ASML
Azenta, Inc., AZTA
Broadcom Inc., AVGO
Coherent Corp., COHR
Entegris, Inc., ENTG
GLOBALFOUNDRIES Inc., GFS
Intel Corporation, INTC
IPG Photonics Corporation, IPGP
KLA Corporation, KLAC
Lam Research Corporation, LRCX
Lattice Semiconductor Corporation, LSCC
Marvell Technology, Inc., MRVL
Microchip Technology Incorporated, MCHP
Micron Technology, Inc., MU
Monolithic Power Systems, Inc., MPWR
Novanta Inc., NOVT
NVIDIA Corporation, NVDA
NXP Semiconductors N.V., NXPI
ON Semiconductor Corporation, ON
Qorvo, Inc., QRVO
QUALCOMM Incorporated, QCOM
Skyworks Solutions, Inc., SWKS
Synaptics Incorporated, SYNA
Taiwan Semiconductor Manufacturing Company Limited, TSM
Teradyne, Inc., TER
Texas Instruments Incorporated, TXN
Wolfspeed, Inc., WOLF
History
The index was set to an initial value of 200 on December 1, 1993 and was split two-for-one on July 24, 1995; options commenced trading on September 7, 1994.
Semiconductor companies of the United States
External links
https://finance.yah
|
https://en.wikipedia.org/wiki/Lex%20ferenda
|
Lex ferenda is a Latin expression that means "future law" used in the sense of "what the law should be" (as opposed to lex lata - "the current law"). The derivative expression de lege ferenda means "with a view to the future law". The expressions are generally used in the context of proposals for legislative improvements, especially in the academic literature, both in the Anglo-American and in the continental legal systems.
See also
lex lata
de sententia ferenda
List of Latin phrases
Latin legal terminology
de:Latein im Recht#D
|
https://en.wikipedia.org/wiki/Freudenthal%20suspension%20theorem
|
In mathematics, and specifically in the field of homotopy theory, the Freudenthal suspension theorem is the fundamental result leading to the concept of stabilization of homotopy groups and ultimately to stable homotopy theory. It explains the behavior of simultaneously taking suspensions and increasing the index of the homotopy groups of the space in question. It was proved in 1937 by Hans Freudenthal.
The theorem is a corollary of the homotopy excision theorem.
Statement of the theorem
Let X be an n-connected pointed space (a pointed CW-complex or pointed simplicial set). The map
induces a map
on homotopy groups, where Ω denotes the loop functor and Σ denotes the reduced suspension functor. The suspension theorem then states that the induced map on homotopy groups is an isomorphism if k ≤ 2n and an epimorphism if k = 2n + 1.
A basic result on loop spaces gives the relation
so the theorem could otherwise be stated in terms of the map
with the small caveat that in this case one must be careful with the indexing.
Proof
As mentioned above, the Freudenthal suspension theorem follows quickly from homotopy excision; this proof is in terms of the natural map . If a space is -connected, then the pair of spaces is -connected, where is the reduced cone over ; this follows from the relative homotopy long exact sequence. We can decompose as two copies of , say , whose intersection is . Then, homotopy excision says the inclusion map:
induces isomorphisms on and a surj
|
https://en.wikipedia.org/wiki/Torsten%20H%C3%A4gerstrand
|
Torsten Hägerstrand (October 11, 1916, in Moheda – May 3, 2004, in Lund) was a Swedish geographer. He is known for his work on migration, cultural diffusion and time geography.
A native and resident of Sweden, Hägerstrand was a professor (later professor emeritus) of geography at Lund University, where he received his doctorate in 1953. His doctoral research was on cultural diffusion. His research has helped to make Sweden, and particularly Lund, a major center of innovative work in cultural geography. He also influenced the practice of spatial planning in Sweden through his students.
Early life
Hägerstrand's father was a teacher at a remote elementary school and the family lived at the school. Hägerstrand recalled that his early education was based on the pedagogical ideas of Swiss educator Johann Pestalozzi. Several of Hägerstrand's students speculated that his holistic and visionary thinking was rooted in his early education: He was taught local geography, history and folklore at home in the Pestalozzi tradition which was being introduced at that time. Cartography, geology, botany and agronomy were all interrelated parts of a more holistic understanding of processes within a spatial area. To start with, children learned about their immediate environment (e.g., the school room and the farm), then about the village, and gradually the whole district. As a pupil of Hägerstrand, it is easy for me to recognize parts of this tradition which later became what we today would refe
|
https://en.wikipedia.org/wiki/Upper%20motor%20neuron
|
Upper motor neurons (UMNs) is a term introduced by William Gowers in 1886. They are found in the cerebral cortex and brainstem and carry information down to activate interneurons and lower motor neurons, which in turn directly signal muscles to contract or relax. UMNs represent the major origin point for voluntary somatic movement.
Upper motor neurons represent the largest pyramidal cells in the motor regions of the cerebral cortex. The major cell type of the UMNs is the Betz cells residing in layer V of the primary motor cortex, located on the precentral gyrus in the posterior frontal lobe The cell bodies of Betz cell neurons are the largest in the brain, approaching nearly 0.1 mm in diameter. The axons of the upper motor neurons project out of the precentral gyrus travelling through to the brainstem, where they will decussate (intersect) within the lower medulla oblongata to form the lateral corticospinal tract on each side of the spinal cord. The fibers that do not decussate will pass through the medulla and continue on to form the anterior corticospinal tracts.
The upper motor neuron descends in the spinal cord to the level of the appropriate spinal nerve root. At this point, the upper motor neuron synapses with the lower motor neuron or interneurons within the ventral horn of the spinal cord, each of whose axons innervate a fiber of skeletal muscle.
These neurons connect the brain to the appropriate level in the spinal cord, from which point nerve signals cont
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