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https://en.wikipedia.org/wiki/Neural%20tube%20defect | Neural tube defects (NTDs) are a group of birth defects in which an opening in the spine or cranium remains from early in human development. In the third week of pregnancy called gastrulation, specialized cells on the dorsal side of the embryo begin to change shape and form the neural tube. When the neural tube does not close completely, an NTD develops.
Specific types include: spina bifida which affects the spine, anencephaly which results in little to no brain, encephalocele which affects the skull, and iniencephaly which results in severe neck problems.
NTDs are one of the most common birth defects, affecting over 300,000 births each year worldwide. For example, spina bifida affects approximately 1,500 births annually in the United States, or about 3.5 in every 10,000 (0.035% of US births), which has decreased from around 5 per 10,000 (0.05% of US births) since folate fortification of grain products was started. The number of deaths in the US each year due to neural tube defects also declined from 1,200 before folate fortification was started to 840.
Types
There are two classes of NTDs: open, which are more common, and closed. Open NTDs occur when the brain and/or spinal cord are exposed at birth through a defect in the skull or vertebrae (spinal column). Open NTDs include anencephaly, encephaloceles, hydranencephaly, iniencephaly, schizencephaly, and the most common form, spina bifida. Closed NTDs occur when the spinal defect is covered by skin. Types of closed NTDs include lipomeningocele, lipomyelomeningocele, and tethered cord.
Anencephaly
Anencephaly (without brain) is a severe neural tube defect that occurs when the anterior-most end of the neural tube fails to close, usually during the 23rd and 26th days of pregnancy. This results in an absence of a major portion of the brain and skull. Infants born with this condition lack the main part of the forebrain and are usually blind, deaf and display major craniofacial anomalies. The lack of a functioning ce |
https://en.wikipedia.org/wiki/Cementoblast | A cementoblast is a biological cell that forms from the follicular cells around the root of a tooth, and whose biological function is cementogenesis, which is the formation of cementum (hard tissue that covers the tooth root). The mechanism of differentiation of the cementoblasts is controversial but circumstantial evidence suggests that an epithelium or epithelial component may cause dental sac cells to differentiate into cementoblasts, characterised by an increase in length. Other theories involve Hertwig epithelial root sheath (HERS) being involved.
Structure
Thus cementoblasts resemble bone-forming osteoblasts but differ functionally and histologically. The cells of cementum are the entrapped cementoblasts, the cementocytes. Each cementocyte lies in its lacuna (plural, lacunae), similar to the pattern noted in bone. These lacunae also have canaliculi or canals. Unlike those in bone, however, these canals in cementum do not contain nerves, nor do they radiate outward. Instead, the canals are oriented toward the periodontal ligament (PDL) and contain cementocytic processes that exist to diffuse nutrients from the ligament because it is vascularized. The progenitor cells also found in the PDL region contribute to the mineralization of the tissue.
Once in this situation, cementoblasts lose their secretory activity and become cementocytes. However, a layer of cementoblasts is always present along the outer covering of the PDL; these cells can then produce cementum if the tooth is injured (see hypercementosis).
See also
Cementum
Cementogenesis
Tooth development
Cementoblastoma
Enamel
List of human cell types derived from the germ layers
List of distinct cell types in the adult human body |
https://en.wikipedia.org/wiki/MIPS-X | MIPS-X is a reduced instruction set computer (RISC) microprocessor and instruction set architecture (ISA) developed as a follow-on project to the MIPS project at Stanford University by the same team that developed MIPS. The project, supported by the Defense Advanced Research Projects Agency (DARPA), began in 1984, and its final form was described in a set of papers released in 1986–87. Unlike its older cousin, MIPS-X was never commercialized as a workstation central processing unit (CPU), and has mainly been seen in embedded system designs based on chips designed by Integrated Information Technology (IIT) for use in digital video applications.
MIPS-X, while designed by the same team and architecturally very similar, is instruction-set incompatible with the mainline MIPS architecture R-series processors. The MIPS-X processor is obscure enough that, as of November 20, 2005, support for it is provided only by specialist developers (such as Green Hills Software), and is notably missing from the GNU Compiler Collection (GCC).
MIPS-X has become important among DVD player firmware hackers, since many DVD players (especially low-end devices) use chips based on the IIT design (and produced by ESS Technology), as their central processor. Devices such as the ESS VideoDrive system on a chip (SoC) also include a digital signal processor (DSP) (coprocessor) for decoding MPEG audio and video streams.
External links
The original MIPS-X paper from Stanford
Instruction set architectures
MIPS architecture
Stanford University
32-bit microprocessors |
https://en.wikipedia.org/wiki/Archicembalo | The archicembalo (or arcicembalo, ) was a musical instrument described by Nicola Vicentino in 1555. This was a harpsichord built with many extra keys and strings, enabling experimentation in microtonality and just intonation.
Construction
The archicembalo had two manuals, but unlike those on a normal harpsichord these two keyboards were used to provide extra pitches rather than a timbral difference. Both manuals contained all of the usual white and black keys, but in addition each black key was divided into two parts so that a distinction could be made between a sharp or flat note. The lower manual also included black keys between B and C, and between E and F. In total, 36 keys were available in any octave, each of which was tuned to a different pitch, as shown in the diagram of the lower manual.
Tuning
There were two systems of tuning the archicembalo considered by Vicentino:
The most important was the extended quarter-comma meantone temperament—which, given such a wide gamut of fifths, becomes almost exactly a system of 31 equal divisions of the octave (see 31 equal temperament). This arises because after a cycle of 31 quarter-comma-tempered fifths, the 32nd pitch is remarkably close to a pitch that already exists in the system. Thus, five of Vicentino's 36 possibilities became practically redundant in this system. He suggested that these five be tuned instead according to the second manner described below.
Vicentino offered an alternative tuning in which the upper keyboard was tuned a quarter-comma higher than the lower, allowing pure fifths by playing chords across the manuals, giving a limited system of triadic just intonation. This tuning still permits modulation to a wide range of keys, but not in a completely circular fashion as with the first tuning described above, and still only modulates by the meantone-tempered fifth, not by the pure fifth.
The observation that extended quarter-comma meantone temperament almost exactly approximates 31 equal was |
https://en.wikipedia.org/wiki/Amagat | An amagat is a practical unit of volumetric number density. Although it can be applied to any substance at any conditions, it is defined as the number of ideal gas molecules per unit volume at 1 atm (101.325 kPa) and 0 °C (273.15 K). It is named after Émile Amagat, who also has Amagat's law named after him. The abbreviated form of amagat is "amg". The abbreviation "Am" has also been used.
SI conversion
The amg unit for number density can be converted to the SI unit mol/m3 by the formula
where ≘ indicates correspondence, since the SI unit is of molar concentration and not number density.
The conversion factor (44.615...) is called the Loschmidt number.
The number density of an ideal gas at pressure p and temperature T can be calculated as
where T0 = 273.15 K, and p0 = 101.325 kPa (STP before 1982).
Example
Number density of an ideal gas (such as air) at room temperature (20 °C) and 1 atm (101.325 kPa) is |
https://en.wikipedia.org/wiki/Bragg%20plane | In physics, a Bragg plane is a plane in reciprocal space which bisects a reciprocal lattice vector, , at right angles. The Bragg plane is defined as part of the Von Laue condition for diffraction peaks in x-ray diffraction crystallography.
Considering the adjacent diagram, the arriving x-ray plane wave is defined by:
Where is the incident wave vector given by:
where is the wavelength of the incident photon. While the Bragg formulation assumes a unique choice of direct lattice planes and specular reflection of the incident X-rays, the Von Laue formula only assumes monochromatic light and that each scattering center acts as a source of secondary wavelets as described by the Huygens principle. Each scattered wave contributes to a new plane wave given by:
The condition for constructive interference in the direction is that the path difference between the photons is an integer multiple (m) of their wavelength. We know then that for constructive interference we have:
where . Multiplying the above by we formulate the condition in terms of the wave vectors, and :
Now consider that a crystal is an array of scattering centres, each at a point in the Bravais lattice. We can set one of the scattering centres as the origin of an array. Since the lattice points are displaced by the Bravais lattice vectors, , scattered waves interfere constructively when the above condition holds simultaneously for all values of which are Bravais lattice vectors, the condition then becomes:
An equivalent statement (see mathematical description of the reciprocal lattice) is to say that:
By comparing this equation with the definition of a reciprocal lattice vector, we see that constructive interference occurs if is a vector of the reciprocal lattice. We notice that and have the same magnitude, we can restate the Von Laue formulation as requiring that the tip of incident wave vector, , must lie in the plane that is a perpendicular bisector of the reciprocal lattice vector, . This rec |
https://en.wikipedia.org/wiki/Methoden%20der%20mathematischen%20Physik | Methoden der mathematischen Physik (Methods of Mathematical Physics) is a 1924 book, in two volumes totalling around 1000 pages, published under the names of Richard Courant and David Hilbert. It was a comprehensive treatment of the "methods of mathematical physics" of the time. The second volume is devoted to the theory of partial differential equations. It contains presages of the finite element method, on which Courant would work subsequently, and which would eventually become basic to numerical analysis.
The material of the book was worked up from the content of Hilbert's lectures. While Courant played the major editorial role, many at the University of Göttingen were involved in the writing-up, and in that sense it was a collective production.
On its appearance in 1924 it apparently had little direct connection to the quantum theory questions at the centre of the theoretical physics of the time. That changed within two years, since the formulation of Schrödinger's equation made the Hilbert-Courant techniques of immediate relevance to the new wave mechanics.
There was a second edition (1931/7), wartime edition in the USA (1943), and a third German edition (1968). The English version Methods of Mathematical Physics (1953) was revised by Courant, and the second volume had extensive work done on it by the faculty of the Courant Institute. The books quickly gained the reputation as classics, and are among most highly referenced books in advanced mathematical physics courses. |
https://en.wikipedia.org/wiki/Silver%20Spring%20monkeys | The Silver Spring monkeys were 17 wild-born macaque monkeys from the Philippines who were kept in the Institute for Behavioral Research in Silver Spring, Maryland. From 1981 until 1991, they became what one writer called the most famous lab animals in history, as a result of a battle between animal researchers, animal advocates, politicians, and the courts over whether to use them in research or release them to a sanctuary. Within the scientific community, the monkeys became known for their use in experiments into neuroplasticity—the ability of the adult primate brain to reorganize itself.
The monkeys had been used as research subjects by Edward Taub, a psychologist, who had cut afferent ganglia that supplied sensation to the brain from their arms, then used arm slings to restrain either the good or deafferented arm to train them to use the limbs they could not feel. In May 1981, Alex Pacheco of the animal-rights group People for the Ethical Treatment of Animals (PETA) began working undercover in the lab, and alerted police to what PETA viewed as unacceptable living conditions for the monkeys. In what was the first police raid in the U.S. against an animal researcher, police entered the Institute and removed the monkeys, charging Taub with 17 counts of animal cruelty and failing to provide adequate veterinary care. He was convicted on six counts; five were overturned during a second trial, and the final conviction was overturned on appeal in 1983, when the court ruled that Maryland's animal cruelty legislation did not apply to federally funded laboratories.
The ensuing battle over the monkeys' custody saw celebrities and politicians campaign for the monkeys' release, an amendment in 1985 to the Animal Welfare Act, the transformation of PETA from a group of friends into a national movement, the creation of the first North American Animal Liberation Front cell, and the first animal research case to reach the United States Supreme Court. In July 1991, PETA's applica |
https://en.wikipedia.org/wiki/Stefan%20Cohn-Vossen | Stefan Cohn-Vossen (28 May 1902 – 25 June 1936) was a mathematician, who was responsible for Cohn-Vossen's inequality and the Cohn-Vossen transformation is also named for him. He proved the first version of the splitting theorem.
He was also known for his collaboration with David Hilbert on the 1932 book Anschauliche Geometrie, translated into English as Geometry and the Imagination.
He was born in Breslau (then a city in the Kingdom of Prussia; now Wrocław in Poland). He wrote a 1924 doctoral dissertation at the University of Breslau (now the University of Wrocław) under the supervision of Adolf Kneser. He became a professor at the University of Cologne in 1930.
He was barred from lecturing in 1933 under Nazi racial legislation, because he was Jewish. In 1934 he emigrated to the USSR, with some help from Herman Müntz. While there, he taught at Leningrad University. He died in Moscow from pneumonia.
See also
Cohn-Vossen's inequality |
https://en.wikipedia.org/wiki/M%C3%BCntz%E2%80%93Sz%C3%A1sz%20theorem | The Müntz–Szász theorem is a basic result of approximation theory, proved by Herman Müntz in 1914 and Otto Szász (1884–1952) in 1916. Roughly speaking, the theorem shows to what extent the Weierstrass theorem on polynomial approximation can have holes dug into it, by restricting certain coefficients in the polynomials to be zero. The form of the result had been conjectured by Sergei Bernstein before it was proved.
The theorem, in a special case, states that a necessary and sufficient condition for the monomials
to span a dense subset of the Banach space C[a,b] of all continuous functions with complex number values on the closed interval [a,b] with a > 0, with the uniform norm, is that the sum
of the reciprocals, taken over S, should diverge, i.e. S is a large set. For an interval [0, b], the constant functions are necessary: assuming therefore that 0 is in S, the condition on the other exponents is as before.
More generally, one can take exponents from any strictly increasing sequence of positive real numbers, and the same result holds. Szász showed that for complex number exponents, the same condition applied to the sequence of real parts.
There are also versions for the Lp spaces.
See also
Erdős conjecture on arithmetic progressions |
https://en.wikipedia.org/wiki/F.%20and%20M.%20Riesz%20theorem | In mathematics, the F. and M. Riesz theorem is a result of the brothers Frigyes Riesz and Marcel Riesz, on analytic measures. It states that for a measure μ on the circle, any part of μ that is not absolutely continuous with respect to the Lebesgue measure dθ can be detected by means of Fourier coefficients.
More precisely, it states that if the Fourier–Stieltjes coefficients of
satisfy
for all ,
then μ is absolutely continuous with respect to dθ.
The original statements are rather different (see Zygmund, Trigonometric Series, VII.8). The formulation here is as in Walter Rudin, Real and Complex Analysis, p.335. The proof given uses the Poisson kernel and the existence of boundary values for the Hardy space H1.
Expansions to this theorem were made by James E. Weatherbee in his 1968 dissertation: Some Extensions Of The F. And M. Riesz Theorem On Absolutely Continuous Measures. |
https://en.wikipedia.org/wiki/Heliospheric%20current%20sheet | The heliospheric current sheet, or interplanetary current sheet, is a surface separating regions of the heliosphere where the interplanetary magnetic field points toward and away from the Sun. A small electrical current with a current density of about 10−10 A/m2 flows within this surface, forming a current sheet confined to this surface. The shape of the current sheet results from the influence of the Sun's rotating magnetic field on the plasma in the interplanetary medium. The thickness of the current sheet is about near the orbit of the Earth.
Characteristics
Ballerina's skirt shape
As the Sun rotates, its magnetic field twists into an Archimedean spiral, as it extends through the Solar System. This phenomenon is often called the Parker spiral, after Eugene Parker's work that predicted the structure of the interplanetary magnetic field.
The spiral nature of the heliospheric magnetic field was noted earlier by Hannes Alfvén, based on the structure of comet tails.
The influence of this spiral-shaped magnetic field on the interplanetary medium (solar wind) creates the largest structure in the Solar System, the heliospheric current sheet.
Parker's spiral magnetic field was divided in two by a current sheet, a mathematical model first developed in the early 1970s by Schatten. It warps into a wavy spiral shape that has been likened to a ballerina's skirt. The waviness of the current sheet is due to the magnetic field dipole axis' tilt angle to the solar rotation axis and variations from an ideal dipole field.
Unlike the familiar shape of the field from a bar magnet, the Sun's extended field is twisted into an arithmetic spiral by the magnetohydrodynamic influence of the solar wind. The solar wind travels outward from the Sun at a rate of 200-800km/s, but an individual jet of solar wind from a particular feature on the Sun's surface rotates with the solar rotation, making a spiral pattern in space. The cause of this ballerina spiral shape has sometimes been calle |
https://en.wikipedia.org/wiki/Lymphocytopenia | Lymphocytopenia is the condition of having an abnormally low level of lymphocytes in the blood. Lymphocytes are a white blood cell with important functions in the immune system. It is also called lymphopenia. The opposite is lymphocytosis, which refers to an excessive level of lymphocytes.
Lymphocytopenia may be present as part of a pancytopenia, when the total numbers of all types of blood cells are reduced.
Classification
In some cases, lymphocytopenia can be further classified according to which kind of lymphocytes are reduced. If all three kinds of lymphocytes are suppressed, then the term is used without further qualification.
In T lymphocytopenia, there are too few T lymphocytes, but normal numbers of other lymphocytes. It causes, and manifests as, a T cell deficiency. This is usually caused by HIV infection (resulting in AIDS), but may be Idiopathic CD4+ lymphocytopenia (ICL), which is a very rare heterogeneous disorder defined by CD4+ T-cell counts below 300 cells/μL in the absence of any known immune deficiency condition, such as human immunodeficiency virus (HIV) infection or chemotherapy.
In B lymphocytopenia, there are too few B lymphocytes, but possibly normal numbers of other lymphocytes. It causes, and manifests as, a humoral immune deficiency. This is usually caused by medications that suppress the immune system.
In NK lymphocytopenia, there are too few natural killer cells, but normal numbers of other lymphocytes. This is very rare.
Causes
The most common cause of temporary lymphocytopenia is a recent infection, such as the common cold.
Lymphocytopenia, but not idiopathic CD4+ lymphocytopenia, is associated with corticosteroid use, infections with HIV and other viral, bacterial, and fungal agents, malnutrition, systemic lupus erythematosus, severe stress, intense or prolonged physical exercise (due to cortisol release), rheumatoid arthritis, sarcoidosis, multiple sclerosis, and iatrogenic (caused by other medical treatments) conditions.
|
https://en.wikipedia.org/wiki/ASTOS | ASTOS is a tool dedicated to mission analysis, Trajectory optimization, vehicle design and simulation for space scenarios, i.e. launch, re-entry missions, orbit transfers, Earth observation, navigation, coverage and re-entry safety assessments. It solves Aerospace problems with a data driven interface and automatic initial guesses. Since 1989, with the support of the European Space Agency, it has developed, and improved this trajectory optimization environment to compute optimal trajectories for a variety of complex multi-phase Optimal control problems. ASTOS is being extensively used at ESA and aerospace industry community to calculate mission analysis, optimal launch and entry trajectories and was one of the tools used by ESA to assess the risk due to the ATV 'Jules Verne' re-entry. ASTOS is compatible with Windows and Linux platforms and is maintained and commercialized by Astos Solutions GmbH.
History
The development of ASTOS (formerly named ALTOS) started in 1989 at the DLR in Oberpfaffenhofen and MBB (now Astrium).
In 1991 the Institute of Flight Mechanics and Control (IFR) at the University of Stuttgart under the head of Prof. Klaus Well took the responsibility for the development of ASTOS. In 1999 the commercialization of ASTOS began. In the period 2001-2006 ASTOS was sold by Technology Transfer Initiative of the University of Stuttgart (TTI). Since September 2006, the newly founded company Astos Solutions GmbH is responsible for development and sales of ASTOS.
Projects
ASTOS is being extensively used in aerospace agencies and industry since 1998, hereafter a not complete list of project is presented where the software was involved during the design or accomplishment of the space mission.
Performance map of conventional launch vehicle: Ariane 6, Ariane 5, Vega, Soyuz from Guiana Space Centre, several FLPP concepts, VLM
Feasibility study of reusable launch vehicle: Hopper, Skylon, SpaceLiner, Fast 20XX ALPHA.
Earth Atmospheric re-entry: X-38, Atmospheri |
https://en.wikipedia.org/wiki/Gustav%20Bergmann | Gustav Bergmann (May 4, 1906 – April 21, 1987) was an Austrian-born American philosopher. He studied at the University of Vienna and was a member of the Vienna Circle. Bergmann was influenced by the philosophers Moritz Schlick, Friedrich Waismann, and Rudolf Carnap, who were members of the Circle. In the United States, he was a professor of philosophy and psychology at the University of Iowa.
Biography
Bergmann was born in Vienna, Austria-Hungary. He earned his Ph.D. in mathematics at the University of Vienna in 1928. His dissertation, directed by Walther Mayer, was titled Zwei Beiträge zur mehrdimensionalen Differentialgeometrie. While studying for his doctorate, he was invited to join the Vienna Circle, a group of philosophers, mathematicians, scientists, and others committed to a scientific worldview under the name of logical positivism. In 1930–31, he worked with Albert Einstein in Berlin. Unable as a Jew to find academic employment, Bergmann obtained a J.D. degree from the University of Vienna in 1935, and practiced corporate law until he and his family fled to the United States in 1938. Settling at the University of Iowa in Iowa City in 1939, Bergmann eventually became professor of both philosophy and psychology.
He died in Iowa City.
Bibliography
The Metaphysics of Logical Positivism. New York: Longmans, Green & Co. 1954. (Second edition: Madison, University of Wisconsin Press, 1967.)
Philosophy of Science. Madison: University of Wisconsin Press 1957.
Meaning and Existence. Madison: University of Wisconsin Press 1959.
Logic and Reality. Madison: University of Wisconsin Press 1964.
Realism: A Critique of Brentano and Meinong. Madison: University of Wisconsin Press 1967.
New Foundations of Ontology. Madison: University of Wisconsin Press 1992. Edited by William Heald.
Collected Works. Vol I. II. Frankfurt am Main: Ontos Verlag 2003.
See also
American philosophy
List of American philosophers |
https://en.wikipedia.org/wiki/Neutron%20poison | In applications such as nuclear reactors, a neutron poison (also called a neutron absorber or a nuclear poison) is a substance with a large neutron absorption cross-section. In such applications, absorbing neutrons is normally an undesirable effect. However, neutron-absorbing materials, also called poisons, are intentionally inserted into some types of reactors in order to lower the high reactivity of their initial fresh fuel load. Some of these poisons deplete as they absorb neutrons during reactor operation while others remain relatively constant.
The capture of neutrons by short half-life fission products is known as reactor poisoning; neutron capture by long-lived or stable fission products is called reactor slagging.
Transient fission product poisons
Some of the fission products generated during nuclear reactions have a high neutron absorption capacity, such as xenon-135 (microscopic cross-section σ = 2,000,000 barns (b); up to 3 million barns in reactor conditions) and samarium-149 (σ = 74,500 b). Because these two, fission-product poisons remove neutrons from the reactor, they will affect the thermal utilization factor and, thus, the reactivity. The poisoning of a reactor core by these fission products may become so serious that the chain reaction comes to a standstill.
Xenon-135 in particular tremendously affects the operation of a nuclear reactor because it is the most powerful, known, neutron poison. The inability of a reactor to be restarted due to the buildup of xenon-135 (reaches a maximum after about 10 hours) is sometimes referred to as xenon-precluded start-up. The period of time in which the reactor is unable to override the effects of xenon-135 is called the xenon dead time or poison outage. During periods of steady state operation, at a constant neutron flux level, the xenon-135 concentration builds up to its equilibrium value for that reactor power in about 40 to 50 hours. When the reactor power is increased, xenon-135 concentration initially |
https://en.wikipedia.org/wiki/Immunoproliferative%20disorder | In immunology, immunoproliferative disorders are disorders of the immune system that are characterized by the abnormal proliferation of the primary cells of the immune system, which includes B cells, T cells and natural killer (NK) cells, or by the excessive production of immunoglobulins (also known as antibodies).
Classes
These disorders are subdivided into three main classes, which are lymphoproliferative disorders, hypergammaglobulinemia, and paraproteinemia. The first is cellular, and the other two are humoral (however, humoral excess can be secondary to cellular excess.)
Lymphoproliferative disorders (LPDs) refer to several conditions in which lymphocytes are produced in excessive quantities. They typically occur in patients who have compromised immune systems. This subset is sometimes incorrectly equated with "immunoproliferative disorders".
Humoral
Hypergammaglobulinemia is characterized by increased levels of immunoglobulins in the blood serum. Five different hypergammaglobulinemias are caused by an excess of immunoglobulin M (IgM), and some types are caused by a deficiency in the other major types of immunoglobulins.
Paraproteinemia or monoclonal gammopathy is the presence of excessive amounts of a single monoclonal gammaglobulin (called a paraprotein) in the blood.
See also
Myeloproliferative disease |
https://en.wikipedia.org/wiki/Bergman%20kernel | In the mathematical study of several complex variables, the Bergman kernel, named after Stefan Bergman, is the reproducing kernel for the Hilbert space (RKHS) of all square integrable holomorphic functions on a domain D in Cn.
In detail, let L2(D) be the Hilbert space of square integrable functions on D, and let L2,h(D) denote the subspace consisting of holomorphic functions in L2(D): that is,
where H(D) is the space of holomorphic functions in D. Then L2,h(D) is a Hilbert space: it is a closed linear subspace of L2(D), and therefore complete in its own right. This follows from the fundamental estimate, that for a holomorphic square-integrable function ƒ in D
for every compact subset K of D. Thus convergence of a sequence of holomorphic functions in L2(D) implies also compact convergence, and so the limit function is also holomorphic.
Another consequence of () is that, for each z ∈ D, the evaluation
is a continuous linear functional on L2,h(D). By the Riesz representation theorem, this functional can be represented as the inner product with an element of L2,h(D), which is to say that
The Bergman kernel K is defined by
The kernel K(z,ζ) is holomorphic in z and antiholomorphic in ζ, and satisfies
One key observation about this picture is that L2,h(D) may be identified with the space of holomorphic (n,0)-forms on D, via multiplication by . Since the inner product on this space is manifestly invariant under biholomorphisms of D, the Bergman kernel and the associated Bergman metric are therefore automatically invariant under the automorphism group of the domain.
See also
Bergman metric
Bergman space
Szegő kernel |
https://en.wikipedia.org/wiki/Bergman%20space | In complex analysis, functional analysis and operator theory, a Bergman space, named after Stefan Bergman, is a function space of holomorphic functions in a domain D of the complex plane that are sufficiently well-behaved at the boundary that they are absolutely integrable. Specifically, for , the Bergman space is the space of all holomorphic functions in D for which the p-norm is finite:
The quantity is called the norm of the function ; it is a true norm if . Thus is the subspace of holomorphic functions that are in the space Lp(D). The Bergman spaces are Banach spaces, which is a consequence of the estimate, valid on compact subsets K of D:
Thus convergence of a sequence of holomorphic functions in implies also compact convergence, and so the limit function is also holomorphic.
If , then is a reproducing kernel Hilbert space, whose kernel is given by the Bergman kernel.
Special cases and generalisations
If the domain is bounded, then the norm is often given by:
where is a normalised Lebesgue measure of the complex plane, i.e. . Alternatively is used, regardless of the area of .
The Bergman space is usually defined on the open unit disk of the complex plane, in which case . In the Hilbert space case, given:, we have:
that is, is isometrically isomorphic to the weighted ℓp(1/(n + 1)) space. In particular the polynomials are dense in . Similarly, if , the right (or the upper) complex half-plane, then:
where , that is, is isometrically isomorphic to the weighted Lp1/t (0,∞) space (via the Laplace transform).
The weighted Bergman space is defined in an analogous way, i.e.,
provided that is chosen in such way, that is a Banach space (or a Hilbert space, if ). In case where , by a weighted Bergman space we mean the space of all analytic functions such that:
and similarly on the right half-plane (i.e., ) we have:
and this space is isometrically isomorphic, via the Laplace transform, to the space , where:
(here denotes the Gamma function).
F |
https://en.wikipedia.org/wiki/Syntax%20%28programming%20languages%29 | In computer science, the syntax of a computer language is the rules that define the combinations of symbols that are considered to be correctly structured statements or expressions in that language. This applies both to programming languages, where the document represents source code, and to markup languages, where the document represents data.
The syntax of a language defines its surface form. Text-based computer languages are based on sequences of characters, while visual programming languages are based on the spatial layout and connections between symbols (which may be textual or graphical). Documents that are syntactically invalid are said to have a syntax error. When designing the syntax of a language, a designer might start by writing down examples of both legal and illegal strings, before trying to figure out the general rules from these examples.
Syntax therefore refers to the form of the code, and is contrasted with semantics – the meaning. In processing computer languages, semantic processing generally comes after syntactic processing; however, in some cases, semantic processing is necessary for complete syntactic analysis, and these are done together or concurrently. In a compiler, the syntactic analysis comprises the frontend, while the semantic analysis comprises the backend (and middle end, if this phase is distinguished).
Levels of syntax
Computer language syntax is generally distinguished into three levels:
Words – the lexical level, determining how characters form tokens;
Phrases – the grammar level, narrowly speaking, determining how tokens form phrases;
Context – determining what objects or variables names refer to, if types are valid, etc.
Distinguishing in this way yields modularity, allowing each level to be described and processed separately and often independently. First, a lexer turns the linear sequence of characters into a linear sequence of tokens; this is known as "lexical analysis" or "lexing". Second, the parser turns the linea |
https://en.wikipedia.org/wiki/Biological%20half-life | Biological half-life (elimination half-life, pharmacological half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration (Cmax) to half of Cmax in the blood plasma. It is denoted by the abbreviation .
This is used to measure the removal of things such as metabolites, drugs, and signalling molecules from the body. Typically, the biological half-life refers to the body's natural detoxification (cleansing) through liver metabolism and through the excretion of the measured substance through the kidneys and intestines. This concept is used when the rate of removal is roughly exponential.
In a medical context, half-life explicitly describes the time it takes for the blood plasma concentration of a substance to halve (plasma half-life) its steady-state when circulating in the full blood of an organism. This measurement is useful in medicine, pharmacology and pharmacokinetics because it helps determine how much of a drug needs to be taken and how frequently it needs to be taken if a certain average amount is needed constantly. By contrast, the stability of a substance in plasma is described as plasma stability. This is essential to ensure accurate analysis of drugs in plasma and for drug discovery.
The relationship between the biological and plasma half-lives of a substance can be complex depending on the substance in question, due to factors including accumulation in tissues, protein binding, active metabolites, and receptor interactions.
Examples
Water
The biological half-life of water in a human is about 7 to 14 days. It can be altered by behavior. Drinking large amounts of alcohol will reduce the biological half-life of water in the body. This has been used to decontaminate patients who are internally contaminated with tritiated water. The basis of this decontamination method is to increase the rate at which the water in the body is replaced with new water.
Alcohol
The removal of ethan |
https://en.wikipedia.org/wiki/Electronic%20Frontiers%20Georgia | Electronic Frontiers Georgia (EFGA) is a non-profit organization in the US state of Georgia focusing on issues related to cyber law and free speech. It was founded in 1995 by Tom Cross, Robert Costner, Chris Farris, and Robbie Honerkamp, primarily in response to the Communications Decency Act.
One of the organization's early causes was to oppose Georgia House Bill 1630 (HB1630), an attempt to ban anonymous speech on the internet in Georgia. Though the bill was passed into law, after being challenged in court by the EFGA, the ACLU, and the national Electronic Frontier Foundation (EFF), the law was deemed unconstitutional.
Origins
Electronic Frontiers Georgia began after a suggestion by Stanton McCandlish of the EFF in conversations with Atlanta businessman and computer store owner Robert Costner. Costner expressed concern after Philip Elmer-DeWitt's Time magazine article claimed that pornography was pervasive on the internet. Costner was angered because he thought the article was bogus. While DeWitt later apologized for the article, the "correction by Time sought to downplay, rather than apologize for, misleading their readers". It was a precursor to the Communications Decency Act.
Seeking partners to provide in-kind donations, Costner approached the Georgia ACLU for meeting space and Comstar, an internet hosting company, for rackspace for an internet server from Costner's store.
On local newsgroups Costner announced a public meeting to be held at the ACLU's downtown offices. From this, and similar meetings, Georgia residents joined in and became part of Electronic Frontiers Georgia. Most notable were Tom Cross, Chris Farris, and Robbie Honerkamp. At a later point Andy Dustman and Scott M. Jones joined the organization in significant capacities.
The EFGA's mission is to explore the intersection of public policy and technology.
Distinction from the EFF
Though often confused with the Electronic Frontier Foundation, the EFGA is a separate organization. The EFF i |
https://en.wikipedia.org/wiki/Linear%20alternator | A linear alternator is essentially a linear motor used as an electrical generator.
An alternator is a type of alternating current (AC) electrical generator. The devices are often physically equivalent. The principal difference is in how they are used and which direction the energy flows. An alternator converts mechanical energy to electrical energy, whereas a motor converts electrical energy to mechanical energy. Like many electric motors and electric generators, the linear alternator works by the principle of electromagnetic induction. However, most alternators work with rotary motion, whereas linear alternators work with linear motion (i.e. motion in a straight line).
Theory
A linear alternator is most commonly used to convert back-and-forth motion directly into electrical energy. This eliminates the need for a crank or linkage to convert a reciprocating motion to a rotary motion in order to drive a rotary generator.
Air compression generator
Mainspring Energy's linear generator uses a flameless reaction to efficiently convert chemical-bond energy into electricity. It is compatible with various fuels, including ammonia, and biogas, and hydrogen. The commercial device is double-ended. A translator on each end equipped with permanent magnets moves back and forth between the reaction chamber and a fixed-dimension box that functions as an air spring. Stationary copper coils surround each translator, forming a linear electromagnetic machine (LEM). Air and fuel are introduced into the center reaction chamber. Energy stored in the air springs from a previous cycle compresses the mixture until a flameless, exothermic reaction occurs. The reaction pushes the translators back through the copper coils, producing electricity. This motion recompresses the air springs, readying the system for the next cycle. Byproducts are water, nitrogen gas, and other substances. The reaction requires no spark/ignition source. A 115 kW machine extends 5.5 meters and is about 1 meter in di |
https://en.wikipedia.org/wiki/Viridiplantae | Viridiplantae (literally "green plants") constitute a clade of eukaryotic organisms that comprises approximately 450,000–500,000 species that play important roles in both terrestrial and aquatic ecosystems. They include the green algae, which are primarily aquatic, and the land plants (embryophytes), which emerged from within them. Green algae traditionally excludes the land plants, rendering them a paraphyletic group. However it is accurate to think of land plants as a kind of alga. Since the realization that the embryophytes emerged from within the green algae, some authors are starting to include them. They have cells with cellulose in their cell walls, and primary chloroplasts derived from endosymbiosis with cyanobacteria that contain chlorophylls a and b and lack phycobilins. Corroborating this, a basal phagotroph archaeplastida group has been found in the Rhodelphydia.
In some classification systems, the group has been treated as a kingdom, under various names, e.g. Viridiplantae, Chlorobionta, or simply Plantae, the latter expanding the traditional plant kingdom to include the green algae. Adl et al., who produced a classification for all eukaryotes in 2005, introduced the name Chloroplastida for this group, reflecting the group having primary chloroplasts with green chlorophyll. They rejected the name Viridiplantae on the grounds that some of the species are not plants, as understood traditionally. The Viridiplantae are made up of two clades: Chlorophyta and Streptophyta as well as the basal Mesostigmatophyceae and Chlorokybophyceae. Together with Rhodophyta and glaucophytes, Viridiplantae are thought to belong to a larger clade called Archaeplastida or Primoplantae.
Phylogeny and classification
Simplified phylogeny of the Viridiplantae, according to Leliaert et al. 2012.
Viridiplantae
Chlorophyta
core chlorophytes
Ulvophyceae
Cladophorales
Dasycladales
Bryopsidales
Trentepohliales
Ulvales-Ulotrichales
Oltmannsiellopsidales
Chlorophyceae
Oedogoniales
Chae |
https://en.wikipedia.org/wiki/Robotic%20paradigm | In robotics, a robotic paradigm is a mental model of how a robot operates. A robotic paradigm can be described by the relationship between the three basic elements of robotics: Sensing, Planning, and Acting. It can also be described by how sensory data is processed and distributed through the system, and where decisions are made.
Hierarchical/deliberative paradigm
The robot operates in a top-down fashion, heavy on planning.
The robot senses the world, plans the next action, acts; at each step the robot explicitly plans the next move.
All the sensing data tends to be gathered into one global world model.
The reactive paradigm
Sense-act type of organization.
The robot has multiple instances of Sense-Act couplings.
These couplings are concurrent processes, called behaviours, which take the local sensing data and compute the best action to take independently of what the other processes are doing.
The robot will do a combination of behaviours.
Hybrid deliberate/reactive paradigm
The robot first plans (deliberates) how to best decompose a task into subtasks (also called “mission planning”) and then what are the suitable behaviours to accomplish each subtask.
Then the behaviours starts executing as per the Reactive Paradigm.
Sensing organization is also a mixture of Hierarchical and Reactive styles; sensor data gets routed to each behaviour that needs that sensor, but is also available to the planner for construction of a task-oriented global world model.
See also
Behavior-based robotics
Hierarchical control system
Subsumption architecture |
https://en.wikipedia.org/wiki/Versit%20Consortium | The versit Consortium was a multivendor initiative founded by Apple Computer, AT&T, IBM and Siemens in the early 1990s in order to create Personal Data Interchange (PDI) technology, open specifications for exchanging personal data over the Internet, wired and wireless connectivity and Computer Telephony Integration (CTI). The Consortium started a number of projects to deliver open specifications aimed at creating industry standards.
Computer Telephony Integration
One of the most ambitious projects of the Consortium was the Versit CTI Encyclopedia (VCTIE), a 3,000 page, 6 volume set of specifications defining how computer and telephony systems are to interact and become interoperable. The Encyclopedia was built on existing technologies and specifications such as ECMA's call control specifications, TSAPI and industry expertise of the core technical team. The volumes are:
Volume 1, Concepts & Terminology
Volume 2, Configurations & Landscape
Volume 3, Telephony Feature Set
Volume 4, Call Flow Scenarios
Volume 5, CTI Protocols
Volume 6, Versit TSAPI
Appendices include:
Versit TSAPI header file
Protocol 1 ASN.1 description
Protocol 2 ASN.1 description
Versit Server Mapper Interface header file
Versit TSDI header file
The core Versit CTI Encyclopedia technical team was composed of David H. Anderson and Marcus W. Fath from IBM, Frédéric Artru and Michael Bayer from Apple Computer, James L. Knight and Steven Rummel from AT&T (then Lucent Technologies), Tom Miller from Siemens, and consultants Ellen Feaheny and Charles Hudson. Upon completion, the Versit CTI Encyclopedia was transferred to the ECTF and has been adopted in the form of ECTF C.001. This model represents the basis for the ECTF's call control efforts.
Though the Versit CTI Encyclopedia ended up influencing many products, there was one full compliant implementation of the specifications that was brought to market: Odisei, a French company founded by team member Frédéric Artru developed the IntraSw |
https://en.wikipedia.org/wiki/Walk%20percentage | Walk percentage (also known as Base-on-balls percentage, BB%, or BBP) is a baseball statistic criterion.
The purpose of this offensive measurement is to gauge the percentage of a batter's plate appearances that result in the player being walked. A more recently developed statistic than batting average, it is used to determine hitters that have a better plate discipline. |
https://en.wikipedia.org/wiki/Sign%20painting | Sign painting is the craft of painting lettered signs on buildings, billboards or signboards, for promoting, announcing, or identifying products, services and events. Sign painting artisans are signwriters.
History
Signwriters often learned the craft through apprenticeship or trade school, although many early sign painters were self-taught. The Sign Graphics program at the Los Angeles Trade Technical College program is the last remaining sign painting program in the United States.
Skillful manipulation of a lettering brush can take years to develop.
In the 1980s, with the advent of computer printing on vinyl, traditional hand-lettering faced stiff competition. Interest in the craft waned during the 1980s and 90s, but hand-lettering and traditional sign painting have experienced a resurgence in popularity in recent years.
The 2012 book and documentary, Sign Painters by Faythe Levine and Sam Macon, chronicle the historical changes and current state of the sign painting industry through personal interviews with contemporary sign painters.
Old painted signs which fade but remain visible are known as ghost signs.
Techniques
There are a number of other associated skills and techniques as well, including gold leafing (surface and glass), carving (in various mediums), glue-glass chipping, stencilling, and silk-screening.
Bibliography
Turvey, Lisa (April 2012). "An American Language". Artforum International. 50: 218–9.
Swezy, Tim (February 25, 2014). "One Shot Seen 'Round the World: A Survey of Sign Painting on the Internet (Part of AIGA Raleigh - the oldest and largest professional organization for Design)". AIGA Raleigh. Retrieved April 21, 2020.
Childs, Mark C. (2016). The Zeon files : art and design of historic Route 66 signs. Babcock, Ellen D., 1957-. Albuquerque: University of New Mexico Press. . OCLC 944156236.
Auer, Michael (1991). The Preservation of Historic Signs. Washington, D.C: U.S. Department of the Interior, National Park Service, Cultural Reso |
https://en.wikipedia.org/wiki/Krein%E2%80%93Milman%20theorem | In the mathematical theory of functional analysis, the Krein–Milman theorem is a proposition about compact convex sets in locally convex topological vector spaces (TVSs).
This theorem generalizes to infinite-dimensional spaces and to arbitrary compact convex sets the following basic observation: a convex (i.e. "filled") triangle, including its perimeter and the area "inside of it", is equal to the convex hull of its three vertices, where these vertices are exactly the extreme points of this shape.
This observation also holds for any other convex polygon in the plane
Statement and definitions
Preliminaries and definitions
Throughout, will be a real or complex vector space.
For any elements and in a vector space, the set is called the or closed interval between and The or open interval between and is when while it is when it satisfies and The points and are called the endpoints of these interval. An interval is said to be or proper if its endpoints are distinct.
The intervals and always contain their endpoints while and never contain either of their endpoints.
If and are points in the real line then the above definition of is the same as its usual definition as a closed interval.
For any the point is said to (strictly) and if belongs to the open line segment
If is a subset of and then is called an extreme point of if it does not lie between any two points of That is, if there does exist and such that and In this article, the set of all extreme points of will be denoted by
For example, the vertices of any convex polygon in the plane are the extreme points of that polygon.
The extreme points of the closed unit disk in is the unit circle.
Every open interval and degenerate closed interval in has no extreme points while the extreme points of a non-degenerate closed interval are and
A set is called convex if for any two points contains the line segment The smallest convex set containing is called |
https://en.wikipedia.org/wiki/Predicate%20abstraction | In logic, predicate abstraction is the result of creating a predicate from a formula. If Q is any formula then the predicate abstract formed from that sentence is (λx.Q), where λ is an abstraction operator and in which every occurrence of x that is free in Q is bound by λ in (λx.Q). The resultant predicate (λx.Q(x)) is a monadic predicate capable of taking a term t as argument as in (λx.Q(x))(t), which says that the object denoted by 't' has the property of being such that Q.
The states ( λx.Q(x) )(t) ≡ Q(t/x) where Q(t/x) is the result of replacing all free occurrences of x in Q by t. This law is shown to fail in general in at least two cases: (i) when t is irreferential and (ii) when Q contains modal operators.
In modal logic the "de re / de dicto distinction" is stated as
1. (DE DICTO):
2. (DE RE): .
In (1) the modal operator applies to the formula A(t) and the term t is within the scope of the modal operator. In (2) t is not within the scope of the modal operator. |
https://en.wikipedia.org/wiki/DSL%20filter | A DSL filter (also DSL splitter or microfilter) is an analog low-pass filter installed between analog devices (such as telephones or analog modems) and a plain old telephone service (POTS) line. The DSL filter prevents interference between such devices and a digital subscriber line (DSL) service connected to the same line. Without DSL filters, signals or echoes from analog devices at the top of their frequency range can reduce performance and create connection problems with DSL service, while those from the DSL service at the bottom of its range can cause line noise and other problems for analog devices.
The concept of a low pass filter for ADSL was first described in 1996 by Vic Charlton when working for the Canadian Operations Development Consortium: Low-Pass Filter On All Phones.
DSL filters are passive devices, requiring no power source to operate. Some high-quality filters may contain active transistors to refine the signal.
Components
The primary distinguishing factor between high-quality and low-quality filters is the use of transistors in high-quality (and more expensive) active filters, in addition to the usual components like capacitors, resistors, and ferrite cores, while the low-quality passive filters lack transistors.
Installation
Typical installation for an existing home involves installing DSL filters on every telephone, fax machine, voice band modem, and other voiceband device in the home, leaving the DSL modem as the only unfiltered device. For wall mounted phones, the filter is in the form of a plate hung on the standard wall mount, on which the phone hangs in turn.
In cases where it is possible to run new cables, it can be advantageous to split the telephone line after it enters the home, installing a single DSL filter on one leg and running it to every jack in the home where an analog device will be in use, and dedicating the other (unfiltered) leg to the DSL modem. Some devices such as monitored alarms and Telephone Devices for the Deaf |
https://en.wikipedia.org/wiki/Fekete%20polynomial | In mathematics, a Fekete polynomial is a polynomial
where is the Legendre symbol modulo some integer p > 1.
These polynomials were known in nineteenth-century studies of Dirichlet L-functions, and indeed to Dirichlet himself. They have acquired the name of Michael Fekete, who observed that the absence of real zeroes t of the Fekete polynomial with 0 < t < 1 implies an absence of the same kind for the L-function
This is of considerable potential interest in number theory, in connection with the hypothetical Siegel zero near s = 1. While numerical results for small cases had indicated that there were few such real zeroes, further analysis reveals that this may indeed be a 'small number' effect. |
https://en.wikipedia.org/wiki/Blasteroids | Blasteroids is the third official sequel to the 1979 multidirectional shooter video game, Asteroids. It was developed by Atari Games and released in arcades in 1987. Unlike the previous games, Blasteroids uses raster graphics instead of vector graphics, and has power-ups and a boss.
Home computer ports of Blasteroids were released by Image Works for the Amiga, Amstrad CPC, Atari ST, Commodore 64, MSX, MS-DOS, and ZX Spectrum. An emulated version of Blasteroids is an unlockable mini-game in Lego Dimensions.
Gameplay
The gameplay is basically the same as for the original. The player controls a spaceship viewed from "above" in a 2D representation of space, by rotating the ship, and using thrust to give the ship momentum. To slow down or completely stop moving, the player has to rotate the ship to face the direction it came from, and generate the right amount of thrust to nullify its momentum. The ship has a limited amount of fuel to generate thrust with. This fuel comes in the form of "Energy" that is also used for the ship's Shields which protect it against collisions and enemy fire. Once all Energy is gone, the player's ship is destroyed. The ship can shoot to destroy asteroids and enemy ships. The ship can also be transformed at will into 3 different versions: the Speeder with greatest speed, the Fighter with the most firepower, and the Warrior with extra armor.
Levels
At the start of the game, the player is in a screen with four warps indicating the game's difficulty: Easy, Medium, Hard, and Expert. Flying through any of the warps starts the game with that difficulty. Each has several galaxies, each with 9 or 16 sectors depending on difficulty. Once a sector is completed by destroying all the asteroids, an exit portal appears to lead the player to the galactic map screen. Similarly to the difficulty screen, the player can here choose which Sector to visit next. Completed and empty sectors can be revisited, but this costs energy. Sectors that are currently out |
https://en.wikipedia.org/wiki/List%20of%20coordinate%20charts | This article contains a non-exhaustive list of coordinate charts for Riemannian manifolds and pseudo-Riemannian manifolds. Coordinate charts are mathematical objects of topological manifolds, and they have multiple applications in theoretical and applied mathematics. When a differentiable structure and a metric are defined, greater structure exists, and this allows the definition of constructs such as integration and geodesics.
Charts for Riemannian and pseudo-Riemannian surfaces
The following charts (with appropriate metric tensors) can be used in the stated classes of Riemannian and pseudo-Riemannian surfaces:
Radially symmetric surfaces:
Hyperspherical coordinates
Surfaces embedded in E3:
Monge chart
Certain minimal surfaces:
Asymptotic chart (see also asymptotic line)
Euclidean plane E2:
Cartesian chart
Sphere S2:
Spherical coordinates
Stereographic chart
Central projection chart
Axial projection chart
Mercator chart
Hyperbolic plane H2:
Polar chart
Stereographic chart (Poincaré model)
Upper half-space chart (Poincaré model)
Central projection chart (Klein model)
Mercator chart
AdS2 (or S1,1) and dS2 (or H1,1):
Central projection
Sn
Hopf chart
Hn
Upper half-space chart (Poincaré model)
Hopf chart
The following charts apply specifically to three-dimensional manifolds:
Axially symmetric manifolds:
Cylindrical chart
Parabolic chart
Hyperbolic chart
Toroidal chart
Three-dimensional Euclidean space E3:
Cartesian
Polar spherical chart
Cylindrical chart
Elliptical cylindrical, hyperbolic cylindrical, parabolic cylindrical charts
Parabolic chart
Hyperbolic chart
Prolate spheroidal chart (rational and trigonometric forms)
Oblate spheroidal chart (rational and trigonometric forms)
Toroidal chart
Cassini toroidal chart and Cassini bipolar chart
Three-sphere S3
Polar chart
Stereographic chart
Hopf chart
Hyperbolic three-space H3
Polar chart
Upper half space chart (Poincaré model)
Hopf chart
See also
Coordinate chart
Coordinate system
Metric tensor
List of mathemat |
https://en.wikipedia.org/wiki/Darwinian%20puzzle | A Darwinian puzzle is a trait that appears to reduce the fitness of individuals that possess it. Such traits attract the attention of evolutionary biologists. Several human traits pose challenges to evolutionary thinking, as they are relatively prevalent but are associated with lower reproductive success through reduced fertility and/or longevity. Some of the classic examples include: left handedness, menopause, and mental disorders. These traits are also found in animals, a peacock shows an example of a trait that may reduce its fitness. The bigger the tail, the easier it is seen by predators and it also may hinder the movement of the peacock. Darwin, in fact, solved this "puzzle" by explaining the peacock's tail as evidence of sexual selection; a bigger tail confers evolutionary fitness on the male by allowing it to attract more females than other males with shorter tails. The phrase "Darwinian puzzle" itself is rare and of unclear origin; it's typically talked about in the context of animal behavior.
Applications in nature
Darwinian puzzles are evident in nature, even though it appears to reduce the fitness of the individual that possesses it. Different individuals use the odd phenomenon in particular ways such as toxins, fitness demonstration, and mimicry.
Factors that affect Darwinian puzzles
There are a few contributing factors in biology which may affect Darwinian puzzles.
Coefficient of relatedness (r): the percentage of genes shared by two animals.
This may be based on common descent. Animals may share 1/4, 1/2, or even in some cases all of their genes with others. Identical twins have a coefficient of relatedness of r=1. Full siblings have a coefficient of relatedness of r=.50, and half siblings and first cousins have a coefficient of relatedness of r=.25. Depending on how related two animals are, they may be more likely to act altruistically to one another. Even if it is of no benefit to themselves, it helps to promote survival of at least some of the |
https://en.wikipedia.org/wiki/ACS%20Combinatorial%20Science | ACS Combinatorial Science (usually abbreviated as ACS Comb. Sci.), formerly Journal of Combinatorial Chemistry (1999-2010), was a peer-reviewed scientific journal, published since 1999 by the American Chemical Society. ACS Combinatorial Science publishes articles, reviews, perspectives, accounts and reports in the field of Combinatorial Chemistry.
Anthony Czarnik served as the founding editor from 1999 to 2010. M.G. Finn served as Editor from 2010 to 2020. In 2010, ACS agreed to change the name of the journal to "Combinatorial Science" and it was the first and only ACS journal to be devoted to a way of doing science, rather than to a specific field of knowledge or application.
The journal stopped accepting new submissions in August and the last issue was published in December 2020.
Abstracting and indexing
JCS is currently indexed in:
Chemical Abstracts Service (CAS)
SCOPUS
EBSCOhost
PubMed
Web of Science |
https://en.wikipedia.org/wiki/MAX-3LIN-EQN | MAX-3LIN-EQN is a problem in Computational complexity theory where the input is a system of linear equations (modulo 2). Each equation contains at most 3 variables. The problem is to find an assignment to the variables that satisfies the maximum number of equations.
This problem is closely related to the MAX-3SAT problem. It is NP-hard to approximate MAX-3LIN-EQN with ratio (1/2 - δ) for any δ > 0.
See also
PCP (complexity) |
https://en.wikipedia.org/wiki/MAX-3SAT | MAX-3SAT is a problem in the computational complexity subfield of computer science. It generalises the Boolean satisfiability problem (SAT) which is a decision problem considered in complexity theory. It is defined as:
Given a 3-CNF formula Φ (i.e. with at most 3 variables per clause), find an assignment that satisfies the largest number of clauses.
MAX-3SAT is a canonical complete problem for the complexity class MAXSNP (shown complete in Papadimitriou pg. 314).
Approximability
The decision version of MAX-3SAT is NP-complete. Therefore, a polynomial-time solution can only be achieved if P = NP. An approximation within a factor of 2 can be achieved with this simple algorithm, however:
Output the solution in which most clauses are satisfied, when either all variables = TRUE or all variables = FALSE.
Every clause is satisfied by one of the two solutions, therefore one solution satisfies at least half of the clauses.
The Karloff-Zwick algorithm runs in polynomial-time and satisfies ≥ 7/8 of the clauses. While this algorithm is randomized, it can be derandomized using, e.g., the techniques from to yield a deterministic (polynomial-time) algorithm with the same approximation guarantees.
Theorem 1 (inapproximability)
The PCP theorem implies that there exists an ε > 0 such that (1-ε)-approximation of MAX-3SAT is NP-hard.
Proof:
Any NP-complete problem by the PCP theorem. For x ∈ L, a 3-CNF formula Ψx is constructed so that
x ∈ L ⇒ Ψx is satisfiable
x ∉ L ⇒ no more than (1-ε)m clauses of Ψx are satisfiable.
The Verifier V reads all required bits at once i.e. makes non-adaptive queries. This is valid because the number of queries remains constant.
Let q be the number of queries.
Enumerating all random strings Ri ∈ V, we obtain poly(x) strings since the length of each string .
For each Ri
V chooses q positions i1,...,iq and a Boolean function fR: {0,1}q->{0,1} and accepts if and only if fR(π(i1,...,iq)). Here π refers to the proof obtained from |
https://en.wikipedia.org/wiki/MammaPrint | MammaPrint is a prognostic and predictive diagnostic test for early stage breast cancer patients that assess the risk that a tumor will metastasize to other parts of the body. It gives a binary result, high-risk or low-risk classification, and helps physicians determine whether or not a patient will benefit from chemotherapy. Women with a low risk result can safely forego chemotherapy without decreasing likelihood of disease free survival. MammaPrint is part of the personalized medicine portfolio marketed by Agendia.
MammaPrint is based on the Amsterdam 70-gene breast cancer gene signature and uses formalin-fixed-paraffin-embedded (FFPE) or fresh tissue for microarray analysis. It is a laboratory developed test (LDT) which falls into the class of In Vitro Diagnostic Multivariate Index Assays (IVDMIA). MammaPrint was the first (2007) IVDMIA to be cleared by the Food and Drug Administration (FDA) in a De Novo Classification Process (Evaluation of Automatic Class III Designation) and is the only molecular diagnostic test with a randomized prospective clinical trial validating clinical utility. The test uses RNA isolated from tumor samples and run on custom glass microarray slides in order to determine the expression of a 70-gene signature. The expression profile is then used in a proprietary algorithm to categorically classify the patient as being at either high or low risk of breast cancer recurrence.
MammaPrint has been prospectively, clinically validated for use in early stage (I and II) breast cancer patients regardless of estrogen receptor (ER) or Human Epidermal Growth Factor Receptor 2 (HER2) status, with a tumor size ≤ 5.0 cm, and 0-3 positive lymph nodes (LN0-1), with no special specifications for N1mi pathology. This differentiates MammaPrint from other multi-gene assays in use today that have only shown predictive value in ER positive, HER2 negative, lymph node (LN) negative patients. MammaPrint is also indicated for patients with ER negative tumors (15% |
https://en.wikipedia.org/wiki/Abraham%E2%80%93Lorentz%20force | In the physics of electromagnetism, the Abraham–Lorentz force (also known as the Lorentz–Abraham force) is the recoil force (a force of equal magnitude and opposite direction) on an accelerating charged particle caused by the particle emitting electromagnetic radiation by self-interaction. It is also called the radiation reaction force, the radiation damping force, or the self-force. It is named after the physicists Max Abraham and Hendrik Lorentz.
The formula although predating the theory of special relativity, was initially calculated for non-relativistic velocity approximations was extended to arbitrary velocities by Max Abraham and was shown to be physically consistent by George Adolphus Schott. The non-relativistic form is called Lorentz self-force while the relativistic version is called the Lorentz–Dirac force or collectively known as Abraham–Lorentz–Dirac force. The equations are in the domain of classical physics, not quantum physics, and therefore may not be valid at distances of roughly the Compton wavelength or below. There are, however, two analogs of the formula that are both fully quantum and relativistic: one is called the "Abraham–Lorentz–Dirac–Langevin equation", the other is the self-force on a moving mirror.
The force is proportional to the square of the object's charge, multiplied by the jerk that it is experiencing. (Jerk is the rate of change of acceleration.) The force points in the direction of the jerk. For example, in a cyclotron, where the jerk points opposite to the velocity, the radiation reaction is directed opposite to the velocity of the particle, providing a braking action. The Abraham–Lorentz force is the source of the radiation resistance of a radio antenna radiating radio waves.
There are pathological solutions of the Abraham–Lorentz–Dirac equation in which a particle accelerates in advance of the application of a force, so-called pre-acceleration solutions. Since this would represent an effect occurring before its cause |
https://en.wikipedia.org/wiki/List%20of%20social%20software | This is a list of notable social software: selected examples of social software products and services that facilitate a variety of forms of social human contact.
Blogs
Apache Roller
Blogger
IBM Lotus Connections
Posterous
Telligent Community
Tumblr
Typepad
WordPress
Xanga
Clipping
Diigo
Evernote
Instant messaging
Comparison of instant messaging clients
IBM Lotus Sametime
Live Communications Server 2003
Live Communications Server 2005
Microsoft Lync Server
Internet forums
Comparison of Internet forum software
Internet Relay Chat (IRC)
Internet Relay Chat
eLearning
Massively multiplayer online games
Media sharing
blip.tv
Dailymotion
Flickr
Ipernity
Metacafe
Putfile
SmugMug
Tangle
Vimeo
YouTube
Zooomr
IBM Lotus Connections
Media cataloging
Online dating
Web directories
Social bookmarking
Web widgets
AddThis
AddToAny
ShareThis
Social bookmark link generator
Websites
Enterprise software
Altova MetaTeam
IBM Lotus Connections
Jumper 2.0 Enterprise
Social cataloging
aNobii
Goodreads
Knowledge Plaza
Librarything
Readgeek
Shelfari
KartMe
Social citations
BibSonomy
CiteULike
Connotea
Jumper 2.0 Enterprise
Knowledge Plaza
Mendeley
refbase
Zotero
Social evolutionary computation
Knowledge iN
Quora
Yahoo! Answers
Social login
Social networks
Social search
Jumper 2.0
Knowledge Plaza
Social customer support software
Virtual worlds
Active Worlds
Google Lively (now defunct)
Kaneva
Second Life
There
Meez
Wikis |
https://en.wikipedia.org/wiki/Citation%20impact | Citation impact or citation rate is a measure of how many times an academic journal article or book or author is cited by other articles, books or authors.
Citation counts are interpreted as measures of the impact or influence of academic work and have given rise to the field of bibliometrics or scientometrics, specializing in the study of patterns of academic impact through citation analysis. The importance of journals can be measured by the average citation rate,
the ratio of number of citations to number articles published within a given time period and in a given index, such as the journal impact factor or the citescore. It is used by academic institutions in decisions about academic tenure, promotion and hiring, and hence also used by authors in deciding which journal to publish in. Citation-like measures are also used in other fields that do ranking, such as Google's PageRank algorithm, software metrics, college and university rankings, and business performance indicators.
Article-level
One of the most basic citation metrics is how often an article was cited in other articles, books, or other sources (such as theses). Citation rates are heavily dependent on the discipline and the number of people working in that area. For instance, many more scientists work in neuroscience than in mathematics, and neuroscientists publish more papers than mathematicians, hence neuroscience papers are much more often cited than papers in mathematics. Similarly, review papers are more often cited than regular research papers because they summarize results from many papers. This may also be the reason why papers with shorter titles get more citations, given that they are usually covering a broader area.
Most-cited papers
The most-cited paper in history is a paper by Oliver Lowry describing an assay to measure the concentration of proteins. By 2014 it had accumulated more than 305,000 citations. The 10 most cited papers all had more than 40,000 citations. To reach the top-100 p |
https://en.wikipedia.org/wiki/Juice%20%28aggregator%29 | Juice is a podcast aggregator for Windows and OS X used for downloading media files such as ogg and mp3 for playback on the computer or for copying to a digital audio player. Juice lets a user schedule downloading of specific podcasts, and will notify the user when a new show is available. It is free software available under the GNU General Public License. The project is hosted at SourceForge. Formerly known as iPodder and later as iPodder Lemon, the software's name was changed to Juice in November 2005 in the face of legal pressure from Apple, Inc.
Development
The original development team was formed by Erik de Jonge, Robin Jans, Martijn Venrooy, Perica Zivkovic from the company Active8 based in the Netherlands, Andrew Grumet, Garth Kidd and Mark Posth joined the team soon after the first release. The development team credited the program concept to Adam Curry who wrote a little Applescript as a proof of concept and provided the first podcast shows (then referred to as 'audio enclosures') but primarily to Dave Winer who was the inspiration for Adam Curry. The first version also included a screenscraper for normal HTML files. Initially it was not clear that podcasting would be completely tied to RSS. Although that was eventually the method chosen, during the early development phase a diverse range of people were working on alternatives, including a version based on Freenet.
The program is written in Python and, through use of a cross-platform UI library, runs on Mac OS X and Microsoft Windows 2000 or Windows XP. A Linux variant has not been developed.
The 2004 growth of podcasting inspired other podcatching programs, such as jPodder, as well as the June 2005 addition of a podcast subscription feature in Apple's iTunes music player. This development quickly put an end to the popularity of the Juice application.
In 2006 the team effectively stopped further development of the program, the developers started working in other fields, some Podcasting related. The tea |
https://en.wikipedia.org/wiki/Oldest%20Dryas | The Oldest Dryas is a biostratigraphic subdivision layer corresponding to a relatively abrupt climatic cooling event, or stadial, which occurred during the last glacial retreat. The time period to which the layer corresponds is poorly defined and varies between regions, but it is generally dated as starting at 18.5–17 thousand years (ka) before present (BP) and ending 15–14 ka BP. As with the Younger and Older Dryas events, the stratigraphic layer is marked by abundance of the pollen and other remains of Dryas octopetala, an indicator species that colonizes arctic-alpine regions. The termination of the Oldest Dryas is marked by an abrupt oxygen isotope excursion, which has been observed at many sites in the Alps that correspond to this interval of time.
In the Alps, the Oldest Dryas corresponds to the Gschnitz stadial of the Würm glaciation. The term was originally defined specifically for terrestrial records in the region of Scandinavia, but has come to be used both for ice core stratigraphy in areas across the world, and to refer to the time period itself and its associated temporary reversal of the glacial retreat.
In the Iberian Peninsula, the glaciers of the Pyrenees, Sierra Nevada, Central Range, and Northwestern Mountains, which had almost entirely disappeared by 17,500 BP, began to advance once again. Between 16,800 and 16,500 BP, these glaciers abruptly advanced into montane valleys and deposited moraines near the moraines formed during the Last Glacial Maximum. These glaciers then began to oscillate between advance and retreat until a final glacial advance at 15,500 BP. A thousand years later, following a general glacial retreat, these alpine glaciers were relegated to cirques.
Flora
During the Oldest Dryas, Europe was treeless and similar to the Arctic tundra, but much drier and grassier than the modern tundra. It contained shrubs and herbaceous plants such as the following:
Poaceae, grasses
Artemisia
Betula nana, dwarf birch
Salix retusa, dwarf willo |
https://en.wikipedia.org/wiki/Outline%20of%20biochemistry | The following outline is provided as an overview of and topical guide to biochemistry:
Biochemistry – study of chemical processes in living organisms, including living matter. Biochemistry governs all living organisms and living processes.
Applications of biochemistry
Testing
Ames test – salmonella bacteria is exposed to a chemical under question (a food additive, for example), and changes in the way the bacteria grows are measured. This test is useful for screening chemicals to see if they mutate the structure of DNA and by extension identifying their potential to cause cancer in humans.
Pregnancy test – one uses a urine sample and the other a blood sample. Both detect the presence of the hormone human chorionic gonadotropin (hCG). This hormone is produced by the placenta shortly after implantation of the embryo into the uterine walls and accumulates.
Breast cancer screening – identification of risk by testing for mutations in two genes—Breast Cancer-1 gene (BRCA1) and the Breast Cancer-2 gene (BRCA2)—allow a woman to schedule increased screening tests at a more frequent rate than the general population.
Prenatal genetic testing – testing the fetus for potential genetic defects, to detect chromosomal abnormalities such as Down syndrome or birth defects such as spina bifida.
PKU test – Phenylketonuria (PKU) is a metabolic disorder in which the individual is missing an enzyme called phenylalanine hydroxylase. Absence of this enzyme allows the buildup of phenylalanine, which can lead to mental retardation.
Genetic engineering – taking a gene from one organism and placing it into another. Biochemists inserted the gene for human insulin into bacteria. The bacteria, through the process of translation, create human insulin.
Cloning – Dolly the sheep was the first mammal ever cloned from adult animal cells. The cloned sheep was, of course, genetically identical to the original adult sheep. This clone was created by taking cells from the udder of a six-year-old |
https://en.wikipedia.org/wiki/Anthrozoology | Anthrozoology, also known as human–nonhuman-animal studies (HAS), is the subset of ethnobiology that deals with interactions between humans and other animals. It is an interdisciplinary field that overlaps with other disciplines including anthropology, ethnology, medicine, psychology, social work, veterinary medicine, and zoology. A major focus of anthrozoologic research is the quantifying of the positive effects of human–animal relationships on either party and the study of their interactions. It includes scholars from fields such as anthropology, sociology, biology, history and philosophy.
Anthrozoology scholars, such as Pauleen Bennett recognize the lack of scholarly attention given to non-human animals in the past, and to the relationships between human and non-human animals, especially in the light of the magnitude of animal representations, symbols, stories and their actual physical presence in human societies. Rather than a unified approach, the field currently consists of several methods adapted from the several participating disciplines to encompass human–nonhuman animal relationships and occasional efforts to develop sui generis methods.
Areas of study
The interaction and enhancement within captive animal interactions.
Affective (emotional) or relational bonds between humans and animals
Human perceptions and beliefs in respect of other animals
How some animals fit into human societies
How these vary between cultures, and change over times
The study of animal domestication: how and why domestic animals evolved from wild species (paleoanthrozoology)
Captive zoo animal bonds with keepers
The social construction of animals and what it means to be animal
The human–animal bond
Parallels between human–animal interactions and human–technology interactions
The symbolism of animals in literature and art
The history of animal domestication
The intersections of speciesism, racism, and sexism
The place of animals in human-occupied spaces
The religious |
https://en.wikipedia.org/wiki/Horticultural%20oil | Horticultural oils or narrow range oils are lightweight oils, either petroleum or vegetable based. They are used in both horticulture and agriculture, where they are applied as a dilute spray on plant surfaces to control insects and mites. They are also sometimes included in tank mixes as a surfactant.
The oils provide control by smothering the target pests, and are only effective if applied directly to the pest, and provide no residual controls.
Oils are generally considered suitable for "organic pest control", with most oils permitted under the U.S. National Organic Program.
Types of oils
Dormant oil: An oil used on woody plants during the dormant season. This term originally referred to heavier weight, less well-refined oils that were unsafe to use on plants after they broke dormancy. However, these older oils have been replaced with more refined, light-weight oils that have potential application to plant foliage. Dormant oil now refers to the time of application rather than to any characteristic type of oil.
Horticultural oils: An oil used to control a pest on plants.
Mineral oil: A petroleum-derived oil (as opposed to vegetable oils).
Narrow-range oil: A highly refined oil that has a narrow range of distillation. Narrow-range oils fall in the superior oil classification. The terms may be used nearly interchangeably.
Spray oil: An oil designed to be mixed with water and applied to plants as a spray for pest control.
Summer oil: An oil used on plants when foliage is present (also called foliar oils). As with dormant oil, the term now refers to the time an application is made rather than to the properties of the oil.
Supreme oil: A term used to categorize highly refined oils that distill at slightly higher temperatures and over a wider range than the narrow-range oils. Most supreme oils meet the characteristics of a superior oil.
Superior oil: A term originated by P.J. Chapman in 1947 to categorize summer-use oils that met certain specifications. This in |
https://en.wikipedia.org/wiki/Dmitri%20Egorov | Dmitri Fyodorovich Egorov (; December 22, 1869 – September 10, 1931) was a Russian and Soviet mathematician known for contributions to the areas of differential geometry and mathematical analysis. He was President of the Moscow Mathematical Society (1923–1930).
Life
Egorov held spiritual beliefs to be of great importance, and openly defended the Church against Marxist supporters after the Russian Revolution. He was elected president of the Moscow Mathematical Society in 1921, and became director of the Institute for Mechanics and Mathematics at Moscow State University in 1923. He also edited the journal Matematicheskii Sbornik of the Moscow Mathematical Society. However, because of Egorov's stance against the repression of the Russian Orthodox Church, he was dismissed from the Institute in 1929 and publicly rebuked. In 1930 he was arrested and imprisoned as a "religious sectarian", and soon after was expelled from the Moscow Mathematical Society. Upon imprisonment, Egorov began a hunger strike until he was taken to the prison hospital, and eventually to the house of fellow mathematician Nikolai Chebotaryov where he died. He was buried in Arskoe Cemetery in Kazan.
Research work
Egorov studied potential surfaces and triply orthogonal systems, and made contributions to the broader areas of differential geometry and integral equations. His work was influenced by that of Jean Gaston Darboux on differential geometry and by Henri Lebesgue in mathematical analysis. A theorem in real analysis and integration theory, Egorov's Theorem, is named after him.
Works
, available at Gallica.
Notes
Bibliography
.
.
External links
Mathematicians from the Russian Empire
Differential geometers
Academic staff of Moscow State University
Corresponding Members of the Russian Academy of Sciences (1917–1925)
Corresponding Members of the USSR Academy of Sciences
Honorary Members of the USSR Academy of Sciences
Mathematicians from Moscow
Egorov, Dmitri
1869 births
1931 deaths
Professor |
https://en.wikipedia.org/wiki/Beam%20stack%20search | Beam stack search is a search algorithm that combines chronological backtracking (that is, depth-first search) with beam search and is similar to depth-first beam search. Both search algorithms are anytime algorithms that find good but likely sub-optimal solutions quickly, like beam search, then backtrack and continue to find improved solutions until convergence to an optimal solution.
Implementation
Beam stack search uses the beam stack as a data structure to integrate chronological backtracking with beam search and can be combined with the divide and conquer algorithm technique, resulting in divide-and-conquer beam-stack search.
Alternatives
Beam search using limited discrepancy backtracking (BULB) is a search algorithm that combines limited discrepancy search with beam search and thus performs non-chronological backtracking, which often outperforms the chronological backtracking done by beam stack search and depth-first beam search. |
https://en.wikipedia.org/wiki/David%20Ruelle | David Pierre Ruelle (; born 20 August 1935) is a Belgian mathematical physicist, naturalized French. He has worked on statistical physics and dynamical systems. With Floris Takens, Ruelle coined the term strange attractor, and developed a new theory of turbulence.
Biography
Ruelle studied physics at the Université Libre de Bruxelles, obtaining a PhD degree in 1959 under the supervision of Res Jost. He spent two years (1960–1962) at the ETH Zurich, and another two years (1962–1964) at the Institute for Advanced Study in Princeton, New Jersey. In 1964, he became professor at the Institut des Hautes Études Scientifiques in Bures-sur-Yvette, France. Since 2000, he has been an emeritus professor at IHES and distinguished visiting professor at Rutgers University.
David Ruelle made fundamental contributions in various aspects of mathematical physics. In quantum field theory, the most important contribution is the rigorous formulation of scattering processes based on Wightman's axiomatic theory. This approach is known as the Haag–Ruelle scattering theory. Later Ruelle helped to create a rigorous theory of statistical mechanics of equilibrium, that includes the study of the thermodynamic limit, the equivalence of ensembles, and the convergence of Mayer's series. A further result is the Asano-Ruelle lemma, which allows the study of the zeros of certain polynomial functions that are recurrent in statistical mechanics.
The study of infinite systems led to the local definition of Gibbs states or to the global definition of equilibrium states. Ruelle demonstrated with Roland L. Dobrushin and Oscar E. Lanford that translationally invariant Gibbs states are precisely the equilibrium states.
Together with Floris Takens, he proposed the description of hydrodynamic turbulence based on strange attractors with chaotic properties of hyperbolic dynamics.
Honors and awards
Since 1985 David Ruelle has been a member of the French Academy of Sciences and in 1988 he was Josiah Willard G |
https://en.wikipedia.org/wiki/LwIP | lwIP (lightweight IP) is a widely used open-source TCP/IP stack designed for embedded systems. lwIP was originally developed by Adam Dunkels at the Swedish Institute of Computer Science and is now developed and maintained by a worldwide network of developers.
lwIP is used by many manufacturers of embedded systems, including Intel/Altera, Analog Devices, Xilinx, TI, ST and Freescale.
lwIP network stack
The focus of the lwIP network stack implementation is to reduce resource usage while still having a full-scale TCP stack. This makes lwIP suitable for use in embedded systems with tens of kilobytes of free RAM and room for around 40 kilobytes of code ROM.
lwIP protocol implementations
Aside from the TCP/IP stack, lwIP has several other important parts, such as a network interface, an operating system emulation layer, buffers and a memory management section. The operating system emulation layer and the network interface allow the network stack to be transplanted into an operating system, as it provides a common interface between lwIP code and the operating system kernel.
The network stack of lwIP includes an IP (Internet Protocol) implementation at the Internet layer that can handle packet forwarding over multiple network interfaces. Both IPv4 and IPv6 are supported dual stack since lwIP v2.0.0 . For network maintenance and debugging, lwIP implements ICMP (Internet Control Message Protocol). IGMP (Internet Group Management Protocol) is supported for multicast traffic management. While ICMPv6 (including MLD) is implemented to support the use of IPv6.
lwIP includes an implementation of IPv4 ARP (Address Resolution Protocol) and IPv6 Neighbor Discovery Protocol to support Ethernet at the data link layer. lwIP may also be operated on top of a PPP (Point-to-Point Protocol) implementation at the data link layer.
At the transport layer lwIP implements TCP (Transmission Control Protocol) with congestion control, RTT estimation and fast recovery/fast retransmit. UDP (U |
https://en.wikipedia.org/wiki/Screening%20%28medicine%29 | Screening, in medicine, is a strategy used to look for as-yet-unrecognised conditions or risk markers. This testing can be applied to individuals or to a whole population. The people tested may not exhibit any signs or symptoms of a disease, or they might exhibit only one or two symptoms, which by themselves do not indicate a definitive diagnosis.
Screening interventions are designed to identify conditions which could at some future point turn into disease, thus enabling earlier intervention and management in the hope to reduce mortality and suffering from a disease. Although screening may lead to an earlier diagnosis, not all screening tests have been shown to benefit the person being screened; overdiagnosis, misdiagnosis, and creating a false sense of security are some potential adverse effects of screening. Additionally, some screening tests can be inappropriately overused. For these reasons, a test used in a screening program, especially for a disease with low incidence, must have good sensitivity in addition to acceptable specificity.
Several types of screening exist: universal screening involves screening of all individuals in a certain category (for example, all children of a certain age). Case finding involves screening a smaller group of people based on the presence of risk factors (for example, because a family member has been diagnosed with a hereditary disease). Screening interventions are not designed to be diagnostic, and often have significant rates of both false positive and false negative results.
Frequently updated recommendations for screening are provided by the independent panel of experts, the United States Preventive Services Task Force.
Principles
In 1968, the World Health Organization published guidelines on the Principles and practice of screening for disease, which often referred to as Wilson and Jungner criteria. The principles are still broadly applicable today:
The condition should be an important health problem.
There should be |
https://en.wikipedia.org/wiki/Local%20cohomology | In algebraic geometry, local cohomology is an algebraic analogue of relative cohomology. Alexander Grothendieck introduced it in seminars in Harvard in 1961 written up by , and in 1961-2 at IHES written up as SGA2 - , republished as . Given a function (more generally, a section of a quasicoherent sheaf) defined on an open subset of an algebraic variety (or scheme), local cohomology measures the obstruction to extending that function to a larger domain. The rational function , for example, is defined only on the complement of on the affine line over a field , and cannot be extended to a function on the entire space. The local cohomology module (where is the coordinate ring of ) detects this in the nonvanishing of a cohomology class . In a similar manner, is defined away from the and axes in the affine plane, but cannot be extended to either the complement of the -axis or the complement of the -axis alone (nor can it be expressed as a sum of such functions); this obstruction corresponds precisely to a nonzero class in the local cohomology module .
Outside of algebraic geometry, local cohomology has found applications in commutative algebra, combinatorics, and certain kinds of partial differential equations.
Definition
In the most general geometric form of the theory, sections are considered of a sheaf of abelian groups, on a topological space , with support in a closed subset , The derived functors of form local cohomology groups
In the theory's algebraic form, the space X is the spectrum Spec(R) of a commutative ring R (assumed to be Noetherian throughout this article) and the sheaf F is the quasicoherent sheaf associated to an R-module M, denoted by . The closed subscheme Y is defined by an ideal I. In this situation, the functor ΓY(F) corresponds to the I-torsion functor, a union of annihilators
i.e., the elements of M which are annihilated by some power of I. As a right derived functor, the ith local cohomology module with respect to I is the ith c |
https://en.wikipedia.org/wiki/Cuminaldehyde | Cuminaldehyde (4-isopropylbenzaldehyde) is a natural organic compound with the molecular formula C10H12O. It is a benzaldehyde with an isopropyl group substituted in the 4-position.
Cuminaldehyde is a constituent of the essential oils of eucalyptus, myrrh, cassia, cumin, and others. It has a pleasant smell and contributes to the aroma of these oils. It is used commercially in perfumes and other cosmetics.
It has been shown that cuminaldehyde, as a small molecule, inhibits the fibrillation of alpha-synuclein, which, if aggregated, forms insoluble fibrils in pathological conditions characterized by Lewy bodies, such as Parkinson's disease, dementia with Lewy bodies and multiple system atrophy.
Cuminaldehyde can be prepared synthetically by the reduction of 4-isopropylbenzoyl chloride or by the formylation of cumene.
The thiosemicarbazone of cuminaldehyde has antiviral properties. |
https://en.wikipedia.org/wiki/Solaris%20Multiplexed%20I/O | Solaris Multiplexed I/O (MPxIO), known also as Sun StorageTek Traffic Manager (SSTM, earlier Sun StorEdge Traffic Manager), is multipath I/O software for Solaris/illumos. It enables a storage device to be accessed through multiple host controller interfaces from a single operating system instance. The MPxIO architecture helps protect against I/O outages due to I/O controller failures. Should one I/O controller fail, MPxIO automatically switches to an alternate controller.
This architecture also increases I/O performance by load balancing across multiple I/O channels.
It was integrated within the Solaris operating system beginning in February 2000 with Solaris 8 release.
The file to enable or disable mpxio has been moved in Solaris 10 from /kernel/drv/scsi_vhci.conf to the bottom of the file /kernel/drv/fp.conf and /kernel/drv/mpt.conf.
See also
Multipath I/O |
https://en.wikipedia.org/wiki/Guaiacol | Guaiacol () is an organic compound with the formula C6H4(OH)(OCH3). It is a phenolic compound containing a methoxy functional group. Guaiacol appears as a viscous colorless oil, although aged or impure samples are often yellowish. It occurs widely in nature and is a common product of the pyrolysis of wood.
Occurrence
Guaiacol is usually derived from guaiacum or wood creosote.
It is produced by a variety of plants. It is also found in essential oils from celery seeds, tobacco leaves, orange leaves, and lemon peels. The pure substance is colorless, but samples become yellow upon exposure to air and light. The compound is present in wood smoke, resulting from the pyrolysis of lignin. The compound contributes to the flavor of many substances such as whiskey and roasted coffee.
Preparation
The compound was first isolated by Otto Unverdorben in 1826. Guaiacol is produced by methylation of o-catechol, for example using potash and dimethyl sulfate:
C6H4(OH)2 + (CH3O)2SO2 → C6H4(OH)(OCH3) + HO(CH3O)SO2
Laboratory methods
Guaiacol can be prepared by diverse routes in the laboratory. o-Anisidine, derived in two steps from anisole, can be hydrolyzed via its diazonium derivative. Guaiacol can be synthesized by the dimethylation of catechol followed by selective mono-demethylation.
C6H4(OCH3)2 + C2H5SNa → C6H4(OCH3)(ONa) + C2H5SCH3
Uses and chemical reactions
Syringyl/guaiacyl ratio
Lignin, comprising a major fraction of biomass, is sometimes classified according to the guaiacyl component. Pyrolysis of lignin from gymnosperms gives more guaiacol, resulting from removal of the propenyl group of coniferyl alcohol. These lignins are said to have a high guaiacyl (or G) content. In contrast, lignins derived from sinapyl alcohol affords syringol. A high syringyl (or S) content is indicative of lignin from angiosperms. Sugarcane bagasse is one useful source of guaiacol; pyrolysis of the bagasse lignins yields compounds including guaiacol, 4-methylguaiacol and |
https://en.wikipedia.org/wiki/Permanent%20teeth | Permanent teeth or adult teeth are the second set of teeth formed in diphyodont mammals. In humans and old world simians, there are thirty-two permanent teeth, consisting of six maxillary and six mandibular molars, four maxillary and four mandibular premolars, two maxillary and two mandibular canines, four maxillary and four mandibular incisors.
Timeline
The first permanent tooth usually appears in the mouth at around 5-6 years of age, and the mouth will then be in a transition time with both primary (or deciduous dentition) teeth and permanent teeth during the mixed dentition period until the last primary tooth is lost or shed.
The first of the permanent teeth to erupt are the permanent first molars, right behind the last 'milk' molars of the primary dentition. These first permanent molars are important for the correct development of a permanent dentition. Up to thirteen years of age, 28 of the 32 permanent teeth will appear.
The full permanent dentition is completed much later during the permanent dentition period. The four last permanent teeth, the third molars, usually appear between the ages of 17 and 38 years; they are considered wisdom teeth.
Pathology
It is possible to have extra, or "supernumerary", teeth. This phenomenon is called hyperdontia and is often erroneously referred to as "a third set of teeth." These teeth may erupt into the mouth or remain impacted in the bone. Hyperdontia is often associated with syndromes such as cleft lip and cleft palate, tricho-rhino-phalangeal syndrome, cleidocranial dysplasia, and Gardner's syndrome.
See also
Deciduous dentition
Tooth development
Tooth eruption
Teething
Dentition |
https://en.wikipedia.org/wiki/Internet%20Listing%20Display | Internet Listing Display (ILD) was a set of rules put forth by the National Association of National Association of Realtors in 2005 to regulate how homes and properties can be displayed on internet sites. The ILD policy was intended to consolidate and replace both the Virtual Office Website (VOW) and Internet Data Exchange (IDX) policies to create one set of rules.
The ILD policy is a work in progress created as a result of investigation from the U.S. Department of Justice into anti-competitive practices by traditional real estate brokers. The ILD policy is intended to prevent traditional brokers from solely excluding their property listings from selected discount broker web sites, since they must "opt out" from display on all other brokers' sites
.
In late 2005, the NAR recommended to avoid using ILD, and the policy has since largely been abandoned.
See also
Internet Data Exchange (IDX)
Real estate trends
Virtual Office Website (VOW) |
https://en.wikipedia.org/wiki/Schwarz%20reflection%20principle | In mathematics, the Schwarz reflection principle is a way to extend the domain of definition of a complex analytic function, i.e., it is a form of analytic continuation. It states that if an analytic function is defined on the upper half-plane, and has well-defined (non-singular) real values on the real axis, then it can be extended to the conjugate function on the lower half-plane. In notation, if is a function that satisfies the above requirements, then its extension to the rest of the complex plane is given by the formula,
That is, we make the definition that agrees along the real axis.
The result proved by Hermann Schwarz is as follows. Suppose that F is a continuous function on the closed upper half plane , holomorphic on the upper half plane , which takes real values on the real axis. Then the extension formula given above is an analytic continuation to the whole complex plane.
In practice it would be better to have a theorem that allows F certain singularities, for example F a meromorphic function. To understand such extensions, one needs a proof method that can be weakened. In fact Morera's theorem is well adapted to proving such statements. Contour integrals involving the extension of F clearly split into two, using part of the real axis. So, given that the principle is rather easy to prove in the special case from Morera's theorem, understanding the proof is enough to generate other results.
The principle also adapts to apply to harmonic functions.
See also
Kelvin transform
Method of image charges
Schwarz function |
https://en.wikipedia.org/wiki/Electronic%20hardware | Electronic hardware consists of interconnected electronic components which perform analog or logic operations on received and locally stored information to produce as output or store resulting new information or to provide control for output actuator mechanisms.
Electronic hardware can range from individual chips/circuits to distributed information processing systems. Well designed electronic hardware is composed of hierarchies of functional modules which inter-communicate via precisely defined interfaces.
Hardware logic is primarily a differentiation of the data processing circuitry from other more generalized circuitry. For example nearly all computers include a power supply which consists of circuitry not involved in data processing but rather powering the data processing circuits. Similarly, a computer may output information to a computer monitor or audio amplifier which is also not involved in the computational processes.
See also
Digital electronics |
https://en.wikipedia.org/wiki/Euler%E2%80%93Fokker%20genus | In music theory and tuning, an Euler–Fokker genus (plural: genera), named after Leonhard Euler and Adriaan Fokker, is a musical scale in just intonation whose pitches can be expressed as products of some of the members of some multiset of generating prime factors. Powers of two are usually ignored, because of the way the human ear perceives octaves as equivalent.
An x-dimensional tone-dimension contains x factors. "An Euler-Fokker genus with two dimensions may be represented in a two-dimensional (rectangular) tone-grid, one with three dimensions in a three-dimensional (block-shaped) tone-lattice. Euler-Fokker genera are characterized by a listing of the number of steps in each dimension. The number of steps is represented by a repeated mention of the dimension, so that there arise descriptions such as [3 3 5 5], [3 5 7], [3 3 5 5 7 7 11 11], etc." For example, the multiset {3, 3, 7} yields the Euler–Fokker genus [3, 3, 7], which contains these pitches:
1
3 =3
7=7
3×3 =9
3×7=21
3×3×7=63
Normalized to fall within an octave, these become: 1/1, 9/8, 21/16, 3/2, 7/4, 63/32.
Euler genera are generated from the prime factors 3 and 5, whereas an Euler–Fokker genus can have factors of 7 or any higher prime number. The degree is the number of intervals which generate a genus. However, not all genera of the same degree have the same number of tones since [XXXYYY] may also be notated [XxYy], "the degree is thus the sum of the exponents," and the number of pitches is obtained adding one to each exponent and then multiplying those ((X+1)×(Y+1)=Z).
Adriaan Fokker wrote much of his music in Euler–Fokker genera expressed in 31-tone equal temperament. Alan Ridout also used Euler-Fokker genera.
Complete contracted chord
The Euler–Fokker genus may also be called a complete contracted chord. Euler coined the term complete chord, while Fokker coined the entire term.
A complete chord has two pitches, the fundamental and a guide tone, the guide tone bein |
https://en.wikipedia.org/wiki/Mean%20value%20theorem%20%28divided%20differences%29 | In mathematical analysis, the mean value theorem for divided differences generalizes the mean value theorem to higher derivatives.
Statement of the theorem
For any n + 1 pairwise distinct points x0, ..., xn in the domain of an n-times differentiable function f there exists an interior point
where the nth derivative of f equals n ! times the nth divided difference at these points:
For n = 1, that is two function points, one obtains the simple mean value theorem.
Proof
Let be the Lagrange interpolation polynomial for f at x0, ..., xn.
Then it follows from the Newton form of that the highest term of is .
Let be the remainder of the interpolation, defined by . Then has zeros: x0, ..., xn.
By applying Rolle's theorem first to , then to , and so on until , we find that has a zero . This means that
,
Applications
The theorem can be used to generalise the Stolarsky mean to more than two variables. |
https://en.wikipedia.org/wiki/B%C3%B4cher%27s%20theorem | In mathematics, Bôcher's theorem is either of two theorems named after the American mathematician Maxime Bôcher.
Bôcher's theorem in complex analysis
In complex analysis, the theorem states that the finite zeros of the derivative of a non-constant rational function that are not multiple zeros are also the positions of equilibrium in the field of force due to particles of positive mass at the zeros of and particles of negative mass at the poles of , with masses numerically equal to the respective multiplicities, where each particle repels with a force equal to the mass times the inverse distance.
Furthermore, if C1 and C2 are two disjoint circular
regions which contain respectively all the zeros and all the poles of , then C1 and C2 also contain all the critical
points of .
Bôcher's theorem for harmonic functions
In the theory of harmonic functions, Bôcher's theorem states that a positive harmonic function in a punctured domain (an open domain minus one point in the interior) is a linear combination of a harmonic function in the unpunctured domain with a scaled fundamental solution for the Laplacian in that domain.
See also
Marden's theorem
External links
(Review of Joseph L. Walsh's book.)
Theorems in complex analysis
Harmonic functions |
https://en.wikipedia.org/wiki/Menthone | Menthone is a monoterpene with a minty flavor that occurs naturally in a number of essential oils. l-Menthone (or (2S,5R)-trans-2-isopropyl-5-methylcyclohexanone), shown at right, is the most abundant in nature of the four possible stereoisomers. It is structurally related to menthol, which has a secondary alcohol in place of the carbonyl. Menthone is used in flavoring, perfume and cosmetics for its characteristic aromatic and minty odor.
Occurrence
Menthone is a constituent of the essential oils of pennyroyal, peppermint, Mentha arvensis, Pelargonium geraniums, and others. In most essential oils, it is a minor compound; it was first synthesized by oxidation of menthol in 1881 before it was found in essential oils in 1891.
Structure and preparation
2-Isopropyl-5-methylcyclohexanone has two asymmetric carbon centers, meaning that it can have four different stereoisomers: (2S,5S), (2R,5S), (2S,5R) and (2R,5R). The S,S and R,R stereoisomers have the methyl and isopropyl groups on the same side of the cyclohexane ring: the so-called cis conformation. These stereoisomers are called isomenthone. The trans-isomers are called menthone. Because the (2S,5R) isomer has negative optical rotation, it is called l-menthone or (−)-menthone. It is the enantiomeric partner of the (2R,5S) isomer: (+)- or d-menthone. Menthone can easily be converted to isomenthone and vice versa via a reversible epimerization reaction via an enol intermediate, which changes the direction of optical rotation, so that l-menthone becomes d-isomenthone, and d-menthone becomes l-isomenthone.
In the laboratory, l-menthone may be prepared by oxidation of menthol with acidified dichromate. If the chromic acid oxidation is performed with stoichiometric oxidant in the presence of diethyl ether as co-solvent, a method introduced by H.C. Brown, the epimerization of l-menthone to d-isomenthone is largely avoided. If menthone and isomenthone are equilibrated at room temperature, the isomenthone content will re |
https://en.wikipedia.org/wiki/Moisture%20vapor%20transmission%20rate | Moisture vapor transmission rate (MVTR), also water vapor transmission rate (WVTR), is a measure of the passage of water vapor through a substance. It is a measure of the permeability for vapor barriers.
There are many industries where moisture control is critical. Moisture sensitive foods and pharmaceuticals are put in packaging with controlled MVTR to achieve the required quality, safety, and shelf life. In clothing, MVTR as a measure of breathability has contributed to greater comfort for wearers of clothing for outdoor activity. The building materials industry also manages the moisture barrier properties in architectural components to ensure the correct moisture levels in the internal spaces of buildings. Optoelectronic devices based on organic material, generally named OLEDs, need an encapsulation with low values of WVTR to guarantee the same performances over the lifetime of the device.
MVTR generally decreases with increasing thickness of the film/barrier, and increases with increasing temperature.
Measurement
There are various techniques to measure MVTR, ranging from gravimetric techniques that measure the gain or loss of moisture by mass, to highly sophisticated instrumental techniques that in some designs can measure extremely low transmission rates. Special care has to be taken in measuring porous substances such as fabrics, as some techniques are not appropriate. For very low levels, many techniques do not have adequate resolution. Numerous standard methods are described in ISO, ASTM, BS, DIN etc.—these are quite often industry-specific. Instrument manufacturers are often able to provide test methods developed to fully exploit the specific design which they are selling. The search for the most appropriate instrument is a zealous task which is in itself part of the measurement.
The conditions under which the measurement is made has a considerable influence on the result. Both the temperature and humidity gradients across the sample need to be meas |
https://en.wikipedia.org/wiki/Charmed%20baryon | Charmed baryons are a category of composite particles comprising all baryons made of at least one charm quark. Since their first observation in the 1970s, a large number of distinct charmed baryon states have been identified. Observed charmed baryons have masses ranging between and . In 2002, the SELEX collaboration, based at Fermilab published evidence of a doubly charmed baryon (), containing two charm quarks) with a mass of ~, but has yet to be confirmed by other experiments. One triply charmed baryon () has been predicted but not yet observed.
Nomenclature
The nomenclature of charmed baryons is based on both quark content and isospin. The naming follows the rules established by the Particle Data Group.
Charmed baryons composed of one charm quark and two up, one up and one down, or two down quarks are known as charmed Lambdas (, isospin 0), or charmed Sigmas (, isospin 1).
Charmed baryons of isospin composed of one charm quark, and one up or down quark are known as charmed Xis () and all have isospin .
Charmed baryons composed of one charm quark and no up or down quarks are called charmed Omegas () and all have isospin 0.
Charmed baryons composed of two charm quarks and one up or down quark are called double charmed Xis () and all have isospin ).
Charmed baryons composed of two charm quarks and no up or down quarks are called double charmed Omega () and all have isospin 0.
Charmed baryons composed of three charm quarks are called triple charmed Omegas (), and all have isospin 0.
Charge is indicated with superscripts. Heavy quark (bottom, charm, or top quarks) content is indicated by subscripts. For example, a is made of one bottom, one charmed quark, and it can be deduced from the charge of the charm (+e) and bottom quark (−e) that the other quark must be an up quark (+e). Sometimes asterisks or primes are used to indicate a resonance.
Properties
The important parameters of charmed baryons, to be studied, consist of four properties. They are firstly |
https://en.wikipedia.org/wiki/Molehill | A molehill (or mole-hill, mole mound) is a conical mound of loose soil raised by small burrowing mammals, including moles, but also similar animals such as mole-rats, and voles. The word is first recorded in the first half of the 15th century. Formerly the hill was known as a 'wantitump', a word still in dialect use for centuries afterwards.
The phrase "making a mountain out of a molehill" is commonly used metaphorically to mean "to exaggerate a minor problem".
Evidence of burrows
Molehills are waste material which come from digging or repairing burrows, and so are usually found where the animal is establishing new burrows, or where existing ones are damaged (for example by the weight of grazing livestock). Where moles burrow beneath the roots of trees or shrubs, the roots support the tunnel, and molehills are less common, and so even a dense population of the animals may be inconspicuous in these places.
Molehills are often the only sign to indicate the presence of the animal and recording their presence may be the most reliable way to determine the number of moles in an area. Commonly they occur in lines along the route of the burrow, but in some cases they may not be directly above the burrow itself but at the ends of short side-tunnels. The mole runs vary in depth from surface runs only a few inches deep, to main runs, some 12 to 18 inches deep
The disturbance of the soil brings an important benefit by aerating and tilling it, adding to its fertility. Molehills are therefore sometimes used as a source of good soil for use in gardening and are particularly valued by some practitioners of permaculture for fine potting soil. However, they may cause damage to gardens and functional areas of grass such as pasture land, and they represent a minor safety hazard. King William III of England is recorded as dying from complications after he was thrown when his horse stumbled on one.
In locations where mole-hills are not desired, the moles may be killed, or deterren |
https://en.wikipedia.org/wiki/One-place%20study | One-place studies are a branch of family history and/or local history with a focus on the entire population of a single road, village or community, not just a single, geographically dispersed family line.
Introduction
In the course of a one-place study, a prime objective is to transcribe the registers of christenings, marriages and burials of the parish church so they can be restructured into family order in a database. This is then correlated with other archival records such as tax, land and testamentary documents, and published as a biographical index. When such a study is done scientifically as a precursor to academic analysis, it is known as family reconstitution.
The term one-place study is sometimes also used for a microhistory of a single urban street and its residents, including the changes in land ownership, agricultural or commercial activities.
Unlike a local history, which focuses on the past as described by residents, a one-place study can provide a statistical approach that reveals hidden relationships, particularly in homogeneous village communities where almost the entire population has inter-married over the centuries, and may even disprove local legends.
Development
The world's first major one-place study is believed to have been an attempt started in Austria in 1920 by Konrad Brandner to chart a complete genealogy of the population of the Steiermark region.
After the Nazi takeover of Germany, the Nazi farming authority Reichsnährstand began a nationwide campaign in 1937 to document the "Aryan blood" of countryfolk by documenting the ancestry of every village in a Dorfsippenbuch. 30 such books were published by 1940. Nazi schoolteachers led the copying of parish registers onto index cards, and boasted that 30,000 Heimat histories would be written, but the Second World War brought this project to a halt.
Though genealogy in Germany was to take decades to shake off this evil association, some enthusiasts resumed work on the card indexes or typ |
https://en.wikipedia.org/wiki/Ontology%20language | In computer science and artificial intelligence, ontology languages are formal languages used to construct ontologies. They allow the encoding of knowledge about specific domains and often include reasoning rules that support the processing of that knowledge. Ontology languages are usually declarative languages, are almost always generalizations of frame languages, and are commonly based on either first-order logic or on description logic.
Classification of ontology languages
Classification by syntax
Traditional syntax ontology languages
Common Logic - and its dialects
CycL
DOGMA (Developing Ontology-Grounded Methods and Applications)
F-Logic (Frame Logic)
FO-dot (First-order logic extended with types, arithmetic, aggregates and inductive definitions)
KIF (Knowledge Interchange Format)
Ontolingua based on KIF
KL-ONE
KM programming language
LOOM (ontology)
OCML (Operational Conceptual Modelling Language)
OKBC (Open Knowledge Base Connectivity)
PLIB (Parts LIBrary)
RACER
Markup ontology languages
These languages use a markup scheme to encode knowledge, most commonly with XML.
DAML+OIL
Ontology Inference Layer (OIL)
Web Ontology Language (OWL)
Resource Description Framework (RDF)
RDF Schema (RDFS)
SHOE
Controlled natural languages
Attempto Controlled English
Open vocabulary natural languages
Executable English
Classification by structure (logic type)
Frame-based
Three languages are completely or partially frame-based languages.
F-Logic
OKBC
KM
Description logic-based
Description logic provides an extension of frame languages, without going so far as to take the leap to first-order logic and support for arbitrary predicates.
KL-ONE
RACER
OWL.
Gellish is an example of a combined ontology language and ontology that is description logic based. It distinguishes between the semantic differences among others of:
relation types for relations between concepts (classes)
relation types for relations between individuals
relation types |
https://en.wikipedia.org/wiki/Almond%20meal | Almond meal, almond flour or ground almond is made from ground sweet almonds. Almond flour is usually made with blanched almonds (no skin), whereas almond meal can be made with whole or blanched almonds. The consistency is more like corn meal than wheat flour.
It is used in pastry and confectionery – in the manufacture of almond macarons and macaroons and other sweet pastries, in cake and pie filling, such as Austrian Sachertorte – and is one of the two main ingredients of marzipan and almond paste. In France, almond meal is an important ingredient in frangipane, the filling of traditional galette des Rois cake.
Almond meal has recently become important in baking items for those on low-carbohydrate diets. It adds moistness and a rich nutty taste to baked goods. Items baked with almond meal tend to be calorie-dense.
Almonds have high levels of polyunsaturated fats. Typically, the omega 6 fatty acids in almonds are protected from oxidation by the surface skin and vitamin E. When almonds are ground, this protective skin is broken and exposed surface area increases dramatically, greatly enhancing the nut's tendency to oxidize.
See also
Almond butter
List of almond dishes |
https://en.wikipedia.org/wiki/Almond%20paste | Almond paste is made from ground almonds or almond meal and sugar in equal quantities, with small amounts of cooking oil, beaten eggs, heavy cream or corn syrup added as a binder. It is similar to marzipan, but has a coarser texture. Almond paste is used as a filling in pastries, but it can also be found in chocolates. In commercially manufactured almond paste, ground apricot or peach kernels are sometimes added to keep the cost down (also known as persipan).
Uses
Almond paste is used as a filling in pastries of many different cultures. It is a chief ingredient of the American bear claw pastry. In the Nordic countries almond paste is used extensively, in various pastries and cookies. In Sweden (where it is known as mandelmassa) it is used in biscuits, muffins and buns and as a filling in the traditional Shrove Tuesday pastry semla and is used in Easter and Christmas sweets. In Denmark (where it is known as marcipan or mandelmasse), almond paste is used in several pastries, for example as a filling in the Danish traditional pastry kringle. In Finland almond paste (called mantelimassa) is used in chocolate pralines and in the Finnish version of the Shrove Tuesday pastry laskiaispulla.
In the Netherlands, almond paste (called amandelspijs) is used in gevulde speculaas (stuffed brown-spiced biscuit) and banket. It is used as filling in the fruited Christmas bread Kerststol, traditionally eaten at Christmas breakfast. In Germany, almond paste is also used in pastries and sweets. In the German language, almond paste is known as Marzipanrohmasse and sold for example as Lübecker Edelmarzipan, i.e. "high quality marzipan from Lübeck".
It Italy it's known as "pasta di mandorle". The soft paste is molded into creative shapes by pastry chefs which can be used as cake decorations or to make frutta martorana.
Almond paste is the main ingredient of French traditional calisson candy in Aix-en-Provence. It is used as a filling in almond croissants.
In Turkey, almond paste |
https://en.wikipedia.org/wiki/Silver%20Bells | "Silver Bells" is a Christmas song composed by Jay Livingston and Ray Evans.
The song is started by William Frawley, and then sung in the generally known version immediately thereafter by Bob Hope and Marilyn Maxwell in the motion picture The Lemon Drop Kid, which was filmed in July and August 1950 and released in March 1951. The first recorded version was sung by Bing Crosby and Carol Richards on September 8, 1950, with John Scott Trotter and His Orchestra and the Lee Gordon Singers. The recording was released by Decca Records in October 1950. After the Crosby/Richards recording became popular, Hope and Maxwell were called back in late 1950 to reshoot a more elaborate production of the song.
History
"Silver Bells" started out as "Tinkle Bells". Songwriter Ray Evans said: "We never thought that tinkle had a double meaning until Jay went home and his first wife said, 'Are you out of your mind? Do you know what the word tinkle is?'" Tinkle is a slang for urination.
This song's inspiration is the source of conflicting reports. Several periodicals and interviews cite writer Jay Livingston stating that the song's inspiration came from the bells used by sidewalk Santa Clauses and Salvation Army solicitors on New York City street corners. However, in an interview with NPR, co-writer Ray Evans said that the song was inspired by a bell that sat on an office desk that he shared with Livingston.
Kate Smith's 1966 version of "Silver Bells" became popular and has since been featured prominently in film and on holiday albums. The song was recorded by American country duo the Judds and was released as a single in 1987, charting for one week in 1998 at No. 68 on the Hot Country Songs chart. In 2009 the song charted in the United Kingdom for the first time when a duet by Terry Wogan and Aled Jones that had been recorded for charity reached the Top 40, peaking at No. 27.
See also
List of Christmas carols |
https://en.wikipedia.org/wiki/Anchovy%20essence | Anchovy essence is a brown or pink, thick, oily sauce, consisting of pounded anchovies, spices such as black pepper or cayenne pepper, and sometimes wine. It is used as a flavoring for soups, sauces, and other dishes since at least the 19th century. It has been called a British equivalent of Asian fish sauce.
See also |
https://en.wikipedia.org/wiki/Surface%20states | Surface states are electronic states found at the surface of materials. They are formed due to the sharp transition from solid material that ends with a surface and are found only at the atom layers closest to the surface. The termination of a material with a surface leads to a change of the electronic band structure from the bulk material to the vacuum. In the weakened potential at the surface, new electronic states can be formed, so called surface states.
Origin at condensed matter interfaces
As stated by Bloch's theorem, eigenstates of the single-electron Schrödinger equation with a perfectly periodic potential, a crystal, are Bloch waves
Here is a function with the same periodicity as the crystal, n is the band index and k is the wave number. The allowed wave numbers for a given potential are found by applying the usual Born–von Karman cyclic boundary conditions. The termination of a crystal, i.e. the formation of a surface, obviously causes deviation from perfect periodicity. Consequently, if the cyclic boundary conditions are abandoned in the direction normal to the surface the behavior of electrons will deviate from the behavior in the bulk and some modifications of the electronic structure has to be expected.
A simplified model of the crystal potential in one dimension can be sketched as shown in Figure 1. In the crystal, the potential has the periodicity, a, of the lattice while close to the surface it has to somehow attain the value of the vacuum level. The step potential (solid line) shown in Figure 1 is an oversimplification which is mostly convenient for simple model calculations. At a real surface the potential is influenced by image charges and the formation of surface dipoles and it rather looks as indicated by the dashed line.
Given the potential in Figure 1, it can be shown that the one-dimensional single-electron Schrödinger equation gives two qualitatively different types of solutions.
The first type of states (see figure 2) extends into |
https://en.wikipedia.org/wiki/Interferon%20tau | Interferon tau (IFNτ, IFNT) is a Type I interferon made of a single chain of amino acids. IFN-τ was first discovered in ruminants as the signal for the maternal recognition of pregnancy and originally named ovine trophoblast protein-1 (oTP-1). It has many physiological functions in the mammalian uterus, and also has anti-inflammatory effect that aids in the protection of the semi-allogeneic conceptus trophectoderm from the maternal immune system.
IFN-τ genes have only been found in ruminants that belong to the Artidactyla order, and multiple polymorphisms and several variants of IFN-τ have been identified. Although IFN-τ has been shown not to be produced in humans, both human and mouse cells respond to its effects. IFN-τ binds to the same IFN receptors as IFN-α and induces intracellular signalling through STAT1, STAT2, and Tyk2. This leads to the production of antiviral and immunomodulatory cytokines, including IL-4, IL-6, and IL-10.
Structure
IFN-τ consists of 172 amino acids with two disulfide bridges (1–99, 29–139) and amino terminal proline. Similar to other Type I interferons, IFN-τ binds to the Interferon-alpha/beta receptor (IFNAR).
Its molecular weight is between 19 and 24 kDa, depending on glycosylation state. Not all variants of IFN-τ are glycosylated. Bovine IFN-τ is N-glycosylated at ASN78, caprine IFN-τ is a combination between nonglycosylated and glycosylated forms and ovine IFN-τ is not glycosylated. Receptor binding site can be found at the C-terminus, biologically active site is located at the N-terminus.
Compared to other interferons, IFN-τ shares about 75% of its identity to IFN-ω, which can be found quite commonly in mammals. However, Southern blot analysis and genome sequencing data proved that genes encoding IFN-τ can be found only in ruminant species. Studies also show 85% sequence identity between human trophoblast IFN in placental trophoblast cells and IFN-τ.
Function and biological activity
IFN-τ is constitutively secreted by trophob |
https://en.wikipedia.org/wiki/Follicular%20phase | The follicular phase, also known as the preovulatory phase or proliferative phase, is the phase of the estrous cycle (or, in primates for example, the menstrual cycle) during which follicles in the ovary mature from primary follicle to a fully mature graafian follicle. It ends with ovulation. The main hormones controlling this stage are secretion of gonadotropin-releasing hormones, which are follicle-stimulating hormones and luteinising hormones. They are released by pulsatile secretion. The duration of the follicular phase can differ depending on the length of the menstrual cycle, while the luteal phase is usually stable, does not really change and lasts 14 days.
Hormonal events
Protein secretion
Due to the increase of FSH, the protein inhibin B will be secreted by the granulosa cells. Inhibin B will eventually blunt the secretion of FSH toward the end of the follicular phase. Inhibin B levels will be highest during the LH surge before ovulation and will quickly decrease after.
Follicle recruitment
Follicle-stimulating hormone (FSH) is secreted by the anterior pituitary gland (Figure 2). FSH secretion begins to rise in the last few days of the previous menstrual cycle, and is the highest and most important during the first week of the follicular phase (Figure 1). The rise in FSH levels recruits five to seven tertiary-stage ovarian follicles (this stage follicle is also known as a Graafian follicle or antral follicle) for entry into the menstrual cycle. These follicles, that have been growing for the better part of a year in a process known as folliculogenesis, compete with each other for dominance.
FSH induces the proliferation of granulosa cells in the developing follicles, and the expression of luteinizing hormone (LH) receptors on these granulosa cells (Figure 1). Under the influence of FSH, aromatase and p450 enzymes are activated, causing the granulosa cells to begin to secrete estrogen. This increased level of estrogen stimulates production of gonadotrop |
https://en.wikipedia.org/wiki/Hausdorff%20moment%20problem | In mathematics, the Hausdorff moment problem, named after Felix Hausdorff, asks for necessary and sufficient conditions that a given sequence be the sequence of moments
of some Borel measure supported on the closed unit interval . In the case , this is equivalent to the existence of a random variable supported on , such that .
The essential difference between this and other well-known moment problems is that this is on a bounded interval, whereas in the Stieltjes moment problem one considers a half-line , and in the Hamburger moment problem one considers the whole line . The Stieltjes moment problems and the Hamburger moment problems, if they are solvable, may have infinitely many solutions (indeterminate moment problem) whereas a Hausdorff moment problem always has a unique solution if it is solvable (determinate moment problem). In the indeterminate moment problem case, there are infinite measures corresponding to the same prescribed moments and they consist of a convex set. The set of polynomials may or may not be dense in the associated Hilbert spaces if the moment problem is indeterminate, and it depends on whether measure is extremal or not. But in the determinate moment problem case, the set of polynomials is dense in the associated Hilbert space.
Completely monotonic sequences
In 1921, Hausdorff showed that is such a moment sequence if and only if the sequence is completely monotonic, that is, its difference sequences satisfy the equation
for all . Here, is the difference operator given by
The necessity of this condition is easily seen by the identity
which is non-negative since it is the integral of a non-negative function. For example, it is necessary to have
See also
Total monotonicity |
https://en.wikipedia.org/wiki/Hamburger%20moment%20problem | In mathematics, the Hamburger moment problem, named after Hans Ludwig Hamburger, is formulated as follows: given a sequence (m0, m1, m2, ...), does there exist a positive Borel measure μ (for instance, the measure determined by the cumulative distribution function of a random variable) on the real line such that
In other words, an affirmative answer to the problem means that (m0, m1, m2, ...) is the sequence of moments of some positive Borel measure μ.
The Stieltjes moment problem, Vorobyev moment problem, and the Hausdorff moment problem are similar but replace the real line by (Stieltjes and Vorobyev; but Vorobyev formulates the problem in the terms of matrix theory), or a bounded interval (Hausdorff).
Characterization
The Hamburger moment problem is solvable (that is, (mn) is a sequence of moments) if and only if the corresponding Hankel kernel on the nonnegative integers
is positive definite, i.e.,
for every arbitrary sequence (cj)j ≥ 0 of complex numbers that are finitary (i.e. cj = 0 except for finitely many values of j).
For the "only if" part of the claims simply note that
which is non-negative if is non-negative.
We sketch an argument for the converse. Let Z+ be the nonnegative integers and F0(Z+) denote the family of complex valued sequences with finitary support. The positive Hankel kernel A induces a (possibly degenerate) sesquilinear product on the family of complex-valued sequences with finite support. This in turn gives a Hilbert space
whose typical element is an equivalence class denoted by [f].
Let en be the element in F0(Z+) defined by en(m) = δnm. One notices that
Therefore, the "shift" operator T on , with T[en] = [en + 1], is symmetric.
On the other hand, the desired expression
suggests that μ is the spectral measure of a self-adjoint operator. (More precisely stated, μ is the spectral measure for an operator defined below and the vector [1], ). If we can find a "function model" such that the symmetric operator T is multip |
https://en.wikipedia.org/wiki/Capacitively%20coupled%20plasma | A capacitively coupled plasma (CCP) is one of the most common types of industrial plasma sources. It essentially consists of two metal electrodes separated by a small distance, placed in a reactor. The gas pressure in the reactor can be lower than atmosphere or it can be atmospheric.
Description
A typical CCP system is driven by a single radio-frequency (RF) power supply, typically at 13.56 MHz. One of two electrodes is connected to the power supply, and the other one is grounded. As this configuration is similar in principle to a capacitor in an electric circuit, the plasma formed in this configuration is called a capacitively coupled plasma.
When an electric field is generated between electrodes, atoms are ionized and release electrons. The electrons in the gas are accelerated by the RF field and can ionize the gas directly or indirectly by collisions, producing secondary electrons. When the electric field is strong enough, it can lead to what is known as electron avalanche. After avalanche breakdown, the gas becomes electrically conductive due to abundant free electrons. Often it accompanies light emission from excited atoms or molecules in the gas. When visible light is produced, plasma generation can be indirectly observed even with bare eyes.
A variation on capacitively coupled plasma involves isolating one of the electrodes, usually with a capacitor. The capacitor appears like a short circuit to the high frequency RF field, but like an open circuit to direct current (DC) field. Electrons impinge on the electrode in the sheath, and the electrode quickly acquires a negative charge (or self-bias) because the capacitor does not allow it to discharge to ground. This sets up a secondary, DC field across the plasma in addition to the alternating current (AC) field. Massive ions are unable to react to the quickly changing AC field, but the strong, persistent DC field accelerates them toward the self-biased electrode. These energetic ions are exploited in m |
https://en.wikipedia.org/wiki/Pharyngeal%20arch | The pharyngeal arches, also known as visceral arches, are structures seen in the embryonic development of vertebrates that are recognisable precursors for many structures. In fish, the arches are known as the branchial arches, or gill arches.
In the human embryo, the arches are first seen during the fourth week of development. They appear as a series of outpouchings of mesoderm on both sides of the developing pharynx. The vasculature of the pharyngeal arches is known as the aortic arches.
In fish, the branchial arches support the gills.
Structure
In vertebrates, the pharyngeal arches are derived from all three germ layers (the primary layers of cells that form during embryogenesis). Neural crest cells enter these arches where they contribute to features of the skull and facial skeleton such as bone and cartilage. However, the existence of pharyngeal structures before neural crest cells evolved is indicated by the existence of neural crest-independent mechanisms of pharyngeal arch development. The first, most anterior pharyngeal arch gives rise to the oral jaw. The second arch becomes the hyoid and jaw support. In fish, the other posterior arches contribute to the branchial skeleton, which support the gills; in tetrapods the anterior arches develop into components of the ear, tonsils, and thymus. The genetic and developmental basis of pharyngeal arch development is well characterized. It has been shown that Hox genes and other developmental genes such as DLX are important for patterning the anterior/posterior and dorsal/ventral axes of the branchial arches. Some fish species have a second set of jaws in their throat, known as pharyngeal jaws, which develop using the same genetic pathways involved in oral jaw formation.
During human, and all vertebrate development, a series of pharyngeal arch pairs form in the developing embryo. These project forward from the back of the embryo toward the front of the face and neck. Each arch develops its own artery, nerve that |
https://en.wikipedia.org/wiki/Statistics%20Online%20Computational%20Resource | The Statistics Online Computational Resource (SOCR) is an online multi-institutional research and education organization. SOCR designs, validates and broadly shares a suite of online tools for statistical computing, and interactive materials for hands-on learning and teaching concepts in data science, statistical analysis and probability theory. The SOCR resources are platform agnostic based on HTML, XML and Java, and all materials, tools and services are freely available over the Internet.
The core SOCR components include interactive distribution calculators, statistical analysis modules, tools for data modeling, graphics visualization, instructional resources, learning activities and other resources.
All SOCR resources are licensed under either the Lesser GNU Public License or CC BY; peer-reviewed, integrated internally and interoperate with independent digital libraries developed by other professional societies and scientific organizations like NSDL, Open Educational Resources, Mathematical Association of America, California Digital Library, LONI Pipeline, etc.
See also
List of statistical packages
Comparison of statistical packages
External links
SOCR University of Michigan site
SOCR UCLA site |
https://en.wikipedia.org/wiki/CRAM-MD5 | In cryptography, CRAM-MD5 is a challenge–response authentication mechanism (CRAM) based on the HMAC-MD5 algorithm. As one of the mechanisms supported by the Simple Authentication and Security Layer (SASL), it is often used in email software as part of SMTP Authentication and for the authentication of POP and IMAP users, as well as in applications implementing LDAP, XMPP, BEEP, and other protocols.
When such software requires authentication over unencrypted connections, CRAM-MD5 is preferred over mechanisms that transmit passwords "in the clear," such as LOGIN and PLAIN. However, it can't prevent derivation of a password through a brute-force attack, so it is less effective than alternative mechanisms that avoid passwords or that use connections encrypted with Transport Layer Security (TLS).
Protocol
The CRAM-MD5 protocol involves a single challenge and response cycle, and is initiated by the server:
Challenge: The server sends a base64-encoded string to the client. Before encoding, it could be any random string, but the standard that currently defines CRAM-MD5 says that it is in the format of a Message-ID email header value (including angle brackets) and includes an arbitrary string of random digits, a timestamp, and the server's fully qualified domain name.
Response: The client responds with a string created as follows.
The challenge is base64-decoded.
The decoded challenge is hashed using HMAC-MD5, with a shared secret (typically, the user's password, or a hash thereof) as the secret key.
The hashed challenge is converted to a string of lowercase hex digits.
The username and a space character are prepended to the hex digits.
The concatenation is then base64-encoded and sent to the server
Comparison: The server uses the same method to compute the expected response. If the given response and the expected response match, then authentication was successful.
Strengths
The one-way hash and the fresh random challenge provide three types of security:
Others |
https://en.wikipedia.org/wiki/Benzyl%20acetate | Benzyl acetate is an organic ester with the molecular formula . It is formed by the condensation of benzyl alcohol and acetic acid.
Similar to most other esters, it possesses a sweet and pleasant aroma, owing to which, it finds applications in personal hygiene and health care products. It is a constituent of jasmin and of the essential oils of ylang-ylang and neroli. It has pleasant sweet aroma reminiscent of jasmine. Further as a flavoring agent it is also used to impart jasmine or apple flavors to various cosmetics and personal care products like lotions, hair creams etc..
It is one of many compounds that is attractive to males of various species of orchid bees. It is collected and used by the bees as an intra-specific pheromone; In apiculture benzyl acetate is used as a bait to collect bees. Natural sources of benzyl acetate include varieties of flowers like jasmine (Jasminum), and fruits like pear, apple, etc. |
https://en.wikipedia.org/wiki/Mees%27%20lines | Mees' lines or Aldrich–Mees lines, also called leukonychia striata, are white lines of discoloration across the nails of the fingers and toes (leukonychia).
Presentation
They are typically white bands traversing the width of the nail. As the nail grows they move towards the end, and finally disappear when trimmed.
Causes
Mees' lines appear after an episode of poisoning with arsenic, thallium or other heavy metals or selenium, opioid MT-45, and can also appear if the subject is suffering from kidney failure. They have been observed in chemotherapy patients.
Eponym and history
Although the phenomenon is named after Dutch physician R. A. Mees, who described the abnormality in 1919, earlier descriptions of the same abnormality were made by Englishman E. S. Reynolds in 1901 and by American C. J. Aldrich in 1904.
See also
Leukonychia
List of cutaneous conditions
Muehrcke's nails – a similar condition, except the lines are underneath the nails and so do not move as the nail grows |
https://en.wikipedia.org/wiki/Profilin | Profilin is an actin-binding protein involved in the dynamic turnover and reconstruction of the actin cytoskeleton. It is found in most eukaryotic organisms. Profilin is important for spatially and temporally controlled growth of actin microfilaments, which is an essential process in cellular locomotion and cell shape changes. This restructuring of the actin cytoskeleton is essential for processes such as organ development, wound healing, and the hunting down of infectious intruders by cells of the immune system.
Profilin also binds sequences rich in the amino acid proline in diverse proteins. While most profilin in the cell is bound to actin, profilins have over 50 different binding partners. Many of those are related to actin regulation, but profilin also seems to be involved in activities in the nucleus such as mRNA splicing.
Profilin is the major allergen (via IgE) present in birch, grass, and other pollen.
Sources and distribution
Profilins are proteins of molecular weights of roughly 14–19 kDa. They are present as single genes in yeast, insects, and worms, and as multiple genes in many other organisms including plants. In mammalian cells, four profilin isoforms have been discovered; profilin-I is expressed in most tissues while profilin-II is predominant in brain and kidney.
Asgard archaea use profilins. Multiple eukaryotic diatom species lack profilins.
Profilin is essential to host cell invasion by Toxoplasma gondii. Toxoplasma profilin is the specific pathogen-associated molecular pattern (PAMP) of TLRs 5, 11, and 12.
Regulation of actin dynamics
Profilin enhances actin growth in two ways:
Profilin binds to monomeric actin thereby occupying an actin-actin contact site; in effect, profilin sequesters actin from the pool of polymerizable actin monomers. However, profilin also catalyzes the exchange of actin-bound ADP to ATP thereby converting poorly polymerizing ADP-actin monomers into readily polymerizing ATP-actin monomers. On top of that, profilin |
https://en.wikipedia.org/wiki/Drug%20development | Drug development is the process of bringing a new pharmaceutical drug to the market once a lead compound has been identified through the process of drug discovery. It includes preclinical research on microorganisms and animals, filing for regulatory status, such as via the United States Food and Drug Administration for an investigational new drug to initiate clinical trials on humans, and may include the step of obtaining regulatory approval with a new drug application to market the drug. The entire process – from concept through preclinical testing in the laboratory to clinical trial development, including Phase I–III trials – to approved vaccine or drug typically takes more than a decade.
New chemical entity development
Broadly, the process of drug development can be divided into preclinical and clinical work.
Pre-clinical
New chemical entities (NCEs, also known as new molecular entities or NMEs) are compounds that emerge from the process of drug discovery. These have promising activity against a particular biological target that is important in disease. However, little is known about the safety, toxicity, pharmacokinetics, and metabolism of this NCE in humans. It is the function of drug development to assess all of these parameters prior to human clinical trials. A further major objective of drug development is to recommend the dose and schedule for the first use in a human clinical trial ("first-in-human" [FIH] or First Human Dose [FHD], previously also known as "first-in-man" [FIM]).
In addition, drug development must establish the physicochemical properties of the NCE: its chemical makeup, stability, and solubility. Manufacturers must optimize the process they use to make the chemical so they can scale up from a medicinal chemist producing milligrams, to manufacturing on the kilogram and ton scale. They further examine the product for suitability to package as capsules, tablets, aerosol, intramuscular injectable, subcutaneous injectable, or intravenous f |
https://en.wikipedia.org/wiki/Five%20Grains | The Five Grains or Cereals () are a grouping (or set of groupings) of five farmed crops that were all important in ancient China. Sometimes the crops themselves were regarded as sacred; other times, their cultivation was regarded as a sacred boon from a mythological or supernatural source. More generally, wǔgǔ can be employed in Chinese as a synecdoche referring to all grains or staple crops of which the end produce is of a granular nature. The identity of the five grains has varied over time, with different authors identifying different grains or even categories of grains.
Holiness
The sense of holiness or sacredness regarding the Five Grains proceeds from their traditional ascription to the saintly rulers credited with creating China's civilization. They were seen not merely as five crops chosen from many options but as the source permitting agrarian society and civilization itself. "Squandering the Five Grains" was seen as a sin worthy of torment in Diyu, the Chinese hell.
As the position of emperor was seen as an embodiment of this society, one's behavior towards the Five Grains could take on political meaning: as a protest against the overthrow of the Shang Dynasty by the Zhou, Boyi and Shuqi ostentatiously refused to eat the Five Grains. Such rejections of the grains for political reasons underwent a complex development into the concept of bigu, the esoteric Taoist practice of achieving immortality by avoiding certain foods.
Legendary accounts
By the time of written records, the development of agriculture in China had become greatly mythologized. There were various traditions regarding which of the early Chinese leaders introduced the Five Grains:
Shennong
Shennong (神農) (lit. "Divine Farmer") was a Chinese culture hero credited with the development of agriculture. He was often conflated with Yandi (the "Flaming Emperor") and is also sometimes described as the Wugu Xiandi or "Divine Emperor of the Five Grains". Sima Qian's chronology placed him around 273 |
https://en.wikipedia.org/wiki/Hot%20spare | A hot spare or warm spare or hot standby is used as a failover mechanism to provide reliability in system configurations. The hot spare is active and connected as part of a working system. When a key component fails, the hot spare is switched into operation. More generally, a hot standby can be used to refer to any device or system that is held in readiness to overcome an otherwise significant start-up delay.
Examples
Examples of hot spares are components such as A/V switches, computers, network printers, and hard disks. The equipment is powered on, or considered "hot," but not actively functioning in (i.e. used by) the system.
Electrical generators may be held on hot standby, or a steam train may be held at the shed fired up (literally hot) ready to replace a possible failure of an engine in service.
Explanation
In designing a reliable system, it is recognized that there will be failures. At the extreme, a complete system can be duplicated and kept up to date—so in the event of the primary system failing, the secondary system can be switched in with little or no interruption. More often, a hot spare is a single vital component without which the entire system would fail. The spare component is integrated into the system in such a way that in the event of a problem, the system can be altered to use the spare component. This may be done automatically or manually, but in either case it is normal to have some means of error detection. A hot spare does not necessarily give 100% availability or protect against temporary loss of the system during the switching process; it is designed to significantly reduce the time that the system is unavailable.
Hot standby may have a slightly different connotation of being active but not productive to hot spare, that is it is a state rather than object. For example, in a national power grid, the supply of power needs to be balanced to demand over a short term. It can take many hours to bring a coal-fired power station up to produ |
https://en.wikipedia.org/wiki/Natural%20heritage | Natural heritage refers to the sum total of the elements of biodiversity, including flora and fauna, ecosystems and geological structures. It forms part of our natural resources.
Definition
Heritage is that which is inherited from past generations, maintained in the present, and bestowed to future generations. The term "natural heritage", derived from "natural inheritance", pre-dates the term "biodiversity". It is a less scientific term and more easily comprehended in some ways by the wider audience interested in conservation.
The term was used in this context in the United States when Jimmy Carter set up the Georgia Heritage Trust while he was governor of Georgia; Carter's trust dealt with both natural and cultural heritage. It would appear that Carter picked the term up from Lyndon Johnson, who used it in a 1966 Message to Congress. (He may have gotten the term from his wife Lady Bird Johnson who was personally interested in conservation.) President Johnson signed the Wilderness Act of 1964.
The term "Natural Heritage" was picked up by the Science Division of The Nature Conservancy (TNC) when, under Robert E. Jenkins, Jr., it launched in 1974 what ultimately became the network of state natural heritage programs—one in each state, all using the same methodology and all supported permanently by state governments because they scientifically document conservation priorities and facilitate science-based environmental reviews. When this network was extended outside the United States, the term "Conservation Data Center (or Centre)" was suggested by Guillermo Mann and came to be preferred for programs outside the US. Despite the name difference, these programs, too, use the same core methodology as the 50 state natural heritage programs. In 1994 The network of natural heritage programs formed a membership association to work together on projects of common interest: the Association for Biodiversity Information (ABI). In 1999, Through an agreement with The Nature |
https://en.wikipedia.org/wiki/Myrcene | Myrcene, or β-myrcene, is a monoterpene. A colorless oil, it occurs widely in essential oils. It is produced mainly semi-synthetically from Myrcia, from which it gets its name. It is an intermediate in the production of several fragrances. α-Myrcene is the name for the isomer 2-methyl-6-methylene-1,7-octadiene, which has not been found in nature.
Production
Myrcene is often produced commercially by the pyrolysis (400 °C) of β-pinene, which is obtained from turpentine. It is rarely obtained directly from plants.
Plants biosynthesize myrcene via geranyl pyrophosphate (GPP), which isomerizes into linalyl pyrophosphate. The release of the pyrophosphate (OPP) and a proton completes the conversion.
Occurrence
It could in principle be extracted from any number of plants, such as verbena or wild thyme, the leaves of which contain up to 40% by weight of myrcene. Many other plants contain myrcene, sometimes in substantial amounts. Some of these include cannabis, hops, Houttuynia, lemon grass, mango, Myrcia, West Indian bay tree, and cardamom.
Of the several terpenes extracted from Humulus lupulus (hops), the largest monoterpenes fraction is β-myrcene. One study of the chemical composition of the fragrance of Cannabis sativa found β-myrcene to compose between 29.4% and 65.8% of the steam-distilled essential oil for the set of fiber and drug strains tested. Additionally, myrcene is thought to be the predominant terpene found in modern cannabis cultivars within North America. Interestingly, photo-oxidation of myrcene has been shown to rearrange the molecule into a novel terpene known as "hashishene" which is named for its abundance in hashish.
It is found in the South African Adenandra villosa (50%). & Brazilian Schinus molle (40%) Myrcene is also found in Myrcia cuprea petitgrain (up to 48%), bay leaf, juniper berry, cannabis, and hops.
Use in fragrance and flavor industries
Myrcene is an intermediate used in the perfumery industry. It has a pleasant odor but is rarely |
https://en.wikipedia.org/wiki/Blind%20wine%20tasting | Blinded wine tasting is wine tasting undertaken in circumstances in which the tasters are kept unaware of the wines' identities. The blind approach is routine for wine professionals (wine tasters, sommeliers and others) who wish to ensure impartiality in the judgment of the quality of wine during wine competitions or in the evaluation of a sommelier for professional certification. More recently wine scientists (physiologists, psychologists, food chemists and others) have used blinded tastings to explore the objective parameters of the human olfactory system as they apply to the ability of wine drinkers (both wine professionals and ordinary consumers) to identify and characterize the extraordinary variety of compounds that contribute to a wine’s aroma. Similarly, economists testing hypotheses relating to the wine market have used the technique in their research. Some blinded trials among wine consumers have indicated that people can find nothing in a wine's aroma or taste to distinguish between ordinary and pricey brands. Academic research on blinded wine tastings have also cast doubt on the ability of professional tasters to judge wines consistently.
Technique
Blind tasting, at a minimum, involves denying taster(s) the ability to see the wine label or wine bottle shape. Informal tastings may simply conceal the bottles in a plain paper bag. More exacting competitions or evaluations utilize more stringent procedures, including safeguards against cheating. For example, the wine may be tasted from a black wine glass to mask the color .
Biases
A taster's judgment can be prejudiced by knowing details of a wine, such as geographic origin, price, reputation, color, or other considerations.
Scientific research has long demonstrated the power of suggestion in perception as well as the strong effects of expectancies. For example, people expect more expensive wine to have more desirable characteristics than less expensive wine. When given wine that they are falsely told is e |
https://en.wikipedia.org/wiki/Free%20will%20theorem | The free will theorem of John H. Conway and Simon B. Kochen states that if we have a free will in the sense that our choices are not a function of the past, then, subject to certain assumptions, so must some elementary particles. Conway and Kochen's paper was published in Foundations of Physics in 2006. In 2009, the authors published a stronger version of the theorem in the Notices of the American Mathematical Society. Later, in 2017, Kochen elaborated some details.
Axioms
The proof of the theorem as originally formulated relies on three axioms, which Conway and Kochen call "fin", "spin", and "twin". The spin and twin axioms can be verified experimentally.
Fin: There is a maximal speed for propagation of information (not necessarily the speed of light). This assumption rests upon causality.
Spin: The squared spin component of certain elementary particles of spin one, taken in three orthogonal directions, will be a permutation of (1,1,0).
Twin: It is possible to "entangle" two elementary particles and separate them by a significant distance, so that they have the same squared spin results if measured in parallel directions. This is a consequence of quantum entanglement, but full entanglement is not necessary for the twin axiom to hold (entanglement is sufficient but not necessary).
In their later 2009 paper, "The Strong Free Will Theorem", Conway and Kochen replace the Fin axiom by a weaker one called Min, thereby strengthening the theorem. The Min axiom asserts only that two experimenters separated in a space-like way can make choices of measurements independently of each other. In particular it is not postulated that the speed of transfer of all information is subject to a maximum limit, but only of the particular information about choices of measurements. In 2017, Kochen argued that Min could be replaced by Lin – experimentally testable Lorentz covariance.
The theorem
The free will theorem states:
That is an "outcome open" theorem.
Since the theorem ap |
https://en.wikipedia.org/wiki/P-Cymene | p-Cymene is a naturally occurring aromatic organic compound. It is classified as an alkylbenzene related to monocyclic monoterpenes. Its structure consists of a benzene ring para-substituted with a methyl group and an isopropyl group. p-Cymene is insoluble in water, but miscible with organic solvents.
Isomers and production
In addition to p-cymene, two less common geometric isomers are o-cymene, in which the alkyl groups are ortho-substituted, and m-cymene, in which they are meta-substituted. p-Cymene is the only natural isomer, as expected from the terpene rule. All three isomers form the group of cymenes.
Cymene is also produced by alkylation of toluene with propene.
Related compounds
It is a constituent of a number of essential oils, most commonly the oil of cumin and thyme. Significant amounts are formed in sulfite pulping process from the wood terpenes.
p-Cymene is a common ligand for ruthenium. The parent compound is [(η6-cymene)RuCl2]2. This half-sandwich compound is prepared by the reaction of ruthenium trichloride with the terpene α-phellandrene. The osmium complex is also known.
Hydrogenation gives the saturated derivative p-menthane. |
https://en.wikipedia.org/wiki/Mechanical%20impedance | Mechanical impedance is a measure of how much a structure resists motion when subjected to a harmonic force. It relates forces with velocities acting on a mechanical system. The mechanical impedance of a point on a structure is the ratio of the force applied at a point to the resulting velocity at that point.
Mechanical impedance is the inverse of mechanical admittance or mobility. The mechanical impedance is a function of the frequency of the applied force and can vary greatly over frequency. At resonance frequencies, the mechanical impedance will be lower, meaning less force is needed to cause a structure to move at a given velocity. A simple example of this is pushing a child on a swing. For the greatest swing amplitude, the frequency of the pushes must be near the resonant frequency of the system.
Where, is the force vector, is the velocity vector, is the impedance matrix and is the angular frequency.
Mechanical impedance is the ratio of a potential (e.g., force) to a flow (e.g., velocity) where the arguments of the real (or imaginary) parts of both increase linearly with time. Examples of potentials are: force, sound pressure, voltage, temperature. Examples of flows are: velocity, volume velocity, current, heat flow. Impedance is the reciprocal of mobility. If the potential and flow quantities are measured at the same point then impedance is referred as driving point impedance; otherwise, transfer impedance.
Resistance - the real part of an impedance.
Reactance - the imaginary part of an impedance.
See also
Acoustic impedance
Frequency response
Impedance analogy
Linear response function |
https://en.wikipedia.org/wiki/Landscape%20of%20Geometry | Landscape of Geometry was an educational television show that illustrated the principles and applications of geometry. The series was produced and broadcast by TVOntario in 1982–83 and was hosted by David Stringer. A videotape edition of the show was produced in 1992 by Films for the Humanities.
Episode list
Eight episodes were produced. They were:
"The Shape of Things"
"It's Rude to Point"
"Lines That Cross"
"Lines That Don't Cross"
"Up, Down, and Sideways"
"Trussworthy"
"Cracked Up"
"The Range of Change"
All episodes were 15 minutes in length. |
https://en.wikipedia.org/wiki/Barium%20titanate | Barium titanate (BTO) is an inorganic compound with chemical formula BaTiO3. Barium titanate appears white as a powder and is transparent when prepared as large crystals. It is a ferroelectric, pyroelectric, and piezoelectric ceramic material that exhibits the photorefractive effect. It is used in capacitors, electromechanical transducers and nonlinear optics.
Structure
The solid exists in one of four polymorphs depending on temperature. From high to low temperature, these crystal symmetries of the four polymorphs are cubic, tetragonal, orthorhombic and rhombohedral crystal structure. All of these phases exhibit the ferroelectric effect apart from the cubic phase. The high temperature cubic phase is easiest to describe, as it consists of regular corner-sharing octahedral TiO6 units that define a cube with O vertices and Ti-O-Ti edges. In the cubic phase, Ba2+ is located at the center of the cube, with a nominal coordination number of 12. Lower symmetry phases are stabilized at lower temperatures and involve movement of the Ti4+ to off-center positions. The remarkable properties of this material arise from the cooperative behavior of the Ti4+ distortions.
Above the melting point, the liquid has a remarkably different local structure to the solid forms, with the majority of Ti4+ coordinated to four oxygen, in tetrahedral TiO4 units, which coexist with more highly coordinated units.
Production and handling properties
Barium titanate can be synthesized by the relatively simple sol–hydrothermal method.
Barium titanate can also be manufactured by heating barium carbonate and titanium dioxide. The reaction proceeds via liquid phase sintering. Single crystals can be grown at around 1100 °C from molten potassium fluoride. Other materials are often added as dopants, e.g., Sr to form solid solutions with strontium titanate. It reacts with nitrogen trichloride and produces a greenish or gray mixture; the ferroelectric properties of the mixture are still present i |
https://en.wikipedia.org/wiki/Metabolic%20rift | Metabolic rift is Karl Marx's key conception of ecological crisis tendencies under capitalism, or in Marx's own words, it is the "irreparable rift in the interdependent process of social metabolism". Marx theorized a rupture in the metabolic interaction between humanity and the rest of nature emanating from capitalist agricultural production and the growing division between town and country.
According to John Bellamy Foster, who coined the term, metabolic rift is the development of Marx's earlier work in the Economic and Philosophical Manuscripts on species-being and the relationship between humans and nature. Metabolism is Marx's "mature analysis of the alienation of nature" and presents "a more solid—and scientific—way in which to depict the complex, dynamic interchange between human beings and nature, resulting from human labor."
As opposed to those who have attributed to Marx a disregard for nature and responsibility for the environmental problems of the Soviet Union and other purportedly communist states, Foster sees in the theory of metabolic rift evidence of Marx's ecological perspective. The theory of metabolic rift "enable[ed] [Marx] to develop a critique of environmental degradation that anticipated much of present-day ecological thought", including questions of sustainability as well as the limits of agricultural production using concentrated animal feeding operations. Researchers building on the original Marxist concept have developed other similar terms like carbon rift.
Origins
Soil exhaustion and agricultural revolutions
Marx's writings on metabolism were developed during England's "second" agricultural revolution (1815–1880), a period which was characterized by the development of soil chemistry and the growth of the use of chemical fertilizer. The depletion of soil fertility, or "soil exhaustion", had become a key concern for capitalist society, and demand for fertilizer was such that Britain and other powers initiated explicit policies for the |
https://en.wikipedia.org/wiki/Photodissociation | Photodissociation, photolysis, photodecomposition, or photofragmentation is a chemical reaction in which molecules of a chemical compound are broken down by photons. It is defined as the interaction of one or more photons with one target molecule.
Photodissociation is not limited to visible light. Any photon with sufficient energy can affect the chemical bonds of a chemical compound. Since a photon's energy is inversely proportional to its wavelength, electromagnetic radiations with the energy of visible light or higher, such as ultraviolet light, X-rays, and gamma rays can induce such reactions.
Photolysis in photosynthesis
Photolysis is part of the light-dependent reaction or light phase or photochemical phase or Hill reaction of photosynthesis. The general reaction of photosynthetic photolysis can be given in terms of photons as:
The chemical nature of "A" depends on the type of organism. Purple sulfur bacteria oxidize hydrogen sulfide () to sulfur (S). In oxygenic photosynthesis, water () serves as a substrate for photolysis resulting in the generation of diatomic oxygen (). This is the process which returns oxygen to Earth's atmosphere. Photolysis of water occurs in the thylakoids of cyanobacteria and the chloroplasts of green algae and plants.
Energy transfer models
The conventional semi-classical model describes the photosynthetic energy transfer process as one in which excitation energy hops from light-capturing pigment molecules to reaction center molecules step-by-step down the molecular energy ladder.
The effectiveness of photons of different wavelengths depends on the absorption spectra of the photosynthetic pigments in the organism. Chlorophylls absorb light in the violet-blue and red parts of the spectrum, while accessory pigments capture other wavelengths as well. The phycobilins of red algae absorb blue-green light which penetrates deeper into water than red light, enabling them to photosynthesize in deep waters. Each absorbed photon causes |
https://en.wikipedia.org/wiki/Hibernation%20%28computing%29 | Hibernation (also known as suspend to disk, or Safe Sleep on Macintosh computers) in computing is powering down a computer while retaining its state. When hibernation begins, the computer saves the contents of its random access memory (RAM) to a hard disk or other non-volatile storage. When the computer is turned on the RAM is restored and the computer is exactly as it was before entering hibernation. Hibernation was first implemented in 1992 and patented by Compaq Computer Corporation in Houston, Texas. Microsoft's Windows 10 employs a type of hibernation (fast startup) by default when shutting down.
Uses
After hibernating, the hardware is powered down like a regular shutdown. The system can have a total loss of power for an indefinite length of time and then resume to the original state. Hibernation is mostly used in laptops, which have limited battery power available. It can be set to happen automatically on a low battery alarm. Most desktops also support hibernation, mainly as a general energy saving measure and allows for replacement of a removable battery quickly. Google and Apple mobile hardware (Android, Chromebooks, iOS) do not support hibernation. Apple hardware using macOS calls hibernation Safe Sleep.
Comparison to sleep mode
Many systems support a low-power sleep mode in which the processing functions of the machine are lowered, using a trickle of power to preserve the contents of RAM and support waking up. Instantaneous resumption is one of the advantages of sleep mode over hibernation. A hibernated system must start up and read data from permanent storage and then transfer that back to RAM, which takes longer and depends on the speed of the permanent storage device, often much slower than RAM memory. A system in sleep mode only needs to power up the CPU and display, which is almost instantaneous. On the other hand, a system in sleep mode still consumes power to keep the data in the RAM. Detaching power from a system in sleep mode results in da |
https://en.wikipedia.org/wiki/Polyfuse%20%28PROM%29 | A polyfuse is a one-time-programmable memory component used in semiconductor circuits for storing unique data like chip identification numbers or memory repair data, but more usually small to medium volume production of read only memory devices or microcontroller chips. They were also used as to permit programming of Programmable Array Logic. The use of fuses allowed the device to be programmed electrically some time after it was manufactured and sealed into its packaging. Earlier fuses had to be blown using a laser at the time memory was manufactured. Polyfuses were developed to replace the earlier nickel-chromium (ni-chrome) fuses. Because ni-chrome contains nickel, the ni-chrome fuse, once blown had a tendency to grow back and render the memory unusable.
History
The first polyfuses consisted of a polysilicon line, which was programmed by applying a high (10V-15V) voltage across the device. The resultant current physically alters the device and increases its electrical resistance. This change in resistance can be detected and registered as a logical zero. An unprogrammed polyfuse would be registered as a logical one. These early devices had severe drawbacks like a high programming voltage and unreliability of the programmed devices.
Modern polyfuses
Modern polyfuses consist of a silicided polysilicon line, which is also programmed by applying a voltage across the device. Again, the resultant current permanently alters the resistance. The silicide layer covering the polysilicon line reduces its resistance (before programming), allowing the use of much lower programming voltages (1.8V–3.3V). Polyfuses have been shown to reliably store programmed data and can be programmed at high speed. Programming speeds of 100ns have been reported.
See also
Programmable read-only memory |
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