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https://en.wikipedia.org/wiki/List%20of%20Greek%20flags | This is a list of flags used in the modern state of Greece or historically used by Greeks.
National flag
Presidential standard
Royal standards
Military flags
Hellenic Armed Forces
Hellenic Army
Hellenic Navy
Hellenic Air Force
Hellenic Coast Guard
Regional and municipal flags
Historical flags
Other historical flags
Current and historical variants used outside of Greece
Political flags
Religious flags
Ethnic group flags (used unofficially)
Yacht clubs of Greece
See also
List of Cypriot flags
Flag of Greece |
https://en.wikipedia.org/wiki/Ordnance%20datum | An ordnance datum or OD is a vertical datum used by an ordnance survey as the basis for deriving altitudes on maps. A spot height may be expressed as AOD for "above ordnance datum". Usually mean sea level (MSL) at a particular place is used for the datum. In particular:
In Great Britain, OD for the Ordnance Survey is ODN (Ordnance Datum Newlyn), defined as the MSL as recorded by the Newlyn Tidal Observatory between 1915 and 1921.
Prior to 1921, OD was defined as MSL as recorded in the Victoria Dock, Liverpool, during a short period in 1844 (ODL).
In Northern Ireland, OD for the Ordnance Survey of Northern Ireland is Belfast Ordnance Datum, the MSL at Clarendon Dock, Belfast, between 1951 and 1956.
In Ireland, OD for the Ordnance Survey of Ireland is Malin Ordnance Datum: the MSL at Portmoor Pier, Malin Head, County Donegal, between 1960 and 1969.
Prior to 1970, Poolbeg Ordnance Datum was used: the low water of spring tide at Poolbeg Lighthouse, Dublin, on 8 April 1837. Poolbeg OD was about lower than Malin OD.
Ordnance Datum Newlyn and its antecedents
The First Geodetic Levelling of England and Wales (1840–1860) needed to define a datum plane from which to specify spot heights. At first it was specified as a horizontal plane 100 feet below an arbitrary benchmark on St John's Church, Liverpool. Subsequently, however, it was redefined as mean sea level (MSL). To establish MSL, tidal observations were taken at the Victoria Dock, Liverpool, over a short period in 1844.
By the time of the Second Geodetic Levelling (1912–1921) the importance of stability was better appreciated and so it was decided to use Fundamental Bench Marks (FBMs) installed in solid rock, rather than on buildings as before. To measure average MSL around Great Britain three tide gauges were employed: at Dunbar, Newlyn and Felixstowe. However, it was found that the measured difference between the Dunbar and Newlyn stations was 0.81 feet (0.247m), far larger than could be accounted for by |
https://en.wikipedia.org/wiki/Tinplate | Tinplate consists of sheets of steel coated with a thin layer of tin to impede rusting. Before the advent of cheap milled steel, the backing metal was wrought iron. While once more widely used, the primary use of tinplate now is the manufacture of tin cans.
Tinplate is made by rolling the steel (or formerly iron) in a rolling mill, removing any mill scale by pickling it in acid and then coating it with a thin layer of tin. Plates were once produced individually (or in small groups) in what became known as a pack mill. In the late 1920s pack mills began to be replaced by strip mills which produced larger quantities more economically.
Formerly, tinplate was used for tin ceiling, and holloware (cheap pots and pans), also known as tinware. The people who made tinware (metal spinning) were tinplate workers.
For many purposes, tinplate has been replaced by galvanised (zinc-coated or tinned) vessels, though not for cooking as zinc is poisonous. The zinc layer prevents the iron from rusting through sacrificial protection with the zinc oxidizing instead of the iron, whereas tin will only protect the iron if the tin-surface remains unbroken.
History of production processes and markets
The practice of tin mining likely began circa 3000 B.C. in Western Asia, British Isles and Europe. Tin was an essential ingredient of bronze production during the Bronze Age.
The practice of tinning ironware to protect it against rust is an ancient one. This may have been the work of the whitesmith. This was done after the article was fabricated, whereas tinplate was tinned before fabrication. Tinplate was apparently produced in the 1620s at a mill of (or under the patronage of) the Earl of Southampton, but it is not clear how long this continued.
The first production of tinplate was probably in Bohemia, from where the trade spread to Saxony, and was well-established there by the 1660s. Andrew Yarranton and Ambrose Crowley (a Stourbridge blacksmith and father of the more famous Sir Ambros |
https://en.wikipedia.org/wiki/Overhead%20%28computing%29 | In computer science, overhead is any combination of excess or indirect computation time, memory, bandwidth, or other resources that are required to perform a specific task. It is a special case of engineering overhead. Overhead can be a deciding factor in software design, with regard to structure, error correction, and feature inclusion. Examples of computing overhead may be found in Object Oriented Programming (OOP), functional programming, data transfer, and data structures.
Software design
Choice of implementation
A programmer/software engineer may have a choice of several algorithms, encodings, data types or data structures, each of which have known characteristics. When choosing among them, their respective overhead should also be considered.
Tradeoffs
In software engineering, overhead can influence the decision whether or not to include features in new products, or indeed whether to fix bugs. A feature that has a high overhead may not be included – or needs a big financial incentive to do so. Often, even though software providers are well aware of bugs in their products, the payoff of fixing them is not worth the reward, because of the overhead.
For example, an implicit data structure or succinct data structure may provide low space overhead, but at the cost of slow performance (space/time tradeoff).
Run-time complexity of software
Algorithmic complexity is generally specified using Big O notation. This makes no comment on how long something takes to run or how much memory it uses, but how its increase depends on the size of the input. Overhead is deliberately not part of this calculation, since it varies from one machine to another, whereas the fundamental running time of an algorithm does not.
This should be contrasted with algorithmic efficiency, which takes into account all kinds of resources – a combination (though not a trivial one) of complexity and overhead.
Examples
Computer programming (run-time and computational overhead)
Invoking a function |
https://en.wikipedia.org/wiki/Gray%20graph | In the mathematical field of graph theory, the Gray graph is an undirected bipartite graph with 54 vertices and 81 edges. It is a cubic graph: every vertex touches exactly three edges. It was discovered by Marion C. Gray in 1932 (unpublished), then discovered independently by Bouwer 1968 in reply to a question posed by Jon Folkman 1967. The Gray graph is interesting as the first known example of a cubic graph having the algebraic property of being edge but not vertex transitive (see below).
The Gray graph has chromatic number 2, chromatic index 3, radius 6 and diameter 6. It is also a 3-vertex-connected and 3-edge-connected non-planar graph.
Construction
The Gray graph can be constructed from the 27 points of a 3 × 3 × 3 grid and the 27 axis-parallel lines through these points. This collection of points and lines forms a projective configuration: each point has exactly three lines through it, and each line has exactly three points on it. The Gray graph is the Levi graph of this configuration; it has a vertex for every point and every line of the configuration, and an edge for every pair of a point and a line that touch each other. This construction generalizes (Bouwer 1972) to any dimension n ≥ 3, yielding an n-valent Levi graph with algebraic properties similar to those of the Gray graph. In (Monson, Pisanski, Schulte, Ivic-Weiss 2007), the Gray graph appears as a different sort of Levi graph for the edges and triangular faces of a certain locally toroidal abstract regular 4-polytope. It is therefore the first in an infinite family of similarly constructed cubic graphs. As with other Levi graphs, it is a bipartite graph, with the vertices corresponding to points on one side of the bipartition and the vertices corresponding to lines on the other side.
Marušič and Pisanski (2000) give several alternative methods of constructing the Gray graph. As with any bipartite graph, there are no odd-length cycles, and there are also no cycles of four or six vertices, so th |
https://en.wikipedia.org/wiki/Geothermal%20gradient | Geothermal gradient is the rate of change in temperature with respect to increasing depth in Earth's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises in about 25–30 °C/km (72–87 °F/mi) of depth near the surface in most of the world. However, in some cases the temperature may drop with increasing depth, especially near the surface, a phenomenon known as or geothermal gradient. The effects of weather, the Sun, and season only reach a depth of roughly .
Strictly speaking, geo-thermal necessarily refers to Earth, but the concept may be applied to other planets. In SI units, the geothermal gradient is expressed as °C/km, K/km, or mK/m. These are all equivalent.
Earth's internal heat comes from a combination of residual heat from planetary accretion, heat produced through radioactive decay, latent heat from core crystallization, and possibly heat from other sources. The major heat-producing nuclides in Earth are potassium-40, uranium-238, uranium-235, and thorium-232. The inner core is thought to have temperatures in the range of 4000 to 7000 K, and the pressure at the centre of the planet is thought to be about 360 GPa (3.6 million atm). (The exact value depends on the density profile in Earth.) Because much of the heat is provided for by radioactive decay, scientists believe that early in Earth's history, before nuclides with short half-lives had been depleted, Earth's heat production would have been much higher. Heat production was twice that of present-day at approximately 3 billion years ago, resulting in larger temperature gradients within Earth, larger rates of mantle convection and plate tectonics, allowing the production of igneous rocks such as komatiites that are no longer formed.
The top of the geothermal gradient is influenced by atmospheric temperature. The uppermost layers of the solid planet are at the temperature produced by the |
https://en.wikipedia.org/wiki/Perylene | Perylene or perilene is a polycyclic aromatic hydrocarbon with the chemical formula C20H12, occurring as a brown solid. It or its derivatives may be carcinogenic, and it is considered to be a hazardous pollutant. In cell membrane cytochemistry, perylene is used as a fluorescent lipid probe. It is the parent compound of a class of rylene dyes.
Reactions
Like other polycyclic aromatic compounds, perylene is reduced by alkali metals to give a deeply colored radical anion and a dianion. The diglyme solvates of these salts have been characterized by X-ray crystallography.
Emission
Perylene displays blue fluorescence. It is used as a blue-emitting dopant material in OLEDs, either pure or substituted. Perylene can be also used as an organic photoconductor. It has an absorption maximum at 434 nm, and as with all polycyclic aromatic compounds, low water solubility (1.2 x 10−5 mmol/L). Perylene has a molar absorptivity of 38,500 M−1cm−1 at 435.7 nm.
Structure
The perylene molecule consists of two naphthalene molecules connected by a carbon-carbon bond at the 1 and 8 positions on both molecules. All of the carbon atoms in perylene are sp2 hybridized. The structure of perylene has been extensively studied by X-ray crystallography.
Biology
Naturally occurring perylene quinones have been identified in lichens Laurera sanguinaria Malme and Graphis haematites Fée. |
https://en.wikipedia.org/wiki/Prova | Prova is an open source programming language that combines Prolog with Java.
Description
Prova is a rule-based scripting system that is used for middleware. The language combines imperative and declarative programming by using a prolog syntax that allows calls to Java functions. In this way a strong Java code base is combined with Prolog features such as backtracking.
Prova is derived from Mandarax, a Java-based inference system developed by Jens Dietrich. Prova extends Mandarax by providing a proper language syntax, native syntax integration with Java, agent messaging and reaction rules. The development of this language was supported by the grant provided within the EU projects GeneStream and BioGRID. In the project, the language is used as a rule-based backbone for distributed web applications in biomedical data integration, in particular, the GoPubMed system.
The design goals of Prova:
Combine declarative and object-oriented programming.
Expose logic and agent behavior as rules.
Access data sources via wrappers written in Java or command-line shells like Perl.
Make the Java API of various packages accessible as rules.
Run within the Java runtime.
Enable rapid prototyping of applications.
Offer a rule-based platform for distributed agent programming.
Prova aims to provide support for data integration tasks when the following is important:
Location transparency (local, remote, mirrors);
Format transparency (database, RDF, XML, HTML, flat files, computation resource);
Resilience to change (databases and web sites change often);
Use of open and open source technologies;
Understandability and modifiability by a non-IT specialist;
Economical knowledge representation;
Extensibility with additional functionality;
Leveraging ontologies.
Prova has been used as the key service integration engine in the Xcalia product where it is used for computing efficient global execution plans across multiple data sources such as Web services, TP monitors transactio |
https://en.wikipedia.org/wiki/TV-out | The term TV-out is commonly used to label the connector of equipment providing an analog video signal acceptable for a television AV input. TV-out is different from AV-out in that it only provides video, no audio.
Types of signals and their respective connectors include:
Composite video
S-video
Component video
See AV input for more information.
Television technology
Graphics cards |
https://en.wikipedia.org/wiki/Carrion%20%28comics%29 | Carrion is a fictional character, a supervillain appearing in American comic books published by Marvel Comics. The character is usually depicted as an enemy of Spider-Man.
Publication history
The Miles Warren clone version of Carrion first appeared in The Spectacular Spider-Man #25 and was created by Bill Mantlo, Jim Mooney, and Frank Springer. Carrion emerged as part of a storyline that was a sequel to the original Clone Saga and as a result he has one of the most complicated histories of any Spider-Man villain.
According to Tony Isabella, in Mantlo's original plans for this story, Carrion would have been revealed as the Peter Parker clone. That the real Spider-Man had also dumped the then-deceased Green Goblin's gear in the same furnace explained the Goblin-esque look of Carrion. However, Marv Wolfman, then writer of The Amazing Spider-Man book, had some second thoughts about it. He decided he didn't want a second Spider-Man running around so Bill was asked to change the planned revelation of his extended story, even though the first chapter had already been published.
The character's history has been retconned several times as successive writers changed the status of the various clones, the plans and motivations of Professor Miles Warren and other aspects from the stories. Often these changes took place in stories which did not directly involve Carrion, resulting in further stories trying to tie up gaps. No fewer than three separate incarnations have been encountered.
William Allen first appeared in Spider-Man: Dead Man's Hand #1 (April 1997), created by Roger Stern and Dan Lawlis. McBride was created by Sal Buscema and Gerry Conway in The Spectacular Spider-Man #149 (April 1989).
Fictional character biography
Miles Warren clone
The original Carrion first appeared seeking to destroy Spider-Man, somehow knowing that his secret identity was Peter Parker. He unsuccessfully approached the Maggia with a plan to kill Spider-Man. He attacked Peter Parker, blamin |
https://en.wikipedia.org/wiki/Crypto%20API%20%28Linux%29 | Crypto API is a cryptography framework in the Linux kernel, for various parts of the kernel that deal with cryptography, such as IPsec and dm-crypt. It was introduced in kernel version 2.5.45 and has since expanded to include essentially all popular block ciphers and hash functions.
Userspace interfaces
Many platforms that provide hardware acceleration of AES encryption expose this to programs through an extension of the instruction set architecture (ISA) of the various chipsets (e.g. AES instruction set for x86). With this sort of implementation any program (kernel-mode or user-space) may utilize these features directly.
Some platforms, such as the ARM Kirkwood SheevaPlug and AMD Geode processors, however, are not implemented as ISA extensions, and are only accessible through kernel-mode drivers. In order for user-mode applications that utilize encryption, such as wolfSSL, OpenSSL or GnuTLS, to take advantage of such acceleration, they must interface with the kernel.
AF_ALG
A netlink-based interface that adds an AF_ALG address family; it was merged into version 2.6.38 of the Linux kernel mainline. There was once a plugin to OpenSSL to support AF_ALG, which has been submitted for merging. In version 1.1.0, OpenSSL landed another patch for AF_ALG contributed by Intel. wolfSSL can make use of AF_ALG and
cryptodev
The OpenBSD Cryptographic Framework /dev/crypto interface of OpenBSD was ported to Linux, but never merged.
See also
Microsoft CryptoAPI |
https://en.wikipedia.org/wiki/Aura%20%28symptom%29 | An aura is a perceptual disturbance experienced by some with epilepsy or migraine. An epileptic aura is a seizure.
Epileptic and migraine auras are due to the involvement of specific areas of the brain, which are those that determine the symptoms of the aura. Therefore, if the visual area is affected, the aura will consist of visual symptoms, while if a sensory one, then sensory symptoms will occur.
Epileptic auras are subjective sensory or psychic phenomena due to a focal seizure, i.e. a seizure that originates from that area of the brain responsible for the function which then expresses itself with the symptoms of the aura. It is important because it makes it clear where the alteration causing the seizure is located. An epileptic aura is in most cases followed by other manifestations of a seizure, for example a convulsion, since the epileptic discharge spreads to other parts of the brain. Rarely it remains isolated. Auras, when they occur, allow some people who have epilepsy time to prevent injury to themselves and/or others when they lose consciousness.
Migraine
The aura of migraine is visual in the vast majority of cases, because dysfunction starts from the visual cortex. The aura is usually followed, after a time varying from minutes to an hour, by the migraine headache. However, the migraine aura can manifest itself in isolation, that is, without being followed by headache. The aura can stay for the duration of the migraine; depending on the type of aura, it can leave the person disoriented and confused. It is common for people with migraines to experience more than one type of aura during the migraine. Most people who have auras have the same type of aura every time.
Auras can also be confused with sudden onset of panic, panic attacks or anxiety attacks, which creates difficulties in diagnosis. The differential diagnosis of patients who experience symptoms of paresthesias, derealization, dizziness, chest pain, tremors, and palpitations can be quite chall |
https://en.wikipedia.org/wiki/Systematized%20Nomenclature%20of%20Medicine | The Systematized Nomenclature of Medicine (SNOMED) is a systematic, computer-processable collection of medical terms, in human and veterinary medicine, to provide codes, terms, synonyms and definitions which cover anatomy, diseases, findings, procedures, microorganisms, substances, etc. It allows a consistent way to index, store, retrieve, and aggregate medical data across specialties and sites of care. Although now international, SNOMED was started in the U.S. by the College of American Pathologists (CAP) in 1973 and revised into the 1990s. In 2002 CAP's SNOMED Reference Terminology (SNOMED RT) was merged with, and expanded by, the National Health Service's Clinical Terms Version 3 (previously known as the Read codes) to produce SNOMED CT.
Versions of SNOMED released prior to 2001 were based on a multiaxial, hierarchical classification system. As in any such system, a disease may be located in a body organ (anatomy), which results in a code in a topography axis and may lead to morphological alterations represented by a morphology code.
In 2002 the first release of SNOMED CT adopted a completely different structure. A sub-type hierarchy, supported by defining relationships based on description logic, replaced the axes described in this article. Versions of SNOMED prior to SNOMED CT are planned to be formally deprecated from 2017. Therefore, readers interested in current information about SNOMED are directed to the article on SNOMED CT.
Purpose
SNOMED was designed as a comprehensive nomenclature of clinical medicine for the purpose of accurately storing and/or retrieving records of clinical care in human and veterinary medicine.
The metaphor used by Roger A. Côté, the first editorial chair, was that SNOMED would become the periodic table of elements of medicine because of its definitional organization beyond the hierarchical design. Indeed, diseases and procedures were ordered hierarchically and are further referenced back to more elementary terms (see Reference |
https://en.wikipedia.org/wiki/Morquio%20syndrome | Morquio syndrome, also known as mucopolysaccharidosis type IV (MPS IV), is a rare metabolic disorder in which the body cannot process certain types of sugar molecules called glycosaminoglycans (AKA GAGs, or mucopolysaccharides). In Morquio syndrome, the specific GAG which builds up in the body is called keratan sulfate. This birth defect, which is autosomal recessive, is a type of lysosomal storage disorder. The buildup of GAGs in different parts of the body causes symptoms in many different organ systems. In the US, the incidence rate for Morquio syndrome is estimated at between 1 in 200,000 and 1 in 300,000 live births.
Signs and symptoms
Patients with Morquio syndrome appear healthy at birth. Types A and B have similar presentations, but Type B generally has milder symptoms. The age of onset is usually between 1 and 3 years of age. Morquio syndrome causes progressive changes to the skeleton of the ribs and chest, which may lead to neurological complications such as nerve compression. Patients may also have hearing loss and clouded corneas. Intelligence is usually normal unless a patient has untreated hydrocephalus.
Physical growth slows and often stops around age 8. Skeletal abnormalities include a bell-shaped chest, a flattening or curvature of the spine, shortened long bones, and dysplasia of the hips, knees, ankles, and wrists. The bones that stabilize the connection between the head and neck can be malformed (odontoid hypoplasia); in these cases, a surgical procedure called spinal cervical bone fusion can be lifesaving. Restricted breathing, joint stiffness, and heart disease are also common. Children with the more severe form of MPS IV may not live beyond their twenties or thirties.
Some additional signs and symptoms of Morquio syndrome include a short stature, scoliosis, kyphosis, hypermobile joints, knock-knees, pectus carinatum, misshapen limbs, unstable vertebrae, cord compression, hepatomegaly, hearing problems, vision problems, and heart problems. |
https://en.wikipedia.org/wiki/Paul%20Bernays | Paul Isaac Bernays (17 October 1888 – 18 September 1977) was a Swiss mathematician who made significant contributions to mathematical logic, axiomatic set theory, and the philosophy of mathematics. He was an assistant and close collaborator of David Hilbert.
Biography
Bernays was born into a distinguished German-Jewish family of scholars and businessmen. His great-grandfather, Isaac ben Jacob Bernays, served as chief rabbi of Hamburg from 1821 to 1849.
Bernays spent his childhood in Berlin, and attended the Köllner Gymnasium, 1895–1907. At the University of Berlin, he studied mathematics under Issai Schur, Edmund Landau, Ferdinand Georg Frobenius, and Friedrich Schottky; philosophy under Alois Riehl, Carl Stumpf and Ernst Cassirer; and physics under Max Planck. At the University of Göttingen, he studied mathematics under David Hilbert, Edmund Landau, Hermann Weyl, and Felix Klein; physics under Voigt and Max Born; and philosophy under Leonard Nelson.
In 1912, the University of Berlin awarded him a Ph.D. in mathematics for a thesis, supervised by Landau, on the analytic number theory of binary quadratic forms. That same year, the University of Zurich awarded him habilitation for a thesis on complex analysis and Picard's theorem. The examiner was Ernst Zermelo. Bernays was Privatdozent at the University of Zurich, 1912–17, where he came to know George Pólya. His collected communications with Kurt Gödel span many decades.
Starting in 1917, David Hilbert employed Bernays to assist him with his investigations of the foundation of arithmetic. Bernays also lectured on other areas of mathematics at the University of Göttingen. In 1918, that university awarded him a second habilitation for a thesis on the axiomatics of the propositional calculus of Principia Mathematica.
In 1922, Göttingen appointed Bernays extraordinary professor without tenure. His most successful student there was Gerhard Gentzen. After Nazi Germany enacted the Law for the Restoration of the Professi |
https://en.wikipedia.org/wiki/Kellas%20cat | The Kellas cat is a large black cat found in Scotland. It is an interspecific hybrid between the Scottish wildcat (Felis silvestris silvestris syn. Felis silvestris grampia) and the domestic cat (Felis catus). Once thought to be a mythological wild cat, with its few sightings dismissed as hoaxes, a specimen was killed in a snare by a gamekeeper in 1984 and found to be a hybrid between the Scottish wildcat and domestic cat. It is not a formal cat breed, but a landrace of felid hybrids. It is named after the village of Kellas, Moray, where it was first found. The purported first live cat was caught by the Tomorrows World team and featured in the 1986 programme 'On the Trail of the Big Cat'. The historian Charles Thomas speculated that the Pictish stone at Golspie may depict a Kellas cat. The Golspie stone, now held at the Dunrobin Castle Museum, shows a cat-like creature standing on top of a salmon which may allude to the characteristics ascribed to a Kellas cat of catching fish while swimming in the river.
A researcher at the National Museum of Scotland examined eight Kellas cat specimens. One carcass was already in the Museum's collection; the remaining seven were supplied by Di Francis, who is described by Thomas as a "writer, researcher and practical naturalist". He identified one of the animals as a melanistic wildcat; this juvenile male was the first wildcat ever documented as melanistic in Scotland. Most of the other specimens examined were concluded to be hybrids but more closely aligned to the Scottish wildcat; only one hybrid leaned more towards a domestic cat.
The Kellas cat is described as being long, with powerful and long hind legs and a tail that can grow to be around long; its weight ranges from . The animal snared in 1984 was to shoulder height and measured from nose to tail. A specimen is kept in a museum in Elgin. The Zoology Museum of the University of Aberdeen also holds a mounted specimen that was found during 2002 in the Insch area of Aber |
https://en.wikipedia.org/wiki/Sherman%E2%80%93Morrison%20formula | In mathematics, in particular linear algebra, the Sherman–Morrison formula, named after Jack Sherman and Winifred J. Morrison, computes the inverse of the sum of an invertible matrix and the outer product, , of vectors and . The Sherman–Morrison formula is a special case of the Woodbury formula. Though named after Sherman and Morrison, it appeared already in earlier publications.
Statement
Suppose is an invertible square matrix and are column vectors. Then is invertible iff . In this case,
Here, is the outer product of two vectors and . The general form shown here is the one published by Bartlett.
Proof
() To prove that the backward direction is invertible with inverse given as above) is true, we verify the properties of the inverse. A matrix (in this case the right-hand side of the Sherman–Morrison formula) is the inverse of a matrix (in this case ) if and only if .
We first verify that the right hand side () satisfies .
To end the proof of this direction, we need to show that in a similar way as above:
(In fact, the last step can be avoided since for square matrices and , is equivalent to .)
() Reciprocally, if , then via the matrix determinant lemma, , so is not invertible.
Application
If the inverse of is already known, the formula provides a numerically cheap way to compute the inverse of corrected by the matrix (depending on the point of view, the correction may be seen as a perturbation or as a rank-1 update). The computation is relatively cheap because the inverse of does not have to be computed from scratch (which in general is expensive), but can be computed by correcting (or perturbing) .
Using unit columns (columns from the identity matrix) for or , individual columns or rows of may be manipulated and a correspondingly updated inverse computed relatively cheaply in this way. In the general case, where is a -by- matrix and and are arbitrary vectors of dimension , the whole matrix is updated and the computation takes |
https://en.wikipedia.org/wiki/Lagrange%27s%20identity | In algebra, Lagrange's identity, named after Joseph Louis Lagrange, is:
which applies to any two sets {a1, a2, ..., an} and {b1, b2, ..., bn} of real or complex numbers (or more generally, elements of a commutative ring). This identity is a generalisation of the Brahmagupta–Fibonacci identity and a special form of the Binet–Cauchy identity.
In a more compact vector notation, Lagrange's identity is expressed as:
where a and b are n-dimensional vectors with components that are real numbers. The extension to complex numbers requires the interpretation of the dot product as an inner product or Hermitian dot product. Explicitly, for complex numbers, Lagrange's identity can be written in the form:
involving the absolute value.
Since the right-hand side of the identity is clearly non-negative, it implies Cauchy's inequality in the finite-dimensional real coordinate space Rn and its complex counterpart Cn.
Geometrically, the identity asserts that the square of the volume of the parallelepiped spanned by a set of vectors is the Gram determinant of the vectors.
Lagrange's identity and exterior algebra
In terms of the wedge product, Lagrange's identity can be written
Hence, it can be seen as a formula which gives the length of the wedge product of two vectors, which is the area of the parallelogram they define, in terms of the dot products of the two vectors, as
Lagrange's identity and vector calculus
In three dimensions, Lagrange's identity asserts that if a and b are vectors in R3 with lengths |a| and |b|, then Lagrange's identity can be written in terms of the cross product and dot product:
Using the definition of angle based upon the dot product (see also Cauchy–Schwarz inequality), the left-hand side is
where is the angle formed by the vectors a and b. The area of a parallelogram with sides and and angle is known in elementary geometry to be
so the left-hand side of Lagrange's identity is the squared area of the parallelogram. The cross product appeari |
https://en.wikipedia.org/wiki/Curved%20space | Curved space often refers to a spatial geometry which is not "flat", where a flat space has zero curvature, as described by Euclidean geometry. Curved spaces can generally be described by Riemannian geometry though some simple cases can be described in other ways. Curved spaces play an essential role in general relativity, where gravity is often visualized as curved space. The Friedmann–Lemaître–Robertson–Walker metric is a curved metric which forms the current foundation for the description of the expansion of space and shape of the universe.
Simple two-dimensional example
A very familiar example of a curved space is the surface of a sphere. While to our familiar outlook the sphere looks three-dimensional, if an object is constrained to lie on the surface, it only has two dimensions that it can move in. The surface of a sphere can be completely described by two dimensions since no matter how rough the surface may appear to be, it is still only a surface, which is the two-dimensional outside border of a volume. Even the surface of the Earth, which is fractal in complexity, is still only a two-dimensional boundary along the outside of a volume.
Embedding
One of the defining characteristics of a curved space is its departure from the Pythagorean theorem. In a curved space
.
The Pythagorean relationship can often be restored by describing the space with an extra dimension.
Suppose we have a non-euclidean three-dimensional space with coordinates . Because it is not flat
.
But if we now describe the three-dimensional space with four dimensions () we can choose coordinates such that
.
Note that the coordinate is not the same as the coordinate .
For the choice of the 4D coordinates to be valid descriptors of the original 3D space it must have the same number of degrees of freedom. Since four coordinates have four degrees of freedom it must have a constraint placed on it. We can choose a constraint such that Pythagorean theorem holds in the new 4D space. That is |
https://en.wikipedia.org/wiki/Non-competitive%20inhibition | Non-competitive inhibition is a type of enzyme inhibition where the inhibitor reduces the activity of the enzyme and binds equally well to the enzyme whether or not it has already bound the substrate. This is unlike competitive inhibition, where binding affinity for the substrate in the enzyme is decreased in the presence of an inhibitor.
The inhibitor may bind to the enzyme whether or not the substrate has already been bound, but if it has a higher affinity for binding the enzyme in one state or the other, it is called a mixed inhibitor.
History
During his years working as a physician Michaelis a friend (Peter Rona) built a compact lab, in the hospital, and over the course of five years – Michaelis successfully became published over 100 times. During his research in the hospital, he was the first to view the different types of inhibition; specifically using fructose and glucose as inhibitors of maltase activity. Maltase breaks maltose into two units of glucose. Findings from that experiment allowed for the divergence of non-competitive and competitive inhibition. Non-competitive inhibition affects the kcat value (but not the Km) on any given graph; this inhibitor binds to a site that has specificity for the certain molecule. Michaelis determined that when the inhibitor is bound, the enzyme would become inactivated.
Like many other scientists of their time, Leonor Michaelis and Maud Menten worked on a reaction that was used to change the composition of sucrose and make it lyse into two products – fructose and glucose. The enzyme involved in this reaction is called invertase, and it is the enzyme the kinetics of which have been supported by Michaelis and Menten to be revolutionary for the kinetics of other enzymes. While expressing the rate of the reaction studied, they derived an equation that described the rate in a way which suggested that it is mostly dependent on the enzyme concentration, as well as on presence of the substrate, but only to a certain extent |
https://en.wikipedia.org/wiki/Baguenaudier | Baguenaudier (; French for "time-waster"), also known as the Chinese rings, Cardan's suspension, Cardano's rings, Devil's needle or five pillars puzzle, is a disentanglement puzzle featuring a loop which must be disentangled from a sequence of rings on interlinked pillars. The loop can be either string or a rigid structure.
It is thought to have been invented originally in China. The origins are obscure. The American ethnographer Stewart Culin related a tradition attributing the puzzle's invention to the 2nd/3rd century Chinese general Zhuge Liang. It was used by French peasants as a locking mechanism.
Variations of this include the Devil's staircase, Devil's Halo and the impossible staircase. Another similar puzzle is the Giant's causeway which uses a separate pillar with an embedded ring.
Mathematical solution
The 19th-century French mathematician Édouard Lucas, the inventor of the Tower of Hanoi puzzle, was known to have come up with an elegant solution which used binary and Gray codes, in the same way that his puzzle can be solved. The minimum number of moves to solve an n-ringed problem has been found to be
For other formulae, see .
See also
ABACABA pattern
Disentanglement puzzle
Towers of Hanoi |
https://en.wikipedia.org/wiki/Leibniz%20integral%20rule | In calculus, the Leibniz integral rule for differentiation under the integral sign states that for an integral of the form
where and the integrands are functions dependent on the derivative of this integral is expressible as
where the partial derivative indicates that inside the integral, only the variation of with is considered in taking the derivative. It is named after Gottfried Leibniz.
In the special case where the functions and are constants and with values that do not depend on this simplifies to:
If is constant and , which is another common situation (for example, in the proof of Cauchy's repeated integration formula), the Leibniz integral rule becomes:
This important result may, under certain conditions, be used to interchange the integral and partial differential operators, and is particularly useful in the differentiation of integral transforms. An example of such is the moment generating function in probability theory, a variation of the Laplace transform, which can be differentiated to generate the moments of a random variable. Whether Leibniz's integral rule applies is essentially a question about the interchange of limits.
General form: differentiation under the integral sign
The right hand side may also be written using Lagrange's notation as:
Stronger versions of the theorem only require that the partial derivative exist almost everywhere, and not that it be continuous. This formula is the general form of the Leibniz integral rule and can be derived using the fundamental theorem of calculus. The (first) fundamental theorem of calculus is just the particular case of the above formula where is constant, and does not depend on
If both upper and lower limits are taken as constants, then the formula takes the shape of an operator equation:
where is the partial derivative with respect to and is the integral operator with respect to over a fixed interval. That is, it is related to the symmetry of second derivatives, but invol |
https://en.wikipedia.org/wiki/Minnesota%20Transracial%20Adoption%20Study | The Minnesota Transracial Adoption Study examined the IQ test scores of 130 black or interracial children adopted by advantaged white families. The aim of the study was to determine the contribution of environmental and genetic factors to the poor performance of black children on IQ tests as compared to white children. The initial study was published in 1976 by Sandra Scarr and Richard A. Weinberg. A follow-up study was published in 1992 by Richard Weinberg, Sandra Scarr and Irwin D. Waldman. Another related study investigating social adjustment in a subsample of the adopted black children was published in 1996. The 1992 follow-up study found that "social environment maintains a dominant role in determining the average IQ level of black and interracial children and that both social and genetic variables contribute to individual variations among them."
Background and study design
On measures of cognitive ability (IQ tests) and school performance, black children in the U.S. have performed worse than white children. At the time of the study, the gap in average performance between the two groups of children was approximately one standard deviation, which is equivalent to about 15 IQ points or 4 grade levels at high school graduation. Thus, the average IQ score of black children in the U.S. was approximately 85, compared to the average score of white children of 100. No detectable bias due to test construction or administration had been found, although this does not rule out other biases. The gap is functionally significant, which makes it an important area of study. The Minnesota Transracial Adoption Study tried to answer whether the gap is primarily caused by genetic factors or whether it is primarily caused by environmental and cultural factors.
The study was funded by the Grant Foundation and the National Institute of Child Health and Human Development.
By examining the cognitive ability and school performance of both black and white children adopted into white |
https://en.wikipedia.org/wiki/Animal%20studies | Animal studies is a recently recognised field in which animals are studied in a variety of cross-disciplinary ways. Scholars who engage in animal studies may be formally trained in a number of diverse fields, including art history, anthropology, biology, film studies, geography, history, psychology, literary studies, museology, philosophy, communication, and sociology. They engage with questions about notions of "animality," "animalization," or "becoming animal," to understand human-made representations of and cultural ideas about "the animal" and what it is to be human by employing various theoretical perspectives. Using these perspectives, those who engage in animal studies seek to understand both human-animal relations now and in the past as defined by our knowledge of them. Because the field is still developing, scholars and others have some freedom to define their own criteria about what issues may structure the field.
History
Animal studies became popular in the 1970s as an interdisciplinary subject, animal studies exists at the intersection of a number of different fields of study such as journals and books series, etc. Different fields began to turn to animals as an important topic at different times and for various reasons, and these separate disciplinary histories shape how scholars approach animal studies. Historically, the field of environmental history has encouraged attention to animals.
Throughout Western history, humankind has put itself above the "nonhuman species." In part, animal studies developed out of the animal liberation movement and was grounded in ethical questions about co-existence with other species: whether it is moral to eat animals, to do scientific research on animals for human benefit, and so on. Take rats, for example, with a history of being used as “an experimental subject, feeder, and “pest.” Animal studies scholars who explore the field from an ethical perspective frequently cite Australian philosopher Peter Singer's 1975 wor |
https://en.wikipedia.org/wiki/Phyletic%20gradualism | Phyletic gradualism is a model of evolution which theorizes that most speciation is slow, uniform and gradual. When evolution occurs in this mode, it is usually by the steady transformation of a whole species into a new one (through a process called anagenesis). In this view no clear line of demarcation exists between an ancestral species and a descendant species, unless splitting occurs. The theory is contrasted with punctuated equilibrium.
History
The word phyletic derives from the Greek φυλετικός phūletikos, which conveys the meaning of a line of descent. Phyletic gradualism contrasts with the theory of punctuated equilibrium, which proposes that most evolution occurs isolated in rare episodes of rapid evolution, when a single species splits into two distinct species, followed by a long period of stasis or non-change. These models both contrast with variable-speed evolution ("variable speedism"), which maintains that different species evolve at different rates, and that there is no reason to stress one rate of change over another.
Evolutionary biologist Richard Dawkins argues that constant-rate gradualism is not present in the professional literature, thereby the term serves only as a straw-man for punctuated-equilibrium advocates. In his book The Blind Watchmaker, Dawkins observes that Charles Darwin himself was not a constant-rate gradualist, as suggested by Niles Eldredge and Stephen Jay Gould. In the first edition of On the Origin of Species, Darwin stated that "Species of different genera and classes have not changed at the same rate, or in the same degree. In the oldest tertiary beds a few living shells may still be found in the midst of a multitude of extinct forms... The Silurian Lingula differs but little from the living species of this genus".
Lingula is among the few brachiopods surviving today but also known from fossils over 500 million years old. In the fifth edition of The Origin of Species, Darwin wrote that "the periods during which species |
https://en.wikipedia.org/wiki/Secure%20Real-time%20Transport%20Protocol | The Secure Real-time Transport Protocol (SRTP) is a profile for Real-time Transport Protocol (RTP) intended to provide encryption, message authentication and integrity, and replay attack protection to the RTP data in both unicast and multicast applications. It was developed by a small team of Internet Protocol and cryptographic experts from Cisco and Ericsson. It was first published by the IETF in March 2004 as .
Since RTP is accompanied by the RTP Control Protocol (RTCP) which is used to control an RTP session, SRTP has a sister protocol, called Secure RTCP (SRTCP); it securely provides the same functions to SRTP as the ones provided by RTCP to RTP.
Utilization of SRTP or SRTCP is optional in RTP or RTCP applications; but even if SRTP or SRTCP are used, all provided features (such as encryption and authentication) are optional and can be separately enabled or disabled. The only exception is the message authentication feature which is indispensable and required when using SRTCP.
Data flow encryption
SRTP and SRTCP use Advanced Encryption Standard (AES) as the default cipher. There are two cipher modes defined which allow the AES block cipher to be used as a stream cipher:
Segmented Integer Counter Mode A typical counter mode, which allows random access to any blocks, which is essential for RTP traffic running over unreliable network with possible loss of packets. In the general case, almost any function can be used in the role of counter, assuming that this function does not repeat for a large number of iterations. But the standard for encryption of RTP data is just a usual integer incremental counter. AES running in this mode is the default encryption algorithm, with a default key size of 128 bits and a default session salt key length of 112 bits.
f8-mode A variation of output feedback mode, enhanced to be seekable and with an altered initialization function. The default values of the encryption key and salt key are the same as for AES in counter mode. (AE |
https://en.wikipedia.org/wiki/Grundz%C3%BCge%20der%20Mengenlehre | (German for "Basics of Set Theory") is a book on set theory written by Felix Hausdorff.
First published in April 1914, was the first comprehensive introduction to set theory. Besides the systematic treatment of known results in set theory, the book also contains chapters on measure theory and topology, which were then still considered parts of set theory. Hausdorff presented and developed original material which was later to become the basis for those areas. In 1927 Hausdorff published an extensively revised second edition under the title Mengenlehre (German for "Set Theory"), with many of the topics of the first edition omitted. In 1935 there was a third German edition, which in 1957 was translated by John R. Aumann et al. into English under the title Set Theory.
Chelsea Publishing Company reprinted the German 1914 edition in New York City in German in 1944, 1949, 1965, 1978 and 1991 but never issued an English translation of this first edition (or the 1927 second edition) to date. When the American Mathematical Society took over and set up AMS Chelsea Publishing it published editions in 2005 and 2021. |
https://en.wikipedia.org/wiki/Exploration%20geophysics | Exploration geophysics is an applied branch of geophysics and economic geology, which uses physical methods at the surface of the Earth, such as seismic, gravitational, magnetic, electrical and electromagnetic, to measure the physical properties of the subsurface, along with the anomalies in those properties. It is most often used to detect or infer the presence and position of economically useful geological deposits, such as ore minerals; fossil fuels and other hydrocarbons; geothermal reservoirs; and groundwater reservoirs. It can also be used to detect the presence of unexploded ordnance.
Exploration geophysics can be used to directly detect the target style of mineralization by measuring its physical properties directly. For example, one may measure the density contrasts between the dense iron ore and the lighter silicate host rock, or one may measure the electrical conductivity contrast between conductive sulfide minerals and the resistive silicate host rock.
Geophysical methods
The main techniques used are:
Seismic tomography to locate earthquakes and assist in Seismology.
Reflection seismology and seismic refraction to map the surface structure of a region.
Geodesy and gravity techniques, including gravity gradiometry.
Magnetic techniques, including aeromagnetic surveys to map magnetic anomalies.
Electrical techniques, including electrical resistivity tomography and induced polarization.
Electromagnetic methods, such as magnetotellurics, ground penetrating radar, transient/time-domain electromagnetics, and SNMR.
Borehole geophysics, also called well logging.
Remote sensing techniques, including hyperspectral imaging.
Many other techniques, or methods of integration of the above techniques, have been developed and are currently used. However these are not as common due to cost-effectiveness, wide applicability, and/or uncertainty in the results produced.
Uses
Exploration geophysics is also used to map the subsurface structure of a region, to e |
https://en.wikipedia.org/wiki/Intertec%20Superbrain | The Intertec SuperBrain was an all-in-one commercial microcomputer that was first sold by Intertec Data Systems Corporation of Columbia, South Carolina, USA in 1979. The machine ran the operating system CP/M and was somewhat unusual in that it used dual Z80 CPUs, the second being used as a disk controller. In 1983, the basic machine sold for about .
There were several variants, including the SuperBrain II (released in 1982), SuperBrain II Jr., "QD" (quad density disk drives) and "SD" (super density) models.
Intertec also released a similar looking dumb terminal, the Intertube, and smart terminal, the Emulator.
The SuperBrain is notable for being at the user end of the first Kermit connection in 1981.
The machine was practical and useful in the office environment, but somewhat limited until the arrival of the first 5 MB hard drive in one of the floppy drive bays. This was soon replaced by the 10 MB hard drive.
Up to 255 CompuStar workstations could be daisy-chained together via DC-37 "Chaining Adaptor" parallel ports to share the "central disk system" (one of the three hard drive peripheral options below). Each computer, or VPU (Video Processing Unit), was assigned a unique number from 1 to 255 by setting an eight-position DIP switch.
Specifications
Peripherals
CompuStar DSS-10 10 MB Hard Drive (CompuStar Disk Storage System)
CDC 96 MB Hard Drive (80 MB fixed disk with 16 MB removable platter)
Priam 14" 144 MB Hard Drive
Applications
Microsoft BASIC
8080 Assembler
Microsoft COBOL 74
APL
In pop culture
The Superbrain can be seen in two episodes of Knight Rider: one in Season 1, Episode 10, "The Final Verdict" (1982), and the second in Season 1, Episode 18, "White Bird" (1983).
In John Carpenter’s The Thing, Dr. Blair uses a Superbrain to analyse samples from The Thing from which he estimates that it will take over the world in about three years. |
https://en.wikipedia.org/wiki/Balm%20of%20Gilead | Balm of Gilead was a rare perfume used medicinally, that was mentioned in the Hebrew Bible, and named for the region of Gilead, where it was produced. The expression stems from William Tyndale's language in the King James Bible of 1611, and has come to signify a universal cure in figurative speech. The tree or shrub producing the balm is commonly identified as Commiphora gileadensis. However, some botanical scholars have concluded that the actual source was a terebinth tree in the genus Pistacia.
History
Hebrew Bible
In the Bible, balsam is designated by various names: (bosem), (besem), (ẓori), נָטָף (nataf), which all differ from the terms used in rabbinic literature.
After having cast Joseph into a pit, his brothers noticed a caravan on its way from Gilead to Egypt, "with their camels bearing spicery, and balm, and myrrh" (Gen. ). When Jacob dispatched his embassy into Egypt, his present to the unknown ruler included "a little balm" (Gen. ). During the final years of the Kingdom of Judah, Jeremiah asks "Is there no balm in Gilead?" (Jer. 8:22). Still later, from an expression in Ezekiel , balm was one of the commodities which Hebrew merchants carried to the market of Tyre. According to 1 Kings 10:10, balsam (Hebrew: bosem) was among the many precious gifts of the Queen of Sheba to King Solomon.
Greco-Roman
In the later days of Jewish history, the neighborhood of Jericho was believed to be the only spot where the true balsam grew, and even there its culture was confined to two gardens, the one twenty acres in extent, the other much smaller (Theophrastus).
According to Josephus, the Queen of Sheba brought "the root of the balsam" as a present to King Solomon (Ant. 8.6.6).
In describing Palestine, Tacitus says that in all its productions it equals Italy, besides possessing the palm and the balsam (Hist. 5:6); and the far-famed tree excited the cupidity of successive invaders. By Pompey it was exhibited in the streets of Rome as one of the spoils of the newl |
https://en.wikipedia.org/wiki/Orbicularis%20oculi%20muscle | The orbicularis oculi is a muscle in the face that closes the eyelids. It arises from the nasal part of the frontal bone, from the frontal process of the maxilla in front of the lacrimal groove, and from the anterior surface and borders of a short fibrous band, the medial palpebral ligament.
From this origin, the fibers are directed laterally, forming a broad and thin layer, which occupies the eyelids or palpebræ, surrounds the circumference of the orbit, and spreads over the temple, and downward on the cheek.
Structure
There are at least 3 clearly defined sections of the orbicularis muscle. However, it is not clear whether the lacrimal section is a separate section, or whether it is just an extension of the preseptal and pretarsal sections.
Orbital orbicularis
The orbital portion is thicker and of a reddish color; its fibers form a complete ellipse without interruption at the lateral palpebral commissure; the upper fibers of this portion blend with the frontalis and corrugator.
Palpebral orbicularis
The palpebral portion of the muscle is thin and pale; it arises from the bifurcation of the medial palpebral ligament, forms a series of concentric curves, and is inserted into the lateral palpebral raphe at the outer canthus (corner) of the eye. The palpebral portion contains the preseptal and pretarsal muscles. The pretarsal orbicularis is thought to be responsible for the spontaneous blink.
Lacrimal orbicularis
The lacrimal part is a small, thin muscle, about 6 mm in breadth and 12 mm in length, situated behind the medial palpebral ligament and lacrimal sac. It arises from the posterior crest and adjacent part of the orbital surface of the lacrimal bone, and passing behind the lacrimal sac, divides into two slips, upper and lower, which are inserted into the superior and inferior tarsi medial to the puncta lacrimalia; occasionally it is very indistinct. The lacrimal orbicularis facilitates the tear pump into the lacrimal sac.
Function
The muscle acts to close t |
https://en.wikipedia.org/wiki/Orbital%20part%20of%20frontal%20bone | The orbital or horizontal part of the frontal bone (pars orbitalis) consists of two thin triangular plates, the orbital plates, which form the vaults of the orbits, and are separated from one another by a median gap, the ethmoidal notch.
Surfaces
The inferior surface of each orbital plate is smooth and concave, and presents, laterally, under cover of the zygomatic process, a shallow depression, the lacrimal fossa, for the lacrimal gland; near the nasal part is a depression, the fovea trochlearis, or occasionally a small trochlear spine, for the attachment of the cartilaginous pulley of the obliquus oculi superior.
The superior surface is convex, and marked by depressions for the convolutions of the frontal lobes of the brain, and faint grooves for the meningeal branches of the ethmoidal vessels.
The ethmoidal notch separates the two orbital plates; it is quadrilateral, and filled, in the articulated skull, by the cribriform plate of the ethmoid.
The margins of the notch present several half-cells which, when united with corresponding half-cells on the upper surface of the ethmoid, complete the ethmoidal air cells.
Two grooves cross these edges transversely; they are converted into the anterior and posterior ethmoidal canals by the ethmoid, and open on the medial wall of the orbit.
The anterior canal transmits the nasociliary nerve and anterior ethmoidal vessels,
the posterior, the posterior ethmoidal nerve and vessels.
In front of the ethmoidal notch, on either side of the frontal spine, are the openings of the frontal air sinuses.
These are two irregular cavities, which extend backward, upward, and lateralward for a variable distance between the two tables of the skull; they are separated from one another by a thin bony septum, which often deviates to one or other side, with the result that the sinuses are rarely symmetrical.
Absent at birth, they are usually fairly well-developed between the seventh and eighth years, but only reach their full size afte |
https://en.wikipedia.org/wiki/Frontalis%20muscle | The frontalis muscle () is a muscle which covers parts of the forehead of the skull. Some sources consider the frontalis muscle to be a distinct muscle. However, Terminologia Anatomica currently classifies it as part of the occipitofrontalis muscle along with the occipitalis muscle.
In humans, the frontalis muscle only serves for facial expressions.
The frontalis muscle is supplied by the facial nerve and receives blood from the supraorbital and supratrochlear arteries.
Structure
The frontalis muscle is thin, of a quadrilateral form, and intimately adherent to the superficial fascia. It is broader than the occipitalis and its fibers are longer and paler in color. It is located on the front of the head.
The muscle has no bony attachments. Its medial fibers are continuous with those of the procerus; its intermediate fibers blend with the corrugator and orbicularis oculi muscles, thus attached to the skin of the eyebrows; and its lateral fibers are also blended with the latter muscle over the zygomatic process of the frontal bone.
From these attachments the fibers are directed upward, and join the galea aponeurotica below the coronal suture.
The medial margins of the frontalis muscles are joined together for some distance above the root of the nose; but between the occipitales there is a considerable, though variable, interval, occupied by the galea aponeurotica.
Function
In humans, the frontalis muscle only serves for facial expressions.
In the eyebrows, its primary function is to lift them (thus opposing the orbital portion of the orbicularis), especially when looking up. It also acts when a view is too distant or dim.
The frontalis muscle also serves to wrinkle the forehead.
Additional images
See also
Occipitofrontalis muscle |
https://en.wikipedia.org/wiki/Platform%20screen%20doors | Platform screen doors (PSDs), also known as platform edge doors (PEDs), are used at some train, rapid transit and people mover stations to separate the platform from train tracks, as well as on some bus rapid transit, tram and light rail systems. Primarily used for passenger safety, they are a relatively new addition to many metro systems around the world, some having been retrofitted to established systems. They are widely used in newer Asian and European metro systems, and Latin American bus rapid transit systems.
History
The idea for platform edge doors dates from as early as 1908, when Charles S. Shute of Boston was granted a patent for "Safety fence and gate for railway-platforms". The invention consisted of "a fence for railway platform edges", composed of a series of pickets bolted to the platform edge, and vertically movable pickets that could retract into a platform edge when there was a train in the station. In 1917, Carl Albert West was granted a patent for "Gate for subrailways and the like". The invention provided for spaced guides secured to a tunnel's side wall, with "a gate having its ends guided in the guides, the ends and intermediate portions of the gate having rollers engaging the side wall". Pneumatic cylinders with pistons would be used to raise the gates above the platform when a train was in the station. Unlike Shute's invention, the entire platform gate was movable, and was to retract upward.
The first stations in the world with platform screen doors were the ten stations of the Saint Petersburg Metro's Line 2 that opened between 1961 and 1972. The platform "doors" are actually openings in the station wall, which supports the ceiling of the platform. The track tunnels adjoining the ten stations' island platforms were built with tunnel boring machines (TBMs), and the island platforms were actually located in a separate vault between the two track tunnels. Usually, TBMs bore the deep-level tunnels between stations, while the station vaults |
https://en.wikipedia.org/wiki/Levator%20labii%20superioris | The levator labii superioris (pl. levatores labii superioris, also called quadratus labii superioris, pl. quadrati labii superioris) is a muscle of the human body used in facial expression. It is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone.
Structure
Its medial fibers form the angular head (also known as the levator labii superioris alaeque nasi muscle,) which arises by a pointed extremity from the upper part of the frontal process of the maxilla and passing obliquely downward and lateralward divides into two slips.
One of these is inserted into the greater alar cartilage and skin of the nose; the other is prolonged into the lateral part of the upper lip, blending with the infraorbital head and with the orbicularis oris.
The intermediate portion or infraorbital head arises from the lower margin of the orbit immediately above the infraorbital foramen, some of its fibers being attached to the maxilla, others to the zygomatic bone.
Its fibers converge, to be inserted into the muscular substance of the upper lip between the angular head and the levator anguli oris.
The lateral fibers, forming the zygomatic head (also known as the zygomaticus minor muscle) arise from the malar surface of the zygomatic bone immediately behind the zygomaticomaxillary suture and pass downward and medialward to the upper lip.
Function
Its main function is to elevate the upper lip.
See also
Levator labii superioris alaeque nasi
Additional images |
https://en.wikipedia.org/wiki/Levator%20anguli%20oris | The levator anguli oris (caninus) is a facial muscle of the mouth arising from the canine fossa, immediately below the infraorbital foramen. It elevates angle of mouth medially. Its fibers are inserted into the angle of the mouth, intermingling with those of the zygomaticus, triangularis, and orbicularis oris. Specifically, the levator anguli oris is innervated by the buccal branches of the facial nerve.
Additional images |
https://en.wikipedia.org/wiki/Depressor%20anguli%20oris%20muscle | The depressor anguli oris muscle (triangularis muscle) is a facial muscle. It originates from the mandible and inserts into the angle of the mouth. It is associated with frowning, as it depresses the corner of the mouth.
Structure
The depressor Anguli Oris arises from the lateral surface of the mandible. Its fibers then converge. It is inserted by a narrow fasciculus into the angle of the mouth. At its origin, it is continuous with the platysma muscle, and at its insertion with the orbicularis oris muscle and risorius muscle. Some of its fibers are directly continuous with those of the levator anguli oris muscle, and others are occasionally found crossing from the muscle of one side to that of the other; these latter fibers constitute the transverse muscle of the chin.
The depressor anguli oris muscle receives its blood supply from a branch of the facial artery.
Nerve supply
The depressor anguli oris muscle is supplied by the marginal mandibular branch of the facial nerve.
Function
The depressor anguli oris muscle is a muscle of facial expression. It depresses the corner of the mouth, which is associated with frowning.
Clinical significance
Paralysis
Damage to the marginal mandibular branch of the facial nerve may cause paralysis of the depressor anguli oris muscle. This may contribute to an asymmetrical smile. This may be corrected by resecting (cutting and removing) the depressor labii inferioris muscle, which has a more significant impact on smiling.
Hypoplasia/Aplasia
Underdevelopment (Hypoplasia) or complete absence (Aplasia) of the depressor anguli oris can occur. Similarly to paralysis, individuals with these conditions will have an asymmetric smile. These conditions are rare, and develop at or before birth (congenitally).
See also
Facial muscles
Transverse muscle of the chin
Additional images |
https://en.wikipedia.org/wiki/Risorius | The risorius muscle is a highly variable muscle of facial expression. It has numerous and very variable origins, and inserts into the angle of the mouth. It receives motor innervation from branches of facial nerve (CN VII). It may be absent or asymmetrical in some people. It pulls the angle of the mouth sidewise, such as during smiling.
Structure
The risorius muscle is highly variable.
Attachments
Its peripheral attachments may include (some or all of): the parotid fascia, masseteric fascia, the fascia enveloping the pars modiolaris of the platysma muscle, fascia overlying the mastoid part of temporal bone, and/or the zygomatic arch.
Its apical and subapical (i.e. convergent) attachment is at the modiolus.
Innervation
The risorius receives motor innervation from the buccal branch of the facial nerve (CN VII).
Vasculature
The risorius receives arterial supply mostly from the superior labial artery.
Variation
The risorius muscle is highly variable. It ranges in form from one or more slender bundles to a wide (yet thin) fan. It may be absent in a significant minority of people, and may be asymmetrical.
Relations
It is superficial to the masseter muscle, partially overlying it.
Function
The risorius muscle draws the angle of the mouth lateral-ward. It participates in producing facial expressions like a smile, grin, or laugh.
Clinical significance
Because it partially overlies the masseter muscle, it may be unintentionally affected during botox injections, resulting in unnatural facial expressions.
Other animals
It has been suggested that the risorius muscle is only found in Homininae (African great apes and humans).
Additional images |
https://en.wikipedia.org/wiki/Occipitalis%20muscle | The occipitalis muscle (occipital belly) is a muscle which covers parts of the skull. Some sources consider the occipital muscle to be a distinct muscle. However, Terminologia Anatomica currently classifies it as part of the occipitofrontalis muscle along with the frontalis muscle.
The occipitalis muscle is thin and quadrilateral in form. It arises from tendinous fibers from the lateral two-thirds of the superior nuchal line of the occipital bone and from the mastoid process of the temporal and ends in the epicranial aponeurosis.
The occipitalis muscle is innervated by the facial nerve and its function is to move the scalp back. The muscles receives blood from the occipital artery.
Additional image
See also
Occipitofrontalis muscle |
https://en.wikipedia.org/wiki/Depressor%20septi%20nasi%20muscle | The depressor septi nasi muscle (or depressor alae nasi muscle) is a muscle of the face. It connects the incisive fossa of the maxilla and the orbicularis oris muscle to the nasal septum of the nose. It draws the ala of the nose downwards, reducing the size of the nostrils.
Structure
The depressor septi nasi muscle arises from the incisive foramen of the maxilla. It may also partially originate from the orbicularis oris muscle. Its fibers ascend to be inserted into the nasal septum and back part of the alar part of nasalis muscle.
It lies between the mucous membrane and the muscular structure of the lip.
Function
The depressor septi is a direct antagonist of the other muscles of the nose, drawing the ala of the nose downward, constricting the nostrils.
It works like the alar part of the nasalis muscle.
Clinical significance
During rhinoplasty, repositioning of the head of the depressor septi nasi muscle ensures normal nose position after surgery. Various approaches may be used, with similar results.
Additional images |
https://en.wikipedia.org/wiki/International%20Computer%20Science%20Institute | The International Computer Science Institute (ICSI) is an independent, non-profit research organization located in Berkeley, California, United States. Since its founding in 1988, ICSI has maintained an affiliation agreement with the University of California, Berkeley, where several of its members hold faculty appointments.
Research areas
ICSI's research activities include Internet architecture, network security, network routing, speech and speaker recognition, spoken and text-based natural language processing, computer vision, multimedia, privacy and biological system modeling.
Research groups and leaders
The Institute's director is Dr. Lea Shanley.
SIGCOMM Award winner Professor Scott Shenker, one of the most-cited authors in computer science, is the Chief Scientist and head of the New Initiatives group.
SIGCOMM Award winner Professor Vern Paxson, who leads network security efforts and who previously chaired the Internet Research Task Force.
Professor Jerry Feldman is the head of the Artificial Intelligence Group.
Adjunct Professor Gerald Friedland is the head of the Audio and Multimedia Group.
Dr. Stella Yu is head of the Computer Vision Group.
Dr. Serge Egelman is head of the Usable Security and Privacy Group.
Dr. Steven Wegman is head of the Speech Group.
Notable members and alumni
Turing Award and Kyoto Prize winner Professor Richard Karp is an alumnus and former head of the Algorithms Group.
Professor Nelson Morgan is a former director and former head of the speech group.
Professor Trevor Darrell is an alumnus and former head of the Computer Vision Group.
Professor Krste Asanovic, an ACM Distinguished Scientist, is an alumna and former head of the Computer Architecture Group.
IEEE Internet Award winner Sally Floyd; connectionist pioneer Jerry Feldman; frame semantics and construction grammar pioneer Charles J. Fillmore and Collin F. Baker, who lead the FrameNet semantic parsing project; and Paul Kay, who published an influential study on t |
https://en.wikipedia.org/wiki/Yellowstone%20to%20Yukon%20Conservation%20Initiative | Yellowstone to Yukon Conservation Initiative or Y2Y is a transboundary Canada–United States not-for-profit organization that aims to connect and protect the Yellowstone-to-Yukon region. Its mission proposes to maintain and restore habitat integrity and connectivity along the spine of North America's Rocky Mountains stretching from the Greater Yellowstone ecosystem to Canada's Yukon Territory. It is the only organization dedicated to securing the long-term ecological health of the region.
Since 1993, more than 450 partner groups have joined forces to support the shared mission and vision. Y2Y's work is a collaborative effort of conservation groups, government agencies, Indigenous governments, landowners, wildlife scientists, planners, businesses, economists, and other individuals and groups interested in protecting native wildlife, ecological processes, and wilderness in the Rocky Mountains of North America. Existing national, state, and provincial parks and wilderness areas anchor the system, while the creation of new protected and special management areas provide the additional cores and corridors needed to complete it. This network is built upon the principles of conservation biology, various focal species assessments, the knowledge of local and traditional residents, and the requirements for sustainable economies.
Mission
Connecting and protecting habitat from Yellowstone to Yukon so people and nature can thrive.
Primary role
To achieve its vision across , Y2Y protects core wildlife habitats, keeps those habitats connected and inspires others to engage in similar work.
Y2Y highlights and focuses on local issues that have implications for the region as a whole. The organization engages in landscape-scale conservation, an approach that focuses on actions and management across large areas, such as entire watersheds.
The organization's role is to set the context for regional conservation work by providing the vision for a healthy Yellowstone to Yukon landscap |
https://en.wikipedia.org/wiki/Heinz%20Christian%20Pander | Heinz Christian Pander, also Christian Heinrich Pander ( – ), was a Russian Empire ethnic Baltic German biologist and embryologist.
Biography
In 1817 he received his doctorate from the University of Würzburg, and spent several years (1827–1842), performing scientific research from his estate in Carnikava () on the banks of the Gauja River near Riga. In 1820 he took part in a scientific expedition to Bokhara as a naturalist. In 1826 he became a member of the Saint Petersburg Academy of Sciences.
Research
Pander studied the chick embryo and discovered the germ layers (i.e., three distinct regions of the embryo that give rise to the specific organ system). Because of these findings, he is considered by many to be the "founder of embryology". His work in embryology was continued by Karl Ernst von Baer (1792-1876), who expanded Pander's concept of germ layers to include all vertebrates.
Pander performed important studies in the field of paleontology, being known for his extensive research on fossils found in the Devonian and Silurian geological strata of the Baltic regions. His study of trilobites from this age led to the adjective 'Panderian', first used by the Canadian palaeontologist, Elkanah Billings. Pander is credited as the first scientist to describe primitive creatures known as conodonts.
Today the Pander Society is an international association of palaeontologists and stratigraphers with a common interest in the study of conodonts.
He died in Saint Petersburg.
Eponyms
Pander's eponyms are:
Pander's islands or blood islands
Selected writings
Beiträge zur Entwickelungsgeschichte des Hühnchens im Eye, (Contributions to the embryology involving the chick egg), (1817).
Beiträge zur Naturkunde aus den Ostseeprovinzen Rußlands, (Contributions on the natural history of the Baltic regions) Dorpat, (1820).
Vergleichende Osteologie (Comparative osteology) seven volumes, with Eduard Joseph d'Alton, Bonn: Weber, (1821–1828).
Beiträge zur geognosie des russisch |
https://en.wikipedia.org/wiki/Partial%20veil | In mycology, a partial veil (also called an inner veil, to differentiate it from the "outer", or universal veil) is a temporary structure of tissue found on the fruiting bodies of some basidiomycete fungi, typically agarics. Its role is to isolate and protect the developing spore-producing surface, represented by gills or tubes, found on the lower surface of the cap. A partial veil, in contrast to a universal veil, extends from the stem surface to the cap edge. The partial veil later disintegrates, once the fruiting body has matured and the spores are ready for dispersal. It might then give rise to a stem ring, or fragments attached to the stem or cap edge. In some mushrooms, both a partial veil and a universal veil may be present.
Structure
In the immature fruit bodies of some basidiomycete fungi, the partial veil extends from the stem surface to the cap margin and shields the gills during development, and later breaks to expose the mature gills. The presence, absence, or structure of the partial veil is an aid to identification of mushrooms. Some fruit bodies may have both a universal and partial veil, others may have only one or the other, while many lack both types of veils. The partial veil may be membranous or cobwebby, and may have multiple layers. Various adjectives are commonly used to describe the texture of partial veils, such as: membranous, like a membrane; cottony, where the veil tissue is made of separate fibers that may be easily separated like a cotton ball; fibrillose, composed of thin strands and glutinous, with a slimy consistency. Some mushrooms have partial veils which are evanescent, which are so thin and delicate that they disappear after they rupture, or leave merely a faint trace on the stem known as an annular zone or ring zone. Others may leave a persistent annulus (ring). Occasionally, the partial veil adheres to the edge of the cap as shreds of tissue, forming an appendiculate margin.
The cobweb-like, fragile partial veil of some mus |
https://en.wikipedia.org/wiki/TelecityGroup | Telecity Group plc (formerly TelecityRedbus and before that Telecity), was a European carrier-neutral datacentre and colocation centre provider. It specialised in the design, build and management of datacentre space. It was listed on the London Stock Exchange until it was acquired by Equinix in January 2016.
History
Telecity Group plc was the result of the uniting of three separate companies – TeleCity Limited, Redbus Interhouse Limited and Globix Holdings (UK) Limited. TeleCity Limited was founded by Mike Kelly and Anish Kapoor from Manchester University in April 1998 and opened its first data centre in Manchester. At that time 3i Group made an investment of £24 million in the Company.
In July 1998, Redbus Interhouse Limited was incorporated, and commenced operations in its first data centre in London Docklands in July 1999. By March 2000, Redbus Interhouse Limited floated on the main market of the London Stock Exchange and in June 2000, TeleCity Limited’s parent company, TeleCity plc floated on the London Stock Exchange.
In September 2005, TeleCity plc was taken private by 3i and Oak Hill and by October of that year Telecity Group plc was incorporated and became the holding company of Telecity plc and its group companies in November 2005. In January 2006 Telecity Group acquired Redbus Interhouse plc, a rival business, resulting in the two business, TeleCity and Redbus, trading under the name of TelecityRedbus. Later in 2006 Telecity Group plc bought the European assets of the US-based Globix Corporation.
Following a rebranding exercise implemented in August 2007, TeleCity, Redbus and Globix (UK) began to trade under the name TelecityGroup. In October Telecity Group plc listed on the main market of the London Stock Exchange.
In August 2010, TelecityGroup acquired Internet Facilitators Limited (IFL), a provider of-carrier neutral data centres in Manchester. In August 2011 TelecityGroup acquired Data Electronics, which operates two carrier-neutral data centres i |
https://en.wikipedia.org/wiki/Paxo | Paxo is a brand of stuffing in the United Kingdom, currently owned by Premier Foods.
Paxo was devised in 1901 by John Crampton, a butcher from Eccles near Manchester, who wanted to have something extra to sell to his customers shopping for their Sunday lunch menus.
In the beginning sales growth of Paxo was slow because stuffing is mainly served with chickens and poultry was then traditionally regarded as a luxury. As the price of chickens dropped and that of red meats rose in the 1950s and 1960s, Paxo's popularity grew.
At Christmas, the product is advertised with the slogan "Christmas wouldn't be Christmas without the Paxo" (a play on the phrase "Christmas wouldn't be Christmas without the turkey").
Paxo was manufactured from the early 1950s in Sharston, Manchester, until 2009 when the factory was closed and production moved to the re-opened Bachelor's factory in Ashford, Kent. |
https://en.wikipedia.org/wiki/Limen | In physiology, psychology, or psychophysics, a limen or a liminal point is a sensory threshold of a physiological or psychological response. Such points delineate boundaries of perception; that is, a limen defines a sensory threshold beyond which a particular stimulus becomes perceivable, and below which it remains unperceivable.
Liminal, as an adjective, means situated at a sensory threshold, hence barely perceptible. Subliminal means below perception.
The absolute threshold is the lowest amount of sensation detectable by a sense organ.
See also
Just noticeable difference (least perceptible difference)
Threshold of pain, the boundary where perception becomes pain
Weber–Fechner law (Weber's law) |
https://en.wikipedia.org/wiki/George%20Szekeres | George Szekeres AM FAA (; 29 May 1911 – 28 August 2005) was a Hungarian–Australian mathematician.
Early years
Szekeres was born in Budapest, Hungary, as Szekeres György and received his degree in chemistry at the Technical University of Budapest. He worked six years in Budapest as an analytical chemist. He married Esther Klein in 1937. Being Jewish, the family had to escape from the Nazi persecution so Szekeres took a job in Shanghai, China. There they lived through World War II, the Japanese occupation and the beginnings of the Communist revolution.
Career
In 1948, he was offered a position at the University of Adelaide, Australia, that he gladly accepted. After all the troubles he had had, he began flourishing as a mathematician. In 1963, the family moved to Sydney, where Szekeres took a position at the University of New South Wales, and taught there until his retirement in 1975. He also devised problems for secondary school mathematical olympiads run by the university where he taught, and for a yearly undergraduate competition run by the Sydney University Mathematics Society.
Szekeres worked closely with many prominent mathematicians throughout his life, including Paul Erdős, his wife Esther, Pál Turán, Béla Bollobás, Ronald Graham, Alf van der Poorten, Miklós Laczkovich, and John Coates.
Honours
In 1968 he was the winner of the Thomas Ranken Lyle Medal of the Australian Academy of Science.
In May 2001, a festschrift was held in honour of his ninetieth birthday at the University of New South Wales.
In January 2001 he was awarded the Australian Centenary Medal "for service to Australian society and science in pure mathematics".
In 2001, the Australian Mathematical Society created the George Szekeres Medal in his honour.
In June 2002, he was made a Member of the Order of Australia (AM) 'for service to mathematics and science, particularly as a contributor to education and research, to the support and development of the University of New South Wales Mathema |
https://en.wikipedia.org/wiki/Microemulsion | Microemulsions are clear, thermodynamically stable isotropic liquid mixtures of oil, water and surfactant, frequently in combination with a cosurfactant. The aqueous phase may contain salt(s) and/or other ingredients, and the "oil" may actually be a complex mixture of different hydrocarbons. In contrast to ordinary emulsions, microemulsions form upon simple mixing of the components and do not require the high shear conditions generally used in the formation of ordinary emulsions. The three basic types of microemulsions are direct (oil dispersed in water, o/w), reversed (water dispersed in oil, w/o) and bicontinuous.
In ternary systems such as microemulsions, where two immiscible phases (water and ‘oil’) are present with a surfactant, the surfactant molecules may form a monolayer at the interface between the oil and water, with the hydrophobic tails of the surfactant molecules dissolved in the oil phase and the hydrophilic head groups in the aqueous phase.
Uses
Microemulsions have many commercially important uses:
Water-in-oil microemulsions for some dry cleaning processes
Floor polishers and cleaners
Personal care products
Pesticide formulations
Cutting oils
Drugs
Much of the work done on these systems have been motivated by their possible use to mobilize petroleum trapped in porous sandstone for enhanced oil recovery. A fundamental reason for the uses of these systems is that a microemulsion phase sometimes has an ultralow interfacial tension with a separate oil or aqueous phase, which may release or mobilize them from solid phases even in conditions of slow flow or low pressure gradients.
Microemulsions also have industrial applications, one of them being the synthesis of polymers. Microemulsion polymerization is a complex heterogeneous process where transport of monomers, free radicals and other species (such as chain transfer agent, co-surfactant and inhibitors) between the aqueous and organic phases, takes place. Compared with other heterogeneous po |
https://en.wikipedia.org/wiki/Prismane | Prismane or 'Ladenburg benzene' is a polycyclic hydrocarbon with the formula C6H6. It is an isomer of benzene, specifically a valence isomer. Prismane is far less stable than benzene. The carbon (and hydrogen) atoms of the prismane molecule are arranged in the shape of a six-atom triangular prism—this compound is the parent and simplest member of the prismanes class of molecules. Albert Ladenburg proposed this structure for the compound now known as benzene. The compound was not synthesized until 1973.
History
In the mid 19th century, investigators proposed several possible structures for benzene which were consistent with its empirical formula, C6H6, which had been determined by combustion analysis. The first, which was proposed by Kekulé in 1865, later proved to be closest to the true structure of benzene. This structure inspired several others to draw structures that were consistent with benzene's empirical formula; for example, Ladenburg proposed prismane, Dewar proposed Dewar benzene, and Koerner and Claus proposed Claus' benzene. Some of these structures would be synthesized in the following years. Prismane, like the other proposed structures for benzene, is still often cited in the literature, because it is part of the historical struggle toward understanding the mesomeric structures and resonance of benzene. Some computational chemists still research the differences between the possible isomers of C6H6.
Properties
Prismane is a colourless liquid at room temperature. The deviation of the carbon-carbon bond angle from 109° to 60° in a triangle leads to a high ring strain, reminiscent of that of cyclopropane but greater. The compound is explosive, which is unusual for a hydrocarbon. Due to this ring strain, the bonds have a low bond energy and break at a low activation energy, which makes synthesis of the molecule difficult; Woodward and Hoffmann noted that prismane's thermal rearrangement to benzene is symmetry-forbidden, comparing it to "an angry tiger una |
https://en.wikipedia.org/wiki/Exchange%20bias | Exchange bias or exchange anisotropy occurs in bilayers (or multilayers) of magnetic materials where the hard magnetization behavior of an antiferromagnetic thin film causes a shift in the soft magnetization curve of a ferromagnetic film. The exchange bias phenomenon is of tremendous utility in magnetic recording, where it is used to pin the state of the readback heads of hard disk drives at exactly their point of maximum sensitivity; hence the term "bias."
Fundamental science
The essential physics underlying the phenomenon is the exchange interaction between the antiferromagnet and ferromagnet at their interface. Since antiferromagnets have a small or no net magnetization, their spin orientation is only weakly influenced by an externally applied magnetic field. A soft ferromagnetic film which is strongly exchange-coupled to the antiferromagnet will have its interfacial spins pinned. Reversal of the ferromagnet's moment will have an added energetic cost corresponding to the energy necessary to create a Néel domain wall within the antiferromagnetic film. The added energy term implies a shift in the switching field of the ferromagnet. Thus the magnetization curve of an exchange-biased ferromagnetic film looks like that of the normal ferromagnet except that is shifted away from the H=0 axis by an amount Hb.
In most well-studied ferromagnet/antiferromagnet bilayers, the Curie temperature of the ferromagnet is larger than the Néel temperature TN of the antiferromagnet. This inequality means that the direction of the exchange bias can be set by cooling through TN in the presence of an applied magnetic field. The moment of the magnetically ordered ferromagnet will apply an effective field to the antiferromagnet as it orders, breaking the symmetry and influencing the formation of domains.
The exchange bias effect is attributed to a ferromagnetic unidirectional anisotropy formed at the interface between different magnetic phases. Generally, the process of field c |
https://en.wikipedia.org/wiki/Reliability%20%28computer%20networking%29 | In computer networking, a reliable protocol is a communication protocol that notifies the sender whether or not the delivery of data to intended recipients was successful. Reliability is a synonym for assurance, which is the term used by the ITU and ATM Forum.
Reliable protocols typically incur more overhead than unreliable protocols, and as a result, function more slowly and with less scalability. This often is not an issue for unicast protocols, but it may become a problem for reliable multicast protocols.
Transmission Control Protocol (TCP), the main protocol used on the Internet, is a reliable unicast protocol; it provides the abstraction of a reliable byte stream to applications. UDP is an unreliable protocol and is often used in computer games, streaming media or in other situations where speed is an issue and some data loss may be tolerated because of the transitory nature of the data.
Often, a reliable unicast protocol is also connection oriented. For example, TCP is connection oriented, with the virtual-circuit ID consisting of source and destination IP addresses and port numbers. However, some unreliable protocols are connection oriented, such as Asynchronous Transfer Mode and Frame Relay. In addition, some connectionless protocols, such as IEEE 802.11, are reliable.
History
Building on the packet switching concepts proposed by Donald Davies, the first communication protocol on the ARPANET was a reliable packet delivery procedure to connect its hosts via the 1822 interface. A host computer simply arranged the data in the correct packet format, inserted the address of the destination host computer, and sent the message across the interface to its connected Interface Message Processor (IMP). Once the message was delivered to the destination host, an acknowledgment was delivered to the sending host. If the network could not deliver the message, the IMP would send an error message back to the sending host.
Meanwhile, the developers of CYCLADES and of ALO |
https://en.wikipedia.org/wiki/TO-92 | The TO-92 is a widely used style of semiconductor package mainly used for transistors. The case is often made of epoxy or plastic, and offers compact size at a very low cost.
History and origin
The JEDEC TO-92 descriptor is derived from the original full name for the package: Transistor Outline Package, Case Style 92. The package is also known by the designation SOT54.
By 1966 the package was being used by Motorola for their 2N3904 devices among others.
Construction and orientation
The case is molded around the transistor elements in two parts; the face is flat, usually bearing a machine-printed part number (some early examples had the part number printed on the top surface instead). The back is semi-circularly-shaped. A line of moulding flash from the injection-moulding process can be seen around the case.
The leads protrude from the bottom of the case. When looking at the face of the transistor, the leads are commonly configured from left-to-right as the emitter, base, and collector for 2N series (JEDEC) transistors, however, other configurations are possible, such as emitter, collector, and base commonly used for 2S series (Japanese) transistors or collector, base, and emitter for many of the BC series (Pro Electron) types.
If the face has a part name made up of only one letter and a few numbers, it can be either a Japanese or a Pro Electron part number. Thus, "C1234" would likely be a 2SC1234 device, but "C547" is usually short for "BC547".
The leads coming out of the case are spaced 0.05" (1.27 mm) apart. It is often convenient to bend them outward to a 0.10" (2.54 mm) spacing to make more room for wiring. Units with their leads pre-bent may be ordered to fit specific board layouts, depending on the application. Otherwise, the leads may be bent manually; however, care must be taken as they can break easily, as with any other device that is manually configured.
The physical dimensions of the TO-92 housing may vary slightly depending on the manufact |
https://en.wikipedia.org/wiki/Metagenics | The word metagenics uses the prefix meta and the suffix gen. Literally, it means "the creation of something which creates". In the context of biotechnology, metagenics is the practice of engineering organisms to create a specific enzyme, protein, or other biochemicals from simpler starting materials. The genetic engineering of E. coli with the specific task of producing human insulin from starting amino acids is an example. E. coli has also been engineered to digest plant biomass and use it to produce hydrocarbons in order to synthesize biofuels. The applications of metagenics on E. coli also include higher alcohols, fatty-acid based chemicals and terpenes.
Biofuels
The depletion of petroleum sources and increase in greenhouse gas emissions in the twenty and twenty-first centuries has been the driving factor behind the development of biofuels from microorganisms. E. coli is currently regarded as the best option for biofuel production because of the amount of knowledge available about its genome. The process converts biomass into fuels, and has proven successful on an industrial scale, with the United States having produced 6.4 billion gallons of bioethanol in 2007. Bioethenol is currently the front-runner for alternative fuel production and uses S.cerevisiae and Zymomonas mobilis to create ethanol through fermentation. However, maximum productivity is limited due to the fact that these organisms cannot use pentose sugars, leading to consideration of E.coli and Clostridia. E.coli is capable of producing ethanol under anaerobic conditions through metabolizing glucose into two moles of formate, two moles of acetate, and one mole of ethanol. While bioethanol has proved to be a successful alternative fuel source on an industrial scale, it also has its shortcomings, namely, its low energy density, high vapor pressure, and hygroscopicity. Current alternatives to bioethanol include biobutanol, biodiesel, propanol, and synthetic hydrocarbons. The most common form of biodi |
https://en.wikipedia.org/wiki/Kringle%20domain | Kringle domains are autonomous protein domains that fold into large loops stabilized by 3 disulfide linkages. These are important in protein–protein interactions with blood coagulation factors. Their name refers to the Kringle, a Scandinavian pastry which they somewhat resemble.
Kringle domains have been found in plasminogen, hepatocyte growth factors, prothrombin, and apolipoprotein(a).
Kringles are found throughout the blood clotting and fibrinolytic proteins. Kringle domains are believed to play a role in binding mediators (e.g., membranes, other proteins or phospholipids), and in the regulation of proteolytic activity. Kringle domains are characterised by a triple loop, 3-disulfide bridge structure, whose conformation is defined by a number of hydrogen bonds and small pieces of anti-parallel beta-sheet. They are found in a varying number of copies in some plasma proteins including prothrombin and urokinase-type plasminogen
activator, which are serine proteases belonging to MEROPS peptidase family S1A.
Human proteins containing this domain
ATF; F12; F2; HABP2; HGF; HGFAC; KREMEN1; KREMEN2;
LPA; LPAL2; MST1; PIK3IP1; PLAT; PLAU; PLG; PRSS12; ROR1; ROR2; |
https://en.wikipedia.org/wiki/Intrinsically%20photosensitive%20retinal%20ganglion%20cell | Intrinsically photosensitive retinal ganglion cells (ipRGCs), also called photosensitive retinal ganglion cells (pRGC), or melanopsin-containing retinal ganglion cells (mRGCs), are a type of neuron in the retina of the mammalian eye. The presence of (something like) ipRGCs was first suspected in 1927 when rodless, coneless mice still responded to a light stimulus through pupil constriction, This implied that rods and cones are not the only light-sensitive neurons in the retina. Yet research on these cells did not advance until the 1980s. Recent research has shown that these retinal ganglion cells, unlike other retinal ganglion cells, are intrinsically photosensitive due to the presence of melanopsin, a light-sensitive protein. Therefore, they constitute a third class of photoreceptors, in addition to rod and cone cells.
Overview
Compared to the rods and cones, the ipRGCs respond more sluggishly and signal the presence of light over the long term. They represent a very small subset (~1%) of the retinal ganglion cells. Their functional roles are non-image-forming and fundamentally different from those of pattern vision; they provide a stable representation of ambient light intensity. They have at least three primary functions:
They play a major role in synchronizing circadian rhythms to the 24-hour light/dark cycle, providing primarily length-of-day and length-of-night information. They send light information via the retinohypothalamic tract (RHT) directly to the circadian pacemaker of the brain, the suprachiasmatic nucleus of the hypothalamus. The physiological properties of these ganglion cells match known properties of the daily light entrainment (synchronization) mechanism regulating circadian rhythms. In addition, ipRGCs could also influence peripheral tissues such as the hair follicle regeneration through SCN-sympathetic nerve circuit.
Photosensitive ganglion cells innervate other brain targets, such as the center of pupillary control, the olivary pretectal |
https://en.wikipedia.org/wiki/Mirimanoff%27s%20congruence | In number theory, a branch of mathematics, a Mirimanoff's congruence is one of a collection of expressions in modular arithmetic which, if they hold, entail the truth of Fermat's Last Theorem. Since the theorem has now been proven, these are now of mainly historical significance, though the Mirimanoff polynomials are interesting in their own right. The theorem is due to Dmitry Mirimanoff.
Definition
The nth Mirimanoff polynomial for the prime p is
In terms of these polynomials, if t is one of the six values {-X/Y, -Y/X, -X/Z, -Z/X, -Y/Z, -Z/Y} where Xp+Yp+Zp=0 is a solution to Fermat's Last Theorem, then
φp-1(t) ≡ 0 (mod p)
φp-2(t)φ2(t) ≡ 0 (mod p)
φp-3(t)φ3(t) ≡ 0 (mod p)
...
φ(p+1)/2(t)φ(p-1)/2(t) ≡ 0 (mod p)
Other congruences
Mirimanoff also proved the following:
If an odd prime p does not divide one of the numerators of the Bernoulli numbers Bp-3, Bp-5, Bp-7 or Bp-9, then the first case of Fermat's Last Theorem, where p does not divide X, Y or Z in the equation Xp+Yp+Zp=0, holds.
If the first case of Fermat's Last Theorem fails for the prime p, then 3p-1 ≡ 1 (mod p2). A prime number with this property is sometimes called a Mirimanoff prime, in analogy to a Wieferich prime which is a prime such that 2p-1 ≡ 1 (mod p2). The existence of primes satisfying such congruences was recognized long before their implications for the first case of Fermat's Last Theorem became apparent; but while the discovery of the first Wieferich prime came after these theoretical developments and was prompted by them, the first instance of a Mirimanoff prime is so small that it was already known before Mirimanoff formulated the connection to FLT in 1910, which fact may explain the reluctance of some writers to use the name. So early as his 1895 paper (p. 298), Mirimanoff alludes to a rather complicated test for the primes now known by his name, deriving from a formula published by Sylvester in 1861, which is of little computational value but great theoretical interest. This test |
https://en.wikipedia.org/wiki/Foxtail%20%28diaspore%29 | A foxtail is a spikelet or cluster of a grass, that serves to disperse its seeds as a unit. Thus, the foxtail is a type of diaspore or plant dispersal unit. Some grasses that produce a foxtail are themselves called "foxtail", also "spear grass". They can become a health hazard for dogs, cats, and other domestic animals, and a nuisance for people.
Sources
The name "foxtail" is applied to a number of grasses that have bushy spikes of spikelets that resemble the tail of a fox. Not all of these are hazardous; most of the hazardous ones are in the genus Hordeum, and are also called "wild barley".
Grasses known as foxtails include:
Alopecurus (foxtail grasses — the scientific name literally means "fox tail")
Bromus madritensis (foxtail brome)
Hordeum jubatum (foxtail barley)
Setaria (foxtail millets)
Other grasses also produce hazardous spikelets. The spikelets are sometimes called foxtails, even though the grasses are not.
Structure
All foxtails have a hardened tip, sometimes called a "callus", and retrorse barbs, pointing away from the tip of the callus. Wild barleys have clusters of three spikelets, and the callus is the portion of the rachis to which they attach. In other grasses, such as needlegrass and brome grasses, the foxtail consists of a single spikelet, with the callus being the hardened lemma tip. Retrorse barbs can be found on the callus, the lemmas, and the awns.
The spikelets or spikelet clusters of foxtails are adapted for animal dispersal: The foxtails disarticulate easily, the barbs cause the foxtail to cling to fur, and movement of the animal causes the foxtail to burrow into the fur, since the barbs permit it to move only in the direction of the callus. In wild mammals that inhabit the native ranges of foxtail grasses, the fur is ordinarily short enough that the foxtails will eventually become dislodged, dispersing the seed.
Hazard
Foxtails can become a health hazard for pets and other domestic animals, and a nuisance for people.
In dog |
https://en.wikipedia.org/wiki/Seedling | 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 |
https://en.wikipedia.org/wiki/Mylan | Mylan N.V. was a global generic and specialty pharmaceuticals company. In November 2020, Mylan merged with Upjohn, Pfizer's off-patent medicine division, to form Viatris. Previously, the company was domiciled in the Netherlands, with principal executive offices in Hatfield, Hertfordshire, UK and a "Global Center" in Canonsburg, Pennsylvania, US.
In 2007, the company acquired a controlling interest in India-based Matrix Laboratories Limited, a top producer of active pharmaceutical ingredients (APIs) for generic drugs, and the generics business of Germany-based Merck KGaA. Through these acquisitions, the company grew from the third-largest generic and pharmaceuticals company in the United States to the second-largest generic and specialty pharmaceuticals company in the world.
Mylan went public on the OTC market in February 1973. It was listed on the NASDAQ, and its shares were a component of the NASDAQ Biotechnology and the S&P 500 indices.
The company was founded in 1961 and developed and produced medicines for a wide range of medical disciplines, including oncology, anaphylaxis, antiretrovirals, cardiovascular, respiratory, dermatology, immunology, anesthesia and pain management, infectious disease, gastroenterology, diabetology/endocrinology, and women's healthcare.
Corporate headquarters
Founded in 1961, the company was first located in an abandoned skating rink in White Sulphur Springs, West Virginia. The facility was moved to Pennsauken, New Jersey in 1962, to Princeton, West Virginia in 1963, and then Morgantown, West Virginia, in 1965, and in 1976 it relocated its corporate headquarters to the Pittsburgh suburb Canonsburg, Pennsylvania. Finally in 2004 it moved to a new office center in nearby Southpointe, a suburban business park located in the Pittsburgh suburb of Cecil Township.
Stock
On February 23, 1973, Mylan had its initial public offering (IPO), when it became a publicly traded company on the OTC market under the ticker symbol MYLN. In 1976 the |
https://en.wikipedia.org/wiki/Exercise-induced%20nausea | Exercise-induced nausea is a feeling of sickness or vomiting which can occur shortly after exercise has stopped as well as during exercise itself. It may be a symptom of either over-exertion during exercise, or from too abruptly ending an exercise session. People engaged in high-intensity exercise such as aerobics and bicycling have reported experiencing exercise-induced nausea.
Cause
A study of 20 volunteers conducted at Nagoya University in Japan associated a higher degree of exercise-induced nausea after eating.
Lack of hydration during exercise is a well known cause of headache and nausea. Exercising at a heavy rate causes blood flow to be taken away from the stomach, causing nausea.
Another possible cause of exercise induced nausea is overhydration. Drinking too much water before, during, or after extreme exercise (such as a marathon) can cause nausea, diarrhea, confusion, and muscle tremors. Excessive water consumption reduces or dilutes electrolyte levels in the body causing hyponatremia.
See also
Exercise intolerance
Exercise-induced bronchoconstriction
Exercise-induced urticaria
Exercise-associated hyponatremia
Heat intolerance
Ventilatory threshold |
https://en.wikipedia.org/wiki/Lobes%20of%20the%20brain | The lobes of the brain are the major identifiable zones of the human cerebral cortex, and they comprise the surface of each hemisphere of the cerebrum. The two hemispheres are roughly symmetrical in structure, and are connected by the corpus callosum. They traditionally have been divided into four lobes, but are today considered as having six lobes each. The lobes are large areas that are anatomically distinguishable, and are also functionally distinct to some degree. Each lobe of the brain has numerous ridges, or gyri, and furrows, the sulci that constitute further subzones of the cortex. The expression "lobes of the brain" usually refers only to those of the cerebrum, not to the distinct areas of the cerebellum.
Frontal lobe
The frontal lobe is located at the front of each cerebral hemisphere and positioned in front of the parietal lobe and above and in front of the temporal lobe. It is separated from the parietal lobe by a space between tissues called the central sulcus, and from the temporal lobe by a deep fold called the lateral sulcus also called the Sylvian fissure. The precentral gyrus, which forms the posterior border of the frontal lobe, contains the primary motor cortex (area 4 under the Brodmann area architecture) which controls voluntary movements of specific body parts. The precentral region also contains the premotor cortex (Brodmann area 6).
The frontal lobe contains most of the dopamine-delicate neurons in the cerebral cortex. The dopamine system is associated with reward, attention, short-term memory tasks, planning, and motivation. Dopamine tends to limit and select sensory information arriving from the thalamus to the forebrain. A report from the National Institute of Mental Health says a gene variant that reduces dopamine activity in the prefrontal cortex is related to poorer performance and inefficient functioning of that brain region during working memory tasks, and to a slightly increased risk for schizophrenia.
The frontal lobe consists |
https://en.wikipedia.org/wiki/Location%20information%20server | The location information server, or LIS is a network node originally defined in the National Emergency Number Association i2 network architecture that addresses the intermediate solution for providing e911 service for users of VoIP telephony. The LIS is the node that determines the location of the VoIP terminal.
Beyond the NENA architecture and VoIP, the LIS is capable of providing location information to any IP device within its served access network.
The role of the LIS
Distributed systems for locating people and equipment will be at the heart of tomorrow's active offices. Computer and communications systems continue to proliferate in the office and home. Systems are varied and complex, involving wireless networks and mobile computers. However, systems are underused because the choices of control mechanisms and application interfaces are too diverse. It is therefore pertinent to consider which mechanisms might allow the user to manipulate systems in simple and ubiquitous ways, and how computers can be made more aware of the facilities in their surroundings. Knowledge of the location of people and equipment within an organization is such a mechanism. Annotating a resource database with location information allows location-based heuristics for control and interaction to be constructed. This approach is particularly attractive because location techniques can be devised that are physically unobtrusive and do not rely on explicit user action. The article describes the technology of a system for locating people and equipment, and the design of a distributed system service supporting access to that information. The application interfaces made possible by or that benefit from this facility are presented
Location determination
The method used to determine the location of a device in an access network varies between the different types of networks. For a wired network, such as Ethernet or DSL a wiremap method is common. In wiremap location determination, the locat |
https://en.wikipedia.org/wiki/Institute%20of%20High%20Pressure%20Physics%20of%20the%20Polish%20Academy%20of%20Sciences | Institute of High Pressure Physics, also known as Unipress (Polish: Instytut Wysokich Ciśnień Polskiej Akademii Nauk) is a scientific institute founded in 1972 by the Polish Academy of Sciences (PAN).
Main fields of activity
Biological materials
Food preservation
High-pressure instrumentation
Nanocrystalline materials
Optoelectronics
Semiconductors
Superconductors
Notable people
Sylwester Porowski |
https://en.wikipedia.org/wiki/Toothfriendly%20International | Toothfriendly International is a non-profit association which was established in 1989 in Basel, Switzerland. The purpose of the association is to advance oral health, particularly through preventive measures which include regular oral hygiene (toothbrushing with a fluoridated toothpaste), appropriate dietary habits (avoidance of frequent intake of sugary foods) and regular check-ups by a dentist. It is governed by an executive board of dental professionals.
Since 1989, Toothfriendly International grants the rights for the Toothfriendly quality mark. The Toothfriendly label distinguishes products that are demonstrably not harmful for teeth. The association has national groups in Switzerland, Germany, Turkey, Japan, Korea and Thailand.
The members of the organization are dental professionals, dental and public health institutions, confectionery and oral care manufacturers. |
https://en.wikipedia.org/wiki/Happy%20Tooth | The Happy Tooth is a registered trademark of Toothfriendly International. It stands for guaranteed toothfriendly quality.
The Happy Tooth mark distinguishes products that are not harmful for teeth. In order for products to carry the logo they have to be scientifically tested and proven not to be cariogenic or erosive. The test is based on the measurement of the pH of dental plaque and saliva and is carried out by three appointed independent university institutes.
The compliance of a product is tested by means of intra-oral pH telemetry. Applying a standardized method, the plaque pH is measured at least in four volunteers during and for 30 minutes after consumption of the product with an indwelling, interproximally placed, plaque-covered electrode. Products which do not lower plaque pH below 5.7 under the conditions of this test, lack a cariogenic potential. The erosive potential is measured with a plaque free electrode. The acid exposure of the teeth must not exceed 40 mmol H min. Schachtele Ch.F. et al. (1986). Human plaque acidity models – Working Group Consensus Report. J. Dent. Res., 65 (Spec. Iss.): 1530–1531.
Toothfriendly International grants the rights to use the trademark. |
https://en.wikipedia.org/wiki/Bucranium | Bucranium (plural bucrania; Latin, from Greek βουκράνιον, referring to the skull of an ox) was a form of carved decoration commonly used in Classical architecture. The name is generally considered to originate with the practice of displaying garlanded, sacrificial oxen, whose heads were displayed on the walls of temples, a practice dating back to the sophisticated Neolithic site of Çatalhöyük in eastern Anatolia, where cattle skulls were overlaid with white plaster.
Etymology and sphere of application
The word "bucranium" (latin bucranium) comes from Ancient Greek: βουκράνιον – being composed of βοῦς (ox) and κρανίον (skull) – and literally means "ox skull". Analogic, the Greek word αἰγικράνιον (latin aegicranium) means a "goat skull", also used as a decorative element in architecture.
The technical term "bucranium" was originally used in the description of classical architecture. Its application to the field of prehistoric archeology is relatively recent and is mainly due to the work of the British archaeologist James Mellaart dedicated to the Neolithic site of Çatalhöyük. In 1977, Glyn Daniel established this new meaning of the term, introducing it into the Illustrated Encyclopedia of Archeology.
Overview
In ancient Rome, bucrania were frequently used as metopes between the triglyphs on the friezes of temples designed with the Doric order of architecture. They were also used in bas-relief or painted decor to adorn marble altars, often draped or decorated with garlands of fruit or flowers, many of which have survived.
A rich and festive Doric order was employed at the Basilica Aemilia on the Roman Forum; enough of it was standing for Giuliano da Sangallo to make a drawing, c 1520, reconstructing the facade (Codex Vaticano Barberiniano Latino 4424); the alternation of the shallow libation dishes called paterae with bucrania in the metopes reinforced the solemn sacrificial theme.
While the presence of bucrania was typically used with the Doric order, the Romans |
https://en.wikipedia.org/wiki/Inter-working%20function | The inter-working function (IWF) is a method for interfacing a wireless telecommunication network with the public switched telephone network (PSTN). The IWF converts the data transmitted over the air interface into a format suitable for the PSTN.
IWF contains both the hardware and software elements that provide the rate adaptation and protocol conversion between PSTN and the wireless network.
Some systems require more IWF capability than others, depending on the network which is being connected. The IWF also incorporates a "modem bank", which may be used when, for example, the GSM data terminal equipment (DTE) exchanges data with a land DTE connected via analogue modem
The IWF provides the function to enable the GSM system to interface with the various
forms of public and private data networks currently available.
The basic features of the IWF are:
Data rate adaption
Protocol conversion |
https://en.wikipedia.org/wiki/Traversal%20Using%20Relays%20around%20NAT | Traversal Using Relays around NAT (TURN) is a protocol that assists in traversal of network address translators (NAT) or firewalls for multimedia applications. It may be used with the Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). It is most useful for clients on networks masqueraded by symmetric NAT devices. TURN does not aid in running servers on well known ports in the private network through a NAT; it supports the connection of a user behind a NAT to only a single peer, as in telephony, for example.
TURN is specified by . The TURN URI scheme is documented in .
Introduction
Network address translation (NAT), a mechanism that serves as a measure to mitigate the issue of IPv4 address exhaustion during the transition to IPv6, is accompanied by various limitations. The most troublesome among these limitations is the fact that NAT breaks many existing IP applications, and makes it more difficult to deploy new ones. Guidelines have been developed that describe how to build "NAT friendly" protocols, but many protocols simply cannot be constructed according to those guidelines. Examples of such protocols include multimedia applications and file sharing.
Session Traversal Utilities for NAT (STUN) provides one way for an application to traverse a NAT. STUN allows a client to obtain a transport address (an IP address and port) which may be useful for receiving packets from a peer. However, addresses obtained by STUN may not be usable by all peers. Those addresses work depending on the topological conditions of the network. Therefore, STUN by itself cannot provide a complete solution for NAT traversal.
A complete solution requires a means by which a client can obtain a transport address from which it can receive media from any peer which can send packets to the public Internet. This can only be accomplished by relaying data through a server that resides on the public Internet. Traversal Using Relays around NAT (TURN) is a protocol that allows a cl |
https://en.wikipedia.org/wiki/Neural%20engineering | Neural engineering (also known as neuroengineering) is a discipline within biomedical engineering that uses engineering techniques to understand, repair, replace, or enhance neural systems. Neural engineers are uniquely qualified to solve design problems at the interface of living neural tissue and non-living constructs (Hetling, 2008).
Overview
The field of neural engineering draws on the fields of computational neuroscience, experimental neuroscience, neurology, electrical engineering and signal processing of living neural tissue, and encompasses elements from robotics, cybernetics, computer engineering, neural tissue engineering, materials science, and nanotechnology.
Prominent goals in the field include restoration and augmentation of human function via direct interactions between the nervous system and artificial devices.
Much current research is focused on understanding the coding and processing of information in the sensory and motor systems, quantifying how this processing is altered in the pathological state, and how it can be manipulated through interactions with artificial devices including brain–computer interfaces and neuroprosthetics.
Other research concentrates more on investigation by experimentation, including the use of neural implants connected with external technology.
Neurohydrodynamics is a division of neural engineering that focuses on hydrodynamics of the neurological system.
History
As neural engineering is a relatively new field, information and research relating to it is comparatively limited, although this is changing rapidly. The first journals specifically devoted to neural engineering, The Journal of Neural Engineering and The Journal of NeuroEngineering and Rehabilitation both emerged in 2004. International conferences on neural engineering have been held by the IEEE since 2003, from 29 April until 2 May 2009 in Antalya, Turkey 4th Conference on Neural Engineering, the 5th International IEEE EMBS Conference on Neural Engineeri |
https://en.wikipedia.org/wiki/Formal%20specification | In computer science, formal specifications are mathematically based techniques whose purpose are to help with the implementation of systems and software. They are used to describe a system, to analyze its behavior, and to aid in its design by verifying key properties of interest through rigorous and effective reasoning tools. These specifications are formal in the sense that they have a syntax, their semantics fall within one domain, and they are able to be used to infer useful information.
Motivation
In each passing decade, computer systems have become increasingly more powerful and, as a result, they have become more impactful to society. Because of this, better techniques are needed to assist in the design and implementation of reliable software. Established engineering disciplines use mathematical analysis as the foundation of creating and validating product design. Formal specifications are one such way to achieve this in software engineering reliability as once predicted. Other methods such as testing are more commonly used to enhance code quality.
Uses
Given such a specification, it is possible to use formal verification techniques to demonstrate that a system design is correct with respect to its specification. This allows incorrect system designs to be revised before any major investments have been made into an actual implementation. Another approach is to use probably correct refinement steps to transform a specification into a design, which is ultimately transformed into an implementation that is correct by construction.
It is important to note that a formal specification is not an implementation, but rather it may be used to develop an implementation. Formal specifications describe what a system should do, not how the system should do it.
A good specification must have some of the following attributes: adequate, internally consistent, unambiguous, complete, satisfied, minimal
A good specification will have:
Constructability, manageability and evol |
https://en.wikipedia.org/wiki/Narrow%20class%20group | In algebraic number theory, the narrow class group of a number field K is a refinement of the class group of K that takes into account some information about embeddings of K into the field of real numbers.
Formal definition
Suppose that K is a finite extension of Q. Recall that the ordinary class group of K is defined as the quotient
where IK is the group of fractional ideals of K, and PK is the subgroup of principal fractional ideals of K, that is, ideals of the form aOK where a is an element of K.
The narrow class group is defined to be the quotient
where now PK+ is the group of totally positive principal fractional ideals of K; that is, ideals of the form aOK where a is an element of K such that σ(a) is positive for every embedding
Uses
The narrow class group features prominently in the theory of representing integers by quadratic forms. An example is the following result (Fröhlich and Taylor, Chapter V, Theorem 1.25).
Theorem. Suppose that where d is a square-free integer, and that the narrow class group of K is trivial. Suppose that
is a basis for the ring of integers of K. Define a quadratic form
,
where NK/Q is the norm. Then a prime number p is of the form
for some integers x and y if and only if either
or
or
where dK is the discriminant of K, and
denotes the Legendre symbol.
Examples
For example, one can prove that the quadratic fields Q(), Q(), Q() all have trivial narrow class group. Then, by choosing appropriate bases for the integers of each of these fields, the above theorem implies the following:
A prime p is of the form p = x2 + y 2 for integers x and y if and only if
(This is known as Fermat's theorem on sums of two squares.)
A prime p is of the form p = x2 − 2y 2 for integers x and y if and only if
A prime p is of the form p = x2 − xy + y 2 for integers x and y if and only if
(cf. Eisenstein prime)
An example that illustrates the difference between the narrow class group and the usual class grou |
https://en.wikipedia.org/wiki/Aperture%20%28botany%29 | Apertures are areas on the walls of a pollen grain, where the wall is thinner and/or softer. For germination it is necessary that the pollen tube can reach out from the inside of the pollen grain and transport the sperm to the egg deep down in the pistil. The apertures are the places where the pollen tube is able to break through the (elsewhere very tough) pollen wall.
The number and configuration of apertures are often very exactly characteristic of different groups of plants. In Gymnosperms, pollen is usually sulcate, i.e. has a single aperture placed distally compared to the placement of the pollen grains in the meiotic tetrad. The largest clade of angiosperms, the Eudicots, usually have three apertures that run from the proximal side of the pollen grain to the distal side: this apertures are named colpi, and the pollen type of the Eudicots is called tricolpate. |
https://en.wikipedia.org/wiki/Animal%20trypanosomiasis | Animal trypanosomiasis, also known as nagana and nagana pest, or sleeping sickness, is a disease of vertebrates. The disease is caused by trypanosomes of several species in the genus Trypanosoma such as T. brucei. T. vivax causes nagana mainly in West Africa, although it has spread to South America. The trypanosomes infect the blood of the vertebrate host, causing fever, weakness, and lethargy, which lead to weight loss and anemia; in some animals the disease is fatal unless treated. The trypanosomes are transmitted by tsetse flies.
An interesting feature is the remarkable tolerance to nagana pathology shown by some breeds of cattle, notably the N'Dama – a West African Bos taurus breed. This contrasts with the susceptibility shown by East African B. indicus cattle such as the zebu.
Transmission
Most trypanosomes develop in tsetse flies (Glossina spp.), its biological vector, in about one to a few weeks. When an infected tsetse fly bites an animal, the parasites are transmitted through its saliva. It can also be spread by fomites such as surgical instruments, needles, and syringes. The most important vectors are thought to be horseflies (Tabanidae spp.) and stable flies (Stomoxys spp.).
The immune response of animals may be unable to eliminate trypanosomes completely, and the host may become an inapparent carrier. These inapparent infections can be reactivated if the animal is stressed. Transplacental transmission can also occur.
Transmission was successfully halted on Zanzibar by sterile insect technique (SIT) of the vector Glossina austeni.
Signs and symptoms
The incubation period ranges from four days to approximately eight weeks. The infection leads to significant weight loss and anemia. Various symptoms are observed, including fever, oedema, adenitis, dermatitis and nervous disorders. The disease cannot be diagnosed with certainty except physically detecting parasites by blood microscopic examination or various serological reactions.
Vectors
Control meas |
https://en.wikipedia.org/wiki/Polymatroid | In mathematics, a polymatroid is a polytope associated with a submodular function. The notion was introduced by Jack Edmonds in 1970. It is also described as the multiset analogue of the matroid.
Definition
Let be a finite set and a non-decreasing submodular function, that is, for each we have , and for each we have . We define the polymatroid associated to to be the following polytope:
.
When we allow the entries of to be negative we denote this polytope by , and call it the extended polymatroid associated to .
An equivalent definition
Let be a finite set. If then we denote by the sum of the entries of , and write whenever for every (notice that this gives an order to ). A polymatroid on the ground set is a nonempty compact subset in , the set of independent vectors, such that:
We have that if , then for every :
If with , then there is a vector such that .
This definition is equivalent to the one described before, where is the function defined by for every .
Relation to matroids
To every matroid on the ground set we can associate the set , where is the set of independent sets of and we denote by the characteristic vector of : for every
By taking the convex hull of we get a polymatroid. It is associated to the rank function of . The conditions of the second definition reflect the axioms for the independent sets of a matroid.
Relation to generalized permutahedra
Because generalized permutahedra can be constructed from submodular functions, and every generalized permutahedron has an associated submodular function, we have that there should be a correspondence between generalized permutahedra and polymatroids. In fact every polymatroid is a generalized permutahedron that has been translated to have a vertex in the origin. This result suggests that the combinatorial information of polymatroids is shared with generalized permutahedra.
Properties
is nonempty if and only if and that is nonempty if and only if .
Given any extended |
https://en.wikipedia.org/wiki/Geon%20%28physics%29 | In theoretical general relativity, a geon is a nonsingular electromagnetic or gravitational wave which is held together in a confined region by the gravitational attraction of its own field energy. They were first investigated theoretically in 1955 by J. A. Wheeler, who coined the term as a contraction of "gravitational electromagnetic entity".
Overview
Since general relativity is a classical field theory, Wheeler's concept of a geon does not treat them as quantum-mechanical entities, and this generally remains true today. Nonetheless, Wheeler speculated that there might be a relationship between geons and elementary particles. This idea continues to attract some attention among physicists, but in the absence of a viable theory of quantum gravity, the accuracy of this speculative idea cannot be tested.
Wheeler did not present explicit geon solutions to the vacuum Einstein field equation, a gap which was partially filled by Brill and Hartle in 1964 by the Brill–Hartle geon. In 1997, Anderson and Brill gave a rigorous proof that geon solutions of the vacuum Einstein equation exist, though they are not given in a simple closed form.
A major outstanding question regarding geons is whether they are stable, or must decay over time as the energy of the wave gradually "leaks" away. This question has not yet been definitively answered, but the consensus seems to be that they probably cannot be stable. This would lay to rest Wheeler's initial hope that a geon might serve as a classical model for stable elementary particles. However, this would not rule out the possibility that geons are stabilized by quantum effects. In fact, a quantum generalization of the gravitational geon using low-energy quantum gravity shows that geons are stable systems even when quantum effects are turned on. The quantum geon (called "graviball") is described as gravitons bound by their gravitational self-interaction. Since geons (classical or quantum) have a mass but are electromagneticall |
https://en.wikipedia.org/wiki/Cycloconverter | A cycloconverter (CCV) or a cycloinverter converts a constant amplitude, constant frequency AC waveform to another AC waveform of a lower frequency by synthesizing the output waveform from segments of the AC supply without an intermediate DC link ( and ). There are two main types of CCVs, circulating current type or blocking mode type, most commercial high power products being of the blocking mode type.
Characteristics
Whereas phase-controlled semiconductor controlled rectifier devices (SCR) can be used throughout the range of CCVs, low cost, low-power TRIAC-based CCVs are inherently reserved for resistive load applications. The amplitude and frequency of converters' output voltage are both variable. The output to input frequency ratio of a three-phase CCV must be less than about one-third for circulating current mode CCVs or one-half for blocking mode CCVs. Output waveform quality improves as the pulse number of switching-device bridges in phase-shifted configuration increases in CCV's input. In general, CCVs can be with 1-phase/1-phase, 3-phase/1-phase and 3-phase/3-phase input/output configurations, most applications however being 3-phase/3-phase.
Applications
The competitive power rating span of standardized CCVs ranges from few megawatts up to many tens of megawatts. CCVs are used for driving mine hoists, rolling mill main motors, ball mills for ore processing, cement kilns, ship propulsion systems, slip power recovery wound-rotor induction motors (i.e., Scherbius drives) and aircraft 400 Hz power generation. The variable-frequency output of a cycloconverter can be reduced essentially to zero. This means that very large motors can be started on full load at very slow revolutions, and brought gradually up to full speed. This is invaluable with, for example, ball mills, allowing starting with a full load rather than the alternative of having to start the mill with an empty barrel then progressively load it to full capacity. A fully loaded "hard start" for su |
https://en.wikipedia.org/wiki/Adherens%20junction | Adherens junctions (or zonula adherens, intermediate junction, or "belt desmosome") are protein complexes that occur at cell–cell junctions and cell–matrix junctions in epithelial and endothelial tissues, usually more basal than tight junctions. An adherens junction is defined as a cell junction whose cytoplasmic face is linked to the actin cytoskeleton.
They can appear as bands encircling the cell (zonula adherens) or as spots of attachment to the extracellular matrix (focal adhesion).
Adherens junctions uniquely disassemble in uterine epithelial cells to allow the blastocyst to penetrate between epithelial cells.
A similar cell junction in non-epithelial, non-endothelial cells is the fascia adherens. It is structurally the same, but appears in ribbonlike patterns that do not completely encircle the cells. One example is in cardiomyocytes.
Proteins
Adherens junctions are composed of the following proteins:
cadherins. The cadherins are a family of transmembrane proteins that form homodimers in a calcium-dependent manner with other cadherin molecules on adjacent cells.
p120 (sometimes called delta catenin) binds the juxtamembrane region of the cadherin.
γ-catenin or gamma-catenin (plakoglobin) binds the catenin-binding region of the cadherin.
α-catenin or alpha-catenin binds the cadherin indirectly via β-catenin or plakoglobin and links the actin cytoskeleton with cadherin. Significant protein dynamics are thought to be involved.
Models
Adherens junctions were, for many years, thought to share the characteristic of anchor cells through their cytoplasmic actin filaments.
Adherens junctions may serve as a regulatory module to maintain the actin contractile ring with which it is associated in microscopic studies.
See also
Tight junction |
https://en.wikipedia.org/wiki/List%20of%20Australian%20flags | This is a list of flags of different designs that have been used in Australia.
National flags
Other flags recognised under the Flags Act 1953
Sources:
Personal flags
Sovereign
Governor-General
State governors
Prime Minister
Coronation Standards
Civil ensigns
Australian Defence Force
Royal Australian Navy
Royal Australian Air Force
Australian Border Force
The department names of Australia's border protection service have slightly changed over time, they are as follows;
Department of Trade and Customs (1 January 1901 – 1956)
Department of Customs and Excise (1956–1975)
Department of Police and Customs (1975–1975)
Department of Business and Consumer Affairs (1975–1982)
Department of Industry and Commerce (1982–1984)
Department of Industry, Technology and Commerce (1984–1985)
Australian Customs Service (1985–2009)
Australian Customs and Border Protection Service (2009–2015)
Australian Border Force (2015–present)
Federal and state police
Commonwealth Lighthouse Service
Emergency Services and Health Care flags
Sporting flags
Vexillology Association flags
States and territories
States
Historical
Internal territories
External territories
Historical
Proposed states
Cities and areas
Political flags
Religious flags
Ethnic groups flags
Indigenous
Immigrants
Historical flags
House flags of Australian freight companies
Yacht clubs of Australia
Other flags/Micronational flags
See also
List of proposed Australian flags
Flags of the governors of the Australian states
List of Christmas Island Flags
List of Cocos (Keeling) Islands Flags
List of Norfolk Island Flags
Advance Australia Fair
Australian flag debate
Flag of New Zealand
Notes |
https://en.wikipedia.org/wiki/Steinhaus%E2%80%93Johnson%E2%80%93Trotter%20algorithm | The Steinhaus–Johnson–Trotter algorithm or Johnson–Trotter algorithm, also called plain changes, is an algorithm named after Hugo Steinhaus, Selmer M. Johnson and Hale F. Trotter that generates all of the permutations of elements. Each permutation in the sequence that it generates differs from the previous permutation by swapping two adjacent elements of the sequence. Equivalently, this algorithm finds a Hamiltonian cycle in the permutohedron.
This method was known already to 17th-century English change ringers, and calls it "perhaps the most prominent permutation enumeration algorithm". A version of the algorithm can be implemented in such a way that the average time per permutation is constant. As well as being simple and computationally efficient, this algorithm has the advantage that subsequent computations on the permutations that it generates may be sped up because of the similarity between consecutive permutations that it generates.
Algorithm
The sequence of permutations generated by the Steinhaus–Johnson–Trotter algorithm has a natural recursive structure, that can be generated by a recursive algorithm. However the actual Steinhaus–Johnson–Trotter algorithm does not use recursion, instead computing the same sequence of permutations by a simple iterative method. A later improvement allows it to run in constant average time per permutation.
Recursive structure
The sequence of permutations for a given number can be formed from the sequence of permutations for by placing the number into each possible position in each of the shorter permutations. The Steinhaus–Johnson–Trotter algorithm follows this structure: the sequence of permutations it generates consists of blocks of permutations, so that within each block the permutations agree on the ordering of the numbers from 1 to and differ only in the position of . The blocks themselves are ordered recursively, according to the Steinhaus–Johnson–Trotter algorithm for one less element.
Within each block, the |
https://en.wikipedia.org/wiki/Hdparm | hdparm is a command line program for Linux to set and view ATA hard disk drive hardware parameters and test performance. It can set parameters such as drive caches, sleep mode, power management, acoustic management, and DMA settings. GParted and Parted Magic both include hdparm.
Changing hardware parameters from suboptimal conservative defaults to their optimal settings can improve performance greatly. For example, turning on DMA can, in some instances, double or triple data throughput. There is, however, no reliable method for determining the optimal settings for a given controller-drive combination, except careful trial and error.
Depending on the given parameters, hdparm can cause computer crashes or render the data on the disk inaccessible.
Usage examples
hdparm has to be run with special privileges, otherwise it will either not be found or the requested actions will not be executed properly.
Display information of the hard drive:
sudo hdparm -I /dev/sda
Turn on DMA for the first hard drive:
sudo hdparm -d1 /dev/sda
Test device read performance speed (-t for timing buffered disk reads) of the first hard drive:
sudo hdparm -t /dev/sda
Enable energy saving spindown after inactivity (24*5=120 seconds):
sudo hdparm -S 24 /dev/sda
To retain hdparm settings after a software reset, run:
sudo hdparm -K 1 /dev/sda
Enable read-ahead:
sudo hdparm -A 1 /dev/sda
Change its acoustic management, at the cost of read/write performance (Some drives, such as newer WD drives and all SSDs, ignore this setting.):
sudo hdparm -M 128 /dev/sda
If the disk synchronisation intervals are too short, then even small amounts of data will be written to disk which can have severe consequences for its lifespan. The better way would be to collect small data into bigger chunks and wait until the chunk is big enough to be written to disk.
Current web browsers like Chrome write regularly small chunks when browsing in order not to lose any important data when the application c |
https://en.wikipedia.org/wiki/Jump%20search | In computer science, a jump search or block search refers to a search algorithm for ordered lists. It works by first checking all items Lkm, where and m is the block size, until an item is found that is larger than the search key. To find the exact position of the search key in the list a linear search is performed on the sublist L[(k-1)m, km].
The optimal value of m is , where n is the length of the list L. Because both steps of the algorithm look at, at most, items the algorithm runs in O() time. This is better than a linear search, but worse than a binary search. The advantage over the latter is that a jump search only needs to jump backwards once, while a binary can jump backwards up to log n times. This can be important if jumping backwards takes significantly more time than jumping forward.
The algorithm can be modified by performing multiple levels of jump search on the sublists, before finally performing the linear search. For a k-level jump search the optimum block size ml for the l th level (counting from 1) is n(k-l)/k. The modified algorithm will perform k backward jumps and runs in O(kn1/(k+1)) time.
Implementation
algorithm JumpSearch is
input: An ordered list L, its length n and a search key s.
output: The position of s in L, or nothing if s is not in L.
a ← 0
b ← ⌊√n⌋
while Lmin(b,n)-1 < s do
a ← b
b ← b + ⌊√n⌋
if a ≥ n then
return nothing
while La < s do
a ← a + 1
if a = min(b, n)
return nothing
if La = s then
return a
else
return nothing
See also
Skip list
Interpolation search
Linear search - runs in O(n) time, only looks forward
Binary search - runs in O(log n) time, looks both forward and backward |
https://en.wikipedia.org/wiki/Cliff%20Jones%20%28computer%20scientist%29 | Clifford "Cliff" B. Jones (born 1 June 1944) is a British computer scientist, specializing in research into formal methods. He undertook a late DPhil at the Oxford University Computing Laboratory (now the Oxford University Department of Computer Science) under Tony Hoare, awarded in 1981. Jones' thesis proposed an extension to Hoare logic for handling concurrent programs, rely/guarantee.
Prior to his DPhil, Jones worked for IBM, between the Hursley and Vienna Laboratories. In Vienna, Jones worked with Peter Lucas, Dines Bjørner and others on the Vienna Development Method (VDM), originally as a method for specifying the formal semantics of programming languages, and subsequently for specifying and verifying programs.
Cliff Jones was a professor at the Victoria University of Manchester in the 1980s and early 1990s, worked in industry at Harlequin for a period, and is now a Professor of Computing Science at Newcastle University. He has been editor-in-chief of the Formal Aspects of Computing journal.
As well as formal methods, Jones also has interests in interdisciplinary aspects of computer science and the history of computer science.
Books
Jones has authored and edited many books, including:
Understanding Programming Languages, Jones, C.B. Springer, Cham. Print / online (2020).
Reflections on the Work of C.A.R. Hoare, Roscoe, A.W., Jones, C.B. and Wood, K. (eds.). Springer. (2010).
VDM: Une methode rigoureuse pour le development du logiciel, Jones, C.B. Masson, Paris. (1993).
MURAL: A Formal Development Support System, Jones, C.B., Jones, K.D., Lindsay, P.A. and Moore, R. (eds.). Springer-Verlag. (1991).
Systematic Software Development using VDM (2nd Edition), Jones, C.B. Prentice Hall International Series in Computer Science, Prentice Hall. , 1990
Case Studies in Systematic Software Development, Jones, C.B. and Shaw, R.C.F. (eds.). Prentice Hall International Series in Computer Science, Prentice Hall. (1989).
Essays in Computing Science, Hoare, |
https://en.wikipedia.org/wiki/Opaque%20pointer | In computer programming, an opaque pointer is a special case of an opaque data type, a data type declared to be a pointer to a record or data structure of some unspecified type.
Opaque pointers are present in several programming languages including Ada, C, C++, D and Modula-2.
If the language is strongly typed, programs and procedures that have no other information about an opaque pointer type T can still declare variables, arrays, and record fields of type T, assign values of that type, and compare those values for equality. However, they will not be able to de-reference such a pointer, and can only change the object's content by calling some procedure that has the missing information.
Opaque pointers are a way to hide the implementation details of an interface from ordinary clients, so that the implementation may be changed without the need to recompile the modules using it. This benefits the programmer as well since a simple interface can be created, and most details can be hidden in another file. This is important for providing binary code compatibility through different versions of a shared library, for example.
This technique is described in Design Patterns as the Bridge pattern. It is sometimes referred to as "handle classes", the "Pimpl idiom" (for "pointer to implementation idiom"), "Compiler firewall idiom", "d-pointer" or "Cheshire Cat", especially among the C++ community.
Examples
Ada
package Library_Interface is
type Handle is limited private;
-- Operations...
private
type Hidden_Implementation; -- Defined in the package body
type Handle is access Hidden_Implementation;
end Library_Interface;
The type Handle is an opaque pointer to the real implementation, that is not defined in the specification. Note that the type is not only private (to forbid the clients from accessing the type directly, and only through the operations), but also limited (to avoid the copy of the data structure, and thus preventing dangling references).
p |
https://en.wikipedia.org/wiki/Titan%20Rain | Titan Rain was a series of coordinated attacks on computer systems in the United States since 2003; they were known to have been ongoing for at least three years. The attacks originated in Guangdong, China. The activity is believed to be associated with a state-sponsored advanced persistent threat. It was given the designation Titan Rain by the federal government of the United States.
Titan Rain hackers gained access to many United States defense contractor computer networks, which were targeted for their sensitive information, including those at Lockheed Martin, Sandia National Laboratories, Redstone Arsenal, and NASA.
Attackers
The attacks are reported to be the result of actions by People's Liberation Army Unit 61398. These hackers attacked both the US government (Defense Intelligence Agency) and the UK government (Ministry of Defence). In 2006, an "organised Chinese hacking group" shut down a part of the UK House of Commons computer system. The Chinese government has denied responsibility.
Consequences
The U.S. government has blamed the Chinese government for the 2004 attacks. Alan Paller, SANS Institute research director, stated that the attacks came from individuals with "intense discipline" and that "no other organization could do this if they were not a military". Such sophistication has pointed toward the People's Liberation Army as the attackers.
Titan Rain reportedly attacked multiple organizations, such as NASA and the FBI. Although no classified information was reported stolen, the hackers were able to steal unclassified information (e.g., information from a home computer) that could reveal strengths and weaknesses of the United States.
Titan Rain has also caused distrust between other countries (such as the United Kingdom and Russia) and China. The United Kingdom has stated officially that Chinese hackers attacked its governmental offices. Titan Rain has caused the rest of the world to be more cautious of attacks not just from China but from o |
https://en.wikipedia.org/wiki/Universal%20Data%20Element%20Framework | The Universal Data Element Framework (UDEF) was a controlled vocabulary developed by The Open Group. It provided a framework for categorizing, naming, and indexing data. It assigned to every item of data a structured alphanumeric tag plus a controlled vocabulary name that describes the meaning of the data. This allowed relating data elements to similar elements defined by other organizations.
UDEF defined a Dewey-decimal like code for each concept. For example, an "employee number" is often used in human resource management. It has a UDEF tag a.5_12.35.8 and a controlled vocabulary description "Employee.PERSON_Employer.Assigned.IDENTIFIER".
UDEF has been superseded by the Open Data Element Framework (O-DEF).
Examples
In an application used by a hospital, the last name and first name of several people could include the following example concepts:
Patient Person Family Name – find the word “Patient” under the UDEF object “Person” and find the word “Family” under the UDEF property “Name”
Patient Person Given Name – find the word “Patient” under the UDEF object “Person” and find the word “Given” under the UDEF property “Name”
Doctor Person Family Name – find the word “Doctor” under the UDEF object “Person” and find the word “Family” under the UDEF property “Name”
Doctor Person Given Name – find the word “Doctor” under the UDEF object “Person” and find the word “Given” under the UDEF property “Name”
For the examples above, the following UDEF IDs are available:
“Patient Person Family Name” the UDEF ID is “au.5_11.10”
“Patient Person Given Name” the UDEF ID is “au.5_12.10”
“Doctor Person Family Name” the UDEF ID is “aq.5_11.10”
“Doctor Person Given Name” the UDEF ID is “aq.5_12.10”
See also
Data integration
ISO/IEC 11179
National Information Exchange Model
Metadata
Semantic web
Data element
Representation term
Controlled vocabulary |
https://en.wikipedia.org/wiki/Dines%20Bj%C3%B8rner |
Professor Dines Bjørner (born 4 October 1937, in Odense) is a Danish computer scientist.
He specializes in research into domain engineering, requirements engineering and formal methods. He worked with Cliff Jones and others on the Vienna Development Method (VDM) at IBM Laboratory Vienna (and elsewhere). Later he was involved with producing the RAISE (Rigorous Approach to Industrial Software Engineering) formal method with tool support.
Bjørner was a professor at the Technical University of Denmark (DTU) from 1965–1969 and 1976–2007, before he retired in March 2007. He was responsible for establishing the United Nations University International Institute for Software Technology (UNU-IIST), Macau, in 1992 and was its first director. His magnum opus on software engineering (three volumes) appeared in 2005/6.
To support VDM, Bjørner co-founded VDM-Europe, which subsequently became Formal Methods Europe, an organization that supports conferences and related activities. In 2003, he instigated the associated ForTIA Formal Techniques Industry Association.
Bjørner became a knight of the Order of the Dannebrog in 1985. He received a Dr.h.c. from the Masaryk University, Brno, Czech Republic in 2004. In 2021, he obtained a Dr. techn. from the Technical University of Denmark, Kongens Lyngby, Denmark. He is a Fellow of the IEEE (2004) and ACM (2005). He has also been a member of the Academia Europaea since 1989.
In 2007, a Symposium was held in Macau in honour of Dines Bjørner and Zhou Chaochen. In 2021, Bjørner was elected to a Formal Methods Europe (FME) Fellowship.
Bjørner is married to Kari Bjørner, with two children and five grandchildren.
Selected books
Domain Science and Engineering: A Foundation for Software Development, Bjørner, D. Monographs in Theoretical Computer Science, An EATCS Series, Springer Nature. Hardcover ; softcover ; eBook (2021).
Software Engineering 1: Abstraction and Modelling, Bjørner, D. Texts in Theoretical Computer Science, An EATCS Seri |
https://en.wikipedia.org/wiki/F5%2C%20Inc. | F5, Inc. is a publicly-held American technology company specializing in application security, multi-cloud management, online fraud prevention, application delivery networking (ADN), application availability & performance, network security, and access & authorization.
F5 is headquartered in Seattle, Washington in F5 Tower, with an additional 75 offices in 43 countries focusing on account management, global services support, product development, manufacturing, software engineering, and administrative jobs. Notable office locations include Spokane, Washington; New York, New York; Boulder, Colorado; London, England; San Jose, California; and San Francisco, California.
F5's originally offered application delivery controller (ADC) technology, but expanded into application layer, automation, multi-cloud, and security services. As ransomware, data leaks, DDoS, and other attacks on businesses of all sizes are arising, companies such as F5 have continued to reinvent themselves. While the majority of F5's revenue continues to be attributed to its hardware products such as the BIG-IP iSeries systems, the company has begun to offer additional modules on their proprietary operating system, TMOS (Traffic Management Operating System.) These modules are listed below and include, but are not limited to, Local Traffic Manager (LTM), Advanced Web Application Firewall (AWAF), DNS (previously named GTM), and Access Policy Manager (APM). These offer organizations running the BIG-IP the ability to deploy load balancing, Layer 7 application firewalls, single sign-on (for Azure AD, Active Directory, LDAP, and Okta), as well as enterprise-level VPNs. While the BIG-IP was traditionally a hardware product, F5 now offers it as a virtual machine, which they have branded as the BIG-IP Virtual Edition. The BIG-IP Virtual Edition is cloud agnostic and can be deployed on-premises in a public and/or hybrid cloud environment.
F5's customers include Bank of America, Microsoft, Oracle, Alaska Airlin |
https://en.wikipedia.org/wiki/Pharmacode | Pharmacode, also known as Pharmaceutical Binary Code, is a barcode standard, used in the pharmaceutical industry as a packing control system. It is designed to be readable despite printing errors. It can be printed in multiple colors as a check to ensure that the remainder of the packaging (which the pharmaceutical company must print to protect itself from legal liability) is correctly printed. This barcode is also known as Laetuscode.
For best practice (better security), the code should always contain at least three bars and should always be a combination of both thick and thin bars, (all thick bars or all thin bars do not represent a secure code).
Encoding
Pharmacode can represent only a single integer from 3 to 131070. Unlike other commonly used one-dimensional barcode schemes, pharmacode does not store the data in a form corresponding to the human-readable digits; the number is encoded in binary, rather than decimal. Pharmacode is read from right to left, also in left to right (if omnidirectional scanner): with as the bar position starting at 0 on the right, each narrow bar adds to the value and each wide bar adds . The minimum barcode is 2 bars and the maximum 16, so the smallest number that could be encoded is 3 (2 narrow bars) and the biggest is 131070 (16 wide bars).
It represents colors which are on the label. |
https://en.wikipedia.org/wiki/%CE%92-Hydroxy%20%CE%B2-methylbutyric%20acid | β-Hydroxy β-methylbutyric acid (HMB), otherwise known as its conjugate base, , is a naturally produced substance in humans that is used as a dietary supplement and as an ingredient in certain medical foods that are intended to promote wound healing and provide nutritional support for people with muscle wasting due to cancer or HIV/AIDS. In healthy adults, supplementation with HMB has been shown to increase exercise-induced gains in muscle size, muscle strength, and lean body mass, reduce skeletal muscle damage from exercise, improve aerobic exercise performance, and expedite recovery from exercise. Medical reviews and meta-analyses indicate that HMB supplementation also helps to preserve or increase lean body mass and muscle strength in individuals experiencing age-related muscle loss. HMB produces these effects in part by stimulating the production of proteins and inhibiting the breakdown of proteins in muscle tissue. No adverse effects from long-term use as a dietary supplement in adults have been found.
HMB is sold as a dietary supplement at a cost of about per month when taking 3 grams per day. HMB is also contained in several nutritional products, including certain formulations of Ensure and Juven. HMB is also present in insignificant quantities in certain foods, such as alfalfa, asparagus, avocados, cauliflower, grapefruit, and catfish.
The effects of HMB on human skeletal muscle were first discovered by Steven L. Nissen at Iowa State University in the . HMB has not been banned by the National Collegiate Athletic Association, World Anti-Doping Agency, or any other prominent national or international athletic organization. In 2006, only about 2% of college student athletes in the United States used HMB as a dietary supplement. As of 2017, HMB has found widespread use as an ergogenic supplement among young athletes.
Uses
Available forms
HMB is sold as an over-the-counter dietary supplement in the free acid form, β-hydroxy β-methylbutyric acid (HMB-FA), a |
https://en.wikipedia.org/wiki/Application%20security | Application security (short AppSec) includes all tasks that introduce a secure software development life cycle to development teams. Its final goal is to improve security practices and, through that, to find, fix and preferably prevent security issues within applications. It encompasses the whole application life cycle from requirements analysis, design, implementation, verification as well as maintenance.
Approaches
Different approaches will find different subsets of the security vulnerabilities lurking in an application and are most effective at different times in the software lifecycle. They each represent different tradeoffs of time, effort, cost and vulnerabilities found.
Design review. Before code is written the application's architecture and design can be reviewed for security problems. A common technique in this phase is the creation of a threat model.
Whitebox security review, or code review. This is a security engineer deeply understanding the application through manually reviewing the source code and noticing security flaws. Through comprehension of the application, vulnerabilities unique to the application can be found.
Blackbox security audit. This is only through the use of an application testing it for security vulnerabilities, no source code is required.
Automated Tooling. Many security tools can be automated through inclusion into the development or testing environment. Examples of those are automated DAST/SAST tools that are integrated into code editor or CI/CD platforms.
Coordinated vulnerability platforms. These are hacker-powered application security solutions offered by many websites and software developers by which individuals can receive recognition and compensation for reporting bugs.
Web application security
Web application security is a branch of information security that deals specifically with the security of websites, web applications, and web services. At a high level, web application security draws on the principles of appl |
https://en.wikipedia.org/wiki/Computational%20genomics | Computational genomics refers to the use of computational and statistical analysis to decipher biology from genome sequences and related data, including both DNA and RNA sequence as well as other "post-genomic" data (i.e., experimental data obtained with technologies that require the genome sequence, such as genomic DNA microarrays). These, in combination with computational and statistical approaches to understanding the function of the genes and statistical association analysis, this field is also often referred to as Computational and Statistical Genetics/genomics. As such, computational genomics may be regarded as a subset of bioinformatics and computational biology, but with a focus on using whole genomes (rather than individual genes) to understand the principles of how the DNA of a species controls its biology at the molecular level and beyond. With the current abundance of massive biological datasets, computational studies have become one of the most important means to biological discovery.
History
The roots of computational genomics are shared with those of bioinformatics. During the 1960s, Margaret Dayhoff and others at the National Biomedical Research Foundation assembled databases of homologous protein sequences for evolutionary study. Their research developed a phylogenetic tree that determined the evolutionary changes that were required for a particular protein to change into another protein based on the underlying amino acid sequences. This led them to create a scoring matrix that assessed the likelihood of one protein being related to another.
Beginning in the 1980s, databases of genome sequences began to be recorded, but this presented new challenges in the form of searching and comparing the databases of gene information. Unlike text-searching algorithms that are used on websites such as Google or Wikipedia, searching for sections of genetic similarity requires one to find strings that are not simply identical, but similar. This led to the de |
https://en.wikipedia.org/wiki/Z-variant | In Unicode, two glyphs are said to be Z-variants (often spelled zVariants) if they share the same etymology but have slightly different appearances and different Unicode code points. For example, the Unicode characters U+8AAA 說 and U+8AAC 説 are Z-variants. The notion of Z-variance is only applicable to the "CJKV scripts"—Chinese, Japanese, Korean and Vietnamese—and is a subtopic of Han unification.
Differences on the Z-axis
The Unicode philosophy of code point allocation for CJK languages is organized along three "axes." The X-axis represents differences in semantics; for example, the Latin capital A (U+0041 A) and the Greek capital alpha (U+0391 Α) are represented by two distinct code points in Unicode, and might be termed "X-variants" (though this term is not common). The Y-axis represents significant differences in appearance though not in semantics; for example, the traditional Chinese character māo "cat" (U+8C93 貓) and the simplified Chinese character (U+732B 猫) are Y-variants.
The Z-axis represents minor typographical differences. For example, the Chinese characters (U+838A 莊) and (U+8358 荘) are Z-variants, as are (U+8AAA 說) and (U+8AAC 説). The glossary at Unicode.org defines "Z-variant" as "Two CJK unified ideographs with identical semantics and unifiable shapes," where "unifiable" is taken in the sense of Han unification.
Thus, were Han unification perfectly successful, Z-variants would not exist. They exist in Unicode because it was deemed useful to be able to "round-trip" documents between Unicode and other CJK encodings such as Big5 and CCCII. For example, the character 莊 has CCCII encoding 21552D, while its Z-variant 荘 has CCCII encoding 2D552D. Therefore, these two variants were given distinct Unicode code points, so that converting a CCCII document to Unicode and back would be a lossless operation.
Confusion
There is some confusion over the exact definition of "Z-variant." For example, in an Internet Draft (of ) dated 2002, one finds "no" (U+4E0D |
https://en.wikipedia.org/wiki/Joe%20Stoy | Joseph E. Stoy is a British computer scientist. He initially studied physics at Oxford University. Early in his career, in the 1970s, he worked on denotational semantics with Christopher Strachey in the Programming Research Group at the Oxford University Computing Laboratory (now the Oxford University Department of Computer Science). He was a Fellow of Balliol College, Oxford. He has also spent time at MIT in the United States. In 2003, he co-founded Bluespec, Inc.
His book Denotational Semantics: The Scott-Strachey Approach to Programming Language Semantics (MIT Press, 1977) is now a classic text.
Stoy married Gabrielle Stoy, a mathematician and Fellow of Lady Margaret Hall, Oxford. |
https://en.wikipedia.org/wiki/Picard%20horn | A Picard horn, also called the Picard topology or Picard model, is one of the oldest known hyperbolic 3-manifolds, first described by Émile Picard in 1884. The manifold is the quotient of the upper half-plane model of hyperbolic 3-space by the projective special linear group, . It was proposed as a model for the
shape of the universe in 2004. The term "horn" is due to pseudosphere models of hyperbolic space.
Geometry and topology
A modern description, in terms of fundamental domain and identifications, can be found in section 3.2, page 63 of Grunewald and Huntebrinker, along with the first 80 eigenvalues of the Laplacian, tabulated on page 72, where is a fundamental domain of the Picard space.
Cosmology
The term was coined in 2004 by Ralf Aurich, Sven Lustig, Frank Steiner, and Holger Then in their paper Hyperbolic Universes with a Horned Topology and the CMB Anisotropy.
The model was chosen in an attempt to describe the microwave background radiation apparent in the universe, and has finite volume and useful spectral characteristics (the first several eigenvalues of the Laplacian are computed and in good accord with observation). In this model one end of the figure curves finitely into the bell of the horn. The curve along any side of horn is considered to be a negative curve. The other end extends to infinity.
See also
Gabriel's Horn |
https://en.wikipedia.org/wiki/Jacob%27s%20staff | The term Jacob's staff is used to refer to several things, also known as cross-staff, a ballastella, a fore-staff, a ballestilla, or a balestilha. In its most basic form, a Jacob's staff is a stick or pole with length markings; most staffs are much more complicated than that, and usually contain a number of measurement and stabilization features. The two most frequent uses are:
in astronomy and navigation for a simple device to measure angles, later replaced by the more precise sextants;
in surveying (and scientific fields that use surveying techniques, such as geology and ecology) for a vertical rod that penetrates or sits on the ground and supports a compass or other instrument.
The simplest use of a Jacob's staff is to make qualitative judgements of the height and angle of an object relative to the user of the staff.
In astronomy and navigation
In navigation the instrument is also called a cross-staff and was used to determine angles, for instance the angle between the horizon and Polaris or the sun to determine a vessel's latitude, or the angle between the top and bottom of an object to determine the distance to said object if its height is known, or the height of the object if its distance is known, or the horizontal angle between two visible locations to determine one's point on a map.
The Jacob's staff, when used for astronomical observations, was also referred to as a radius astronomicus. With the demise of the cross-staff, in the modern era the name "Jacob's staff" is applied primarily to the device used to provide support for surveyor's instruments.
Etymology
The origin of the name of the instrument is not certain. Some refer to the Biblical patriarch Jacob, specifically in the Book of Genesis (). It may also take its name after its resemblance to Orion, referred to by the name of Jacob on some medieval star charts. Another possible source is the Pilgrim's staff, the symbol of St James (Jacobus in Latin). The name cross staff simply comes from it |
https://en.wikipedia.org/wiki/KSMO-TV | KSMO-TV (channel 62) is a television station in Kansas City, Missouri, United States, affiliated with MyNetworkTV. It is owned by Gray Television alongside CBS affiliate KCTV (channel 5). Both stations share studios on Shawnee Mission Parkway in Fairway, Kansas, while KSMO-TV's transmitter is located in Independence, Missouri.
Channel 62 in Kansas City began broadcasting as KEKR-TV in 1983, changing its call letters to KZKC in 1985. Originally owned by Media Central of Chattanooga, Tennessee, it suffered for most of its first decade on air from a management style more suited to stations in smaller markets, inferior programming, and a poor reputation. In 1988, the station was fined for airing an indecent film in prime time, attracting national attention. Financial issues also strapped KZKC, particularly after Media Central entered bankruptcy reorganization in 1987.
KZKC was sold out of bankruptcy to First American National Bank of Nashville, Tennessee, in early 1990; the bank quickly sold the station to ABRY Communications. ABRY instituted a top-to-bottom overhaul of programming and facilities, changing the call letters to KSMO-TV in April 1991. The relaunched channel 62 cemented itself as the primary sports and children's station in Kansas City; from 1990 to 1995, viewership tripled and advertising revenue quadrupled. ABRY affiliated the station with UPN upon its January 1995 debut. The station also was the broadcast home of Kansas City Royals baseball for four years, further increasing its visibility.
Sinclair Broadcast Group exercised an option to buy KSMO-TV in December 1995. The station dropped UPN in January 1998 after a corporate dispute between Sinclair and the network; two months later, the station became the new Kansas City affiliate of The WB. With the company focusing on duopolies elsewhere and unable to buy a second station in Kansas City, Sinclair sold KSMO-TV to the Meredith Corporation, then-owner of KCTV, in 2005 after Meredith assumed operating c |
https://en.wikipedia.org/wiki/KMCI-TV | KMCI-TV (channel 38) is an independent television station licensed to Lawrence, Kansas, United States, serving the Kansas City metropolitan area. It is owned by the E. W. Scripps Company alongside NBC affiliate KSHB-TV (channel 41). Both stations share studios on Oak Street in Kansas City, Missouri, while KMCI-TV's transmitter is located at the Blue River Greenway in the city's Hillcrest section. Despite Lawrence being KMCI-TV's city of license, the station maintains no physical presence there.
History
The station first signed on the air on February 1, 1988. Founded by Miller Broadcasting, it originally served as an affiliate of the Home Shopping Network (HSN).
In March 1996, KSHB owner Scripps Howard Broadcasting reached a deal to manage KMCI under a local marketing agreement. That August, KMCI then dropped much of its home shopping programming and rebranded as "38 Family Greats", with a family-oriented general entertainment format from 6:00 a.m. to midnight, with HSN programming being relegated to the overnight hours. The new KMCI lineup included an inventory of programs that KSHB owned but had not had time to air after it switched to NBC in 1994.
Exercising an option from the 1996 pact with Miller, Scripps bought KMCI outright for $14.6 million in 2000, forming a legal duopoly with KSHB. In 2002, KMCI dropped the "Family Greats" branding and simply branded by its channel number. In July 2003, coinciding with the move of its transmitter site from Lawrence toward Kansas City, the station officially became known as "38 the Spot".
Programming
Syndicated programs broadcast on KMCI as of September 2020 include Mike & Molly, Last Man Standing, Family Guy, Divorce Court and 2 Broke Girls, among others. KMCI features hosts that promote the station's programming, as well as local events during commercial breaks. Taunia Hottman was the first spokesperson for KMCI as "38 the Spot". Meredith Hoenes (who became a traffic reporter for KSHB-TV around this time) replaced Hott |
https://en.wikipedia.org/wiki/Web%20Standards%20Project | The Web Standards Project (WaSP) was a group of professional web developers dedicated to disseminating and encouraging the use of the web standards recommended by the World Wide Web Consortium, along with other groups and standards bodies.
Founded in 1998, The Web Standards Project campaigned for standards that reduced the cost and complexity of development while increasing the accessibility and long-term viability of any document published on the Web. WaSP worked with browser companies, authoring tool makers, and peers to encourage them to use these standards, since they "are carefully designed to deliver the greatest benefits to the greatest number of web users". The group disbanded in 2013.
Organization
The Web Standards Project began as a grassroots coalition "fighting for standards in our [web] browsers" founded by George Olsen, Glenn Davis, and Jeffrey Zeldman in August 1998. By 2001, the group had achieved its primary goal of persuading Microsoft, Netscape, Opera, and other browser makers to accurately and completely support HTML 4.01/XHTML 1.0, CSS1, and ECMAScript. Had browser makers not been persuaded to do so, the Web would likely have fractured into pockets of incompatible content, with various websites available only to people who possessed the right browser. In addition to streamlining web development and significantly lowering its cost, support for common web standards enabled the development of the semantic web. By marking up content in semantic (X)HTML, front-end developers make a site's content more available to search engines, more accessible to people with disabilities, and more available to the world beyond the desktop (e.g. mobile).
The project relaunched in June 2002 with new members, a redesigned website, new site features, and a redefined mission focused on developer education and standards compliance in authoring tools as well as browsers.
Project leaders were:
George Olsen (1998–1999)
Jeffrey Zeldman (1999–2002)
Steven Champeon (20 |
https://en.wikipedia.org/wiki/Soundstream | Soundstream Inc. was the first United States audiophile digital audio recording company, providing commercial services for recording and computer-based editing.
Company
Soundstream was founded in 1975 in Salt Lake City, Utah by Dr. Thomas G. Stockham, Jr. The company provided worldwide on-location recording services to Telarc, Delos, RCA, Philips, Vanguard, Varèse Sarabande, Angel, Warner Brothers, CBS, Decca, Chalfont, and other labels. They manufactured a total of 18 digital recorders, of which seven were sold and the rest leased out. Although most recordings were of classical music, the range included country, rock, jazz, pop, and avant-garde.
The first US live digital recording was made in 1976 by Soundstream's prototype 37 kHz, 16-bit, two channel recorder. New World Records recorded the Santa Fe Opera's performance of Virgil Thomson's The Mother of Us All, and provided Soundstream with a stereo feed from their multitrack console. Soundstream demonstrated this recording at the Fall 1976 AES Convention; however the resulting record was pressed not from the digital master but from the analog tape that New World recorded themselves concurrently. Critiques of the recording, most notably from Telarc's Jack Renner and Robert Woods, led directly to the improved four-channel, 50 kHz sample rate recorder that was used for all of Soundstream's future commercial releases.
Also in 1976, Soundstream restored acoustic (pre-electronic) recordings of Enrico Caruso, by digitizing the recordings on a computer, and processing them using a technique called "blind deconvolution". These were released by RCA Records as "Caruso – A Legendary Performer". In subsequent years Soundstream restored most of the RCA Caruso catalog, as well as some RCA recordings by Irish tenor John McCormack.
Soundstream's first commercially released recording, Diahann Carroll With the Duke Ellington Orchestra Under The Direction Of Mercer Ellington – A Tribute To Ethel Waters (on the Orinda label) a |
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