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https://en.wikipedia.org/wiki/9-j%20symbol
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In physics, Wigner's 9-j symbols were introduced by Eugene Paul Wigner in 1937. They are related to recoupling coefficients in quantum mechanics involving four angular momenta
Recoupling of four angular momentum vectors
Coupling of two angular momenta and is the construction of simultaneous eigenfunctions of and , where , as explained in the article on Clebsch–Gordan coefficients.
Coupling of three angular momenta can be done in several ways, as explained in the article on Racah W-coefficients. Using the notation and techniques of that article, total angular momentum states that arise from coupling the angular momentum vectors , , , and may be written as
Alternatively, one may first couple and to and and to , before coupling and to :
Both sets of functions provide a complete, orthonormal basis for the space with dimension spanned by
Hence, the transformation between the two sets is unitary and the matrix elements of the transformation are given by the scalar products of the functions.
As in the case of the Racah W-coefficients the matrix elements are independent of the total angular momentum projection quantum number ():
Symmetry relations
A 9-j symbol is invariant under reflection about either diagonal as well as even permutations of its rows or columns:
An odd permutation of rows or columns yields a phase factor , where
For example:
Reduction to 6j symbols
The 9-j symbols can be calculated as sums over triple-products of 6-j symbols where the summation extends over all admitted by the triangle conditions in the factors:
.
Special case
When the 9-j symbol is proportional to a 6-j symbol:
Orthogonality relation
The 9-j symbols satisfy this orthogonality relation:
The triangular delta is equal to 1 when the triad (j1, j2, j3) satisfies the triangle conditions, and zero otherwise.
3n-j symbols
The 6-j symbol is the first representative, , of -j symbols that are defined as sums of products of of Wigner's 3-jm coefficients. The sums are ove
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https://en.wikipedia.org/wiki/WoW64
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In computing on Microsoft platforms, WoW64 (Windows 32-bit on Windows 64-bit) is a subsystem of the Windows operating system capable of running 32-bit applications on 64-bit Windows. It is included in all 64-bit versions of Windows—including Windows XP Professional x64 Edition, IA-64 and x64 versions of Windows Server 2003, as well as x64 versions of Windows Vista, Windows Server 2008, Windows 7, Windows 8, Windows Server 2012, Windows 8.1, Windows 10, Windows Server 2016, Windows Server 2019, Windows 11, Windows Server 2022, and Wine. as well as ARM64 versions of Windows 10, Windows 11 and Windows Server 2022, except in Windows Server Server Core where it is an optional component, and Windows Nano Server where it is not included. WoW64 aims to take care of many of the differences between 32-bit Windows and 64-bit Windows, particularly involving structural changes to Windows itself.
Translation libraries
The WoW64 subsystem comprises a lightweight compatibility layer that has similar interfaces on all 64-bit versions of Windows. It aims to create a 32-bit environment that provides the interfaces required to run unmodified 32-bit Windows applications on a 64-bit system. WOW64 is implemented using several DLLs, some of which include:
Wow64.dll, the core interface to the Windows NT kernel that translates (thunks) between 32-bit and 64-bit calls, including pointer and call stack manipulations
Wow64win.dll, which provides the appropriate entry-points for 32-bit applications (win32k thunks)
Wow64cpu.dll, which takes care of switching the processor from 32-bit to 64-bit mode. This is used in x86-64 implementations of Windows only.
Other DLLs and binaries are included for Itanium and ARMv8 64-bit architectures to provide emulation to x86 or for 32-bit entry points if the architecture has a native 32-bit operating mode.
Architectures
Despite its outwardly similar appearance on all versions of 64-bit Windows, WoW64's implementation varies depending on the target instru
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https://en.wikipedia.org/wiki/Rosa%20%C3%97%20centifolia
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Rosa × centifolia (lit. hundred leaved rose; syn. R. gallica var. centifolia (L.) Regel), the Provence rose, cabbage rose or Rose de Mai, is a hybrid rose developed by Dutch breeders in the period between the 17th century and the 19th century, possibly earlier.
History
Its parentage includes Rosa × damascena, but it may be a complex hybrid; its exact hereditary history is not well documented or fully investigated, but it now appears that this is not the "hundred-leaved" (centifolia) rose mentioned by Theophrastus and Pliny: "no unmistakable reference can be traced earlier than about 1580".
The original plant was sterile, but a sport with single flowers appeared in 1769, from which various cultivars known as centifolia roses were developed, many of which are further hybrids. Other cultivars have appeared as further sports from these roses. Rosa × centifolia 'Muscosa' is a sport with a thick covering of resinous hairs on the flower buds, from which most (but not all) "moss roses" are derived. Dwarf or miniature sports have been known for almost as long as the larger forms, including a miniature moss rose 'Moss de Meaux'.
In 1783 the French artist Élisabeth Vigée Le Brun painted a famous portrait of Marie Antoinette holding a pink centifolia rose.
Growth
Individual plants are shrubby in appearance, growing to 1.5–2 m tall, with long drooping canes and greyish green pinnate leaves with 5-7 leaflets. The flowers are round and globular, with numerous thin overlapping petals that are highly scented; they are usually pink, less often white to dark red-purple.
Cultivation and uses
R. × centifolia is particular to the French city of Grasse, known as the perfume capital of the world. It is widely cultivated for its singular fragrance — clear and sweet, with light notes of honey. The flowers are commercially harvested for the production of rose oil, which is commonly used in perfumery.
Centifolia cultivars
Cultivars of Rosa × centifolia that are still grown include:
'Bu
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https://en.wikipedia.org/wiki/RNP%20world
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The RNP world is a hypothesized intermediate period in the origin of life characterized by the existence of ribonucleoproteins. The period followed the hypothesized RNA world and ended with the formation of DNA and contemporary proteins. In the RNP world, RNA molecules began to synthesize peptides. These would eventually become proteins which have since assumed most of the diverse functions RNA performed previously. This transition paved the way for DNA to replace RNA as the primary store of genetic information, leading to life as we know it.
Principle of concept
Thomas Cech, in 2009, proposed the existence of the RNP world after his observation of apparent differences in the composition of catalysts in the two most fundamental processes that maintain and express genetic systems. The maintenance process, DNA replication and transcription, is accomplished purely by protein polymerases. The gene expression process, mRNA splicing and protein synthesis, is catalyzed by RNP complexes (the spliceosome and ribosome).
The difference between how these processes catalyze can be reconciled with the RNA world theory. As an older molecule than DNA, RNA had a hybrid RNA-protein-based maintenance system. Our current DNA world could have resulted from the gradual replacement of RNA catalysis machines with proteins. In this view, ribonucleoproteins and nucleotide-based cofactors are relics of an intermediary era, the RNP world.
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https://en.wikipedia.org/wiki/Oleandrin
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Oleandrin is a cardiac glycoside found in the poisonous plant oleander (Nerium oleander L.). As a main phytochemical of oleander, oleandrin is associated with the toxicity of oleander sap, and has similar properties to digoxin.
Oleander has been used in traditional medicine for its presumed therapeutic purposes, such as for treating cardiac insufficiency. There is no clinical evidence that oleander or its constituents, including oleandrin, are safe or effective. Oleandrin is not approved by regulatory agencies as a prescription drug or dietary supplement.
Structure and reactivity
The structure of oleandrin contains a central steroid nucleus with an unsaturated lactone ring structure on C17 and a dideoxy arabinose group on C3. In addition, the steroid ring has a substitute of an acetyloxy group on C16. The sugar forming the glycoside is L-oleandrose.
Oleandrin resembles very much other glycosides like ouabain and digoxin but has less effect than digoxin. It is however, just like its derivate oleandrigenin, a more potent glycoside than ouabain.
Synthesis
Oleandrin and its derivate oleandrigenin are formed in the N. oleander plant. The oleandrin itself can be won out of the leaves and other parts of the plant but can also be produced in the lab by using cell cultures. Here, the oleandrin synthesis (along with other metabolites) can be stimulated in untransformed plant cell cultures with supplementation of phytohormone. However, this is not enough to produce large quantities because of early cell death. Transgenic cultures of Agrobacteria are able to synthesize great quantities of oleandrin and other metabolites of the oleander plants, fit for pharmaceutical purposes.
Related substances
Oleandrin is, apart from its pure form, also closely related to structural similar glycosides and alkaloids, which all have more or less the same characteristics as oleandrin:
Oleandrigenin is a deglycosylated metabolite of oleandrin. It has however a more mild effect.
Conessi
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https://en.wikipedia.org/wiki/Media%20Dispatch%20Protocol
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The Media Dispatch Protocol (MDP) was developed by the Pro-MPEG Media Dispatch Group to provide an open standard for secure, automated, and tapeless delivery of audio, video and associated data files. Such files typically range from low-resolution content for the web to HDTV and high-resolution digital intermediate files for cinema production.
MDP is essentially a middleware protocol that decouples the technical details of how delivery occurs from the business logic that requires delivery. For example, a TV post-production company might have a contract to deliver a programme to a broadcaster. An MDP agent allows users be able to deal with company and programme names, rather than with filenames and network endpoints. It can also provide a delivery service as part of a service oriented architecture.
MDP acts as a communication layer between business logic and low-level file transfer mechanisms, providing a way to securely communicate and negotiate transfer-specific metadata about file packages, delivery routing, deadlines, and security information, and to manage and coordinate file transfers in progress, whilst hooking all this information to project, company and job identifiers.
MDP works by implementing a 'dispatch transaction' layer by which means agents negotiate and agree the details of the individual file transfers required for the delivery, and control, monitor and report on the progress of the transfers. At the heart of the protocol is the 'Manifest' - an XML document that encapsulates the information about the transaction.
MDP is based on existing open technologies such as XML, HTTP and TLS. The protocol is specified in a layered way to allow the adoption of new technologies (e.g. Web Services protocols such as SOAP and WSDL) as required.
Since early 2005, multiple implementations based on draft versions of the Media Dispatch Protocol have been in use, both for technical testing, and, since April 2005, for real-world production work. The experience with
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https://en.wikipedia.org/wiki/Glycoside-pentoside-hexuronide%3Acation%20symporter%20family
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The Glycoside-Pentoside-Hexuronide (GPH):Cation Symporter Family is part of the major facilitator superfamily and catalyzes uptake of sugars (mostly, but not exclusively, glycosides) in symport with a monovalent cation (H+ or Na+). The various members of the family have been reported to use Na+, H+ or Li, Na+ or Li+, or all three cations as the symported cation.
Structure
Proteins of the GHP family are generally about 500 amino acids in length, although the Gram-positive bacterial lactose permeases are larger, due to a C-terminal hydrophilic domain that is involved in regulation by the phosphotransferase system. All of these proteins possess twelve putative transmembrane α-helical spanners.
Homology
Homologues are from bacteria, including the distantly related sucrose:H+ symporters of plants and a yeast maltose/sucrose:H+ symporter of Schizosaccharomyces pombe. This yeast protein is about 24% identical to the plant sucrose:H+ symporters and is more distantly related to the bacterial members of the GPH family. Limited sequence similarity of some of these proteins with members of the major facilitator superfamily has been observed, and their 3D structures are clearly similar.
Transport Reaction
The generalized transport reaction catalyzed by the GPH:cation symporter family is:
Sugar (out) + [H+ or Na+] (out) → Sugar (in) + [H+ or Na+] (in)
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https://en.wikipedia.org/wiki/Row%20and%20column%20spaces
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In linear algebra, the column space (also called the range or image) of a matrix A is the span (set of all possible linear combinations) of its column vectors. The column space of a matrix is the image or range of the corresponding matrix transformation.
Let be a field. The column space of an matrix with components from is a linear subspace of the m-space . The dimension of the column space is called the rank of the matrix and is at most . A definition for matrices over a ring is also possible.
The row space is defined similarly.
The row space and the column space of a matrix are sometimes denoted as and respectively.
This article considers matrices of real numbers. The row and column spaces are subspaces of the real spaces and respectively.
Overview
Let be an -by- matrix. Then
,
= number of pivots in any echelon form of ,
= the maximum number of linearly independent rows or columns of .
If one considers the matrix as a linear transformation from to , then the column space of the matrix equals the image of this linear transformation.
The column space of a matrix is the set of all linear combinations of the columns in . If , then .
The concept of row space generalizes to matrices over the field of complex numbers, or over any field.
Intuitively, given a matrix , the action of the matrix on a vector will return a linear combination of the columns of weighted by the coordinates of as coefficients. Another way to look at this is that it will (1) first project into the row space of , (2) perform an invertible transformation, and (3) place the resulting vector in the column space of . Thus the result must reside in the column space of . See singular value decomposition for more details on this second interpretation.
Example
Given a matrix :
the rows are
,
,
,
.
Consequently, the row space of is the subspace of spanned by .
Since these four row vectors are linearly independent, the row space is 4-dimensional. Moreover, in this
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https://en.wikipedia.org/wiki/Motty
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Motty (11 July – 21 July 1978) was the only proven hybrid between an Asian and an African elephant. The male calf was born in Chester Zoo, to Asian mother Sheba and African father Jumbolino. He was named after George Mottershead, who founded the Chester Zoo in 1931.
Appearance
Motty's head and ears were morphologically like Loxodonta (African), while the toenail numbers, with five on the front feet and four on the hind were that of Elephas (Asian). The trunk had a single trunk finger as seen in Elephas but the trunk length was more similar to Loxodonta. His vertebral column showed an Loxodonta profile above the shoulders transitioning to the convex hump profile of Elephas below the shoulders.
Cause of death
Due to being born six weeks early, Motty was considered underweight by . Despite intensive human care, Motty died of an umbilical infection 10 days after his birth on 21 July. The necropsy revealed death to be due to necrotizing enterocolitis and E. coli septicaemia present in both his colon and the umbilical cord.
Preservation
His body was preserved by a private company, and is a mounted specimen at the Natural History Museum in London.
Other hybrids
The straight-tusked elephant, an extinct elephant whose closest extant relative is the African forest elephant, interbred with the Asian elephant, as recovered DNA has shown.
Although the Asian elephant Elephas maximus and the African elephant Loxodonta africana belong to different genera, they share the same number of chromosomes, thus making hybridisation possible.
See also
List of individual elephants
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https://en.wikipedia.org/wiki/Qizha
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Qizha (Arabic قزحة qizḥaẗ, pronounced ʼɛzḥa in Palestine) is a black seed paste used in Palestinian cuisine. Made from crushed nigella seeds, the paste has a sharp, bitter taste with slight tones of sweetness. The paste can be used with other condiments, such as tahini, or baked into pies, breads, and pastries.
Production
Qizha is made from the seeds of Nigella sativa of the buttercup family of plants, which is native to the Middle East and India. The seeds, sometimes known as "black cumin", are soaked in salt water for a night, oven roasted, left on rocks to dry in the sun, and finally ground to make a paste.
Some sources consider the cities of Nablus and Jenin to be the source of the best-quality qizha.
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https://en.wikipedia.org/wiki/Cuckoo%20hashing
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Cuckoo hashing is a scheme in computer programming for resolving hash collisions of values of hash functions in a table, with worst-case constant lookup time. The name derives from the behavior of some species of cuckoo, where the cuckoo chick pushes the other eggs or young out of the nest when it hatches in a variation of the behavior referred to as brood parasitism; analogously, inserting a new key into a cuckoo hashing table may push an older key to a different location in the table.
History
Cuckoo hashing was first described by Rasmus Pagh and Flemming Friche Rodler in a 2001 conference paper. The paper was awarded the European Symposium on Algorithms Test-of-Time award in 2020.
Operations
Cuckoo hashing is a form of open addressing in which each non-empty cell of a hash table contains a key or key–value pair. A hash function is used to determine the location for each key, and its presence in the table (or the value associated with it) can be found by examining that cell of the table. However, open addressing suffers from collisions, which happens when more than one key is mapped to the same cell.
The basic idea of cuckoo hashing is to resolve collisions by using two hash functions instead of only one. This provides two possible locations in the hash table for each key. In one of the commonly used variants of the algorithm, the hash table is split into two smaller tables of equal size, and each hash function provides an index into one of these two tables. It is also possible for both hash functions to provide indexes into a single table.
Lookup
Cuckoo hashing uses two hash tables, and . Assuming is the length of each table, the hash functions for the two tables is defined as, and where be the key and be the set whose keys are stored in of or of . The lookup operation is as follows:
The logical or () denotes that, the value of the key is found in either or , which is in worst case.
Deletion
Deletion is performed in since there isn't involvement
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https://en.wikipedia.org/wiki/SourceMeter
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SourceMeter is a source code analyzer tool, which can perform deep static program analysis of the source code of complex programs in C, C++, Java, Python, C#, and RPG (AS/400). FrontEndART has developed SourceMeter based on the Columbus technology researched and developed at the Department of Software Engineering of the University of Szeged.
Background
During the static analysis, an abstract semantic graph (ASG) is constructed from the language elements of the source code. This ASG is then processed by the different tools in the package to calculate product metrics like LLOC, NLE or NOA, identify duplicate code (copy-pasted code; clones), coding rule violations, etc.
SourceMeter can analyze source code conforming to Java 8 and earlier versions, C/C++, RPG III and RPG IV versions (including free-form), C# 6.0 and earlier versions and Python 2.7.8 and earlier versions.
In the case of C/C++, SourceMeter supports the ISO/IEC 14882:2011 international standard extended with several new features from ISO/IEC 14882:2014, and C language defined by the ANSI/ISO 9899:1990, ISO/IEC 9899:1999 and ISO/IEC 9899:2011 standards. Besides the standard features, several GCC and Microsoft specific extensions are also supported.
Features
Precise and deep static analysis, building full semantic graphs, containing semantic edges (calls, references), comments, etc.
60+ source code metrics (complexity, coupling, cohesion, inheritance, etc.), on different levels (package, namespace, class, method, etc.)
Type-2 duplications regarding syntax boundaries
Code duplication metrics (stability, embeddedness, dispersion, etc.)
Detecting inconsistent changes of duplications
Checking coding rules (Differences between PMD rule violations and FaultHunter rule violations)
Detecting security vulnerabilities based on data-flow (SQL injection, XSS, etc.)
Checking metric-based rule violations
Checking Android specific rule violations
Detecting runtime exceptions by means of symbolic code executio
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https://en.wikipedia.org/wiki/Utility%20maximization%20problem
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Utility maximization was first developed by utilitarian philosophers Jeremy Bentham and John Stuart Mill. In microeconomics, the utility maximization problem is the problem consumers face: "How should I spend my money in order to maximize my utility?" It is a type of optimal decision problem. It consists of choosing how much of each available good or service to consume, taking into account a constraint on total spending (income), the prices of the goods and their preferences.
Utility maximization is an important concept in consumer theory as it shows how consumers decide to allocate their income. Because consumers are rational, they seek to extract the most benefit for themselves. However, due to bounded rationality and other biases, consumers sometimes pick bundles that do not necessarily maximize their utility. The utility maximization bundle of the consumer is also not set and can change over time depending on their individual preferences of goods, price changes and increases or decreases in income.
Basic setup
For utility maximization there are four basic steps process to derive consumer demand and find the utility maximizing bundle of the consumer given prices, income, and preferences.
1) Check if Walras's law is satisfied
2) 'Bang for buck'
3) the budget constraint
4) Check for negativity
1) Walras's Law
Walras's law states that if a consumers preferences are complete, monotone and transitive then the optimal demand will lie on the budget line.
Preferences of the consumer
For a utility representation to exist the preferences of the consumer must be complete and transitive (necessary conditions).
Complete
Completeness of preferences indicates that all bundles in the consumption set can be compared by the consumer. For example, if the consumer has 3 bundles A,B and C then;
A B, A C, B A, B C, C B, C A, A A, B B, C C. Therefore, the consumer has complete preferences as they can compare every bundle.
Transitive
Transitivity states that individuals
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https://en.wikipedia.org/wiki/Korringa%E2%80%93Kohn%E2%80%93Rostoker%20method
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The Korringa–Kohn–Rostoker (KKR) method is used to calculate the electronic band structure of periodic solids. In the derivation of the method using multiple scattering theory by Jan Korringa and the derivation based on the Kohn and Rostoker variational method, the muffin-tin approximation was used. Later calculations are done with full potentials having no shape restrictions.
Introduction
All solids in their ideal state are single crystals with the atoms arranged on a periodic lattice. In condensed matter physics, the properties of such solids are explained on the basis of their electronic structure. This requires the solution of a complicated many-electron problem, but the density functional theory of Walter Kohn makes it possible to reduce it to the solution of a Schroedinger equation with a one-electron periodic potential. The problem is further simplified with the use of group theory and in particular Bloch's theorem, which leads to the result that the energy eigenvalues depend on the crystal momentum and are divided into bands. Band theory is used to calculate the eigenvalues and wave functions.
As compared with other band structure methods, the Korringa-Kohn-Rostoker (KKR) band structure method has the advantage of dealing with small matrices due to the fast convergence of scattering operators in angular momentum space, and disordered systems where it allows to carry out with relative ease the ensemble configuration averages. The KKR method does have a few “bills” to pay, e.g., (1) the calculation of KKR structure constants, the empty lattice propagators, must be carried out by the Ewald’s sums for each energy and k-point, and (2) the KKR functions have a pole structure on the real energy axis, which requires a much larger number of k points for the Brillouin Zone (BZ) integration as compared with other band theory methods. The KKR method has been implemented in several codes for electronic structure and spectroscopy calculations, such as MuST, AkaiKKR, sp
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https://en.wikipedia.org/wiki/Spongin
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Spongin, a modified type of collagen protein, forms the fibrous skeleton of most organisms among the phylum Porifera, the sponges. It is secreted by sponge cells known as spongocytes.
Spongin gives a sponge its flexibility. True spongin is found only in members of the class Demospongiae.
Research directions
Use in the removal of phenolic compounds from wastewater
Researchers have found spongin to be useful in the photocatalytic degradation and removal of bisphenols (such as BPA) in wastewater. A heterogeneous catalyst consisting of a spongin scaffold for iron phthalocyanine (SFe) in conjunction with peroxide and UV radiation has been shown to remove phenolic wastes more quickly and efficiently than conventional methods. Other research using spongin scaffolds for the immobilization of Trametes versicolor Laccase has shown similar results in phenol degradation.
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https://en.wikipedia.org/wiki/Media%20Delivery%20Index
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The Media Delivery Index (MDI) is a set of measures that can be used to monitor both the quality of a delivered video stream as well as to show system margin for IPTV systems by providing an accurate measurement of jitter and delay at network level (Internet Protocol, IP), which are the main causes for quality loss. Identifying and quantizing such problems in this kind of networks is key to maintaining high quality video delivery and providing indications that warn system operators with enough advance notice to allow corrective action.
The Media Delivery Index is typically displayed as two numbers separated by a colon: the Delay Factor (DF) and the Media Loss Rate (MLR).
Context
The Media Delivery Index (MDI) may be able to identify problems caused by:
Time distortion
If packets are delayed by the network, some packets arrive in bursts with interpacket delays shorter than when they were transmitted, while others are delayed such that they arrive with greater delay between packets than when they were transmitted from the source (see figure below). This time difference between when a packet actually arrives and the expected arrival time is defined as packet jitter or time distortion.
A receiver displaying the video at its nominal rate must accommodate the varying input stream arrival times by buffering the data arriving early and assuring that there is enough already stored data to face the possible delays in the received data (because of this the buffer is filled before displaying).
Similarly, the network infrastructure (switches, routers,…) uses buffers at each node to avoid packet loss. These buffers must be sized appropriately to handle network congestion.
Packet delays can be caused by multiple facts, among which there are the way traffic is routed through the infrastructure and possible differences between link speeds in the infrastructure.
Moreover, some methods for delivering Quality of Service (QOS) using packet metering algorithms may intentionally h
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https://en.wikipedia.org/wiki/Nature%20Electronics
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Nature Electronics is a monthly peer-reviewed scientific journal published by Nature Portfolio. It was established in 2018. The editor-in-chief is Owain Vaughan.
Abstracting and indexing
The journal is abstracted and indexed in:
Science Citation Index Expanded
Scopus
According to the Journal Citation Reports, the journal has a 2021 impact factor of 33.255, ranking it 1st out of 276 journals in the category "Engineering, Electrical & Electronic".
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https://en.wikipedia.org/wiki/Steam
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Steam is a substance containing water in the gas phase, and sometimes also an aerosol of liquid water droplets, or air. This may occur due to evaporation or due to boiling, where heat is applied until water reaches the enthalpy of vaporization. Steam that is saturated or superheated (water vapor) is invisible; however, wet steam, a visible mist or aerosol of water droplets, is often referred to as "steam".
Water increases in volume by 1,700 times at standard temperature and pressure; this change in volume can be converted into mechanical work by steam engines such as reciprocating piston type engines and steam turbines, which are a sub-group of steam engines. Piston type steam engines played a central role in the Industrial Revolution and modern steam turbines are used to generate more than 80% of the world's electricity. If liquid water comes in contact with a very hot surface or depressurizes quickly below its vapor pressure, it can create a steam explosion.
Types of steam and conversions
Steam is traditionally created by heating a boiler via burning coal and other fuels, but it is also possible to create steam with solar energy. Water vapor that includes water droplets is described as wet steam. As wet steam is heated further, the droplets evaporate, and at a high enough temperature (which depends on the pressure) all of the water evaporates and the system is in vapor–liquid equilibrium. When steam has reached this equilibrium point, it is referred to as saturated steam.
Superheated steam or live steam is steam at a temperature higher than its boiling point for the pressure, which only occurs when all liquid water has evaporated or has been removed from the system.
Steam tables contain thermodynamic data for water/saturated steam and are often used by engineers and scientists in design and operation of equipment where thermodynamic cycles involving steam are used. Additionally, thermodynamic phase diagrams for water/steam, such as a temperature-entropy dia
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https://en.wikipedia.org/wiki/Planking%20%28fad%29
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Planking (or the Lying Down Game) is an activity consisting of lying in a face down position, sometimes in an unusual or incongruous location. The palms of the hands are typically touching the sides of the body and the toes are typically touching the ground. Some players compete to find the most unusual and original location in which to play. The term planking refers to mimicking a wooden plank. Planking can include lying flat on a flat surface, or holding the body flat while it is supported in only some regions, with other parts of the body suspended. Many participants in planking have photographed the activity in unusual locations and have shared such pictures through social media.
Planking gained popularity rapidly and eventually notoriety from early-mid 2011 before slowly phasing out in early 2012.
History
A planking-like activity, called face dancing by its participants, was initiated in 1984 in Edmonds, Washington in the US by Scott Amy and Joel Marshall. The two high school age boys were walking in a park when they came upon a baseball game. They decided to lie face down in right field to see if anyone would react.
The first video-recorded occurrence of planking was in 1994 when Tom Green performed a stunt he called "Dead Guy" for a cable TV show, which consisted of Green lying down on an Ottawa sidewalk without moving. Green, who was in an MTV show in the 1990s, is a comedian known for his pranks. He informed CNN about this video evidence and how it did not air on the show, stating that it was "a very obscure piece of video." Green tweeted "Just found video of me #planking in 1994. I will post it soon. Let people know. :)" on July 12, 2011.
However, the video sketch was never aired. So when, in 1997, two bored school boys in Taunton, England, started lying face-down in public places to amuse themselves and baffle onlookers, they could not have known of Green's stunt. Gary Clarkson (then aged 15) and Christian Langdon (then aged 12) called it the "lyi
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https://en.wikipedia.org/wiki/Elastic%20cartilage
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Elastic cartilage, fibroelastic cartilage or yellow fibrocartilage is a type of cartilage present in the pinnae (auricles) of the ear giving it shape, provides shape for the lateral region of the external auditory meatus, medial part of the auditory canal Eustachian tube, corniculate and cuneiform laryneal cartilages, and the epiglottis. It contains elastic fiber networks and collagen type II fibers. The principal protein is elastin.
Structure
Elastic cartilage is histologically similar to hyaline cartilage but contains many yellow elastic fibers lying in a solid matrix. These fibers form bundles that appear dark under a microscope. The elastic fibers require special staining since when it is stained using haematoxylin and eosin (H&E) stain it appears the same as hyaline cartilage. Verhoeff van Geison stains are used (giving the elastic fibers a black color), but aldehyde fuchsin stains, Weigert's elastic stains, and orcein stains also work. These fibers give elastic cartilage great flexibility so that it is able to withstand repeated bending. Similarly to hyaline one or multiple chondrocytes lie between the spaces (or lacunea) in the fibres. The chondrocytes only make up 2% of the tissue's volume. Chondrocytes and the extracellular matrix are contained in an outerlayer named the perichondrium (which is a layer of dense irregular connective tissue that surrounds cartilage which is independent of the joint). It is found in the epiglottis (part of the larynx), and the pinnae (the external ear flaps of many mammals). Elastin fibers stain dark purple/black with Verhoeff's stain.
The extracellular matrix contains Elastin, fibrillin, glycoproteins, collagen types II, IX, X, and XI, and the proteoglycan aggrecan. the components within the extracellular matrix are produced by the chondroblasts located within the edges of the perichondrium.
Elastic fibers within the extracellular matrix are made up of elastin proteins which co-polymerize with fibrillin forming fiber-li
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https://en.wikipedia.org/wiki/Continuity%20set
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In measure theory, a branch of mathematics, a continuity set of a measure μ is any Borel set B such that
where is the (topological) boundary of B. For signed measures, one asks that
The class of all continuity sets for given measure μ forms a ring.
Similarly, for a random variable X, a set B is called continuity set if
Continuity set of a function
The continuity set C(f) of a function f is the set of points where f is continuous.
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https://en.wikipedia.org/wiki/ISO/IEC%207064
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ISO/IEC 7064 is a standard promulgated by the International Standards Organization (ISO) and International Electrotechnical Commission (IEC) that defines algorithms for calculating check digit characters. The checks should be applicable to alphanumeric strings and should be able to detect all single substitution errors, all or nearly all single local transposition errors, all or nearly all circular shift errors, a high proportion of double substitution errors, a high proportion of all other errors.
Standards
Status: Published - ISO/IEC 7064:2003 Information technology -- Security techniques -- Check character systems
Status: Withdrawn - ISO 7064:1983 Data processing -- Check character systems
Usage
It is referred to by other ISO standards:
International Bank Account Number (IBAN)
International Standard Text Code (ISTC)
International Standard Name Identifier (ISNI)
Legal Entity Identifier (LEI)
and by other systems:
Personal identification number (Croatia)
Resident Identity Card (People's Republic of China)
Global Release Identifier
ORCID
External links
Official ISO 7064:2003 Standard Documentation International Organization for Standardization (ISO)
Error detection and correction
07064
Checksum algorithms
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https://en.wikipedia.org/wiki/Litter%20%28zoology%29
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A litter is the live birth of multiple offspring at one time in animals from the same mother and usually from one set of parents, particularly from three to eight offspring. The word is most often used for the offspring of mammals, but can be used for any animal that gives birth to multiple young. In comparison, a group of eggs and the offspring that hatch from them are frequently called a clutch, while young birds are often called a brood. Animals from the same litter are referred to as litter-mates.
Litter
A species' average litter size is generally equal to one half of the number of teats and the maximum litter size generally matches the number of teats. Not all species abide by this rule, however. The naked mole rat, for example, averages roughly eleven young per birth and has eleven teats.
Animals frequently display grouping behavior in herds, swarms, flocks, or colonies, and these multiple births derive similar advantages. A litter offers some protection from predation, not particularly to the individual young but to the parents' investment in breeding. With multiple young, predators could eat several and others could still survive to reach maturity, but with only one offspring, its loss could mean a wasted breeding season. The other significant advantage is the chance for the healthiest young animals to be favored from a group. Rather than it being a conscious decision on the part of the parents, the fittest and strongest baby competes most successfully for food and space, leaving the weakest young, or runts, to die through lack of care.
In the wild, only a small percentage, if any, of the litter may survive to maturity, whereas for domesticated animals and those in captivity with human care the whole litter almost always survives. Kittens and puppies are in this group. Carnivorans, rodents, and pigs usually have litters, while primates and larger herbivores usually have singletons.
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https://en.wikipedia.org/wiki/List%20of%20random%20number%20generators
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Random number generators are important in many kinds of technical applications, including physics, engineering or mathematical computer studies (e.g., Monte Carlo simulations), cryptography and gambling (on game servers).
This list includes many common types, regardless of quality or applicability to a given use case.
Pseudorandom number generators (PRNGs)
The following algorithms are pseudorandom number generators.
Cryptographic algorithms
Cipher algorithms and cryptographic hashes can be used as very high-quality pseudorandom number generators. However, generally they are considerably slower (typically by a factor 2–10) than fast, non-cryptographic random number generators.
These include:
Stream ciphers. Popular choices are Salsa20 or ChaCha (often with the number of rounds reduced to 8 for speed), ISAAC, HC-128 and RC4.
Block ciphers in counter mode. Common choices are AES (which is very fast on systems supporting it in hardware), TwoFish, Serpent and Camellia.
Cryptographic hash functions
A few cryptographically secure pseudorandom number generators do not rely on cipher algorithms but try to link mathematically the difficulty of distinguishing their output from a `true' random stream to a computationally difficult problem. These approaches are theoretically important but are too slow to be practical in most applications. They include:
Blum–Micali algorithm (1984)
Blum Blum Shub (1986)
Naor–Reingold pseudorandom function (1997)
Random number generators that use external entropy
These approaches combine a pseudo-random number generator (often in the form of a block or stream cipher) with an external source of randomness (e.g., mouse movements, delay between keyboard presses etc.).
/dev/random – Unix-like systems
CryptGenRandom – Microsoft Windows
Fortuna
RDRAND instructions (called Intel Secure Key by Intel), available in Intel x86 CPUs since 2012. They use the AES generator built into the CPU, reseeding it periodically.
True Random Number Gen
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https://en.wikipedia.org/wiki/Bone%20resorption
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Bone resorption is resorption of bone tissue, that is, the process by which osteoclasts break down the tissue in bones and release the minerals, resulting in a transfer of calcium from bone tissue to the blood.
The osteoclasts are multi-nucleated cells that contain numerous mitochondria and lysosomes. These are the cells responsible for the resorption of bone. Osteoblasts are generally present on the outer layer of bone, just beneath the periosteum. Attachment of the osteoclast to the osteon begins the process. The osteoclast then induces an infolding of its cell membrane and secretes collagenase and other enzymes important in the resorption process. High levels of calcium, magnesium, phosphate and products of collagen will be released into the extracellular fluid as the osteoclasts tunnel into the mineralized bone. Osteoclasts are prominent in the tissue destruction found in psoriatic arthritis and rheumatological disorders.
The human body is in a constant state of bone remodeling. Bone remodeling is a process which maintains bone strength and ion homeostasis by replacing discrete parts of old bone with newly synthesized packets of proteinaceous matrix. Bone is resorbed by osteoclasts, and is deposited by osteoblasts in a process called ossification. Osteocyte activity plays a key role in this process. Conditions that result in a decrease in bone mass can either be caused by an increase in resorption or by a decrease in ossification. During childhood, bone formation exceeds resorption. As the aging process occurs, resorption exceeds formation.
Bone resorption rates are much higher in post-menopausal older women due to estrogen deficiency related with menopause. Common treatments include drugs that increase bone mineral density. Bisphosphonates, RANKL inhibitors, SERMs—selective oestrogen receptor modulators, hormone replacement therapy and calcitonin are some of the common treatments. Light weight bearing exercise tends to eliminate the negative effects of bon
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https://en.wikipedia.org/wiki/Inferior%20pharyngeal%20constrictor%20muscle
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The inferior pharyngeal constrictor muscle is a skeletal muscle of the neck. It is the thickest of the three outer pharyngeal muscles. It arises from the sides of the cricoid cartilage and the thyroid cartilage. It is supplied by the vagus nerve (CN X). It is active during swallowing, and partially during breathing and speech. It may be affected by Zenker's diverticulum.
Structure
The inferior pharyngeal constrictor muscle is composed of two parts. The first part (and more superior) arises from the thyroid cartilage (thyropharyngeal part), and the second part arises from the cricoid cartilage (cricopharyngeal part).
On the thyroid cartilage, it arises from the oblique line on the side of the lamina, from the surface behind this nearly as far as the posterior border and from the inferior horn of the thyroid cartilage.
From the cricoid cartilage, it arises in the interval between the cricothyroid muscle in front, and the articular facet for the inferior horn of the thyroid cartilage behind.
From these origins, the fibers spread backward and medially to insert with the muscle of the opposite side into the fibrous pharyngeal raphe in the posterior median line of the pharynx. The thyropharyngeal part mainly uses type 2 fibres (anaerobic), while the cricopharyngeal part mainly uses type 1 fibres (aerobic). Fibre type may change after birth.
The inferior fibers are horizontal and continuous with the circular fibers of the esophagus; the rest ascend, increasing in obliquity, and overlap the middle pharyngeal constrictor muscle. The cricopharyngeal part is synonymous with the upper esophageal sphincter (UES), which controls the opening of the cervical esophagus. It is sometimes referred to as the cricopharyngeal inlet.
Nerve supply
The inferior pharyngeal constrictor muscle can be supplied by branches from the pharyngeal plexus, the recurrent laryngeal nerve, the external branch of the superior laryngeal nerve, or a combination of these (the recurrent laryngeal nerv
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https://en.wikipedia.org/wiki/Chromatics%20Inc.
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Chromatics Inc. was a color graphics display manufacturer based in Tucker, Georgia. Their systems predated the personal computer era of inexpensive graphics displays, and were typically used as peripheral devices, connected to a mainframe or minicomputer. In some configurations, a Chromatics graphics terminal could be used as a stand-alone workstation, with disk drives and an operating system.
Chromatics pursued the higher performance end of the graphics marketplace, including such applications as flight simulation and air traffic control. They sold many systems into military and government contracts. Several configurations received Tempest certification. Others were ruggedized to withstand shock and vibration.
History
The company was founded in 1976 by Terry Hughey, who left Intelligent Systems Corporation (another manufacturer of graphics terminals) to focus on higher-end systems. Other principals included Dave Scott (Vice President of Digital Engineering) and Roger Moonen (Vice President of Analog Engineering). Chromatics was acquired by Barco NV in 1990, with Scott becoming president of U.S. operations for Barco.
Products
CG Series
The CG series included a graphics display, processor, and memory. In its most basic configuration, it would be connected via an RS-232 serial port to a larger computer. Programs running on that "host" machine would generate commands in Chromatics' proprietary graphics language, and transmit them to the CG. Such commands would cause the CG to draw primitive shapes (lines, circles, rectangles, etc.) in various colors, which could be combined to form more complex images. A typical command to draw a circle would be: <02> C 256,256,100, where the single ASCII character <02> (or STX) represents the Plot command, C indicates a circle, and the three numbers represent the circle's X-Y position and radius.
A CG system could also include 8" floppy diskette drives, a disk operating system for storing graphics images, and a version of Microso
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https://en.wikipedia.org/wiki/Seedling
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A seedling is a young sporophyte developing out of a plant embryo from a seed. Seedling development starts with germination of the seed. A typical young seedling consists of three main parts: the radicle (embryonic root), the hypocotyl (embryonic shoot), and the cotyledons (seed leaves). The two classes of flowering plants (angiosperms) are distinguished by their numbers of seed leaves: monocotyledons (monocots) have one blade-shaped cotyledon, whereas dicotyledons (dicots) possess two round cotyledons. Gymnosperms are more varied. For example, pine seedlings have up to eight cotyledons. The seedlings of some flowering plants have no cotyledons at all. These are said to be acotyledons.
The plumule is the part of a seed embryo that develops into the shoot bearing the first true leaves of a plant. In most seeds, for example the sunflower, the plumule is a small conical structure without any leaf structure. Growth of the plumule does not occur until the cotyledons have grown above ground. This is epigeal germination. However, in seeds such as the broad bean, a leaf structure is visible on the plumule in the seed. These seeds develop by the plumule growing up through the soil with the cotyledons remaining below the surface. This is known as hypogeal germination.
Photomorphogenesis and etiolation
Dicot seedlings grown in the light develop short hypocotyls and open cotyledons exposing the epicotyl. This is also referred to as photomorphogenesis. In contrast, seedlings grown in the dark develop long hypocotyls and their cotyledons remain closed around the epicotyl in an apical hook. This is referred to as skotomorphogenesis or etiolation. Etiolated seedlings are yellowish in color as chlorophyll synthesis and chloroplast development depend on light. They will open their cotyledons and turn green when treated with light.
In a natural situation, seedling development starts with skotomorphogenesis while the seedling is growing through the soil and attempting to reach the
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https://en.wikipedia.org/wiki/GGDEF%20domain
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In molecular biology, the GGDEF domain is a protein domain which appears to be ubiquitous in bacteria and is often linked to a regulatory domain, such as a phosphorylation receiver or oxygen sensing domain. Its function is to act as a diguanylate cyclase and synthesize cyclic di-GMP, which is used as an intracellular signalling molecule in a wide variety of bacteria. Enzymatic activity can be strongly influenced by the adjacent domains. Processes regulated by this domain include exopolysaccharide synthesis, biofilm formation, motility and cell differentiation.
Structural studies of PleD from Caulobacter crescentus show that this domain forms a five-stranded beta sheet surrounded by helices, similar to the catalytic core of adenylate cyclase.
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https://en.wikipedia.org/wiki/Physiome
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The physiome of an individual's or species' physiological state is the description of its functional behavior. The physiome describes the physiological dynamics of the normal intact organism and is built upon information and
structure (genome, proteome, and morphome). The term comes from "physio-" (nature) and "-ome" (as a whole).
The concept of a physiome project was presented to the International Union of Physiological Sciences (IUPS) by its Commission on Bioengineering in Physiology in 1993. A workshop on designing the Physiome Project was held in 1997. At its world congress in 2001, the IUPS designated the project as a major focus for the next decade. The project is led by the Physiome Commission of the IUPS.
Other research initiatives related to the physiome include:
The EuroPhysiome Initiative
The NSR Physiome Project of the National Simulation Resource (NSR) at the University of Washington, supporting the IUPS Physiome Project
The Wellcome Trust Heart Physiome Project, a collaboration between the University of Auckland and the University of Oxford, part of the wider IUPS Physiome Project
See also
Physiomics
Living Human Project
Virtual Physiological Human
Virtual Physiological Rat
Cytome
Human Genome Project
List of omics topics in biology
Cardiophysics
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https://en.wikipedia.org/wiki/Unary%20operation
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In mathematics, a unary operation is an operation with only one operand, i.e. a single input. This is in contrast to binary operations, which use two operands. An example is any function , where is a set. The function is a unary operation on .
Common notations are prefix notation (e.g. ¬, −), postfix notation (e.g. factorial ), functional notation (e.g. or ), and superscripts (e.g. transpose ). Other notations exist as well, for example, in the case of the square root, a horizontal bar extending the square root sign over the argument can indicate the extent of the argument.
Examples
Absolute value
Obtaining the absolute value of a number is a unary operation. This function is defined as where is the absolute value of .
Negation
This is used to find the negative value of a single number. This is technically not a unary operation as is just short form of . Here are some examples:
Unary negative and positive
As unary operations have only one operand they are evaluated before other operations containing them. Here is an example using negation:
Here, the first '−' represents the binary subtraction operation, while the second '−' represents the unary negation of the 2 (or '−2' could be taken to mean the integer −2). Therefore, the expression is equal to:
Technically, there is also a unary + operation but it is not needed since we assume an unsigned value to be positive:
The unary + operation does not change the sign of a negative operation:
In this case, a unary negation is needed to change the sign:
Trigonometry
In trigonometry, the trigonometric functions, such as , , and , can be seen as unary operations. This is because it is possible to provide only one term as input for these functions and retrieve a result. By contrast, binary operations, such as addition, require two different terms to compute a result.
Examples from programming languages
JavaScript
In JavaScript, these operators are unary:
Increment: ++x, x++
Decrement: --x, x--
Positive: +x
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https://en.wikipedia.org/wiki/Huntington%27s%20Disease%20Society%20of%20America
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The Huntington's Disease Society of America is a US non-profit organization dedicated to improving the lives of those affected by Huntington's disease, an incurable, genetically transmitted degenerative disease of the nervous system that affects movement, thinking, and some aspects of personality.
The Huntington's Disease Society of America is the largest non-profit volunteer organization dedicated to improving the lives of everyone affected by Huntington's Disease. Founded in 1967 by Marjorie Guthrie, wife of folk legend Woody Guthrie who died of HD, the Society works to provide the family services, education, advocacy and research for the more than 41,000 people diagnosed with HD in the United States.
HDSA supports and participates in the HD Drug Research Pipeline, which develops potential therapies to treat and eventually cure HD; and HDSA also supports 50+ HDSA Centers of Excellence at major medical facilities throughout the U.S., where people with HD and their families receive comprehensive medical, psychological and social services, in addition to physical and occupational therapy and genetic testing and counseling. The Society comprises 50+ volunteer-led local chapters and affiliates across the country with its headquarters in New York City. Additionally, HDSA hosts more than 200 support groups for people with HD, their families, caregivers and people at-risk, and is a resource on Huntington's Disease for medical professionals and the general public.
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https://en.wikipedia.org/wiki/Method%20of%20moving%20asymptotes
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The Method of Moving Asymptotes (MMA) is an optimization algorithm developed by Krister Svanberg in the 1980s. It's primarily used for solving non-linear programming problems, particularly those related to structural design and topology optimization.
History
MMA was introduced by Krister Svanberg in a 1987 paper titled, "The method of moving asymptotes—a new method for structural optimization." The method was proposed as an alternative to traditional optimization methods, offering an approach that could handle large-scale problems, especially in the realm of structural design. Another paper was published in 1993 by Scanberg which added some extensions to the method, including mini-max formulations and first and second order dual methods to solve subproblems. Another version that is globally convergent was proposed by Zillober.
Algorithm overview
The Method of Moving Asymptotes functions as an iterative scheme. The key idea behind MMA is to approximate the original non-linear constraints and objective function with a simpler, convex approximation. This approximation is represented by linear constraints and a convex objective function.
Starting from an initial guess, each iteration consists of the following steps:
Step I
Given an iteration point , calculate and the gradients for .
Step II
Generate a subproblem by replacing, in , the (usually implicit) functions by approximating explicit functions , based on the calculations from Step I.
Step III
Solve and let the optimal solution of this subproblem be the next iteration point . Let and return to Step I until convergence.
The moving asymptotes serve as an adaptive mechanism. They shift and change with each iteration, progressively closing in on the optimal solution. This ensures that the approximations become increasingly accurate as the algorithm progresses.
Applications
The Method of Moving Asymptotes has been widely applied in various fields including:
Structural optimization: Design of truss s
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https://en.wikipedia.org/wiki/Lecanorine%20lichen
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A lichen has lecanorine fruiting body parts if they are shaped like a plate with a ring around them, and that ring is made of tissue similar to the main non-fruiting body part of the lichen. The name comes from the name of the lichen genus Lecanora, whose members have such apothecia. If a lichen has lecanorine apothecia, the lichen itself is sometimes described as being lecanorine.
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https://en.wikipedia.org/wiki/Graph%20sandwich%20problem
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In graph theory and computer science, the graph sandwich problem is a problem of finding a graph that belongs to a particular family of graphs and is "sandwiched" between two other graphs, one of which must be a subgraph and the other of which must be a supergraph of the desired graph.
Graph sandwich problems generalize the problem of testing whether a given graph belongs to a family of graphs, and have attracted attention because of their
applications and as a natural generalization of recognition problems.
Problem statement
More precisely, given a vertex set V, a mandatory edge set E1,
and a larger edge set E2,
a graph G = (V, E) is called a sandwich graph for the pair
G1 = (V, E1), G2 = (V, E2) if
E1 ⊆ E ⊆ E2.
The graph sandwich problem for property Π is defined as follows:
Graph Sandwich Problem for Property Π:
Instance: Vertex set V and edge sets E1 ⊆ E2 ⊆ V × V.
Question: Is there a graph G = (V, E) such that E1 ⊆ E ⊆ E2 and G satisfies property Π ?
The recognition problem for a class of graphs (those satisfying a property Π)
is equivalent to the particular graph sandwich problem where
E1 = E2, that is, the optional edge set is empty.
Computational complexity
The graph sandwich problem is NP-complete when Π is the property of being a chordal graph, comparability graph, permutation graph, chordal bipartite graph, or chain graph. It can be solved in polynomial time for split graphs, threshold graphs, and graphs in which every five vertices contain at most one four-vertex induced path.
The complexity status has also been settled for the H-free graph sandwich problems
for each of the four-vertex graphs H.
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https://en.wikipedia.org/wiki/Cellular%20thermal%20shift%20assay
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CEllular Thermal Shift Assay (CETSA®) is a patented label free chemoproteomics method that has enabled measurements of compound target engagement in intact cells and tissue, without modifications to the target protein. This is accomplished by comparing the measured cellular thermal stability of the protein in the presence and absence of the test compound. An efficacious compound binding to its intended target will affect associated proteins and thereby leave traces in the cell in form of changed signalling patterns. Such patterns can arise from for example loss or gain of protein-protein interactions, phosphorylations or release of regulatory molecules.
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https://en.wikipedia.org/wiki/John%20Milnor
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John Willard Milnor (born February 20, 1931) is an American mathematician known for his work in differential topology, algebraic K-theory and low-dimensional holomorphic dynamical systems. Milnor is a distinguished professor at Stony Brook University and one of the five mathematicians to have won the Fields Medal, the Wolf Prize, and the Abel Prize (the others being Serre, Thompson, Deligne, and Margulis).
Early life and career
Milnor was born on February 20, 1931, in Orange, New Jersey. His father was J. Willard Milnor, an engineer, and his mother was Emily Cox Milnor. As an undergraduate at Princeton University he was named a Putnam Fellow in 1949 and 1950 and also proved the Fáry–Milnor theorem when he was only 19 years old. Milnor graduated with an A.B. in mathematics in 1951 after completing a senior thesis, titled "Link groups", under the supervision of Robert H. Fox. He remained at Princeton to pursue graduate studies and received his Ph.D. in mathematics in 1954 after completing a doctoral dissertation, titled "Isotopy of links", also under the supervision of Fox. His dissertation concerned link groups (a generalization of the classical knot group) and their associated link structure, classifying Brunnian links up to link-homotopy and introduced new invariants of it, called Milnor invariants. Upon completing his doctorate, he went on to work at Princeton. He was a professor at the Institute for Advanced Study from 1970 to 1990.
He was an editor of the Annals of Mathematics for a number of years after 1962. He has written a number of books which are famous for their clarity, presentation, and an inspiration for the research by many mathematicians in their areas even after many decades since their publication. He served as Vice President of the AMS in 1976–77 period.
His students have included Tadatoshi Akiba, Jon Folkman, John Mather, Laurent C. Siebenmann, Michael Spivak, and Jonathan Sondow. His wife, Dusa McDuff, is a professor of mathematics at Barnar
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https://en.wikipedia.org/wiki/Petrosquamous%20suture
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The petrosquamous suture is a cranial suture between the petrous portion and the squama of the temporal bone. It forms the Koerner's septum. The petrous portion forms the medial component of the osseous margin, while the squama forms the lateral component. The anterolateral portion (squama) arises from the mesenchyme at 8 weeks of embryogenesis while the petromastoid portion develops later from a cartilaginous center at 6 months of fetal development.
In certain people, it can contain an emissary vein, referred to as the petrosquamosal sinus. Being aware of this anatomic variant with preoperative CT scanning can be important to prevent bleeding in certain types of otolaryngological surgeries. Some authors have theorized that a persistent venous sinus reflects an arrest in embryologic development.
See also
Petrotympanic fissure
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https://en.wikipedia.org/wiki/LINDO
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LINDO (Linear, Interactive, and Discrete Optimizer) is a software package for linear programming, integer programming, nonlinear programming, stochastic programming and global optimization.
Today, LINDO solvers are part of LINDO API (Application Programming Interface) a set of software libraries that can be called from different programming languages to create custom mathematical optimization applications.
It is designed to solve optimization problems that arise in areas of business, industry, research, and government. The LINDO package includes sample applications related to product distribution, ingredient blending, production, personnel scheduling, inventory management.
LINDO also creates "What'sBest!" which is an add-in for linear, integer and nonlinear optimization. First released for Lotus 1-2-3 and later also for Microsoft Excel.
Features
LINDO provides routines to formulate, solve, query, and modify optimization problems.
It works with programming languages including C, C++, Java, Visual Basic, .NET, Delphi, Python, and R.
Coupled with R’s extensive statistical and data-mining tools, the LINDO API's R interface offers seamless possibilities in statistical analysis and optimization.
LINDO solvers can also be called from MATLAB.
The LINDO package contains Stochastic, Linear, Nonlinear (convex & nonconvex/Global), Quadratic, Quadratically Constrained, Second Order Cone and Integer solvers.
It provides tools for analysis of infeasible linear, integer and nonlinear models.
LINDO supports Multiple Objective Optimization. For linear models, users can provide a prioritized list of objective functions, and LINDO will perform Lexico/Pre-emptive priority optimization.
The Multi-Start NLP Solver in LINDO makes it possible for users to specify a target value for the objective function. As soon as any multi-start thread achieves a specified target all threads stop.
With the release of LINDO API 7.0, LINDO stochastic functionality allows users to incor
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https://en.wikipedia.org/wiki/Nuclear%20drip%20line
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The nuclear drip line is the boundary beyond which atomic nuclei are unbound with respect to the emission of a proton or neutron.
An arbitrary combination of protons and neutrons does not necessarily yield a stable nucleus. One can think of moving up or to the right across the table of nuclides by adding a proton or a neutron, respectively, to a given nucleus. However, adding nucleons one at a time to a given nucleus will eventually lead to a newly formed nucleus that immediately decays by emitting a proton (or neutron). Colloquially speaking, the nucleon has leaked or dripped out of the nucleus, hence giving rise to the term drip line.
Drip lines are defined for protons and neutrons at the extreme of the proton-to-neutron ratio; at p:n ratios at or beyond the drip lines, no bound nuclei can exist. While the location of the proton drip line is well known for many elements, the location of the neutron drip line is only known for elements up to neon.
General description
Nuclear stability is limited to those combinations of protons and neutrons described by the chart of the nuclides, also called the valley of stability. The boundaries of this valley are the neutron drip line on the neutron-rich side, and the proton drip line on the proton-rich side. These limits exist because of particle decay, whereby an exothermic nuclear transition can occur by the emission of one or more nucleons (not to be confused with particle decay in particle physics). As such, the drip line may be defined as the boundary beyond which proton or neutron separation energy becomes negative, favoring the emission of a particle from a newly formed unbound system.
Allowed transitions
When considering whether a specific nuclear transmutation, a reaction or a decay, is energetically allowed, one only needs to sum the masses of the initial nucleus/nuclei and subtract from that value the sum of the masses of the product particles. If the result, or Q-value, is positive, then the transmutation is al
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https://en.wikipedia.org/wiki/Victor-Am%C3%A9d%C3%A9e%20Lebesgue
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Victor-Amédée Lebesgue, sometimes written Le Besgue, (2 October 1791, Grandvilliers (Oise) – 10 June 1875, Bordeaux (Gironde)) was a mathematician working on number theory. He was elected a member of the Académie des sciences in 1847.
See also
Catalan's conjecture
Proof of Fermat's Last Theorem for specific exponents
Lebesgue–Nagell type equations
Publications
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https://en.wikipedia.org/wiki/Polyspermy
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In biology, polyspermy describes the fertilization of an egg by more than one sperm. Diploid organisms normally contain two copies of each chromosome, one from each parent. The cell resulting from polyspermy, on the other hand, contains three or more copies of each chromosome—one from the egg and one each from multiple sperm. Usually, the result is an unviable zygote. This may occur because sperm are too efficient at reaching and fertilizing eggs due to the selective pressures of sperm competition. Such a situation is often deleterious to the female: in other words, the male–male competition among sperm spills over to create sexual conflict.
Physiological polyspermy
Physiological polyspermy happens when the egg normally accepts more than one sperm but only one of the multiple sperm will fuse its nucleus with the nucleus of the egg. Physiological polyspermy is present in some species of vertebrates and invertebrates. Some species utilize physiological polyspermy as the proper mechanism for developing their offspring. Some of these animals include birds, ctenophora, reptiles and amphibians. Some vertebrates that are both amniote or anamniote, including urodele amphibians, cartilaginous fish, birds and reptiles, undergo physiological polyspermy because of the internal fertilization of their yolky eggs. Sperm triggers egg activation by the induction of free calcium ion concentration in the cytoplasm of the egg. This induction plays a very critical role in both physiological polyspermy and monomeric polyspermy species. The rise in calcium causes activation of the egg. The egg will then be altered on both a biochemical and morphological level. In mammals as well as sea urchins, the sudden rise in calcium concentration occurs because of the influx of calcium ions within the egg. These calcium ions are responsible for the cortical granule reaction, and are also stored in the egg's endoplasmic reticulum.
Unlike physiological polyspermy, monospermic fertilization deals wit
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https://en.wikipedia.org/wiki/Parasite%20experiment
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In experimental physics, and particularly in high energy and nuclear physics, a parasite experiment or parasitic experiment is an experiment performed using a big particle accelerator or other large facility, without interfering with the scheduled experiments of that facility. This allows the experimenters to proceed without the usual competitive time scheduling procedure. These experiments may be instrument tests or experiments whose scientific interest has not been clearly established.
Further reading
Experimental particle physics
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https://en.wikipedia.org/wiki/Unraid
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Unraid is a proprietary Linux-based operating system designed to run on home media server setups that operates as a network-attached storage device, application server, and virtualization host. Unraid is proprietary software developed and maintained by Lime Technology, Inc. Users of the software are encouraged to write and use plugins and Docker applications to extend the functionality of their systems.
Features
Unraid's primary feature is the ability to easily create and manage RAID arrays in hardware-agnostic ways, allowing users to use nearly any combination of hard drives to create an array, regardless of model, capacity, or connection type. Since Unraid saves data to individual drives rather than spreading single files out over multiple drives, users can create shares, which are groups of files that can be written to multiple drives (as determined by the user or system) and allow easy access and management by users.
Unraid also allows users to create Docker containers or virtual machines to host applications on the system. For example, a user could use a pre-made Docker container to host applications such as Plex, Jellyfin, and others.
Unraid's user license is attached to a specific USB flash drive, which may be linked to a user's forum account.
Technical specifications
Unraid is based on Linux Slackware.
Supported filesystems: XFS, Btrfs, ZFS and ReiserFS. ReiserFS is only for legacy reasons and for backward compatibility, and as a main-rule, shouldn't be used on new implementations.
GPL compliance
Unraid uses the Linux kernel and its filesystems. It most notably contains a greatly modified version of Linux md facilities named . The source code is distributed as part of the USB system image and is visible in the Unraid OS in . can be used to extract the file from without booting.
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https://en.wikipedia.org/wiki/Inverse%20Pythagorean%20theorem
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In geometry, the inverse Pythagorean theorem (also known as the reciprocal Pythagorean theorem or the upside down Pythagorean theorem) is as follows:
Let , be the endpoints of the hypotenuse of a right triangle . Let be the foot of a perpendicular dropped from , the vertex of the right angle, to the hypotenuse. Then
This theorem should not be confused with proposition 48 in book 1 of Euclid's Elements, the converse of the Pythagorean theorem, which states that if the square on one side of a triangle is equal to the sum of the squares on the other two sides then the other two sides contain a right angle.
Proof
The area of triangle can be expressed in terms of either and , or and :
given , and .
Using the Pythagorean theorem,
as above.
Special case of the cruciform curve
The cruciform curve or cross curve is a quartic plane curve given by the equation
where the two parameters determining the shape of the curve, and are each .
Substituting with and with gives
Inverse-Pythagorean triples can be generated using integer parameters and as follows.
Application
If two identical lamps are placed at and , the theorem and the inverse-square law imply that the light intensity at is the same as when a single lamp is placed at .
See also
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https://en.wikipedia.org/wiki/Zeeman%20effect
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The Zeeman effect (; ) is the effect of splitting of a spectral line into several components in the presence of a static magnetic field. It is named after the Dutch physicist Pieter Zeeman, who discovered it in 1896 and received a Nobel prize for this discovery. It is analogous to the Stark effect, the splitting of a spectral line into several components in the presence of an electric field. Also similar to the Stark effect, transitions between different components have, in general, different intensities, with some being entirely forbidden (in the dipole approximation), as governed by the selection rules.
Since the distance between the Zeeman sub-levels is a function of magnetic field strength, this effect can be used to measure magnetic field strength, e.g. that of the Sun and other stars or in laboratory plasmas.
The Zeeman effect is very important in applications such as nuclear magnetic resonance spectroscopy, electron spin resonance spectroscopy, magnetic resonance imaging (MRI) and Mössbauer spectroscopy. It may also be utilized to improve accuracy in atomic absorption spectroscopy.
A theory about the magnetic sense of birds assumes that a protein in the retina is changed due to the Zeeman effect.
When the spectral lines are absorption lines, the effect is called inverse Zeeman effect.
Nomenclature
Historically, one distinguishes between the normal and an anomalous Zeeman effect (discovered by Thomas Preston in Dublin, Ireland). The anomalous effect appears on transitions where the net spin of the electrons is non-zero. It was called "anomalous" because the electron spin had not yet been discovered, and so there was no good explanation for it at the time that Zeeman observed the effect. Wolfgang Pauli recalled that when asked by a colleague as to why he looked unhappy, he replied, "How can one look happy when he is thinking about the anomalous Zeeman effect?"
At higher magnetic field strength the effect ceases to be linear. At even higher field strengths,
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https://en.wikipedia.org/wiki/6
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6 (six) is the natural number following 5 and preceding 7. It is a composite number and the smallest perfect number.
In mathematics
Six is the smallest positive integer which is neither a square number nor a prime number. It is the second smallest composite number after four, equal to the sum and the product of its three proper divisors (, and ). As such, 6 is the only number that is both the sum and product of three consecutive positive numbers. It is the smallest perfect number, which are numbers that are equal to their aliquot sum, or sum of their proper divisors. It is also the largest of the four all-Harshad numbers (1, 2, 4, and 6).
6 is a pronic number and the only semiprime to be. It is the first discrete biprime (2 × 3) which makes it the first member of the (2 × q) discrete biprime family, where q is a higher prime. All primes above 3 are of the form 6n ± 1 for n ≥ 1.
As a perfect number:
6 is related to the Mersenne prime 3, since . (The next perfect number is 28.)
6 is the only even perfect number that is not the sum of successive odd cubes.
6 is the root of the 6-aliquot tree, and is itself the aliquot sum of only one other number; the square number, .
Six is the first unitary perfect number, since it is the sum of its positive proper unitary divisors, without including itself. Only five such numbers are known to exist; sixty (10 × 6) and ninety (15 × 6) are the next two.
All integers that are multiples of 6 are pseudoperfect (all multiples of a pseudoperfect number are pseudoperfect). Six is also the smallest Granville number, or -perfect number.
Unrelated to 6's being a perfect number, a Golomb ruler of length 6 is a "perfect ruler". Six is a congruent number.
6 is the second primary pseudoperfect number, and harmonic divisor number. It is also the second superior highly composite number, and the last to also be a primorial.
There are 6 non-equivalent ways in which 100 can be expressed as the sum of two prime numbers: (3 + 97), (11 + 89),
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https://en.wikipedia.org/wiki/Deception%20in%20animals
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Deception in animals is the transmission of misinformation by one animal to another, of the same or different species, in a way that propagates beliefs that are not true.
Mimicry and camouflage enable animals to appear to be other than they are. Prey animals may appear as predators, or vice versa; both predators and prey may be hard to see (crypsis), or may be mistaken for other objects (mimesis). In Batesian mimicry, harmless animals may appear to be distasteful or poisonous. In automimicry, animals may have eyespots in less important parts of the body than the head, helping to distract attack and increase the chance of survival.
In more active forms of anti-predator adaptation, animals may feign death when they detect a predator, or may quickly conceal themselves or take action to distract a predator, such as when a cephalopod releases ink. In deimatic behaviour, a harmless animal adopts a threatening pose or displays startling, brightly coloured parts of its body to startle a predator or rival.
Some animals may use tactical deception, with behaviour that is deployed in a way that other animals misinterpret what is happening to the advantage of the agent. Some of the evidence for this is anecdotal, but in the great apes in particular, experimental studies in ethology suggest that deception is actively practised by some animals.
Overview
Some types of deception in animals are completely involuntary (e.g. disruptive coloration), but others are under voluntary control and may involve an element of learning. Most instances of voluntary deception in animals involve a simple behaviour, such as a cat arching its back and raising its hackles, to make itself appear larger than normal when attacked. There are relatively few examples of animal behaviour which might be attributed to the manipulative type of deception which we know occurs in humans, i.e. "tactical deception". It has been argued that true deception assumes the deceiver knows that (1) other animals have mi
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https://en.wikipedia.org/wiki/Ovine%20gammaherpesvirus%202
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Ovine gammaherpesvirus 2 (OvHV-2) is a species of virus in the genus Macavirus, subfamily Gammaherpesvirinae, family Herpesviridae, and order Herpesvirales.
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https://en.wikipedia.org/wiki/Diet%20and%20Nutrition%20Association
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The Diet and Nutrition Association (, KOST) is a trade union representing nutritionists and people in related jobs, in Denmark.
The union was founded in 1923, as the Food Economists' Association, and adopted its current name in 2005. Long a member of the Confederation of Professionals in Denmark, since 2019 it has been affiliated to its successor, the Danish Trade Union Confederation. It had about 9,000 members in 2006, and 8,230 members in 2018.
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https://en.wikipedia.org/wiki/Differentiation%20of%20trigonometric%20functions
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The differentiation of trigonometric functions is the mathematical process of finding the derivative of a trigonometric function, or its rate of change with respect to a variable. For example, the derivative of the sine function is written sin′(a) = cos(a), meaning that the rate of change of sin(x) at a particular angle x = a is given by the cosine of that angle.
All derivatives of circular trigonometric functions can be found from those of sin(x) and cos(x) by means of the quotient rule applied to functions such as tan(x) = sin(x)/cos(x). Knowing these derivatives, the derivatives of the inverse trigonometric functions are found using implicit differentiation.
Proofs of derivatives of trigonometric functions
Limit of sin(θ)/θ as θ tends to 0
The diagram at right shows a circle with centre O and radius r = 1. Let two radii OA and OB make an arc of θ radians. Since we are considering the limit as θ tends to zero, we may assume θ is a small positive number, say 0 < θ < ½ π in the first quadrant.
In the diagram, let R1 be the triangle OAB, R2 the circular sector OAB, and R3 the triangle OAC. The area of triangle OAB is:
The area of the circular sector OAB is , while the area of the triangle OAC is given by
Since each region is contained in the next, one has:
Moreover, since in the first quadrant, we may divide through by ½ , giving:
In the last step we took the reciprocals of the three positive terms, reversing the inequities.
We conclude that for 0 < θ < ½ π, the quantity is always less than 1 and always greater than cos(θ). Thus, as θ gets closer to 0, is "squeezed" between a ceiling at height 1 and a floor at height , which rises towards 1; hence sin(θ)/θ must tend to 1 as θ tends to 0 from the positive side:For the case where θ is a small negative number –½ π < θ < 0, we use the fact that sine is an odd function:
Limit of (cos(θ)-1)/θ as θ tends to 0
The last section enables us to calculate this new limit relatively easily. This is done by employing
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https://en.wikipedia.org/wiki/Marconi%20Transistorised%20Automatic%20Computer
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The Marconi Transistorized Automatic Computer was the first all-transistor computer built by Britain's Marconi Company. It was designed and manufactured from around 1959.
The computer employed germanium transistors which by this time were sufficiently reliable in room temperatures kept below about 23 degrees C. The type S3301 was a 500 kHz clocked, 20-bit word machine with two Mullard core memory stores providing 4k of 20-bit data. The internal CPU logic was synchronised to even and odd clock signals and special signals generated via microinstruction diode boards. The memory logic had slow and fast loops to speed the transfer of sequential data bursts. A facility was provided to microstep through instructions to help with fault-finding. Processor status bits were provided, with machine instructions being decoded from 6 bits in the current address memory word. Double word data had the MSB designated a sign bit, coded as binary fractions (-1 to +1), for the square root, multiply and divide instructions. The instruction set had the usual functions based on three registers named A, B and D (C was the current address in memory register, also called M). An additional instruction assisted with checksum calculation for data transferred to and from main data stores (viz. Sperry Rand magnetic drums).
Applications included marking up radar screens with aircraft information and providing data processing for operators in a nuclear power station. Apart from transistor failure, other common faults included power supply capacitors 'drying out' resulting in excess ripple, and poor connections on the input/output highway. Paper tape peripherals had their own poor reliability, influenced to some degree of operator usage.
Surviving computers (ex power station) are on display at the National Museum of Computing (located in Bletchley Park) and Jim Austin's collection near the University of York. The National Museum system is operational. Copies of original manuals and documentation ar
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https://en.wikipedia.org/wiki/Mevalonate%20kinase
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Mevalonate kinase is an enzyme (specifically a kinase) that in humans is encoded by the MVK gene. Mevalonate kinases are found in a wide variety of organisms from bacteria to mammals. This enzyme catalyzes the following reaction:
.
Function
Mevalonate is a key intermediate, and mevalonate kinase a key early enzyme, in isoprenoid and sterol synthesis. As the second enzyme in the Mevalonate pathway, it catalyzes the phosphorylation of Mevalonic acid to produce Mevalonate-5-phosphate. A reduction in mevalonate kinase activity to around 5-10% of its typical value is associated with the mevalonate kinase deficiency (MVD) resulting in accumulation of intermediate mevalonic acid.
Clinical significance
Defects can be associated with hyperimmunoglobulinemia D with recurrent fever.
Mevalonate kinase deficiency caused by mutation of this gene results in mevalonic aciduria, a disease characterized psychomotor retardation, failure to thrive, hepatosplenomegaly, anemia and recurrent febrile crises. Defects in this gene also cause hyperimmunoglobulinaemia D and periodic fever syndrome, a disorder characterized by recurrent episodes of fever associated with lymphadenopathy, arthralgia, gastrointestinal dismay and skin rash. The symptoms of the disease typically start at infancy and may be additionally triggered by stress or bacterial infection. Children with mevalonate kinase deficiency may remain undiagnosed for a long time as there is not enough scientific data at the moment to accurately diagnose children with the disease.
See also
Mevalonic aciduria
Mevalonic acid
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https://en.wikipedia.org/wiki/Odd%20number%20theorem
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The odd number theorem is a theorem in strong gravitational lensing which comes directly from differential topology.
The theorem states that the number of multiple images produced by a bounded transparent lens must be odd.
Formulation
The gravitational lensing is a thought to mapped from what's known as image plane to source plane following the formula :
.
Argument
If we use direction cosines describing the bent light rays, we can write a vector field on plane .
However, only in some specific directions , will the bent light rays reach the observer, i.e., the images only form where . Then we can directly apply the Poincaré–Hopf theorem .
The index of sources and sinks is +1, and that of saddle points is −1. So the Euler characteristic equals the difference between the number of positive indices and the number of negative indices . For the far field case, there is only one image, i.e., . So the total number of images is , i.e., odd. The strict proof needs Uhlenbeck's Morse theory of null geodesics.
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https://en.wikipedia.org/wiki/Successor%20cardinal
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In set theory, one can define a successor operation on cardinal numbers in a similar way to the successor operation on the ordinal numbers. The cardinal successor coincides with the ordinal successor for finite cardinals, but in the infinite case they diverge because every infinite ordinal and its successor have the same cardinality (a bijection can be set up between the two by simply sending the last element of the successor to 0, 0 to 1, etc., and fixing ω and all the elements above; in the style of Hilbert's Hotel Infinity). Using the von Neumann cardinal assignment and the axiom of choice (AC), this successor operation is easy to define: for a cardinal number κ we have
,
where ON is the class of ordinals. That is, the successor cardinal is the cardinality of the least ordinal into which a set of the given cardinality can be mapped one-to-one, but which cannot be mapped one-to-one back into that set.
That the set above is nonempty follows from Hartogs' theorem, which says that for any well-orderable cardinal, a larger such cardinal is constructible. The minimum actually exists because the ordinals are well-ordered. It is therefore immediate that there is no cardinal number in between κ and κ+. A successor cardinal is a cardinal that is κ+ for some cardinal κ. In the infinite case, the successor operation skips over many ordinal numbers; in fact, every infinite cardinal is a limit ordinal. Therefore, the successor operation on cardinals gains a lot of power in the infinite case (relative the ordinal successorship operation), and consequently the cardinal numbers are a very "sparse" subclass of the ordinals. We define the sequence of alephs (via the axiom of replacement) via this operation, through all the ordinal numbers as follows:
and for λ an infinite limit ordinal,
If β is a successor ordinal, then is a successor cardinal. Cardinals that are not successor cardinals are called limit cardinals; and by the above definition, if λ is a limit ordinal, then
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https://en.wikipedia.org/wiki/Plant%20propagation
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Plant propagation is the process by which new plants grow from various sources, including seeds, cuttings, and other plant parts. Plant propagation can refer to both man-made or natural dispersal of seeds.
Propagation typically occurs as a step in the overall cycle of plant growth. For seeds, it happens after ripening and dispersal; for vegetative parts, it happens after detachment or pruning; for asexually-reproducing plants, such as strawberry, it happens as the new plant develops from existing parts. Plant propagation can be divided into four basic types: sexual, asexual (vegetative), layering, and grafting.
Countless plants are propagated each day in horticulture and agriculture. The materials commonly used for plant propagation are seeds and cuttings.
Sexual propagation
Seeds and spores can be used for reproduction (e.g. sowing). Seeds are typically produced from sexual reproduction within a species because genetic recombination has occurred. A plant grown from seeds may have different characteristics from its parents. Some species produce seeds that require special conditions to germinate, such as cold treatment. The seeds of many Australian plants and plants from southern Africa and the American west require smoke or fire to germinate. Some plant species, including many trees, do not produce seeds until they reach maturity, which may take many years. Seeds can be difficult to acquire and some plants do not produce seed at all. Some plants (like certain plants modified using genetic use restriction technology) may produce seed, but not a fertile seed. In certain cases, this is done to prevent the accidental spreading of these plants, for example by birds and other animals.
Asexual propagation
Plants have a number of mechanisms for asexual or vegetative reproduction. Some of these have been taken advantage of by horticulturists and to multiply or clone plants rapidly. Humans may utilize these processes as propagation methods, such as tissue culture and gr
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https://en.wikipedia.org/wiki/Birnenhonig
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Birnenhonig () is a syrup made from pears in central Switzerland. In North America it is known as Pear Butter. It is very similar to the Belgian spread sirop de Liège.
Production
The pears are boiled and then pressed to obtain juice. The liquid is then heated for six to seven hours. The end product is sweet, opaque, creamy, dark brown and is consumed as a spread on bread or as a main ingredient for Luzerner Lebkuchen, a type of gingerbread. During the Second World War, milk with Birnenhonig was often consumed as an alternative to milky coffee because of the scarcity of coffee.
See also
Apple butter
List of spreads
Sirop de Liège
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https://en.wikipedia.org/wiki/Field-sequential%20color%20system
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A field-sequential color system (FSC) is a color television system in which the primary color information is transmitted in successive images and which relies on the human vision system to fuse the successive images into a color picture. One field-sequential system was developed by Peter Goldmark for CBS, which was its sole user in commercial broadcasting. It was first demonstrated to the press on September 4, 1940, and first shown to the general public on January 12, 1950. The Federal Communications Commission adopted it on October 11, 1950, as the standard for color television in the United States, but it was later withdrawn.
History
The use of sequential color systems for moving images predates the invention of fully electronic television. Described at the time as "additive" rather than sequential color systems, two-color Kinemacolor, in commercial use since 1906, and its predecessor three-color format, invented by Edward Raymond Turner and patented in 1899, were both sequential natural color systems for use with motion picture film. They utilized black-and-white film and rotating color filter wheels to record the amount of each color in the scene on alternating frames of the film, so that when the frames were projected by light of similar colors at a sufficiently rapid rate, those colors blended together in the color center of the viewer's occipital lobe, producing a wider range of hues.
Due to litigation by William Friese-Greene, Kinemacolor ended up in the public domain in 1915, after which several derivative sequential color processes (such as Friese-Greene's Biocolour and the original Prisma Color) were developed. Some were brought to the point of being publicly shown, but during the 1920s they could not compete with rival bipack and other subtractive color processes, which were free of color flicker and did not require special projection equipment—the final multicolored images were right there on the film as transparent coloring matter.
Operation
The
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https://en.wikipedia.org/wiki/Oblique%20ridges%20of%20scapula
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The oblique ridges cross the subscapular fossa from superomedial to inferiolateral (parallel to scapular spine). These ridges are formed by intramuscular tendons of the subscapularis muscle.
The costal or ventral surface of the scapula presents a broad concavity, the subscapular fossa. The medial two-thirds of the fossa are marked by several oblique ridges, which run lateralward and upward. The ridges give attachment to the tendinous insertions, and the surfaces between them to the fleshy fibers, of the subscapularis muscle.
Additional images
See also
Subscapular fossa
Subscapularis muscle
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https://en.wikipedia.org/wiki/Eddington%20number
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In astrophysics, the Eddington number, , is the number of protons in the observable universe. Eddington originally calculated it as about ; current estimates make it approximately .
The term is named for British astrophysicist Arthur Eddington, who in 1940 was the first to propose a value of and to explain why this number might be important for physical cosmology and the foundations of physics.
History
Eddington argued that the value of the fine-structure constant, α, could be obtained by pure deduction. He related α to the Eddington number, which was his estimate of the number of protons in the universe. This led him in 1929 to conjecture that α was exactly 1/136. He devised a "proof" that NEdd = 136 × 2256, or about 1.57×1079. Other physicists did not adopt this conjecture and did not accept his argument.
In the late 1930s, the best experimental value of the fine-structure constant, α, was approximately 1/137. Eddington then argued, from aesthetic and numerological considerations, that α should be exactly 1/137.
Current estimates of NEdd point to a value of about . These estimates assume that all matter can be taken to be hydrogen and require assumed values for the number and size of galaxies and stars in the universe.
Attempts to find a mathematical basis for this dimensionless constant have continued up to the present time.
During a course of lectures that he delivered in 1938 as Tarner Lecturer at Trinity College, Cambridge, Eddington averred that:
This large number was soon named the "Eddington number".
Shortly thereafter, improved measurements of α yielded values closer to 1/137, whereupon Eddington changed his "proof" to show that α had to be exactly 1/137.
Recent theory
The most precise value of α (obtained experimentally in 2012) is:
Consequently, no reliable source any longer maintains that α is the reciprocal of an integer. Nor does anyone take seriously a mathematical relationship between α and NEdd.
On possible roles for NEdd in contempor
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https://en.wikipedia.org/wiki/Language%2C%20Truth%2C%20and%20Logic
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Language, Truth and Logic is a 1936 book about meaning by the philosopher Alfred Jules Ayer, in which the author defines, explains, and argues for the verification principle of logical positivism, sometimes referred to as the criterion of significance or criterion of meaning. Ayer explains how the principle of verifiability may be applied to the problems of philosophy. Language, Truth and Logic brought some of the ideas of the Vienna Circle and the logical empiricists to the attention of the English-speaking world.
Historical background
According to Ayer's autobiographical book, Part of My Life, it was work he started in the summer and autumn of 1933 that eventually led to Language, Truth and Logic, specifically Demonstration of the Impossibility of Metaphysics—later published in Mind under the editorship of G.E. Moore. The title of the book was taken ("To some extent plagiarized" according to Ayer) from Friedrich Waismann's Logik, Sprache, Philosophie.
Criterion of meaning
According to Ayer, analytic statements are tautologies. A tautology is a statement that is necessarily true, true by definition, and true under any conditions. A tautology is a repetition of the meaning of a statement, using different words or symbols. According to Ayer, the statements of logic and mathematics are tautologies. Tautologies are true by definition, and thus their validity does not depend on empirical testing.
Synthetic statements, or empirical propositions, assert or deny something about the real world. The validity of synthetic statements is not established merely by the definition of the words or symbols they contain. According to Ayer, if a statement expresses an empirical proposition, then the validity of the proposition is established by its empirical verifiability.
Propositions are statements that have conditions under which they can be verified. By the verification principle, meaningful statements have conditions under which their validity can be affirmed or denied.
Sta
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https://en.wikipedia.org/wiki/Blue%20only%20mode
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Blue Only mode is a special display mode on display units such as projectors and television sets whereby only the blue pixels or the blue cathode ray tube is used to generate the image.
Displays featuring this mode are prominent especially in the broadcast area because it allows for hue and saturation to be adjusted quickly and accurately. Professional monitors may feature a dedicated button on the front of the display to activate blue only mode.
Test images for Blue Only Mode
In general, all test pattern with a color bar, that includes red, green, blue, and the complementary colors cyan, magenta and yellow can be used to adjust hue and saturation in blue only mode.
Particularly often the SMPTE test pattern or the HD version of the SMPTE is used for hue and saturation adjustment. These are in many cases already integrated in the recording and playback devices in the professional sector and are always available.
Also the Blue Only-test image of the company Burosch audio video technology is suitable for use with a blue filter foil or just the Blue Only mode of a display.
In addition to hue and saturation adjustment, it's possible to even adjust brightness, contrast and to check the transmission path with the burosch test.
The above-mentioned test pattern from the Burosch company represents an update of the traditional HD SMPTE test pattern, with additional test zones for complete image control and optimization.
How the Blue Only Mode works
In Blue Only mode only the blue pixels of a display render the picture on the screen - or, for CRT displays, the blue cathode ray tube. Thus we see only the blue channel of the image, but rather blue tinted than black and white. Areas with blue color in it appear bright and those without blue color appear dark or black.
A blue color with RGB values of 0 0 255 therefore appears bright. A red area (255 0 0) or a green surface (0 255 0) appears black.
Below - or in some test images above - the color bars are reference areas, that
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https://en.wikipedia.org/wiki/Minimal%20infective%20dose
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The concept of a minimal infective dose (MID), also known as the infectious dose, has traditionally been used for infectious bacteria that contaminate foods. MID was defined as the number of bacteria ingested (the dose) from which a pathology is observed in the consumer. Examples such as this are found in textbooks: to cause gastrointestinal disorders, the food must contain more than 100,000 Salmonella per gram. However, in such a formulation, an inaccuracy immediately becomes apparent: to know the dose ingested, concentration is not enough. It is also necessary to know the mass of the portion:
d\ =\ c \times m
where:
d = number of bacteria i.e. dose
c = concentration of bacteria
m = mass
Nevertheless, this formulation has served as a basis for reasoning to establish the maximum concentrations permitted by the microbiological regulatory criteria intended to protect the health of consumers. Thus in 1992, as the outbreaks previously caused by Listeria monocytogenes involved only food containing more than 1000 L. monocytogenes cells per gram, lawmakers on both sides of the Atlantic - keeping a margin of safety - fixed its maximum concentration at 100 L. monocytogenes per gram.
Dose-effect relationship and dose-response relationship
The concept of a dose-response relationship developed from 1995 onward, as quantitative risk assessment matured as a discipline within the field of food safety.
An infectious bacterium in a food can cause various effects: diarrhea, vomiting, sepsis, meningitis, abortion, Guillain-Barré syndrome, death, etc. As the dose increases, the severity of the pathological effects increases, and a "dose-effect relationship" can often be established. For example, the higher the dose of Salmonella, the more diarrhea occurs soon after ingestion.
However, among people who have ingested the same dose, not all are affected. The proportion of people affected is called the response. The dose-response relationship for a given effect (e.g., diarrhea) is the
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https://en.wikipedia.org/wiki/Grothendieck%20trace%20theorem
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In functional analysis, the Grothendieck trace theorem is an extension of Lidskii's theorem about the trace and the determinant of a certain class of nuclear operators on Banach spaces, the so-called -nuclear operators. The theorem was proven in 1955 by Alexander Grothendieck. Lidskii's theorem does not hold in general for Banach spaces.
The theorem should not be confused with the Grothendieck trace formula from algebraic geometry.
Grothendieck trace theorem
Given a Banach space with the approximation property and denote its dual as .
⅔-nuclear operators
Let be a nuclear operator on , then is a -nuclear operator if it has a decomposition of the form
where and and
Grothendieck's trace theorem
Let denote the eigenvalues of counted with their algebraic multiplicities. If
then the following equalities hold:
and for the Fredholm determinant
See also
Literature
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https://en.wikipedia.org/wiki/Similarity%20system%20of%20triangles
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A similarity system of triangles is a specific configuration involving a set of triangles. A set of triangles is considered a configuration when all of the triangles share a minimum of one incidence relation with one of the other triangles present in the set. An incidence relation between triangles refers to when two triangles share a point. For example, the two triangles to the right, and , are a configuration made up of two incident relations, since points and are shared. The triangles that make up configurations are known as component triangles. Triangles must not only be a part of a configuration set to be in a similarity system, but must also be directly similar. Direct similarity implies that all angles are equal between two given triangle and that they share the same rotational sense. As is seen in the adjacent images, in the directly similar triangles, the rotation of onto and onto occurs in the same direction. In the opposite similar triangles, the rotation of onto and onto occurs in the opposite direction. In sum, a configuration is a similarity system when all triangles in the set, lie in the same plane and the following holds true: if there are n triangles in the set and n − 1 triangles are directly similar, then n triangles are directly similar.
Background
J.G. Mauldon introduced the idea of similarity systems of triangles in his paper in Mathematics Magazine "Similar Triangles". Mauldon began his analyses by examining given triangles for direct similarity through complex numbers, specifically the equation . He then furthered his analyses to equilateral triangles, showing that if a triangle satisfied the equation when , it was equilateral. As evidence of this work, he applied his conjectures on direct similarity and equilateral triangles in proving Napoleon's theorem. He then built off Napoleon by proving that if an equilateral triangle was constructed with equilateral triangles incident on each vertex, the midpoints of the connecting
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https://en.wikipedia.org/wiki/Asynchronous%20communication%20mechanism
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The role of an asynchronous communication mechanism (ACM) is to synchronize the transfer of data in a system between a writing process and a reading process operating concurrently.
Description
The mechanism by which the ACM performs its tasks varies heavily depending upon the situation in which the ACM is employed. A possible scenario is the writer outputs data at a higher rate than the reader can process it. Without an ACM, one of two things will happen:
If the system incorporates a buffer between processes (e.g., a Unix shell pipe), then data will accumulate and be processed at the reader's maximum rate. There are some circumstances in which this is a desirable characteristic (e.g. piping a file over SSH, or if all data in the set is important, and the reader's output does not need to be synchronised with the input).
If it is necessary to synchronize the input of the writer with the output of the reader, then the ACM can interface with the two systems, and make active decisions on how to handle each packet of information. If, for example, maximum synchronization is required, the ACM could be configured to drop packets, and output the newest packets at the reader's maximum speed.
Alternatively, if there is no buffer, some data may be lost. If this is undesirable, the ACM can provide this buffer, or process the data in such a way that minimal information is lost.
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https://en.wikipedia.org/wiki/Orders%20of%20magnitude%20%28power%29
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This page lists examples of the power in watts produced by various sources of energy. They are grouped by orders of magnitude from small to large.
Below 1 W
1 to 102 W
103 to 108 W
The productive capacity of electrical generators operated by utility companies is often measured in MW. Few things can sustain the transfer or consumption of energy on this scale; some of these events or entities include: lightning strikes, naval craft (such as aircraft carriers and submarines), engineering hardware, and some scientific research equipment (such as supercolliders and large lasers).
For reference, about 10,000 100-watt lightbulbs or 5,000 computer systems would be needed to draw 1 MW. Also, 1 MW is approximately 1360 horsepower. Modern high-power diesel-electric locomotives typically have a peak power of 3–5 MW, while a typical modern nuclear power plant produces on the order of 500–2000 MW peak output.
109 to 1014 W
1015 to 1026 W
Over 1027 W
See also
Orders of magnitude (energy)
Orders of magnitude (voltage)
World energy resources and consumption
International System of Units (SI)
SI prefix
Notes
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https://en.wikipedia.org/wiki/Breadboard
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A breadboard, solderless breadboard, or protoboard is a construction base used to build semi-permanent prototypes of electronic circuits. Unlike a perfboard or stripboard, breadboards do not require soldering or destruction of tracks and are hence reusable. For this reason, breadboards are also popular with students and in technological education.
A variety of electronic systems may be prototyped by using breadboards, from small analog and digital circuits to complete central processing units (CPUs).
Compared to more permanent circuit connection methods, modern breadboards have high parasitic capacitance, relatively high resistance, and less reliable connections, which are subject to jostle and physical degradation. Signaling is limited to about 10 MHz, and not everything works properly even well below that frequency.
History
In the early days of radio, amateurs nailed bare copper wires or terminal strips to a wooden board (often literally a bread cutting board) and soldered electronic components to them. Sometimes a paper schematic diagram was first glued to the board as a guide to placing terminals, then components and wires were installed over their symbols on the schematic. Using thumbtacks or small nails as mounting posts was also common.
Breadboards have evolved over time with the term now being used for all kinds of prototype electronic devices. For example, US Patent 3,145,483, was filed in 1961 and describes a wooden plate breadboard with mounted springs and other facilities. US Patent 3,496,419, was filed in 1967 and refers to a particular printed circuit board layout as a Printed Circuit Breadboard. Both examples refer to and describe other types of breadboards as prior art.
In 1960, Orville Thompson of DeVry Technical Institute patented a solderless breadboard connecting rows of holes together with spring metal. In 1971, Ronald Portugal of E&L Instruments patented a similar concept with holes in spacings, the same as DIP IC packages, which b
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https://en.wikipedia.org/wiki/DriveSavers
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DriveSavers, Inc. is a computer hardware data recovery, digital forensics and electronic discovery firm located in Novato, California. It was founded by CEO Jay Hagan and former company President Scott Gaidano in 1985.
History
In 1985, former Jasmine Technologies executives Jay Hagan and Scott Gaidano founded DriveSavers, operating from Gaidano’s condo with $1,400. DriveSavers originally offered both hard drive repair and data recovery services, but the company dropped its drive repair services within its first eight months. In 1992, DriveSavers signed an agreement with SuperMac Technology to assume technical support and warranty obligations for SuperMac Mass Storage Products.
The company merged with Data Recovery Disk Repair in 1994 and retained the DriveSavers name. In 2008, DriveSavers invested two million dollars to build a series of five ISO-certified cleanrooms to disassemble and rebuild damaged hard drives. From 2004-2009, the company grew from 35 to 85 employees.
DriveSavers also works with "the more secretive" branches of government and celebrities. In order to provide comfort and assistance to clients with a data loss situation, DriveSavers has had on staff an individual "data crisis counselor." This counselor has had experience in working for a suicide hotline.
DriveSavers is the only recovery firm licensed with every major hard-drive manufacturer, so their work on a drive does not void the warranty. It can recover data from hard disk drives, solid state drives, smart phones, servers, digital camera media and iOS devices. The company can recover data from T2 and M1-powered Macs with embedded SSD storage. Even with cloud backup, personal data loss is still possible, but can be recovered. The company recovered data from old floppy disks of the deceased creator of Star Trek, Gene Roddenberry, potentially containing lost episodes of the franchise.
DriveSavers is certified HIPAA-compliant, undergoes annual SOC2 Type II reviews and has encryption training
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https://en.wikipedia.org/wiki/Hurricane%20Sandy%3A%20Coming%20Together
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Hurricane Sandy: Coming Together was a one-hour, commercial-free benefit concert television special that aired simulcast in the United States on November 2, 2012 at 8 p.m. ET/CT live from New York City and tape delayed MT and PT. The special raised money for the relief efforts from the aftermath of Hurricane Sandy, which had struck the U.S. Northeast four days earlier. All proceeds went to the American Red Cross.
Production
The concert was an effort of NBC and its affiliated channels, and its origins lay with Today show anchor Matt Lauer suggesting it to NBCUniversal CEO Steve Burke. It featured appearances and musical performances mostly by those associated with the affected areas, especially New Jersey and New York. At least one, Long Island's Billy Joel, had properties damaged by the storm. Organization for the production was put together in a hurry, in the face of logistical and transportation difficulties in the wake of the storm.
The event took place at The Dr. Oz Show Studio 6A at the NBC Studios in 30 Rockefeller Plaza in New York before a small audience. The event followed somewhat in the manner and format of Shelter from the Storm: A Concert for the Gulf Coast, which raised money for the relief efforts from the aftermath of Hurricane Katrina in 2005, and other recent disaster relief telethons.
Approximately $23 million was raised by Hurricane Sandy: Coming Together for the American Red Cross.
Musical guests and performances
The running order of musical performances was:
Christina Aguilera, "Beautiful"
Jon Bon Jovi, "Who Says You Can't Go Home"/"Livin' on a Prayer"
Billy Joel, "Miami 2017 (Seen the Lights Go Out on Broadway)"
Jimmy Fallon, Steven Tyler and Billy Joel (piano and vocals), with Bruce Springsteen (guitar and backing vocals) and Mark Rivera (backing vocals), "Under the Boardwalk"
Steven Tyler, Joe Perry and Brad Whitford (all from Aerosmith), "Dream On"
Sting, "Message in a Bottle"
Mary J. Blige, "The Living Proof"
Bruce Springsteen and
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https://en.wikipedia.org/wiki/SEX%20%28computing%29
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In computing, the SEX assembly language mnemonic has often been used for the "Sign EXtend" machine instruction found in the Motorola 6809. A computer's or CPU's "sex" can also mean the endianness of the computer architecture used. x86 computers do not have the same "byte sex" as HC11 computers, for example. Functions are sometimes needed for computers of different endianness to communicate with each other over the internet, as protocols often use big endian byte coding by default.
On the RCA 1802 series of microprocessors, the SEX, for "SEt X," instruction is used to designate which of the machine's sixteen 16-bit registers is to be the X (index) register.
SEX in software: rarely used jargon
The TLA SEX has humorously been said to stand for Software EXchange, meaning copying of software. As file sharing has sometimes spread computer viruses, it has been stated that “illicit SEX can transmit viral diseases to your computer.” The involvement of FTP servers' /pub directories in this process has led to the name being explained as a contraction of 'pubic'.
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https://en.wikipedia.org/wiki/Flag%20of%20Nigeria
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The flag of Nigeria was designed in 1959 and first officially hoisted on 1 October 1960.
The flag has three vertical bands of green, white, green. The two
green stripes represent natural wealth, and the white represents peace and unity.
Design
The flag is an adaptation of the winning entry from Michael Taiwo Akinkunmi in a competition held in 1959. Akinkunmi was a 23-year-old student at the time he designed the flag. He was studying at Norwood Technical College in London, England, when he saw an advertisement in a newspaper that submissions were being accepted for the design of a new national flag of Nigeria. He submitted a triband design consisting of a white vertical band in the centre, with a green vertical band on each side. The design also contained a radiating red sun in the white vertical centre of the flag. He won the contest, however the judges removed the red sun, leaving only a green and white triband design for the national flag. It is typical for culturally diverse countries such as Nigeria to choose simpler and less complex flag designs in order to avoid inadvertently offending particular ethnic or religious groups. The flag has remained unchanged ever since then. It was first officially used on 1 October 1960, the day Nigeria was granted independence from the United Kingdom.
Nigeria has special ensigns for civil and naval vessels. Some of its states also have flags.
Colour specifications
Other flags
State flags and ensigns
Presidential flags
Military flags
Historical flags
Subnational flags
See also
Coat of arms of Nigeria
Flag of Biafra
Flag of Rhodesia
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https://en.wikipedia.org/wiki/Plant%20collecting
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Plant collecting is the acquisition of plant specimens for the purposes of research, cultivation, or as a hobby. Plant specimens may be kept alive, but are more commonly dried and pressed to preserve the quality of the specimen. Plant collecting is an ancient practice with records of a Chinese botanist collecting roses over 5000 years ago.
Herbaria are collections of preserved plants samples and their associated data for scientific purposes. The largest herbarium in the world exist at the Muséum National d'Histoire Naturelle, in Paris, France. Plant samples in herbaria typically include a reference sheet with information about the plant and details of collection. This detailed and organized system of filing provides horticulturist and other researchers alike with a way to find information about a certain plant, and a way to add new information to an existing plant sample file.
The collection of live plant specimens from the wild, sometimes referred to as plant hunting, is an activity that has occurred for centuries. The earliest recorded evidence of plant hunting was in 1495 BC when botanists were sent to Somalia to collect incense trees for Queen Hatshepsut. The Victorian era saw a surge in plant hunting activity as botanical adventurers explored the world to find exotic plants to bring home, often at considerable personal risk. These plants usually ended up in botanical gardens or the private gardens of wealthy collectors. Prolific plant hunters in this period included William Lobb and his brother Thomas Lobb, George Forrest, Joseph Hooker, Charles Maries and Robert Fortune.
Sample gathering
The first step of plant collection begins with the selection of the sample. When collecting a sample it is important to first make sure that land you are collecting on allows for the removal of natural specimens. The next step after finding a suitable plant for collection is to assign it with a number for record keeping purposes. This number system is up to the individual
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https://en.wikipedia.org/wiki/Regular%20semigroup
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In mathematics, a regular semigroup is a semigroup S in which every element is regular, i.e., for each element a in S there exists an element x in S such that . Regular semigroups are one of the most-studied classes of semigroups, and their structure is particularly amenable to study via Green's relations.
History
Regular semigroups were introduced by J. A. Green in his influential 1951 paper "On the structure of semigroups"; this was also the paper in which Green's relations were introduced. The concept of regularity in a semigroup was adapted from an analogous condition for rings, already considered by John von Neumann. It was Green's study of regular semigroups which led him to define his celebrated relations. According to a footnote in Green 1951, the suggestion that the notion of regularity be applied to semigroups was first made by David Rees.
The term inversive semigroup (French: demi-groupe inversif) was historically used as synonym in the papers of Gabriel Thierrin (a student of Paul Dubreil) in the 1950s, and it is still used occasionally.
The basics
There are two equivalent ways in which to define a regular semigroup S:
(1) for each a in S, there is an x in S, which is called a pseudoinverse, with axa = a;
(2) every element a has at least one inverse b, in the sense that aba = a and bab = b.
To see the equivalence of these definitions, first suppose that S is defined by (2). Then b serves as the required x in (1). Conversely, if S is defined by (1), then xax is an inverse for a, since a(xax)a = axa(xa) = axa = a and (xax)a(xax) = x(axa)(xax) = xa(xax) = x(axa)x = xax.
The set of inverses (in the above sense) of an element a in an arbitrary semigroup S is denoted by V(a). Thus, another way of expressing definition (2) above is to say that in a regular semigroup, V(a) is nonempty, for every a in S. The product of any element a with any b in V(a) is always idempotent: abab = ab, since aba = a.
Examples of regular semigroups
Every group is a r
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https://en.wikipedia.org/wiki/Red%20ribbon
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The red ribbon, as an awareness ribbon, is used as the symbol for the solidarity of people living with HIV/AIDS, and for the awareness and prevention of drug abuse and drunk driving. In Canada the red ribbon represents Canadians with Multiple Sclerosis.
Awareness symbol
The red ribbon is a symbol for Multiple Sclerosis, drunk driving prevention, drug prevention and for the fight against HIV/AIDS. The Red Ribbon Foundation, Mothers Against Drunk Driving (MADD) and the Canadian Multiple Sclerosis Society are examples of organizations that utilize the red ribbon symbol.
MADD is an organization founded in 1980 whose mission is to stop drunk driving, support the victims of this violent crime and prevent underage drinking. Red Ribbon International is an organization founded in 1993 whose main purpose is the education about prevention of the Human Immunodeficiency Virus or HIV, Acquired Immune Deficiency Syndrome Related Complex, ARC and AIDS.
Mothers Against Drunk Driving (MADD) origins
In 1986, MADD started the "Tie One On For Safety" campaign. It is MADD’s longest running and most visible public awareness project. During the holiday season, drivers are encouraged to tie MADD red ribbons to visible locations on their vehicles, or place window decals on their vehicles’ windows. The red ribbons represent the drivers’ commitment to drive safe, sober and buckled up. It also encourages others to designate a sober driver before drinking.
Alcohol, tobacco and other drug prevention awareness origin
The Red Ribbon was used as an awareness symbol made by after DEA Agent Enrique Camarena was kidnapped, tortured, and murdered while working undercover in Guadalajara, Mexico. Citizens in his home town of Calexico, California donned the ribbons to emphasize the need for increased prevention efforts. In 1988, Red Ribbon Week, sponsored by National Family Partnership, became a national campaign. It is celebrated from October 23 through October 31.
AIDS awareness origin
The Red R
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https://en.wikipedia.org/wiki/IT%20risk%20management
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IT risk management is the application of risk management methods to information technology in order to manage IT risk, i.e.:
The business risk associated with the use, ownership, operation, involvement, influence and adoption of IT within an enterprise or organization
IT risk management can be considered a component of a wider enterprise risk management system.
The establishment, maintenance and continuous update of an information security management system (ISMS) provide a strong indication that a company is using a systematic approach for the identification, assessment and management of information security risks.
Different methodologies have been proposed to manage IT risks, each of them divided into processes and steps.
According to the Risk IT framework, this encompasses not only the negative impact of operations and service delivery which can bring destruction or reduction of the value of the organization, but also the benefit enabling risk associated to missing opportunities to use technology to enable or enhance business or the IT project management for aspects like overspending or late delivery with adverse business impact.
Because risk is strictly tied to uncertainty, decision theory should be applied to manage risk as a science, i.e. rationally making choices under uncertainty.
Generally speaking, risk is the product of likelihood times impact (Risk = Likelihood * Impact).
The measure of an IT risk can determined as a product of threat, vulnerability and asset values:
A more current risk management framework for IT Risk would be the TIK framework:
The process of risk management is an ongoing iterative process. It must be repeated indefinitely. The business environment is constantly changing and new threats and vulnerabilities emerge every day. The choice of countermeasures (controls) used to manage risks must strike a balance between productivity, cost, effectiveness of the countermeasure, and the value of the informational asset being protected.
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https://en.wikipedia.org/wiki/Postal%20Alpha%20Numeric%20Encoding%20Technique
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The Postal Alpha Numeric Encoding Technique (PLANET) barcode was used by the United States Postal Service to identify and track pieces of mail during delivery - the Post Office's "CONFIRM" services. It was fully superseded by Intelligent Mail Barcode by January 28, 2013.
Barcode
A PLANET barcode appears either 12 or 14 digits long. The barcode:
identifies mailpiece class and shape
identifies the Confirm Subscriber ID
includes up to 6 digits of additional information that the Confirm subscriber chose, such as a mailing number, mailing campaign ID or customer ID
ends with a check digit
Encoding
Like POSTNET, PLANET encodes the data in half- and full-height bars. Also like POSTNET, PLANET always starts and ends with a full bar (often called a guard rail), and each individual digit is represented by a set of five bars using a two-out-of-five code. However, in POSTNET, the two bars are full bars; in PLANET, the two-of-five are the short bars. As with POSTNET, the check digit is calculated by summing the other characters and calculating the single digit which, when added to the sum, makes the total divisible by 10.
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https://en.wikipedia.org/wiki/Fungal%20immunomodulatory%20protein
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Fungal immunomodulatory proteins (FIPs) are a type of functional compound (other compounds include polysaccharides and triterpenoids) found in various species of fungi. FIPs are part of the immunoglobulin (ig) family, which are structurally similar to human antibodies, and can interact with human peripheral blood mononuclear cells (PBMCs), causing these cells to secrete different types of hormones and regulate cellular activity.
History
The first FIP was discovered in 1989 by Japanese scientist Kohsuke Kino et al. from the water extract of the mycelium of Ganoderma lucidum, and was named Ling Zhi-8 (LZ-8).
From then on, researchers have identified numerous structurally similar proteins from various types of fungi that also share a high degree of genetic similarity as well as physiological activities, and thus coined the term fungal immunomodulatory protein (FIP).
Members of the FIP family
Currently known FIPs are listed below:
LZ-8 from G. lucidum
LZ-9 from G. lucidum
FIP-gts from G. tsugae
FIP-gsi (NCBI DNA Accession number AY987805; Protein Accession number AAX98241) from G. sinensis
GMI (FIP-gmi) (NCBI GI Accession number 310942694; Protein Data Bank Accession number 3KCW_A) from G. microsporum
FIP-tve (NCBI DNA Accession number XM_008037967; Protein Accession number XP_008036158) from Trametes versicolor
FIP-pcp from Poria cocos
FIP-fve (NCBI DNA Accession number GU388420; Protein Accession number ADB24832) from Flammulina velutipes
FIP-vvo from Volvariella volvacea
FIP-aca from Antrodia camphorate
FIP-lrh from Lignosus rhinocerotis
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https://en.wikipedia.org/wiki/Invariant%20%28mathematics%29
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In mathematics, an invariant is a property of a mathematical object (or a class of mathematical objects) which remains unchanged after operations or transformations of a certain type are applied to the objects. The particular class of objects and type of transformations are usually indicated by the context in which the term is used. For example, the area of a triangle is an invariant with respect to isometries of the Euclidean plane. The phrases "invariant under" and "invariant to" a transformation are both used. More generally, an invariant with respect to an equivalence relation is a property that is constant on each equivalence class.
Invariants are used in diverse areas of mathematics such as geometry, topology, algebra and discrete mathematics. Some important classes of transformations are defined by an invariant they leave unchanged. For example, conformal maps are defined as transformations of the plane that preserve angles. The discovery of invariants is an important step in the process of classifying mathematical objects.
Examples
A simple example of invariance is expressed in our ability to count. For a finite set of objects of any kind, there is a number to which we always arrive, regardless of the order in which we count the objects in the set. The quantity—a cardinal number—is associated with the set, and is invariant under the process of counting.
An identity is an equation that remains true for all values of its variables. There are also inequalities that remain true when the values of their variables change.
The distance between two points on a number line is not changed by adding the same quantity to both numbers. On the other hand, multiplication does not have this same property, as distance is not invariant under multiplication.
Angles and ratios of distances are invariant under scalings, rotations, translations and reflections. These transformations produce similar shapes, which is the basis of trigonometry. In contrast, angles and ratios a
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https://en.wikipedia.org/wiki/Herbal%20distillate
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Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, are aqueous products of hydrodistillation. They are colloidal suspensions of essential oils as well as water-soluble components obtained by steam distillation or hydrodistillation (a variant of steam distillation) from plants and herbs. These herbal distillates have uses as flavorings and cosmetics. Common herbal distillates for skincare include rose water, orange flower water, and witch hazel. Rosemary, oregano, and thyme are hydrosols that may be used in food manufacturing.
Production
Herbal distillates are produced in the same or similar manner as essential oils. However, essential oils will float to the top of the distillate where it is removed, leaving behind the watery distillate. For this reason the term essential water is an apt description. In the past, these essential waters were often considered a byproduct of distillation, but are now considered an important co-product. The produced herbal waters are essentially diluted essential oils at less than 1% concentration (typically 0.02% to 0.05%). Several factors, such as temperature and an herb's growth cycle, impact the characteristics of a distillate, and therefore influence the timing of the distillation. Rosemary, for example, should be distilled in the peak of summer before it flowers.
Usage
Distillates are used as flavorings, cosmetics and as herbal treatments. Herbal distillates are less concentrated than essential oils, possibly making them more suitable for some topical uses.
Science
The science of distillation is based on the fact that different substances vaporise at different temperatures. Unlike other extraction techniques based on solubility of a compound in either water or oil, distillation will separate components regardless of their solubility. The distillate will contain compounds that vaporize at or below the temperature of distillation. The actual chemical components of these
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https://en.wikipedia.org/wiki/Cumulative%20prospect%20theory
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Cumulative prospect theory (CPT) is a model for descriptive decisions under risk and uncertainty which was introduced by Amos Tversky and Daniel Kahneman in 1992 (Tversky, Kahneman, 1992). It is a further development and variant of prospect theory. The difference between this version and the original version of prospect theory is that weighting is applied to the cumulative probability distribution function, as in rank-dependent expected utility theory but not applied to the probabilities of individual outcomes. In 2002, Daniel Kahneman received the Bank of Sweden Prize in Economic Sciences in Memory of Alfred Nobel for his contributions to behavioral economics, in particular the development of Cumulative Prospect Theory (CPT).
Outline of the model
The main observation of CPT (and its predecessor prospect theory) is that people tend to think of possible outcomes usually relative to a certain reference point (often the status quo) rather than to the final status, a phenomenon which is called framing effect. Moreover, they have different risk attitudes towards gains (i.e. outcomes above the reference point) and losses (i.e. outcomes below the reference point) and care generally more about potential losses than potential gains (loss aversion). Finally, people tend to overweight extreme events, but underweight "average" events. The last point is in contrast to Prospect Theory which assumes that people overweight unlikely events, independently of their relative outcomes.
CPT incorporates these observations in a modification of expected utility theory by replacing final wealth with payoffs relative to the reference point, replacing the utility function with a value function that depends on relative payoff, and replacing cumulative probabilities with weighted cumulative probabilities.
In the general case, this leads to the following formula for subjective utility of a risky outcome described by probability measure :
where is the value function (typical form shown in F
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https://en.wikipedia.org/wiki/Cyclotomic%20unit
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In mathematics, a cyclotomic unit (or circular unit) is a unit of an algebraic number field which is the product of numbers of the form (ζ − 1) for ζ an nth root of unity and 0 < a < n.
Properties
The cyclotomic units form a subgroup of finite index in the group of units of a cyclotomic field. The index of this subgroup of real cyclotomic units (those cyclotomic units in the maximal real subfield) within the full real unit group is equal to the class number of the maximal real subfield of the cyclotomic field.
If is the power of a prime, then is not a unit; however the numbers for , and ±ζ generate the group of cyclotomic units.
If is a composite number having two or more distinct prime factors, then is a unit. The subgroup of cyclotomic units generated by with is not of finite index in general.
The cyclotomic units satisfy distribution relations. Let be a rational number prime to and let denote . Then for we have
Using these distribution relations and the symmetry relation a basis Bn of the cyclotomic units can be constructed with the property that for .
See also
Elliptic unit
Modular unit
Notes
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https://en.wikipedia.org/wiki/Guillotine%20partition
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Guillotine partition is the process of partitioning a rectilinear polygon, possibly containing some holes, into rectangles, using only guillotine-cuts. A guillotine-cut (also called an edge-to-edge cut) is a straight bisecting line going from one edge of an existing polygon to the opposite edge, similarly to a paper guillotine.
Guillotine partition is particularly common in designing floorplans in microelectronics. An alternative term for a guillotine-partition in this context is a slicing partition or a slicing floorplan. Guillotine partitions are also the underlying structure of binary space partitions. There are various optimization problems related to guillotine partition, such as: minimizing the number of rectangles or the total length of cuts. These are variants of polygon partitioning problems, where the cuts are constrained to be guillotine cuts.
A related but different problem is guillotine cutting. In that problem, the original sheet is a plain rectangle without holes. The challenge comes from the fact that the dimensions of the small rectangles are fixed in advance. The optimization goals are usually to maximize the area of the produced rectangles or their value, or minimize the waste or the number of required sheets.
Computing a guillotine partition with a smallest edge-length
In the minimum edge-length rectangular-partition problem, the goal is to partition the original rectilinear polygon into rectangles, such that the total edge length is a minimum.
This problem can be solved in time even if the raw polygon has holes. The algorithm uses dynamic programming based on the following observation: there exists a minimum-length guillotine rectangular partition in which every maximal line segment contains a vertex of the boundary. Therefore, in each iteration, there are possible choices for the next guillotine cut, and there are altogether subproblems.
In the special case in which all holes are degenerate (single points), the minimum-length guillotin
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https://en.wikipedia.org/wiki/Intersection%20curve
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In geometry, an intersection curve is a curve that is common to two geometric objects. In the simplest case, the intersection of two non-parallel planes in Euclidean 3-space is a line. In general, an intersection curve consists of the common points of two transversally intersecting surfaces, meaning that at any common point the surface normals are not parallel. This restriction excludes cases where the surfaces are touching or have surface parts in common.
The analytic determination of the intersection curve of two surfaces is easy only in simple cases; for example: a) the intersection of two planes, b) plane section of a quadric (sphere, cylinder, cone, etc.), c) intersection of two quadrics in special cases. For the general case, literature provides algorithms, in order to calculate points of the intersection curve of two surfaces.
Intersection line of two planes
Given: two planes linearly independent, i.e. the planes are not parallel.
Wanted: A parametric representation of the intersection line.
The direction of the line one gets from the crossproduct of the normal vectors: .
A point of the intersection line can be determined by intersecting the given planes with the plane , which is perpendicular to and . Inserting the parametric representation of into the equations of und yields the parameters and .
Example:
The normal vectors are and the direction of the intersection line is . For point , one gets from the formula above Hence
is a parametric representation of the line of intersection.
Remarks:
In special cases, the determination of the intersection line by the Gaussian elimination may be faster.
If one (or both) of the planes is given parametrically by , one gets as normal vector and the equation is: .
Intersection curve of a plane and a quadric
In any case, the intersection curve of a plane and a quadric (sphere, cylinder, cone,...) is a conic section. For details, see. An important application of plane sections of quadrics is conto
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https://en.wikipedia.org/wiki/Robert%20Brown%20%28botanist%2C%20born%201773%29
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Robert Brown (21 December 1773 – 10 June 1858) was a Scottish botanist and paleobotanist who made important contributions to botany largely through his pioneering use of the microscope. His contributions include one of the earliest detailed descriptions of the cell nucleus and cytoplasmic streaming; the observation of Brownian motion; early work on plant pollination and fertilisation, including being the first to recognise the fundamental difference between gymnosperms and angiosperms; and some of the earliest studies in palynology. He also made numerous contributions to plant taxonomy, notably erecting a number of plant families that are still accepted today; and numerous Australian plant genera and species, the fruit of his exploration of that continent with Matthew Flinders.
Early life
Robert Brown
was born in Montrose on 21 December 1773, in a house that existed on the site where Montrose Library currently stands. He was the son of James Brown, a minister in the Scottish Episcopal Church with Jacobite convictions so strong that in 1788 he defied his church's decision to give allegiance to George III. His mother was Helen Brown née Taylor, the daughter of a Presbyterian minister. As a child Brown attended the local Grammar School (now called Montrose Academy), then Marischal College at Aberdeen, but withdrew in his fourth year when the family moved to Edinburgh in 1790. His father died late the following year. He had a friend namely Ishaan lanker who accompanied him with his various researchs.
Brown enrolled to study medicine at the University of Edinburgh, but developed an interest in botany and ended up spending more of his time on the latter than the former. He attended the lectures of John Walker; made botanical expeditions into the Scottish Highlands, alone or with nurserymen such as George Don; and wrote out meticulous botanical descriptions of the plants he collected. He also began corresponding with and collecting for William Withering, one of the f
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https://en.wikipedia.org/wiki/Dewar%20reactivity%20number
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In Hückel theory, a Dewar reactivity number, also known as Dewar number, is a measure of the reactivity in aromatic systems. It is used to quantify the difference in energy between the π-system of the original molecule and the intermediate having the incoming electrophile or nucleophile attached. It can be used to study important transformations such as the nitration of conjugated systems from a theoretical perspective.
The change in energy during the reaction can be derived by allowing the orbitals nearby the site i of attack to interact with the incoming molecule. A secular determinant can be formulated resulting in the equation:
where β is the Huckel interaction parameter and ar and as are the coefficients of the highest energy molecular orbital at nearby sites r and s respectively. Dewar's reactivity number is then defined as .
Clearly, the smaller the value of Ni, the less the destabilization energy in going towards the transition state and the more reactive the site. Thus, by computation of the molecular orbital coefficients it is possible to evaluate Dewar's number for all the sites and establish which one will be the most reactive. This has been shown to correlate well with experimental results.
The method is particularly efficient for alternant hydrocarbons in which the coefficients of the non-bonding orbitals involved are very easy to calculate.
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https://en.wikipedia.org/wiki/Nicolaus%20II%20Bernoulli
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Nicolaus II Bernoulli (also spelled as Niklaus or Nikolaus; 6 February 1695 in Basel – 31 July 1726 in Saint Petersburg) was a Swiss mathematician as were his father Johann Bernoulli and one of his brothers, Daniel Bernoulli. He was one of the many prominent mathematicians in the Bernoulli family.
Work
Nicolaus worked mostly on curves, differential equations, and probability. He was a friend and contemporary of Leonhard Euler, who studied under Nicolaus' father. He also contributed to fluid dynamics.
He was older brother of Daniel Bernoulli, to whom he also taught mathematics. Even in his youth he had learned several languages. From the age of 13, he studied mathematics and law at the University of Basel. In 1711 he received his Master's of Philosophy; in 1715 he received a Doctorate in Law. In 1716-17 he was a private tutor in Venice. From 1719 he had the Chair in Mathematics at the University of Padua, as the successor of Giovanni Poleni. He served as an assistant to his father, among other areas, in the correspondence over the priority dispute between Isaac Newton and Leibniz, and also in the priority dispute between his father and the English mathematician Brook Taylor. In 1720 he posed the problem of reciprocal orthogonal trajectories, which was intended as a challenge for the English Newtonians. From 1723 he was a law professor at the Berner Oberen Schule. In 1725 he together with his brother Daniel, with whom he was touring Italy and France at this time, was invited by Peter the Great to the newly founded St. Petersburg Academy. Eight months after his appointment he came down with a fever and died. His professorship was succeeded in 1727 by Leonhard Euler, whom the Bernoulli brothers had recommended. His early death cut short a promising career.
See also
Bernoulli distribution
Bernoulli process
Bernoulli trial
St. Petersburg paradox
External links
Further reading
1695 births
1726 deaths
Mathematical analysts
Probability theorists
Swiss Calvin
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https://en.wikipedia.org/wiki/Union%20of%20Shop%2C%20Distributive%20and%20Allied%20Workers
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The Union of Shop, Distributive and Allied Workers (Usdaw) is a trade union in the United Kingdom, consisting of over 360,000 members. Usdaw members work in a variety of occupations and industries including: shopworkers, factory and warehouse workers, drivers, call centres, clerical workers, milkround and dairy process, butchers and meat packers, catering, laundries, chemical processing, home shopping and pharmaceutical. The retail sector employs around 2.77 million people.
Usdaw relies upon a "partnership" model with large employers such as with Tesco, where there exists "privileged access" to the management of both organisations. This arrangement coupled with its actions has been met with criticism, such as where the union seemingly presents itself as being concerned more with maintaining its positive, comfortable position and easy membership supply than that of fair representation of its members. This attitude has earned the union the pejorative backronym of Useless Seven Days A Week amongst workers and trade unionists.
It is widely considered to be on the right-wing on the political spectrum, occupying the "politically conservative" section of the Labour Party. Usdaw is also affiliated to the Co-operative Party. In November 2021, the union was criticised at its refusal to negotiate with a Nottingham-based employer who was proposing a 'fire-and-rehire' policy leading to workers having to negotiate for themselves.
Usdaw is campaigning to win a “New Deal for Workers”: A minimum wage that workers can actually live on; secure hours and an end to zero hours contracts; sick pay for everyone, from day one of illness; stronger redundancy rights; fairness, equality and a stronger voice at work. Usdaw’s annual Respect for Shopworkers Week usually takes place mid-November and runs from 14th to 20th in 2022. During the campaign week Usdaw members are raising awareness of the union’s year-round Freedom from Fear Campaign, talking to the public to promote a message of ‘resp
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https://en.wikipedia.org/wiki/Pseudo-ring
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In mathematics, and more specifically in abstract algebra, a pseudo-ring is one of the following variants of a ring:
A rng, i.e., a structure satisfying all the axioms of a ring except for the existence of a multiplicative identity.
A set R with two binary operations + and ⋅ such that is an abelian group with identity 0, and and for all a, b, c in R.
An abelian group equipped with a subgroup B and a multiplication making B a ring and A a B-module.
None of these definitions are equivalent, so it is best to avoid the term "pseudo-ring" or to clarify which meaning is intended.
See also
Semiring – an algebraic structure similar to a ring, but without the requirement that each element must have an additive inverse
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https://en.wikipedia.org/wiki/Tommy%20Gate
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Tommy Gate is an American brand of hydraulic liftgate, or tail lift, manufactured by Woodbine Manufacturing Company. The company was formed in 1965 by Delbert "Bus" Brown and its production facility is located in Woodbine, Iowa.
History
Prior to founding Woodbine Manufacturing Company, Delbert Brown manufactured farming equipment as Brown Manufacturing Company. After inventing what was then one of the first trenching machines, Brown Manufacturing Company was sold to Omaha Steel Works. Three years later, Brown founded Woodbine Manufacturing Company and began the Tommy Gate brand.
Expansion
The Woodbine manufacturing facility was initially built in 1965 to occupy 70,000 square feet of production space. It expanded in 1980 to 90,000 and once again in 2000 when it grew to 140,000. The most recent expansion, completed in 2011, grew the plant to an overall 200,000 square feet (including 40,000 square feet of warehouse space).
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https://en.wikipedia.org/wiki/StaDyn%20%28programming%20language%29
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StaDyn is an object-oriented general-purpose programming language for the .NET platform that supports both static and dynamic typing in the same programming language.
The StaDyn compiler gathers type information for the dynamically typed code. That type information is used to detect type errors at compilation time and to perform significant optimizations. For that purpose, it provides type reconstruction (inference), flow-sensitive types, union and intersection types, constraint-based typing, alias analysis and method specialization.
Its first prototype appeared in 2007, as a modification of C# 3.0. Type inference was supported by including var as a new type, unlike C#, which only offers var to define initialized local variables. Flow-sensitive types of var references are inferred by the compiler, providing type-safe duck typing. When a more lenient approach is required by the programmer, the dynamictype could be used instead of var. Although type inference is still performed, dynamic references behave closer to those in dynamic languages.
StaDyn is designed by Francisco Ortin from the University of Oviedo. The language has been implemented by different members of the Computational Reflection research group, including Miguel Garcia, Jose Baltasar García Perez-Schofield and Jose Quiroga, besides Francisco Ortin.
The name StaDyn is a portmanteau of static and dynamic, denoting its aim to provide the benefits of both static and dynamic typing.
Code samples
Variables with different types
Just like dynamic languages, variables may hold different types in the same scope:
using System;
class Program {
public static void Main() {
Console.Write("Number: ");
var age = Console.In.ReadLine();
Console.WriteLine("Digits: " + age.Length);
age = Convert.ToInt32(age);
age++;
Console.WriteLine("Happy birthday, you are " + age +
" years old now.");
int length = age.Length; // * Compiler er
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https://en.wikipedia.org/wiki/Pollen
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Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophytes during the process of their movement from the stamens to the pistil of flowering plants, or from the male cone to the female cone of gymnosperms. If pollen lands on a compatible pistil or female cone, it germinates, producing a pollen tube that transfers the sperm to the ovule containing the female gametophyte. Individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is highly useful in paleoecology, paleontology, archaeology, and forensics.
Pollen in plants is used for transferring haploid male genetic material from the anther of a single flower to the stigma of another in cross-pollination. In a case of self-pollination, this process takes place from the anther of a flower to the stigma of the same flower.
Pollen is infrequently used as food and food supplement. Because of agricultural practices, it is often contaminated by agricultural pesticides.
Structure and formation
Pollen itself is not the male gamete. It is a gametophyte, something that could be considered an entire organism, which then produces the male gamete. Each pollen grain contains vegetative (non-reproductive) cells (only a single cell in most flowering plants but several in other seed plants) and a generative (reproductive) cell. In flowering plants the vegetative tube cell produces the pollen tube, and the generative cell divides to form the two sperm nuclei.
Pollen comes in many different shapes. Some pollen grains are based on geodesic polyhedra like a soccer ball.
Formation
Pollen is produced in the microsporangia in the male cone of a conifer or other gymnosperm or in the anthers of an angiosperm flower. Pollen g
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https://en.wikipedia.org/wiki/Fader%20creep
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Fader creep is a colloquial term used in audio recording to describe a tendency for sound engineers to raise the gain of individual channels on a mixing console, rather than lowering others to achieve the desired change in the mix.
Results of creeping
As a result, the faders (potentiometers that operate by sliding up or down) or volume controls (rotary potentiometers) on the mixing board or audio processor gradually "creep" toward the maximum volume setting, which reduces the ability to manipulate the relative volumes between channels. It can also result in clipping or distortion of the master mix, which is when the overall volume of sound is too great for the equipment or recording medium intended to hold it.
Multi track problems with creep
Fader creep can be a particular problem in audio mixing sessions for multi-track recordings, where individual sounds held on separate audio tracks, or delivered by outboard MIDI or computer audio equipment are combined into the final stereo presentation of the recording. For example, an engineer might compensate for a particularly loud drum track by raising the volumes of the voice, the guitar, and the piano to the point where all of the individual signals are competing for headroom. A better solution is to lower the volume of the drums, and adjust the other channels accordingly.
Live concert creep
In audio mixing for live concerts, fader creep can result when ear fatigue (the diminishing of the ability for the human ear to hear clearly after prolonged exposure to loud sounds) reduces the ability of the sound engineer to hear the individual components of the mix (i.e. separate instruments and voices on the stage) accurately.
Audio mixing
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https://en.wikipedia.org/wiki/Banks%E2%80%93Zaks%20fixed%20point
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In quantum chromodynamics (and also N = 1 super quantum chromodynamics) with massless flavors, if the number of flavors, Nf, is sufficiently small (i.e. small enough to guarantee asymptotic freedom, depending on the number of colors), the theory can flow to an interacting conformal fixed point of the renormalization group. If the value of the coupling at that point is less than one (i.e. one can perform perturbation theory in weak coupling), then the fixed point is called a Banks–Zaks fixed point. The existence of the fixed point was first reported in 1974 by Belavin and Migdal and by Caswell, and later used by Banks and Zaks in their analysis of the phase structure of vector-like gauge theories with massless fermions. The name Caswell–Banks–Zaks fixed point is also used.
More specifically, suppose that we find that the beta function of a theory up to two loops has the form
where and are positive constants. Then there exists a value such that :
If we can arrange to be smaller than , then we have . It follows that when the theory flows to the IR it is a conformal, weakly coupled theory with coupling .
For the case of a non-Abelian gauge theory with gauge group and Dirac fermions in the fundamental representation of the gauge group for the flavored particles we have
where is the number of colors and the number of flavors. Then should lie just below in order for the Banks–Zaks fixed point to appear. Note that this fixed point only occurs if, in addition to the previous requirement on (which guarantees asymptotic freedom),
where the lower bound comes from requiring . This way remains positive while is still negative (see first equation in article) and one can solve with real solutions for . The coefficient was first correctly computed by Caswell, while the earlier paper by Belavin and Migdal has a wrong answer.
See also
Beta function
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https://en.wikipedia.org/wiki/Lira%20512
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Lira 512 (also known as Lira XT) was an IBM PC XT compatible computer made by the Yugoslav (now Serbian) company EI Niš in the late 1980s. It was first presented to the public in April 1988 at the “Kompjuter ‘88” computer show in Belgrade. Soon after that, Lira 512 was also presented in Yugoslav computer press.
What separates Lira 512 from most of the other XT compatibles is that keyboard is included just above in the same case (together with the 3.5’’ floppy drive), which made it similar in appearance to the original Atari ST or the Amiga 500. Lira has two display adapters (monochrome Hercules compatible and color CGA compatible), where the active video adapter is chosen by the back-panel switch. A 40W power adapter is also installed in the same case.
The main purpose of Lira 512 was to be used in computer classrooms.
Specifications
CPU: Intel 8088 running at 4.77 MHz or 10 MHz (turbo)
ROM: 8 KB Award BIOS, expandable to 32KB
RAM: 512 KB (expandable up to 640 KB)
Operating system: MS DOS 3.21
Secondary storage: 3.5’’ Panasonic floppy drive 720KB
Display: two display adapters (only one can be used at a time)
Hercules compatible adapter (monochrome 80x25 text or graphic 720x348)
CGA compatible adapter (color text 40x25, 80x25 or graphic 320x200, 640x200)
Sound: beeper
I/O ports: composite, RF and DE9 RGB video output, RS-232 (DB25 male + DE9 male connector reserved for the mouse), parallel port (DB25 female connector), external floppy connector, DA15 PC joystick female connector, light pen and expansion connector
Power supply 40W
Lira 512 gallery
Other Lira models
Lira XT Tower
Lira XT Tower was released about a year after the release of the original Lira 512, because it was realized that 512's compact case limits hardware expansion. To address this issue, especially to allow for the installation of the hard disk, the case was changed to a slimline tower.
Lira AT
About the same time with Lira XT Tower, the new Lira AT was released with similar loo
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https://en.wikipedia.org/wiki/Parallax%20SX
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Parallax SX is a discontinued line of microcontrollers that was marketed by Parallax, from a design by Ubicom. Designed to be architecturally similar to the PIC microcontrollers used in the original versions of the BASIC Stamp, SX microcontrollers replaced the PIC in several subsequent versions of that product.
Production
The designs for the devices are owned by Ubicom (formerly Scenix, hence "SX"). The SX dies were manufactured by Ubicom, who sent them to Parallax for packaging. Ubicom had made processors with 18, 20, 28, 48 and 52 pins, but because Parallax did not have packages for 18 and 52 pins chips, the SX-18 and SX-52 were discontinued.
End-of-life
On July 31, 2009, Parallax announced that the SX line had reached its production EOL (End-of-Life) as Ubicom would no longer be manufacturing dies based on the designs; after the supplies from the final "lifetime buy" have been exhausted, the associated products cannot be restocked. In the same announcement, Parallax expressed that availability of its own products based on SX devices would not be impacted and that technical support would remain available.
Technical details
The Parallax's SX series microcontrollers are 8-bit RISC microcontrollers (using a 12-bit instruction word) which have an unusually high speed, up to 75 MHz (75 MIPS), and a high degree of flexibility. They include up to 4096 12-bit words of Flash memory and up to 262 bytes of random-access memory (RAM), an eight bit counter and other support logic. They are especially geared toward the emulation of I/O hardware in software, which makes them very flexible. While Parallax's SX micros are limited in variety, their high speed and additional resources allow programmers to create 'virtual devices', including complete video controllers, as required. For example, there are software library modules to emulate I2C and SPI interfaces, UARTs, frequency generators, measurement counters and PWM and sigma-delta A/D converters. Other interfaces are relat
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https://en.wikipedia.org/wiki/Hiroshima%20%28song%29
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"Hiroshima" is an anti-war song performed by British band Wishful Thinking, written by David Morgan and produced by Lou Reizner, which tells about the atomic bombing of Hiroshima. The track was recorded at the Chappell Recording Studios in London in 1970. It was first released in 1971 as a single from their album of the same name, but achieved commercial success only upon its re-release in 1978, when it peaked at 8 in West Germany, staying on the chart for 44 weeks. It was one of the best-selling singles of 1978 in West Germany.
Track listing
7-inch single
A. "Hiroshima" – 4:42
B. "She Belongs to the Night" – 2:47
Charts
Weekly charts
Year-end charts
Sandra version
German singer Sandra covered "Hiroshima" and released her version as a single in January 1990, with production by Michael Cretu. Sandra decided to cover the anti-war "Hiroshima" out of her concern about the political unrest happening in countries like Lebanon, China and Romania in the late 1980s. It was the first song recorded for her fourth album Paintings in Yellow and was released as the LP's lead single in February 1990.
Sandra's cover was commercially successful, particularly in Germany and Switzerland, where it reached the top five and remains one of Sandra's highest-charting singles. In Switzerland, it also peaked at No. 11 on the airplay chart. The music video for the song was directed by Roland Willaert. The clip was released on Sandra's VHS video compilation 18 Greatest Hits in 1992 and the 2003 DVD The Complete History.
In 1999, a remix of the song was released on Sandra's compilation My Favourites. The track was remixed again for her 2006 compilation Reflections.
Critical reception
Music & Media wrote, "A slow, moody number that is spoilt by the obviousness of the production but is, in fact, a charming song with a fine melody."
Track listings
7-inch single
A. "Hiroshima" – 4:11
B. "La vista de luna" – 3:44
12-inch single
A. "Hiroshima" (extended version) – 6:44
B1. "Hiroshima" (
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https://en.wikipedia.org/wiki/Neural%20tube%20defect
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Neural tube defects (NTDs) are a group of birth defects in which an opening in the spine or cranium remains from early in human development. In the third week of pregnancy called gastrulation, specialized cells on the dorsal side of the embryo begin to change shape and form the neural tube. When the neural tube does not close completely, an NTD develops.
Specific types include: spina bifida which affects the spine, anencephaly which results in little to no brain, encephalocele which affects the skull, and iniencephaly which results in severe neck problems.
NTDs are one of the most common birth defects, affecting over 300,000 births each year worldwide. For example, spina bifida affects approximately 1,500 births annually in the United States, or about 3.5 in every 10,000 (0.035% of US births), which has decreased from around 5 per 10,000 (0.05% of US births) since folate fortification of grain products was started. The number of deaths in the US each year due to neural tube defects also declined from 1,200 before folate fortification was started to 840.
Types
There are two classes of NTDs: open, which are more common, and closed. Open NTDs occur when the brain and/or spinal cord are exposed at birth through a defect in the skull or vertebrae (spinal column). Open NTDs include anencephaly, encephaloceles, hydranencephaly, iniencephaly, schizencephaly, and the most common form, spina bifida. Closed NTDs occur when the spinal defect is covered by skin. Types of closed NTDs include lipomeningocele, lipomyelomeningocele, and tethered cord.
Anencephaly
Anencephaly (without brain) is a severe neural tube defect that occurs when the anterior-most end of the neural tube fails to close, usually during the 23rd and 26th days of pregnancy. This results in an absence of a major portion of the brain and skull. Infants born with this condition lack the main part of the forebrain and are usually blind, deaf and display major craniofacial anomalies. The lack of a functioning ce
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https://en.wikipedia.org/wiki/Ionotropic%20glutamate%20receptor
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Ionotropic glutamate receptors (iGluRs) are ligand-gated ion channels that are activated by the neurotransmitter glutamate. They mediate the majority of excitatory synaptic transmission throughout the central nervous system and are key players in synaptic plasticity, which is important for learning and memory. iGluRs have been divided into four subtypes on the basis of their ligand binding properties (pharmacology) and sequence similarity: AMPA receptors, kainate receptors, NMDA receptors and delta receptors (see below).
AMPA receptors are the main charge carriers during basal transmission, permitting influx of sodium ions to depolarise the postsynaptic membrane. NMDA receptors are blocked by magnesium ions and therefore only permit ion flux following prior depolarisation. This enables them to act as coincidence detectors for synaptic plasticity. Calcium influx through NMDA receptors leads to persistent modifications in the strength of synaptic transmission.
iGluRs are tetramers (they are formed of four subunits). All subunits have a shared architecture with four domain layers: two extracellular clamshell domains called the N-terminal domain (NTD) and ligand-binding domain (LBD; which binds glutamate), the transmembrane domain (TMD) that forms the ion channel, and an intracellular C-terminal domain (CTD).
Human proteins/genes encoding iGluR subunits
AMPA receptors: GluA1/GRIA1; GluA2/GRIA2; GluA3/GRIA3; GluA4/GRIA4;
delta receptors: GluD1/GRID1; GluD2/GRID2;
kainate receptors: GluK1/GRIK1; GluK2/GRIK2; GluK3/GRIK3; GluK4/GRIK4; GluK5/GRIK5;
NMDA receptors: GluN1/GRIN1; GluN2A/GRIN2A; GluN2B/GRIN2B; GluN2C/GRIN2C; GluN2D/GRIN2D; GluN3A/GRIN3A; GluN3B/GRIN3B;
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https://en.wikipedia.org/wiki/CenterPOS%20Malware
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CenterPOS (also known as "Cerebrus") is a point of sale (POS) malware discovered Cyber Security Experts. It was discovered in September 2015 along with other kinds of POS malware, such as NewPOSThings, BlackPOS, and Alina. There are two versions which have been released by the developer responsible: version 1.7 and version 2.0. CenterPOS 2.0 has similar functionality to CenterPOS version 1.7. The 2.0 variant of CenterPOS malware added some more effective features, such as the addition of a configuration file for storing information in its command and control server.
Overview
CenterPOS has been used to target retailers in order to illegally obtain payment card information using a memory scraper. It uses two distinct modes to scrape and store information: a "smart scan" and a "normal scan". At the normal scan mode, the malware looks at all of the processes on a device and determines which ones are not currently running processes, are not named "system", "system idle process" or "idle", and do not contain keywords such as Microsoft or Mozilla. If the process meets the criteria list, the malware will search all memory regions within the process, searching for credit card data with regular expressions in the regular expression list. In smart scan mode, the malware starts by performing a normal scan, and any process that has a regular expression match will be added to the smart scan list. After the first pass, the malware will only search the processes that are in the smart scan list. The malware contains functionality that allows cybercriminals to create a configuration file.
Process Details
CenterPOS malware searches for the configuration file that contains the C&C information. If unable to find the configuration file, it asks for a password. If the password entered is correct, then it payloads the functions to create a configuration file. This malware is very different from other point of sale system malware in that it has a separate component called builder to cre
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