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https://en.wikipedia.org/wiki/Fluidized%20bed
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A fluidized bed is a physical phenomenon that occurs when a solid particulate substance (usually present in a holding vessel) is under the right conditions so that it behaves like a fluid. The usual way to achieve a fluidized bed is to pump pressurized fluid into the particles. The resulting medium then has many properties and characteristics of normal fluids, such as the ability to free-flow under gravity, or to be pumped using fluid technologies.
The resulting phenomenon is called fluidization. Fluidized beds are used for several purposes, such as fluidized bed reactors (types of chemical reactors), solids separation, fluid catalytic cracking, fluidized bed combustion, heat or mass transfer or interface modification, such as applying a coating onto solid items. This technique is also becoming more common in aquaculture for the production of shellfish in integrated multi-trophic aquaculture systems.
Properties
A fluidized bed consists of fluid-solid mixture that exhibits fluid-like properties. As such, the upper surface of the bed is relatively horizontal, which is analogous to hydrostatic behavior. The bed can be considered to be a heterogeneous mixture of fluid and solid that can be represented by a single bulk density.
Furthermore, an object with a higher density than the bed will sink, whereas an object with a lower density than the bed will float, thus the bed can be considered to exhibit the fluid behavior expected of Archimedes' principle. As the "density", (actua
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https://en.wikipedia.org/wiki/PGM
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PGM may refer to:
Math and science
Phosphoglucomutase, an enzyme that interconverts G6P and G1P
Phosphoglycerate mutase, an enzyme that catalyses step 8 of glycolysis
Platinum group metals, six metallic elements grouped together on the periodic table of the elements
Probabilistic graphical model, which can be directed or undirected
Computers
Portable Graymap File Format, a Netpbm format file format for images
Pragmatic General Multicast, an Internet transport protocol for reliable multicast
Military and navy
Precision-guided munition, a term for a guided weapon
PGM Précision, a French precision weapon maker
Patrol Gunboat Motor, PGM-39-class gunboat used in the United States Navy's ship classification system
Music
Ibanez PGM, the signature guitar model of Paul Gilbert
Playground Music Scandinavia, a Swedish record label
Other
Greek Magical Papyri, a collection of ancient texts also known as the Papyri Graecae Magicae
Past Grand Master, the former head of the Grand Masonic lodge
Provincial Grand Master (PGM or PrGM), the ruler of an internal masonic province
Honda's programmed fuel injection system
PolyGame Master, an arcade system board made by IGS
PGM Inspection Company
Proto-Germanic, the reconstructed ancestor of all Germanic languages
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https://en.wikipedia.org/wiki/Sulfonucleotide%20reductase
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Sulfonucleotide reductases are a class of enzymes involved in reductive sulfur assimilation. This reaction consists of a conversion from activated sulfate to sulfite. (Inorganic sulfate occurs abundantly on Earth; terrestrial organisms must use sulfate assimilation to convert it to sulfide). The sulfite is used in essential biomolecules such as cysteine. The sulfonucleotide reductases are through to have all evolved from a common ancestor.
The enzymes reduce adenosine-5'-phosphosulfate by nucleophilic attack to produce the sulfite product. This typically involves a cofactor (such as an iron-sulphur cluster), however the cofactor varies in different families.
References
Sulfur metabolism
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https://en.wikipedia.org/wiki/Resonant%20trans-Neptunian%20object
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In astronomy, a resonant trans-Neptunian object is a trans-Neptunian object (TNO) in mean-motion orbital resonance with Neptune. The orbital periods of the resonant objects are in a simple integer relations with the period of Neptune, e.g. 1:2, 2:3, etc. Resonant TNOs can be either part of the main Kuiper belt population, or the more distant scattered disc population.
Distribution
The diagram illustrates the distribution of the known trans-Neptunian objects. Resonant objects are plotted in red.
Orbital resonances with Neptune are marked with vertical bars: 1:1 marks the position of Neptune's orbit and its trojans; 2:3 marks the orbit of Pluto and plutinos; and 1:2, 2:5, etc. mark a number of smaller families. The designation 2:3 or 3:2 both refer to the same resonance for TNOs. There is no ambiguity, because TNOs have, by definition, periods longer than Neptune's. The usage depends on the author and the field of research.
Origin
Detailed analytical and numerical studies of Neptune's resonances have shown that the objects must have a relatively precise range of energies. If the object's semi-major axis is outside these narrow ranges, the orbit becomes chaotic, with widely changing orbital elements. As TNOs were discovered, more than 10% were found to be in 2:3 resonances, far from a random distribution. It is now believed that the objects have been collected from wider distances by sweeping resonances during the migration of Neptune. Well before the discovery of the firs
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https://en.wikipedia.org/wiki/Malonyl-CoA
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Malonyl-CoA is a coenzyme A derivative of malonic acid.
Functions
It plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis.
Cytosolic fatty acid biosynthesis
Malonyl-CoA provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis.
Malonyl-CoA is formed by carboxylating acetyl-CoA using the enzyme acetyl-CoA carboxylase. One molecule of acetyl-CoA joins with a molecule of bicarbonate, requiring energy rendered from ATP.
Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT). MCAT serves to transfer malonate from malonyl-CoA to the terminal thiol of holo-acyl carrier protein (ACP).
Mitochondrial fatty acid synthesis
Malonyl-CoA is formed in the first step of mitochondrial fatty acid synthesis (mtFASII) from malonic acid by malonyl-CoA synthetase (ACSF3).
Polyketide biosynthesis
MCAT is also involved in bacterial polyketide biosynthesis. The enzyme MCAT together with an acyl carrier protein (ACP), and a polyketide synthase (PKS) and chain-length factor heterodimer, constitutes the minimal PKS of type II polyketides.
Regulation
Malonyl-CoA is a highly regulated molecule in fatty acid synthesis; as such, it inhibits the rate-limiting step in beta-oxidation of fatty acids. Malonyl-CoA inhibits fatty acids from associating with carnitine by regulating the enzyme carnitine acyltransferase, thereby preventing them from entering the mitochondria
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https://en.wikipedia.org/wiki/Acyl%20carrier%20protein
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The acyl carrier protein (ACP) is a cofactor of both fatty acid and polyketide biosynthesis machinery. It is one of the most abundant proteins in cells of E. coli. In both cases, the growing chain is bound to the ACP via a thioester derived from the distal thiol of a 4'-phosphopantetheine moiety.
Structure
The ACPs are small negatively charged α-helical bundle proteins with a high degree of structural and amino acid similarity. The structures of a number of acyl carrier proteins have been solved using various NMR and crystallography techniques. The ACPs are related in structure and mechanism to the peptidyl carrier proteins (PCP) from nonribosomal peptide synthases.
Biosynthesis
Subsequent to the expression of the inactive apo ACP, the 4'-phosphopantetheine moiety is attached to a serine residue. This coupling is mediated by acyl carrier protein synthase (ACPS), a 4'-phosphopantetheinyl transferase. 4'-Phosphopantetheine is a prosthetic group of several acyl carrier proteins including the acyl carrier proteins (ACP) of fatty acid synthases, ACPs of polyketide synthases, the peptidyl carrier proteins (PCP), as well as aryl carrier proteins (ArCP) of nonribosomal peptide synthetases (NRPS).
References
External links
Proteins
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https://en.wikipedia.org/wiki/Gershgorin%20circle%20theorem
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In mathematics, the Gershgorin circle theorem may be used to bound the spectrum of a square matrix. It was first published by the Soviet mathematician Semyon Aronovich Gershgorin in 1931. Gershgorin's name has been transliterated in several different ways, including Geršgorin, Gerschgorin, Gershgorin, Hershhorn, and Hirschhorn.
Statement and proof
Let be a complex matrix, with entries . For let be the sum of the absolute values of the non-diagonal entries in the -th row:
Let be a closed disc centered at with radius . Such a disc is called a Gershgorin disc.
Theorem. Every eigenvalue of lies within at least one of the Gershgorin discs
Proof. Let be an eigenvalue of with corresponding eigenvector . Find i such that the element of x with the largest absolute value is . Since , in particular we take the ith component of that equation to get:
Taking to the other side:
Therefore, applying the triangle inequality and recalling that based on how we picked i,
Corollary. The eigenvalues of A must also lie within the Gershgorin discs Cj corresponding to the columns of A.
Proof. Apply the Theorem to AT while recognizing that the eigenvalues of the transpose are the same as those of the original matrix.
Example. For a diagonal matrix, the Gershgorin discs coincide with the spectrum. Conversely, if the Gershgorin discs coincide with the spectrum, the matrix is diagonal.
Discussion
One way to interpret this theorem is that if the off-diagonal entries of a
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https://en.wikipedia.org/wiki/Earth%202%20%28album%29
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Earth 2: Special Low Frequency Version, also known as simply Earth 2, is the first full-length studio album by the American drone metal band Earth. Produced by Earth and Stuart Hallerman, it was released on February 5, 1993, on Sub Pop Records. The album was highly influential in the development of the drone music and drone metal genres.
Background
At the time of Earth's formation, bandleader Dylan Carlson was conceptually influenced by minimalist composers such as La Monte Young as well the bands King Crimson and Slayer. As a child, Carlson was a fan of classic rock groups such as AC/DC, noting that "when I would hear a song and there’d be a cool riff or a cool part of the song I was always like, 'Oh, what would it be like if they stayed on that instead of moving on to the next part?' Then I read about minimalism and stuff like that. I was like, 'Oh, what if we take a Slayer-style riff and play it for 20 minutes at half speed?' I guess you could say that was my one good idea."
The recent advent of compact discs allowed for playing times up to 74 minutes, which encouraged the group to "fill up an entire CD with one song in three parts." However, recording tape only allowed for 30 minutes max at the time, so that the band needed to "sort of splice it or fade it in and fade up, stuff like that" to achieve the longer recording. The group were signed to grunge label Sub Pop, but Carlson explained that "what we did was not grunge and not part of that whole thing. A lot of people
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https://en.wikipedia.org/wiki/Nippon%20Decimal%20Classification
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The Nippon Decimal Classification (NDC, also called the Nippon Decimal System) is a system of library classification developed for mainly Japanese-language books maintained and revised by the Japan Library Association since 1948. Originally developed in 1929 by Kiyoshi Mori, the 10th and latest edition of this system was published in 2014. The decimal notation system is similar to the Dewey Decimal System, and the order of main classes is inspired from the Cutter Expansive Classification. The system is based upon using a three digit number to classify subjects, where more digits can be added if necessary and a decimal point is used to separate the third and fourth digit. The first division level is called a class, the second level is called a division, and the third level is called a section. Each '1-9' digit is used to represent a specific category, with the digit '0' being used to represent general works.
Main classes
The system is made up of ten categories:
000 General
100 Philosophy
200 History
300 Social sciences
400 Natural sciences
500 Technology
600 Industry
700 Arts
800 Language
900 Literature
Description of the Divisions
000 General
The General category contains books that contain general information, rather than information about specific topics. The sub-categories of the General category are:
010 Libraries, Library & information science
020 Books, Bibliography
030 Encyclopaedias
040 General collected essays
050 General serial publications
060 Gene
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https://en.wikipedia.org/wiki/Apical%20dendrite
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An apical dendrite is a dendrite that emerges from the apex of a pyramidal cell. Apical dendrites are one of two primary categories of dendrites, and they distinguish the pyramidal cells from spiny stellate cells in the cortices. Pyramidal cells are found in the prefrontal cortex, the hippocampus, the entorhinal cortex, the olfactory cortex, and other areas. Dendrite arbors formed by apical dendrites are the means by which synaptic inputs into a cell are integrated. The apical dendrites in these regions contribute significantly to memory, learning, and sensory associations by modulating the excitatory and inhibitory signals received by the pyramidal cells.
Background
Two types of dendrites present on pyramidal cells are apical and basal dendrites. Apical dendrites are the most distal along the ascending trunk, and reside in layer 1. These distal apical dendrites receive synaptic input from related cortical as well as globally modulatory subcortical projections. Basal dendrites include shorter radially distributed dendrites which receive input from local pyramidal cells and interneurons. Pyramidal neurons segregate their inputs using proximal and apical dendrites.
Apical dendrites are studied in many ways. In cellular analysis, the electrical properties of the dendrite are studied using stimulus responses. A single surface shock of the cerebral cortex induces a 10–20 ms negative potential, a manifestation of the summed excitatory post-synaptic potentials
(EPSPs) evoked in
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https://en.wikipedia.org/wiki/Basal%20dendrite
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A basal dendrite is a dendrite that emerges from the base of a pyramidal cell that receives information from nearby neurons and passes it to the soma, or cell body. Due to their direct attachment to the cell body itself, basal dendrites are able to deliver strong depolarizing currents and therefore have a strong effect on action potential output in neurons. The physical characteristics of basal dendrites vary based on their location and species that they are found in. For example, the basal dendrites of humans are overall found to be the most intricate and spine-dense, as compared to other species such as Macaques. It is also observed that basal dendrites of the prefrontal cortex are larger and more complex in comparison to the smaller and simpler dendrites that can be seen within the visual cortex. Basal dendrites are capable of vast amounts of analog computing, which is responsible for many of the different nonlinear responses of modulating information in the neocortex. Basal dendrites additionally exist in dentate granule cells for a limited time before removal via regulatory factors. This removal usually occurs before the cell reaches adulthood, and is thought to be regulated through both intracellular and extracellular signals. Basal dendrites are part of the more overarching dendritic tree present on pyramidal neurons. They, along with apical dendrites, make up the part of the neuron that receives most of the electrical signaling. Basal dendrites have been found to be
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https://en.wikipedia.org/wiki/Oblique%20dendrite
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An oblique dendrite is a dendrite that branches from an apical dendrite that emerges from the apex of a pyramidal cell. Oblique dendrites typically branch one to two times before terminating. Dendrites are extensions of the cell body of a neuron.
Growth and development
The growth and development of oblique dendrites in rats has been linked to the type of environment, or condition, they are placed in. This is also known as environmental enrichment. The three types of conditions used in studies are an enriched conditioned, standard condition, and impoverished condition. The enriched condition contains mazes, an exercise wheel, other rats, and toys. The standard condition generally has a wheel for voluntary exercise and other rats. The impoverished condition only contains fellow rats.
Animals placed in an enriched environment had heavier, thicker cortexes and an increase in the number of dendritic branches (including oblique dendrites) in the hippocampus than the standard or impoverished condition. This phenomenon is known as neuroplasticity. Furthermore, the enriched condition may show in increase in monoamine neurotransmitter release such as serotonin and noradrenaline which have been linked to synaptic plasticity and learning. This is important because an increase in oblique dendrites and dendritic branching allows for increased neurotransmitter uptake. Environmental enrichment is crucial in early brain development due to increase formation of synapses, or synaptogenesis.
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https://en.wikipedia.org/wiki/Vapour%20phase%20decomposition
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Vapour phase decomposition (VPD) is a method used in the semiconductor industry to improve the sensitivity of total-reflection x-ray fluorescence spectroscopy by changing the contaminant from a thin layer (which has an angle-dependent fluorescence intensity in the TXRF-domain) to a granular residue. When using granular residue the limits of detection are improved because of a more intense fluorescence signal in angles smaller than the isokinetic angle.
Method
When using granular residue the limits of detection are improved because of a more intense fluorescence signal in angles smaller than the isokinetic angle. This can be achieved by enhancing the impurity concentration in the solution to be analyzed. In standard atomic absorption spectroscopy (AAS), the impurity is dissolved together with the matrix element. In VPD, the surface of the wafer is exposed to hydrofluoric acid vapour, which causes the surface oxide to dissolve together with the impurity metals. The acid droplets, condensed on the surface, are then analyzed using AAS.
Advantages
The method has yielded good results for the detection and measurement of nickel and iron. To improve the range of elemental impurities and lower detection limits, the acid droplets obtained from the silicon wafers are analyzed by ICP-MS (Inductively coupled plasma mass spectrometry). This technique, VPD ICP-MS provides accurate measurement of up to 60 elements and detection limits of in the range of 1E6-E10 atoms/sq.cm on the silicon
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https://en.wikipedia.org/wiki/Betz%20cell
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Betz cells (also known as pyramidal cells of Betz) are giant pyramidal cells (neurons) located within the fifth layer of the grey matter in the primary motor cortex. These neurons are the largest in the central nervous system, sometimes reaching 100 μm in diameter.
Betz cells are upper motor neurons that send their axons down to the spinal cord via the corticospinal tract, where in humans they synapse directly with anterior horn cells, which in turn synapse directly with their target muscles. Betz cells are not the sole source of direct connections to those neurons because most of the direct corticomotorneuronal cells are medium or small neurons. While Betz cells have one apical dendrite typical of pyramidal neurons, they have more primary dendritic shafts, which can branch out at almost any point from the soma (cell body). These perisomatic (around the cell body) and basal dendrites project into all cortical layers, but most of their horizontal branches/arbors populate layers V and VI, some reaching down into the white matter. According to one study, Betz cells represent about 10% of the total pyramidal cell population in layer Vb of the human primary motor cortex.
Betz cells are named after Ukrainian scientist Volodymyr Betz, who described them in his work published in 1874.
See also
List of distinct cell types in the adult human body
Notes
External links
NIF Search - Betz Cell via the Neuroscience Information Framework
Cerebral cortex
Human cells
Motor system
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https://en.wikipedia.org/wiki/Frisch%E2%80%93Waugh%E2%80%93Lovell%20theorem
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In econometrics, the Frisch–Waugh–Lovell (FWL) theorem is named after the econometricians Ragnar Frisch, Frederick V. Waugh, and Michael C. Lovell.
The Frisch–Waugh–Lovell theorem states that if the regression we are concerned with is expressed in terms of two separate sets of predictor variables:
where and are matrices, and are vectors (and is the error term), then the estimate of will be the same as the estimate of it from a modified regression of the form:
where projects onto the orthogonal complement of the image of the projection matrix . Equivalently, MX1 projects onto the orthogonal complement of the column space of X1. Specifically,
and this particular orthogonal projection matrix is known as the residual maker matrix or annihilator matrix.
The vector is the vector of residuals from regression of on the columns of .
The most relevant consequence of the theorem is that the parameters in do not apply to but to , that is: the part of uncorrelated with . This is the basis for understanding the contribution of each single variable to a multivariate regression (see, for instance, Ch. 13 in ).
The theorem also implies that the secondary regression used for obtaining is unnecessary when the predictor variables are uncorrelated: using projection matrices to make the explanatory variables orthogonal to each other will lead to the same results as running the regression with all non-orthogonal explanators included.
Moreover, the standard errors from the par
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https://en.wikipedia.org/wiki/Bayesian%20information%20criterion
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In statistics, the Bayesian information criterion (BIC) or Schwarz information criterion (also SIC, SBC, SBIC) is a criterion for model selection among a finite set of models; models with lower BIC are generally preferred. It is based, in part, on the likelihood function and it is closely related to the Akaike information criterion (AIC).
When fitting models, it is possible to increase the maximum likelihood by adding parameters, but doing so may result in overfitting. Both BIC and AIC attempt to resolve this problem by introducing a penalty term for the number of parameters in the model; the penalty term is larger in BIC than in AIC for sample sizes greater than 7.
The BIC was developed by Gideon E. Schwarz and published in a 1978 paper, where he gave a Bayesian argument for adopting it.
Definition
The BIC is formally defined as
where
= the maximized value of the likelihood function of the model , i.e. , where are the parameter values that maximize the likelihood function;
= the observed data;
= the number of data points in , the number of observations, or equivalently, the sample size;
= the number of parameters estimated by the model. For example, in multiple linear regression, the estimated parameters are the intercept, the slope parameters, and the constant variance of the errors; thus, .
Derivation
Konishi and Kitagawa derive the BIC to approximate the distribution of the data, integrating out the parameters using Laplace's method, starting with the follow
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https://en.wikipedia.org/wiki/Residual%20sum%20of%20squares
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In statistics, the residual sum of squares (RSS), also known as the sum of squared residuals (SSR) or the sum of squared estimate of errors (SSE), is the sum of the squares of residuals (deviations predicted from actual empirical values of data). It is a measure of the discrepancy between the data and an estimation model, such as a linear regression. A small RSS indicates a tight fit of the model to the data. It is used as an optimality criterion in parameter selection and model selection.
In general, total sum of squares = explained sum of squares + residual sum of squares. For a proof of this in the multivariate ordinary least squares (OLS) case, see partitioning in the general OLS model.
One explanatory variable
In a model with a single explanatory variable, RSS is given by:
where yi is the ith value of the variable to be predicted, xi is the ith value of the explanatory variable, and is the predicted value of yi (also termed ).
In a standard linear simple regression model, , where and are coefficients, y and x are the regressand and the regressor, respectively, and ε is the error term. The sum of squares of residuals is the sum of squares of ; that is
where is the estimated value of the constant term and is the estimated value of the slope coefficient .
Matrix expression for the OLS residual sum of squares
The general regression model with observations and explanators, the first of which is a constant unit vector whose coefficient is the regression int
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https://en.wikipedia.org/wiki/Explained%20sum%20of%20squares
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In statistics, the explained sum of squares (ESS), alternatively known as the model sum of squares or sum of squares due to regression (SSR – not to be confused with the residual sum of squares (RSS) or sum of squares of errors), is a quantity used in describing how well a model, often a regression model, represents the data being modelled. In particular, the explained sum of squares measures how much variation there is in the modelled values and this is compared to the total sum of squares (TSS), which measures how much variation there is in the observed data, and to the residual sum of squares, which measures the variation in the error between the observed data and modelled values.
Definition
The explained sum of squares (ESS) is the sum of the squares of the deviations of the predicted values from the mean value of a response variable, in a standard regression model — for example, , where yi is the i th observation of the response variable, xji is the i th observation of the j th explanatory variable, a and bj are coefficients, i indexes the observations from 1 to n, and εi is the i th value of the error term. In general, the greater the ESS, the better the estimated model performs.
If and are the estimated coefficients, then
is the i th predicted value of the response variable. The ESS is then:
where the value estimated by the regression line .
In some cases (see below): total sum of squares (TSS) = explained sum of squares (ESS) + residual sum of squares (RSS).
P
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https://en.wikipedia.org/wiki/Hydrospring
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A hydrospring or hydro-spring is a spring damped by hydraulic fluid (typically oil) being driven through holes in a piston, as the piston moves in response to a force. The spring is often made of rubber. Inside a rubber hydrospring there are hydraulic viscous damping systems which damp movement in all three directions but require very few parts. Even the slack adjustment may be integrated into the element.
Hydrosprings are used mainly as shock absorbers in applications such as damped suspension in railway bogies, bulldozer blade shock absorbers and as recoil absorbers for artillery.
See also
Dashpot
References
Army Dictionary - see hydrospring
Army Dictionary - see recoil cylinder
A railway hydrospring
Springs (mechanical)
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https://en.wikipedia.org/wiki/Optical%20parametric%20oscillator
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An optical parametric oscillator (OPO) is a parametric oscillator that oscillates at optical frequencies. It converts an input laser wave (called "pump") with frequency into two output waves of lower frequency () by means of second-order nonlinear optical interaction. The sum of the output waves' frequencies is equal to the input wave frequency: . For historical reasons, the two output waves are called "signal" and "idler", where the output wave with higher frequency is the "signal". A special case is the degenerate OPO, when the output frequency is one-half the pump frequency, , which can result in half-harmonic generation when signal and idler have the same polarization.
The first optical parametric oscillator was demonstrated by Joseph A. Giordmaine and Robert C. Miller in 1965, five years after the invention of the laser, at Bell Labs. Optical parametric oscillators are used as coherent light sources for various scientific purposes, and to generate squeezed light for quantum mechanics research. A Soviet report was also published in 1965.
Overview
The OPO consists essentially of an optical resonator and a nonlinear optical crystal. The optical resonator serves to resonate at least one of signal and idler waves. In the nonlinear optical crystal, the pump, signal and idler waves overlap. The interaction between these three waves leads to amplitude gain for signal and idler waves (parametric amplification) and a corresponding deamplification of the pump wave. The gain a
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https://en.wikipedia.org/wiki/Unit%20root%20test
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In statistics, a unit root test tests whether a time series variable is non-stationary and possesses a unit root. The null hypothesis is generally defined as the presence of a unit root and the alternative hypothesis is either stationarity, trend stationarity or explosive root depending on the test used.
General approach
In general, the approach to unit root testing implicitly assumes that the time series to be tested can be written as,
where,
is the deterministic component (trend, seasonal component, etc.)
is the stochastic component.
is the stationary error process.
The task of the test is to determine whether the stochastic component contains a unit root or is stationary.
Main tests
Other popular tests include:
augmented Dickey–Fuller test
this is valid in large samples.
Phillips–Perron test
KPSS test
here the null hypothesis is trend stationarity rather than the presence of a unit root.
ADF-GLS test
Unit root tests are closely linked to serial correlation tests. However, while all processes with a unit root will exhibit serial correlation, not all serially correlated time series will have a unit root. Popular serial correlation tests include:
Breusch–Godfrey test
Ljung–Box test
Durbin–Watson test
Notes
References
"2007 revision"
Time series statistical tests
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https://en.wikipedia.org/wiki/Dickey%E2%80%93Fuller%20test
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In statistics, the Dickey–Fuller test tests the null hypothesis that a unit root is present in an autoregressive (AR) time series model. The alternative hypothesis is different depending on which version of the test is used, but is usually stationarity or trend-stationarity. The test is named after the statisticians David Dickey and Wayne Fuller, who developed it in 1979.
Explanation
A simple AR model is
where is the variable of interest, is the time index, is a coefficient, and is the error term (assumed to be white noise). A unit root is present if . The model would be non-stationary in this case.
The regression model can be written as
where is the first difference operator and . This model can be estimated, and testing for a unit root is equivalent to testing . Since the test is done over the residual term rather than raw data, it is not possible to use standard t-distribution to provide critical values. Therefore, this statistic has a specific distribution simply known as the Dickey–Fuller table.
There are three main versions of the test:
1. Test for a unit root:
2. Test for a unit root with constant:
3. Test for a unit root with constant and deterministic time trend:
Each version of the test has its own critical value which depends on the size of the sample. In each case, the null hypothesis is that there is a unit root, . The tests have low statistical power in that they often cannot distinguish between true unit-root processes () and ne
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https://en.wikipedia.org/wiki/Roger%20Roche
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Roger Roche was a French political activist in Senegal. In 1925 he, along with two other persons, founded a cell of the French Communist Party in Rufisque. This was the first communist organisation in Senegal.
Later Roche left the party and joined the SFIO.
Year of birth missing
Year of death missing
People of French West Africa
Senegalese communists
French Section of the Workers' International politicians
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https://en.wikipedia.org/wiki/Don%20Brown%20%28voice%20actor%29
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Don Brown is a Canadian voice actor and comedian best known as the voice of Jaken in Inuyasha and Kurumazo in Kurozuka.
Voice roles
References
External links
Tony Valdez at CrystalAcids
Living people
20th-century Canadian male actors
21st-century Canadian male actors
Canadian male film actors
Canadian male television actors
Place of birth missing (living people)
Year of birth missing (living people)
Canadian male voice actors
Canadian impressionists (entertainers)
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https://en.wikipedia.org/wiki/Ch%C3%A9diak%E2%80%93Higashi%20syndrome
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Chédiak–Higashi syndrome (CHS) is a rare autosomal recessive disorder that arises from a mutation of a lysosomal trafficking regulator protein, which leads to a decrease in phagocytosis. The decrease in phagocytosis results in recurrent pyogenic infections, albinism, and peripheral neuropathy.
In Chédiak–Higashi syndrome, the lysosomal trafficking regulator (LYST) gene is mutated, leading to disruption of protein synthesis as well as the storage and secretory function of lysosomal granules in white blood cells. This results in defective white blood cell function with enlarged vesicles. This syndrome also leads to neutropenia and phagocyte bactericidal dysfunction due to impaired chemotaxis. Deficiency in serotonin and adenosine-phosphate-containing granules in platelets causes impaired platelet aggregation, leading to prolonged bleeding time. Thus, patients are susceptible to infections and often present with oculo-cutaneous albinism and coagulation defects. Patients often present with early-onset aggressive periodontitis associated with advanced alveolar bone loss and tooth mobility due to neutropenia and defective neutrophil function. Recurrent oral ulcerations are also one of the common oral manifestations in patients with this disease. Dental practitioners who notice child patients who present with recurrent unexplained gingivitis and periodontitis along with hypopigmentation of hair, skin and eyes should consider making a referral to medical practitioners to investigate
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https://en.wikipedia.org/wiki/Merna%20Kennedy
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Merna Kennedy (born Maude Kahler; September 7, 1908 – December 20, 1944) was an American actress of the late silent era and the transitional period into talkies.
Career
She was born in Kankakee, one of two children to Maud (née Reed) and John Kahler, a German-American butcher turned chiropractor. After her parents separated, her mother moved the family to California, where she married a grocer two years later, and changed their name to Kennedy. At the outbreak of World War I, their mother prepped seven-year-old Merna and brother Melvin (known as Merle) to tour as a dancing and singing sibling act on the Orpheum and Pantages theater circuits of vaudeville, where she became acquainted with Lita Grey. Merle broke his leg ending the duo, prompting Grey to suggest silent films to Merna.
Kennedy was best known during her brief career for her role opposite Charlie Chaplin in the silent film The Circus (1928), a role for which she was brought to the attention of Chaplin by her friend Lita Grey, who became Chaplin's second wife in 1924. She had red hair and muscular legs (due to being a dancer,) the latter of which helped her gain the role of the circus bareback rider.
Kennedy continued acting after The Circus, starring in early sound films, but retired in 1934 when she married choreographer/director Busby Berkeley on February 10, 1934 at Hollywood United Methodist Church. Their marriage broke up by 1936.
Death
Kennedy died at age 36 of a heart attack on December 20, 1944, four
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https://en.wikipedia.org/wiki/Lambda%20transition
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The λ (lambda) universality class is a group in condensed matter physics. It regroups several systems possessing strong analogies, namely, superfluids, superconductors and smectics (liquid crystals). All these systems are expected to belong to the same universality class for the thermodynamic critical properties of the phase transition. While these systems are quite different at the first glance, they all are described by similar formalisms and their typical phase diagrams are identical.
See also
Superfluid
Superconductor
Liquid crystal
Phase transition
Renormalization group
Topological defect
References
Books
Chaikin P. M. and Lubensky T. C. Principles of Condensed Matter Physics (Cambridge University Press, Cambridge) 1995, sect.9.
Feynman R. P. Progress in Low Temperature Physics Vol.1, edited by C. Gorter (North Holland, Amsterdam) 1955.
Journal articles
Translated as:
Condensed matter physics
Critical phenomena
Phase transitions
Phases of matter
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https://en.wikipedia.org/wiki/Tunica%20media
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The tunica media (Neo-Latin "middle coat"), or media for short, is the middle tunica (layer) of an artery or vein. It lies between the tunica intima on the inside and the tunica externa on the outside.
Artery
Tunica media is made up of smooth muscle cells, elastic tissue and collagen. It lies between the tunica intima on the inside and the tunica externa on the outside.
The middle coat (tunica media) is distinguished from the inner (tunica intima) by its color and by the transverse arrangement of its fibers.
In the smaller arteries it consists principally of smooth muscle fibers in fine bundles, arranged in lamellae and disposed circularly around the vessel. These lamellae vary in number according to the size of the vessel; the smallest arteries having only a single layer, and those slightly larger three or four layers - up to a maximum of six layers. It is to this coat that the thickness of the wall of the artery is mainly due.
In the larger arteries, as the iliac, femoral, and carotid, elastic fibers and collagen unite to form lamellae which alternate with the layers of smooth muscular fibers; these lamellae are united to one another by elastic fibers which pass between the smooth muscular bundles, and are connected with the fenestrated membrane of the inner coat.
In the largest arteries, as the aorta and brachiocephalic, the amount of elastic tissue is considerable; in these vessels a few bundles of white connective tissue also have been found in the middle coat. The
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https://en.wikipedia.org/wiki/Abswurmbachite
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Abswurmbachite is a copper manganese silicate mineral ((Cu,Mn2+)Mn3+6O8SiO4). It was first described in 1991 and named after Irmgard Abs-Wurmbach (born 1938), a German mineralogist. It crystallizes in the tetragonal system. Its Mohs scale rating is 6.5 and a specific gravity of 4.96. It has a metallic luster and its color is jet black, with light brown streaks.
See also
List of minerals
List of minerals named after people
References
Mindat.org - Abswurmbachite
Webmineral.com - Abswurmbachite
Handbook of Mineralogy - Abswurmbachite
Nesosilicates
Tetragonal minerals
Minerals in space group 142
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https://en.wikipedia.org/wiki/Helmholtz%20theorem%20%28classical%20mechanics%29
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The Helmholtz theorem of classical mechanics reads as follows:
Let be the Hamiltonian of a one-dimensional system, where is the kinetic energy and is a "U-shaped" potential energy profile which depends on a parameter .
Let denote the time average. Let
Then
Remarks
The thesis of this theorem of classical mechanics reads exactly as the heat theorem of thermodynamics. This fact shows that thermodynamic-like relations exist between certain mechanical quantities. This in turn allows to define the "thermodynamic state" of a one-dimensional mechanical system. In particular the temperature is given by time average of the kinetic energy, and the entropy by the logarithm of the action (i.e., ).
The importance of this theorem has been recognized by Ludwig Boltzmann who saw how to apply it to macroscopic systems (i.e. multidimensional systems), in order to provide a mechanical foundation of equilibrium thermodynamics. This research activity was strictly related to his formulation of the ergodic hypothesis.
A multidimensional version of the Helmholtz theorem, based on the ergodic theorem of George David Birkhoff is known as generalized Helmholtz theorem.
References
Helmholtz, H., von (1884a). Principien der Statik monocyklischer Systeme. Borchardt-Crelle’s Journal für die reine und angewandte Mathematik, 97, 111–140 (also in Wiedemann G. (Ed.) (1895) Wissenschafltliche Abhandlungen. Vol. 3 (pp. 142–162, 179–202). Leipzig: Johann Ambrosious Barth).
Helmholtz, H., von (1884b)
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https://en.wikipedia.org/wiki/Farkas%27%20lemma
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In mathematics, Farkas' lemma is a solvability theorem for a finite system of linear inequalities. It was originally proven by the Hungarian mathematician Gyula Farkas.
Farkas' lemma is the key result underpinning the linear programming duality and has played a central role in the development of mathematical optimization (alternatively, mathematical programming). It is used amongst other things in the proof of the Karush–Kuhn–Tucker theorem in nonlinear programming.
Remarkably, in the area of the foundations of quantum theory, the lemma also underlies the complete set of Bell inequalities in the form of necessary and sufficient conditions for the existence of a local hidden-variable theory, given data from any specific set of measurements.
Generalizations of the Farkas' lemma are about the solvability theorem for convex inequalities, i.e., infinite system of linear inequalities. Farkas' lemma belongs to a class of statements called "theorems of the alternative": a theorem stating that exactly one of two systems has a solution.
Statement of the lemma
There are a number of slightly different (but equivalent) formulations of the lemma in the literature. The one given here is due to Gale, Kuhn and Tucker (1951).
Here, the notation means that all components of the vector are nonnegative.
Example
Let , and The lemma says that exactly one of the following two statements must be true (depending on and ):
There exist , such that and , or
There exist such that , , and
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https://en.wikipedia.org/wiki/WSLI%20%28AM%29
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WSLI is a radio station which serves the Greater Grand Rapids, Michigan, area. The main broadcast frequency is 1480 kHz, which is licensed to Kentwood, Michigan, a Grand Rapids suburb. It broadcasts Smile FM's contemporary Christian music format.
History
Thr station went on the air December 11, 1954, as commercial station WMAX. By the late 1950s and early 1960s, it was the leading Top 40 music station in Grand Rapids. Afterward, the station played mostly middle of the road and adult contemporary music (and briefly used the WAFT calls for a time in the late 1960s/early 1970s), although WMAX did briefly return to a Top 40-style presentation from about 1972 to 1975 as "Good Max Music 1480". The station dropped its music format in January 1976 for a news/talk format. WMAX NewsRadio 1480 operated as a locally produced all-news radio format from 1976 to 1984, with a staff of 11 reporters. Later, the station dropped the news/talk format for gospel, then contemporary Christian music. For many years, WMAX was the Grand Rapids radio home for Detroit Red Wings hockey. WMAX changed transmitter locations (adding a directional night-time signal) and was reassigned from Grand Rapids to Kentwood in 1984.
The station went silent until July 4, 1991, when it became branded as "All-American NewsTalk 1480 WMAX". The AM station operated out of the Witte Travel Building at 3250 28th Street S.E., near Shaffer Avenue. The station simulcast the cable-TV network audio signal of CNN Headline News. At
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https://en.wikipedia.org/wiki/WGVU-FM
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WGVU-FM is an NPR member station serving Grand Rapids, Michigan. Owned by Grand Valley State University, it is simulcast in West Michigan. The main broadcast frequency is 88.5 MHz, which is licensed to Allendale, the Grand Rapids suburb that is home to Grand Valley State's main campus. It is simulcast on WGVS-FM 95.3 MHz, which is licensed to Whitehall and serves Muskegon. The format is Talk radio from NPR, along with jazz.
WGVU-FM began broadcasting on July 17, 1983, as WGVC-FM, owned by what was then Grand Valley State College. The station had originally operated (1974-1982) as student-run WSRX, with an alternative rock format. It was the first locally-focused NPR station in Grand Rapids. It was West Michigan's fourth full NPR member, joining WVGR, a repeater of WUOM-FM in Ann Arbor (now known as Michigan Radio), WMUK in Kalamazoo, and WBLV in Muskegon.
95.3 FM in Whitehall began as Top 40 station WLRQ ("Super Q") in the late 1970s. In the mid-1980s, the station bore the WRNF ("We're Rock Ninety Five") calls while continuing with a Top 40 format. By the mid-1990s, 95.3 FM had the WKBZ-FM calls and was airing an urban contemporary format as "Power 95.3". Station owners Robert Jewell and Daniel Thill donated WKBZ-FM, along with WKBZ (850 AM), to Grand Valley in 1995, but the following year the stations were sold to WLC Broadcasting, and it was not until November 1998 that WLC returned the stations to Grand Valley and the university began using them as simulcasts of
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https://en.wikipedia.org/wiki/Pallasite
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The pallasites are a class of stony–iron meteorite. They are relatively rare, and can be distinguished by the presence of large olivine crystal inclusions in the ferro-nickel matrix.
These crystals represent mantle and core material from differentiated planetesimals, which were destroyed by violent collisions during the early formation of the Solar System.
Structure and composition
It consists of centimetre-sized olivine crystals of peridot quality in an iron-nickel matrix. Coarser metal areas develop Widmanstätten patterns upon etching. Minor constituents are schreibersite, troilite, chromite, pyroxenes, and phosphates (whitlockite, stanfieldite, farringtonite, and merrillite).
Classification and subgroups
Using the oxygen isotopic composition, meteoric iron composition and silicate composition pallasites are divided into 4 subgroups:
Main group pallasites (PMG): Almost all pallasites
Eagle Station group (PES): 5 specimens known. They are related to IIF irons.
Pyroxene Pallasite grouplet (PPX): Counts only Vermillion and Yamato 8451. They take their name from the high orthopyroxene content (about 5%). Metal matrix shows a fine octahedrite Widmanstätten pattern.
Pallasite ungrouped (P-ung): Specimens that don't fit into any groups or grouplets
Origin
Pallasites were once thought to originate at the core-mantle boundary of differentiated asteroids that were subsequently shattered through impacts. An alternative recent hypothesis is that they are impact-generated mixtu
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https://en.wikipedia.org/wiki/Hemagglutinin%20esterase
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Hemagglutinin esterase (HEs) is a glycoprotein that certain enveloped viruses possess and use as an invading mechanism. HEs helps in the attachment and destruction of certain sialic acid receptors that are found on the host cell surface. Viruses that possess HEs include influenza C virus, toroviruses, and coronaviruses of the subgenus Embecovirus (which does not include SARS-like coronaviruses). HEs is a dimer transmembrane protein consisting of two monomers, each monomer is made of three domains. The three domains are: membrane fusion, esterase, and receptor binding domains.
The different HEs enzyme activities include: receptor binding activity, receptor hydrolysis (esterase) activity, and membrane fusion activity. The receptor binding activity involve the attachment of HEs to N-acetyl-9-O-acetylneuraminic acid (9-O-Ac- Neu5Ac) of glycolipids and glycoproteins and in turn serve as viral receptor. Receptor hydrolysis (esterase) activity allows virus particles to escape the infected cell by removing an acetyl group from the C9 position of terminal 9-O-Ac-Neu5Ac residues. Membrane fusion activity helps in incorporation viral genome into the host cell cytoplasm by enhancing the attachment between the viral envelope and host cell membrane.
In certain influenza viruses, the cell surface consists of both hemagglutinin (HA) and neuraminidase (NA) proteins that encompass enzymatic activities, whereas hemagglutinin-esterase fusion (HEF) proteins have been found to be the primary sin
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https://en.wikipedia.org/wiki/Dominic%20Purcell
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Dominic Haakon Myrtvedt Purcell (born 17 February 1970) is an Australian actor. He is best known for his portrayals of Lincoln Burrows in Fox's Prison Break (2005–2009; 2017), Mick Rory / Heat Wave in The CW's The Flash (2014–2016) and Legends of Tomorrow (2016–2021), as well as Drake / Dracula in Blade: Trinity (2004). He is also known for his role as Lewis "Lew" Brookbank in the 2004 film Three Way.
Early life
Purcell was born in Birkenhead, Cheshire (now Merseyside), England. He is the son of Phil Myrtvedt and Maureen (née Clarke) Purcell. His mother was Irish and his father was of Norwegian and English descent. In 1972, he and his family moved to Sydney, New South Wales, Australia, initially living in Bondi before settling in Penrith. He attended St Joseph’s Kingswood, St Finbar's Glenbrook primary School and Blaxland High School, as well as St Dominic's College and McCarthy Catholic College, Emu Plains. He later attended the Australian Theatre for Young People and then enrolled at the Western Australian Academy of Performing Arts, where he studied with Hugh Jackman. He holds triple British-Irish-Australian citizenship, being British by virtue of being born in the United Kingdom before the country abolished unconditional birthright citizenship in 1983 and being Irish automatically through his Irish mother.
Personal life
Purcell was married to Rebecca Williamson from 1998 until 2008, during which time the couple had four children.
In 2011, Purcell started dating former
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https://en.wikipedia.org/wiki/John%20Hughes%20%28footballer%2C%20born%201943%29
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John Hughes (3 April 1943 – 1 August 2022) was a Scottish footballer who played for Celtic, Crystal Palace, Sunderland and the Scotland national team. Hughes was nicknamed 'Yogi', derived from the popular cartoon character Yogi Bear, said to be due to his large build. He was part of the Celtic team that won the 1966–67 European Cup although he did not play in the final due to injury.
Club career
Born in Coatbridge, Hughes signed for Celtic from Shotts Bon Accord in 1959, and scored 197 goals in 435 appearances during his eleven seasons with the club.
He was part of the Celtic squad who won the European Cup in 1967 and became known as the 'Lisbon Lions'. Although Hughes was not in the side that won the final, he was awarded a winner's medal because he had played in the requisite number of matches to qualify for a medal, as had Joe McBride and Charlie Gallagher.
Celtic reached the European Cup final for the second time in 1970, after they defeated English champions Leeds United in both legs of the semi-final. In the first leg, Celtic beat Leeds 1–0 at Elland Road with a goal from George Connelly. The second leg, which was played at Hampden Park in front of almost 140,000 people, was won 2–1 by Celtic. Hughes scored Celtic's first goal in that match, after Billy Bremner had given Leeds an early lead and levelled the aggregate score. Celtic lost the final 2–1 after extra time to Dutch side Feyenoord, with Hughes playing the whole game. Despite playing primarily on the wing, Hu
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https://en.wikipedia.org/wiki/Multiple%20Spanning%20Tree%20Protocol
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The Multiple Spanning Tree Protocol (MSTP) and algorithm, provides both simple and full connectivity assigned to any given virtual LAN (VLAN) throughout a bridged local area network. MSTP uses bridge protocol data unit (BPDUs) to exchange information between spanning-tree compatible devices, to prevent loops in each Multiple Spanning Tree instance (MSTI) and in the common and internal spanning tree (CIST), by selecting active and blocked paths. This is done as well as in Spanning Tree Protocol (STP) without the need of manually enabling backup links and getting rid of switching loop danger.
Moreover, MSTP allows frames/packets assigned to different VLANs to follow separate paths, each based on an independent MSTI, within MST regions composed of local area networks (LANs) and MST bridges. These regions and the other bridges and LANs are connected into a single common spanning tree (CST).
History and motivation
It was originally defined in IEEE 802.1s as an amendment to 802.1Q, 1998 edition and later merged into IEEE 802.1Q-2005 Standard, clearly defines an extension or an evolution of Radia Perlman's Spanning Tree Protocol (STP) and the Rapid Spanning Tree Protocol (RSTP). It has some similarities with Cisco Systems' Multiple Instances Spanning Tree Protocol (MISTP), but there are some differences.
The original STP and RSTP work on the physical link level, preventing bridge loops when redundant paths are present. However, when a LAN is virtualized using VLAN trunking, ea
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https://en.wikipedia.org/wiki/Cell%20plate
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Cytokinesis in terrestrial plants occurs by cell plate formation. This process entails the delivery of Golgi-derived and endosomal vesicles carrying cell wall and cell membrane components to the plane of cell division and the subsequent fusion of these vesicles within this plate.
After formation of an early tubulo-vesicular network at the center of the cell, the initially labile cell plate consolidates into a tubular network and eventually a fenestrated sheet. The cell plate grows outward from the center of the cell to the parental plasma membrane with which it will fuse, thus completing cell division. Formation and growth of the cell plate is dependent upon the phragmoplast, which is required for proper targeting of Golgi-derived vesicles to the cell plate.
As the cell plate matures in the central part of the cell, the phragmoplast disassembles in this region and new elements are added on its outside. This process leads to a steady expansion of the phragmoplast and, concomitantly, to a continuous retargeting of Golgi-derived vesicles to the growing edge of the cell plate. Once the cell plate reaches and fuses with the plasma membrane the phragmoplast disappears. This event not only marks the separation of the two daughter cells, but also initiates a range of biochemical modifications that transform the callose-rich, flexible cell plate into a cellulose-rich, stiff primary cell wall.
The heavy dependence of cell plate formation on active Golgi stacks explains why plant c
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https://en.wikipedia.org/wiki/Advantest
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is a Japanese leading manufacturer of automatic test equipment (ATE) for the semiconductor industry, and a manufacturer of measuring instruments used in the design, production and maintenance of electronic systems including fiber optic and wireless communications equipment and digital consumer products. Based in Tokyo, Advantest produces Memory, SoC and RF test systems.
History
Advantest was founded in Japan in 1954 as Takeda Riken Industry Co., Ltd., and was a maker of electronic measuring instruments. The company entered the semiconductor testing business in 1972, began trading on the Tokyo Stock Exchange in 1983 and changed its name to Advantest Corporation in 1985. The company’s stock began trading on the New York Stock Exchange in 2001.
Expanding its semiconductor test business, Advantest established its North American subsidiary, Advantest America, in 1982, and its European operations in Munich in 1983, to locate its sales and service operations closer to its North American and European customers. The company also has subsidiaries throughout Asia and operates in 18 countries. With the integration with Verigy completed, the company currently has approximately 6,464 employees worldwide.
In 2002, Advantest was one of the founding member companies that established the Semiconductor Test Consortium (STC)—the first international, industry-wide collaboration aimed at developing a highly scalable, flexible test platform to reduce the cost of test of SoCs and other advance
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https://en.wikipedia.org/wiki/Methyl%20red
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Methyl red (2-(N,N-dimethyl-4-aminophenyl) azobenzenecarboxylic acid), also called C.I. Acid Red 2, is an indicator dye that turns red in acidic solutions. It is an azo dye, and is a dark red crystalline powder. Methyl red is a pH indicator; it is red in pH under 4.4, yellow in pH over 6.2, and orange in between, with a pKa of 5.1. Murexide and methyl red are investigated as promising enhancers of sonochemical destruction of chlorinated hydrocarbon pollutants. Methyl red is classed by the IARC in group 3 - unclassified as to carcinogenic potential in humans.
Preparation
As an azo dye, methyl red may be prepared by diazotization of anthranilic acid, followed by reaction with dimethylaniline:
Properties
Methyl red displays pH dependent photochromism, with protonation causing it to adopt a hydrazone/quinone structure.
Methyl Red has a special use in histopathology for showing acidic nature of tissue and presence of organisms with acidic natured cell walls.
Methyl Red is detectably fluorescent in 1:1 water:methanol (pH 7.0), with an emission maximum at 375 nm (UVA) upon excitation with 310 nm light (UVB).
Methyl red test
In microbiology, methyl red is used in the methyl red test (MR test), used to identify bacteria producing stable acids by mechanisms of mixed acid fermentation of glucose (cf. Voges–Proskauer test).
The MR test, the "M" portion of the four IMViC tests, is used to identify enteric bacteria based on their pattern of glucose metabolism. All enterics initially
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https://en.wikipedia.org/wiki/Roger%20Boisjoly
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Roger Mark Boisjoly ( ,; April 25, 1938 – January 6, 2012) was an American mechanical engineer, fluid dynamicist, and an aerodynamicist. He is best known for having raised strenuous objections to the launch of the Space Shuttle Challenger months before the loss of the spacecraft and its crew in January 1986. Boisjoly correctly predicted, based on earlier flight data, that the O-rings on the rocket boosters would fail if the shuttle launched in cold weather. Morton Thiokol's managers decided to launch the shuttle despite his warnings, leading to the catastrophic failure. He was considered a high-profile whistleblower.
Early life and education
Boisjoly was born on April 25, 1938, in the city of Lowell, Massachusetts. He grew up in the neighborhood of Belvedere as the son of a mill worker and one of three brothers. During high-school he played tennis.
Boisjoly studied mechanical engineering at the University of Massachusetts Lowell.
Career
Boisjoly started his career at a used-aircraft company in western Massachusetts, before moving to California for work. He subsequently worked for companies in California on lunar module life-support systems and the moon vehicle. He later worked for Morton Thiokol, the manufacturer of the solid rocket boosters (SRBs) for the Space Shuttle program.
O-ring safety concerns
Boisjoly wrote a memo in July 1985 to his superiors concerning the faulty design of the solid rocket boosters that, if left unaddressed, could lead to a catastrophic even
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https://en.wikipedia.org/wiki/Cyanuric%20chloride
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Cyanuric chloride is an organic compound with the formula (NCCl)3. This white solid is the chlorinated derivative of 1,3,5-triazine. It is the trimer of cyanogen chloride. Cyanuric chloride is the main precursor to the popular but controversial herbicide atrazine.
Production
Cyanuric chloride is prepared in two steps from hydrogen cyanide via the intermediacy of cyanogen chloride, which is trimerized at elevated temperatures over a carbon catalyst:
HCN + Cl2 → ClCN + HCl
In 2005, approximately 200,000 tons were produced.
Industrial uses
It is estimated that 70% of cyanuric chloride is used in the preparation of the triazine-class pesticides, especially atrazine. Such reactions rely on the easy displacement of the chloride with nucleophiles such as amines:
(ClCN)3 + 2 RNH2 → (RNHCN)(ClCN)2 + RNH3+Cl−
Other triazine herbicides, such as simazine, anilazine and cyromazine are made in an analogous way.
Cyanuric chloride is also used as a precursor to dyes and crosslinking agents. The largest class of these dyes are the sulfonated triazine-stilbene optical brighteners (OBA) or fluorescent whitening agents (FWA) commonly found in detergent formulas and white paper. Many reactive dyes also incorporate a triazine ring. They are also manufactured by way of the chloride displacement reaction shown above.
Organic synthesis
In one specialized application, cyanuric chloride is employed as a reagent in organic synthesis for the conversion of carboxylic acids into acyl c
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https://en.wikipedia.org/wiki/Algorithmic%20trading
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Algorithmic trading is a method of executing orders using automated pre-programmed trading instructions accounting for variables such as time, price, and volume. This type of trading attempts to leverage the speed and computational resources of computers relative to human traders. In the twenty-first century, algorithmic trading has been gaining traction with both retail and institutional traders. A study in 2019 showed that around 92% of trading in the Forex market was performed by trading algorithms rather than humans.
It is widely used by investment banks, pension funds, mutual funds, and hedge funds that may need to spread out the execution of a larger order or perform trades too fast for human traders to react to. However, it is also available to private traders using simple retail tools.
The term algorithmic trading is often used synonymously with automated trading system. These encompass a variety of trading strategies, some of which are based on formulas and results from mathematical finance, and often rely on specialized software.
Examples of strategies used in algorithmic trading include systematic trading, market making, inter-market spreading, arbitrage, or pure speculation, such as trend following. Many fall into the category of high-frequency trading (HFT), which is characterized by high turnover and high order-to-trade ratios. HFT strategies utilize computers that make elaborate decisions to initiate orders based on information that is received electronical
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https://en.wikipedia.org/wiki/BNPP
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BNPP may refer to:
Bataan Nuclear Power Plant
Belarusian Nuclear Power Plant
Barisan Nasional Pembebasan Patani
BNP Paribas
bis (p-nitrophenyl)phosphate, an enzyme inhibitor of the organophosphate class
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https://en.wikipedia.org/wiki/Exact%20test
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In statistics, an exact (significance) test is a test such that if the null hypothesis is true, then all assumptions made during the derivation of the distribution of the test statistic are met. Using an exact test provides a significance test that maintains the type I error rate of the test () at the desired significance level of the test. For example, an exact test at a significance level of , when repeated over many samples where the null hypothesis is true, will reject at most of the time. This is in contrast to an approximate test in which the desired type I error rate is only approximately maintained (i.e.: the test might reject > 5% of the time), while this approximation may be made as close to as desired by making the sample size sufficiently large.
Exact tests that are based on discrete test statistics may be conservative, indicating that the actual rejection rate lies below the nominal significance level . As an example, this is the case for Fisher's exact test and its more powerful alternative, Boschloo's test. If the test statistic is continuous, it will reach the significance level exactly.
Parametric tests, such as those used in exact statistics, are exact tests when the parametric assumptions are fully met, but in practice, the use of the term exact (significance) test is reserved for non-parametric tests, i.e., tests that do not rest on parametric assumptions. However, in practice, most implementations of non-parametric test software use asymptotical alg
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https://en.wikipedia.org/wiki/Stochastic%20drift
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In probability theory, stochastic drift is the change of the average value of a stochastic (random) process. A related concept is the drift rate, which is the rate at which the average changes. For example, a process that counts the number of heads in a series of fair coin tosses has a drift rate of 1/2 per toss. This is in contrast to the random fluctuations about this average value. The stochastic mean of that coin-toss process is 1/2 and the drift rate of the stochastic mean is 0, assuming 1 = heads and 0 = tails.
Stochastic drifts in population studies
Longitudinal studies of secular events are frequently conceptualized as consisting of a trend component fitted by a polynomial, a cyclical component often fitted by an analysis based on autocorrelations or on a Fourier series, and a random component (stochastic drift) to be removed.
In the course of the time series analysis, identification of cyclical and stochastic drift components is often attempted by alternating autocorrelation analysis and differencing of the trend. Autocorrelation analysis helps to identify the correct phase of the fitted model while the successive differencing transforms the stochastic drift component into white noise.
Stochastic drift can also occur in population genetics where it is known as genetic drift. A finite population of randomly reproducing organisms would experience changes from generation to generation in the frequencies of the different genotypes. This may lead to the fixation of
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https://en.wikipedia.org/wiki/Dentate%20nucleus
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The dentate nucleus is a cluster of neurons, or nerve cells, in the central nervous system that has a dentate – tooth-like or serrated – edge. It is located within the deep white matter of each cerebellar hemisphere, and it is the largest single structure linking the cerebellum to the rest of the brain. It is the largest and most lateral, or farthest from the midline, of the four pairs of deep cerebellar nuclei, the others being the globose and emboliform nuclei, which together are referred to as the interposed nucleus, and the fastigial nucleus. The dentate nucleus is responsible for the planning, initiation and control of voluntary movements. The dorsal region of the dentate nucleus contains output channels involved in motor function, which is the movement of skeletal muscle, while the ventral region contains output channels involved in nonmotor function, such as conscious thought and visuospatial function.
Development
The dentate nucleus is highly convoluted, with gyri (ridges on the cerebral cortex) and sulci (furrows or grooves on the cerebral cortex). Its formation is coincident with a critical period of extensive growth in the fetal dentate. The dentate nucleus becomes visible in the cerebellar white matter as early as 11–12 weeks of gestation, containing only smooth lateral (towards the side(s) or away from the midline) and medial (towards the midline) surfaces. During this time, the neurons of the dentate nucleus are similar in shape and form, being mainly bipolar
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https://en.wikipedia.org/wiki/Stellate%20cell
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Stellate cells are neurons in the central nervous system, named for their star-like shape formed by dendritic processes radiating from the cell body. Many stellate cells are GABAergic and are located in the molecular layer of the cerebellum. Stellate cells are derived from dividing progenitor cells in the white matter of postnatal cerebellum. Dendritic trees can vary between neurons. There are two types of dendritic trees in the cerebral cortex, which include pyramidal cells, which are pyramid shaped and stellate cells which are star shaped. Dendrites can also aid neuron classification. Dendrites with spines are classified as spiny, those without spines are classified as aspinous. Stellate cells can be spiny or aspinous, while pyramidal cells are always spiny. Most common stellate cells are the inhibitory interneurons found within the upper half of the molecular layer in the cerebellum. Cerebellar stellate cells synapse onto the dendritic trees of Purkinje cells and send inhibitory signals. Stellate neurons are sometimes found in other locations in the central nervous system; cortical spiny stellate cells are found in layer IVC of the primary visual cortex. In the somatosensory barrel cortex of mice and rats, glutamatergic (excitatory) spiny stellate cells are organized in the barrels of layer 4. They receive excitatory synaptic fibres from the thalamus and process feed forward excitation to 2/3 layer of the primary visual cortex to pyramidal cells. Cortical spiny stellate c
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https://en.wikipedia.org/wiki/Golgi%20cell
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In neuroscience, Golgi cells are inhibitory interneurons found within the granular layer of the cerebellum. They were first identified as inhibitory in 1964.
It was also the first example of an inhibitory feedback network, where the inhibitory interneuron was identified anatomically.
These cells synapse onto the dendrite of granule cells and unipolar brush cells. They receive excitatory input from mossy fibres, also synapsing on granule cells, and parallel fibers, which are long granule cell axons. Thereby this circuitry allows for feed-forward and feed-back inhibition of granule cells.
The main synapse made by these cells is a synapse onto the mossy fibre - granule cell excitatory synapse in a glomerulus. The glomerulus is made up of the mossy fibre terminal, granule cell dendrites, the Golgi terminal and is enclosed by a glial coat.
The Golgi cell acts by altering the mossy fibre - granule cell synapse.
The Golgi cells use GABA as their neurotransmitter. The basal level of GABA produces a postsynaptic leak conductance by tonically activating alpha 6-containing GABA-A receptors on the granule cell.
These high-affinity receptors are located both synaptically and extrasynaptically on the granule cell. The synaptic receptors mediate phasic contraction, duration of around 20-30ms whereas the extrasynapatic receptors mediate tonic inhibition of around 200ms, and are activated by synapse spill over.
Additionally the GABA acts on GABA-B receptors which are located presynaptica
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https://en.wikipedia.org/wiki/Murray%20Barr
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Murray Llewellyn Barr (June 20, 1908 – May 4, 1995) was a Canadian physician and medical researcher who discovered with graduate student Ewart George Bertram, in 1948, an important cell structure, the "Barr body".
Born in Belmont, Ontario, he was educated at the University of Western Ontario, where he received his Bachelor of Arts in 1930, M.D. in 1933, and Master of Science in 1938. He was an RCAF wing commander between 1939 and 1945. From 1936 to 1977, he served as a faculty member at the University of Western Ontario. He was a member of The Harvey Club of London, the oldest medical club in Canada, which consisted of other noteworthy physicians in southwestern Ontario, and was loosely associated with the University of Western Ontario.
In 1955, he collaborated with K.L. Moore to introduce a buccal smear test. This test used cells rubbed from the lining of the mouth to identify individuals with abnormal numbers of sex-chromosome bodies, thereby determining whether they had errors in their sex-chromosome complex. Karyotyping and chromosome studies were then used to study these errors further. This research provided a major advancement in understanding the cause of various congenital syndromes.
Murray Barr published two books, The Human Nervous System and A Century of Medicine at Western. "The Human Nervous System" was used as the primary neuroanatomy textbook by medical students for several years.
He was nominated for the Nobel Prize in Physiology or Medicine.
In 1968, h
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https://en.wikipedia.org/wiki/Hokku
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is the opening stanza of a Japanese orthodox collaborative linked poem, renga, or of its later derivative, renku (haikai no renga). From the time of Matsuo Bashō (1644–1694), the hokku began to appear as an independent poem, and was also incorporated in haibun (in combination with prose). In the late 19th century, Masaoka Shiki (1867–1902) renamed the standalone hokku as "haiku", and the latter term is now generally applied retrospectively to all hokku appearing independently of renku or renga, irrespective of when they were written. The term hokku continues to be used in its original sense, as the opening verse of a linked poem.
Content
Within the traditions of renga and renku, the hokku, as the opening verse of the poem, has always held a special position. It was traditional for the most honoured guest at the poetry-writing session to be invited to compose it and he would be expected to offer praise to his host and/or deprecate himself (often symbolically) while superficially referring to current surroundings and seasons. (The following verse fell to the host, who would then respond with a compliment to the guest, again, usually symbolically).
Form
Typically, a hokku is 17 moras (or on) in length, composed of three metrical units of 5, 7 and 5 moras respectively. Alone among the verses of a poem, the hokku includes a kireji or "cutting-word" that appears at the end of one of its three metrical units. Like all of the other stanzas, a Japanese hokku is traditionally writt
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https://en.wikipedia.org/wiki/Anserine
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Anserine (β-alanyl-3-methylhistidine) is a dipeptide containing β-alanine and 3-methylhistidine. Anserine is a derivative of carnosine, which has been methylated.
Both anserine and carnosine chelate copper. Due to its methylation, anserine is more stable in serum and resistant to degradation than carnosine. Anserine can be found in the skeletal muscle and brain of mammals and birds.
The pKa of the imidazole ring of histidine, when contained in anserine, is 7.04.
Neuroprotective effects
An animal model study of Alzheimer's disease using mice found that treatment with anserine reduced memory loss. Anserine reduced glial inflammatory activity (particularly of astrocyte). The study also found that anserine-treated mice had greater pericyte surface area. The greater area of pericytes was commensurate with improved memory (pericytes wrap around brain capillary to control blood flow and gate cells from neurotoxin, blocking inflammation). The anserine-treated mice overall performed better on a spatial memory test (Morris Water Maze).
A human study on 84 elderly subjects showed that subjects who took anserine and carnosine supplements for one year showed increased blood flow in the prefrontal cortex on MRI.
A study demonstrated that the free N-terminal of histidine on anserine and carnosine protect against zinc-caused neurotoxicity and regulate the Arc pathway in which Arc protein is used to produce dendrite protein for connecting nerve cells.
Both Anserine and Carnosine are
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https://en.wikipedia.org/wiki/DNA%20mismatch%20repair
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DNA mismatch repair (MMR) is a system for recognizing and repairing erroneous insertion, deletion, and mis-incorporation of bases that can arise during DNA replication and recombination, as well as repairing some forms of DNA damage.
Mismatch repair is strand-specific. During DNA synthesis the newly synthesised (daughter) strand will commonly include errors. In order to begin repair, the mismatch repair machinery distinguishes the newly synthesised strand from the template (parental). In gram-negative bacteria, transient hemimethylation distinguishes the strands (the parental is methylated and daughter is not). However, in other prokaryotes and eukaryotes, the exact mechanism is not clear. It is suspected that, in eukaryotes, newly synthesized lagging-strand DNA transiently contains nicks (before being sealed by DNA ligase) and provides a signal that directs mismatch proofreading systems to the appropriate strand. This implies that these nicks must be present in the leading strand, and evidence for this has recently been found.
Recent work has shown that nicks are sites for RFC-dependent loading of the replication sliding clamp, proliferating cell nuclear antigen (PCNA), in an orientation-specific manner, such that one face of the donut-shape protein is juxtaposed toward the 3'-OH end at the nick. Loaded PCNA then directs the action of the MutLalpha endonuclease to the daughter strand in the presence of a mismatch and MutSalpha or MutSbeta.
Any mutational event that dis
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https://en.wikipedia.org/wiki/ORTF%20stereo%20technique
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The ORTF stereo technique, also known as side-other-side, is a microphone technique used to record stereo sound.
It was devised around 1960 at the Office de Radiodiffusion Télévision Française
(ORTF), currently Radio France.
ORTF combines both the volume difference and the timing difference as sound arrives on- and off-axis at two cardioid microphones spread to a 110° angle, and spaced 17 cm apart.
The microphones should be as similar as possible, preferably a frequency-matched pair of an identical type and model.
The result is a realistic stereo field that has reasonable compatibility with mono playback. Since the cardioid polar pattern rejects off-axis sound, less of the ambient room characteristics are picked up. This means that the mics can be placed farther away from the sound sources, resulting in a blend that may be more appealing. Further, the availability of purpose-built microphone mounts makes ORTF easy to achieve.
As with all microphone arrangements, the spacing and angle can be manually adjusted slightly by ear for the best sound, which may vary depending on room acoustics, source characteristics, and other factors. But this arrangement is defined as it is because it was the result of considerable research and experimentation, and its results are predictable and repeatable.
These interchannel differences are not the same as interaural differences, as produced by artificial head recordings. Even the spacing of 17 cm is not strictly based on interaural ear s
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https://en.wikipedia.org/wiki/Base%20excision%20repair
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Base excision repair (BER) is a cellular mechanism, studied in the fields of biochemistry and genetics, that repairs damaged DNA throughout the cell cycle. It is responsible primarily for removing small, non-helix-distorting base lesions from the genome. The related nucleotide excision repair pathway repairs bulky helix-distorting lesions. BER is important for removing damaged bases that could otherwise cause mutations by mispairing or lead to breaks in DNA during replication. BER is initiated by DNA glycosylases, which recognize and remove specific damaged or inappropriate bases, forming AP sites. These are then cleaved by an AP endonuclease. The resulting single-strand break can then be processed by either short-patch (where a single nucleotide is replaced) or long-patch BER (where 2–10 new nucleotides are synthesized).
Lesions processed by BER
Single bases in DNA can be chemically damaged by a variety of mechanisms, the most common ones being deamination, oxidation, and alkylation. These modifications can affect the ability of the base to hydrogen-bond, resulting in incorrect base-pairing, and, as a consequence, mutations in the DNA. For example, incorporation of adenine across from 8-oxoguanine (right) during DNA replication causes a G:C base pair to be mutated to T:A. Other examples of base lesions repaired by BER include:
Oxidized bases: 8-oxoguanine, 2,6-diamino-4-hydroxy-5-formamidopyrimidine (FapyG, FapyA)
Alkylated bases: 3-methyladenine, 7-methylguanosin
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https://en.wikipedia.org/wiki/Media%20in%20Omaha%2C%20Nebraska
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This is a list of media serving the Omaha metropolitan area in Omaha, Nebraska and Council Bluffs, Iowa.
Radio
Start dates are for the frequency/station license, not for callsign or programming that may have moved from license to license.
Omaha radio stations gets 25 Analog FM stations, 10 Digital HD Radio FM stations including 9 subchannels Like HD-2 and HD-3, 11 Analog AM stations, and 1 Digital HD Radio AM Station affiliated KFAB.
AM
FM
Television
Omaha TV stations gets 8 full-powered Digital channels including 29 subchannels and 1 low-powered Digital channel including 2 subchannels.
Print
The Omaha World-Herald, the Omaha Bee, and by 1900 the Omaha Daily News had developed into the city's most influential journals.
The African American community in Omaha has had several newspapers serve it. The first was the Progress, established in 1889 by Ferdinand L. Barnett. Cyrus D. Bell, an ex-slave, established the Afro-American Sentinel in 1892. In 1893 George F. Franklin started publishing the Enterprise, later published by Thomas P. Mahammitt. It was the longest lived of any of the early African American newspapers published in Omaha. The best known and most widely read of all African American newspapers in the city was the Omaha Monitor, established in 1915, edited and published by Reverend John Albert Williams. It stopped being published in 1929. In 1906, Lucille Skaggs Edwards published, The Women's Aurora, making her the first black woman to publish a magazine in Neb
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https://en.wikipedia.org/wiki/Endoreduplication
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Endoreduplication (also referred to as endoreplication or endocycling) is replication of the nuclear genome in the absence of mitosis, which leads to elevated nuclear gene content and polyploidy. Endoreplication can be understood simply as a variant form of the mitotic cell cycle (G1-S-G2-M) in which mitosis is circumvented entirely, due to modulation of cyclin-dependent kinase (CDK) activity. Examples of endoreplication characterized in arthropod, mammalian, and plant species suggest that it is a universal developmental mechanism responsible for the differentiation and morphogenesis of cell types that fulfill an array of biological functions. While endoreplication is often limited to specific cell types in animals, it is considerably more widespread in plants, such that polyploidy can be detected in the majority of plant tissues.
Examples in nature
Endoreplicating cell types that have been studied extensively in model organisms
Endoreplication, endomitosis and polytenization
Endoreplication, endomitosis and polytenization are three somewhat different processes resulting in polyploidization of a cell in a regulated manner. In endoreplication cells skip M phase completely, resulting in a mononucleated polyploid cell. Endomitosis is a type of cell cycle variation where mitosis is initiated, but some of the processes are not completed. Depending on how far the cell progresses through mitosis, this will give rise to a mononucleated or binucleated polyploid cell. Polytenization
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https://en.wikipedia.org/wiki/Aerinite
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Aerinite () is a bluish-purple inosilicate mineral. It crystallizes in the monoclinic system and occurs as fibrous or compact masses and coatings. It has a dark, vitreous luster, a specific gravity of 2.48 and a Mohs hardness of 3.
It is a low-temperature hydrothermal phase occurring in zeolite facies alteration of dolerites. Associated minerals include prehnite, scolecite and mesolite.
Its name comes from a Greek root "aerinos," meaning "atmosphere" or "sky blue". It was first described by Lasaulx (1876) from a specimen in the Wroclaw museum that was obtained in Aragon, Spain. In 1882, the geologist Luis Mariano Vidal found the mineral in situ in Caserras del Castillo, a locality that currently belongs to the municipality of Estopiñán del Castillo, in Huesca (Spain).
Deposits and uses
Aerinite is a rare mineral. It has been found in several deposits in the Spanish Pyrenees of Huesca and Lleida, as in Estopiñán del Castillo, Camporrells, Juseu and Tartareu. In France, the site is important from St. Pendelon, in the Landes. Aerinite was used as a blue pigment in Romanesque paintings in many churches in the Spain, and also in some French, including the most famous of them, the Pantocrator in the church of San Clemente de Tahull.
See also
List of minerals
References
Calcium minerals
Iron minerals
Magnesium minerals
Inosilicates
Carbonate minerals
Trigonal minerals
Minerals in space group 158
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https://en.wikipedia.org/wiki/Aerugite
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Aerugite is a rare complex nickel arsenate mineral with a variably reported formula: Ni9(AsO4)2AsO6. It forms green to deep blue-green trigonal crystals. It has a Mohs hardness of 4 and a specific gravity of 5.85 to 5.95.
It was first described in 1858 in either the South Terres mine of Cornwall, England or in the Ore Mountains, Saxony, Germany. The origin is disputed. The most common occurrence is as an incrustation on furnace walls in which ores are roasted. Its name comes from the Latin word aerugo for copper rust.
See also
List of minerals
References
Nickel minerals
Arsenate minerals
Trigonal minerals
Minerals in space group 166
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https://en.wikipedia.org/wiki/Restriction%20site
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Restriction sites, or restriction recognition sites, are located on a DNA molecule containing specific (4-8 base pairs in length) sequences of nucleotides, which are recognized by restriction enzymes. These are generally palindromic sequences (because restriction enzymes usually bind as homodimers), and a particular restriction enzyme may cut the sequence between two nucleotides within its recognition site, or somewhere nearby.
Function
For example, the common restriction enzyme EcoRI recognizes the palindromic sequence GAATTC and cuts between the G and the A on both the top and bottom strands. This leaves an overhang (an end-portion of a DNA strand with no attached complement) known as a sticky end on each end of AATT. The overhang can then be used to ligate in (see DNA ligase) a piece of DNA with a complementary overhang (another EcoRI-cut piece, for example).
Some restriction enzymes cut DNA at a restriction site in a manner which leaves no overhang, called a blunt end. Blunt ends are much less likely to be ligated by a DNA ligase because the blunt end doesn't have the overhanging base pair that the enzyme can recognize and match with a complementary pair. Sticky ends of DNA however are more likely to successfully bind with the help of a DNA ligase because of the exposed and unpaired nucleotides. For example, a sticky end trailing with AATTG is more likely to bind with a ligase than a blunt end where both the 5' and 3' DNA strands are paired. In the case of the example
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https://en.wikipedia.org/wiki/PortalPlayer
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PortalPlayer, founded in 1999, was a fabless semiconductor company that supplied system-on-a-chip semiconductors, firmware and software for personal media players. The company handled semiconductor design and firmware development, while subcontracting the actual semiconductor manufacturing to merchant foundries.
It gained recognition as the company with which Apple contracted for development of the original iPod. The company went public with an IPO in November 2004 and traded on the NASDAQ under ticker symbol PLAY. Sales to Apple grew to 90% of the company's gross revenue, which ultimately hurt the company when Apple switched media processor chip vendors in its iPod lines.
On January 5, 2007, Nvidia Corporation announced that it had acquired PortalPlayer, Inc. for about $357 million.
Products
PortalPlayer 5002
Dual ARM7TDMI cores with shared SRAM (3x 32KB banks). Errata in memory controller leads to halved data cache performance but fast SRAM. As the ARM7TDMI does not support cache coherency, individual ARM7TDMI cores do not have coherent views of DRAM. Custom logic is used to introduce coherency into the SRAM.
Used by the following devices:
iPod: Generations 1, 2 and 3
PortalPlayer 5003
System-on-a-chip containing two ARM7 CPU cores, each running at up to 90 MHz. Fixes 5002 cache bug greatly improving performance of DRAM.
Used by the following devices:
Rio Karma
PortalPlayer 5020
System-on-a-chip containing two ARM CPU cores, each running at 75 MHz. Expanded
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https://en.wikipedia.org/wiki/LTK
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LTK may refer to the
LTK Commune
Leukocyte receptor tyrosine kinase, in biochemistry, a member of the receptor tyrosine kinase family of cell surface receptors
Bassel Al-Assad International Airport, the airport of Latakia, Syria (IATA code).
Licence to Kill, 1989 James Bond film
LIKEtoKNOW.it, shopping app which became LTK in 2021
Little Kimble railway station, England; National Rail station code LTK
Legends of the Three Kingdoms, a Chinese popular card game based on the Three Kingdoms period of China and the semi-fictional novel Romance of the Three Kingdoms (ROTK).
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https://en.wikipedia.org/wiki/Francis%20T.%20Purcell
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Francis Thomas Purcell (August 11, 1918 – May 18, 2014) was a Republican politician who was county executive of Nassau County, New York (1978–87). He served as a trustee and also as mayor of the village of Malverne, was a member of the New York State Assembly, and supervisor of the town of Hempstead, New York, before becoming county executive in 1978. After resigning in 1987, Purcell became a political commentator for Cablevision's news channel News 12 Long Island. In 2004, a section of land formerly called Hempstead Plains was dedicated to Purcell in honor of his service and dedication to Nassau County.
Early life
Purcell was born in 1918 to Thomas (d. 1942) and Annette (d. 1972) Purcell on 11 August 1918 in Brooklyn, New York. A star athlete at Malverne High School, he was signed to play baseball with the Brooklyn Dodgers but never played for them because he joined the army in 1941 and was discharged in 1945 with the rank of captain.
Career
Purcell was elected mayor of Malverne in 1955. In June 1964, he challenged the party designee in the Republican Party primary for Nassau's 1st district's seat in the New York State Assembly and won the nomination. He was a member of the State Assembly in 1965. On June 18, he was appointed as supervisor of the town of Hempstead, to fill the vacancy created by the appointment of Ralph G. Caso as presiding supervisor. Purcell was elected to the position in November 1965, and then reelected twice.
He was elected to the post of county exe
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https://en.wikipedia.org/wiki/Soft%20handover
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Soft handover or soft handoff refers to a feature used by the CDMA and W-CDMA standards, where a cell phone is simultaneously connected to two or more cells (or cell sectors) during a call. If the sectors are from the same physical cell site (a sectorised site), it is referred to as softer handoff. This technique is a form of mobile-assisted handover, for IS-95/CDMA2000 CDMA cell phones continuously make power measurements of a list of neighboring cell sites, and determine whether or not to request or end soft handover with the cell sectors on the list.
Due to the properties of the CDMA signaling scheme, it is possible for a CDMA phone to simultaneously receive signals from two or more radio base stations that are transmitting the same bit stream (using different transmission codes) on the different physical channels in the same frequency bandwidth. If the signal power from two or more radio base stations is nearly the same, the phone receiver can combine the received signals in such a way that the bit stream is decoded much more reliably than if only one base station were transmitting to the subscriber station. If any one of these signals fades significantly, there will be a relatively high probability of having adequate signal strength from one of the other radio base stations.
On the uplink (phone-to-cell-site), all the cell site sectors that are actively supporting a call in soft handover send the bit stream that they receive back to the Radio Network Controller (RNC),
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https://en.wikipedia.org/wiki/C31%20Melbourne
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C31 Melbourne is a free-to-air community television channel in Melbourne, Victoria, Australia. Its name is derived from UHF 31, the frequency and channel number reserved for analogue broadcasts by metropolitan community television stations in Australia.
History
The station began broadcasting officially on 6 October 1994. The Australian Broadcasting Authority had granted Melbourne Community Television Consortium (MCTC) with a temporary open-narrowcast licence on 5 March 1993. The framework of community television in Australia can be traced back to 1992, when the Government asked the ABA to conduct a trial of community television using the vacant sixth television channel 31. On 30 July 2004, the Australian Broadcasting Authority granted the station a full-time community broadcasting licence.
C31 began broadcasting in digital during June 2010.
C31 is primarily funded through sponsorship, grants, sale of airtime and member donations. The station does not receive any regular Government funding. The annual revenue of C31 is approximately (AUD) $1.3 million per year. For comparison, the Nine Network, an Australian commercial station, has $907 million annual revenue. The station claims that "1.4 million Melburnians tune in each month" this figure is supplied by the ratings company OzTam. Individual programs can have ratings of up to 180,000 viewers.
The C31 website was completely remodelled in 2009, offering streaming of every program they broadcast (if the producer consents).
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https://en.wikipedia.org/wiki/Acoustic%20metric
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In acoustics and fluid dynamics, an acoustic metric (also known as a sonic metric) is a metric that describes the signal-carrying properties of a given particulate medium.
(Generally, in mathematical physics, a metric describes the arrangement of relative distances within a surface or volume, usually measured by signals passing through the region – essentially describing the intrinsic geometry of the region.)
A simple fluid example
For simplicity, we will assume that the underlying background geometry is Euclidean, and that this space is filled with an isotropic inviscid fluid at zero temperature (e.g. a superfluid). This fluid is described by a density field ρ and a velocity field . The speed of sound at any given point depends upon the compressibility which in turn depends upon the density at that point. It requires much work to compress anything more into an already compacted space. This can be specified by the "speed of sound field" c. Now, the combination of both isotropy and Galilean covariance tells us that the permissible velocities of the sound waves at a given point x, has to satisfy
This restriction can also arise if we imagine that sound is like "light" moving through a spacetime described by an effective metric tensor called the acoustic metric.
The acoustic metric is
"Light" moving with a velocity of (not the 4-velocity) has to satisfy
If
where α is some conformal factor which is yet to be determined (see Weyl rescaling), we get the desired velocity re
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https://en.wikipedia.org/wiki/Panel%20data
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In statistics and econometrics, panel data and longitudinal data are both multi-dimensional data involving measurements over time. Panel data is a subset of longitudinal data where observations are for the same subjects each time.
Time series and cross-sectional data can be thought of as special cases of panel data that are in one dimension only (one panel member or individual for the former, one time point for the latter). A literature search often involves time series, cross-sectional, or panel data. Cross-panel data (CPD) is an innovative yet underappreciated source of information in the mathematical and statistical sciences. CPD stands out from other research methods because it vividly illustrates how independent and dependent variables may shift between countries. This panel data collection allows researchers to examine the connection between variables across several cross-sections and time periods and analyze the results of policy actions in other nations.
A study that uses panel data is called a longitudinal study or panel study.
Example
In the multiple response permutation procedure (MRPP) example above, two datasets with a panel structure are shown and the objective is to test whether there's a significant difference between people in the sample data. Individual characteristics (income, age, sex) are collected for different persons and different years. In the first dataset, two persons (1, 2) are observed every year for three years (2016, 2017, 2018). In the seco
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https://en.wikipedia.org/wiki/List%20of%20Zimbabwe%20ODI%20cricketers
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This is a list of Zimbabwean One-day International cricketers displaying career statistics for all players that have represented Zimbabwe in at least one One Day International (ODI). An ODI is an international cricket match between two representative teams, each having ODI status, as determined by the International Cricket Council (ICC). An ODI differs from Test matches in that the number of overs per team is limited, and that each team has only one innings. The list is arranged in the order in which each player won his first ODI cap. Where more than one player won his first ODI cap in the same match, those players are listed alphabetically by surname.
Key
Players
Statistics are correct as of 4 July 2023.
Notes
See also
One Day International
Zimbabwean cricket team
List of Zimbabwe Test cricketers
List of Zimbabwe Twenty20 International cricketers
Notes
External links
Howstat
Cricinfo
References
Zimbabwe ODI
Zimbabwe
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https://en.wikipedia.org/wiki/Nikolay%20Koksharov
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Nikolai Ivanovich Koksharov () (23 November (5 December), 1818 – 21 December (2 January), 1893) was a Russian mineralogist, crystallographer, and major general in the Russian army. He was noted for his measurements of crystals using a goniometer.
Life
Nikolai Koksharov was born in Ust-Kamenogorsk (today's Kazakhstan). He was educated at the military school of mines in St. Petersburg. At the age of twenty-two he was selected to accompany Roderick Murchison and Édouard de Verneuil, and afterwards Dr. Keyserling, in their geological survey of the Russian Empire. Subsequently, he devoted his attention mainly to the study of mineralogy and mining, and was appointed director of the Institute of Mines. In 1865, he became director of the Imperial Mineralogical Society of St.Petersburg. He contributed numerous papers on euclase, zircon, epidote, orthite, monazite, and other mineralogical subjects to the St.Petersburg and Vienna academies of science, to Johann Christian Poggendorff's Annalen der Physik und Chemie, Leonhard and Browns Ja/irbuch, &c. He also issued as separate works Materialen zur Mineralogie Russlands and Vorlesungen uber Mineralogie.
References
Further reading
Russian mineralogists
Full members of the Saint Petersburg Academy of Sciences
Russian people of Kazakhstani descent
1818 births
1893 deaths
Burials at Nikolskoe Cemetery
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https://en.wikipedia.org/wiki/Intestinal%20neuronal%20dysplasia
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Intestinal neuronal dysplasia (IND) is an inherited disease of the intestine that affects one in 3000 children and adults. The intestine uses peristalsis to push its contents toward the anus; people with IND have a problem with the motor neurons that lead to the intestine, inhibiting this process and thus preventing digestion.
It can often be confused for Hirschsprung's disease, as both have similar symptoms.
Presentation
IND can be grouped into NID A and NID B, with the "A" form affecting the sympathetic innervation, and the "B" version affecting the parasympathetic innervation.
In 2002 Martucciello and colleagues published the first analysis of associated anomalies in IND population is an important clinical approach to investigate possible pathogenetic correlations. Two recessive syndromes were identified (3 families). The first was characterized by NID B, intestinal malrotation, and congenital short bowel, the second by NID B, short stature, mental retardation, and facial dysmorphism. In this study, gastrointestinal anomalies accounted for 67.4% of all associated disorders. These data suggest a strong correlation between IND and intestinal development.
Diagnosis
Treatment
Conservative treatment involves the long term use of laxatives and enemas, and has limited success. Dietary changes in order to control the disease are ineffective and high fiber diets often worsen the symptoms in children. As a last resort, surgical treatment (internal sphincter myectomy or colon res
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https://en.wikipedia.org/wiki/Verteporfin
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Verteporfin (trade name Visudyne), a benzoporphyrin derivative, is a medication used as a photosensitizer for photodynamic therapy to eliminate the abnormal blood vessels in the eye associated with conditions such as the wet form of macular degeneration. Verteporfin accumulates in these abnormal blood vessels and, when stimulated by nonthermal red light with a wavelength of 689 nm in the presence of oxygen, produces highly reactive short-lived singlet oxygen and other reactive oxygen radicals, resulting in local damage to the endothelium and blockage of the vessels.
Verteporfin is also used off-label for the treatment of central serous retinopathy.
Administration
Verteporfin is usually injected intravenously into the largest arm vein. It is injected at a dose of 6 mg/m2 and light-activated. It is usually given 15 minutes before laser treatment. This dose can be repeated 4 times per year.
Contraindications
Porphyria.
Side effects
Most common side effects are blurred vision, headache, and local effects at the injection site. Also, photosensitivity; it is strictly advised to avoid exposure to sunlight and unscreened lighting until 48 hours after verteporfin administration.
Dogs and rats have been treated with inactivated daily doses 32–70 times higher than the dose advised for humans. The 4 weeks of treatment resulted in mild extravascular hemolysis and hematopoiesis in the animals.
Interactions
Verteporfin is known to interact with the herbal remedy feverfew (Tanacetum
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https://en.wikipedia.org/wiki/Ehrenfest
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Ehrenfest is a surname. Notable people with the surname include:
Paul Ehrenfest (1880-1933), Austrian physicist and mathematician
Ehrenfest equations
Ehrenfest model
Ehrenfest paradox
Ehrenfest theorem
32796 Ehrenfest
Tatjana Ehrenfest-Afanassjewa (1876-1964), Ukrainian-Russian mathematician, wife of Paul
Tanja van Aardenne-Ehrenfest (1905–1984), Austrian Dutch mathematician, daughter of Paul
See also
Ehrenfeld (disambiguation)
Ehrenfels (disambiguation)
Ehrenbaum
Ehrenberg (disambiguation)
Ehrenburg (disambiguation)
Ehrenhaft
Ehrenpreis
Ehrenstein
Ehrenthal
German-language surnames
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https://en.wikipedia.org/wiki/Cisterna%20magna
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The cisterna magna (posterior cerebellomedullary cistern, or cerebellomedullary cistern) is the largest of the subarachnoid cisterns. It occupies the space created by the angle between the caudal/inferior surface of the cerebellum, and the dorsal/posterior surface of the medulla oblongata (it is created by the arachnoidea that bridges this angle). The fourth ventricle communicates with the cistern via the unpaired midline median aperture. It is continuous inferiorly with the subarachnoid space of the spinal canal.
The cisterna magna contains the two vertebral arteries, the origins of the two posterior inferior cerebellar arteries, the glossopharyngeal nerve (CN IX), vagus nerve (CN X), accessory nerve (CN XI), hypoglossal nerve (XII), and choroid plexus. The vertebral artery and posterior inferior cerebellar artery of either side pass traverse either lateral portion of the cistern.
Etymology
The Terminologia Anatomica classifies the terms cisterna magna and posterior cerebellomedullary cistern as synonyms. It does not recognise the term "cerebellomedullary cistern" (neither as a synonym or distinct structure) but acknowledges the lateral cerebellomedullary cistern as a distinct structure.
The 42th edition of Gray's Anatomy (2020) and 12th edition of Last's Anatomy (2011) recognise the cisterna magna and cerebellomedullary cistern as synonyms, and do not describe a separate lateral cerebellomedullary cistern.
According to the 8th edition of the Clinical Oriented Anatomy (
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https://en.wikipedia.org/wiki/ADM-160%20MALD
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The ADM-160 MALD (Miniature Air-Launched Decoy) is a decoy missile developed by the United States.
It uses gradient-index optics to create a radar cross section that simulates an airplane, in order to confuse missile defense systems.
Overview
DARPA MALD program
The Miniature Air-Launched Decoy (MALD) program was begun in 1995 by DARPA in an effort to develop a small, low-cost decoy missile for use in the Suppression of Enemy Air Defenses. Teledyne Ryan (acquired by Northrop Grumman in 1999) was granted a development contract for the ADM-160A in 1996, and the first test flight took place in 1999. The evaluation program was finished by 2001.
The US Air Force planned to acquire several thousand of ADM-160As, but in 2001 this was reduced to at most 150 for a System Development and Demonstration (SDD) program. In January 2002, the USAF cancelled the program because the drone didn't have enough range and endurance to meet the service's requirements or to perform other missions.
The ADM-160A carries a Signature Augmentation Subsystem (SAS) which is composed of various active radar enhancers which cover a range of frequencies. The SAS can therefore simulate any aircraft, from the B-52 Stratofortress to the F-117 Nighthawk.
The missile has folded wings to allow more compact carriage. On launch the wings unfold and a TJ-50 turbojet propels the missile on a pre-determined course which is composed of up to 100 different waypoints. An inertial navigation system with GPS support keep
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https://en.wikipedia.org/wiki/Sedna%20IV
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The S/Y Sedna IV is a three-masted schooner which has been used for scientific expeditions and the filming of documentaries.
Built by Abeking & Rasmussen in Germany in 1957 as a Sidefishing Trawler, refitted as a sailing vessel in 1992, she was equipped with a film studio in 2001 when a Canadian film crew acquired her. The ship was previously named Saint Kilda. Sedna IV is fitted out with a cutting room and an equipment room containing high-definition filmmaking apparatus. The crew can use the onboard high-precision scientific equipment to gather, compile and analyze data to fulfill the expedition's scientific research program. The schooner is also connected to the internet via satellite, enabling land-based researchers to become virtual mariners.
The schooner has a diesel reserve giving her a range of . She is also equipped with of sailcloth.
Ship's log
27.04.1957: launched at Abeking & Rasmussen, Lemwerder, Germany, NB 5169
07.06.1957: delivered as combined motorlogger (herring drifter and sidefishing trawler), 31.39 23.33 GRT 147.84 NRT, 4x 7.94 x 3.62 m, engine: Deutz SBV6 M545 Diesel 4s6c 600 hp, Bielefeld BV 106, callsign DLDQ, to Bremen-Vegesacker Fischerei-Gesellschaft, Vegesack, Germany
08.07.1964: sailed into Lerwick, sailed out the next day
05.05.1966: owners restyled to Bremen-Vegesacker Fischerei-Gesellschaft mbH, Bremen-Vegesack
08.1969: ownership moved to Norddeutsche Hochseefischerei Bremerhaven, fishing off West Africa, under leasing arrangement to
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https://en.wikipedia.org/wiki/Superstabilization
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Superstabilization is a concept of fault-tolerance in distributed computing. Superstabilizing distributed algorithms combine the features of self-stabilizing algorithms and dynamic algorithms. A superstabilizing algorithm – just like any other self-stabilizing algorithm – can be started in an arbitrary state, and it will eventually converge to a legitimate state. Additionally, a superstabilizing algorithm will recover rapidly from a single change in the network topology (adding or removing one edge or node in the network).
Any self-stabilizing algorithm recovers from a change in the network topology – the system configuration after a topology change can be treated just like any other arbitrary starting configuration. However, in a self-stabilizing algorithm, the convergence after a single change in the network topology may be as slow as the convergence from an arbitrary starting state. In the study of superstabilizing algorithms, special attention is paid to the time it takes to recover from a single change in the network topology.
Definitions
The stabilization time of a superstabilizing algorithm is defined exactly as in the case of self-stabilizing algorithm: how long it takes to converge to a legitimate state from an arbitrary configuration. Depending on the computational model, time is measured, e.g., in synchronous communication rounds or in asynchronous cycles.
The superstabilization time is the time to recover from a single topology change. It is assumed that the s
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https://en.wikipedia.org/wiki/Sponka.tv
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Sponka.tv is a Slovenian regional television station most notable for the Frequency Controversy it was involved in from 2003 to 2010. It broadcasts in the regions of Koper, Sežana and Nova Gorica.
Sponka.tv was born as a Cable TV channel, and has only been broadcasting on terrestrial TV since 2003.
Programmes
The station broadcasts mostly local news, local sports, and music, as well as advertisement and pornographic films at late night. It claims to be the voice of the culture and the people of the Slovenian Littoral.
Programme Controversy
The programming is not without controversy. For example, the pornographic films are broadcast too early, starting at 22:00, even though Slovenian law prohibits their broadcast at that kind of time. In addition, the music broadcast by the station is mostly Balkan (Serbian turbofolk) which has nothing to do with the Slovenian Littoral.
Frequency Controversy
The station is controversial, because it transmits, from the local repeater of Tinjan, near the town of Koper, on the Slovenian Littoral, on the channel UHF 52. However, in the same area, on the same channel, transmits, from the repeater of Conconello in Trieste (but also receivable on the same frequency from the repeaters of Monte Madonna (Teolo) in Padova, Prati della Chiesa (Pedrosa) Udine, and Monte San Michele (Sagrado) in Gorizia), the Italian private channel Italia Uno, which is the most watched channel by the youths of both Italy, and the Slovenian Littoral.
Beginning
The cont
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https://en.wikipedia.org/wiki/Erlotinib
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Erlotinib, sold under the brand name Tarceva among others, is a medication used to treat non-small cell lung cancer (NSCLC) and pancreatic cancer. Specifically it is used for NSCLC with mutations in the epidermal growth factor receptor (EGFR) — either an exon 19 deletion (del19) or exon 21 (L858R) substitution mutation — which has spread to other parts of the body. It is taken by mouth.
Common side effects include rash, diarrhea, muscle pain, joint pain, and cough. Serious side effects may include lung problems, kidney problems, liver failure, gastrointestinal perforation, stroke, and corneal ulceration. Use in pregnancy may harm the baby. It is a receptor tyrosine kinase inhibitor, which acts on the epidermal growth factor receptor (EGFR).
Erlotinib was approved for medical use in the United States in 2004. It is on the World Health Organization's List of Essential Medicines.
Medical uses
Lung cancer
Erlotinib in unresectable non-small cell lung cancer when added to chemotherapy improves overall survival by 19%, and improved progression-free survival (PFS) by 29%, when compared to chemotherapy alone. The U.S. Food and Drug Administration (FDA) approved erlotinib for the treatment of locally advanced or metastatic non-small cell lung cancer that has failed at least one prior chemotherapy regimen.
In lung cancer, erlotinib has been shown to be effective in patients with or without EGFR mutations, but appears to be more effective in patients with EGFR mutations. Overall su
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https://en.wikipedia.org/wiki/Biocatalysis
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Biocatalysis refers to the use of living (biological) systems or their parts to speed up (catalyze) chemical reactions. In biocatalytic processes, natural catalysts, such as enzymes, perform chemical transformations on organic compounds. Both enzymes that have been more or less isolated and enzymes still residing inside living cells are employed for this task. Modern biotechnology, specifically directed evolution, has made the production of modified or non-natural enzymes possible. This has enabled the development of enzymes that can catalyze novel small molecule transformations that may be difficult or impossible using classical synthetic organic chemistry. Utilizing natural or modified enzymes to perform organic synthesis is termed chemoenzymatic synthesis; the reactions performed by the enzyme are classified as chemoenzymatic reactions.
History
Biocatalysis underpins some of the oldest chemical transformations known to humans, for brewing predates recorded history. The oldest records of brewing are about 6000 years old and refer to the Sumerians.
The employment of enzymes and whole cells have been important for many industries for centuries. The most obvious uses have been in the food and drink businesses where the production of wine, beer, cheese etc. is dependent on the effects of the microorganisms.
More than one hundred years ago, biocatalysis was employed to do chemical transformations on non-natural man-made organic compounds, with the last 30 years seeing a subs
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https://en.wikipedia.org/wiki/Sugilite
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Sugilite ( ) is a relatively rare pink to purple cyclosilicate mineral with the complex chemical formula KNa2(Fe, Mn, Al)2Li3Si12O30. Sugilite crystallizes in the hexagonal system with prismatic crystals. The crystals are rarely found and the form is usually massive. It has a Mohs hardness of 5.5–6.5 and a specific gravity of 2.75–2.80. It is mostly translucent.
Sugilite was first described in 1944 by the Japanese petrologist Ken-ichi Sugi (1901–1948) for an occurrence on Iwagi Islet, Japan, where it is found in an aegirine syenite intrusive stock. It is found in a similar environment at Mont Saint-Hilaire, Quebec, Canada. In the Wessels mine in Northern Cape Province of South Africa, sugilite is mined from a strata-bound manganese deposit. It is also reported from Liguria and Tuscany, Italy; New South Wales, Australia and Madhya Pradesh, India.
Sugilite is commonly pronounced with a soft "g", as in "ginger". However, as with most minerals, its pronunciation is intended to be the same as the person it is named after; in this case, the Japanese name Sugi has a hard "g", as in "geese".
The mineral is also referred to as lavulite, luvulite, and royal azel by gem and mineral collectors.
See also
List of minerals
List of minerals named after people
References
Potassium minerals
Sodium minerals
Iron minerals
Manganese minerals
Aluminium minerals
Lithium minerals
Cyclosilicates
Gemstones
Hexagonal minerals
Minerals in space group 192
Minerals described in 1944
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https://en.wikipedia.org/wiki/British%20Rail%20Class%2082
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The British Rail Class 82 (AL2 under the pre-TOPS classification scheme) electric locomotives were designed by the British manufacturing interest Metropolitan-Vickers and produced by Beyer, Peacock and Company on behalf of British Rail (BR).
The locomotive was developed as a part of the programme of works to electrify the West Coast Main Line during the late 1950s and early 1960s. BR deliberately opted to procure multiple small batches of locomotives from a range of manufacturers. Having selected a proposal by the Metropolitan-Vickers division of the British manufacturing interest Associated Electrical Industries (AEI), the Class 82 would be produced. A total of ten locomotives were built by Beyer, Peacock and Company between 1960 and 1962.
The Class 82 proved to be a relatively reliable workhorse of the region, particularly following a refurbishment during the 1970s that saw the replacement of their rectifiers. The fleet served in their original capacity for roughly twenty years, being mostly withdrawn during the early 1980s following the arrival of newer types such as the British Rail Class 87. Following the final retirement of the Class 82 in 1987, a single example was preserved.
Background
During the late 1950s, British Rail (BR) embarked upon the electrification of the West Coast Main Line, a strategy which necessitated the procurement of a large number of electric locomotives to utilise the newly installed infrastructure. It was decided that, instead of a bulk order
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https://en.wikipedia.org/wiki/Tak%20Wah%20Mak
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Tak Wah Mak, (; born October 4, 1946, in China) is a Canadian medical researcher, geneticist, oncologist, and biochemist. He first became widely known for his discovery of the T-cell receptor in 1983 and pioneering work in the genetics of immunology. In 1995, Mak published a landmark paper on the discovery of the function of the immune checkpoint protein CTLA-4, thus opening the path for immunotherapy/checkpoint inhibitors as a means of cancer treatment. Mak is also the founder of Agios Pharmaceuticals, whose lead compound, IDHIFA®, was approved by the FDA for acute myeloid leukemia in August 2017, becoming the first drug specifically targeting cancer metabolism to be used for cancer treatment. He has worked in a variety of areas including biochemistry, immunology, and cancer genetics.
Early life
Born in southern China in 1946 to parents who were silk merchants, and raised in Hong Kong, parents encouraged him to become a doctor, his interests lay elsewhere—in math, biology, and chemistry. Mak and his family moved to the United States of America during the mid-1960s and with the choice of going to the University of California or Wisconsin, he was persuaded by his mother to attend Wisconsin to avoid the antiwar activities at California. His interest in life and chemistry led him to eventually studying biochemistry and biophysics at the University of Wisconsin.
University life
At the University of Wisconsin, Mak met virologist Roland Rueckert. Mak initially went to his lab t
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https://en.wikipedia.org/wiki/Descloizite
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Descloizite is a rare mineral species consisting of basic lead and zinc vanadate, , crystallizing in the orthorhombic crystal system and isomorphous with olivenite. Appreciable gallium and germanium may also be incorporated into the crystal structure.
The color is deep cherry-red to brown or black, and the crystals are transparent or translucent with a greasy lustre; the streak is orange-yellow to brown; specific gravity 5.9 to 6.2; hardness 31/2. A variety known as cuprodescloizite is dull green in color; it contains a considerable amount of copper replacing zinc and some arsenic replacing vanadium. There is also an arsenate analogue called arsendescloizite.
Discovery and occurrence
It was discovered in the Sierra de Córdoba deposit in Córdoba, Argentina, in 1854 and named in honor of the French mineralogist Alfred Des Cloizeaux (1817–1897). It occurs as small prismatic or pyramidal crystals, usually forming drusy crusts and stalactitic aggregates; also as fibrous encrusting masses with a mammillary surface.
Descloizite occurs in oxidised portions of veins of lead ores in association with pyromorphite, vanadinite, wulfenite, mottramite, mimetite and cerussite.
The Otavi ("O-tarvi") Mountainland of northern Namibia was once considered home to the greatest vanadium deposits in the world, including those at Berg Aukas ("OW-cuss"), Abenab ("UB-en-ub"), Baltika ("BUL-tika") and Uitsab ("ATE-sub"). Descloizite and mottramite were the main ore minerals in each of these deposi
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https://en.wikipedia.org/wiki/Hormonal%20sentience
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Hormonal sentience, first described by Robert A. Freitas Jr., describes the information processing rate in plants, which are mostly based on hormones instead of neurons like in all major animals (except sponges). Plants can to some degree communicate with each other and there are even examples of one-way-communication with animals.
Acacia trees produce tannin to defend themselves when they are grazed upon by animals. The airborne scent of the tannin is picked up by other acacia trees, which then start to produce tannin themselves as a protection from the nearby animals.
When attacked by caterpillars, some plants can release chemical signals to attract parasitic wasps that attack the caterpillars.
A similar phenomenon can be found not only between plants and animals, but also between fungi and animals. There exists some sort of communication between a fungus garden and workers of the leaf-cutting ant Atta sexdens rubropilosa. If the garden is fed with plants that are poisonous for the fungus, it signals this to the ants, which then will avoid fertilizing the fungus garden with any more of the poisonous plant.
The Venus flytrap, during a 1- to 20-second sensitivity interval, counts two stimuli before snapping shut on its insect prey, a processing peak of 1 bit/s. Mass is 10–100 grams, so the flytrap's SQ is about +1. Plants generally take hours to respond to stimuli though, so vegetative SQs (Sentience Quotient) tend to cluster around -2.
See also
Biosemiotics
Phytosemioti
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https://en.wikipedia.org/wiki/Struvite
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Struvite (magnesium ammonium phosphate) is a phosphate mineral with formula: NH4MgPO4·6H2O. Struvite crystallizes in the orthorhombic system as white to yellowish or brownish-white pyramidal crystals or in platy mica-like forms. It is a soft mineral with Mohs hardness of 1.5 to 2 and has a low specific gravity of 1.7. It is sparingly soluble in neutral and alkaline conditions, but readily soluble in acid.
Struvite urinary stones and crystals form readily in the urine of animals and humans that are infected with ammonia-producing organisms. They are potentiated by alkaline urine and high magnesium excretion (high magnesium/plant-based diets). They also are potentiated by a specific urinary protein in domestic cats.
Name
Although struvite was briefly mentioned in Hooke's Micrographia, it was first described in detail in 1845 by the German chemist (1811–1883), who found crystals of struvite in what he surmised had once been a medieval midden in Hamburg, Germany; he named the new mineral after the geographer and geologist (1772–1851) of Hamburg.
Occurrence
Struvite readily forms in alkaline conditions where its constituent ions are present. In nature, it forms primarily in areas associated with organic matter decomposition, including guano deposits, basaltic caves, and marshlands. Similar conditions are found when human bladders are infected by urease-producing bacteria, when wastewater is treated, etc.
Struvite is occasionally found in canned seafood, where its appearance
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https://en.wikipedia.org/wiki/Herkimer%20diamond
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Herkimer diamonds are double-terminated quartz crystals discovered within exposed outcrops of dolomite in and around Herkimer County, New York and the Mohawk River Valley in the US. They are not diamonds; the "diamond" in their name is due to both their clarity and natural faceting. Crystals possess double termination points and 18 total faces (six on each point, six around the center). Because the first discovery sites were in the village of Middleville and in the city of Little Falls, respectively, the crystal is also known as a Middleville diamond or a Little Falls diamond.
Herkimer diamonds became widely recognized after workmen discovered them in large quantities while cutting into the Mohawk River Valley dolomite in the late 18th century. Geologists discovered exposed dolomite in Herkimer County outcroppings and began mining there, leading to the "Herkimer diamond" moniker. Double-point quartz crystals may be found in sites around the world, but only those mined in Herkimer County can be given this name.
Process of formation
The geologic history of these crystals began about 500 million years ago in a shallow sea which was receiving sediments from the ancient Adirondack Mountains to the north. The calcium and magnesium carbonate sediments accumulated and lithified to form the dolomite bedrock currently known as the Little Falls Formation and formerly as the Little Falls Dolostone. While buried, cavities were formed by acidic waters forming the vugs in which the quart
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https://en.wikipedia.org/wiki/Afwillite
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Afwillite is a calcium hydroxide nesosilicate mineral with formula Ca3(SiO3OH)2·2H2O. It occurs as glassy, colorless to white prismatic monoclinic crystals. Its Mohs scale hardness is between 3 and 4. It occurs as an alteration mineral in contact metamorphism of limestone. It occurs in association with apophyllite, natrolite, thaumasite, merwinite, spurrite, gehlenite, ettringite,
portlandite, hillebrandite, foshagite, brucite and calcite.
It was first described in 1925 for an occurrence in the Dutoitspan Mine, Kimberley, South Africa and was named for Alpheus Fuller Williams (1874–1953), a past official of the De Beers diamond company.
Afwillite is typically found in veins of spurrite and it belongs to the nesosilicate sub-class. It is monoclinic, its space group is P2 and its point group is 2.
Formation of afwillite
It is suggested that afwillite forms in fractured veins of the mineral spurrite. Jennite, afwillite, oyelite and calcite are all minerals that form in layers within spurrite veins. It appears that afwillite, as well as calcite, forms from precipitated fluids. Jennite is actually an alteration of afwillite, but both formed from calcium silicates through hydration. Laboratory studies determined that afwillite forms at a temperature below , usually around 100 °C. Afwillite and spurrite are formed through contact metamorphism of limestone. Contact metamorphism is caused by the interaction of rock with heat and/or fluids from a nearby crystallizing silicate magma.
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https://en.wikipedia.org/wiki/AVM
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AVM may refer to:
Medicine and biology
Acute viral meningitis, inflammation of the protective membranes covering the brain and spinal cord, caused by a viral infection
Arteriovenous malformation, a congenital disorder of the veins and arteries that make up the vascular system
Cerebral arteriovenous malformation, an abnormal connection of the veins and arteries in the brain
Avian vacuolar myelinopathy, a fatal neurological disease
Other
ActionScript Virtual Machine, a component of Adobe Flash Player
Adaptive Vehicle Make, a United States military project to design and manufacture defense systems and vehicles
Adarsha Vidya Mandir, a school in Lalitpur, Nepal
Air Vice-Marshal, a rank in the United Kingdom and many Commonwealth air forces
Associação Visão de Macau or Vision Macau, a political party in Macao
Astronomy Visualization Metadata, a standard for tagging digital astronomical images with astronomical information
Attribute value matrix, a compact notation in linguistics for listing attribute-value pairs describing a lexical entity
Automated Valuation Model, a mathematical model for analysis of residential property
Automatic vehicle monitoring, one of the applications of vehicle tracking systems
AVM GmbH, a German manufacturer of broadband modems and consumer networking devices
AVM Productions, a film production house in Tamil Nadu, India
A. V. Meiyappan, Indian filmmaker, founder of AVM Productions
AVM Runestone, an archaeological forgery found in 2001 near Kensington, M
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https://en.wikipedia.org/wiki/ISUP
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ISUP may refer to:
Paris Institute of Statistics, a school for statistics in France
ISDN User Part or ISUP, a feature of Public Switched Telephone Networks
Inflatable Stand Up Paddle Board or iSUP, a water craft for the sport of Stand Up Paddling that is inflated rather than having a solid construction.
fr:ISUP
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https://en.wikipedia.org/wiki/Daitch%E2%80%93Mokotoff%20Soundex
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Daitch–Mokotoff Soundex (D–M Soundex) is a phonetic algorithm invented in 1985 by Jewish genealogists Gary Mokotoff and Randy Daitch. It is a refinement of the Russell and American Soundex algorithms designed to allow greater accuracy in matching of Slavic and Yiddish surnames with similar pronunciation but differences in spelling.
Daitch–Mokotoff Soundex is sometimes referred to as "Jewish Soundex" and "Eastern European Soundex", although the authors discourage use of these nicknames for the algorithm because the algorithm itself is independent of the fact that the motivation for creating the new system was the poor result of predecessor systems when dealing with Slavic and Yiddish surnames.
Improvements
Improvements over the older Soundex algorithms include:
Coded names are six digits long, resulting in greater search precision (traditional Soundex uses four characters)
The initial character of the name is coded.
Several rules in the algorithm encode multiple character n-grams as single digits (American and Russell Soundex do not handle multi-character n-grams)
Multiple possible encodings can be returned for a single name (traditional Soundex returns only one encoding, even if the spelling of a name could potentially have multiple pronunciations)
Examples
Some examples:
Beider–Morse Phonetic Name Matching Algorithm
To address the large number of false positive results generated by the D–M Soundex, Stephen P. Morse and Alexander Beider created the Beider–Morse Phon
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https://en.wikipedia.org/wiki/New%20York%20State%20Identification%20and%20Intelligence%20System
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The New York State Identification and Intelligence System Phonetic Code, commonly known as NYSIIS, is a phonetic algorithm devised in 1970 as part of the New York State Identification and Intelligence System (now a part of the New York State Division of Criminal Justice Services). It features an accuracy increase of 2.7% over the traditional Soundex algorithm.
Procedure
The algorithm, as described in Name Search Techniques, is:
If the first letters of the name are
'MAC' then change these letters to 'MCC'
'KN' then change these letters to 'NN'
'K' then change this letter to 'C'
'PH' then change these letters to 'FF'
'PF' then change these letters to 'FF'
'SCH' then change these letters to 'SSS'
If the last letters of the name are
'EE' then change these letters to 'Y␢'
'IE' then change these letters to 'Y␢'
'DT' or 'RT' or 'RD' or 'NT' or 'ND' then change these letters to 'D␢'
The first character of the NYSIIS code is the first character of the name.
In the following rules, a scan is performed on the characters of the name. This is described in terms of a program loop. A pointer is used to point to the current position under consideration in the name. Step 4 is to set this pointer to point to the second character of the name.
Considering the position of the pointer, only one of the following statements can be executed.
If blank then go to rule 7.
If the current position is a vowel (AEIOU) then if equal to 'EV' then change to 'AF' otherwise change current position to 'A'
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https://en.wikipedia.org/wiki/Retarded%20time
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In electromagnetism, electromagnetic waves in vacuum travel at the speed of light c, according to Maxwell's Equations. The retarded time is the time when the field began to propagate from the point where it was emitted to an observer. The term "retarded" is used in this context (and the literature) in the sense of propagation delays.
Retarded and advanced times
The calculation of the retarded time tr or t′ is nothing more than a simple "speed-distance-time" calculation for EM fields.
If the EM field is radiated at position vector r′ (within the source charge distribution), and an observer at position r measures the EM field at time t, the time delay for the field to travel from the charge distribution to the observer is |r − r′|/c, so subtracting this delay from the observer's time t gives the time when the field actually began to propagate - the retarded time, t′.
The retarded time is:
which can be rearranged to
showing how the positions and times correspond to source and observer.
Another related concept is the advanced time ta, which takes the same mathematical form as above, but with a “+” instead of a “−”:
and is so-called since this is the time the field will advance from the present time t. Corresponding to retarded and advanced times are retarded and advanced potentials.
Retarded position
The retarded position can be obtained from the current position of a particle by subtracting the distance it has travelled in the lapse from the retarded time to the curre
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https://en.wikipedia.org/wiki/Subculture%20%28biology%29
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In biology, a subculture is either a new cell culture or a microbiological culture made by transferring some or all cells from a previous culture to fresh growth medium. This action is called subculturing or passaging the cells. Subculturing is used to prolong the lifespan and/or increase the number of cells or microorganisms in the culture.
Role
Cell lines and microorganisms cannot be held in culture indefinitely due to the gradual rise in metabolites which may be toxic, the depletion of nutrients present in the culture medium, and an increase in cell count or population size due to growth. Once nutrients are depleted and levels of toxic byproducts increase, microorganisms in culture will enter the stationary phase, where proliferation is greatly reduced or ceased (the cell density value plateaus). When microorganisms from this culture are transferred into fresh media, nutrients trigger the growth of the microorganisms which will go through lag phase, a period of slow growth and adaptation to the new environment, followed by log phase, a period where the cells grow exponentially.
Subculture is therefore used to produce a new culture with a lower density of cells than the originating culture, fresh nutrients and no toxic metabolites allowing continued growth of the cells without risk of cell death. Subculture is important for both proliferating (e.g. a microorganism like E. coli) and non-proliferating (e.g. terminally differentiated white blood cells) cells. Subculturing ca
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https://en.wikipedia.org/wiki/Kell%20factor
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The Kell factor, named after RCA engineer Raymond D. Kell, is a parameter used to limit the bandwidth of a sampled image signal to avoid the appearance of beat frequency patterns when displaying the image in a discrete display device, usually taken to be 0.7. The number was first measured in 1934 by Raymond D. Kell and his associates as 0.64 but has suffered several revisions given that it is based on image perception, hence subjective, and is not independent of the type of display. It was later revised to 0.85 but can go higher than 0.9, when fixed pixel scanning (e.g., CCD or CMOS) and fixed pixel displays (e.g., LCD or plasma) are used, or as low as 0.7 for electron gun scanning.
From a different perspective, the Kell factor defines the effective resolution of a discrete display device since the full resolution cannot be used without viewing experience degradation. The actual sampled resolution will depend on the spot size and intensity distribution. For electron gun scanning systems, the spot usually has a Gaussian intensity distribution. For CCDs, the distribution is somewhat rectangular, and is also affected by the sampling grid and inter-pixel spacing.
Kell factor is sometimes incorrectly stated to exist to account for the effects of interlacing. Interlacing itself does not affect Kell factor, but because interlaced video must be low-pass filtered (i.e., blurred) in the vertical dimension to avoid spatio-temporal aliasing (i.e., flickering effects), the Kell factor o
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https://en.wikipedia.org/wiki/American%20Nutrition%20Association
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The American Nutrition Association (ANA) is a 501(c)(3) charitable non-profit organization established to encourage the scientific investigation of nutrition and metabolism. The ANA publishes the Journal of the American Nutrition Association and hosts scientific conferences in the US and in Europe.
Previously known as the American College of Nutrition, in 2019 together with the Board for Certification of Nutrition Specialists, the Center for Nutrition Advocacy, and the American Nutrition Association Foundation, affiliated together as the American Nutrition Association. The four organizations remain legally independent entities but share a single website together.
History
The American College of Nutrition was founded in 1959 with the stated purpose of enhancing nutrition and metabolism knowledge among physicians and professionals from all disciplines with a common interest in nutrition, and to promote the application of such knowledge to the maintenance of health and treatment of disease.
Merge proposal
In October 2010, the American College of Nutrition and American Society for Nutrition proposed to merge.
Structure
The ANA is governed by a member-elected Board of Directors and the current CEO of ANA is Michael Stroka. The organization also has several advisory components which include a Scientific Advisory Board, Strategic Advisory Board, Ketogenic Nutrition Training Program Development Team, and a Nutritional Genomics Advisory Panel.
European Chapter
The European chap
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https://en.wikipedia.org/wiki/Vietoris%E2%80%93Begle%20mapping%20theorem
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The Vietoris–Begle mapping theorem is a result in the mathematical field of algebraic topology. It is named for Leopold Vietoris and Edward G. Begle. The statement of the theorem, below, is as formulated by Stephen Smale.
Theorem
Let and be compact metric spaces, and let be surjective and continuous. Suppose that the fibers of are acyclic, so that
for all and all ,
with denoting the th reduced Vietoris homology group. Then, the induced homomorphism
is an isomorphism for and a surjection for .
Note that as stated the theorem doesn't hold for homology theories like singular homology. For example, Vietoris homology groups of the closed topologist's sine curve and of a segment are isomorphic (since the first projects onto the second with acyclic fibers). But the singular homology differs, since the segment is path connected and the topologist's sine curve is not.
References
"Leopold Vietoris (1891–2002)", Notices of the American Mathematical Society, vol. 49, no. 10 (November 2002) by Heinrich Reitberger
Theorems in algebraic topology
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https://en.wikipedia.org/wiki/Ure2p
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Ure2p is a yeast protein that represses transcription of genes involved in nitrogen catabolism. It specifically regulates the utilization of poor nitrogen sources in the presence of preferred nutrients such as ammonia or glutamine. Ure2p is one of the few yeast proteins that are known to be prions. At low frequency the protein adopts an alternative conformation that is auto-catalytic and self-propagating. Yeast cells that carry the protein in the prion conformation are designated as [URE3]. Autocatalytic conversion of Ure2p into the inactive prion form of the protein results in a loss of repression of nitrogen catabolic genes.
References
Prions
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https://en.wikipedia.org/wiki/Coherence%20%28statistics%29
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In probability theory and statistics, coherence can have several different meanings. Coherence in statistics is an indication of the quality of the information, either within a single data set, or between similar but not identical data sets. Fully coherent data are logically consistent and can be reliably combined for analysis.
In probability
When dealing with personal probability assessments, or supposed probabilities derived in nonstandard ways, it is a property of self-consistency across a whole set of such assessments.
In gambling strategy
One way of expressing such self-consistency is in terms of responses to various betting propositions, as described in relation to coherence (philosophical gambling strategy).
In Bayesian decision theory
The coherency principle in Bayesian decision theory is the assumption that subjective probabilities follow the ordinary rules/axioms of probability calculations (where the validity of these rules corresponds to the self-consistency just referred to) and thus that consistent decisions can be obtained from these probabilities.
In time series analysis
In time series analysis, and particularly in spectral analysis, it is used to describe the strength of association between two series where the possible dependence between the two series is not limited to simultaneous values but may include leading, lagged and smoothed relationships.
The concepts here are sometimes known as coherency and are essentially those set out for coherence as fo
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https://en.wikipedia.org/wiki/Anthodite
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Anthodites (Greek ἄνθος ánthos, "flower", -ode, adjectival combining form, -ite adjectival suffix) are speleothems (cave formations) composed of long needle-like crystals situated in clusters which radiate outward from a common base. The "needles" may be quill-like or feathery. Most anthodites are made of the mineral aragonite (a variety of calcium carbonate, CaCO3), although some are composed of gypsum (CaSO4·2H2O).
The term anthodite is first cited in the scientific literature in 1965 by Japanese researcher N. Kashima, who described "flower-like dripstone" composed of "an alternation of calcite and aragonite".
Structure, composition and appearance
The individual crystals of anthodites develop in a form described as "acicular" (needle-like) and often branch out as they grow. They usually grow downward from a cave's ceiling. Aragonite crystals are contrasted with those made of calcite (another variety of calcium carbonate) in that the latter tend to be stubby or dog-tooth-like ("rhombohedral", rather than acicular). Anthodites often have a solid core of aragonite and may have huntite or hydromagnesite deposited near the ends of the branches.
Anthodite crystals vary in size from less than a millimeter to about a meter, but are commonly between 1 and 20 millimeters in length.
Occurrence
Anthodites may occur sporadically throughout some limestone caves, but may be spectacularly abundant in others, with clean white crystals growing all over the calcite or other rock surface
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