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https://en.wikipedia.org/wiki/Retarded%20position
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Einstein's equations admit gravity wave-like solutions. In the case of a moving point-like mass and in the linearized limit of a weak-gravity approximation these solutions of the Einstein equations are known as the Liénard–Wiechert gravitational potentials. Wave-like solutions (variations) in gravitational field at any point of space at some instant of time t are generated by the mass taken in the preceding (or retarded) instant of time s < t on its world-line at a vertex of the null cone connecting the mass and the field point. The position of the mass that generates the field is called the retarded position and the Liénard–Wiechert potentials are called the retarded potentials. Gravitational waves caused by acceleration of a mass appear to come from the position and direction of the mass at the time it was accelerated (the retarded time and position). The retarded time and the retarded position of the mass are a direct consequence of the finite value of the speed of gravity, the speed with which gravitational waves propagate in space.
As in the case of the Liénard–Wiechert potentials for electromagnetic effects and waves, the static potentials from a moving gravitational mass (i.e., its simple gravitational field, also known as gravitostatic field) are "updated," so that they point to the mass's actual position at constant velocity, with no retardation effects. This happens also for static electric and magnetic effects and is required by Lorentz symmetry, since any mass or charge moving with constant velocity at a great distance, could be replaced by a moving observer at the same distance, with the object now at "rest." In this latter case, the static gravitational field seen by the observer would be required to point to the same position, which is the non-retarded position of the object (mass). Only gravitational waves, caused by acceleration of a mass, and which cannot be removed by a change in a distant observer's inertial frame, must be subject to aberration,
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https://en.wikipedia.org/wiki/Unitary%20divisor
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In mathematics, a natural number a is a unitary divisor (or Hall divisor) of a number b if a is a divisor of b and if a and are coprime, having no common factor other than 1. Equivalently, a divisor a of b is a unitary divisor if and only if every prime factor of a has the same multiplicity in a as it has in b.
The concept of a unitary divisor originates from R. Vaidyanathaswamy (1931), who used the term block divisor.
Example
5 is a unitary divisor of 60, because 5 and have only 1 as a common factor.
On the contrary, 6 is a divisor but not a unitary divisor of 60, as 6 and have a common factor other than 1, namely 2.
Sum of unitary divisors
The sum-of-unitary-divisors function is denoted by the lowercase Greek letter sigma thus: σ*(n). The sum of the k-th powers of the unitary divisors is denoted by σ*k(n):
If the proper unitary divisors of a given number add up to that number, then that number is called a unitary perfect number.
Properties
Number 1 is a unitary divisor of every natural number.
The number of unitary divisors of a number n is 2k, where k is the number of distinct prime factors of n.
This is because each integer N > 1 is the product of positive powers prp of distinct prime numbers p. Thus every unitary divisor of N is the product, over a given subset S of the prime divisors {p} of N,
of the prime powers prp for p ∈ S. If there are k prime factors, then there are exactly 2k subsets S, and the statement follows.
The sum of the unitary divisors of n is odd if n is a power of 2 (including 1), and even otherwise.
Both the count and the sum of the unitary divisors of n are multiplicative functions of n that are not completely multiplicative. The Dirichlet generating function is
Every divisor of n is unitary if and only if n is square-free.
Odd unitary divisors
The sum of the k-th powers of the odd unitary divisors is
It is also multiplicative, with Dirichlet generating function
Bi-unitary divisors
A divisor d of n is a bi-unitary div
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https://en.wikipedia.org/wiki/Continuum%20function
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In mathematics, the continuum function is , i.e. raising 2 to the power of κ using cardinal exponentiation. Given a cardinal number, it is the cardinality of the power set of a set of the given cardinality.
See also
Continuum hypothesis
Cardinality of the continuum
Beth number
Easton's theorem
Gimel function
Cardinal numbers
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https://en.wikipedia.org/wiki/Alphabetic%20principle
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According to the alphabetic principle, letters and combinations of letters are the symbols used to represent the speech sounds of a language based on systematic and predictable relationships between written letters, symbols, and spoken words. The alphabetic principle is the foundation of any alphabetic writing system (such as the English variety of the Latin alphabet, one of the more common types of writing systems in use today). In the education field, it is known as the alphabetic code.
Alphabetic writing systems that use an (in principle) almost perfectly phonemic orthography have a single letter (or digraph or, occasionally, trigraph) for each individual phoneme and a one-to-one correspondence between sounds and the letters that represent them, although predictable allophonic alternation is normally not shown. Such systems are used, for example, in the modern languages Serbo-Croatian (arguably, an example of perfect phonemic orthography), Macedonian, Estonian, Finnish, Italian, Romanian, Spanish, Georgian, Hungarian, Turkish, and Esperanto. The best cases have a straightforward spelling system, enabling a writer to predict the spelling of a word given its pronunciation and similarly enabling a reader to predict the pronunciation of a word given its spelling. Ancient languages with such almost perfectly phonemic writing systems include Avestic, Latin, Vedic, and Sanskrit (Devanāgarī—an abugida; see Vyakarana). On the other hand, French and English have a strong difference between sounds and symbols.
The alphabetic principle is closely tied to phonics, as it is the systematic relationship between spoken words and their visual representation (letters).
The alphabetic principle does not underlie logographic writing systems like Chinese or syllabic writing systems such as Japanese kana. Korean was formerly written partially with Chinese characters, but is now written in the fully alphabetic Hangul system, in which the letters are not written linearly, but arranged
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https://en.wikipedia.org/wiki/Threshold%20energy
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In particle physics, the threshold energy for production of a particle is the minimum kinetic energy that must be imparted to one of a pair of particles in order for their collision to produce a given result. If the desired result is to produce a third particle then the threshold energy is greater than or equal to the rest energy of the desired particle. In most cases, since momentum is also conserved, the threshold energy is significantly greater than the rest energy of the desired particle.
The threshold energy should not be confused with the threshold displacement energy, which is the minimum energy needed to permanently displace an atom in a crystal to produce a crystal defect in radiation material science.
Example of pion creation
Consider the collision of a mobile proton with a stationary proton so that a meson is produced:
We can calculate the minimum energy that the moving proton must have in order to create a pion.
Transforming into the ZMF (Zero Momentum Frame or Center of Mass Frame) and assuming the outgoing particles have no KE (kinetic energy) when viewed in the ZMF, the conservation of energy equation is:
Rearranged to
By assuming that the outgoing particles have no KE in the ZMF, we have effectively considered an inelastic collision in which the product particles move with a combined momentum equal to that of the incoming proton in the Lab Frame.
Our terms in our expression will cancel, leaving us with:
Using relativistic velocity additions:
We know that is equal to the speed of one proton as viewed in the ZMF, so we can re-write with :
So the energy of the proton must be MeV.
Therefore, the minimum kinetic energy for the proton must be MeV.
Example of antiproton creation
At higher energy, the same collision can produce an antiproton:
If one of the two initial protons is stationary, we find that the impinging proton must be given at least of energy, that is, 5.63 GeV. On the other hand, if both protons are accelerated one towards
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https://en.wikipedia.org/wiki/Available%20energy%20%28particle%20collision%29
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In particle physics, the available energy is the energy in a particle collision available to produce new particles from the energy of the colliding particles.
In early accelerators both colliding particles usually survived after the collision, so the available energy was the total kinetic energy of the colliding particles in the center-of-momentum frame before the collision. In modern accelerators particles collide with their anti-particles and can annihilate, so the available energy includes both the kinetic energy and the rest energy of the colliding particles in the center-of-momentum frame before the collision.
See also
Threshold energy
Matter creation
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https://en.wikipedia.org/wiki/Sealant
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Sealant is a substance used to block the passage of fluids through openings in materials, a type of mechanical seal. In building construction sealant is sometimes synonymous with caulk (especially if acrylic latex or polyurethane based) and also serve the purposes of blocking dust, sound and heat transmission. Sealants may be weak or strong, flexible or rigid, permanent or temporary. Sealants are not adhesives but some have adhesive qualities and are called adhesive-sealants or structural sealants.
History
Sealants were first used in prehistory in the broadest sense as mud, grass and reeds to seal dwellings from the weather such as the daub in wattle and daub and thatching. Natural sealants and adhesive-sealants included plant resins such as pine pitch and birch pitch, bitumen, wax, tar, natural gum, clay (mud) mortar, lime mortar, lead, blood and egg. In the 17th century glazing putty was first used to seal window glass made with linseed oil and chalk, later other drying oils were also used to make oil-based putties. In the 1920s polymers such as acrylic polymers, butyl polymers and silicone polymers were first developed and used in sealants. By the 1960s synthetic-polymer-based sealants were widely available.
Function
Sealants, despite not having great strength, convey a number of properties. They seal top structures to the substrate, and are particularly effective in waterproofing processes by keeping moisture out (or in) the components in which they are used. They can provide thermal and acoustical insulation, and may serve as fire barriers. They may have electrical properties, as well. Sealants can also be used for simple smoothing or filling. They are often called upon to perform several of these functions at once.
A caulking sealant has three basic functions: It fills a gap between two or more substrates; it forms a barrier through the physical properties of the sealant itself and by adhesion to the substrate; and it maintains sealing properties for the ex
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https://en.wikipedia.org/wiki/Multi-scale%20approaches
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The scale space representation of a signal obtained by Gaussian smoothing satisfies a number of special properties, scale-space axioms, which make it into a special form of multi-scale representation. There are, however, also other types of "multi-scale approaches" in the areas of computer vision, image processing and signal processing, in particular the notion of wavelets. The purpose of this article is to describe a few of these approaches:
Scale-space theory for one-dimensional signals
For one-dimensional signals, there exists quite a well-developed theory for continuous and discrete kernels that guarantee that new local extrema or zero-crossings cannot be created by a convolution operation. For continuous signals, it holds that all scale-space kernels can be decomposed into the following sets of primitive smoothing kernels:
the Gaussian kernel : where ,
truncated exponential kernels (filters with one real pole in the s-plane):
if and 0 otherwise where
if and 0 otherwise where ,
translations,
rescalings.
For discrete signals, we can, up to trivial translations and rescalings, decompose any discrete scale-space kernel into the following primitive operations:
the discrete Gaussian kernel
where where are the modified Bessel functions of integer order,
generalized binomial kernels corresponding to linear smoothing of the form
where
where ,
first-order recursive filters corresponding to linear smoothing of the form
where
where ,
the one-sided Poisson kernel
for where
for where .
From this classification, it is apparent that we require a continuous semi-group structure, there are only three classes of scale-space kernels with a continuous scale parameter; the Gaussian kernel which forms the scale-space of continuous signals, the discrete Gaussian kernel which forms the scale-space of discrete signals and the time-causal Poisson kernel that forms a temporal scale-space over discrete time. If we on the other hand sacrifice the continuous se
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https://en.wikipedia.org/wiki/Complex%20metallic%20alloy
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Complex metallic alloys (CMAs) or complex intermetallics (CIMs) are intermetallic compounds characterized by the following structural features:
large unit cells, comprising some tens up to thousands of atoms,
the presence of well-defined atom clusters, frequently of icosahedral point group symmetry,
the occurrence of inherent disorder in the ideal structure.
Overview
Complex metallic alloys is an umbrella term for intermetallic compounds with a relatively large unit cell. There is no precise definition of how large the unit cell of a complex metallic alloy has to be, but the broadest definition includes Zintl phases, skutterudites, and Heusler compounds on the most simple end, and quasicrystals on the more complex end.
Research
Following the invention of X-ray crystallography techniques in the 1910s, the atomic structure of many compounds was investigated. Most metals have relatively simple structures. However, in 1923 Linus Pauling reported on the structure of the intermetallic NaCd2, which had such a complicated structure he was unable to fully explain it. Thirty years later, he concluded that NaCd2 contains 384 sodium and 768 cadmium atoms in each unit cell.
Most physical properties of CMAs show distinct differences with respect to the behavior of normal metallic alloys and therefore these materials possess a high potential for technological application.
The European Commission funded the Network of Excellence CMA from 2005 to 2010, uniting 19 core groups in 12 countries. From this emerged the European Integrated Center for the Development of New Metallic Alloys and Compounds (previously C-MAC, now ECMetAC), which connects researchers at 21 universities.
Examples
Example phases are:
β-Mg2Al3: 1168 atoms per unit cell, face-centred cubic, atoms arranged in Friauf polyhedra.
ξ'–Al74Pd22Mn4: 318 atoms per unit cell, face-centred orthorhombic, atoms arranged in Mackay-type clusters.
(Bergman phase): 163 atoms per unit cell, body centred cubic, atoms arran
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https://en.wikipedia.org/wiki/Strict%20differentiability
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In mathematics, strict differentiability is a modification of the usual notion of differentiability of functions that is particularly suited to p-adic analysis. In short, the definition is made more restrictive by allowing both points used in the difference quotient to "move".
Basic definition
The simplest setting in which strict differentiability can be considered, is that of a real-valued function defined on an interval I of the real line.
The function f:I → R is said strictly differentiable in a point a ∈ I if
exists, where is to be considered as limit in , and of course requiring .
A strictly differentiable function is obviously differentiable, but the converse is wrong, as can be seen from the counter-example
One has however the equivalence of strict differentiability on an interval I, and being of differentiability class (i.e. continuously differentiable).
In analogy with the Fréchet derivative, the previous definition can be generalized to the case where R is replaced by a Banach space E (such as ), and requiring existence of a continuous linear map L such that
where is defined in a natural way on E × E.
Motivation from p-adic analysis
In the p-adic setting, the usual definition of the derivative fails to have certain desirable properties. For instance, it is possible for a function that is not locally constant to have zero derivative everywhere. An example of this is furnished by the function F: Zp → Zp, where Zp is the ring of p-adic integers, defined by
One checks that the derivative of F, according to usual definition of the derivative, exists and is zero everywhere, including at x = 0. That is, for any x in Zp,
Nevertheless F fails to be locally constant at the origin.
The problem with this function is that the difference quotients
do not approach zero for x and y close to zero. For example, taking x = pn − p2n and y = pn, we have
which does not approach zero. The definition of strict differentiability avoids this problem by impo
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https://en.wikipedia.org/wiki/Walter%20Rudin
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Walter Rudin (May 2, 1921 – May 20, 2010) was an Austrian-American mathematician and professor of Mathematics at the University of Wisconsin–Madison.
In addition to his contributions to complex and harmonic analysis, Rudin was known for his mathematical analysis textbooks: Principles of Mathematical Analysis, Real and Complex Analysis, and Functional Analysis. Rudin wrote Principles of Mathematical Analysis only two years after obtaining his Ph.D. from Duke University, while he was a C. L. E. Moore Instructor at MIT. Principles, acclaimed for its elegance and clarity, has since become a standard textbook for introductory real analysis courses in the United States.
Rudin's analysis textbooks have also been influential in mathematical education worldwide, having been translated into 13 languages, including Russian, Chinese, and Spanish.
Biography
Rudin was born into a Jewish family in Austria in 1921. He was enrolled for a period of time at a Swiss boarding school, the Institut auf dem Rosenberg, where he was part of a small program that prepared its students for entry to British universities. His family fled to France after the Anschluss in 1938.
When France surrendered to Germany in 1940, Rudin fled to England and served in the Royal Navy for the rest of World War II, after which he left for the United States. He obtained both his B.A. in 1947 and Ph.D. in 1949 from Duke University. After his Ph.D., he was a C.L.E. Moore instructor at MIT. He briefly taught at the University of Rochester before becoming a professor at the University of Wisconsin–Madison where he remained for 32 years. His research interests ranged from harmonic analysis to complex analysis.
In 1970 Rudin was an Invited Speaker at the International Congress of Mathematicians in Nice. He was awarded the Leroy P. Steele Prize for Mathematical Exposition in 1993 for authorship of the now classic analysis texts, Principles of Mathematical Analysis and Real and Complex Analysis. He received an ho
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https://en.wikipedia.org/wiki/Computational%20visualistics
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The term Computational visualistics addresses the whole range of scientifically investigating pictures "in" the computer.
Overview
Images take a rather prominent place in contemporary life in western societies. Together with language, they have been connected to human culture from the very beginning. For about one century – after several millennia of written word's dominance – their part is increasing again remarkably. Steps toward a general science of images, which we may call 'general visualistics' in analogy to general linguistics, have only been taken recently. So far, a unique scientific basis for circumscribing and describing the heterogeneous phenomenon "image" in an interpersonally verifiable manner has still been missing while distinct aspects falling in the domain of visualistics have predominantly been dealt with in several other disciplines, among them in particular philosophy, psychology, and art history. Last (though not least), important contributions to certain aspects of the new science of images have come from computer science.
In computer science, too, considering pictures evolved originally along several more or less independent questions, which lead to proper sub-disciplines: computer graphics is certainly the most "visible" among them. Only recently, the effort has been increased to finally form a unique and partially autonomous branch of computer science dedicated to images. In analogy to computational linguistics, the artificial expression computational visualistics is used for addressing the whole range of investigating scientific pictures "in" the computer.
Areas covered
For a science of images within computer science, the abstract data type "image" (or perhaps several such types) stands in the center of interest together with the potential implementations. There are three main groups of algorithms for that data type to be considered in computational visualistics:
Algorithms from "image" to "image"
In the field called image processin
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https://en.wikipedia.org/wiki/Limit%20set
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In mathematics, especially in the study of dynamical systems, a limit set is the state a dynamical system reaches after an infinite amount of time has passed, by either going forward or backwards in time. Limit sets are important because they can be used to understand the long term behavior of a dynamical system. A system that has reached its limiting set is said to be at equilibrium.
Types
fixed points
periodic orbits
limit cycles
attractors
In general, limits sets can be very complicated as in the case of strange attractors, but for 2-dimensional dynamical systems the Poincaré–Bendixson theorem provides a simple characterization of all nonempty, compact -limit sets that contain at most finitely many fixed points as a fixed point, a periodic orbit, or a union of fixed points and homoclinic or heteroclinic orbits connecting those fixed points.
Definition for iterated functions
Let be a metric space, and let be a continuous function. The -limit set of , denoted by , is the set of cluster points of the forward orbit of the iterated function . Hence, if and only if there is a strictly increasing sequence of natural numbers such that as . Another way to express this is
where denotes the closure of set . The points in the limit set are non-wandering (but may not be recurrent points). This may also be formulated as the outer limit (limsup) of a sequence of sets, such that
If is a homeomorphism (that is, a bicontinuous bijection), then the -limit set is defined in a similar fashion, but for the backward orbit; i.e. .
Both sets are -invariant, and if is compact, they are compact and nonempty.
Definition for flows
Given a real dynamical system with flow , a point , we call a point y an -limit point of if there exists a sequence in so that
.
For an orbit of , we say that is an -limit point of , if it is an -limit point of some point on the orbit.
Analogously we call an -limit point of if there exists a sequence in so that
.
For a
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https://en.wikipedia.org/wiki/Bar%20induction
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Bar induction is a reasoning principle used in intuitionistic mathematics, introduced by L. E. J. Brouwer. Bar induction's main use is the intuitionistic derivation of the fan theorem, a key result used in the derivation of the uniform continuity theorem.
It is also useful in giving constructive alternatives to other classical results.
The goal of the principle is to prove properties for all infinite sequences of natural numbers (called choice sequences in intuitionistic terminology), by inductively reducing them to properties of finite lists. Bar induction can also be used to prove properties about all choice sequences in a spread (a special kind of set).
Definition
Given a choice sequence , any finite sequence of elements of this sequence is called an initial segment of this choice sequence.
There are three forms of bar induction currently in the literature, each one places certain restrictions on a pair of predicates and the key differences are highlighted using bold font.
Decidable bar induction (BID)
Given two predicates and on finite sequences of natural numbers such that all of the following conditions hold:
every choice sequence contains at least one initial segment satisfying at some point (this is expressed by saying that is a bar);
is decidable (i.e. our bar is decidable);
every finite sequence satisfying also satisfies (so holds for every choice sequence beginning with the aforementioned finite sequence);
if all extensions of a finite sequence by one element satisfy , then that finite sequence also satisfies (this is sometimes referred to as being upward hereditary);
then we can conclude that holds for the empty sequence (i.e. A holds for all choice sequences starting with the empty sequence).
This principle of bar induction is favoured in the works of, A. S. Troelstra, S. C. Kleene and Albert Dragalin.
Thin bar induction (BIT)
Given two predicates and on finite sequences of natural numbers such that all of the following co
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https://en.wikipedia.org/wiki/ABMAP
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ABMAP, also known as the Animal Bone Metrical Archive Project, consists of a collection of metric data on the main domestic animals recorded at the University of Southampton, together with the data from some other sources, in particular the Museum of London Archaeology Service (MoLAS). Whilst the data is primarily from England, it is applicable to a wider geographical area. Stored in a neutral archival format, it is freely available for teaching, learning and research.
History of the Project
In the 1990s English Heritage funded a project at the University of Southampton to collect and synthesize metrical data recorded over the past twenty years. The main aim was to assemble the data and ensure that it was kept in a format in which it would be maintained and made accessible.
The Database
The project aimed to collect measurements of the main domestic species found on archaeological sites in England. The database included approximately 25,000 bones, predominantly of cattle and sheep, but also of pig, horse, dog, goat, domestic fowl, and goose. The data set is organized by species, anatomical element, period, and site type.
Sources
Serjeantson, D. (2005). 'Science is Measurement'; ABMAP, a Database of Domestic Animal Bone Measurements. Environmental Archaeology 10 (1): 97-103
External links
ABMAP
Archaeological databases
Zooarchaeology
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https://en.wikipedia.org/wiki/Anal%20plug
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An anal plug (anal tampon or anal insert) is a medical device that is often used to treat fecal incontinence, the accidental passing of bowel moments, by physically blocking involuntary loss of fecal material. Fecal material such as feces are solid remains of food that does not get digested in the small intestines; rather, it is broken down by bacteria in the large intestine. Anal plugs vary in design and composition, but they are typically single-use, intra-anal, disposable devices made out of soft materials to contain fecal material and prevent it from leaking out of the rectum. The idea of an anal insert for fecal incontinence was first evaluated in a study of 10 participants with three different designs of anal inserts.
Use
Populations
Anal plugs may be beneficial to certain risk groups including, but not limited to, frail older people, women following childbirth, people with some neurological or spinal diseases, severe cognitive impairment, urinary incontinence, pelvic organ prolapse, and so on. Typically, anal plugs are used in people whose symptoms do not improve with to typical treatments: this may include changes in diet, physical therapy, nerve stimulation targeting the sacral and tibial nerves, surgical repair of the anus, and utilization of a colostomy bag. Nerve stimulation involves the placement of electrodes near the nerves that travel through a person's hips and down their legs. Colostomy bags are bags that collect feces from their intestines through a surgically created hole on a person's stomach.
Children with certain conditions, including spina bifida and anal atresia, may struggle with leaks even after physical therapy and other interventions, so they may benefit from using anal plugs. Spina bifida is a birth defect where a part of the spinal cord is not surrounded by the vertebrae; either the spinal cord is still in the back, just not surrounded by the vertebral bones, or it can be bulging out in a sac. Anal atresia is another birth defect
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https://en.wikipedia.org/wiki/Edward%20L.%20Sittler%20Jr.
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Edward Lewis Sittler Jr. (April 21, 1908 – December 26, 1978) was a Republican member of the U.S. House of Representatives from Pennsylvania.
Edward Sittler was born in Greensburg, Pennsylvania, and moved with his parents to Uniontown, Pennsylvania while still an infant.
He graduated from Brown University in 1930. He worked as a salesman for an ice cream company from 1931 to 1937. He was elected to the Uniontown School Board in 1934 and served as president of the board in 1936 and 1937. He became a became field underwriter for Mutual Life Insurance Company of New York in 1937. He enlisted as a private in the United States Army in February 1943 and served in the Ordnance Corps in the European Theatre of World War II until released to the Inactive Reserve as a captain in August 1946. He was mayor of Uniontown from 1948 to 1951.
In 1950, he was elected as a Republican to the 82nd United States Congress in the Pennsylvania 23rd district, defeating incumbent Democratic Congressman Anthony Cavalcante, but was an unsuccessful candidate for reelection in 1952 when re-districting forced him into an election against incumbent Democratic Congressman Thomas E. Morgan in the 26th district. He served as Republican State committeeman for Fayette County, Pennsylvania from 1960 to 1972. He was the minority Fayette County Commissioner from 1968 to 1971.
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https://en.wikipedia.org/wiki/Stability%20theory
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In mathematics, stability theory addresses the stability of solutions of differential equations and of trajectories of dynamical systems under small perturbations of initial conditions. The heat equation, for example, is a stable partial differential equation because small perturbations of initial data lead to small variations in temperature at a later time as a result of the maximum principle. In partial differential equations one may measure the distances between functions using Lp norms or the sup norm, while in differential geometry one may measure the distance between spaces using the Gromov–Hausdorff distance.
In dynamical systems, an orbit is called Lyapunov stable if the forward orbit of any point is in a small enough neighborhood or it stays in a small (but perhaps, larger) neighborhood. Various criteria have been developed to prove stability or instability of an orbit. Under favorable circumstances, the question may be reduced to a well-studied problem involving eigenvalues of matrices. A more general method involves Lyapunov functions. In practice, any one of a number of different stability criteria are applied.
Overview in dynamical systems
Many parts of the qualitative theory of differential equations and dynamical systems deal with asymptotic properties of solutions and the trajectories—what happens with the system after a long period of time. The simplest kind of behavior is exhibited by equilibrium points, or fixed points, and by periodic orbits. If a particular orbit is well understood, it is natural to ask next whether a small change in the initial condition will lead to similar behavior. Stability theory addresses the following questions: Will a nearby orbit indefinitely stay close to a given orbit? Will it converge to the given orbit? In the former case, the orbit is called stable; in the latter case, it is called asymptotically stable and the given orbit is said to be attracting.
An equilibrium solution to an autonomous system of first ord
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https://en.wikipedia.org/wiki/Bidiagonalization
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Bidiagonalization is one of unitary (orthogonal) matrix decompositions such that U* A V = B, where U and V are unitary (orthogonal) matrices; * denotes Hermitian transpose; and B is upper bidiagonal. A is allowed to be rectangular.
For dense matrices, the left and right unitary matrices are obtained by a series of Householder reflections alternately applied from the left and right. This is known as Golub-Kahan bidiagonalization. For large matrices, they are calculated iteratively by using Lanczos method, referred to as Golub-Kahan-Lanczos method.
Bidiagonalization has a very similar structure to the singular value decomposition (SVD). However, it is computed within finite operations, while SVD requires iterative schemes to find singular values. The latter is because the squared singular values are the roots of characteristic polynomials of A* A, where A is assumed to be tall.
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https://en.wikipedia.org/wiki/Insurance%20Services%20Office
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Insurance Services Office, Inc. (ISO), a subsidiary of Verisk Analytics, is a provider of statistical, actuarial, underwriting, and claims information and analytics; compliance and fraud identification tools; policy language; information about specific locations; and technical services. ISO serves insurers, reinsurers, agents and brokers, insurance regulators, risk managers, and other participants in the property/casualty insurance marketplace. Headquartered in Jersey City, New Jersey, United States, the organization serves clients with offices throughout the United States, along with international operations offices in the United Kingdom, Israel, Germany, India and China.
Overview
ISO was formed in 1971 as an advisory and rating organization for the property/casualty insurance industry to provide statistical and actuarial services, to develop insurance programs, and to assist insurance companies in meeting state regulatory requirements. It became a wholly owned subsidiary of Verisk Analytics in October 2009.
ISO provides a number of risk-related services to its clients:
Fire and building code information
Insurance lines services
Including standardized text for insurance forms
Collecting the data
Insurance products for agents
Workers' compensation
Medicare compliance and claims resolution services
ISO's databases contain more than 19 billion detailed records relating to insurance and risk management, which form the basis for its information services, with two billion records collected each year. ISO employs many members of the Casualty Actuarial Society and other insurance professionals to develop its risk-related products and services.
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https://en.wikipedia.org/wiki/Stable%20manifold%20theorem
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In mathematics, especially in the study of dynamical systems and differential equations, the stable manifold theorem is an important result about the structure of the set of orbits approaching a given hyperbolic fixed point. It roughly states that the existence of a local diffeomorphism near a fixed point implies the existence of a local stable center manifold containing that fixed point. This manifold has dimension equal to the number of eigenvalues of the Jacobian matrix of the fixed point that are less than 1.
Stable manifold theorem
Let
be a smooth map with hyperbolic fixed point at . We denote by the stable set and by the unstable set of .
The theorem states that
is a smooth manifold and its tangent space has the same dimension as the stable space of the linearization of at .
is a smooth manifold and its tangent space has the same dimension as the unstable space of the linearization of at .
Accordingly is a stable manifold and is an unstable manifold.
See also
Center manifold theorem
Lyapunov exponent
Notes
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https://en.wikipedia.org/wiki/Antagonism%20%28phytopathology%29
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In phytopathology, antagonism refers to the action of any organism that suppresses or interferes with the normal growth and activity of a plant pathogen, such as the main parts of bacteria or fungi.
These organisms can be used for pest control and are referred to as biological control agents. They may be predators, parasites, parasitoids, or pathogens that attack a harmful insect, weed, or plant disease or any other organism in its vicinity. The inhibitory substance is highly specific in its action, affecting only a specific species. Many soil microorganisms are antagonistic. They secrete a potent enzyme which destroys other cells by digesting their cell walls and degrade the cellular material as well as released protoplasmic material serves as a nutrient for the inhibitor organism, for example Aspergillus has an antagonistic effect on Penicillium and Cladosporium. Trichoderma has an effect on actinomycetes. Pseudomonas show antagonism on Cladosporiumsuch organism may be of great practical importance since they often produce antibiotics which modify the normal growth processes.
Mechanism
Antibiosis example — enzymes, toxins, antibiotics.
Direct parasitism example — biotrophic or necrotrophic.
competition example — for nutrients.
Induced resistance (indirect).
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https://en.wikipedia.org/wiki/280%20%28number%29
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280 (two hundred [and] eighty) is the natural number after 279 and before 281.
In mathematics
The denominator of the eighth harmonic number, 280 is an octagonal number. 280 is the smallest octagonal number that is a half of another octagonal number.
There are 280 plane trees with ten nodes.
As a consequence of this, 18 people around a round table can shake hands with each other in non-crossing ways, in 280 different ways (this includes rotations).
Integers from 281 to 289
281
282
283
284
285
286
287
288
289
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https://en.wikipedia.org/wiki/290%20%28number%29
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290 (two hundred [and] ninety) is the natural number following 289 and preceding 291.
In mathematics
The product of three primes, 290 is a sphenic number, and the sum of four consecutive primes (67 + 71 + 73 + 79). The sum of the squares of the divisors of 17 is 290.
Not only is it a nontotient and a noncototient, it is also an untouchable number.
290 is the 16th member of the Mian–Chowla sequence; it can not be obtained as the sum of any two previous terms in the sequence.
See also the Bhargava–Hanke 290 theorem.
Integers from 291 to 299
291
292
293
294
295
296
296 = 23·37, a refactorable number, unique period in base 2, the number of regions formed by drawing the line segments connecting any two of the 12 perimeter points of an 2 times 4 grid of squares (illustration) , and the number of surface points on a 83 cube.
297
297 = 33·11, the number of integer partitions of 17, a decagonal number, and a Kaprekar number
298
298 = 2·149, is nontotient, noncototient, and the number of polynomial symmetric functions of matrix of order 6 under separate row and column permutations
299
299 = 13·23, a highly cototient number, a self number, and the twelfth cake number
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https://en.wikipedia.org/wiki/Kauri-butanol%20value
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The kauri-butanol value ("Kb value") is an international, standardized measure of solvent power for a hydrocarbon solvent, and is governed by an ASTM standardized test, ASTM D1133. The result of this test is a scaleless index, usually referred to as the "Kb value". A higher Kb value means the solvent is more aggressive or active in the ability to dissolve certain materials. Mild solvents have low scores in the tens and twenties; powerful solvents like chlorinated solvents and naphthenic aromatic solvents (i.e. "High Sol 10", "High Sol 15") have ratings that are in the low hundreds.
In terms of the test itself, the kauri-butanol value (Kb) of a chemical shows the maximum amount of the hydrocarbon that can be added to a solution of kauri resin (a thick, gum-like material) in butanol (butyl alcohol) without causing cloudiness. Since kauri resin is readily soluble in butyl alcohol but not in most hydrocarbon solvents, the resin solution will tolerate only a certain amount of dilution. "Stronger" solvents such as benzene can be added in a greater amount (and thus have a higher Kb value) than "weaker" solvents like mineral spirits.
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https://en.wikipedia.org/wiki/Spin%20Hall%20effect
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The spin Hall effect (SHE) is a transport phenomenon predicted by Russian physicists Mikhail I. Dyakonov and Vladimir I. Perel in 1971. It consists of the appearance of spin accumulation on the lateral surfaces of an electric current-carrying sample, the signs of the spin directions being opposite on the opposing boundaries. In a cylindrical wire, the current-induced surface spins will wind around the wire. When the current direction is reversed, the directions of spin orientation is also reversed.
Definition
The spin Hall effect is a transport phenomenon consisting of the appearance of spin accumulation on the lateral surfaces of a sample carrying electric current. The opposing surface boundaries will have spins of opposite sign. It is analogous to the classical Hall effect, where charges of opposite sign appear on the opposing lateral surfaces in an electric-current carrying sample in a magnetic field. In the case of the classical Hall effect the charge build up at the boundaries is in compensation for the Lorentz force acting on the charge carriers in the sample due to the magnetic field. No magnetic field is needed for the spin Hall effect which is a purely spin-based phenomenon. The spin Hall effect belongs to the same family as the anomalous Hall effect, known for a long time in ferromagnets, which also originates from spin–orbit interaction.
History
The spin Hall effect (direct and inverse) was predicted by Russian physicists Mikhail I. Dyakonov and Vladimir I. Perel in 1971. They also introduced for the first time the notion of spin current.
In 1983 Averkiev and Dyakonov proposed a way to measure the inverse spin Hall effect under optical spin orientation in semiconductors. The first experimental demonstration of the inverse spin Hall effect, based on this idea, was performed by Bakun et al. in 1984
The term "spin Hall effect" was introduced by Hirsch who re-predicted this effect in 1999.
Experimentally, the (direct) spin Hall effect was observed i
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https://en.wikipedia.org/wiki/Cyclic%20cellular%20automaton
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A cyclic cellular automaton is a kind of cellular automaton rule developed by David Griffeath and studied by several other cellular automaton researchers. In this system, each cell remains unchanged until some neighboring cell has a modular value exactly one unit larger than that of the cell itself, at which point it copies its neighbor's value. One-dimensional cyclic cellular automata can be interpreted as systems of interacting particles, while cyclic cellular automata in higher dimensions exhibit complex spiraling behavior.
Rules
As with any cellular automaton, the cyclic cellular automaton consists of a regular grid of cells in one or more dimensions. The cells can take on any of states, ranging from to . The first generation starts out with random states in each of the cells. In each subsequent generation, if a cell has a neighboring cell whose value is the successor of the cell's value, the cell is "consumed" and takes on the succeeding value. (Note that is the successor of ; see also modular arithmetic.) More general forms of this type of rule also include a threshold parameter, and only allow a cell to be consumed when the number of neighbors with the successor value exceeds this threshold.
One dimension
The one-dimensional cyclic cellular automaton has been extensively studied by Robert Fisch, a student of Griffeath.
Starting from a random configuration with n = 3 or n = 4, this type of rule can produce a pattern which, when presented as a time-space diagram, shows growing triangles of values competing for larger regions of the grid.
The boundaries between these regions can be viewed as moving particles which collide and interact with each other. In the three-state cyclic cellular automaton, the boundary between regions with values i and i + 1 (mod n) can be viewed as a particle that moves either leftwards or rightwards depending on the ordering of the regions; when a leftward-moving particle collides with a rightward-moving one, they annihilat
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https://en.wikipedia.org/wiki/Kinetic%20resolution
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In organic chemistry, kinetic resolution is a means of differentiating two enantiomers in a racemic mixture. In kinetic resolution, two enantiomers react with different reaction rates in a chemical reaction with a chiral catalyst or reagent, resulting in an enantioenriched sample of the less reactive enantiomer. As opposed to chiral resolution, kinetic resolution does not rely on different physical properties of diastereomeric products, but rather on the different chemical properties of the racemic starting materials. The enantiomeric excess (ee) of the unreacted starting material continually rises as more product is formed, reaching 100% just before full completion of the reaction. Kinetic resolution relies upon differences in reactivity between enantiomers or enantiomeric complexes.
Kinetic resolution can be used for the preparation of chiral molecules in organic synthesis. Kinetic resolution reactions utilizing purely synthetic reagents and catalysts are much less common than the use of enzymatic kinetic resolution in application towards organic synthesis, although a number of useful synthetic techniques have been developed in the past 30 years.
History
The first reported kinetic resolution was achieved by Louis Pasteur. After reacting aqueous racemic ammonium tartrate with a mold from Penicillium glaucum, he reisolated the remaining tartrate and found it was levorotatory. The chiral microorganisms present in the mold catalyzed the metabolization of (R,R)-tartrate selectively, leaving an excess of (S,S)-tartrate.
Kinetic resolution by synthetic means was first reported by Marckwald and McKenzie in 1899 in the esterification of racemic mandelic acid with optically active (−)-menthol. With an excess of the racemic acid present, they observed the formation of the ester derived from (+)-mandelic acid to be quicker than the formation of the ester from (−)-mandelic acid. The unreacted acid was observed to have a slight excess of (−)-mandelic acid, and the ester wa
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https://en.wikipedia.org/wiki/Check%20Point%20Integrity
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Check Point Integrity is an endpoint security software product developed by Check Point Software Technologies. It is designed to protect personal computers and the networks they connect to from computer worms, Trojan horses, spyware, and intrusion attempts by hackers. The software aims to stop new PC threats and attacks before signature updates have been installed on the PC. The software includes.
network access controls that detect and remedy security policy violations before a PC is allowed to connect to a network;
application controls that block or terminate malicious software programs before they can transmit information to an unauthorized party;
a personal firewall;
an intrusion prevention system (IPS) Check Point Intrusion Prevention System – IPS;
spyware detection and removal;
and instant messaging security tools.
An administrator manages the security policies that apply to groups of users from a central console and server.
Check Point acquired the Integrity software as part of its acquisition of endpoint security start-up Zone Labs in 2004. The Integrity software, released in early 2002, was derived from the ZoneAlarm security technology and added central policy management and network access control functions. Integrity was integrated with network gateways (the Cisco VPN 3000 series) to ensure that a PC met security requirements before it was granted access to the network.
Demand for endpoint security grew in 2003 after the SQL Slammer and Blaster computer worms reportedly caused extensive damage, despite widespread use of antivirus software on personal computers. A number of destructive worms that followed, and the subsequent rise of spyware as a significant problem, continued to increase demand for endpoint security products. Data privacy and integrity regulations and required security audits mandated by governmental and professional authorities, along with infections and damage caused by guest PC access, have also prompted use of such security sof
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https://en.wikipedia.org/wiki/Cell%20software%20development
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Software development for the Cell microprocessor involves a mixture of conventional development practices for the PowerPC-compatible PPU core, and novel software development challenges with regard to the functionally reduced SPU coprocessors.
Linux on Cell
An open source software-based strategy was adopted to accelerate the development of a Cell BE ecosystem and to provide an environment to develop Cell applications, including a GCC-based Cell compiler, binutils and a port of the Linux operating system.
Octopiler
Octopiler is IBM's prototype compiler to allow software developers to write code for Cell processors.
Software portability
Adapting VMX for SPU
Differences between VMX and SPU
The VMX (Vector Multimedia Extensions) technology is conceptually similar to the vector model provided by the SPU processors, but there are many significant differences.
The VMX Java mode conforms to the Java Language Specification 1 subset of the default IEEE Standard, extended to include IEEE and C9X compliance where the Java standard falls silent. In a typical implementation, non-Java mode converts denormal values to zero but Java mode traps into an emulator when the processor encounters such a value.
The IBM PPE Vector/SIMD manual does not define operations for double-precision floating point, though IBM has published material implying certain double-precision performance numbers associated with the Cell PPE VMX technology.
Intrinsics
Compilers for Cell provide intrinsics to expose useful SPU instructions in C and C++. Instructions that differ only in the type of operand (such as a, ai, ah, ahi, fa, and dfa for addition) are typically represented by a single C/C++ intrinsic which selects the proper instruction based on the type of the operand.
Porting VMX code for SPU
There is a great body of code which has been developed for other IBM Power microprocessors that could potentially be adapted and recompiled to run on the SPU. This code base includes VMX code that runs under
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https://en.wikipedia.org/wiki/Power%20dividers%20and%20directional%20couplers
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Power dividers (also power splitters and, when used in reverse, power combiners) and directional couplers are passive devices used mostly in the field of radio technology. They couple a defined amount of the electromagnetic power in a transmission line to a port enabling the signal to be used in another circuit. An essential feature of directional couplers is that they only couple power flowing in one direction. Power entering the output port is coupled to the isolated port but not to the coupled port. A directional coupler designed to split power equally between two ports is called a hybrid coupler.
Directional couplers are most frequently constructed from two coupled transmission lines set close enough together such that energy passing through one is coupled to the other. This technique is favoured at the microwave frequencies where transmission line designs are commonly used to implement many circuit elements. However, lumped component devices are also possible at lower frequencies, such as the audio frequencies encountered in telephony. Also at microwave frequencies, particularly the higher bands, waveguide designs can be used. Many of these waveguide couplers correspond to one of the conducting transmission line designs, but there are also types that are unique to waveguide.
Directional couplers and power dividers have many applications. These include providing a signal sample for measurement or monitoring, feedback, combining feeds to and from antennas, antenna beam forming, providing taps for cable distributed systems such as cable TV, and separating transmitted and received signals on telephone lines.
Notation and symbols
The symbols most often used for directional couplers are shown in figure 1. The symbol may have the coupling factor in dB marked on it. Directional couplers have four ports. Port 1 is the input port where power is applied. Port 3 is the coupled port where a portion of the power applied to port 1 appears. Port 2 is the transm
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https://en.wikipedia.org/wiki/Rothenberg%20propriety
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In diatonic set theory, Rothenberg propriety is an important concept, lack of contradiction and ambiguity, in the general theory of musical scales which was introduced by David Rothenberg in a seminal series of papers in 1978. The concept was independently discovered in a more restricted context by Gerald Balzano, who termed it coherence.
"Rothenberg calls a scale 'strictly proper' if it possesses a generic ordering, 'proper' if it admits ambiguities but no contradictions, and 'improper' if it admits contradictions." A scale is strictly proper if all two step intervals are larger than any one step interval, all three step intervals are larger than any two step interval and so on. For instance with the diatonic scale, the one step intervals are the semitone (1) and tone (2), the two step intervals are the minor (3) and major (4) third, the three step intervals are the fourth (5) and tritone (6), the four step intervals are the fifth (7) and tritone (6), the five step intervals are the minor (8) and major (9) sixth, and the six step intervals are the minor (t) and major (e) seventh. So it's not strictly proper because the three step intervals and the four step intervals share an interval size (the tritone), causing ambiguity ("two [specific] intervals, that sound the same, map onto different codes [general intervals]"). Such a scale is just called "proper".
For example, the major pentatonic scale is strictly proper:
The pentatonic scales which are proper, but not strictly, are:
{0,1,4,6,8} (Lydian chord)
{0,2,4,6,8} (whole tone scale)
{0,1,4,6,9} (gamma chord)
{0,2,4,6,9} (dominant ninth chord)
{0,1,3,6,9} (dominant minor ninth chord)
The one strictly proper pentatonic scale:
{0,2,4,7,9} (major pentatonic)
The heptatonic scales which are proper, but not strictly, are:
{0,1,3,4,6,8,9} (harmonic minor scale)
{0,1,3,5,6,8,t} (diatonic scale)
{0,1,3,4,6,8,t} (Altered scale)
{0,1,2,4,6,8,t} (Major Neapolitan scale)
Propriety may also be considered as scales whose stabi
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https://en.wikipedia.org/wiki/Cell%20microprocessor%20implementations
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Cell microprocessors are multi-core processors that use cellular architecture for high performance distributed computing. The first commercial Cell microprocessor, the Cell BE, was designed for the Sony PlayStation 3. IBM designed the PowerXCell 8i for use in the Roadrunner supercomputer.
Implementation
First edition Cell on 90 nm CMOS
IBM has published information concerning two different versions of Cell in this process, an early engineering sample designated DD1, and an enhanced version designated DD2 intended for production.
The main enhancement in DD2 was a small lengthening of the die to accommodate a larger PPE core, which is reported to "contain more SIMD/vector execution resources".
Some preliminary information released by IBM references the DD1 variant. As a result, some early journalistic accounts of the Cell's capabilities now differ from production hardware.
Cell floorplan
Powerpoint material accompanying an STI presentation given by Dr Peter Hofstee], includes a photograph of the DD2 Cell die overdrawn with functional unit boundaries which are also captioned by name, which reveals the breakdown of silicon area by function unit as follows:
SPE floorplan
Additional details concerning the internal SPE implementation have been disclosed by IBM engineers, including Peter Hofstee, IBM's chief architect of the synergistic processing element, in a scholarly IEEE publication.
This document includes a photograph of the 2.54 mm × 5.81 mm SPE, as implemented in 90-nm SOI. In this technology, the SPE contains 21 million transistors of which 14 million are contained in arrays (a term presumably designating register files and the local store) and 7 million transistors are logic. This photograph is overdrawn with functional unit boundaries, which are also captioned by name, which reveals the breakdown of silicon area by function unit as follows:
Understanding the dispatch pipes is important to write efficient code. In the SPU architecture, two instructions c
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https://en.wikipedia.org/wiki/Current%20density
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In electromagnetism, current density is the amount of charge per unit time that flows through a unit area of a chosen cross section. The current density vector is defined as a vector whose magnitude is the electric current per cross-sectional area at a given point in space, its direction being that of the motion of the positive charges at this point. In SI base units, the electric current density is measured in amperes per square metre.
Definition
Assume that (SI unit: m2) is a small surface centred at a given point and orthogonal to the motion of the charges at . If (SI unit: A) is the electric current flowing through , then electric current density at is given by the limit:
with surface remaining centered at and orthogonal to the motion of the charges during the limit process.
The current density vector is the vector whose magnitude is the electric current density, and whose direction is the same as the motion of the positive charges at .
At a given time , if is the velocity of the charges at , and is an infinitesimal surface centred at and orthogonal to , then during an amount of time , only the charge contained in the volume formed by and will flow through . This charge is equal to where is the charge density at . The electric current is , it follows that the current density vector is the vector normal (i.e. parallel to ) and of magnitude
The surface integral of over a surface , followed by an integral over the time duration to , gives the total amount of charge flowing through the surface in that time ():
More concisely, this is the integral of the flux of across between and .
The area required to calculate the flux is real or imaginary, flat or curved, either as a cross-sectional area or a surface. For example, for charge carriers passing through an electrical conductor, the area is the cross-section of the conductor, at the section considered.
The vector area is a combination of the magnitude of the area through which the charge
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https://en.wikipedia.org/wiki/Bridge%20management%20system
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A bridge management system (BMS) is a set of methodologies and procedures for managing information about bridges. Such system is capable of document and process data along the entire life cycle of the structure steps: project design, construction, monitoring, maintenance and end of operation.
First used in literature in 1987, the acronym BMS is commonly used in structural engineering to refer to a single or a combination of digital tools and software that support the documentation of every practice related to the single structure. Such software architecture has to meet the needs of road asset managers interested on tracking the serviceability status of bridges through a workflow mainly based on 4 components: data inventory, cost and construction management, structural analysis and assessment and maintenance planning. The implementation of BMS usually is built on top of relational databases, geographic information systems (GIS) and building information modeling platform (BIM) also named bridge information modeling (BrIM) with photogrammetric and laser scanning processing software used for the management of data collected during targeted inspections. The output of the whole procedure, as stated also in some national guidelines of different countries, usually consists of a prioritization of intervention on bridges classified in different risk level according to information collected and processed.
History
Since the late 1980s the structural health assessment and monitoring of bridges represented a critical topic in the field of civil infrastructure management. In the 1990s, the Federal Highway Administration (FHWA) of the United States promoted and sponsored PONTIS and BRIDGEIT, two computerized platforms for viaduct inventory and monitoring named BMSs. In the following years, also outside the U.S., the growing need of an organized and digitized road asset management has led responsible national agencies to adopt increasingly complex solutions able to meet their obj
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https://en.wikipedia.org/wiki/Letterlike%20Symbols
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Letterlike Symbols is a Unicode block containing 80 characters which are constructed mainly from the glyphs of one or more letters. In addition to this block, Unicode includes full styled mathematical alphabets, although Unicode does not explicitly categorize these characters as being "letterlike."
Symbols
Glyph variants
Variation selectors may be used to specify chancery (U+FE00) vs roundhand (U+FE01) forms, if the font supports them:
The remainder of the set is at Mathematical Alphanumeric Symbols.
Block
Emoji
The Letterlike Symbols block contains two emoji:
U+2122 and U+2139.
The block has four standardized variants defined to specify emoji-style (U+FE0F VS16) or text presentation (U+FE0E VS15) for the
two emoji, both of which default to a text presentation.
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Letterlike Symbols block:
See also
Greek in Unicode
Latin script in Unicode
Unicode symbols
Mathematical operators and symbols in Unicode
Mathematical Alphanumeric Symbols (Unicode block)
Currency Symbols (Unicode block)
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https://en.wikipedia.org/wiki/Desmoglein
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The desmogleins are a family of desmosomal cadherins consisting of proteins DSG1, DSG2, DSG3, and DSG4. They play a role in the formation of desmosomes that join cells to one another.
Pathology
Desmogleins are targeted in the autoimmune disease pemphigus.
Desmoglein proteins are a type of cadherin, which is a transmembrane protein that binds with other cadherins to form junctions known as desmosomes between cells. These desmoglein proteins thus hold cells together, but, when the body starts producing antibodies against desmoglein, these junctions break down, and this results in subsequent blister or vesicle formation.
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https://en.wikipedia.org/wiki/Matching%20law
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In operant conditioning, the matching law is a quantitative relationship that holds between the relative rates of response and the relative rates of reinforcement in concurrent schedules of reinforcement. For example, if two response alternatives A and B are offered to an organism, the ratio of response rates to A and B equals the ratio of reinforcements yielded by each response. This law applies fairly well when non-human subjects are exposed to concurrent variable interval schedules (but see below); its applicability in other situations is less clear, depending on the assumptions made and the details of the experimental situation. The generality of applicability of the matching law is subject of current debate.
The matching law can be applied to situations involving a single response maintained by a single schedule of reinforcement if one assumes that alternative responses are always available to an organism, maintained by uncontrolled "extraneous" reinforcers. For example, an animal pressing a lever for food might pause for a drink of water.
The matching law was first formulated by R.J. Herrnstein (1961) following an experiment with pigeons on concurrent variable interval schedules. Pigeons were presented with two buttons in a Skinner box, each of which led to varying rates of food reward. The pigeons tended to peck the button that yielded the greater food reward more often than the other button, and the ratio of their rates to the two buttons matched the ratio of their rates of reward on the two buttons.
Mathematical statement
If R and R are the rate of responses on two schedules that yield obtained (as distinct from programmed) rates of reinforcement Rf and Rf, the strict matching law holds that the relative response rate R / (R + R) matches, that is, equals, the relative reinforcement rate Rf / (Rf + Rf). That is,
This relationship can also be stated in terms of response and reinforcement ratios:
Alternatively stated, it states that there exists a const
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https://en.wikipedia.org/wiki/NUTS%20statistical%20regions%20of%20Hungary
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The NUTS codes of Hungary have three levels:
Codes
Local administrative units
Below the NUTS levels, the two LAU (Local Administrative Units) levels are:
The LAU codes of Hungary can be downloaded here:
Changes in NUTS 2016 classification
The NUTS classification is regularly updated to reflect changes and modifications proposed by Member States. As part of this process the European Commission has adopted changes concerning Hungary in December 2016. The new classification that has been introduced have split the region Central Hungary in two: Budapest (previously HU101) and Pest county (previously HU102). The new classification is in use since 1 January 2018.
See also
ISO 3166-2 codes of Hungary
FIPS region codes of Hungary
Regions of Hungary
Counties of Hungary
Districts of Hungary (from 2013)
Subregions of Hungary (until 2013)
Administrative divisions of the Kingdom of Hungary (until 1918)
Counties of the Kingdom of Hungary
Administrative divisions of the Kingdom of Hungary (1941–44)
List of cities and towns of Hungary
Sources
Hierarchical list of the Nomenclature of territorial units for statistics - NUTS and the Statistical regions of Europe
Overview map of EU Countries - NUTS level 1
MAGYARORSZÁG - NUTS level 2
MAGYARORSZÁG - NUTS level 3
Correspondence between the NUTS levels and the national administrative units
List of current NUTS codes
Download current NUTS codes (ODS format)
Counties of Hungary, Statoids.com
External links
Eurostat - Portrait of the regions (forum.europa.eu.int)
Comparative analysis of some Hungarian regions by using “COCO” method (DOC file) (HTML version)
Magyarország – NUTS level 3 (PDF; at the website of the Hungarian Prime Minister's Office )
Regions of Hungary (at Hungary.hu, the Government Portal of Hungary)
Hungary and the regions
Hungary
Nuts
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https://en.wikipedia.org/wiki/Soil%20production%20function
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Soil production function refers to the rate of bedrock weathering into soil as a function of soil thickness.
A general model suggested that the rate of physical weathering of bedrock (de/dt) can be represented as an exponential decline with soil thickness:
where h is soil thickness [m], P0 [mm/year] is the potential (or maximum) weathering rate of bedrock and k [m−1] is an empirical constant.
The reduction of weathering rate with thickening of soil is related to the exponential decrease of temperature amplitude with increasing depth below the soil surface, and also the exponential decrease in average water penetration (for freely-drained soils). Parameters P0 and k are related to the climate and type of parent materials. found the value of P0 ranges from 0.08 to 2.0 mm/yr for sites in Northern California, and 0.05–0.14 mm/yr for sites in Southeastern Australia. Meanwhile values of k do not vary significantly, ranging from 2 to 4 m−1.
A number of landscape evolution models have adopted the so-called humped model. This model dates back to G.K. Gilbert's Report on the Geology of the Henry Mountains (1877). Gilbert reasoned that the weathering of bedrock was fastest under an intermediate thickness of soil and slower under exposed bedrock or under thick mantled soil. This is because chemical weathering requires the presence of water. Under thin soil or exposed bedrock water tends to run off, reducing the chance of the decomposition of bedrock.
See also
Biorhexistasy
Hillslope evolution
Parent material
Pedogenesis
Soil functions
Weathering
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https://en.wikipedia.org/wiki/Fumonisin
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The fumonisins are a group of mycotoxins derived from Fusarium and their Liseola section. They have strong structural similarity to sphinganine, the backbone precursor of sphingolipids.
More specifically, it can refer to:
Fumonisin B1
Fumonisin B2
Fumonisin B3
Fumonisin B4
As the fumonisins appear to be non-genotoxic the possibility that they belong to another class of non-genotoxic carcinogens, the peroxisome proliferators, was investigated
Genetic engineering is reported as a promising means of detoxifying mycotoxins. This approach may provide innovative solutions to the problem of fumonisin in corn.
At least 15 different fumonisins have so far been reported and other minor metabolites have been identified, although most of them have not been shown to occur naturally. In 2015, a unique class of non-aminated fumonisins was reported on grapes infected with Aspergillus welwitschiae, although their toxicities have not yet been established.
Other Fusarium toxins
The trichothecene (T-2) mycotoxins are a group of over 40 compounds produced by fungi of the genus Fusarium, a common grain mold.
The estrogenic metabolite, zearalenone, is also referred to as F-2 toxin.
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https://en.wikipedia.org/wiki/Sensient%20Technologies
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Sensient Technologies is a global manufacturer and marketer of colors, flavors and fragrances based in Milwaukee, Wisconsin. Their products are used in many foods and beverages, pharmaceuticals, cosmetics, home and personal care products, specialty printing and imaging products, computer imaging and industrial colors. Sensient reported revenue of $1,468 million in 2013. Subdivisions include the Sensient Flavors & Fragrances Group and the Sensient Color Group. Within the Flavors & Fragrances Group is Sensient Natural Ingredients. In 2021, Sensient was ranked 10th on the Global Top 50 Food Flavors and Fragrances Companies list.
History
Sensient Technologies was founded in 1882 as Meadow Springs Distilling Company. In the late 19th century, the company changed its name to National Distilling Company. By 1919 the company was threatened by prohibition but by then it had created a business selling yeast under the Red Star Yeast brand. Accordingly, the company changed its name to Red Star Yeast and Products Company.
By the 1960s, the company had become a highly diversified food company and changed its name again to Universal Foods Corporation. In 1977 the company listed its stock on the New York Stock Exchange (SXT).
In 1984 Sensient acquired Warner-Jenkinson Co. (color applications). Together with some other acquisitions this developed into the cosmetic color division. This division is now called 'Sensient Cosmetic Technologies'.
Kenneth P. Manning, Sensient Technologies' Chairman and CEO, joined the company in 1987 as Group Vice President. When Manning was named CEO of Universal Foods in 1996, he accelerated its expansion by making strategic acquisitions. Since 1997, the corporation has acquired 20 companies.
In 2000 Universal Foods changed its name to Sensient Technologies Corporation. Following this name change, Sensient sold Red Star Yeast in 2001.
Sensient Natural Ingredients received Non-GMO Project Verification for its California-grown garlic, onion and pars
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https://en.wikipedia.org/wiki/Zero-order%20hold
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The zero-order hold (ZOH) is a mathematical model of the practical signal reconstruction done by a conventional digital-to-analog converter (DAC). That is, it describes the effect of converting a discrete-time signal to a continuous-time signal by holding each sample value for one sample interval. It has several applications in electrical communication.
Time-domain model
A zero-order hold reconstructs the following continuous-time waveform from a sample sequence x[n], assuming one sample per time interval T:
where is the rectangular function.
The function is depicted in Figure 1, and is the piecewise-constant signal depicted in Figure 2.
Frequency-domain model
The equation above for the output of the ZOH can also be modeled as the output of a linear time-invariant filter with impulse response equal to a rect function, and with input being a sequence of dirac impulses scaled to the sample values. The filter can then be analyzed in the frequency domain, for comparison with other reconstruction methods such as the Whittaker–Shannon interpolation formula suggested by the Nyquist–Shannon sampling theorem, or such as the first-order hold or linear interpolation between sample values.
In this method, a sequence of Dirac impulses, xs(t), representing the discrete samples, x[n], is low-pass filtered to recover a continuous-time signal, x(t).
Even though this is not what a DAC does in reality, the DAC output can be modeled by applying the hypothetical sequence of dirac impulses, xs(t), to a linear, time-invariant filter with such characteristics (which, for an LTI system, are fully described by the impulse response) so that each input impulse results in the correct constant pulse in the output.
Begin by defining a continuous-time signal from the sample values, as above but using delta functions instead of rect functions:
The scaling by , which arises naturally by time-scaling the delta function, has the result that the mean value of xs(t) is equal to the mean v
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https://en.wikipedia.org/wiki/Peter%20Samson
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Peter R. Samson (born 1941 in Fitchburg, Massachusetts) is an American computer scientist, best known for creating pioneering computer software for the TX-0 and PDP-1.
Samson studied at the Massachusetts Institute of Technology (MIT) between 1958-1963. He wrote, with characteristic wit, the first editions of the Tech Model Railroad Club (TMRC) dictionary, a predecessor to the Jargon File. He appears in Hackers: Heroes of the Computer Revolution by Steven Levy.
Career
The Tech Model Railroad Club
As a member of the Tech Model Railroad Club in his student days at MIT, Samson was noted for his contributions to the Signals and Power Subcommittee, the technical side of the club. Steven Levy's Hackers: Heroes of the Computer Revolution outlines Samson's interest in trains and electronics, and his influence in the club. Levy explains how the club was in fact Samson's gateway into hacking and his ability to manipulate electronics and machine code to create programs. Levy explains how Samson discovered his programming passion with the IBM 704, but frustration with the high level of security around the machine. Only those with very high clearance were able to actually handle the computer, with all programs submitted to be processed through the machine by someone else. This meant Samson would not find out the results of his programs until a few days after submitting them. Because of these restrictions to the IBM 704, it was not until Samson was introduced to the TX-0 that he could explore his obsession with computer programming, as members of the Railroad Club were able to access the computer directly without having to go through a superior.
Dawn of software
Working with Jack Dennis on the TX-0 at MIT Building 26, he developed an interest in computing waveforms to synthesize music. For the PDP-1 he wrote the Harmony Compiler with which PDP-1 users coded music.
He wrote the Expensive Planetarium star display for Spacewar!.
Also for the PDP-1 he wrote TJ-2 (Type Justify
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https://en.wikipedia.org/wiki/Carry%20flag
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In computer processors the carry flag (usually indicated as the C flag) is a single bit in a system status register/flag register used to indicate when an arithmetic carry or borrow has been generated out of the most significant arithmetic logic unit (ALU) bit position. The carry flag enables numbers larger than a single ALU width to be added/subtracted by carrying (adding) a binary digit from a partial addition/subtraction to the least significant bit position of a more significant word. This is typically programmed by the user of the processor on the assembly or machine code level, but can also happen internally in certain processors, via digital logic or microcode, where some processors have wider registers and arithmetic instructions than (combinatorial, or "physical") ALU. It is also used to extend bit shifts and rotates in a similar manner on many processors (sometimes done via a dedicated flag). For subtractive operations, two (opposite) conventions are employed as most machines set the carry flag on borrow while some machines (such as the 6502 and the PIC) instead reset the carry flag on borrow (and vice versa).
Uses
The carry flag is affected by the result of most arithmetic (and typically several bit wise) instructions and is also used as an input to many of them. Several of these instructions have two forms which either read or ignore the carry. In assembly languages these instructions are represented by mnemonics such as ADD/SUB, ADC/SBC (ADD/SUB including carry), SHL/SHR (bit shifts), ROL/ROR (bit rotates), RCR/RCL (rotate through carry), and so on. The use of the carry flag in this manner enables multi-word add, subtract, shift, and rotate operations.
An example is what happens if one were to add 255 and 255 using 8-bit registers. The result should be 510 which is the 9-bit value 111111110 in binary. The 8 least significant bits always stored in the register would be 11111110 binary (254 decimal) but since there is carry out of bit 7 (the eight bit)
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https://en.wikipedia.org/wiki/Parity%20flag
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In computer processors the parity flag indicates if the numbers of set bits is odd or even in the binary representation of the result of the last operation. It is normally a single bit in a processor status register.
For example, assume a machine where a set parity flag indicates even parity. If the result of the last operation were 26 (11010 in binary), the parity flag would be 0 since the number of set bits is odd. Similarly, if the result were 10 (1010 in binary) then the parity flag would be 1.
x86 processors
In x86 processors, the parity flag reflects the parity only of the least significant byte of the result, and is set if the number of set bits of ones is even (put another way, the parity bit is set if the sum of the bits is even). According to 80386 Intel manual, the parity flag is changed in the x86 processor family by the following instructions:
All arithmetic instructions;
Compare instruction (equivalent to a subtract instruction without storing the result);
Logical instructions - XOR, AND, OR;
the TEST instruction (equivalent to the AND instruction without storing the result).
the POPF instruction
the IRET instruction
an instruction or interrupt that causes a hardware task switch
In conditional jumps, parity flag is used, where e.g. the JP instruction jumps to the given target when the parity flag is set and the JNP instruction jumps if it is not set. The flag may be also read directly with instructions such as PUSHF, which pushes the flags register on the stack.
One common reason to test the parity flag is to check an unrelated x87-FPU flag. The FPU has four condition flags (C0 to C3), but they can not be tested directly, and must instead be first copied to the flags register. When this happens, C0 is placed in the carry flag, C2 in the parity flag and C3 in the zero flag. The C2 flag is set when e.g. incomparable floating point values (NaN or unsupported format) are compared with the FUCOM instructions.
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https://en.wikipedia.org/wiki/Negative%20flag
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In a computer processor the negative flag or sign flag is a single bit in a system status (flag) register used to indicate whether the result of the last mathematical operation produced a value in which the most significant bit (the left most bit) was set. In a two's complement interpretation of the result, the negative flag is set if the result was negative.
For example, in an 8-bit signed number system, -37 will be represented as 1101 1011 in binary (the most significant bit, or sign bit, is 1), while +37 will be represented as 0010 0101 (the most significant bit is 0).
The negative flag is set according to the result in the x86 series processors by the following instructions (referring to the Intel 80386 manual):
All arithmetic operations except multiplication and division;
compare instructions (equivalent to subtract instructions without storing the result);
Logical instructions – XOR, AND, OR;
TEST instructions (equivalent to AND instructions without storing the result).
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https://en.wikipedia.org/wiki/Duality%20%28electrical%20circuits%29
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In electrical engineering, electrical terms are associated into pairs called duals. A dual of a relationship is formed by interchanging voltage and current in an expression. The dual expression thus produced is of the same form, and the reason that the dual is always a valid statement can be traced to the duality of electricity and magnetism.
Here is a partial list of electrical dualities:
voltage – current
parallel – serial (circuits)
resistance – conductance
voltage division – current division
impedance – admittance
capacitance – inductance
reactance – susceptance
short circuit – open circuit
Kirchhoff's current law – Kirchhoff's voltage law.
Thévenin's theorem – Norton's theorem
History
The use of duality in circuit theory is due to Alexander Russell who published his ideas in 1904.
Examples
Constitutive relations
Resistor and conductor (Ohm's law)
Capacitor and inductor – differential form
Capacitor and inductor – integral form
Voltage division — current division
Impedance and admittance
Resistor and conductor
Capacitor and inductor
See also
Duality (electricity and magnetism)
Duality (mechanical engineering)
Dual impedance
Dual graph
Mechanical–electrical analogies
List of dualities
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https://en.wikipedia.org/wiki/VTun
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VTun is a networking application which can set up Virtual Tunnels over TCP/IP networks. It supports Internet Protocol (IP), Point-to-Point Protocol (PPP) and Serial Line Internet Protocol (SLIP) protocols. It exists as the reference implementation of the Tun/Tap user-space tunnel driver which was included in the Linux kernel as of version 2.4, also originally developed by Maxim Krasnyansky. Bishop Clark is the current maintainer.
Networking
Like most other applications of its nature, VTun creates a single connection between two machines, over which it multiplexes all traffic. VTun connections are initiated via a TCP connection from the client to the server. The server then initiates a UDP connection to the client, if the UDP protocol is requested.
The software allows the creation of tunnels, for routing traffic in a manner similar to PPP, as well as a bridge-friendly ethertap connection.
Authentication
VTun uses a Private Shared Key to negotiate a handshake via a challenge and response.
Non-encrypting versions
A continual source of concern, and the target of more than one strongly worded security assessment, is that the VTun server and client binary applications can be completely built without encryption support. When such binaries are used, the encryption between both endpoints is only a simple XOR cipher, which is completely trivial to decode. This type of build is not supported by the developers.
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https://en.wikipedia.org/wiki/Number%20Forms
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Number Forms is a Unicode block containing Unicode compatibility characters that have specific meaning as numbers, but are constructed from other characters. They consist primarily of vulgar fractions and Roman numerals. In addition to the characters in the Number Forms block, three fractions (¼, ½, and ¾) were inherited from ISO-8859-1, which was incorporated whole as the Latin-1 Supplement block.
List of characters
Block
History
The following Unicode-related documents record the purpose and process of defining specific characters in the Number Forms block:
See also
Latin script in Unicode
Unicode symbols
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https://en.wikipedia.org/wiki/DNA%20repair-deficiency%20disorder
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A DNA repair-deficiency disorder is a medical condition due to reduced functionality of DNA repair.
DNA repair defects can cause an accelerated aging disease or an increased risk of cancer, or sometimes both.
DNA repair defects and accelerated aging
DNA repair defects are seen in nearly all of the diseases described as accelerated aging disease, in which various tissues, organs or systems of the human body age prematurely. Because the accelerated aging diseases display different aspects of aging, but never every aspect, they are often called segmental progerias by biogerontologists.
Human disorders with accelerated aging
Ataxia-telangiectasia
Bloom syndrome
Cockayne syndrome
Fanconi anemia
Progeria (Hutchinson–Gilford progeria syndrome)
Rothmund–Thomson syndrome
Trichothiodystrophy
Werner syndrome
Xeroderma pigmentosum
Examples
Some examples of DNA repair defects causing progeroid syndromes in humans or mice are shown in Table 1.
DNA repair defects distinguished from "accelerated aging"
Most of the DNA repair deficiency diseases show varying degrees of "accelerated aging" or cancer (often some of both). But elimination of any gene essential for base excision repair kills the embryo—it is too lethal to display symptoms (much less symptoms of cancer or "accelerated aging").
Rothmund-Thomson syndrome and xeroderma pigmentosum display symptoms dominated by vulnerability to cancer, whereas progeria and Werner syndrome show the most features of "accelerated aging". Hereditary nonpolyposis colorectal cancer (HNPCC) is very often caused by a defective MSH2 gene leading to defective mismatch repair, but displays no symptoms of "accelerated aging". On the other hand, Cockayne Syndrome and trichothiodystrophy show mainly features of accelerated aging, but apparently without an increased risk of cancer Some DNA repair defects manifest as neurodegeneration rather than as cancer or "accelerated aging". (Also see the "DNA damage theory of aging" for a discussion of the e
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https://en.wikipedia.org/wiki/Ionotropic%20glutamate%20receptor
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Ionotropic glutamate receptors (iGluRs) are ligand-gated ion channels that are activated by the neurotransmitter glutamate. They mediate the majority of excitatory synaptic transmission throughout the central nervous system and are key players in synaptic plasticity, which is important for learning and memory. iGluRs have been divided into four subtypes on the basis of their ligand binding properties (pharmacology) and sequence similarity: AMPA receptors, kainate receptors, NMDA receptors and delta receptors (see below).
AMPA receptors are the main charge carriers during basal transmission, permitting influx of sodium ions to depolarise the postsynaptic membrane. NMDA receptors are blocked by magnesium ions and therefore only permit ion flux following prior depolarisation. This enables them to act as coincidence detectors for synaptic plasticity. Calcium influx through NMDA receptors leads to persistent modifications in the strength of synaptic transmission.
iGluRs are tetramers (they are formed of four subunits). All subunits have a shared architecture with four domain layers: two extracellular clamshell domains called the N-terminal domain (NTD) and ligand-binding domain (LBD; which binds glutamate), the transmembrane domain (TMD) that forms the ion channel, and an intracellular C-terminal domain (CTD).
Human proteins/genes encoding iGluR subunits
AMPA receptors: GluA1/GRIA1; GluA2/GRIA2; GluA3/GRIA3; GluA4/GRIA4;
delta receptors: GluD1/GRID1; GluD2/GRID2;
kainate receptors: GluK1/GRIK1; GluK2/GRIK2; GluK3/GRIK3; GluK4/GRIK4; GluK5/GRIK5;
NMDA receptors: GluN1/GRIN1; GluN2A/GRIN2A; GluN2B/GRIN2B; GluN2C/GRIN2C; GluN2D/GRIN2D; GluN3A/GRIN3A; GluN3B/GRIN3B;
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https://en.wikipedia.org/wiki/11%CE%B2-Hydroxysteroid%20dehydrogenase%20type%201
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11β-Hydroxysteroid dehydrogenase type 1, also known as cortisone reductase, is an NADPH-dependent enzyme highly expressed in key metabolic tissues including liver, adipose tissue, and the central nervous system. In these tissues, HSD11B1 reduces cortisone to the active hormone cortisol that activates glucocorticoid receptors. It belongs to the family of short-chain dehydrogenases. It is encoded by the gene.
Function
The protein encoded by this gene is a microsomal enzyme that catalyzes the conversion of the stress hormone cortisol to the inactive metabolite cortisone. In addition, the encoded protein can catalyze the reverse reaction, the conversion of cortisone to cortisol. Too much cortisol can lead to central obesity, and a particular variation in this gene has been associated with obesity and insulin resistance in children. Two transcript variants encoding the same protein have been found for this gene.
Clinical significance
11β-HSD1 is inhibited by carbenoxolone, a drug typically used in the treatment of peptic ulcers. Moreover, 18alpha-glycyrrhizic acid from the root of glycyrrhiza glabra was discovered as an inhibitor.
Salicylate downregulates 11β-HSD1 expression in adipose tissue in obese mice and hence may explain why aspirin improves glycemic control in type 2 diabetes. Epigallocatechin gallate from green tea can also potently inhibit this enzyme; green tea is a complex mixture of various phenolics with contents varying with production and processing, and some of the phenolics are known HDAC inhibitors that alter genetic expression. EGCG as usually consumed in green tea is poorly absorbed into the bloodstream. More research is needed to reach firm conclusions.
See also
Cortisone reductase deficiency
11β-hydroxysteroid dehydrogenase type 2
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https://en.wikipedia.org/wiki/Kaliuresis
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Kaliuresis () or kaluresis () is the condition of excreting potassium in the urine.
Thiazide diuretics are used to treat patients with heart failure. Their goal is to decrease the amount of salt (sodium chloride) in the body by decreasing the amount that the kidney reabsorbs. This excess sodium in the kidneys that is destined for excretion via urination can cause hyponatremia (low sodium level) and can lead to kaliuresis by increasing sodium-potassium exchange.
See also
Natriuresis
Notes
External links
Merriam-Webster entry
Renal physiology
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https://en.wikipedia.org/wiki/Sense%20%28molecular%20biology%29
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In molecular biology and genetics, the sense of a nucleic acid molecule, particularly of a strand of DNA or RNA, refers to the nature of the roles of the strand and its complement in specifying a sequence of amino acids. Depending on the context, sense may have slightly different meanings. For example, the negative-sense strand of DNA is equivalent to the template strand, whereas the positive-sense strand is the non-template strand whose nucleotide sequence is equivalent to the sequence of the mRNA transcript.
DNA sense
Because of the complementary nature of base-pairing between nucleic acid polymers, a double-stranded DNA molecule will be composed of two strands with sequences that are reverse complements of each other. To help molecular biologists specifically identify each strand individually, the two strands are usually differentiated as the "sense" strand and the "antisense" strand. An individual strand of DNA is referred to as positive-sense (also positive (+) or simply sense) if its nucleotide sequence corresponds directly to the sequence of an RNA transcript which is translated or translatable into a sequence of amino acids (provided that any thymine bases in the DNA sequence are replaced with uracil bases in the RNA sequence). The other strand of the double-stranded DNA molecule is referred to as negative-sense (also negative (−) or antisense), and is reverse complementary to both the positive-sense strand and the RNA transcript. It is actually the antisense strand that is used as the template from which RNA polymerases construct the RNA transcript, but the complementary base-pairing by which nucleic acid polymerization occurs means that the sequence of the RNA transcript will look identical to the positive-sense strand, apart from the RNA transcript's use of uracil instead of thymine.
Sometimes the phrases coding strand and template strand are encountered in place of sense and antisense, respectively, and in the context of a double-stranded DNA molecule
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https://en.wikipedia.org/wiki/Ammonium%20alum
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Ammonium aluminium sulfate, also known as ammonium alum or just alum (though there are many different substances also called "alum"), is a white crystalline double sulfate usually encountered as the dodecahydrate, formula (NH4)Al(SO4)2·12H2O. It is used in small amounts in a variety of niche applications. The dodecahydrate occurs naturally as the rare mineral tschermigite.
Production and basic properties
Ammonium alum is made from aluminium hydroxide, sulfuric acid and ammonium sulfate. It forms a solid solution with potassium alum. Pyrolysis leaves alumina. Such alumina is used in the production of grinding powders and as precursors to synthetic gems.
Uses
Ammonium alum is not a major industrial chemical or a particularly useful laboratory reagent, but it is cheap and effective, which invites many niche applications. It is used in water purification, in vegetable glues, in porcelain cements, in deodorants and in tanning, dyeing and in fireproofing textiles. The pH of the solution resulting from the topical application of ammonium alum with perspiration is typically in the slightly acid range, from 3 to 5.
Ammonium alum is a common ingredient in animal repellent sprays.
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https://en.wikipedia.org/wiki/List%20of%20MeSH%20codes%20%28D12.776%29
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The following is a partial list of the "D" codes for Medical Subject Headings (MeSH), as defined by the United States National Library of Medicine (NLM).
This list continues the information at List of MeSH codes (D12.644). Codes following these are found at List of MeSH codes (D13). For other MeSH codes, see List of MeSH codes.
The source for this content is the set of 2006 MeSH Trees from the NLM.
– proteins
– albumins
– c-reactive protein
– conalbumin
– lactalbumin
– ovalbumin
– avidin
– parvalbumins
– ricin
– serum albumin
– methemalbumin
– prealbumin
– serum albumin, bovine
– serum albumin, radio-iodinated
– technetium tc 99m aggregated albumin
– algal proteins
– amphibian proteins
– xenopus proteins
– amyloid
– amyloid beta-protein
– amyloid beta-protein precursor
– serum amyloid a protein
– serum amyloid p-component
– antifreeze proteins
– antifreeze proteins, type i
– antifreeze proteins, type ii
– antifreeze proteins, type iii
– antifreeze proteins, type iv
– apoproteins
– apoenzymes
– apolipoproteins
– apolipoprotein A
– apolipoprotein A1
– apolipoprotein A2
– apolipoprotein B
– apolipoprotein C
– apolipoprotein E
– aprotinin
– archaeal proteins
– bacteriorhodopsins
– dna topoisomerases, type i, archaeal
– halorhodopsins
– periplasmic proteins
– armadillo domain proteins
– beta-catenin
– gamma catenin
– plakophilins
– avian proteins
– bacterial proteins
See List of MeSH codes (D12.776.097).
– blood proteins
See List of MeSH codes (D12.776.124).
– carrier proteins
See List of MeSH codes (D12.776.157).
– cell cycle proteins
– cdc25 phosphatase
– cellular apoptosis susceptibility protein
– cullin proteins
– cyclin-dependent kinase inhibitor proteins
– cyclin-dependent kinase inhibitor p15
– cyclin-dependent kinase inhibitor p16
– cyclin-dependent kinase inhibitor p18
– cyclin-dependent kinase inhibitor p19
– cyclin-dependent kinase inhibitor p21
– cyclin-dependent kinase inhibitor p27
– cyclin-de
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https://en.wikipedia.org/wiki/Cyclosporins
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The cyclosporins are a group of macrolides isolated from fungi and used as immunosuppresant drugs, for example after transplant surgery. They are nonribosomal peptide synthesized by cyclosporin synthetase.
Cyclosporin A (ciclosporin)
Cyclosporin B
Cyclosporin C
Cyclosporin D
Cyclosporin E
Cyclosporin F
Cyclosporin G
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https://en.wikipedia.org/wiki/Recurrent%20point
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In mathematics, a recurrent point for a function f is a point that is in its own limit set by f. Any neighborhood containing the recurrent point will also contain (a countable number of) iterates of it as well.
Definition
Let be a Hausdorff space and a function. A point is said to be recurrent (for ) if , i.e. if belongs to its -limit set. This means that for each neighborhood of there exists such that .
The set of recurrent points of is often denoted and is called the recurrent set of . Its closure is called the Birkhoff center of , and appears in the work of George David Birkhoff on dynamical systems.
Every recurrent point is a nonwandering point, hence if is a homeomorphism and is compact, then is an invariant subset of the non-wandering set of (and may be a proper subset).
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https://en.wikipedia.org/wiki/Diphtheria%20toxin
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Diphtheria toxin is an exotoxin secreted mainly by Corynebacterium diphtheriae but also by Corynebacterium ulcerans and Corynebacterium pseudotuberculosis, the pathogenic bacterium that causes diphtheria. The toxin gene is encoded by a prophage called corynephage β.
The toxin causes the disease in humans by gaining entry into the cell cytoplasm and inhibiting protein synthesis.
Structure
Diphtheria toxin is a single polypeptide chain of 535 amino acids consisting of two subunits linked by disulfide bridges, known as an A-B toxin. Binding to the cell surface of the B subunit (the less stable of the two subunits) allows the A subunit (the more stable part of the protein) to penetrate the host cell.
The crystal structure of the diphtheria toxin homodimer has been determined to 2.5 Ångstrom resolution. The structure reveals a Y-shaped molecule consisting of three domains. Fragment A contains the catalytic C domain, and fragment B consists of the T and R domains:
The amino-terminal catalytic domain, known as the C domain, has an unusual beta+alpha fold. The C domain blocks protein synthesis by transfer of ADP-ribose from NAD to a diphthamide residue of eukaryotic elongation factor 2 (eEF-2).
A central translocation domain, known as the T domain or TM domain, has a multi-helical globin-like fold with two additional helices at the amino terminus but no counterpart to the first globin helix. This domain is thought to unfold in the membrane. A pH-induced conformational change in the T domain triggers insertion into the endosomal membrane and facilitates the transfer of the C domain into the cytoplasm.
A carboxy-terminal receptor-binding domain, known as the R domain, has a beta-sandwich fold consisting of nine strands in two sheets with Greek-key topology; it is a subclass of immunoglobulin-like fold. The R domain binds to a cell surface receptor, permitting the toxin to enter the cell by receptor-mediated endocytosis.
Mechanism
Processing
The leader region is cleav
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https://en.wikipedia.org/wiki/Circular%20folds
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The circular folds (also known as valves of Kerckring, valves of Kerchkring, plicae circulares, plicae circulae, and valvulae conniventes) are large valvular flaps projecting into the lumen of the small intestine.
Structure
The entire small intestine has circular folds of mucous membrane. The majority extend transversely around the cylinder of the small intestine, for about one-half or two-thirds of its circumference. Some form complete circles. Others have a spiral direction. The latter usually extend a little more than once around the bowel, but occasionally two or three times. While the larger folds are about 1 cm in depth at their broadest part, most folds are smaller. There tends to be an alternating pattern between larger and smaller folds.
Distribution
They are not found at the commencement of the duodenum, but begin to appear about 2.5 or 5 cm beyond the pylorus.
In the lower part of the descending portion, below the point where the bile and pancreatic ducts enter the small intestine, they are very large and closely approximated.
In the horizontal and ascending portions of the duodenum and upper half of the jejunum they are large and numerous. From this point, down to the middle of the ileum, they diminish considerably in size.
In the lower part of the ileum they almost entirely disappear; hence the comparative thinness of this portion of the intestine, as compared with the duodenum and jejunum.
Difference from other gastrointestinal folds
Unlike the gastric folds in the stomach, they are permanent, and are not obliterated when the intestine is distended.
The spaces between circular folds are smaller than the haustra of the colon, and, in contrast to haustra, circular folds reach around the whole circumference of the intestine. These differences can assist in distinguishing the small intestine from the colon on an abdominal x-ray.
Function
The circular folds slow the passage of the partly digested food along the intestines, and afford an increased su
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https://en.wikipedia.org/wiki/Memory%20inhibition
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In psychology, memory inhibition is the ability not to remember irrelevant information. The scientific concept of memory inhibition should not be confused with everyday uses of the word "inhibition". Scientifically speaking, memory inhibition is a type of cognitive inhibition, which is the stopping or overriding of a mental process, in whole or in part, with or without intention.
Memory inhibition is a critical component of an effective memory system. While some memories are retained for a lifetime, most memories are forgotten. According to evolutionary psychologists, forgetting is adaptive because it facilitates selectivity of rapid, efficient recollection. For example, a person trying to remember where they parked their car would not want to remember every place they have ever parked. In order to remember something, therefore, it is essential not only to activate the relevant information, but also to inhibit irrelevant information.
There are many memory phenomena that seem to involve inhibition, although there is often debate about the distinction between interference and inhibition.
History
In the early days of psychology, the concept of inhibition was prevalent and influential (e.g., Breese, 1899; Pillsbury, 1908; Wundt, 1902). These psychologists applied the concept of inhibition (and interference) to early theories of learning and forgetting. Starting in 1894, German scientists Muller and Shumann conducted empirical studies that demonstrated how learning a second list of items interfered with memory of the first list. Based on these experiments, Muller argued that the process of attention was based on facilitation. Arguing for a different explanation, Wundt (1902) claimed that selective attention was accomplished by the active inhibition of unattended information, and that to attend to one of several simultaneous stimuli, the others had to be inhibited. American Psychologist Walter Pillsbury combined Muller and Wundt's arguments, claiming that attention bo
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https://en.wikipedia.org/wiki/Cyclic%20nucleotide%20phosphodiesterase
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3′,5′-cyclic-nucleotide phosphodiesterases (EC 3.1.4.17) are a family of phosphodiesterases. Generally, these enzymes hydrolyze a nucleoside 3′,5′-cyclic phosphate to a nucleoside 5′-phosphate:
nucleoside 3′,5′-cyclic phosphate + H2O = nucleoside 5′-phosphate
They thus control the cellular levels of the cyclic second messengers and the rates of their degradation.
Some examples of nucleoside 3′,5′-cyclic phosphate include:
3′,5′-cyclic AMP
3′,5′-cyclic dAMP
3′,5′-cyclic IMP
3′,5′-cyclic GMP
3′,5′-cyclic CMP
There are 11 distinct phosphodiesterase families (PDE1–PDE11) with a variety in isoforms and splicing having unique three-dimensional structure, kinetic properties, modes of regulation, intracellular localization, cellular expression, and inhibitor sensitivities.
Nomenclature
The systematic name for this enzyme is 3′,5′-cyclic-nucleotide 5'-nucleotidohydrolase. Other names in use include:
PDE,
cyclic 3′,5′-mononucleotide phosphodiesterase,
cyclic 3',5'-nucleotide phosphodiesterase,
cyclic 3′,5′-phosphodiesterase,
3′,5′-nucleotide phosphodiesterase,
3':5'-cyclic nucleotide 5′-nucleotidohydrolase,
3′,5′-cyclonucleotide phosphodiesterase,
3′,5′-cyclic nucleoside monophosphate phosphodiesterase,
3′:5′-monophosphate phosphodiesterase (cyclic CMP),
cytidine 3′:5′-monophosphate phosphodiesterase (cyclic CMP),
cyclic 3′,5-nucleotide monophosphate phosphodiesterase,
nucleoside 3′,5′-cyclic phosphate diesterase, and
nucleoside-3′,5-monophosphate phosphodiesterase.
Function
Phototransduction
Retinal 3′,5′-cGMP phosphodiesterase (PDE) is located in photoreceptor outer segments and is an important enzyme in phototransduction.
3′,5′-cyclic-nucleotide phosphodiesterases in rod cells are oligomeric, made up of two heavy catalytic subunits, α (90 kDa) and β (85 kDa,) and two lighter inhibitory γ subunits (11 kDa each).
PDE in rod cells are activated by transducin. Transducin is a G protein which upon GDP/GTP exchange in the transducin α subun
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https://en.wikipedia.org/wiki/DNA%20ligase%20%28NAD%2B%29
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DNA ligase (NAD+) (, polydeoxyribonucleotide synthase (NAD+), polynucleotide ligase (NAD+), DNA repair enzyme, DNA joinase, polynucleotide synthetase (nicotinamide adenine dinucleotide), deoxyribonucleic-joining enzyme, deoxyribonucleic ligase, deoxyribonucleic repair enzyme, deoxyribonucleic joinase, DNA ligase, deoxyribonucleate ligase, polynucleotide ligase, deoxyribonucleic acid ligase, polynucleotide synthetase, deoxyribonucleic acid joinase, DNA-joining enzyme, polynucleotide ligase (nicotinamide adenine dinucleotide)) is an enzyme with systematic name poly(deoxyribonucleotide):poly(deoxyribonucleotide) ligase (AMP-forming, NMN-forming). This enzyme catalyses the following chemical reaction
NAD+ + (deoxyribonucleotide)n + (deoxyribonucleotide)m AMP + beta-nicotinamide D-ribonucleotide + (deoxyribonucleotide)n+m
Catalyses the formation of a phosphodiester at the site of a single-strand break in duplex DNA.
See also
DNA ligase
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https://en.wikipedia.org/wiki/Blue%20pages
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Blue pages are a telephone directory listing of American and Canadian state agencies, government agencies, federal government and other official entities, along with specific offices, departments, or bureaus located wherein.
Canada
Canadian yellow-page listings currently indicate "Government Of Canada-See Government Listings In The Blue Pages"; in markets where the local telephone directory is a single volume, the blue pages and community information normally appear after the alphabetical white-page listings but before the yellow pages advertising. The blue page listings include both provincial and federal entities.
United States
In the United States, the blue pages included state, federal, and local offices, including service districts such as school districts, port authorities, public utility providers, parks districts, fire districts, and the like. The blue pages also provided information about government services, in addition to officials' names, addresses, telephone numbers, and other contact information. The color blue is likely derived from so-called government blue books, official publications printed by a government (such as that of a state) describing its organization, and providing a list of contact information. (The blue pages published in a printed telephone directory is usually quite abridged, compared to official blue books).
Other
The name "blue pages" has been used for various specialised directories by private-sector entities such as the internal IBM Staff directory.
External links
"USA Blue Pages" - officialusa.com, an unofficial blue pages directory for US federal and state agencies
Telephone numbers
Directories
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https://en.wikipedia.org/wiki/Peopleware%3A%20Productive%20Projects%20and%20Teams
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Peopleware: Productive Projects and Teams is a 1987 book on the social side of software development, specifically managing project teams. It was written by software consultants Tom DeMarco and Tim Lister, from their experience in the world of software development. This book was revised in 1999 and 2016.
Overview
Peopleware is a popular book about software organization management. The first chapter of the book claims, "The major problems of our work are not so much technological as sociological in nature". The book approaches sociological or 'political' problems such as group chemistry and team jelling, "flow time" and quiet in the work environment, and the high cost of turnover. Other topics include the conflicts between individual work perspective and corporate ideology, corporate entropy, "teamicide" and workspace theory.
The authors presented most subjects as principles backed up by some concrete story or other information. As an example, the chapter "Spaghetti Dinner" presents a fictional example of a manager inviting a new team over for dinner, then having them buy and prepare the meal as a group, in order to produce a first team success. Other chapters use real-life stories or cite various studies to illustrate the principles being presented.
Editions
1st Edition: 1987
2nd Edition: 1999
The second edition kept the original content with only a few changes or corrections. The bulk of the new content was eight chapters in a new section at the end. The new section's chapters revisited some of the concepts of the original chapters with changes and added new ones.
The eBook PDF version published by DorsetHouse was not searchable as each page appeared to be an image. The Kindle version is searchable.
3rd Edition: 2016
The new content of the third edition is spread out through the book. There are six new chapters, but the original content has also been updated.
See also
Peopleware as a more general concept.
The Mythical Man-Month
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https://en.wikipedia.org/wiki/Flags%20of%20South%20America
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This is a gallery of flags of South American countries and affiliated international organizations.
International
Flags of South American sovereign states
Flags of South American dependencies and other territories
Flags of South American cities
Flags of cities with over 1 million inhabitants.
Historical flags
See also
Flags of North America
Flag of Gran Colombia
Flags depicting the Southern Cross
List of countries
Sun of May
Wiphala
Lists of flags of South American countries
List of Argentine flags
List of Brazilian flags
List of Chilean flags
List of Colombian flags
List of Ecuadorian flags
List of flags of Peru
List of Uruguayan flags
List of flags of Venezuela
South America
South America
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https://en.wikipedia.org/wiki/Piriformis%20nerve
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The piriformis nerve, also known as the nerve to piriformis, is the peripheral nerve that provides motor innervation to the piriformis muscle.
Structure
Origin
The nerve to piriformis is a branch of the sacral plexus. It (typically) arises from the posterior divisions/branches of anterior rami of S1 and S2.
Course
It enters the anterior surface of the piriformis muscle.
Variation
Origin
It may sometimes arise from the anterior ramus of S2 only.
Number
It may be doubled. An additional branch may arise from the superior gluteal nerve.
Distribution
The piriformis nerve innervates the piriformis muscle.
See also
Piriformis
Sacral plexus
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https://en.wikipedia.org/wiki/Nerve%20to%20obturator%20internus
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The nerve to obturator internus (also known as the obturator internus nerve) is a mixed (sensory and motor) nerve providing motor innervation to the obturator internus muscle and gemellus superior muscle, and sensory innervation to the hip joint. It is a branch of the sacral plexus. It is one of the group of deep gluteal nerves.
It exits the pelvis through the greater sciatic foramen to innervate the gemellus superior muscle, then re-enters the pelvis to innervate the obturator internus muscle.
Structure
Origin
The nerve to obturator internus is a branch of the lumbosacral plexus. It arises from the anterior divisions of (the anterior rami of) L5-S2.
Course and relations
It emerges inferior to the piriformis muscle and exits the pelvis through the greater sciatic foramen. It travels round the base of the ischial spine lateral to the internal pudendal artery and nerve, and - while doing so - issues a branch to the gemellus superior, which enters the upper part of the posterior surface of the muscle. It then re-enters the pelvis through the lesser sciatic foramen to innervate the obturator internus muscle, piercing the pelvic surface of this muscle.
See also
Obturator nerve
Nerve to quadratus femoris
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https://en.wikipedia.org/wiki/Nerve%20to%20quadratus%20femoris
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The nerve to quadratus femoris is a nerve of the sacral plexus that provides motor innervation to the quadratus femoris muscle and gemellus inferior muscle, and an articular branch to the hip joint. The nerve leaves the pelvis through the greater sciatic foramen.
Structure
Origin
The nerve to quadratus femoris is a branch of the sacral plexus. It arises from the anterior divisions of the spinal nerves L4-S1.
Course
It exits the pelvis through the greater sciatic foramen inferior to the piriformis muscle.
It passes inferior-ward upon the ischium deep to the sciatic nerve, the superior and inferior gemellus muscles, and the tendon of the obturator internus. It traverses the posterior aspect of the hip joint, here issuing an articular (sensory) branch to the joint. It proceeds inferior-ward deep to the superior and inferior gemelli muscles and the obturator internus muscle.
It enters the anterior surfaces of quadratus femoris muscle and gemellus inferior muscle.
Variation
Rarely, the nerve to quadratus femoris may also innervate the gemellus superior muscle, or the upper part of adductor magnus muscle.
Function
The nerve to quadratus femoris provides motor innervation to quadratus femoris muscle and inferior gemellus muscle. It also provides sensory innervation to the hip joint.
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https://en.wikipedia.org/wiki/Dorsal%20artery%20of%20the%20penis
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The dorsal artery of the penis is an artery on the top surface of the penis. It is a branch of the internal pudendal artery. It runs forward on the dorsum of the penis to the glans, where it divides into two branches to the glans penis and the foreskin (prepuce).
The dorsal artery of the penis supplies the integument and fibrous sheath of the corpus cavernosum penis, the glans penis, the foreskin, and the skin of the distal shaft. It also branches with circumflex arteries that supply the corpus spongiosum. Its role in erectile function is unknown.
The dorsal artery of the penis may be damaged in traumatic amputation of the penis and repairing the dorsal artery surgically prevents skin loss, but it is not essential for sexual and urinary function. Its hemodynamics and blood pressure can be assessed to test for sexual impairment.
Structure
The dorsal artery of the penis is a branch of the internal pudendal artery. It ascends between the crus penis and the pubic symphysis of the pelvis. As it pierces the perineal membrane, it passes between the two layers of the suspensory ligament of the penis. It runs forward on the dorsum of the penis to the glans. At the glans, it divides into two branches to the glans penis and the foreskin (prepuce). On the penis, it lies between the dorsal nerve and deep dorsal vein.
The dorsal artery give perforators to the corpus cavernosum penis. It sends branches through the fibrous sheath of the corpus cavernosum penis to anastomose with the deep artery of the penis. It anastomoses with the artery of bulb of penis.
Function
The dorsal artery of the penis supplies the fibrous sheath of the corpus cavernosum penis. It gives branches to the glans penis, and the foreskin (prepuce). Through retrograde flow they help supply the skin of the distal shaft. It also gives branches to the circumflex arteries that supply the corpus spongiosum.
The dorsal artery of the penis gives perforators to the corpus cavernosum penis. Despite this, their
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https://en.wikipedia.org/wiki/Dorsal%20nerve%20of%20the%20penis
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The dorsal nerve of the penis is the deepest of three divisions of the pudendal nerve; it accompanies the internal pudendal artery along the ramus of the ischium; it then runs forward along the margin of the inferior ramus of the pubis, between the superior and inferior layers of the fascia of the urogenital diaphragm.
Piercing the inferior layer it gives a branch to the corpus cavernosum penis, and passes forward, in company with the dorsal artery of the penis, between the layers of the suspensory ligament, on to the dorsum of the penis, and ends on the glans penis.
It innervates the skin of the penis. In humans, it has 8290 ± 2553 axons, in 25–45 loosely packed nerve bundles, half of which are myelinated. The researches were conducted on volunteers that donated tissues after death, therefore some of the nerve endings couldn’t have been counted due to the natural degeneration of tissues found in old people.
Gallery
See also
Cavernous nerves of penis
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https://en.wikipedia.org/wiki/Expansive%20homeomorphism
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In mathematics, the notion of expansivity formalizes the notion of points moving away from one another under the action of an iterated function. The idea of expansivity is fairly rigid, as the definition of positive expansivity, below, as well as the Schwarz–Ahlfors–Pick theorem demonstrate.
Definition
If is a metric space, a homeomorphism is said to be expansive if there is a constant
called the expansivity constant, such that for every pair of points in there is an integer such that
Note that in this definition, can be positive or negative, and so may be expansive in the forward or backward directions.
The space is often assumed to be compact, since under that assumption expansivity is a topological property; i.e. if is any other metric generating the same topology as , and if is expansive in , then is expansive in (possibly with a different expansivity constant).
If
is a continuous map, we say that is positively expansive (or forward expansive) if there is a
such that, for any in , there is an such that .
Theorem of uniform expansivity
Given f an expansive homeomorphism of a compact metric space, the theorem of uniform expansivity states that for every and there is an such that for each pair of points of such that , there is an with such that
where is the expansivity constant of (proof).
Discussion
Positive expansivity is much stronger than expansivity. In fact, one can prove that if is compact and is a positively
expansive homeomorphism, then is finite (proof).
External links
Expansive dynamical systems on scholarpedia
Dynamical systems
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https://en.wikipedia.org/wiki/Ishango%20bone
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The Ishango bone, discovered at the "Fisherman Settlement" of Ishango in the Democratic Republic of Congo, is a bone tool and possible mathematical device that dates to the Upper Paleolithic era. The curved bone is dark brown in color, about 10 centimeters in length, and features a sharp piece of quartz affixed to one end, perhaps for engraving. Because the bone has been narrowed, scraped, polished, and engraved to a certain extent, it is no longer possible to determine what animal the bone belonged to, although it is assumed to belong to a mammal.
The ordered engravings have led many to speculate the meaning behind these marks, including interpretations like mathematical significance or astrological relevance. It is thought by some to be a tally stick, as it features a series of what has been interpreted as tally marks carved in three columns running the length of the tool, though it has also been suggested that the scratches might have been to create a better grip on the handle or for some other non-mathematical reason. Others argue that the marks on the object are non-random and that it was likely a kind of counting tool and used to perform simple mathematical procedures. Other speculations include the engravings on the bone serving as a lunar calendar. Dating to 20,000 years before present, it is regarded as the oldest mathematical tool to humankind, with the possible exception of the approximately 40,000-year-old Lebombo bone from southern Africa.
History
Archaeological discovery
The Ishango bone was found in 1950 by Belgian Jean de Heinzelin de Braucourt while exploring what was then the Belgian Congo. It was discovered in the area of Ishango near the Semliki River. Lake Edward empties into the Semliki which forms part of the headwaters of the Nile River (now on the border between modern-day Uganda and D.R. Congo). Some archaeologists believe the prior inhabitants of Ishango were a "pre-sapiens species". However, the most recent inhabitants, who gave the a
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https://en.wikipedia.org/wiki/Delegated%20administration
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In computing, delegated administration or delegation of control describes the decentralization of role-based-access-control systems. Many enterprises use a centralized model of access control. For large organizations, this model scales poorly and IT teams become burdened with menial role-change requests. These requests — often used when hire, fire, and role-change events occur in an organization — can incur high latency times or suffer from weak security practices.
Such delegation involves assigning a person or group specific administrative permissions for an Organizational Unit. In information management, this is used to create teams that can perform specific (limited) tasks for changing information within a user directory or database. The goal of delegation is to create groups with minimum permissions that grant the ability to carry out authorized tasks. Granting extraneous/superfluous permissions would create abilities beyond the authorized scope of work.
One best practice for enterprise role management entails the use of LDAP groups. Delegated administration refers to a decentralized model of role or group management. In this model, the application or process owner creates, manages and delegates the management of roles. A centralized IT team simply operates the service of directory, metadirectory, web interface for administration, and related components.
Allowing the application or business process owner to create, manage and delegate groups supports a much more scalable approach to the administration of access rights.
In a metadirectory environment, these roles or groups could also be "pushed" or synchronized with other platforms. For example, groups can be synchronized with native operating systems such as Microsoft Windows for use on an access control list that protects a folder or file. With the metadirectory distributing groups, the central directory is the central repository of groups.
Some enterprise applications (e.g., PeopleSoft) support
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https://en.wikipedia.org/wiki/EigenTrust
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EigenTrust algorithm is a reputation management algorithm for peer-to-peer networks, developed by Sep Kamvar, Mario Schlosser, and Hector Garcia-Molina. The algorithm provides each peer in the network a unique global trust value based on the peer's history of uploads and thus aims to reduce the number of inauthentic files in a P2P network. It has been cited by approximately 3853 other articles according to Google Scholar.
Overview
Peer-to-peer systems available today (like Gnutella) are open, often anonymous and lack accountability. Hence a user with malicious intent can introduce into the peer-to-peer network resources that may be inauthentic, corrupted or malicious (Malware). This reflects poorly on the credibility of current peer-to-peer systems. A research team from Stanford provides a reputation management system, where each peer in the system has a unique global trust value based on the peer's history of uploads. Any peer requesting resources will be able to access the trust value of a peer and avoid downloading files from untrusted peers.
Algorithm
The Eigentrust algorithm is based on the notion of transitive trust: If a peer i trusts any peer j, it would also trust the peers trusted by j. Each peer i calculates the local trust value sij for all peers that have provided it with authentic or fake downloads based on the satisfactory or unsatisfactory transactions that it has had.
where sat (i, j) refers to the number of satisfactory responses that peer i has received from peer j,
and unsat(i, j) refers to the number of unsatisfactory responses that peer i has received from peer j.
The local value is normalized, to prevent malicious peers from assigning arbitrarily high local trust values to colluding malicious peers and arbitrarily low local trust values to good peers. The normalized local trust value cij is then
The local trust values are aggregated at a central location or in a distributed manner to create a trust vector for the whole network. Based o
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https://en.wikipedia.org/wiki/Species%20distribution
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Species distribution, or species dispersion, is the manner in which a biological taxon is spatially arranged. The geographic limits of a particular taxon's distribution is its range, often represented as shaded areas on a map. Patterns of distribution change depending on the scale at which they are viewed, from the arrangement of individuals within a small family unit, to patterns within a population, or the distribution of the entire species as a whole (range). Species distribution is not to be confused with dispersal, which is the movement of individuals away from their region of origin or from a population center of high density.
Range
In biology, the range of a species is the geographical area within which that species can be found. Within that range, distribution is the general structure of the species population, while dispersion is the variation in its population density.
Range is often described with the following qualities:
Sometimes a distinction is made between a species' natural, endemic, indigenous, or native range, where it has historically originated and lived, and the range where a species has more recently established itself. Many terms are used to describe the new range, such as non-native, naturalized, introduced, transplanted, invasive, or colonized range. Introduced typically means that a species has been transported by humans (intentionally or accidentally) across a major geographical barrier.
For species found in different regions at different times of year, especially seasons, terms such as summer range and winter range are often employed.
For species for which only part of their range is used for breeding activity, the terms breeding range and non-breeding range are used.
For mobile animals, the term natural range is often used, as opposed to areas where it occurs as a vagrant.
Geographic or temporal qualifiers are often added, such as in British range or pre-1950 range. The typical geographic ranges could be the latitudinal range an
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https://en.wikipedia.org/wiki/Guanylin
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Guanylin is a 15 amino acid peptide that is secreted by goblet cells in the colon. Guanylin acts as an agonist of the guanylyl cyclase receptor GC-C and regulates electrolyte and water transport in intestinal and renal epithelia. Upon receptor binding, guanylin increases the intracellular concentration of cGMP, induces chloride secretion and decreases intestinal fluid absorption, ultimately causing diarrhoea. The peptide stimulates the enzyme through the same receptor binding
region as the heat-stable enterotoxins.
Researches have found that a loss in guanylin expression can lead to colorectal cancer due to guanylyl cyclase C's function as an intestinal tumor suppressor. When guanylin expression was measured on over 250 colon cancer patients, more than 85% of patients had a loss of guanylin expression in cancerous tissue samples by 100-1000 times when compared to the same patients's nearby healthy colon tissue. Another study done on genetically engineered mice found that mice on a high calorie diet had reduced guanylin expression in the colon. This loss of expression then resulted in guanylyl cyclase C inhibition and the formation of tumors, therefore linking diet-induced obesity with colorectal cancer.
Human proteins containing this domain
GUCA2A; GUCA2B;
Structure
This peptide has two topogies, both isoforms are shown below:
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https://en.wikipedia.org/wiki/SoapUI
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SoapUI is an open-source web service testing application for Simple Object Access Protocol (SOAP) and representational state transfers (REST). Its functionality covers web service inspection, invoking, development, simulation and mocking, functional testing, load and compliance testing. A commercial version, ReadyAPI (formerly SoapUI Pro), which mainly focuses on features designed to enhance productivity, was also developed by Eviware Software AB. In 2011, SmartBear Software acquired Eviware.
SoapUI was initially released to SourceForge in September 2005. It is free software, licensed under the terms of the European Union Public License. Since the initial release, SoapUI has been downloaded more than 2,000,000 times. It is built entirely on the Java platform, and uses Swing for the user interface. This means that SoapUI is cross-platform. Today, SoapUI also supports IDEA, Eclipse, and NetBeans.
SoapUI can test SOAP and REST web services, JMS, AMF, as well as make any HTTP(S) and JDBC calls.
Features
SoapUI
Core features include web services:
inspection
invoking
development
simulation and mocking
functional, compliance and security testing
ReadyAPI
ReadyAPI is the commercial enterprise version. ReadyAPI adds a number of productivity enhancements to the SoapUI core, which are designed to ease many recurring tasks when working with SoapUI.
Awards
SoapUI has been given a number of awards. These include:
Jolt Awards 2014: The Best Testing Tools
ATI Automation Honors, 2009
InfoWorld Best of Open Source Software Award, 2008
SOAWorld Readers' Choice Award, 2007
See also
Apache JMeter
Automated testing
itko
List of unit testing frameworks
LoadUI
Software testing
System testing
Test case
Test-driven development
TestComplete
xUnit – a family of unit testing frameworks
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https://en.wikipedia.org/wiki/Transrepression
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In the field of molecular biology, transrepression is a process whereby one protein represses (i.e., inhibits) the activity of a second protein through a protein-protein interaction. Since this repression occurs between two different protein molecules (intermolecular), it is referred to as a trans-acting process.
The protein that is repressed is usually a transcription factor whose function is to up-regulate (i.e., increase) the rate of gene transcription. Hence the net result of transrepression is down regulation of gene transcription.
An example of transrepression is the ability of the glucocorticoid receptor to inhibit the transcriptional promoting activity of the AP-1 and NF-κB transcription factors. In addition to transactivation, transrepression is an important pathway for the anti-inflammatory effects of glucocorticoids. Other nuclear receptors such as LXR and PPAR have been demonstrated to also have the ability to transrepress the activity of other proteins.
See also
Selective glucocorticoid receptor agonist
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https://en.wikipedia.org/wiki/F-plasmid
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The F-plasmid (first named F by one of its discoverers Esther Lederberg；also called the sex factor in E. coli， the F sex factor, or the fertility factor) allows genes to be transferred from one bacterium carrying the factor to another bacterium lacking the factor by conjugation. The F factor was the first plasmid to be discovered. Unlike other plasmids, F factor is constitutive for transfer proteins due to a mutation in the gene finO. The F plasmid belongs to F-like plasmids, a class of conjugative plasmids that control sexual functions of bacteria with a fertility inhibition (Fin) system.
Discovery
Esther M. Lederberg and Luigi L. Cavalli-Sforza discovered "F," subsequently publishing with Joshua Lederberg. Once her results were announced, two other labs joined the studies. "This was not a simultaneous independent discovery of F (I names as Fertility Factor until it was understood.) We wrote to Hayes, Jacob, & Wollman who then proceeded with their studies." The discovery of "F" has sometimes been confused with William Hayes' discovery of "sex factor", though he never claimed priority. Indeed, "he [Hayes] thought F was really lambda, and when we convinced him [that it was not], he then began his work."
Structure
The most common functional segments constituting F factors are:
OriT (Origin of Transfer): The sequence which marks the starting point of conjugative transfer.
OriV (Origin of Vegetative Replication): The sequence starting with which the plasmid-DNA will be replicated in the recipient cell.
tra-region (transfer genes): Genes coding the F-Pilus and DNA transfer process.
IS (Insertion Elements) composed of one copy of IS2, two copies of IS3, and one copy of IS1000: so-called "selfish genes" (sequence fragments which can integrate copies of themselves at different locations).
Some F plasmid genes and their Function:
traA: F-pilin, Major subunit of the F-pilus.
traN: recognizes cell-surface receptors
Relation to the genome
The episome that harbors
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https://en.wikipedia.org/wiki/Flags%20of%20North%20America
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This is a gallery of flags of North American countries, territories and their affiliated international organizations.
International organizations
Intercontinental organizations
Intracontinental organizations
Flags of North American sovereign states
Flags of North American dependencies and other territories
Flags of North American cities
Flags of cities with over 1 million inhabitants.
Historical flags
See also
List of sovereign states and dependent territories in North America
Subregions of North America
Lists of flags of North American countries
List of Antiguan and Barbudan flags
List of Bahamian flags
List of Barbadian flags
List of Belizean flags
List of Canadian flags
List of Costa Rican flags
List of Cuban flags
List of Dominican flags
List of Dominican Republic flags
List of Guatemalan flags
List of Haitian flags
List of Jamaican flags
List of Mexican flags
List of Nicaraguan flags
List of Trinidadian and Tobagonian flags
List of flags of the United States
North America
North America
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https://en.wikipedia.org/wiki/Rosa%20%C3%97%20centifolia
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Rosa × centifolia (lit. hundred leaved rose; syn. R. gallica var. centifolia (L.) Regel), the Provence rose, cabbage rose or Rose de Mai, is a hybrid rose developed by Dutch breeders in the period between the 17th century and the 19th century, possibly earlier.
History
Its parentage includes Rosa × damascena, but it may be a complex hybrid; its exact hereditary history is not well documented or fully investigated, but it now appears that this is not the "hundred-leaved" (centifolia) rose mentioned by Theophrastus and Pliny: "no unmistakable reference can be traced earlier than about 1580".
The original plant was sterile, but a sport with single flowers appeared in 1769, from which various cultivars known as centifolia roses were developed, many of which are further hybrids. Other cultivars have appeared as further sports from these roses. Rosa × centifolia 'Muscosa' is a sport with a thick covering of resinous hairs on the flower buds, from which most (but not all) "moss roses" are derived. Dwarf or miniature sports have been known for almost as long as the larger forms, including a miniature moss rose 'Moss de Meaux'.
In 1783 the French artist Élisabeth Vigée Le Brun painted a famous portrait of Marie Antoinette holding a pink centifolia rose.
Growth
Individual plants are shrubby in appearance, growing to 1.5–2 m tall, with long drooping canes and greyish green pinnate leaves with 5-7 leaflets. The flowers are round and globular, with numerous thin overlapping petals that are highly scented; they are usually pink, less often white to dark red-purple.
Cultivation and uses
R. × centifolia is particular to the French city of Grasse, known as the perfume capital of the world. It is widely cultivated for its singular fragrance — clear and sweet, with light notes of honey. The flowers are commercially harvested for the production of rose oil, which is commonly used in perfumery.
Centifolia cultivars
Cultivars of Rosa × centifolia that are still grown include:
'Bu
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https://en.wikipedia.org/wiki/Toobin%27
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Toobin is an Atari Games and Midway Games arcade video game released in 1988. It is based on the recreational activity tubing. Toobin was ported to the Amiga, Commodore 64, Atari ST, Amstrad CPC, Nintendo Entertainment System, MS-DOS, Game Boy Color, ZX Spectrum, and MSX. Players assume control of tubers Bif or Jet, guiding them along vertically scrolling rivers on an inner tube.
Gameplay
The player competes in a river race against the computer or another player. The player's score increases by swishing the gates, hitting other characters with cans, collecting hidden letters to spell Toobin, and collecting treasures. Players try to avoid obstacles while pushing each other into them.
Power-ups allow players to carry multiple cans and combinations of gates increase a score multiplier. The game has three different classes, each with five rivers, for a total of 15.
Legacy
The game is included as part of Midway Arcade Treasures and Arcade Party Pak, where it was given a remixed soundtrack. It was also included in the 2012 compilation Midway Arcade Origins. The game is one of the 23 arcade games that are included with the Midway Arcade Level Pack for Lego Dimensions, unlocked by using the hidden Arcade Dock in the level "Follow The Lego Brick Road". It is also an included title on the Arcade1Up Midway Legacy Edition cabinet.
See also
Swimmer
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https://en.wikipedia.org/wiki/Kronecker%20limit%20formula
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In mathematics, the classical Kronecker limit formula describes the constant term at s = 1 of a real analytic Eisenstein series (or Epstein zeta function) in terms of the Dedekind eta function. There are many generalizations of it to more complicated Eisenstein series. It is named for Leopold Kronecker.
First Kronecker limit formula
The (first) Kronecker limit formula states that
where
E(τ,s) is the real analytic Eisenstein series, given by
for Re(s) > 1, and by analytic continuation for other values of the complex number s.
γ is Euler–Mascheroni constant
τ = x + iy with y > 0.
, with q = e2π i τ is the Dedekind eta function.
So the Eisenstein series has a pole at s = 1 of residue π, and the (first) Kronecker limit formula gives the constant term of the Laurent series at this pole.
This formula has an interpretation in terms of the spectral geometry of the elliptic curve associated to the lattice : it says that the zeta-regularized determinant of the Laplace operator associated to the flat metric on is given by . This formula has been used in string theory for the one-loop computation in Polyakov's perturbative approach.
Second Kronecker limit formula
The second Kronecker limit formula states that
where
u and v are real and not both integers.
q = e2π i τ and qa = e2π i aτ
p = e2π i z and pa = e2π i az
for Re(s) > 1, and is defined by analytic continuation for other values of the complex number s.
See also
Herglotz–Zagier function
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https://en.wikipedia.org/wiki/Flag%20of%20Martinique
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The flag of Martinique consists of a red triangle at the hoist, with two horizontal bands, the upper green and the lower black. It was adopted on 2 February 2023. The flag of France, its parent country, is also flown with official standing due to Martinique's status as a French overseas department/region. The assembly of Martinique flies a flag with the collectivity's logo on it to represent the government.
In 2018, the assembly held a competition to create a flag and anthem for the island, but 2½ years following the presentation of the winners, the flag and anthem were annulled by the local administrative tribunal, as the method of their selection were not deemed within the responsibilities of the council. Then in 2022, the island began a new public vote on an official flag and anthem. The winners were announced on 16 January 2023, but the selected flag design would be withdrawn from consideration at the request of the designer following accusations of plagiarism. Instead, it was decided that the runner-up design, an established flag used by nationalists, would be considered for adoption on 2 February 2023. It was adopted by the assembly with 44 votes in favour and one abstention.
2022 flag consultation
Prior to 2023, Martinique did not have its own flag. In 2018, the local council held a competition to create a flag and anthem for the island, but 2½ years following the presentation of the winners, the flag and anthem were annulled by the local administrative tribunal, as the method of their selection was not deemed within the responsibilities of the council. In 2022, the island began a public vote on an official flag and anthem. However, turnout for the first phase, which narrowed the choices down to two options, was very low, with only 19,084 voting for a flag and 9,294 for the anthem out of an eligible population of around 300,000. The winners, announced 16 January 2023, were the hummingbird design for the flag and "Ansanm" for the anthem, representing 72.84
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https://en.wikipedia.org/wiki/Symmetric%20hypergraph%20theorem
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The Symmetric hypergraph theorem is a theorem in combinatorics that puts an upper bound on the chromatic number of a graph (or hypergraph in general). The original reference for this paper is unknown at the moment, and has been called folklore.
Statement
A group acting on a set is called transitive if given any two elements and in , there exists an element of such that . A graph (or hypergraph) is called symmetric if its automorphism group is transitive.
Theorem. Let be a symmetric hypergraph. Let , and let denote the chromatic number of , and let denote the independence number of . Then
Applications
This theorem has applications to Ramsey theory, specifically graph Ramsey theory. Using this theorem, a relationship between the graph Ramsey numbers and the extremal numbers can be shown (see Graham-Rothschild-Spencer for the details).
See also
Ramsey theory
Notes
Graph coloring
Theorems in graph theory
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https://en.wikipedia.org/wiki/Control%20register
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A control register is a processor register that changes or controls the general behavior of a CPU or other digital device. Common tasks performed by control registers include interrupt control, switching the addressing mode, paging control, and coprocessor control.
History
When IBM developed a paging version of the System/360, they added 16 control registers to the design for what became the 360/67. IBM did not provide control registers on other S/360 models, but made them a standard part of System/370, although with different register and bit assignments. As IBM added new features to the architecture, e.g., DAS, S/370-XA, S/370-ESA, ESA/390, they added additional fields to the control registers. With z/Architecture, IBM doubled the control register size to 64 bits.
Control registers in IBM 360/67
On the 360/67, CR0 and CR2 are used by address translation, CR 4-6 contain miscellaneous flags including interrupt masks and Extended Control Mode, and CR 8-14 contain the switch settings on the 2167 Configuration Unit.
M67 CR0
Control Register 0 contains the address of the segment table for dynamic address translation.
M67 CR2
Control register 2 is the Relocation exception address register.
M67 CR4
CR4 is the extended mask register for channels 0-31.
Each bit is the 1/0 channel mask for the corresponding channel.
M67 CR5
CR5 is reserved for the extended mask register for channels 32–63.
Each bit is the 1/0 channel mask for the corresponding channel.
M67 CR6
CR6 contains two mode flags plus extensions to the PSW mask bits.
M67 CR8
Control Register 8 contains the assignments of Processor Storage units 1–4 to central processing units (CPUs) and channel controllers (CCs).
M67 CR9
Control Register 9 contains the assignments of Processor Storage units 5–8 to central processing units (CPUs) and channel controllers (CCs).
M67 CR10
Control Register 10 contains the Processor storage address assignment codes.
M67 CR11
Control Register 11 contains channel
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https://en.wikipedia.org/wiki/GAUSS%20%28software%29
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GAUSS is a matrix programming language for mathematics and statistics, developed and marketed by Aptech Systems. Its primary purpose is the solution of numerical problems in statistics, econometrics, time-series, optimization and 2D- and 3D-visualization. It was first published in 1984 for MS-DOS and is available for Linux, macOS and Windows.
Examples
GAUSS has several Application Modules as well as functions in its Run-Time Library (i.e., functions that come with GAUSS without extra cost)
Qprog – Quadratic programming
SqpSolvemt – Sequential quadratic programming
QNewton - Quasi-Newton unconstrained optimization
EQsolve - Nonlinear equations solver
GAUSS Applications
A range of toolboxes are available for GAUSS at additional cost.
See also
List of numerical-analysis software
Comparison of numerical-analysis software
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https://en.wikipedia.org/wiki/Glaze3D
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Glaze3D was a family of graphics cards announced by BitBoys Oy on August 2, 1999, that would have produced substantially better performance than other consumer products available at the time. The family, which would have come in the Glaze3D 1200, Glaze3D 2400 and Glaze3D 4800 models, was supposed to offer full support for DirectX 7, OpenGL 1.2, AGP 4×, 4× anisotropic filtering, full-screen anti-aliasing and a host of other technologies not commonly seen at the time. The 1.5 million gate GPU would have been fabricated by Infineon on a 0.2 μm eDRAM process, later to be reduced to 0.17 μm with a minimum of 9 MB of embedded DRAM and 128 to 512 MB of external SDRAM. The maximum supported video resolution was 2048×1536 pixels.
Development history
The Glaze3D family of cards were developed in several generations, beginning with the original Glaze3D "400" with multi-channel RDRAM instead of internal eDRAM. This was offered only as IP but with no takers. Bitboys revised the design and decided to have it manufactured themselves, in cooperation with Infineon Technologies, the chip fabrication arm of Siemens. They came up with a new Glaze3D pitched for release in Q1, 2000. The card promised extremely high performance compared to contemporary consumer GPUs. As bug-hunting, validation and manufacturing problems delayed the launch, new features became necessary and a DX7 variant with built-in hardware Transform & Lighting was announced, but never appeared.
The GPU was later redesigned under a new codename, Axe, to take advantage of DirectX 8 and compete with a developing competition. The new version sported such features as an additional 3 MB of eDRAM, proprietary Matrix Antialiasing and a vastly improved fillrate, as well as offering a programmable vertex shader and widened internal memory bus. The new card was to have been released as Avalanche3D by the end of 2001.
The third development, codenamed Hammer, started development as Axe lost viability toward the end of 2001. Thi
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https://en.wikipedia.org/wiki/Mauke%20starling
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The Mauke starling or mysterious starling (Aplonis mavornata) is an extinct species of starling found on the island of Mauke, Cook Islands. The binomen is the result of Buller's misreading of the name inornata on the specimen label. As he seems to have genuinely believed this spelling to be correct, the binomial, although it has no meaning, is valid.
Description
Its overall length is . Bill from gape , from anterior margin of nostril, 1.24 cm. Tarsus 2.74 cm, tail 6.4 cm, wing 10.5 cm, wingspan 32 cm. Wing and tarsus measurement are somewhat less than in the living bird due to shrinkage of the specimen. The other measurements are either from the freshly killed bird or are unlikely to have changed. Dull dusky black overall, with lighter brown feather edges which are prominent on the body feathers and less conspicuous on the remiges and tail. Iris yellow. Feet dusky brownish; bill the same colour or somewhat lighter.
The geographically closest relative is the Rarotonga starling, which is larger and has a greyish body plumage with light grey feather margins. In overall appearance, A. mavornata is closest to the Polynesian starling's subspecies tenebrosus of Niuatoputapu and Tafahi, Tonga; alternatively, it looks much like a much (nearly one-third) smaller, yellow-eyed version of the Samoan starling.
Extinction
There is a lot of mystery surrounding the Mauke Starling. The only known specimen (BMNH Old Vellum Catalog 12.192) was shot "hopping about [on a] tree", by Andrew Bloxam, naturalist of HMS Blonde, roughly between 2:30 and 3:30 pm on August 9, 1825. The island of Mauke was not visited again by ornithologists until 1973, by which time the bird was extinct, presumably due to predation by introduced rats. Bloxam noted that in 1825, only two years after the arrival of the first Europeans, they "saw quantities of rats with long tails, different in appearance from the common South Sea rat and resembling in colour and almost in size the Norway rat". Thus, and consider
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https://en.wikipedia.org/wiki/Extension%20topology
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In topology, a branch of mathematics, an extension topology is a topology placed on the disjoint union of a topological space and another set. There are various types of extension topology, described in the sections below.
Extension topology
Let X be a topological space and P a set disjoint from X. Consider in X ∪ P the topology whose open sets are of the form A ∪ Q, where A is an open set of X and Q is a subset of P.
The closed sets of X ∪ P are of the form B ∪ Q, where B is a closed set of X and Q is a subset of P.
For these reasons this topology is called the extension topology of X plus P, with which one extends to X ∪ P the open and the closed sets of X. As subsets of X ∪ P the subspace topology of X is the original topology of X, while the subspace topology of P is the discrete topology. As a topological space, X ∪ P is homeomorphic to the topological sum of X and P, and X is a clopen subset of X ∪ P.
If Y is a topological space and R is a subset of Y, one might ask whether the extension topology of Y – R plus R is the same as the original topology of Y, and the answer is in general no.
Note the similarity of this extension topology construction and the Alexandroff one-point compactification, in which case, having a topological space X which one wishes to compactify by adding a point ∞ in infinity, one considers the closed sets of X ∪ {∞} to be the sets of the form K, where K is a closed compact set of X, or B ∪ {∞}, where B is a closed set of X.
Open extension topology
Let be a topological space and a set disjoint from . The open extension topology of plus is Let . Then is a topology in . The subspace topology of is the original topology of , i.e. , while the subspace topology of is the discrete topology, i.e. .
The closed sets in are . Note that is closed in and is open and dense in .
If Y a topological space and R is a subset of Y, one might ask whether the open extension topology of Y – R plus R is the same as the original topology
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https://en.wikipedia.org/wiki/Michael%20Bartosh
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Michael Bartosh (September 18, 1977 – June 11, 2006) was president and CTO of 4am Media, Inc, an Apple Certified Trainer, certified member of the Apple Consultants Network, published author and former systems engineer for Apple Computer. Previous to joining Apple full-time he had worked as an Apple campus rep (at Texas A&M) and had the opportunity to meet Steve Jobs after his 1999 MacWorld keynote. His main focus and expertise was directory services and integration, and was considered by members of the Macintosh support and development community to be one of the foremost experts on the subject, having literally "written the book."
His most recent work includes Mac OS X Tiger Server Administration (published posthumously), Essential Mac OS X Panther Server Administration, articles published on O'Reilly network (Open Directory and Active Directory parts 1-4 and Panther and Active Directory ), as well as presentations and classes at many training centers/events, trade shows and conferences.
He was also a regular contributor on several technical mailing lists related to Mac OS X and Mac OS X Server.
Death
He died as a result of injuries caused by a fall from a balcony at a friend's home in Tokyo in June 2006.
Police ruled the death an accident. The Michael Bartosh Memorial Scholarship was created in his honor.
Bibliography
Mac OS X Tiger Server Administration, O'Reilly Media, September 2006,
Essential Mac OS X Panther Server Administration, O'Reilly Media, May 2005,
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https://en.wikipedia.org/wiki/Period-after-opening%20symbol
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The period-after-opening symbol or PAO symbol is a graphic symbol that identifies the useful lifetime of a cosmetic product after its package has been opened for the first time. It depicts an open cosmetics pot and is used together with a written number of months or years.
In the European Union, cosmetics products with a shelf-life of at least 30 months are not required to carry a "best used before end of ..." date. Instead, there has to be "an indication of the period of time after opening for which the product can be used without any harm to the consumer". The EU Cosmetics Directive defines in Annex VIIIa the language-neutral open-jar symbol, which manufacturers should use to indicate this period.
The time period is most often represented compactly as a number of months, followed by the letter "M", as in "36M" for a period of thirty-six months, written either onto the front side of the depicted pot or to the right or bottom of it. The letter "M" is the initial for the word month not only in English, but also in many other European languages. It is also used in the ISO 8601 duration notation.
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https://en.wikipedia.org/wiki/Anterior%20sacroiliac%20ligament
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The anterior sacroiliac ligament consists of numerous thin bands, which connect the anterior surface of the lateral part of the sacrum to the margin of the auricular surface of the ilium and to the preauricular sulcus.
See also
Posterior sacroiliac ligament
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https://en.wikipedia.org/wiki/Posterior%20inferior%20iliac%20spine
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The posterior inferior iliac spine (Sweeney's Tubercle) is an anatomical landmark that describes a bony "spine", or projection, at the posterior and inferior surface of the iliac bone.
It is one of two such spines on the posterior surface, the other being the posterior superior iliac spine. These two spines are separated by a bony notch. They appear as two dimples in the skin, at the level of the lower back.
The posterior inferior iliac spine corresponds with the posterior extremity of the auricular surface.
Additional images
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https://en.wikipedia.org/wiki/Posterior%20superior%20iliac%20spine
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The posterior border of the ala, shorter than the anterior, also presents two projections separated by a notch, the posterior superior iliac spine and the posterior inferior iliac spine. The posterior superior iliac spine serves for the attachment of the oblique portion of the posterior sacroiliac ligaments and the multifidus.
See also
Dimples of Venus
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https://en.wikipedia.org/wiki/Iliac%20tuberosity
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Behind the iliac fossa is a rough surface, divided into two portions, an anterior and a posterior. The posterior portion, known as the iliac tuberosity, is elevated and rough, for the attachment of the posterior sacroiliac ligaments and for the origins of the sacrospinalis and multifidus.
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https://en.wikipedia.org/wiki/Posterior%20sacroiliac%20ligament
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The posterior sacroiliac ligament is situated in a deep depression between the sacrum and ilium behind; it is strong and forms the chief bond of union between the bones.
It consists of numerous fasciculi, which pass between the bones in various directions.
The upper part (short posterior sacroiliac ligament) is nearly horizontal in direction, and pass from the first and second transverse tubercles on the back of the sacrum to the tuberosity of the ilium.
The lower part (long posterior sacroiliac ligament) is oblique in direction; it is attached by one extremity to the third transverse tubercle of the back of the sacrum, and by the other to the posterior superior spine of the ilium.
See also
Anterior sacroiliac ligament
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https://en.wikipedia.org/wiki/Test%20register
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A test register, in the Intel 80386 and Intel 80486 processor, was a register used by the processor, usually to do a self-test. Most of these registers were undocumented, and used by specialized software. The test registers were named TR3 to TR7. Regular programs don't usually require these registers to work. With the Pentium, the test registers were replaced by a variety of model-specific registers (MSRs).
In the 80386, two test registers, TR6 and TR7, were provided for the purpose of TLB testing. TR6 was the test command register, and TR7 was the test data register. The 80486 provided three additional registers, TR3, TR4 and TR5, for testing of the L1 cache. TR3 was a data register, TR4 was an address register and TR5 was a command register. These registers were accessed by variants of the MOV instruction. A test register may either be the source operand or the destination operand. The MOV instructions are defined in both real-address mode and protected mode. The test registers are privileged resources. In protected mode, the MOV instructions that access them can only be executed at privilege level 0. An attempt to read or write the test registers when executing at any other privilege level causes a general protection exception. Also, those instructions generate invalid opcode exception on most CPUs newer than 80486.
The instruction is encoded in two ways, depending on the flow of data. Moving data from a general purpose register into a test register is encoded as 0F 26 /r (with r/m being the GPR, and reg being the test register). Moving data the other way (i.e. from the test register into a general purpose register) is encoded as 0F 24 /r (with r/m being the GPR, and reg being the test register). Only register-register moves are allowed; memory forms of the ModR/M byte are undefined. In other words, the mod field (the two MSBs) must be set to 1.
The test registers and/or associated opcodes were supported in the following x86 processors:
See also
Control reg
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