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https://en.wikipedia.org/wiki/Pseudo-Euclidean%20space | In mathematics and theoretical physics, a pseudo-Euclidean space is a finite-dimensional real -space together with a non-degenerate quadratic form . Such a quadratic form can, given a suitable choice of basis , be applied to a vector , giving
which is called the scalar square of the vector .
For Euclidean spaces, , implying that the quadratic form is positive-definite. When , is an isotropic quadratic form, otherwise it is anisotropic. Note that if , then , so that is a null vector. In a pseudo-Euclidean space with , unlike in a Euclidean space, there exist vectors with negative scalar square.
As with the term Euclidean space, the term pseudo-Euclidean space may be used to refer to an affine space or a vector space depending on the author, with the latter alternatively being referred to as a pseudo-Euclidean vector space (see point–vector distinction).
Geometry
The geometry of a pseudo-Euclidean space is consistent despite some properties of Euclidean space not applying, most notably that it is not a metric space as explained below. The affine structure is unchanged, and thus also the concepts line, plane and, generally, of an affine subspace (flat), as well as line segments.
Positive, zero, and negative scalar squares
A null vector is a vector for which the quadratic form is zero. Unlike in a Euclidean space, such a vector can be non-zero, in which case it is self-orthogonal.
If the quadratic form is indefinite, a pseudo-Euclidean space has a linear cone of null vectors given by . When the pseudo-Euclidean space provides a model for spacetime (see below), the null cone is called the light cone of the origin.
The null cone separates two open sets, respectively for which and . If , then the set of vectors for which is connected. If , then it consists of two disjoint parts, one with and another with . Similarly, if , then the set of vectors for which is connected. If , then it consists of two disjoint parts, one with and another with .
Interval
The qua |
https://en.wikipedia.org/wiki/Indium%28III%29%20selenide | Indium(III) selenide is a compound of indium and selenium. It has potential for use in photovoltaic devices and has been the subject of extensive research. The two most common phases, α and β, have a layered structure, while γ has a "defect wurtzite structure." In all, five polymorphs are known: α, β, γ, δ, κ. The α-β phase transition is accompanied by a change in electrical conductivity. The band gap of γ-In2Se3 is approximately 1.9 eV.
Preparation
The method of production influences the polymorph generated. For example, thin films of pure γ-In2Se3 have been produced from trimethylindium (InMe3) and hydrogen selenide via MOCVD techniques.
A conventional route entails heating the elements in a seal-tube:
See also
Gallium(III) selenide
Indium chalcogenides
Nanoparticle
General references
WebElements
Footnotes
External links
Indium Selenide Nanoparticles Used In Solar Energy Conversion.
Indium compounds
Selenides
Solar cells
Semiconductor materials |
https://en.wikipedia.org/wiki/Subtract%20a%20square | Subtract-a-square (also referred to as take-a-square) is a two-player mathematical subtraction game. It is played by two people with a pile of coins (or other tokens) between them. The players take turns removing coins from the pile, always removing a non-zero square number of coins. The game is usually played as a normal play game, which means that the player who removes the last coin wins. It is an impartial game, meaning that the set of moves available from any position does not depend on whose turn it is. Solomon W. Golomb credits the invention of this game to Richard A. Epstein.
Example
A normal play game starting with 13 coins is a win for the first player provided they start with a subtraction of 1:
player 1: 13 - 1*1 = 12
Player 2 now has three choices: subtract 1, 4 or 9. In each of these cases, player 1 can ensure that within a few moves the number 2 gets passed on to player 2:
player 2: 12 - 1*1 = 11 player 2: 12 - 2*2 = 8 player 2: 12 - 3*3 = 3
player 1: 11 - 3*3 = 2 player 1: 8 - 1*1 = 7 player 1: 3 - 1*1 = 2
player 2: 7 - 1*1 = 6 or: 7 - 2*2 = 3
player 1: 6 - 2*2 = 2 3 - 1*1 = 2
Now player 2 has to subtract 1, and player 1 subsequently does the same:
player 2: 2 - 1*1 = 1
player 1: 1 - 1*1 = 0
player 2 loses
Mathematical theory
In the above example, the number '13' represents a winning or 'hot' position, whilst the number '2' represents a losing or 'cold' position. Given an integer list with each integer labeled 'hot' or 'cold', the strategy of the game is simple: try to pass on a 'cold' number to your opponent. This is always possible provided you are being presented a 'hot' number. Which numbers are 'hot' and which numbers are 'cold' can be determined recursively:
the number 0 is 'cold', whilst 1 is 'hot'
if all numbers 1 .. N have been classified as either 'hot' or 'cold', then
the number N+1 is 'cold' i |
https://en.wikipedia.org/wiki/Prefoldin | Prefoldin (GimC) is a superfamily of proteins used in protein folding complexes. It is classified as a heterohexameric molecular chaperone in both archaea and eukarya, including humans. A prefoldin molecule works as a transfer protein in conjunction with a molecule of chaperonin to form a chaperone complex and correctly fold other nascent proteins. One of prefoldin's main uses in eukarya is the formation of molecules of actin for use in the eukaryotic cytoskeleton.
Purpose and uses
Prefoldin is one family of chaperone proteins found in the domains of eukarya and archaea. Prefoldin acts in combination with other molecules to promote protein folding in cells where there are many other competing pathways for folding. Chaperone proteins perform non-covalent assembly of other polypeptide-containing structures in vivo. They are implicated in the folding of most other proteins.
In archaea, prefoldins are believed to function in combination with group II chaperonins in de novo protein folding. In eukarya however, prefoldins have acquired a more specific function: they are used to establish correct tubular assembly for many tubular proteins, such as actin. Actin accounts for 5-10% of all protein found in eukaryotic cells, which therefore means that prefoldin is quite prevalent in the cells. Actin is made of two strings of beads wound round each other and is one of the three main parts of the cytoskeleton of eukaryotic cells. Prefoldin bonds specifically to cytosolic chaperonin protein. This complex of prefoldin and chaperonin then forms molecules of actin in the cytosol. The prefoldin acts as a transporter molecule that transports bound, unfolded target proteins to the chaperonin (C-CPN) molecule.
For example, the prefoldin that is used in the formation of actin also transfers α or β tubulin to a cytosolic chaperonin. The prefoldin, however, does not form a ternary complex with tubulin and chaperonin. Once the tubulins are in contact with the chaperonin, the prefoldin au |
https://en.wikipedia.org/wiki/Lethal%20allele | Lethal alleles (also referred to as lethal or lethals) are alleles that cause the death of the organism that carries them. They are usually a result of mutations in genes that are essential for growth or development. Lethal alleles may be recessive, dominant, or conditional depending on the gene or genes involved.
Lethal alleles can be embryonically lethal, in which the fetus will never survive to term, or may be lethal perinatally or postnatally after an extended period of apparently normal development. Embryonically lethal alleles are a cause of non-Mendelian patterns of inheritance, such as the observation of traits in a 2:1 ratio.
History
Lethal alleles were first discovered by Lucien Cuénot in 1905 while studying the inheritance of coat colour in mice. The agouti gene in mice is largely responsible for determining coat colour. The wild-type allele produces a blend of yellow and black pigmentation in each hair of the mouse. This yellow and black blend may be referred to as 'agouti' in colour. One of the mutant alleles of the agouti gene results in mice with a much lighter, yellowish colour. When these yellow mice were crossed with homozygous wild-type mice, a 1:1 ratio of yellow and dark grey offspring were obtained. This indicated that the yellow mutation is dominant, and all the parental yellow mice were heterozygotes for the mutant allele.
By mating two yellow mice, Cuénot expected to observe a usual 1:2:1 Mendelian ratio of homozygous agouti to heterozygous yellow to homozygous yellow. Instead, he always observed a 1:2 ratio of agouti to yellow mice. He was unable to produce any mice that were homozygous for the yellow agouti allele.
It was not until 1910 that W. E. Castle and C. C. Little confirmed Cuénot's work, further demonstrating that one quarter of the offspring were dying during embryonic development. This was the first documented example of a recessive lethal allele.
Types of lethal allele
Recessive lethals
A pair of identical alleles that |
https://en.wikipedia.org/wiki/Grundy%27s%20game | Grundy's game is a two-player mathematical game of strategy. The starting configuration is a single heap of objects, and the two players take turn splitting a single heap into two heaps of different sizes. The game ends when only heaps of size two and smaller remain, none of which can be split unequally. The game is usually played as a normal play game, which means that the last person who can make an allowed move wins.
Illustration
A normal play game starting with a single heap of 8 is a win for the first player provided they start by splitting the heap into heaps of 7 and 1:
player 1: 8 → 7+1
Player 2 now has three choices: splitting the 7-heap into 6 + 1, 5 + 2, or 4 + 3. In each of these cases, player 1 can ensure that on the next move he hands back to his opponent a heap of size 4 plus heaps of size 2 and smaller:
player 2: 7+1 → 6+1+1 player 2: 7+1 → 5+2+1 player 2: 7+1 → 4+3+1
player 1: 6+1+1 → 4+2+1+1 player 1: 5+2+1 → 4+1+2+1 player 1: 4+3+1 → 4+2+1+1
Now player 2 has to split the 4-heap into 3 + 1, and player 1 subsequently splits the 3-heap into 2 + 1:
player 2: 4+2+1+1 → 3+1+2+1+1
player 1: 3+1+2+1+1 → 2+1+1+2+1+1
player 2 has no moves left and loses
Mathematical theory
The game can be analysed using the Sprague–Grundy theorem. This requires the heap sizes in the game to be mapped onto equivalent nim heap sizes. This mapping is captured in the On-Line Encyclopedia of Integer Sequences as :
Heap size : 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 ...
Equivalent Nim heap : 0 0 0 1 0 2 1 0 2 1 0 2 1 3 2 1 3 2 4 3 0 ...
Using this mapping, the strategy for playing the game Nim can also be used for Grundy's game. Whether the sequence of nim-values of Grundy's game ever becomes periodic is an unsolved problem. Elwyn Berlekamp, John Horton Conway and Richard Guy have conjectured that the sequence does become periodic eventually, but despite the calculation of the firs |
https://en.wikipedia.org/wiki/Tomotherapy | Tomotherapy is a type of radiation therapy treatment machine. In tomotherapy a thin radiation beam is modulated as it rotates around the patient, while they are moved through the bore of the machine. The name comes from the use of a strip-shaped beam, so that only one “slice” (Greek prefix “tomo-”) of the target is exposed at any one time by the radiation. The external appearance of the system and movement of the radiation source and patient can be considered analogous to a CT scanner (computed tomography), which uses lower doses of radiation for imaging. Like a conventional machine used for X-ray external beam radiotherapy (often referred to as a linear accelerator or linac, their main component), a linear accelerator generates the radiation beam, but the external appearance of the machine, the patient positioning, and treatment delivery is different. Conventional linacs do not work on a slice-by-slice basis but typically have a large area beam which can also be resized and modulated.
General principles
The treatment field's length (the width of the radiation slice) is adjustable using collimator jaws. In static-jaw delivery, the field length remains constant during a treatment. In dynamic-jaw delivery, the field length changes so that it begins and ends at its minimum setting.
Tomotherapy treatment times vary compared to normal radiation therapy treatment times. Tomotherapy treatment times can be as low as 6.5 minutes for common prostate treatment, excluding extra time for imaging. Modern tomotherapy and conventional linac systems incorporate one or both of megavoltage X-ray or kilovoltage X-ray imaging systems, enabling image-guided radiation therapy (IMRT). In tomotherapy, images are acquired in a very similar manner to a CT scanner, thanks to their closely related design.
There are few head-to-head comparisons of tomotherapy and other IMRT techniques, however there is some evidence that a conventional linac using VMAT can provide faster treatment whereas to |
https://en.wikipedia.org/wiki/TICAM1 | TIR domain containing adaptor molecule 1 (TICAM1; formerly known as TIR-domain-containing adapter-inducing interferon-β or TRIF) is an adapter in responding to activation of toll-like receptors (TLRs). It mediates the rather delayed cascade of two TLR-associated signaling cascades, where the other one is dependent upon a MyD88 adapter.
Toll-like receptors (TLRs) recognize specific components of microbial invaders and activate an immune response to these pathogens. After these receptors recognize highly conserved pathogenic patterns, a downstream signaling cascade is activated in order to stimulate the release of inflammatory cytokines and chemokines as well as to upregulate the expression of immune cells. All TLRs have a TIR domain that initiates the signaling cascade through TIR adapters. Adapters are platforms that organize downstream signaling cascades leading to a specific cellular response after exposure to a given pathogen.
Structure
TICAM1 is primarily active in the spleen and is often regulated when MyD88 is deficient in the liver, indicating organ-specific regulation of signaling pathways. Curiously, there is a lack of redundancy within the TLR4 signaling pathway that leads to microbial evasion of immune response in the host after mutations occur within intermediates of the pathway. Three TRAF-binding motifs present in the amino terminal region of TICAM1 are necessary for association with TRAF6. Destruction of these motifs reduced the activation of NF-κB, a transcription factor that is also activated by the carboxy-terminal domain of TICAM1 in the upregulation of cytokines and co-stimulatory immune molecules. This domain recruits receptor-interacting protein (RIP1) and RIP3 through the RIP homotypic interaction motif. Cells deficient for RIP1 gene display attenuated TLR3 activation of NF-κB, indicating the use of the RIP1 gene in downstream TICAM1 activation, in contrast to other TLRs that use IRAK protein for the activation of NF-κB.
Areas of researc |
https://en.wikipedia.org/wiki/CT%20pulmonary%20angiogram | A CT pulmonary angiogram (CTPA) is a medical diagnostic test that employs computed tomography (CT) angiography to obtain an image of the pulmonary arteries. Its main use is to diagnose pulmonary embolism (PE). It is a preferred choice of imaging in the diagnosis of PE due to its minimally invasive nature for the patient, whose only requirement for the scan is an intravenous line.
Modern MDCT (multi-detector CT) scanners are able to deliver images of sufficient resolution within a short time period, such that CTPA has now supplanted previous methods of testing, such as direct pulmonary angiography, as the gold standard for diagnosis of pulmonary embolism.
The patient receives an intravenous injection of an iodine-containing contrast agent at a high-rate using an injector pump. Images are acquired with the maximum intensity of radio-opaque contrast in the pulmonary arteries. This can be done using bolus tracking.
A normal CTPA scan will show the contrast filling the pulmonary vessels, appearing as bright white. Any mass filling defects, such as an embolus, will appear dark in place of the contrast, filling/blocking the space where blood should be flowing into the lungs.
Diagnostic use
CTPA was introduced in the 1990s as an alternative to ventilation/perfusion scanning (V/Q scan), which relies on radionuclide imaging of the blood vessels of the lung. It is regarded as a highly sensitive and specific test for pulmonary embolism.
CTPA is typically only requested if pulmonary embolism is suspected clinically. If the probability of PE is considered low, a blood test called D-dimer may be requested. If this is negative and risk of a PE is considered negligible, then CTPA or other scans are generally not performed. Most patients will have undergone a chest X-ray before CTPA is requested.
After initial concern that CTPA would miss smaller emboli, a 2007 study comparing CTPA directly with V/Q scanning found that CTPA identified more emboli without increasing the risk of |
https://en.wikipedia.org/wiki/CWP1 | Cell Wall Protein 1 (CWP1) is a gene of Saccharomyces cerevisiae and the Saccharomyces cerevisiae-Saccharomyces bayanus hybrid, Saccharomyces pastorianus. It is closely related to the CWP2 gene and produces a small protein associated with the budding scar, known as cwp1p. |
https://en.wikipedia.org/wiki/Rank%20product | The rank product is a biologically motivated test for the detection of differentially expressed genes in replicated microarray experiments.
It is a simple non-parametric statistical method based on ranks of fold changes. In addition to its use in expression profiling, it can be used to combine ranked lists in various application domains, including proteomics, metabolomics, statistical meta-analysis, and general feature selection.
Calculation of the rank product
Given n genes and k replicates, let the rank of gene g in the i-th replicate.
Compute the rank product via the geometric mean:
Determination of significance levels
Simple permutation-based estimation is used to determine how likely a given RP value or better is observed in a random experiment.
generate p permutations of k rank lists of length n.
calculate the rank products of the n genes in the p permutations.
count how many times the rank products of the genes in the permutations are smaller or equal to the observed rank product. Set c to this value.
calculate the average expected value for the rank product by: .
calculate the percentage of false positives as : where is the rank of gene g in a list of all n genes sorted by increasing .
Exact probability distribution and accurate approximation
Permutation re-sampling requires a computationally demanding number of permutations to get reliable estimates of the p-values for the most differentially expressed genes, if n is large. Eisinga, Breitling and Heskes (2013) provide the exact probability mass distribution of the rank product statistic. Calculation of the exact p-values offers a substantial improvement over permutation approximation, most significantly for that part of the distribution rank product analysis is most interested in, i.e., the thin right tail. However, exact statistical significance of large rank products may take unacceptable long amounts of time to compute. Heskes, Eisinga and Breitling (2014) provide a method to determine acc |
https://en.wikipedia.org/wiki/Octanoyl-CoA | Octanoyl-coenzyme A is the endpoint of beta oxidation in peroxisomes. It is produced alongside acetyl-CoA and transferred to the mitochondria to be further oxidized into acetyl-CoA.
See also
Caprylic acid, the eight-carbon saturated fatty acid known by the systematic name octanoic acid. |
https://en.wikipedia.org/wiki/GemIdent | GemIdent is an interactive image recognition program that identifies regions of interest in images and photographs. It is specifically designed for images with few colors, where the objects of interest look alike with small variation. For example, color image segmentation of:
Oranges from a tree
Stained cells from microscopic images
GemIdent also packages data analysis tools to investigate spatial relationships among the objects identified.
History
GemIdent was developed at Stanford University by Adam Kapelner from June, 2006 until January, 2007 in the lab of Dr. Peter Lee under the tutelage of Professor Susan Holmes. The concept was inspired by data Kohrt et al. who analyzed immune profiles of lymph nodes in breast cancer patients. Hence, GemIdent works well when identifying cells in IHC-stained tissue imaged via automated light microscopy when the nuclear background stain and membrane/cytoplasmic stain are well-defined. In 2008, it was adapted to support multispectral imaging techniques.
Methodology
GemIdent uses supervised learning to perform automated
identification of regions of interest in the images. Therefore, the user must do a substantial amount of work first supplying the relevant colors, then pointing out examples of the objects or regions themselves as well as negatives (training set creation).
When a user clicks on a pixel, many scores are generated using the surrounding color information via Mahalanobis Ring Score attribute generation (read the JSS paper for a detailed exposition). These scores are then used to build a random forest machine-learning classifier which will then classify pixels in any given image.
After classification, there may be mistakes. The user can return to training and point out the specific mistakes and then reclassify. These training-classifying-retraining-reclassifying iterations (considered interactive boosting) can result in a highly accurate segmentation.
Recent applications
In 2010, Setiadi et al. analyzed hist |
https://en.wikipedia.org/wiki/Regen%20und%20Meer | "" () is a song by German band Juli. It was written by band members Jonas Pfetzing and Eva Briegel along with singer Diane Weigmann for their debut album, Es ist Juli (2004), while production was helmed by O.L.A.F. Opal.
Formats and track listings
Charts |
https://en.wikipedia.org/wiki/Methylglyoxal%20pathway | The methylglyoxal pathway is an offshoot of glycolysis found in some prokaryotes, which converts glucose into methylglyoxal and then into pyruvate. However unlike glycolysis the methylglyoxal pathway does not produce adenosine triphosphate, ATP. The pathway is named after the substrate methylglyoxal which has three carbons and two carbonyl groups located on the 1st carbon and one on the 2nd carbon. Methylglyoxal is, however, a reactive aldehyde that is very toxic to cells, it can inhibit growth in E. coli at milimolar concentrations. The excessive intake of glucose by a cell is the most important process for the activation of the methylglyoxal pathway.
The Methylglyoxal pathway
The methylglyoxal pathway is activated by the increased intercellular uptake of carbon containing molecules such as glucose, glucose-6-phosphate, lactate, or glycerol. Methylglyoxal is formed from dihydroxyacetone phosphate (DHAP) by the enzyme methylglyoxal synthase, giving off a phosphate group.
Methylglyoxal is then converted into two different products, either D-lactate, and L-lactate. Methylglyoxal reductase and aldehyde dehydrogenase convert methylglyoxal into lactaldehyde and, eventually, L-lactate. If methylglyoxal enters the glyoxylase pathway, it is converted into lactoylguatathione and eventually D-lactate. Both D-lactate, and L-lactate are then converted into pyruvate. The pyruvate that is created most often goes on to enter the Krebs cycle (Weber 711–13).
Enzymes and regulation
The potentially hazardous effects of methylglyoxal require regulation of the reactions with this substrate. Synthesis of methylglyoxal is regulated by levels of DHAP and phosphate concentrations. High concentrations of DHAP encourage methylglyoxal synthase to produce methylglyoxal, while high phosphate concentrations inhibit the enzyme, and therefore the production of more methylglyoxal. The enzyme triose phosphate isomerase affects the levels of DHAP by converting glyceraldehyde 3-phosphat |
https://en.wikipedia.org/wiki/Gun%20chronograph | A ballistic chronograph or gun chronograph is a measuring instrument used to measure the velocity of a projectile in flight, typically fired from a gun.
History
Benjamin Robins (1707–1751) invented the ballistic pendulum that measures the momentum of the projectile fired by a gun. Dividing the momentum by the projectile mass gives the velocity. Robbins published his results as New Principles of Gunnery in 1742. The ballistic pendulum could make only one measurement per firing because the device catches the projectile. The gun's accuracy also limited how far down range a measurement could be made.
Alessandro Vittorio Papacino d'Antoni published results in 1765 using a wheel chronometer. This used a horizontal spinning wheel with a vertical paper mounted on the rim. The bullet was fired across the diameter of the wheel so that it pierced the paper on both sides, and the angular difference along with the rotation speed of the wheel was used to compute the bullet velocity.
An early chronograph that measures velocity directly was built in 1804 by Grobert, a colonel in the French Army. This used a rapidly rotating axle with two disks mounted on it about 13 feet apart. The bullet was fired parallel to the axle, and the angular displacement of the holes in the two disks, together with the rotational speed of the axle, yielded the bullet velocity.
describes Bashforth's chronograph that could make many measurements over long distances:
In 1865 the Rev. Francis Bashforth, M. A., who had then been recently appointed Professor of Applied Mathematics to the advanced class of artillery officers at Woolwich, began a series of experiments for determining the resistance of the air to the motion of both spherical and oblong projectiles, which he continued from time to time until 1880. As the instruments then in use for measuring velocities were incapable of giving the times occupied by a shot in passing over a series of successive equal spaces, he began his labors by inve |
https://en.wikipedia.org/wiki/Meta-Certificate%20Working%20Group | The Meta-Certificate Working Group (MCWG), also called the Meta-Certificate Group (MCG), was an Internet work group on information security.
The MCWG was founded by Ed Gerck in 1997 and had participants from 26 countries. The discussions were public as in a list server but with a privacy innovation—the participants' names and email addresses were anonymized. This privacy feature, which any participant could break voluntarily by simply disclosing name and email address in the list, allowed the discussion to proceed on a technical level more easily, with less ad hominem attacks. This also allowed unwitting competitors to collaborate, creating an open climate.
The work developed by the MCWG has been applied to Internet standards and practical developments in several work groups and companies worldwide. |
https://en.wikipedia.org/wiki/Euclidean%20shortest%20path | The Euclidean shortest path problem is a problem in computational geometry: given a set of polyhedral obstacles in a Euclidean space, and two points, find the shortest path between the points that does not intersect any of the obstacles.
Two dimensions
In two dimensions, the problem can be solved in polynomial time in a model of computation allowing addition and comparisons of real numbers, despite theoretical difficulties involving the numerical precision needed to perform such calculations. These algorithms are based on two different principles, either performing a shortest path algorithm such as Dijkstra's algorithm on a visibility graph derived from the obstacles or (in an approach called the continuous Dijkstra method) propagating a wavefront from one of the points until it meets the other.
Higher dimensions
In three (and higher) dimensions the problem is NP-hard in the general case, but there exist efficient approximation algorithms that run in polynomial time based on the idea of finding a suitable sample of points on the obstacle edges and performing a visibility graph calculation using these sample points.
There are many results on computing shortest paths which stays on a polyhedral surface. Given two points s and t, say on the surface
of a convex polyhedron, the problem is to compute a shortest path that never leaves the surface and connects s with t.
This is a generalization of the problem from 2-dimension but it is much easier than the 3-dimensional problem.
Variants
There are variations of this problem, where the obstacles are weighted, i.e., one can go through an obstacle, but it incurs
an extra cost to go through an obstacle. The standard problem is the special case where the obstacles have infinite weight. This is
termed as the weighted region problem in the literature.
See also
Shortest path problem, in a graph of edges and vertices
Any-angle path planning, in a grid space
Notes |
https://en.wikipedia.org/wiki/MakeHuman | MakeHuman is a free and open source 3D computer graphics middleware designed for the prototyping of photorealistic humanoids. It is developed by a community of programmers, artists, and academics interested in 3D character modeling.
Technology
MakeHuman is developed using 3D morphing technology. Starting from a standard (unique) androgynous human base mesh, it can be transformed into a great variety of characters (male and female), mixing them with linear interpolation. For example, given the four main morphing targets (baby, teen, young, old), it is possible to obtain all the intermediate shapes.
Using this technology, with a large database of morphing targets, it's virtually possible to reproduce any character. It uses a very simple GUI in order to access and easily handle hundreds of morphings. The MakeHuman approach is to use sliders with common parameters like height, weight, gender, ethnicity and muscularity. In order to make it available on all major operating systems, beginning from 1.0 alpha 8 it's developed in Python using OpenGL and Qt, with an architecture fully realized with plugins.
The tool is specifically designed for the modeling of virtual 3D human models, with a simple and complete pose system that includes the simulation of muscular movement. The interface is easy to use, with fast and intuitive access to the numerous parameters required in modeling the human form.
The development of MakeHuman is derived from a detailed technical and artistic study of the morphological characteristics of the human body. The work deals with morphing, using linear interpolation of both translation and rotation. With these two methods, together with a simple calculation of a form factor and an algorithm of mesh relaxing, it is possible to achieve results such as the simulation of muscular movement that accompanies the rotation of the limbs.
License
MakeHuman is free and open-source, with the source code and database released under the GNU Affero GPL. Models e |
https://en.wikipedia.org/wiki/Accurate%20Miniatures | Accurate Miniatures is an American manufacturer of scale plastic model kits. It is owned by Collins-Habovick, LLC and is located in Concord, North Carolina, United States. Their products primarily consist plastic model airplane kits from World War II, though they also make model kits of planes and automobiles from other eras.
History
The original Accurate Miniatures was a Charlotte, North Carolina based plastic model company that began business in the mid-1990s. They filed for bankruptcy in June 2001. Later that year, Accurate Miniatures was purchased from the original owners by Hobby Investors LLC, now called Collins-Habovick, LLC. The transfer included the sale of the company name, logo, inventory, and intellectual property. Paul Bedford, former general manager of the original Accurate Miniatures, claims the deal was part cash and part debt assumption.
In July 2001, Accurate Miniatures, in an attempt to get out of debt, prepared to sell as much as 70% of their tooling (model molds) to the Bologna, Italy based Italeri. Some of the molds included molds for the Avenger, Dauntless, Grumman F3F, Mustang, Stormovik, and Yak kits. However, the sale to Hobby Investors LLC nullified this deal.
Unseen to Collins-Habovick was the financial disaster left by the previous management. When the previous management ceased operation, substantial debt remained behind. Mold sets like the B-25 and F-3F were not paid off completely, and mold commitments for the NASCAR stock car, SB2U, and an R-4 were not funded at all even though a fair amount of tooling had been complete. All of this (not including unpaid artists, printers, and many others) had to be overcome before anything else could be achieved.
Only through the diligent work and patience of the small staff was Accurate Miniatures able to be resurrected to become a successful company that is praised by model builders for their high-quality kits and attention to detail.
Product lines
Aircraft
Accurate Miniatures produces model |
https://en.wikipedia.org/wiki/Isothermal%20transformation%20diagram | Isothermal transformation diagrams (also known as time-temperature-transformation (TTT) diagrams) are plots of temperature versus time (usually on a logarithmic scale). They are generated from percentage transformation-vs time measurements, and are useful for understanding the transformations of an alloy steel at elevated temperatures.
An isothermal transformation diagram is only valid for one specific composition of material, and only if the temperature is held constant during the transformation, and strictly with rapid cooling to that temperature. Though usually used to represent transformation kinetics for steels, they also can be used to describe the kinetics of crystallization in ceramic or other materials. Time-temperature-precipitation diagrams and time-temperature-embrittlement diagrams have also been used to represent kinetic changes in steels.
Isothermal transformation (IT) diagram or the C-curve is associated with mechanical properties, microconstituents/microstructures, and heat treatments in carbon steels. Diffusional transformations like austenite transforming to a cementite and ferrite mixture can be explained using the sigmoidal curve; for example the beginning of pearlitic transformation is represented by the pearlite start (Ps) curve. This transformation is complete at Pf curve. Nucleation requires an incubation time. The rate of nucleation increases and the rate of microconstituent growth decreases as the temperature decreases from the liquidus temperature reaching a maximum at the bay or nose of the curve. Thereafter, the decrease in diffusion rate due to low temperature offsets the effect of increased driving force due to greater difference in free energy. As a result of the transformation, the microconstituents, pearlite and bainite, form; pearlite forms at higher temperatures and bainite at lower.
Austenite is slightly undercooled when quenched below Eutectoid temperature. When given more time, stable microconstituents can form: ferrite |
https://en.wikipedia.org/wiki/Photobiotin | Photobiotin is a derivative of biotin used as a biochemical tool. It is composed of a biotin group, a linker group, and a photoactivatable aryl azide group.
The photoactivatable group provides nonspecific labeling of proteins, DNA and RNA probes or other molecules. Biotinylation of DNA and RNA with photoactivatable biotin is easier and less expensive than enzymatic methods since the DNA and RNA does not degrade. Photobiotin is most effectively activated by light at 260-475 nm. |
https://en.wikipedia.org/wiki/Bimbo%20%28comics%29 | Bimbo was a British comic book magazine aimed at children in nursery school. It ran from 1961 until 1972 and was published by D.C. Thomson & Co. The magazine was named after its main feature Bimbo, which was a comic strip about a little boy.
The magazine was comparable to the magazine Little Star. Bimbo annuals continued to be published until the 1980s.
Characters
Bimbo drawn by Bob Dewar
Tom Thumb drawn by Dudley D. Watkins from early issues of The Beano
Patsy The Panda from the little girl's comic Twinkle.
Beezer star Baby Crockett drawn by Bill Ritchie |
https://en.wikipedia.org/wiki/XIAP | X-linked inhibitor of apoptosis protein (XIAP), also known as inhibitor of apoptosis protein 3 (IAP3) and baculoviral IAP repeat-containing protein 4 (BIRC4), is a protein that stops apoptotic cell death. In humans, this protein (XIAP) is produced by a gene named XIAP gene located on the X chromosome.
XIAP is a member of the inhibitor of apoptosis family of proteins (IAP). IAPs were initially identified in baculoviruses, but XIAP is one of the homologous proteins found in mammals. It is so called because it was first discovered by a 273 base pair site on the X chromosome. The protein is also called human IAP-like Protein (hILP), because it is not as well conserved as the human IAPS: hIAP-1 and hIAP-2. XIAP is the most potent human IAP protein currently identified.
Discovery
Neuronal apoptosis inhibitor protein (NAIP) was the first homolog to baculoviral IAPs that was identified in humans. With the sequencing data of NIAP, the gene sequence for a RING zinc-finger domain was discovered at site Xq24-25. Using PCR and cloning, three BIR domains and a RING finger were found on the protein, which became known as X-linked Inhibitor of Apoptosis Protein. The transcript size of Xiap is 9.0kb, with an open reading frame of 1.8kb. Xiap mRNA has been observed in all human adult and fetal tissues "except peripheral blood leukocytes". The XIAP sequences led to the discovery of other members of the IAP family.
Structure
XIAP consists of three major types of structural elements (domains). Firstly, there is the baculoviral IAP repeat (BIR) domain consisting of approximately 70 amino acids, which characterizes all IAP. Secondly, there is a UBA domain, which allows XIAP to bind to ubiquitin. Thirdly, there is a zinc-binding domain, or a "carboxy-terminal RING Finger". XIAP has been characterized with three amino-terminal BIR domains followed by one UBA domain and finally one RING domain. Between the BIR-1 and BIR-2 domains, there is a linker-BIR-2 region that is thought to contai |
https://en.wikipedia.org/wiki/Effective%20dimension | In mathematics, effective dimension is a modification of Hausdorff dimension and other fractal dimensions that places it in a computability theory setting. There are several variations (various notions of effective dimension) of which the most common is effective Hausdorff dimension. Dimension, in mathematics, is a particular way of describing the size of an object (contrasting with measure and other, different, notions of size). Hausdorff dimension generalizes the well-known integer dimensions assigned to points, lines, planes, etc. by allowing one to distinguish between objects of intermediate size between these integer-dimensional objects. For example, fractal subsets of the plane may have intermediate dimension between 1 and 2, as they are "larger" than lines or curves, and yet "smaller" than filled circles or rectangles. Effective dimension modifies Hausdorff dimension by requiring that objects with small effective dimension be not only small but also locatable (or partially locatable) in a computable sense. As such, objects with large Hausdorff dimension also have large effective dimension, and objects with small effective dimension have small Hausdorff dimension, but an object can have small Hausdorff but large effective dimension. An example is an algorithmically random point on a line, which has Hausdorff dimension 0 (since it is a point) but effective dimension 1 (because, roughly speaking, it can't be effectively localized any better than a small interval, which has Hausdorff dimension 1).
Rigorous definitions
This article will define effective dimension for subsets of Cantor space 2ω; closely related definitions exist for subsets of Euclidean space Rn. We will move freely between considering a set X of natural numbers, the infinite sequence given by the characteristic function of X, and the real number with binary expansion 0.X.
Martingales and other gales
A martingale on Cantor space 2ω is a function d: 2ω → R≥ 0 from Cantor space to nonnegative r |
https://en.wikipedia.org/wiki/Armillaria%20luteobubalina | Armillaria luteobubalina, commonly known as the Australian honey fungus, is a species of mushroom in the family Physalacriaceae. Widely distributed in southern Australia, the fungus is responsible for a disease known as Armillaria root rot, a primary cause of Eucalyptus tree death and forest dieback. It is the most pathogenic and widespread of the six Armillaria species found in Australia. The fungus has also been collected in Argentina and Chile. Fruit bodies have cream- to tan-coloured caps that grow up to in diameter and stems that measure up to long by thick. The fruit bodies, which appear at the base of infected trees and other woody plants in autumn (March–April), are edible, but require cooking to remove the bitter taste. The fungus is dispersed through spores produced on gills on the underside of the caps, and also by growing vegetatively through the root systems of host trees. The ability of the fungus to spread vegetatively is facilitated by an aerating system that allows it to efficiently diffuse oxygen through rhizomorphs—rootlike structures made of dense masses of hyphae.
Armillaria luteobubalina was first described in 1978, after having been discovered several years earlier growing in a Eucalyptus plantation in southeastern Australia. It distinguished itself from other known Australian Armillaria species by its aggressive pathogenicity. It may take years for infected trees to show signs of disease, leading to an underestimation of disease prevalence. Studies show that the spread of disease in eucalypt forests is associated with infected stumps left following logging operations. Although several methods have been suggested to control the spread of disease, they are largely economically or environmentally unfeasible. Phylogenetic analyses have determined that A. luteobubalina is closely related to A. montagnei and that both of these species are in turn closely related to the Brazilian species A. paulensis. The distribution of A. luteobubalina sugges |
https://en.wikipedia.org/wiki/Unate%20function | A unate function is a type of boolean function which has monotonic properties.
They have been studied extensively in switching theory.
A function is said to be positive unate in
if for all possible values of ,
Likewise, it is negative unate in if
If for every f is either positive or negative unate in the variable then it is said to be unate (note that some may be positive unate and some negative unate to satisfy the definition of unate function). A function is binate if it is not unate (i.e., is neither positive unate nor negative unate in at least one of its variables).
For example, the logical disjunction function or with boolean values used for true (1) and false (0) is positive unate. Conversely, Exclusive or is non-unate, because the transition from 0 to 1 on input x0 is both positive unate and negative unate, depending on the input value on x1.
Positive unateness can also be considered as passing the same slope (no change in the input) and negative unate is passing the opposite slope....
non unate is dependence on more than one input (of same or different slopes)
Syntax (logic) |
https://en.wikipedia.org/wiki/Van%20der%20Waals%20molecule | A Van der Waals molecule is a weakly bound complex of atoms or molecules held together by intermolecular attractions such as Van der Waals forces or by hydrogen bonds.
The name originated in the beginning of the 1970s when stable molecular clusters were regularly observed in molecular beam microwave spectroscopy.
Examples
Examples of well-studied vdW molecules are Ar2, H2-Ar, H2O-Ar, benzene-Ar, (H2O)2, and (HF)2.
Others include the largest diatomic molecule: He2 and LiHe.
Supersonic beam spectroscopy
In (supersonic) molecular beams temperatures are very low (usually less than 5 K). At these low temperatures Van der Waals (vdW) molecules are stable and can be investigated by microwave, far-infrared spectroscopy and other modes of spectroscopy.
Also in cold equilibrium gases vdW molecules are formed, albeit in small, temperature dependent concentrations. Rotational and vibrational transitions in vdW molecules have been observed in gases, mainly by UV and IR spectroscopy.
Van der Waals molecules are usually very non-rigid and different versions are separated by low energy barriers, so that tunneling splittings, observable in far-infrared spectra, are relatively large.
Thus, in the far-infrared one may observe intermolecular vibrations, rotations, and tunneling motions of Van der Waals molecules.
The VRT spectroscopic study of Van der Waals molecules is one of the most direct routes to the understanding of intermolecular forces.
See also
Van der Waals radius
Van der Waals strain
Van der Waals surface
–articles about specific chemicals
Researchers active in this field:
Donald Levy
Richard J. Saykally
Richard Smalley
William Klemperer |
https://en.wikipedia.org/wiki/Smart%20transducer | A smart transducer is an analog or digital transducer, actuator or sensor combined with a processing unit and a communication interface.
As sensors and actuators become more complex they provide support for various modes of operation and interfacing. Some applications require additionally fault-tolerance and distributed computing. Such high-level functionality can be achieved by adding an embedded microcontroller to the classical sensor/actuator, which increases the ability to cope with complexity at a fair price. Typically, these on-board technologies in smart sensors are used for digital processing, either frequency-to-code or analog-to-digital conversations, interfacing functions and calculations. Interfacing functions include decision-making tools like self-adaption, self-diagnostics and self-identification functions, but also to control how long and when the sensor will be fully awake, to minimize power consumption and to decide when to dump and store data.
They are often made using CMOS, VLSI technology and may contain MEMS devices leading to lower cost. They may provide full digital outputs for easier interface or they may provide quasi-digital outputs like pulse-width modulation. In the machine vision field, a single compact unit that combines the imaging functions and the complete image processing functions is often called a smart sensor.
Smart sensors are a crucial element in the phenomenon Internet of Things (IoT). Within such a network, multiple physical vehicles and devices are embedded with sensors, software and electronics. Data will be collected and shared for better integration between digital environments and the physical world. The connectivity between sensors is an important requirement for an IoT innovation to perform well. Interoperability can therefore be seen as an consequence of connectivity. The sensors work and complement each other.
Improvement over traditional sensors
The key features of smart sensors as part of the IoT that differ |
https://en.wikipedia.org/wiki/Spo11 | Spo11 is a protein that in humans is encoded by the SPO11 gene. Spo11, in a complex with mTopVIB, creates double strand breaks to initiate meiotic recombination. Its active site contains a tyrosine which ligates and dissociates with DNA to promote break formation. One Spo11 protein is involved per strand of DNA, thus two Spo11 proteins are involved in each double stranded break event.
Genetic exchange between two DNA molecules by homologous recombination begins with a break in both strands of DNA—called a double-strand break—and recombination is started by an endonuclease enzyme that cuts the DNA molecule that "receives" the exchanged DNA. In meiosis the enzyme is SPO11, which is related to DNA topoisomerases. Topoisomerases change DNA by transiently breaking one or both strands, passing the unbroken DNA strand or strands through the break and repairing the break; the broken ends of the DNA are covalently linked to topoisomerase. SPO11 is similarly attached to the DNA when it forms double-strand breaks during meiosis.
Meiotic recombination
SPO11 is considered to play a predominant role in initiating meiotic recombination. However, recombination may also occur by alternative SPO11-independent mechanisms that can be studied experimentally using spo11 mutants.
In the budding yeast Saccharomyces cerevisiae, the meiotic defects in recombination and chromosome disjunction of spo11 mutants are alleviated by X-irradiation. This finding indicates that X-ray induced DNA damages can initiate crossover recombination leading to proper disjunction independently of SPO11.
In the worm Caenorhabditis elegans, a homolog of spo11 is ordinarily employed in the initiation of meiotic recombination. However, radiation induced-breaks can also initiate recombination in mutants deleted for this spo11 homolog.
Deamination of cytosine resulting in the dU:dG mismatch is one of the most common single-base-altering lesions in non-replicating DNA. Spo11 mutants of the fission yeast Schi |
https://en.wikipedia.org/wiki/Caralluma%20edulis | Caralluma edulis is a succulent species in the plant family Apocynaceae, native to India and Pakistan.
The leaves and stem are eaten in North Africa. |
https://en.wikipedia.org/wiki/Genetic%20Information%20Nondiscrimination%20Act | The Genetic Information Nondiscrimination Act of 2008 (, GINA ), is an Act of Congress in the United States designed to prohibit some types of genetic discrimination. The act bars the use of genetic information in health insurance and employment: it prohibits group health plans and health insurers from denying coverage to a healthy individual or charging that person higher premiums based solely on a genetic predisposition to developing a disease in the future, and it bars employers from using individuals' genetic information when making hiring, firing, job placement, or promotion decisions. Senator Ted Kennedy called it the "first major new civil rights bill of the new century." The Act contains amendments to the Employee Retirement Income Security Act of 1974 and the Internal Revenue Code of 1986.
In 2008, on April 24 passed the Senate 95-0. The bill was then sent back to the House of Representatives and passed 414-1 on May 1; the lone dissenter was Congressman Ron Paul. President George W. Bush signed the bill into law on May 21, 2008.
Legislative history
Preliminary bills
In the 104th Congress (1995–1996) several related bills were introduced.
The Genetic Privacy and Nondiscrimination Act of 1996, : Sen. Mark Hatfield and : Rep. Clifford Stearns
The Genetic Fairness Act of 1996, : Sen. Dianne Feinstein
The Genetic Information Nondiscrimination in Health Insurance Act of 1995, : Rep. Louise Slaughter and : Sen. Olympia Snowe
Genetic Confidentiality and Nondiscrimination Act of 1996, : Sen. Pete Domenici
In 1997, the Coalition for Genetic Fairness (CGF) was formed by several patient and civil rights groups to spearhead genetic nondiscrimination legislation on Capitol Hill. The CGF became the primary non-governmental driver of Federal genetic non-discrimination legislation.
In 2003, GINA was introduced as , by Louise Slaughter, D-NY, and as by Senator Snowe, R-ME.
In 2005, it was proposed as by Representative Biggert, R-IL, and as by Senator Snowe, |
https://en.wikipedia.org/wiki/Rotational%20diffusion | Rotational diffusion is the rotational movement which acts upon any object such as particles, molecules, atoms when present in a fluid, by random changes in their orientations.
Whilst the directions and intensities of these changes are statistically random, they do not arise randomly and are instead the result of interactions between particles. One example occurs in colloids, where relatively large insoluble particles are suspended in a greater amount of fluid. The changes in orientation occur from collisions between the particle and the many molecules forming the fluid surrounding the particle, which each transfer kinetic energy to the particle, and as such can be considered random due to the varied speeds and amounts of fluid molecules incident on each individual particle at any given time.
The analogue to translational diffusion which determines the particle's position in space, rotational diffusion randomises the orientation of any particle it acts on.
Anything in a solution will experience rotational diffusion, from the microscopic scale where individual atoms may have an effect on each other, to the macroscopic scale.
Applications
Rotational diffusion has multiple applications in chemistry and physics, and is heavily involved in many biology based fields. For example, protein-protein interaction is a vital step in the communication of biological signals. In order to communicate, the proteins must both come into contact with each other and be facing the appropriate way to interact with each other's binding site, which relies on the proteins ability to rotate.
As an example concerning physics, rotational Brownian motion in astronomy can be used to explain the orientations of the orbital planes of binary stars, as well as the seemingly random spin axes of supermassive black holes.
The random re-orientation of molecules (or larger systems) is an important process for many biophysical probes. Due to the equipartition theorem, larger molecules re-orient more s |
https://en.wikipedia.org/wiki/Molecular%20symmetry | In chemistry, molecular symmetry describes the symmetry present in molecules and the classification of these molecules according to their symmetry. Molecular symmetry is a fundamental concept in chemistry, as it can be used to predict or explain many of a molecule's chemical properties, such as whether or not it has a dipole moment, as well as its allowed spectroscopic transitions. To do this it is necessary to use group theory. This involves classifying the states of the molecule using the irreducible representations
from the character table of the symmetry group of the molecule. Symmetry is useful in the study of molecular orbitals, with applications to the Hückel method, to ligand field theory, and to the Woodward-Hoffmann rules. Many university level textbooks on physical chemistry, quantum chemistry, spectroscopy and inorganic chemistry discuss symmetry. Another framework on a larger scale is the use of crystal systems to describe crystallographic symmetry in bulk materials.
There are many techniques for determining the symmetry of a given molecule, including X-ray crystallography and various forms of spectroscopy. Spectroscopic notation is based on symmetry considerations.
Point group symmetry concepts
Elements
The point group symmetry of a molecule is defined by the presence or absence of 5 types of symmetry element.
Symmetry axis: an axis around which a rotation by results in a molecule indistinguishable from the original. This is also called an n-fold rotational axis and abbreviated Cn. Examples are the C2 axis in water and the C3 axis in ammonia. A molecule can have more than one symmetry axis; the one with the highest n is called the principal axis, and by convention is aligned with the z-axis in a Cartesian coordinate system.
Plane of symmetry: a plane of reflection through which an identical copy of the original molecule is generated. This is also called a mirror plane and abbreviated σ (sigma = Greek "s", from the German 'Spiegel' mea |
https://en.wikipedia.org/wiki/Mt.%20Olive%20Pickle%20Company | The Mount Olive Pickle Company is an American food processing company located in Mount Olive, North Carolina. The company's primary product is pickled cucumbers, but it is also a large supplier of pepper, mixed pickle, relish, and other pickled products. Mt. Olive is the largest independent pickle company in the United States and the top-selling pickle brand in the Southeastern United States, where its market share approaches 70 percent.
Facilities are all located in Mt. Olive on with of production, office, and warehouse space. The company has in excess of 1,200 brining vats and can store over of cucumbers. The company employs over 500 people which swells to over 800 during the busiest intake season each summer. In 1943, the company was one of the first in the country to offer profit sharing plans to their employees. In 1959, Mt. Olive established an employee community fund that helped support local community organizations. The Mt. Olive community fund also awards scholarships to employees' children. Each school year the company's community fund awards four scholarships for four different students at $1,500 each.
History
In the mid-1920s, Shikrey Baddour, a Lebanese immigrant from nearby Goldsboro, first saw opportunity in the wasted cucumber crops of area farmers. Baddour came up with the idea of buying the cucumbers, putting them in a brining tank, and selling the brined cucumbers, or brine stock, to other pickle firms. Baddour enlisted the aid of George Moore, a sailor from Wilmington who had worked in a Castle Hayne pickle plant. The plan didn't work the way they had envisioned, however: they had no buyers for their product.
By January 1926, a new plan was put into place through the efforts of a group of Mount Olive business people, led by Headley Morris Cox, who formally established the Mt. Olive Pickle Company, Inc. to pack and sell its own pickles. Thirty-seven original shareholders put forward $19,000 in capital to get the company started in what all |
https://en.wikipedia.org/wiki/Emodin | Emodin (6-methyl-1,3,8-trihydroxyanthraquinone) is a chemical compound, of the anthraquinone family, that can be isolated from rhubarb, buckthorn, and Japanese knotweed (Reynoutria japonica syn. Polygonum cuspidatum). Emodin is particularly abundant in the roots of the Chinese rhubarb (Rheum palmatum), knotweed and knotgrass (Polygonum cuspidatum and multiflorum) as well as Hawaii ‘au‘auko‘i cassia seeds or coffee weed (Semen cassia). It is specifically isolated from Rheum palmatum L. It is also produced by many species of fungi, including members of the genera Aspergillus, Pyrenochaeta, and Pestalotiopsis, inter alia. The common name is derived from Rheum emodi, a taxonomic synonym of Rheum australe, (Himalayan rhubarb) and synonyms include emodol, frangula emodin, rheum emodin, 3-methyl-1,6,8-trihydroxyanthraquinone, Schüttgelb (Schuttgelb), and Persian Berry Lake.
Pharmacology
Emodin is an active component of several plants used in Traditional Chinese Medicine (TCM) such as Rheum palmatum, Polygonum cuspidatum and Polygonum multiflorum. It has various actions including laxative, antibacterial and antiinflammatory effects, and has also been identified as having potential antiviral activity against coronaviruses such as SARS-CoV-2, being one of the major active components of the antiviral TCM formulation Lianhua Qingwen.
A computational study was conducted to investigate the inhibition mechanism on the formation of the Spike-ACE2 protein complex. Specifically, it is seen dose-dependent inhibition in the prevention of infection by the SARS-Cov-1 whose evidence has stimulated further investigations on SARS-Cov-2.
Emodin has been shown to inhibit the ion channel of protein 3a which could play a crucial role in the release of the virus from infected cells.
List of species
The following plant species produce emodin:
Acalypha australis
Cassia occidentalis
Cassia siamea
Frangula alnus
Glossostemon bruguieri
Kalimeris indica
Polygonum hypoleucum
Reynoutria japo |
https://en.wikipedia.org/wiki/Statistical%20interference | When two probability distributions overlap, statistical interference exists. Knowledge of the distributions can be used to determine the likelihood that one parameter exceeds another, and by how much.
This technique can be used for dimensioning of mechanical parts, determining when an applied load exceeds the strength of a structure, and in many other situations. This type of analysis can also be used to estimate the probability of failure or the frequency of failure.
Dimensional interference
Mechanical parts are usually designed to fit precisely together. For example, if a shaft is designed to have a "sliding fit" in a hole, the shaft must be a little smaller than the hole. (Traditional tolerances may suggest that all dimensions fall within those intended tolerances. A process capability study of actual production, however, may reveal normal distributions with long tails.) Both the shaft and hole sizes will usually form normal distributions with some average (arithmetic mean) and standard deviation.
With two such normal distributions, a distribution of interference can be calculated. The derived distribution will also be normal, and its average will be equal to the difference between the means of the two base distributions. The variance of the derived distribution will be the sum of the variances of the two base distributions.
This derived distribution can be used to determine how often the difference in dimensions will be less than zero (i.e., the shaft cannot fit in the hole), how often the difference will be less than the required sliding gap (the shaft fits, but too tightly), and how often the difference will be greater than the maximum acceptable gap (the shaft fits, but not tightly enough).
Physical property interference
Physical properties and the conditions of use are also inherently variable. For example, the applied load (stress) on a mechanical part may vary. The measured strength of that part (tensile strength, etc.) may also be variable. |
https://en.wikipedia.org/wiki/WCF%20Data%20Services | WCF Data Services (formerly ADO.NET Data Services, codename "Astoria") is a platform for what Microsoft calls Data Services. It is actually a combination of the runtime and a web service through which the services are exposed. It also includes the Data Services Toolkit which lets Astoria Data Services be created from within ASP.NET itself. The Astoria project was announced at MIX 2007, and the first developer preview was made available on April 30, 2007. The first CTP was made available as a part of the ASP.NET 3.5 Extensions Preview. The final version was released as part of Service Pack 1 of the .NET Framework 3.5 on August 11, 2008. The name change from ADO.NET Data Services to WCF data Services was announced at the 2009 PDC.
Overview
WCF Data Services exposes data, represented as Entity Data Model (EDM) objects, via web services accessed over HTTP. The data can be addressed using a REST-like URI. The data service, when accessed via the HTTP GET method with such a URI, will return the data. The web service can be configured to return the data in either plain XML, JSON or RDF+XML. In the initial release, formats like RSS and ATOM are not supported, though they may be in the future. In addition, using other HTTP methods like PUT, POST or DELETE, the data can be updated as well. POST can be used to create new entities, PUT for updating an entity, and DELETE for deleting an entity.
Description
Windows Communication Foundation (WCF) comes to the rescue when we find ourselves not able to achieve what we want to achieve using web services, i.e., other protocols support and even duplex communication. With WCF, we can define our service once and then configure it in such a way that it can be used via HTTP, TCP, IPC, and even Message Queues. We can consume Web Services using server side scripts (ASP.NET), JavaScript Object Notations (JSON), and even REST (Representational State Transfer).
Understanding the basics
When we say that a WCF service can be used to communica |
https://en.wikipedia.org/wiki/Dynamic%20Language%20Runtime | The Dynamic Language Runtime (DLR) from Microsoft runs on top of the Common Language Runtime (CLR) and provides computer language services for dynamic languages. These services include:
A dynamic type system, to be shared by all languages using the DLR services
Dynamic method dispatch
Dynamic code generation
Hosting API
The DLR is used to implement dynamic languages on the .NET Framework, including the IronPython and IronRuby projects.
Because the dynamic language implementations share a common underlying system, it should be easier for them to interact with one another. For example, it should be possible to use libraries from any dynamic language in any other dynamic language. In addition, the hosting API allows interoperability with statically typed CLI languages like C# and Visual Basic .NET.
History
Microsoft's Dynamic Language Runtime project was announced by Microsoft at MIX 2007.
Microsoft shipped .NET DLR 0.9 beta in November 2008, and final 0.9 in December 2008. Version 1.0 shipped in April 2010. In July 2010, Microsoft changed the license of the DLR from the Microsoft Public License to the Apache License 2.0. With the release of .NET 4, also in April 2010, DLR was incorporated into the .NET Framework itself.
The open source DLR project hosted on GitHub has a few additional features for language implementers. After the July 2010 release, there was little activity on the project for some years. This was interpreted by a Microsoft developer who worked on IronRuby as a lack of commitment from Microsoft to dynamic languages on the .NET Framework. However, there has been regular activity since 2016/17, leading to a number of improvements and upgrades.
Language implementations
In 2007, Microsoft initially planned to use the DLR for the upcoming Visual Basic 2010 (VB 10.0) and Managed JScript (ECMAScript 3.0) as well as Python and Ruby.
The DLR work on Ruby and Python resulted in IronRuby, a .NET implementation of the Ruby language, and IronPython.
|
https://en.wikipedia.org/wiki/Retinalophototroph | A retinalophototroph is one of two different types of phototrophs, and are named for retinal-binding proteins (microbial rhodopsins) they utilize for cell signaling and converting light into energy. Like all photoautotrophs, retinalophototrophs absorb photons to initiate their cellular processes. However, unlike all photoautotrophs, retinalophototrophs do not use chlorophyll or an electron transport chain to power their chemical reactions. This means retinalophototrophs are incapable of traditional carbon fixation, a fundamental photosynthetic process that transforms inorganic carbon (carbon contained in molecular compounds like carbon dioxide) into organic compounds. For this reason, experts consider them to be less efficient than their chlorophyll-using counterparts, chlorophototrophs.
Energy conversion
Retinalophototrophs achieve adequate energy conversion via a proton-motive force. In retinalophototrophs, proton-motive force is generated from rhodopsin-like proteins, primarily bacteriorhodopsin and proteorhodopsin, acting as proton pumps along a cellular membrane.
To capture photons needed for activating a protein pump, retinalophototrophs employ organic pigments known as carotenoids, namely beta-carotenoids. Beta-carotenoids present in retinalophototrophs are unusual candidates for energy conversion, but they possess high Vitamin-A activity necessary for retinaldehyde, or retinal, formation. Retinal, a chromophore molecule configured from Vitamin A, is formed when bonds between carotenoids are disrupted in a process called cleavage. Due to its acute light sensitivity, retinal is ideal for activation of proton-motive force and imparts a unique purple coloration to retinalophototrophs. Once retinal absorbs enough light, it isomerizes, thereby forcing a conformational (i.e., structural) change among the covalent bonds of the rhodopsin-like proteins. Upon activation, these proteins mimic a gateway, allowing passage of ions to create an electrochemical gradient b |
https://en.wikipedia.org/wiki/Restricted%20partial%20quotients | In mathematics, and more particularly in the analytic theory of regular continued fractions, an infinite regular continued fraction x is said to be restricted, or composed of restricted partial quotients, if the sequence of denominators of its partial quotients is bounded; that is
and there is some positive integer M such that all the (integral) partial denominators ai are less than or equal to M.
Periodic continued fractions
A regular periodic continued fraction consists of a finite initial block of partial denominators followed by a repeating block; if
then ζ is a quadratic irrational number, and its representation as a regular continued fraction is periodic. Clearly any regular periodic continued fraction consists of restricted partial quotients, since none of the partial denominators can be greater than the largest of a0 through ak+m. Historically, mathematicians studied periodic continued fractions before considering the more general concept of restricted partial quotients.
Restricted CFs and the Cantor set
The Cantor set is a set C of measure zero from which a complete interval of real numbers can be constructed by simple addition – that is, any real number from the interval can be expressed as the sum of exactly two elements of the set C. The usual proof of the existence of the Cantor set is based on the idea of punching a "hole" in the middle of an interval, then punching holes in the remaining sub-intervals, and repeating this process ad infinitum.
The process of adding one more partial quotient to a finite continued fraction is in many ways analogous to this process of "punching a hole" in an interval of real numbers. The size of the "hole" is inversely proportional to the next partial denominator chosen – if the next partial denominator is 1, the gap between successive convergents is maximized.
To make the following theorems precise we will consider CF(M), the set of restricted continued fractions whose values lie in the open interval (0, 1) and who |
https://en.wikipedia.org/wiki/Luzin%20space | In mathematics, a Luzin space (or Lusin space), named for N. N. Luzin, is an uncountable topological T1 space without isolated points in which every nowhere-dense subset is countable. There are many minor variations of this definition in use: the T1 condition can be replaced by T2 or T3, and some authors allow a countable or even arbitrary number of isolated points.
The existence of a Luzin space is independent of the axioms of ZFC. showed that the continuum hypothesis implies that a Luzin space exists.
showed that assuming Martin's axiom and the negation of the continuum hypothesis, there are no Hausdorff Luzin spaces.
In real analysis
In real analysis and descriptive set theory, a Luzin set (or Lusin set), is defined as an uncountable subset of the reals such that every uncountable subset of is nonmeager; that is, of second Baire category. Equivalently, is an uncountable set of reals that meets every first category set in only countably many points. Luzin proved that, if the continuum hypothesis holds, then every nonmeager set has a Luzin subset. Obvious properties of a Luzin set are that it must be nonmeager (otherwise the set itself is an uncountable meager subset) and of measure zero, because every set of positive measure contains a meager set that also has positive measure, and is therefore uncountable. A weakly Luzin set is an uncountable subset of a real vector space such that for any uncountable subset the set of directions between different elements of the subset is dense in the sphere of directions.
The measure-category duality provides a measure analogue of Luzin sets – sets of positive outer measure, every uncountable subset of which has positive outer measure. These sets are called Sierpiński sets, after Wacław Sierpiński. Sierpiński sets are weakly Luzin sets but are not Luzin sets.
Example of a Luzin set
Choose a collection of 2ℵ0 meager subsets of R such that every meager subset is contained in one of them. By the continuum hypothesis, |
https://en.wikipedia.org/wiki/Oocyte%20cryopreservation | Oocyte cryopreservation is a procedure to preserve a woman's eggs (oocytes). This technique has been used to enable women to postpone pregnancy to a later date – whether for medical or social reasons. Several studies have shown that most infertility problems are due to germ cell deterioration related to aging. The intention of the procedure is that the woman may choose to have the eggs thawed, fertilized, and transferred to the uterus as embryos to facilitate a pregnancy in the future. The procedure's success rate varies depending on the age of the woman, with odds being higher in younger, adult women.
Indications
Oocyte cryopreservation can increase the chance of a future pregnancy for three key groups of women:
those diagnosed with cancer who have not yet begun chemotherapy or radiotherapy;
those undergoing treatment with assisted reproductive technologies who do not consider embryo freezing an option; and
those who would like to preserve their future ability to have children, either because they do not yet have a partner, or for other personal or medical reasons.
Over 50,000 reproductive-age women are diagnosed with cancer each year in the United States. Chemotherapy and radiotherapy are toxic for oocytes, leaving few, if any, viable eggs. Egg-freezing offers women with cancer the chance to preserve their eggs, so that they can attempt to have children in the future.
Oocyte cryopreservation is an option for individuals undergoing IVF who object, either for religious or ethical reasons, to the practice of freezing embryos. In this way, there are no excess embryos created, and there need not be any disposal of unused frozen embryos.
Additionally, women with a family history of early menopause may have an interest in fertility preservation as to preserve viable eggs that could deteriorate at an earlier onset.
Method
The egg retrieval process for oocyte cryopreservation is the same as that for in vitro fertilization. This includes one to several weeks of hor |
https://en.wikipedia.org/wiki/Total%20human%20ecosystem | Total human ecosystem (THE) is an eco-centric concept initially proposed by ecology professors Zeev Naveh and Arthur S. Lieberman in 1994.
History of the concept
Naveh and Lieberman (1994) proposed the holistic, eco-centric concept of the Total Human Ecosystem in order to study the anthropocene ecology and improve land use planning and environmental management, within an integrated and interdisciplinary approach. In Naveh's own words, the Total Human Ecosystem is "the highest co-evolutionary ecological entity on earth with landscapes as its concrete three-dimensional ‘Gestalt’ systems, forming the spatial and functional matrix for all organisms". This concept (or meta-concept) integrates human systems (the technosphere, but also in the conceptual space of human noosphere) and natural systems (the geophysical eco-space of the Earth biosphere).
Zev Naveh (1919-2011), the major contributor to this concept, was Professor in landscape ecology at the Technion, Israel Institute of Technology, Haifa. Until 1965 he worked as a range and pasture specialist in Israel and Tanzania. His research at the Technion was devoted to human impacts on Mediterranean landscapes, fire ecology and dynamic conservation management, and the introduction of drought resistant plants for multi-beneficial landscape restoration and beautification.
Almo Farina, who also developed the concept from 2000 onwards, is also a professor of ecology at the Urbino University, Faculty of Environmental Sciences, in Italy.
Concepts and epistemology
The interaction and co-evolution of the human and natural ecosystem interactions are the driving forces for the current Earth system. The Total Human Ecosystem meta-conceptional approach aims to integrate the bio-and geo-centric approaches, derived from the natural sciences, and the approaches derived from the social sciences and the humanities in order to prevent further environmental degradation and drive natural and human systems towards a sustainable future.
|
https://en.wikipedia.org/wiki/Omphalotus%20nidiformis | Omphalotus nidiformis, or ghost fungus, is a gilled basidiomycete mushroom most notable for its bioluminescent properties. It is known to be found primarily in southern Australia and Tasmania, but was reported from India in 2012 and 2018. The fan or funnel shaped fruit bodies are up to across, with cream-coloured caps overlain with shades of orange, brown, purple, or bluish-black. The white or cream gills run down the length of the stipe, which is up to long and tapers in thickness to the base. The fungus is both saprotrophic and parasitic, and its fruit bodies are generally found growing in overlapping clusters on a wide variety of dead or dying trees.
First described scientifically in 1844, the fungus has been known by several names in its taxonomic history. It was assigned its current name by Orson K. Miller, Jr. in 1994. Its epithet name is derived from the Latin nidus "nest", hence 'nest shaped'. Similar in appearance to the common edible oyster mushroom, it was previously considered a member of the same genus, Pleurotus, and described under the former names Pleurotus nidiformis or Pleurotus lampas. Unlike oyster mushrooms, O. nidiformis is poisonous; while not lethal, its consumption leads to severe cramps and vomiting. The toxic properties of the mushroom are attributed to compounds called illudins. O. nidiformis is one of several species in the cosmopolitan genus Omphalotus, all of which have bioluminescent properties.
Taxonomy and naming
The ghost fungus was initially described in 1844 by English naturalist Miles Joseph Berkeley as Agaricus nidiformis. Berkeley felt it was related to Agaricus ostreatus (now Pleurotus ostreatus) but remarked it was a "far more magnificent species". Material was originally collected by Scottish naturalist James Drummond in 1841 on Banksia wood along the Swan River. He wrote "when this fungus was laid on a newspaper, it emitted by night a phosphorescent light, enabling us to read the words around it; and it continued to |
https://en.wikipedia.org/wiki/Baldwin%E2%80%93Lomax%20model | The Baldwin–Lomax model is a 0-equation turbulence model used in computational fluid dynamics analysis of turbulent boundary layer flows.
External links
Baldwin-Lomax model at cfd-online.com
Fluid dynamics
Mathematical modeling |
https://en.wikipedia.org/wiki/Cebeci%E2%80%93Smith%20model | The Cebeci–Smith model, developed by Tuncer Cebeci and Apollo M. O. Smith in 1967, is a 0-equation eddy viscosity model used in computational fluid dynamics analysis of turbulence in boundary layer flows. The model gives eddy viscosity, , as a function of the local boundary layer velocity profile. The model is suitable for high-speed flows with thin attached boundary layers, typically present in aerospace applications. Like the Baldwin-Lomax model, it is not suitable for large regions of flow separation and significant curvature or rotation. Unlike the Baldwin-Lomax model, this model requires the determination of a boundary layer edge.
Equations
In a two-layer model, the boundary layer is considered to comprise two layers: inner (close to the surface) and outer. The eddy viscosity is calculated separately for each layer and combined using:
where is the smallest distance from the surface where is equal to .
The inner-region eddy viscosity is given by:
where
with the von Karman constant usually being taken as 0.4, and with
The eddy viscosity in the outer region is given by:
where , is the displacement thickness, given by
and FK is the Klebanoff intermittency function given by |
https://en.wikipedia.org/wiki/Leukotriene%20D4 | Leukotriene D4 (LTD4) is one of the leukotrienes. Its main function in the body is to induce the contraction of smooth muscle, resulting in bronchoconstriction and vasoconstriction. It also increases vascular permeability. LTD4 is released by basophils. Other leukotrienes that function in a similar manner are leukotrienes C4 and E4. Pharmacological agents that inhibit the function of these leukotrienes are leukotriene receptor antagonists (e.g., zafirlukast, montelukast) and are useful for asthmatic individuals. |
https://en.wikipedia.org/wiki/Select%20%28Unix%29 | is a system call and application programming interface (API) in Unix-like and POSIX-compliant operating systems for examining the status of file descriptors of open input/output channels. The select system call is similar to the facility introduced in UNIX System V and later operating systems. However, with the c10k problem, both select and poll have been superseded by the likes of kqueue, epoll, /dev/poll and I/O completion ports.
One common use of select outside of its stated use of waiting on filehandles is to implement a portable sub-second sleep. This can be achieved by passing NULL for all three fd_set arguments, and the duration of the desired sleep as the timeout argument.
In the C programming language, the select system call is declared in the header file sys/select.h or unistd.h, and has the following syntax:
int select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *errorfds, struct timeval *timeout);
fd_set type arguments may be manipulated with four utility macros: , and .
Select returns the total number of bits set in and , or zero if the timeout expired, and -1 on error.
The sets of file descriptor used in select are finite in size, depending on the operating system. The newer system call provides a more flexible solution.
Example
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <sys/select.h>
#include <fcntl.h>
#include <unistd.h>
#include <err.h>
#include <errno.h>
#define PORT "9421"
/* function prototypes */
void die(const char*);
int main(int argc, char **argv)
{
int sockfd, new, maxfd, on = 1, nready, i;
struct addrinfo *res0, *res, hints;
char buffer[BUFSIZ];
fd_set master, readfds;
int error;
ssize_t nbytes;
(void)memset(&hints, '\0', sizeof(struct addrinfo));
hints.ai_family = AF_INET;
hints.ai_socktype = SOCK_STREAM;
hints.ai_protocol = IPPROTO_TCP;
hints.ai_fla |
https://en.wikipedia.org/wiki/Harry%20R.%20Lewis | Essentially all of Lewis's career has been at Harvard, where he has been honored for his "particularly distinguished contributions to undergraduate teaching"; his students have included future entrepreneurs Bill Gates and Mark Zuckerberg, and numerous future faculty members at Harvard and other schools.
The website "Six Degrees to Harry Lewis", created by Zuckerberg while at Harvard, was a precursor to Facebook.
Education and career
Lewis was born in Boston and grew up in Wellesley, . His parents were physicianshis father a hospital chief of anesthesiology and his mother the head of the Dever State School for disabled children. His father was a World War II veteran and the son of a German Lutheran father and a Russian Jewish mother. After graduating summa cum laude at the end of the eleventh grade at Boston's Roxbury Latin School he entered Harvard College, where he was for a time a third-string lacrosse goalie.
Lewis has said that he discovered "I wasn't a real [once] I got out of the amateur leagues of high school mathematics", but was "tremendously excited" by the computer-science research at Harvard.
As a senior he lectured a graduate class using a computer-graphics program, SHAPESHIFTER, which he had developed for displaying complex-plane on a cathode ray tube. SHAPESHIFTER automatically recognized formulas and commands hand-entered via a stylus on a RAND tablet, and could be "trained" to recognize the handwriting of individual users.
There being no degree program in computer science per se at Harvard at the time, in 1968 Lewis received his BA (summa, Quincy House) in applied mathematics and was elected to Phi Beta Kappa.
After serving for two years in the United States Public Health Service Commissioned Corps as a commissioned officer in the role of mathematician and computer scientist for the National Institutes of Health in Bethesda, Maryland,
he spent a year in Europe as a Frederick Sheldon Traveling Fellow.
He then returned to Harvard, where he ear |
https://en.wikipedia.org/wiki/Prostaglandin%20H2 | {{DISPLAYTITLE:Prostaglandin H2}}
Prostaglandin H2 is a type of prostaglandin and a precursor for many other biologically significant molecules. It is synthesized from arachidonic acid in a reaction catalyzed by a cyclooxygenase enzyme. The conversion from Arachidonic acid to Prostaglandin H2 is a two step process. First, COX-1 catalyzes the addition of two free oxygens to form the 1,2-Dioxane bridge and a peroxide functional group to form Prostaglandin G2. Second, COX-2 reduces the peroxide functional group to a Secondary alcohol, forming Prostaglandin H2. Other peroxidases like Hydroquinone have been observed to reduce PGG2 to PGH2. PGH2 is unstable at room temperature, with a half life of 90-100 seconds, so it is often converted into a different prostaglandin.
It is acted upon by:
Prostacyclin synthase to create prostacyclin
Thromboxane-A synthase to create thromboxane A2 and 12-(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) (see 12-Hydroxyheptadecatrienoic acid)
Prostaglandin D2 synthase to create prostaglandin D2
Prostaglandin E synthase to create prostaglandin E2
It rearranges non-enzymatically to:
A mixture of 12-(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) and 12-(S)-hydroxy-5Z,8Z,10E-heptadecatrienoic acid (see 12-Hydroxyheptadecatrienoic acid)
Use of prostaglandin H2:
regulating the constriction and dilation of blood vessels
stimulating platelet aggregation
binds to Thromboxane receptor on platelets' cell membranes to trigger platelet migration and adhesion to other platelets.
Effects of Aspirin on prostaglandin H2:
Aspirin has been hypothesized to block the conversion of arachidonic acid to prostaglandin |
https://en.wikipedia.org/wiki/Tempered%20representation | In mathematics, a tempered representation of a linear semisimple Lie group is a representation that has a basis whose matrix coefficients lie in the Lp space
L2+ε(G)
for any ε > 0.
Formulation
This condition, as just given, is slightly weaker than the condition that the matrix coefficients are square-integrable, in other words lie in
L2(G),
which would be the definition of a discrete series representation. If G is a linear semisimple Lie group with a maximal compact subgroup K, an admissible representation ρ of G is tempered if the above condition holds for the K-finite matrix coefficients of ρ.
The definition above is also used for more general groups, such as p-adic Lie groups and finite central extensions of semisimple real algebraic groups. The definition of "tempered representation" makes sense for arbitrary unimodular locally compact groups, but on groups with infinite centers such as infinite central extensions of semisimple Lie groups it does not behave well and is usually replaced by a slightly different definition. More precisely, an irreducible representation is called tempered if it is unitary when restricted to the center Z, and the absolute values of the matrix coefficients are in L2+ε(G/Z).
Tempered representations on semisimple Lie groups were first defined and studied by Harish-Chandra (using a different but equivalent definition), who showed that they are exactly the representations needed for the Plancherel theorem. They were classified by Knapp and Zuckerman, and used by Langlands in the Langlands classification of irreducible representations of a reductive Lie group G in terms of the tempered representations of smaller groups.
History
Irreducible tempered representations were identified by Harish-Chandra in his work on harmonic analysis on a semisimple Lie group as those representations that contribute to the Plancherel measure. The original definition of a tempered representation, which has certain technical advantages, is that it |
https://en.wikipedia.org/wiki/Prostaglandin%20E | Prostaglandin E is a family of naturally occurring prostaglandins that are used as medications.
Types include:
Prostaglandin E1 also known as alprostadil
Prostaglandin E2 also known as dinoprostone
Both types are on the World Health Organization's List of Essential Medicines.
Prostaglandin E play an important role in thermoregulation of the human brain. Decreased formation of prostaglandin E through inhibition of cyclooxygenase is the basis for the antipyretic of nonsteroidal anti-inflammatory drugs (NSAIDs). |
https://en.wikipedia.org/wiki/Arachidonic%20acid%205-hydroperoxide | Arachidonic acid 5-hydroperoxide (5-hydroperoxyeicosatetraenoic acid, 5-HPETE) is an intermediate in the metabolism of arachidonic acid by the ALOX5 enzyme in humans or Alox5 enzyme in other mammals. The intermediate is then further metabolized to: a) leukotriene A4 which is then metabolized to the chemotactic factor for leukocytes, leukotriene B4, or to contractors of lung airways, leukotriene C4, leukotriene D4, and leukotriene E4; b) the leukocyte chemotactic factors, 5-Hydroxyicosatetraenoic acid and 5-oxo-eicosatetraenoic acid; or c) the specialized pro-resolving mediators of inflammation, lipoxin A4 and lipoxin B4. |
https://en.wikipedia.org/wiki/Volva%20%28mycology%29 | In mycology, a volva is a cup-like structure at the base of a mushroom that is a remnant of the universal veil, or the remains of the peridium that encloses the immature fruit bodies of gasteroid fungi. This macrofeature is important in wild mushroom identification because it is an easily observed, taxonomically significant feature that frequently signifies a member of Amanitaceae. This has particular importance due to the disproportionately high number of deadly poisonous species contained within that family.
A mushroom's volva is often partially or completely buried in the ground, and therefore care must be taken to check for its presence when identifying mushrooms. Cutting or pulling mushrooms and attempting to identify them later without having noted this feature could be a fatal error.
Whilst a volva is a feature best known from Amanita species and stinkhorns such as the Phallaceae family and others in the Phallales order, it may also occur with other genera including:
Volvariella
Volvopluteus
Volvanarius
Battarrea
Some other species such as Leucoagaricus volvatus, Leucoagaricus bivelatus also display a volva despite this not being a typical trait for these genera.
In the Conocybe genus only six species out of the almost 300 described species are known to have a volva: C. anthuriae, C. corneri, C hornana, C. locellina, C. vaginata, C. volvata. |
https://en.wikipedia.org/wiki/Kravchuk%20polynomials | Kravchuk polynomials or Krawtchouk polynomials (also written using several other transliterations of the Ukrainian surname ) are discrete orthogonal polynomials associated with the binomial distribution, introduced by .
The first few polynomials are (for q = 2):
The Kravchuk polynomials are a special case of the Meixner polynomials of the first kind.
Definition
For any prime power q and positive integer n, define the Kravchuk polynomial
Properties
The Kravchuk polynomial has the following alternative expressions:
Symmetry relations
For integers , we have that
Orthogonality relations
For non-negative integers r, s,
Generating function
The generating series of Kravchuk polynomials is given as below. Here is a formal variable.
Three term recurrence
The Kravchuk polynomials satisfy the three-term recurrence relation
See also
Krawtchouk matrix
Hermite polynomials |
https://en.wikipedia.org/wiki/Udayana | Udayana, (Devanagari: उदयन) also known as Udayanācārya (Udyanacharya, or Master Udayana), (circa 975 - 1050 CE) was an Indian philosopher and logician of the tenth century of the Nyaya school who attempted to devise a rational theology to prove the existence of God using logic and counter the attack on the existence of God at the hands of Buddhist philosophers such as Dharmakīrti, Jñānaśrī and against the Indian school of materialism (Chārvaka). He is considered to be the most important philosopher of the Nyāya tradition.
He worked to reconcile the views held by the two major schools of logic (Nyaya and Vaisheshika). This became the root of the Navya-Nyāya ("New Nyāya") school of the thirteenth century, established by the Gangesha Upadhyaya school of "right" reasoning, which is still recognized and followed in some regions of India today. He lived in Kariyan village in Mithila, near present-day Darbhanga, Bihar state, India.
Udayana wrote a sub-gloss on Vachaspati Misra's work called the Nyaya-vaartika-taatparya-tiikaa-parishuddhi. He wrote several other works such as the Kusumanjali, Atma-tattva-viveka, Kiranaavali and Nyaya-parishishhta (also called Bodha siddhi or Bodha shuddhi).
He is given credit by Naiyāyikas for having demolished in a final fashion the claims of the Buddhist logicians. All his known works are thought to have been preserved, attesting to the importance given to him in Indian philosophy.
Early life
It is accepted by most scholars now that he was from Mithila, Bihar. Scholars are almost unanimous in declaring Udayana to be one of the greatest of Indian philosophers. In the Nyāya-Vaiśeṣika school itself, to which he belongs, he occupies a singular position of authority and renown. Flourishing at the period of transition from the Older Nyāya to the New (Navya-Nyāya), he shines as an unrivalled master of the former and an inspiring herald of the latter. For example, Gaṇgeśa Upādhyāya, the 14th century Indian philosopher and mathematician who e |
https://en.wikipedia.org/wiki/I/O%20request%20packet | I/O request packets (IRPs) are kernel mode structures that are used by Windows Driver Model (WDM) and Windows NT device drivers to communicate with each other and with the operating system. They are data structures that describe I/O requests, and can be equally well thought of as "I/O request descriptors" or similar. Rather than passing a large number of small arguments (such as buffer address, buffer size, I/O function type, etc.) to a driver, all of these parameters are passed via a single pointer to this persistent data structure. The IRP with all of its parameters can be put on a queue if the I/O request cannot be performed immediately. I/O completion is reported back to the I/O manager by passing its address to a routine for that purpose, IoCompleteRequest. The IRP may be repurposed as a special kernel APC object if such is required to report completion of the I/O to the requesting thread.
IRPs are typically created by the I/O Manager in response to I/O requests from user mode. However, IRPs are sometimes created by the plug-and-play manager, power manager, and other system components, and can also be created by drivers and then passed to other drivers.
The I/O request packet mechanism is also used by Digital Equipment Corporation's VMS operating system, and was used by Digital's RSX-11 family of operating systems before that. An I/O request packet in RSX-11 is called a directive parameter block, as it is also used for system calls other than I/O calls.
See also
Architecture of Windows NT |
https://en.wikipedia.org/wiki/Natural%20wine | Natural wine (; ) refers to a generalized movement among winemakers for production of wine using simple or traditional methods. Although there is no uniform definition of natural wine, it is usually produced without the use of pesticides or herbicides and with few or no additives. Typically, natural wine is produced on a small scale using traditional rather than industrial techniques and fermented with native yeast. In its purest form, natural wine is simply unadulterated fermented grape juice with no additives in the winemaking process. Other terms for the product include low-intervention wine, raw wine, and naked wine.
History
Some sources claim that the movement started with winemakers in the Beaujolais region of France in the 1960s. Several winemakers, namely Marcel Lapierre, Jean Foillard, Charly Thevenet, and Guy Breton, sought a return to the way their grandparents made wine, before the incursion of pesticides and synthetic chemicals that had become so prevalent in agriculture after the end of World War II. They became affectionately known as The Gang of Four. They were heavily influenced by the teachings and thoughts of Jules Chauvet and Jacques Neauport, two oenologists who studied ways to make wines with fewer additives. For quite some time the town of Villié-Morgon became a place for like minded winemakers to congregate and become influenced by the Gang of Four. Gradually this movement spread to other regions of France, and since has spread across the world, gradually gaining in popularity and attracting newer younger winemakers in more and more regions of the world.
Historically, natural wine has been connected to the German Lebensreform movement, where it gained popularity in the late 19th and early 20th centuries.
In the end of 19th century prominent Georgian poet and politician, Ilia Chavchavadze penned a series of articles responding to contemporary critics of “backward” natural winemaking practices, later collected and published under the title “ |
https://en.wikipedia.org/wiki/Process%20performance%20index | In process improvement efforts, the process performance index is an estimate of the process capability of a process during its initial set-up, before it has been brought into a state of statistical control.
Formally, if the upper and lower specifications of the process are USL and LSL, the estimated mean of the process is , and the estimated variability of the process (expressed as a standard deviation) is , then the process performance index is defined as:
is estimated using the sample standard deviation. Ppk may be negative if the process mean falls outside the specification limits (because the process is producing a large proportion of defective output).
Some specifications may only be one sided (for example, strength). For specifications that only have a lower limit, ; for those that only have an upper limit, .
Practitioners may also encounter , a metric that does not account for process performance not exactly centered between the specification limits, and therefore is interpreted as what the process would be capable of achieving if it could be centered and stabilized.
Interpretation
Larger values of Ppk may be interpreted to indicate that a process is more capable of producing output within the specification limits, though this interpretation is controversial. Strictly speaking, from a statistical standpoint, Ppk is meaningless if the process under study is not in control because one cannot reliably estimate the process underlying probability distribution, let alone parameters like and . Furthermore, using this metric of past process performance to predict future performance is highly suspect.
From a management standpoint, when an organization is under pressure to set up a new process quickly and economically, Ppk is a convenient metric to gauge how set-up is progressing (increasing Ppk being interpreted as "the process capability is improving"). The risk is that Ppk is taken to mean a process is ready for production before all the kinks have been |
https://en.wikipedia.org/wiki/Triangular%20routing | Triangular routing is a method for transmitting packets of data in communications networks. It uses a form of routing that sends a packet to a proxy system before transmission to the intended destination. Triangular routing is a problem in mobile IP; however, it finds applications in other networking situations, for instance to avoid problems associated with network address translation (NAT), implemented for example by Skype.
2) Datagram is intercepted 3) Datagram is
by home agent and detunneled and
is tunneled to the delivered to the
care-of address. mobile node.
+-----+ +-------+ +------+
|home | =======> |foreign| ------> |mobile|
|agent| | agent | <------ | node |
+-----+ +-------+ +------+
1) Datagram to /|\ /
mobile node | / 4) For datagrams sent by the
arrives on | / mobile node, standard IP
home network | / routing delivers each to its
via standard | |_ destination. In this figure,
IP routing. +----+ the foreign agent is the
|host| mobile node's default router.
+----+
Figure 1: Operation of Mobile IPv4
Description
Notations Used
CH - Correspondent Host
MH - Mobile Host
HA - Home Agent
FA - Foreign Agent
Triangular Routing Problem
The problem in communication between a fixed host and a mobile host, such as a home computer and a smartphone, is that while the mobile host knows the fixed host's address, the fixed host does not know the mobile host's current address. Therefore, different routing must be used for the different directions.
In mobile IP, packets that are sent to a mobile host by the correspondent host are first routed to the |
https://en.wikipedia.org/wiki/Mean%20shift | Mean shift is a non-parametric feature-space mathematical analysis technique for locating the maxima of a density function, a so-called mode-seeking algorithm. Application domains include cluster analysis in computer vision and image processing.
History
The mean shift procedure is usually credited to work by Fukunaga and Hostetler in 1975. It is, however, reminiscent of earlier work by Schnell in 1964.
Overview
Mean shift is a procedure for locating the maxima—the modes—of a density function given discrete data sampled from that function. This is an iterative method, and we start with an initial estimate . Let a kernel function be given. This function determines the weight of nearby points for re-estimation of the mean. Typically a Gaussian kernel on the distance to the current estimate is used, . The weighted mean of the density in the window determined by is
where is the neighborhood of , a set of points for which .
The difference is called mean shift in Fukunaga and Hostetler.
The mean-shift algorithm now sets , and repeats the estimation until converges.
Although the mean shift algorithm has been widely used in many applications, a rigid proof for the convergence of the algorithm using a general kernel in a high dimensional space is still not known. Aliyari Ghassabeh showed the convergence of the mean shift algorithm in one dimension with a differentiable, convex, and strictly decreasing profile function. However, the one-dimensional case has limited real world applications. Also, the convergence of the algorithm in higher dimensions with a finite number of the stationary (or isolated) points has been proved. However, sufficient conditions for a general kernel function to have finite stationary (or isolated) points have not been provided.
Gaussian Mean-Shift is an Expectation–maximization algorithm.
Details
Let data be a finite set embedded in the -dimensional Euclidean space, . Let be a flat kernel that is the characteristic function of th |
https://en.wikipedia.org/wiki/Millimeter%20Anisotropy%20eXperiment%20IMaging%20Array | The Millimeter Anisotropy eXperiment IMaging Array (MAXIMA) experiment was a balloon-borne experiment funded by the United States NSF, NASA, and Department of Energy, and operated by an international collaboration headed by the University of California, to measure the fluctuations of the cosmic microwave background. It consisted of two flights, one in August 1998 and one in June 1999. For each flight the balloon was started at the Columbia Scientific Balloon Facility in Palestine, Texas and flew to an altitude of 40,000 metres for over 8 hours. For the first flight it took data from about 0.3 percent of the sky of the northern region near the Draco constellation. For the second flight, known as MAXIMA-II, twice the area was observed, this time in the direction of Ursa Major.
Initially planned together with the BOOMERanG experiment, it split off during the planning phase to take a less risky approach by reducing flying time as well as launching and landing on U.S. territory.
Instrumentation
A 1.3-metre primary mirror, along with a smaller secondary and tertiary mirror, was used to focus the microwaves onto the feed horns. The feed horns had spectral bands centred at 150, 240 and 420 GHz with a resolution of 10 arcminutes. A bolometer array consisting of sixteen NTD-Ge thermistors measured the incident radiation.
The detector array was cooled to 100 mK via a four-stage refrigeration process. Liquid nitrogen cooled the outer layer of radiation shielding and He-4 was used to cool the two other layers to a temperature of 2-3 K. Finally liquid He-3 cooled the array down to operation temperature. The shielding, together with the properties of the feed horns, gave a sensitivity of .
Two CCD cameras were used to provide accurate measurements of the telescope's orientation. The first wide-field camera pointed towards Polaris and gave a coarse orientation up to 15 arcminutes. The other camera was mounted in the primary focus and gave an accuracy of half an arcminute for |
https://en.wikipedia.org/wiki/Homomorphic%20secret%20sharing | In cryptography, homomorphic secret sharing is a type of secret sharing algorithm in which the secret is encrypted via homomorphic encryption. A homomorphism is a transformation from one algebraic structure into another of the same type so that the structure is preserved. Importantly, this means that for every kind of manipulation of the original data, there is a corresponding manipulation of the transformed data.
Technique
Homomorphic secret sharing is used to transmit a secret to several recipients as follows:
Transform the "secret" using a homomorphism. This often puts the secret into a form which is easy to manipulate or store. In particular, there may be a natural way to 'split' the new form as required by step (2).
Split the transformed secret into several parts, one for each recipient. The secret must be split in such a way that it can only be recovered when all or most of the parts are combined. (See Secret sharing.)
Distribute the parts of the secret to each of the recipients.
Combine each of the recipients' parts to recover the transformed secret, perhaps at a specified time.
Reverse the homomorphism to recover the original secret.
Examples
Suppose a community wants to perform an election, using a decentralized voting protocol, but they want to ensure that the vote-counters won't lie about the results. Using a type of homomorphic secret sharing known as Shamir's secret sharing, each member of the community can add their vote to a form that is split into pieces, each piece is then submitted to a different vote-counter. The pieces are designed so that the vote-counters can't predict how any alterations to each piece will affect the whole, thus, discouraging vote-counters from tampering with their pieces. When all votes have been received, the vote-counters combine them, allowing them to recover the aggregate election results.
In detail, suppose we have an election with:
Two possible outcomes, either yes or no. We'll represent those outcomes nume |
https://en.wikipedia.org/wiki/Phylogenetic%20bracketing | Phylogenetic bracketing is a method of inference used in biological sciences. It is used to infer the likelihood of unknown traits in organisms based on their position in a phylogenetic tree. One of the main applications of phylogenetic bracketing is on extinct organisms, known only from fossils, going all the way back to the last universal common ancestor (LUCA). The method is often used for understanding traits that do not fossilize well, such as soft tissue anatomy, physiology and behaviour. By considering the closest and second-closest well-known (usually extant) organisms, traits can be asserted with a fair degree of certainty, though the method is extremely sensitive to problems from convergent evolution.
Method
Extant Phylogenetic Bracketing requires that the species forming the brackets be extant. More general forms of phylogenetic bracketing do not require this and may use a mix of extant and extinct taxa to form the bracket. These more generalized forms of phylogenetic bracketing have the advantage in that they can be applied to a wider array of phylogenetic cases. However, since these forms of bracketing are also more generalized and may rely on inferring traits in extinct animals, they also offer lower explanatory power compared to the EPB.
Extant phylogenetic bracketing (EPB)
This is a popular form of phylogenetic bracketing first introduced by Witmer in 1995. It works by comparing an extinct taxon to its nearest living relatives. For example, Tyrannosaurus, a theropod dinosaur, is bracketed by birds and crocodiles. A feature found in both birds and crocodiles would likely be present in Tyrannosaurus, such as the capability to lay an amniotic egg, whereas a feature both birds and crocodiles lack, such as hair, would probably not be present in Tyrannosaurus. Sometimes this approach is used for the reconstruction of ecological traits as well.
Levels of inference
The extant phylogenetic bracket approach allows researchers to infer traits in extinct a |
https://en.wikipedia.org/wiki/TIME-ITEM | TIME-ITEM is an ontology of Topics that describes the content of undergraduate medical education. TIME is an acronym for "Topics for Indexing Medical Education"; ITEM is an acronym for "Index de thèmes pour l’éducation médicale." Version 1.0 of the taxonomy has been released and the web application that allows users to work with it is still under development. Its developers are seeking more collaborators to expand and validate the taxonomy and to guide future development of the web application.
History
The development of TIME-ITEM began at the University of Ottawa in 2006. It was initially developed to act as a content index for a curriculum map being constructed there. After its initial presentation at the 2006 conference of the Canadian Association for Medical Education, early collaborators included the University of British Columbia, McMaster University and Queen's University.
Features
The TIME-ITEM ontology is unique in that it is designed specifically for undergraduate medical education. As such, it includes fewer strictly biomedical entries than other common medical vocabularies (such as MeSH or SNOMED CT) but more entries relating to the medico-social concepts of communication, collaboration, professionalism, etc.
Topics within TIME-ITEM are arranged poly-hierarchically, meaning any Topic can have more than one parent. Relationships are established based on the logic that learning about a Topic contributes to the learning of all its parent Topics.
In addition to housing the ontology of Topics, the TIME-ITEM web application can house multiple Outcome frameworks. All Outcomes, whether private Outcomes entered by single institutions or publicly available medical education Outcomes (such as CanMeds 2005) are hierarchically linked to one or more Topics in the ontology. In this way, the contribution of each Topic to multiple Outcomes is made explicit.
The structure of the XML documents exported from TIME-ITEM (which contain the hierarchy of Outco |
https://en.wikipedia.org/wiki/Penetrating%20trauma | Penetrating trauma is an open wound injury that occurs when an object pierces the skin and enters a tissue of the body, creating a deep but relatively narrow entry wound. In contrast, a blunt or non-penetrating trauma may have some deep damage, but the overlying skin is not necessarily broken and the wound is still closed to the outside environment. The penetrating object may remain in the tissues, come back out the path it entered, or pass through the full thickness of the tissues and exit from another area.
A penetrating injury in which an object enters the body or a structure and passes all the way through an exit wound is called a perforating trauma, while the term penetrating trauma implies that the object does not perforate wholly through. In gunshot wounds, perforating trauma is associated with an entrance wound and an often larger exit wound.
Penetrating trauma can be caused by a foreign object or by fragments of a broken bone. Usually occurring in violent crime or armed combat, penetrating injuries are commonly caused by gunshots and stabbings.
Penetrating trauma can be serious because it can damage internal organs and presents a risk of shock and infection. The severity of the injury varies widely depending on the body parts involved, the characteristics of the penetrating object, and the amount of energy transmitted to the tissues. Assessment may involve X-rays or CT scans, and treatment may involve surgery, for example to repair damaged structures or to remove foreign objects. Following penetrating trauma, spinal motion restriction is associated with worse outcomes and therefore it should not be done routinely.
Mechanism
As a missile passes through tissue, it decelerates, dissipating and transferring kinetic energy to the tissues. The velocity of the projectile is a more important factor than its mass in determining how much damage is done; kinetic energy increases with the square of the velocity. In addition to injury caused directly by the |
https://en.wikipedia.org/wiki/Strong%20partition%20cardinal | In Zermelo–Fraenkel set theory without the axiom of choice a strong partition cardinal is an uncountable well-ordered cardinal such that every partition of the set of size subsets of into less than pieces has a homogeneous set of size .
The existence of strong partition cardinals contradicts the axiom of choice. The Axiom of determinacy implies that ℵ1 is a strong partition cardinal. |
https://en.wikipedia.org/wiki/Camptodactyly | Camptodactyly is a medical condition that causes one or more fingers or toes to be permanently bent. It involves fixed flexion deformity of the proximal interphalangeal joints.
Camptodactyly can be caused by a genetic disorder. In that case, it is an autosomal dominant trait that is known for its incomplete genetic expressivity. This means that when a person has the genes for it, the condition may appear in both hands, one, or neither. A linkage scan proposed that the chromosomal locus of camptodactyly was 3q11.2-q13.12.
Causes
The specific cause of camptodactyly remains unknown, but there are a few deficiencies that lead to the condition. A deficient lumbrical muscle controlling the flexion of the fingers, and abnormalities of the flexor and extensor tendons.
A number of congenital syndromes may also cause camptodactyly:
Jacobsen syndrome
Beals syndrome
Blau syndrome
Freeman–Sheldon syndrome
Cerebrohepatorenal syndrome
Weaver syndrome
Christian syndrome 1
Gordon syndrome
Jacobs arthropathy-camptodactyly syndrome
Lenz microphthalmia syndrome
Marshall–Smith–Weaver syndrome
Oculo-dento-digital syndrome
Tel Hashomer camptodactyly syndrome
Toriello–Carey syndrome
Trisomy 13
Stuve–Wiedemann syndrome
Loeys–Dietz syndrome
Fetal alcohol syndrome
Fryns syndrome
Marfan syndrome
Carnio-carpo-tarsal dystrophy
Genetics
The pattern of inheritance is determined by the phenotypic expression of a gene—which is called expressivity. Camptodactyly can be passed on through generations in various levels of phenotypic expression, which include both or only one hand. This means that the genetic expressivity is incomplete. It can be inherited from either parent.
In most of its cases, camptodactyly occurs sporadically, but it has been found in several studies that it is inherited as an autosomal dominant condition.
Treatment
If a contracture is less than 30 degrees, it may not interfere with normal functioning. The common treatment is splinting and occupation |
https://en.wikipedia.org/wiki/Reverse%20connection | A reverse connection is usually used to bypass firewall restrictions on open ports. A firewall usually blocks incoming connections on open ports,
but does not block outgoing traffic. In a normal forward connection, a client connects to a server through the server's open port,
but in the case of a reverse connection, the client opens the port that the server connects to.
The most common way a reverse connection is used is to bypass firewall and router security restrictions.
For example, a backdoor running on a computer behind a firewall that blocks incoming connections can easily open an outbound connection to a remote host on the Internet. Once the connection is established, the remote host can send commands to the backdoor.
Remote administration tools (RAT) that use a reverse connection usually send SYN packets to the client's IP address.
The client listens for these SYN packets and accepts the desired connections.
If a computer is sending SYN packets or is connected to the client's computer, the connections can be discovered by using the netstat command or a common port listener like “Active Ports”.
If the Internet connection is closed down and an application still tries to connect to remote hosts it may be infected with malware.
Keyloggers and other malicious programs are harder to detect once installed, because they connect only once per session. Note that SYN packets by themselves are not necessarily a cause for alarm, as they are a standard part of all TCP connections.
There are honest uses for using reverse connections, for example to allow hosts behind a NAT firewall to be administered remotely. These hosts do not normally have public IP addresses, and so must either have ports forwarded at the firewall, or open reverse connections to a central administration server. |
https://en.wikipedia.org/wiki/Halo%20orbit | A halo orbit is a periodic, three-dimensional orbit near one of the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is that it can be orbited by a Lissajous orbit or by a halo orbit. These can be thought of as resulting from an interaction between the gravitational pull of the two planetary bodies and the Coriolis and centrifugal force on a spacecraft. Halo orbits exist in any three-body system, e.g., a Sun–Earth–orbiting satellite system or an Earth–Moon–orbiting satellite system. Continuous "families" of both northern and southern halo orbits exist at each Lagrange point. Because halo orbits tend to be unstable, station-keeping using thrusters may be required to keep a satellite on the orbit.
Most satellites in halo orbit serve scientific purposes, for example space telescopes.
Definition and history
Robert W. Farquhar first used the name "halo" in 1966 for orbits around L which were made periodic using thrusters. Farquhar advocated using spacecraft in such an orbit beyond the Moon (Earth–Moon ) as a communications relay station for an Apollo mission to the far side of the Moon. A spacecraft in such an orbit would be in continuous view of both the Earth and the far side of the Moon, whereas a Lissajous orbit would sometimes make the spacecraft go behind the Moon. In the end, no relay satellite was launched for Apollo, since all landings were on the near side of the Moon.
In 1973 Farquhar and Ahmed Kamel found that when the in-plane amplitude of a Lissajous orbit was large enough there would be a corresponding out-of-plane amplitude that would have the same period, so the orbit ceased to be a Lissajous orbit and became approximately an ellipse. They used analytical expressions to represent these halo orbits; in 1984, Kathleen Howell showed that more precise trajectories could be computed numerically. Additionally, she found that for most values of t |
https://en.wikipedia.org/wiki/PRMT4%20pathway | Protein arginine N-methyltransferase-4 (PRMT4/CARM1) methylation of arginine residues within proteins plays a critical key role in transcriptional regulation (see the PRMT4 pathway on the left). PRMT4 binds to the classes of transcriptional activators known as p160 and CBP/p300. The modified forms of these proteins are involved in stimulation of gene expression via steroid hormone receptors. Significantly, PRMT4 methylates core histones H3 and H4, which are also targets of the histone acetylase activity of CBP/p300 coactivators. PRMT4 recruitment of chromatin by binding to coactivators increases histone methylation and enhances the accessibility of promoter regions for transcription. Methylation of the transcriptional coactivator CBP by PRMT4 inhibits binding to CREB and thereby partitions the limited cellular pool of CBP for steroid hormone receptor interaction.
See also
DNA methyltransferase
Nucleosome
Histone
Histone-Modifying Enzymes
Chromatin
Diet and cancer |
https://en.wikipedia.org/wiki/Email%20encryption | Email encryption is encryption of email messages to protect the content from being read by entities other than the intended recipients. Email encryption may also include authentication.
Email is prone to the disclosure of information. Most emails are encrypted during transmission, but they are stored in clear text, making them readable by third parties such as email providers. By default, popular email services such as Gmail and Outlook do not enable end-to-end encryption. By means of some available tools, persons other than the designated recipients can read the email contents.
Email encryption can rely on public-key cryptography, in which users can each publish a public key that others can use to encrypt messages to them, while keeping secret a private key they can use to decrypt such messages or to digitally encrypt and sign messages they send.
Encryption protocols
With the original design of email protocol, the communication between email servers was in plain text, which posed a huge security risk. Over the years, various mechanisms have been proposed to encrypt the communication between email servers. Encryption may occur at the transport level (aka "hop by hop") or end-to-end. Transport layer encryption is often easier to set up and use; end-to-end encryption provides stronger defenses, but can be more difficult to set up and use.
Transport-level encryption
One of the most commonly used email encryption extensions is STARTTLS. It is a TLS (SSL) layer over the plaintext communication, allowing email servers to upgrade their plaintext communication to encrypted communication. Assuming that the email servers on both the sender and the recipient side support encrypted communication, an eavesdropper snooping on the communication between the mail servers cannot use a sniffer to see the email contents. Similar STARTTLS extensions exist for the communication between an email client and the email server (see IMAP4 and POP3, as stated by RFC 2595). STARTTLS may be |
https://en.wikipedia.org/wiki/Evolutionary%20history%20of%20plants | The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved through endosymbiosis, through multicellular marine and freshwater green algae, to spore-bearing terrestrial bryophytes, lycopods and ferns, and eventually to the complex seed-bearing gymnosperms and angiosperms (flowering plants) of today. While many of the earliest groups continue to thrive, as exemplified by red and green algae in marine environments, more recently derived groups have displaced previously ecologically dominant ones; for example, the ascendance of flowering plants over gymnosperms in terrestrial environments.
There is evidence that cyanobacteria and multicellular photosynthetic eukaryotes lived in freshwater communities on land as early as 1 billion years ago, and that communities of complex, multicellular photosynthesizing organisms existed on land in the late Precambrian, around .
Evidence of the emergence of embryophyte land plants first occurs in the mid-Ordovician (~), and by the middle of the Devonian (~), many of the features recognised in land plants today were present, including roots and leaves. By the late Devonian (~) some free-sporing plants such as Archaeopteris had secondary vascular tissue that produced wood and had formed forests of tall trees. Also by the late Devonian, Elkinsia, an early seed fern, had evolved seeds.
Evolutionary innovation continued throughout the rest of the Phanerozoic eon and still continues today. Most plant groups were relatively unscathed by the Permo-Triassic extinction event, although the structures of communities changed. This may have set the scene for the appearance of the flowering plants in the Triassic (~), and their later diversification in the Cretaceous and Paleogene. The latest major group of plants to evolve were the grasses, which became important in the mid-Paleogene, from around . The grasses, as well as many other groups, evolved new mechanisms of metab |
https://en.wikipedia.org/wiki/Uridine%20diphosphate%20glucuronic%20acid | UDP-glucuronic acid is a sugar used in the creation of polysaccharides and is an intermediate in the biosynthesis of ascorbic acid (except in primates and guinea pigs). It also participates in the heme degradation process of human.
It is made from UDP-glucose by UDP-glucose 6-dehydrogenase (EC 1.1.1.22) using NAD+ as a cofactor. It is the source of the glucuronosyl group in glucuronosyltransferase reactions.
See also
Glucuronic acid
UDP |
https://en.wikipedia.org/wiki/Uridine%20diphosphate%20galactose | Uridine diphosphate galactose (UDP-galactose) is an intermediate in the production of polysaccharides. It is important in nucleotide sugars metabolism, and is the substrate for the transferase B4GALT5.
See also
Galactose
UDP galactose epimerase
Uridine diphosphate |
https://en.wikipedia.org/wiki/Realizability | In mathematical logic, realizability is a collection of methods in proof theory used to study constructive proofs and extract additional information from them. Formulas from a formal theory are "realized" by objects, known as "realizers", in a way that knowledge of the realizer gives knowledge about the truth of the formula. There are many variations of realizability; exactly which class of formulas is studied and which objects are realizers differ from one variation to another.
Realizability can be seen as a formalization of the BHK interpretation of intuitionistic logic; in realizability the notion of "proof" (which is left undefined in the BHK interpretation) is replaced with a formal notion of "realizer". Most variants of realizability begin with a theorem that any statement that is provable in the formal system being studied is realizable. The realizer, however, usually gives more information about the formula than a formal proof would directly provide.
Beyond giving insight into intuitionistic provability, realizability can be applied to prove the disjunction and existence properties for intuitionistic theories and to extract programs from proofs, as in proof mining. It is also related to topos theory via realizability topoi.
Example: Kleene's 1945-realizability
Kleene's original version of realizability uses natural numbers as realizers for formulas in Heyting arithmetic. A few pieces of notation are required: first, an ordered pair (n,m) is treated as a single number using a fixed primitive recursive pairing function; second, for each natural number n, φn is the computable function with index n. The following clauses are used to define a relation "n realizes A" between natural numbers n and formulas A in the language of Heyting arithmetic, known as Kleene's 1945-realizability relation:
Any number n realizes an atomic formula s=t if and only if s=t is true. Thus every number realizes a true equation, and no number realizes a false equation.
A pair (n,m |
https://en.wikipedia.org/wiki/Phallolysin | Phallolysin is a protein found the Amanita phalloides species of the Amanita genus of mushrooms, the species commonly known as the death cap mushroom. The protein is toxic and causes cytolysis in many cells found in animals and is noted for its hemolytic properties. It was one of the first toxins discovered in Amanita phalloides when the various toxins in the species where first being researched. The protein itself is observed to come in 3 variations, with observed differences in isoelectric point.
History
The toxic properties of death cap mushrooms have been known for most of recorded history, with historical accounts implicating it in the deaths of emperors. Attempts to isolate the toxic compounds began in the late 19th century, with the cytolytic elements of A. phalloides being isolated in 1891.
Physical properties
Phallolysin has three variations, which differ in observed isoelectric point. The variations have differences in the amino acids that make up the protein structure, with identical amounts of some amino acids while varying in others. They have near identical molecular weights of 34 kDa.
Effects on animal cells
Phallolysin has been observed to have hemolytic properties toward a variety of animal cells, with it primarily being observed in mammals. The toxic effects are reduced at higher temperatures.
See also
Amanita phalloides
Amanita
Hemolysis
Phallotoxin
Amatoxin
Virotoxins
Phalloidin
Antamanide |
https://en.wikipedia.org/wiki/Stephen%20J.%20Mellor | Stephen J. Mellor (born 1952) is an American computer scientist, developer of the Ward–Mellor method for real-time computing, the Shlaer–Mellor method, and Executable UML, and signatory to the Agile Manifesto.
Biography
Mellor received a BA in computer science from the University of Essex in 1974, and started working at CERN in Geneva, Switzerland as a programmer in BCPL. In 1977 he became software engineer at the Lawrence Berkeley Laboratory, and in 1982 consultant at Yourdon, Inc.
At Yourdon in cooperation with Paul Ward they developed the Ward–Mellor method, and published the book-series Structured Development for Real Time Systems in 1985.
Together with Sally Shlaer he founded Project Technology in 1985. That company was acquired by Mentor Graphics in 2004. Mellor stayed as chief scientist of the Embedded Systems Division at Mentor Graphics for another two years, and is self-employed since 2006.
Since 1998 Mellor has contributed to the Object Management Group, chairing the consortium that added executable actions to the UML, and the specification of model-driven architecture (MDA). He is also chairing the advisory board of the IEEE Software magazine. Since 2013, Mellor has served as CTO for the Industrial Internet Consortium.
Publications
1985. Structured Development for Real-Time Systems: Essential Modeling Techniques. With Paul T. Ward. Prentice Hall.
1986. Structured Development for Real-Time Systems: Implementation Modeling Techniques (Structured Development for Real-Time Systems Vol. 1). With Paul T. Ward. Prentice Hall.
1988. Object Oriented Systems Analysis: Modeling the World in Data. With Sally Shlaer. Prentice Hall.
1992. Object Life Cycles: Modeling the World In States. With Sally Shlaer. Prentice Hall.
2002. Executable UML: A Foundation for Model Driven Architecture. With Marc J. Balcer. Addison-Wesley.
2004. MDA Distilled. With Kendall Scott, Axel Uhl, Dirk Weise. Addison-Wesley.
Articles, a selection:
1989. "An object-oriented appro |
https://en.wikipedia.org/wiki/Bioenergetic%20systems | Bioenergetic systems are metabolic processes that relate to the flow of energy in living organisms. Those processes convert energy into adenosine triphosphate (ATP), which is the form suitable for muscular activity. There are two main forms of synthesis of ATP: aerobic, which uses oxygen from the bloodstream, and anaerobic, which does not. Bioenergetics is the field of biology that studies bioenergetic systems.
Overview
The process that converts the chemical energy of food into ATP (which can release energy) is not dependent on oxygen availability. During exercise, the supply and demand of oxygen available to muscle cells is affected by duration and intensity and by the individual's cardio respiratory fitness level. It is also affected by the type of activity, for instance, during isometric activity the contracted muscles restricts blood flow (leaving oxygen and blood borne fuels unable to be delivered to muscle cells adequately for oxidative phosphorylation). Three systems can be selectively recruited, depending on the amount of oxygen available, as part of the cellular respiration process to generate ATP for the muscles. They are ATP, the anaerobic system and the aerobic system.
Adenosine triphosphate
ATP is the only type of usable form of chemical energy for musculoskeletal activity. It is stored in most cells, particularly in muscle cells. Other forms of chemical energy, such as those available from oxygen and food, must be transformed into ATP before they can be utilized by the muscle cells.
Coupled reactions
Since energy is released when ATP is broken down, energy is required to rebuild or resynthesize it. The building blocks of ATP synthesis are the by-products of its breakdown; adenosine diphosphate (ADP) and inorganic phosphate (Pi). The energy for ATP resynthesis comes from three different series of chemical reactions that take place within the body. Two of the three depend upon the food eaten, whereas the other depends upon a chemical compound called p |
https://en.wikipedia.org/wiki/Face-ism | Face-ism or facial prominence is the relative proportion of the face compared to the body in the portrayal of men and women. The media tends to give higher proportion to men's faces and women's bodies.
Origin and evidence
The term "face-ism" or "facial prominence" was initially defined in a 1983 study in which facial prominence was measured by a "Face-ism index", which is the ratio of two linear measurements, with the distance (in millimeters or any other unit) from the top of the head to the lowest visible point of the chin being the numerator and the distance from the top of the head to the lowest visible part of the subject's body the denominator. It was found that across societies and time, facial prominence of men has been much higher than that of women.
Subsequent studies have generated consistent findings and thus helped confirm the pervasive presence of face-ism. For instance, a prevalent face-ism phenomenon was observed in news magazines and women's magazines of the 1970s and 1980s. Face-ism has been documented in prime-time television programs. Evidence has been shown that face-ism is still present in mainstream printed media from as recently as 2004, and showed that men in intellectually focused occupations tend to have higher face-to-body ratios than women in similar professions, while women in physical occupations tend to have higher face-to-body ratios than men in similar professions. A cross-cultural study on face-ism found that face-ism in photographs of politicians is more pronounced in gender-egalitarian societies compared to gender-unequal societies.
There is no relation between face-ism and the perception of intellect.
Implications
It was found that regardless of gender difference, news photographs featuring high face prominence tend to generate more positive ratings with regard to intelligence, ambition and physical appearance than those with low face prominence.
Similarly, another study argued that as a series of mental life dimensions i |
https://en.wikipedia.org/wiki/Hausdorff%20density | In measure theory, a field of mathematics, the Hausdorff density measures how concentrated a Radon measure is at some point.
Definition
Let be a Radon measure and some point in Euclidean space. The s-dimensional upper and lower Hausdorff densities are defined to be, respectively,
and
where is the ball of radius r > 0 centered at a. Clearly, for all . In the event that the two are equal, we call their common value the s-density of at a and denote it .
Marstrand's theorem
The following theorem states that the times when the s-density exists are rather seldom.
Marstrand's theorem: Let be a Radon measure on . Suppose that the s-density exists and is positive and finite for a in a set of positive measure. Then s is an integer.
Preiss' theorem
In 1987 David Preiss proved a stronger version of Marstrand's theorem. One consequence is that sets with positive and finite density are rectifiable sets.
Preiss' theorem: Let be a Radon measure on . Suppose that m is an integer and the m-density exists and is positive and finite for almost every a in the support of . Then is m-rectifiable, i.e. ( is absolutely continuous with respect to Hausdorff measure ) and the support of is an m-rectifiable set.
External links
Density of a set at Encyclopedia of Mathematics
Rectifiable set at Encyclopedia of Mathematics |
https://en.wikipedia.org/wiki/Foie%20gras%20controversy | The production of foie gras (the liver of a duck or a goose that has been specially fattened) involves the controversial force-feeding of birds with more food than they would eat in the wild, and more than they would voluntarily eat domestically. The feed, usually corn boiled with fat (to facilitate ingestion), deposits large amounts of fat in the liver, thereby producing the fatty consistency sought by some gastronomes.
Animal rights and welfare groups
Animal rights and welfare activist groups such as the Humane Society of the United States, the Animal Legal Defense Fund, L214 and FOUR PAWS contend that foie gras production methods, and force feeding in particular, constitute cruel and inhumane treatment of animals. Specific complaints include livers swollen to up to ten times their normal size, impaired liver function, expansion of the abdomen making it difficult for birds to walk, death if the force feeding is continued, and scarring of the esophagus.
In modern gavage-based foie gras production, force feeding takes place 10.5–15 days or more before slaughter, depending on species (duck or goose) and production methods.
In 2001, the Director of the New York State Government Affairs & Public Policy Dept. for the American Society for the Prevention of Cruelty to Animals, which is one of America's leading environmental activist groups, wrote a letter to then NYS Attorney General, Eliot Spitzer, asking that the state's foie gras producers be prosecuted for violating animal cruelty statutes.
Late in 2003, the French group Stopgavage ("Citizens' Initiative for the banning of force-feeding") published the Proclamation for the Abolition of Force Feeding, which asks justices to find foie gras production practices a violation of existing animal welfare laws. For this manifesto Stopgavage claims the support of over eighty French animal rights and welfare associations, over a hundred such associations from 25 other countries, and over 20 thousand individual signatories.
|
https://en.wikipedia.org/wiki/American%20Society%20for%20Mass%20Spectrometry | The American Society for Mass Spectrometry (ASMS) is a professional association based in the United States that supports the scientific field of mass spectrometry. As of 2018, the society had approximately 10,000 members primarily from the US, but also from around the world. The society holds a large annual meeting, typically in late May or early June as well as other topical conferences and workshops. The society publishes the Journal of the American Society for Mass Spectrometry.
Awards
The Society recognizes achievements and promotes academic research through four annual awards. The Biemann Medal and the John B. Fenn Award for a Distinguished Contribution in Mass Spectrometry both are awarded in recognition of singular achievements or contributions in fundamental or applied mass spectrometry, with the Biemann Medal being focused on individuals who are early in their careers. The Ronald A. Hites Award is awarded for outstanding original research demonstrated in papers published in the Journal of the American Society for Mass Spectrometry. The Research Awards are given to young scientists in mass spectrometry, based on the evaluation of their proposed research.
Publications
Journal of the American Society for Mass Spectrometry
Measuring Mass: From Positive Rays to Proteins
Past presidents
The past presidents of ASMS are:
Conferences
The Society holds an annual conference in late May or early June as well as topical conferences (at Asilomar State Beach in California and Sanibel Island, Florida) and a fall workshop, which is also focused on a single topic. Conferences on Mass Spectrometry and Allied Topics have been held yearly since 1953.
See also
International Mass Spectrometry Foundation
List of female mass spectrometrists |
https://en.wikipedia.org/wiki/Dynamic%20Markov%20compression | Dynamic Markov compression (DMC) is a lossless data compression algorithm developed by Gordon Cormack and Nigel Horspool. It uses predictive arithmetic coding similar to prediction by partial matching (PPM), except that the input is predicted one bit at a time (rather than one byte at a time). DMC has a good compression ratio and moderate speed, similar to PPM, but requires somewhat more memory and is not widely implemented. Some recent implementations include the experimental compression programs hook by Nania Francesco Antonio, ocamyd by Frank Schwellinger, and as a submodel in paq8l by Matt Mahoney. These are based on the 1993 implementation in C by Gordon Cormack.
Algorithm
DMC predicts and codes one bit at a time. It differs from PPM in that it codes bits rather than bytes, and from context mixing algorithms such as PAQ in that there is only one context per prediction. The predicted bit is then coded using arithmetic coding.
Arithmetic coding
A bitwise arithmetic coder such as DMC has two components, a predictor and an arithmetic coder. The predictor accepts an n-bit input string x = x1x2...xn and assigns it a probability p(x), expressed as a product of a series of predictions, p(x1)p(x2|x1)p(x3|x1x2) ... p(xn| x1x2...xn–1). The arithmetic coder maintains two high precision binary numbers, plow and phigh, representing the possible range for the total probability that the model would assign to all strings lexicographically less than x, given the bits of x seen so far. The compressed code for x is px, the shortest bit string representing a number between plow and phigh. It is always possible to find a number in this range no more than one bit longer than the Shannon limit, log2 1 / p(x). One such number can be obtained from phigh by dropping all of the trailing bits after the first bit that differs from plow.
Compression proceeds as follows. The initial range is set to plow = 0, phigh = 1. For each bit, the predictor estimates p0 = p(xi = 0|x |
https://en.wikipedia.org/wiki/Discrete%20exterior%20calculus | In mathematics, the discrete exterior calculus (DEC) is the extension of the exterior calculus to discrete spaces including graphs, finite element meshes, and lately also general polygonal meshes (non-flat and non-convex). DEC methods have proved to be very powerful in improving and analyzing finite element methods: for instance, DEC-based methods allow the use of highly non-uniform meshes to obtain accurate results. Non-uniform meshes are advantageous because they allow the use of large elements where the process to be simulated is relatively simple, as opposed to a fine resolution where the process may be complicated (e.g., near an obstruction to a fluid flow), while using less computational power than if a uniformly fine mesh were used.
The discrete exterior derivative
Stokes' theorem relates the integral of a differential (n − 1)-form ω over the boundary ∂M of an n-dimensional manifold M to the integral of dω (the exterior derivative of ω, and a differential n-form on M) over M itself:
One could think of differential k-forms as linear operators that act on k-dimensional "bits" of space, in which case one might prefer to use the bracket notation for a dual pairing. In this notation, Stokes' theorem reads as
In finite element analysis, the first stage is often the approximation of the domain of interest by a triangulation, T. For example, a curve would be approximated as a union of straight line segments; a surface would be approximated by a union of triangles, whose edges are straight line segments, which themselves terminate in points. Topologists would refer to such a construction as a simplicial complex. The boundary operator on this triangulation/simplicial complex T is defined in the usual way: for example, if L is a directed line segment from one point, a, to another, b, then the boundary ∂L of L is the formal difference b − a.
A k-form on T is a linear operator acting on k-dimensional subcomplexes of T; e.g., a 0-form assigns values to points, and ext |
https://en.wikipedia.org/wiki/Blu-ray | Blu-ray (Blu-ray Disc or BD) is a digital optical disc data storage format designed to supersede the DVD format. It was invented and developed in 2005 and released worldwide on June 20, 2006, capable of storing several hours of high-definition video (HDTV 720p and 1080p). The main application of Blu-ray is as a medium for video material such as feature films and for the physical distribution of video games for the PlayStation 3, PlayStation 4, PlayStation 5, Xbox One, and Xbox Series X. The name refers to the blue laser (actually a violet laser) used to read the disc, which allows information to be stored at a greater density than is possible with the longer-wavelength red laser used for DVDs.
The polycarbonate disc is in diameter and thick, the same size as DVDs and CDs. Conventional (or "pre-BD-XL") Blu-ray Discs contain 25 GB per layer, with dual-layer discs (50 GB) being the industry standard for feature-length video discs. Triple-layer discs (100 GB) and quadruple-layer discs (128 GB) are available for BD-XL re-writer drives.
High-definition (HD) video may be stored on Blu-ray Discs with up to pixel resolution, at 24& 50/60 progressive or 50/60 interlaced frames per second. DVD discs were limited to a maximum resolution of 480 (NTSC, 720×480 pixels) or 576 lines (CCIR 625/50, 720×576 pixels, commonly used with PAL). Besides these hardware specifications, Blu-ray is associated with a set of multimedia formats.
The BD format was developed by the Blu-ray Disc Association, a group representing makers of consumer electronics, computer hardware, and motion pictures. Sony unveiled the first Blu-ray Disc prototypes in October 2000, and the first prototype player was released in Japan in April 2003. Afterward, it continued to be developed until its official worldwide release on June 20, 2006, beginning the high-definition optical disc format war, where Blu-ray Disc competed with the HD DVD format. Toshiba, the main company supporting HD DVD, conceded in February 2 |
https://en.wikipedia.org/wiki/Martin%20measure | In descriptive set theory, the Martin measure is a filter on the set of Turing degrees of sets of natural numbers, named after Donald A. Martin. Under the axiom of determinacy it can be shown to be an ultrafilter.
Definition
Let be the set of Turing degrees of sets of natural numbers. Given some equivalence class , we may define the cone (or upward cone) of as the set of all Turing degrees such that ; that is, the set of Turing degrees that are "at least as complex" as under Turing reduction. In order-theoretic terms, the cone of is the upper set of .
Assuming the axiom of determinacy, the cone lemma states that if A is a set of Turing degrees, either A includes a cone or the complement of A contains a cone. It is similar to Wadge's lemma for Wadge degrees, and is important for the following result.
We say that a set of Turing degrees has measure 1 under the Martin measure exactly when contains some cone. Since it is possible, for any , to construct a game in which player I has a winning strategy exactly when contains a cone and in which player II has a winning strategy exactly when the complement of contains a cone, the axiom of determinacy implies that the measure-1 sets of Turing degrees form an ultrafilter.
Consequences
It is easy to show that a countable intersection of cones is itself a cone; the Martin measure is therefore a countably complete filter. This fact, combined with the fact that the Martin measure may be transferred to by a simple mapping, tells us that is measurable under the axiom of determinacy. This result shows part of the important connection between determinacy and large cardinals. |
https://en.wikipedia.org/wiki/American%20Association%20of%20Neuropathologists | American Association of Neuropathologists, Inc. was established in the 1930s as a professional and educational organization representing American neuropathologists. It was incorporated in the State of Pennsylvania in May 1960. Currently, the membership consists of 800 scientists and physicians, many of whom are international members. The AANP's expressed purpose is to advance the science and practice of neuropathology. Its official journal is the Journal of Neuropathology & Experimental Neurology. |
https://en.wikipedia.org/wiki/Hypertranscendental%20function | A hypertranscendental function or transcendentally transcendental function is a transcendental analytic function which is not the solution of an algebraic differential equation with coefficients in (the integers) and with algebraic initial conditions.
History
The term 'transcendentally transcendental' was introduced by E. H. Moore in 1896; the term 'hypertranscendental' was introduced by D. D. Morduhai-Boltovskoi in 1914.
Definition
One standard definition (there are slight variants) defines solutions of differential equations of the form
,
where is a polynomial with constant coefficients, as algebraically transcendental or differentially algebraic. Transcendental functions which are not algebraically transcendental are transcendentally transcendental. Hölder's theorem shows that the gamma function is in this category.
Hypertranscendental functions usually arise as the solutions to functional equations, for example the gamma function.
Examples
Hypertranscendental functions
The zeta functions of algebraic number fields, in particular, the Riemann zeta function
The gamma function (cf. Hölder's theorem)
Transcendental but not hypertranscendental functions
The exponential function, logarithm, and the trigonometric and hyperbolic functions.
The generalized hypergeometric functions, including special cases such as Bessel functions (except some special cases which are algebraic).
Non-transcendental (algebraic) functions
All algebraic functions, in particular polynomials.
See also
Hypertranscendental number
Notes |
https://en.wikipedia.org/wiki/Morrie%27s%20law | Morrie's law is a special trigonometric identity. Its name is due to the physicist Richard Feynman, who used to refer to the identity under that name. Feynman picked that name because he learned it during his childhood from a boy with the name Morrie Jacobs and afterwards remembered it for all of his life.
Identity and generalisation
It is a special case of the more general identity
with n = 3 and α = 20° and the fact that
since
Similar identities
A similar identity for the sine function also holds:
Moreover, dividing the second identity by the first, the following identity is evident:
Proof
Geometric proof of Morrie's law
Consider a regular nonagon with side length and let be the midpoint of , the midpoint and the midpoint of . The inner angles of the nonagon equal and furthermore , and (see graphic). Applying the cosinus definition in the right angle triangles , and then yields the proof for Morrie's law:
Algebraic proof of the generalised identity
Recall the double angle formula for the sine function
Solve for
It follows that:
Multiplying all of these expressions together yields:
The intermediate numerators and denominators cancel leaving only the first denominator, a power of 2 and the final numerator. Note that there are n terms in both sides of the expression. Thus,
which is equivalent to the generalization of Morrie's law. |
https://en.wikipedia.org/wiki/Friend%20function | In object-oriented programming, a friend function, that is a "friend" of a given class, is a function that is given the same access as methods to private and protected data.
A friend function is declared by the class that is granting access, so friend functions are part of the class interface, like methods. Friend functions allow alternative syntax to use objects, for instance f(x) instead of x.f(), or g(x,y) instead of x.g(y). Friend functions have the same implications on encapsulation as methods.
A similar concept is that of friend class.
Use cases
This approach may be used in friendly function when a function needs to access private data in objects from two different classes.
This may be accomplished in two similar ways:
A function of global or namespace scope may be declared as friend of both classes.
A member function of one class may be declared as friend of another one.
// C++ implementation of friend functions.
#include <iostream>
using namespace std;
class Foo; // Forward declaration of class Foo in order for example to compile.
class Bar {
private:
int a = 0;
public:
void show(Bar& x, Foo& y);
friend void show(Bar& x, Foo& y); // declaration of global friend
};
class Foo {
private:
int b = 6;
public:
friend void show(Bar& x, Foo& y); // declaration of global friend
friend void Bar::show(Bar& x, Foo& y); // declaration of friend from other class
};
// Definition of a member function of Bar; this member is a friend of Foo
void Bar::show(Bar& x, Foo& y) {
cout << "Show via function member of Bar" << endl;
cout << "Bar::a = " << x.a << endl;
cout << "Foo::b = " << y.b << endl;
}
// Friend for Bar and Foo, definition of global function
void show(Bar& x, Foo& y) {
cout << "Show via global function" << endl;
cout << "Bar::a = " << x.a << endl;
cout << "Foo::b = " << y.b << endl;
}
int main() {
Bar a;
Foo b;
show(a,b);
a.show(a,b);
} |
https://en.wikipedia.org/wiki/Quaternion-K%C3%A4hler%20symmetric%20space | In differential geometry, a quaternion-Kähler symmetric space or Wolf space is a quaternion-Kähler manifold which, as a Riemannian manifold, is a Riemannian symmetric space. Any quaternion-Kähler symmetric space with positive Ricci curvature is compact and simply connected, and is a Riemannian product of quaternion-Kähler symmetric spaces associated to compact simple Lie groups.
For any compact simple Lie group G, there is a unique G/H obtained as a quotient of G by a subgroup
Here, Sp(1) is the compact form of the SL(2)-triple associated with the highest root of G, and K its centralizer in G. These are classified as follows.
The twistor spaces of quaternion-Kähler symmetric spaces are the homogeneous holomorphic contact manifolds, classified by Boothby: they are the adjoint varieties of the complex semisimple Lie groups.
These spaces can be obtained by taking a projectivization of
a minimal nilpotent orbit of the respective complex Lie group.
The holomorphic contact structure is apparent, because
the nilpotent orbits of semisimple Lie groups
are equipped with the Kirillov-Kostant holomorphic symplectic form. This argument also explains how one
can associate a unique Wolf space to each of the simple
complex Lie groups.
See also
Quaternionic discrete series representation |
https://en.wikipedia.org/wiki/Renal%20dysplasia-limb%20defects%20syndrome | Renal dysplasia-limb defects syndrome (RL syndrome), also known as Ulbright–Hodes syndrome, is a very rare autosomal recessive congenital disorder. It has been described in three infants, all of whom died shortly after birth.
Presentation
RL syndrome is characterized by renal dysplasia, growth retardation, phocomelia or mesomelia, radiohumeral fusion (joining of radius and humerus), rib abnormalities, anomalies of the external genitalia and potter-like facies among many others.
Genetics
RL syndrome is inherited in an autosomal recessive manner. This means the defective gene responsible for the disorder is located on an autosome, and two copies of the defective gene (one inherited from each parent) are required in order to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.
Diagnosis
Treatment |
https://en.wikipedia.org/wiki/Comparative%20Tracking%20Index | The Comparative Tracking Index (CTI) is used to measure the electrical breakdown (tracking) properties of an insulating material. Tracking is an electrical breakdown on the surface of an insulating material wherein an initial exposure to electrical arcing heat carbonizes the material. The carbonized areas are more conductive than the pristine insulator, increasing current flow, resulting in increased heat generation, and eventually the insulation becomes completely conductive.
Details
A large voltage difference gradually creates a conductive leakage path across the surface of the material by forming a carbonized track. Testing method is specified in IEC standard 60112 and ASTM D3638.
To measure the tracking, 50 drops of 0.1% ammonium chloride solution are dropped on the material, and the voltage measured for a 3 mm thickness is considered representative of the material performance. Also term PTI (Proof Tracking Index) is used: it means voltage at which during testing on five samples the samples pass the test with no failures.
Performance Level Categories (PLC) were introduced to avoid excessive implied precision and bias.
The CTI value is used for electrical safety assessment of electrical apparatus, as for instance carried out by testing and certification laboratories. The minimum required creepage distances over an insulating material between electrically conducting parts in apparatus, especially between parts with a high voltage and parts that can be touched by human users, is dependent on the insulator's CTI value. Also for internal distances in an apparatus by maintaining CTI based distances, the risk of fire is reduced.
Creepage distance requirement depends on the CTI. Material which CTI is unknown are classified in IIIb group. There are no CTI requirement for glass, ceramic, and other inorganic material which do not breakdown on the surface.
The better the insulation, the higher the CTI (positive relationship). In terms of clearance, a higher CTI value |
https://en.wikipedia.org/wiki/Umbilical%20cord%20ulceration%20and%20intestinal%20atresia | Umbilical cord ulceration and intestinal atresia is a rare congenital disease that leads to intestinal atresia, umbilical cord ulceration and severe intrauterine haemorrhage. Only 15 cases have so far been reported, though newer studies are beginning to conclude that this disease has a higher incidence rate than has been previously reported. A particular study has given intestinal atresia and umbilical cord ulceration a clear link after 5 such cases were reported at the time of publication. |
https://en.wikipedia.org/wiki/Multiplicity%20%28chemistry%29 | In spectroscopy and quantum chemistry, the multiplicity of an energy level is defined as 2S+1, where S is the total spin angular momentum. States with multiplicity 1, 2, 3, 4, 5 are respectively called singlets, doublets, triplets, quartets and quintets.
In the ground state of an atom or molecule, the unpaired electrons usually all have parallel spin. In this case the multiplicity is also equal to the number of unpaired electrons plus one.
Atoms
The multiplicity is often equal to the number of possible orientations of the total spin relative to the total orbital angular momentum L, and therefore to the number of near–degenerate levels that differ only in their spin–orbit interaction energy.
For example, the ground state of a carbon atom is 3P (Term symbol). The superscript three (read as triplet) indicates that the multiplicity 2S+1 = 3, so that the total spin S = 1. This spin is due to two unpaired electrons, as a result of Hund's rule which favors the single filling of degenerate orbitals. The triplet consists of three states with spin components +1, 0 and –1 along the direction of the total orbital angular momentum, which is also 1 as indicated by the letter P. The total angular momentum quantum number J can vary from L+S = 2 to L–S = 0 in integer steps, so that J = 2, 1 or 0.
However the multiplicity equals the number of spin orientations only if S ≤ L. When S > L there are only 2L+1 orientations of total angular momentum possible, ranging from S+L to S-L. The ground state of the nitrogen atom is a 4S state, for which 2S + 1 = 4 in a quartet state, S = 3/2 due to three unpaired electrons. For an S state, L = 0 so that J can only be 3/2 and there is only one level even though the multiplicity is 4.
Molecules
Most stable organic molecules have complete electron shells with no unpaired electrons and therefore have singlet ground states. This is true also for inorganic molecules containing only main-group elements. Important exceptions are dioxygen (O2) as well |
https://en.wikipedia.org/wiki/Swiss%20Vapeur%20Parc | The Swiss Vapeur Parc is a miniature park in Le Bouveret, a village on Lac Léman, Switzerland. It was opened on June 6, 1989, by an International Festival of Steam (therefore steam trains). When the park opened its total surface area was 9000 m2 (2.2 acres), but the park expanded and as of 2007, the park covers a surface area of 17'000 m2 (or 4.2 acres). In 1989, the park possessed only 2 locomotives (one running on benzine and one on steam). As of 2007, the number of trains running on benzine has sextupled while the number of steam trains has increased to 9 trains. By March 31, 2007, the Park has had 2'126'000 visitors.
Every June the park is host to the International Steam Festival.
Image gallery
External links
The Official Website
Press Communique 2007
Tourist attractions in Valais
Amusement parks in Switzerland
1989 establishments in Switzerland
Buildings and structures in Valais
Miniature parks
Amusement parks opened in 1989
20th-century architecture in Switzerland |
https://en.wikipedia.org/wiki/SecureLog | In cryptology, SecureLog is an algorithm used to convert digital data into trusted data that can be verified if the authenticity is questioned. SecureLog is used in IT solutions that generates data to support compliance regulations like SOX.
History
An algorithm used to make datalogs secure from manipulation. The first infrastructure supporting the algorithm was available on the Internet in 2006.
Operation
SecureLog involves an active key provider, a managed data store and a verification provider.
Active Key Provider
An active key provider distributes active keys to subscribers. An active key contains encrypted data representing time and a private secret. An active key has a validity period that is set by the active key provider.
Managed data store
The managed data store is a subscriber to the active keys delivered by the active key provider. The managed data store uses the active keys to do asymmetric encryption, timestamping and archive the data into a locked database.
Verification provider
The verification provider may read segments from the locked database and verify content, timestamps and that the integrity of the data has not been broken or manipulated since it was saved.
Uses
The algorithm is used in several different use cases:
Compliance issues
SecureLog is used to secure different types of data logs like access logs, email archives or transaction logs and is primarily in use where compliance might be an issue.
The administrator weak link problem
One drawback with archiving solutions is that there is always an administrator that in the end has access to the information. This makes it difficult to trust the integrity of the data. SecureLog is used to solve the traditional administrator problem.
Proposed uses
Government use
In the public sector several laws handles the archiving of data. It has been proposed that SecureLog can be used by a free institution to lock government logs and stop them from potential manipulation. Several potential use cases |
https://en.wikipedia.org/wiki/Phytoecdysteroid | Phytoecdysteroids are plant-derived ecdysteroids. Phytoecdysteroids are a class of chemicals that plants synthesize for defense against phytophagous (plant eating) insects. These compounds are mimics of hormones used by arthropods in the molting process known as ecdysis. When insects eat the plants with these chemicals they may prematurely molt, lose weight, or suffer other metabolic damage and die.
Chemically, phytoecdysteroids are classed as triterpenoids, the group of compounds that includes triterpene saponins, phytosterols, and phytoecdysteroids. Plants, but not animals, synthesize phytoecdysteroids from mevalonic acid in the mevalonate pathway of the plant cell using acetyl-CoA as a precursor.
Over 250 ecdysteroid analogs have been identified so far in plants, and it has been theorized that there are over 1,000 possible structures which might occur in nature. Many more plants have the ability to "turn on" the production of phytoecdysteroids when under stress, animal attack or other conditions.
The term phytoecdysteroid can also apply to ecdysteroids found in fungi, even though fungi are not plants.
Some plants or fungi that produce phytoecdysteroids include Achyranthes bidentata, Tinospora cordifolia, Pfaffia paniculata, Leuzea carthamoides, Rhaponticum uniflorum, Serratula coronata, Cordyceps, and Asparagus.
See also
Plant defense against herbivory |
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