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https://en.wikipedia.org/wiki/MECP2
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MECP2 (methyl CpG binding protein 2) is a gene that encodes the protein MECP2. MECP2 appears to be essential for the normal function of nerve cells. The protein seems to be particularly important for mature nerve cells, where it is present in high levels. The MECP2 protein is likely to be involved in turning off ("repressing" or "silencing") several other genes. This prevents the genes from making proteins when they are not needed. Recent work has shown that MECP2 can also activate other genes. The MECP2 gene is located on the long (q) arm of the X chromosome in band 28 ("Xq28"), from base pair 152,808,110 to base pair 152,878,611.
MECP2 is an important reader of DNA methylation. Its methyl-CpG-binding (MBD) domain recognizes and binds 5-mC regions. MECP2 is X-linked and subject to X inactivation. MECP2 gene mutations are the cause of most cases of Rett syndrome, a progressive neurologic developmental disorder and one of the most common causes of cognitive disability in females. At least 53 disease-causing mutations in this gene have been discovered.
Function
MECP2 protein is found in all cells in the body, including the brain, acting as a transcriptional repressor and activator, depending on the context. However, the idea that MECP2 functions as an activator is relatively new and remains controversial. In the brain, it is found in high concentrations in neurons and is associated with maturation of the central nervous system (CNS) and in forming synaptic contacts.
Mech
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https://en.wikipedia.org/wiki/Asymptote%20%28vector%20graphics%20language%29
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Asymptote is a descriptive vector graphics language – developed by Andy Hammerlindl, John C. Bowman (University of Alberta), and Tom Prince – which provides a natural coordinate-based framework for technical drawing. Asymptote runs on all major platforms (Unix, Mac OS, Microsoft Windows). It is free software, available under the terms of the GNU Lesser General Public License (LGPL).
Syntax and notable features
Asymptote typesets labels and equations with LaTeX, producing high-quality PostScript, PDF, SVG, or 3D PRC output. It is inspired by MetaPost, but has a C++-like syntax. It provides a language for typesetting mathematical figures, just as TeX/LaTeX provides a language for typesetting equations. It is mathematically oriented (e.g. rotation of vectors by complex multiplication), and uses the simplex method and deferred drawing to solve overall size constraint issues between fixed-sized objects (labels and arrowheads) and objects that should scale with figure size.
Asymptote fully generalizes MetaPost path construction algorithms to three dimensions, and compiles commands into virtual machine code for speed without sacrificing portability. High-level graphics commands are implemented in the Asymptote language itself, allowing them to be easily tailored to specific applications. It also appears to be the first software package to lift TeX into three dimensions.
This allows Asymptote to be used as a 3D vector file format.
Asymptote is also notable for having a graphical
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https://en.wikipedia.org/wiki/Zener%20pinning
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Zener pinning is the influence of a dispersion of fine particles on the movement of low- and high-angle grain boundaries through a polycrystalline material. Small particles act to prevent the motion of such boundaries by exerting a pinning pressure which counteracts the driving force pushing the boundaries. Zener pinning is very important in materials processing as it has a strong influence on recovery, recrystallization and grain growth.
Origin of the pinning force
A boundary is an imperfection in the crystal structure and as such is associated with a certain quantity of energy. When a boundary passes through an incoherent particle then the portion of boundary that would be inside the particle essentially ceases to exist. In order to move past the particle some new boundary must be created, and this is energetically unfavourable. While the region of boundary near the particle is pinned, the rest of the boundary continues trying to move forward under its own driving force. This results in the boundary becoming bowed between those points where it is anchored to the particles.
Mathematical description
The figure illustrates a boundary intersecting with an incoherent particle of radius . The pinning force acts along the line of contact between the boundary and the particle, i.e., a circle of diameter . The force per unit length of boundary in contact is , where is the interfacial energy. Hence, the total force acting on the particle-boundary interface is
The maximum restr
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https://en.wikipedia.org/wiki/Classification%20Markup%20Language
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Classification Markup Language (ClaML) is an XML data format specification meant for the exchange of medical classifications, which are code numbers for of medical diagnoses and procedures.
The ClaML specification has first been published as Technical Specification CEN/TS 14463:2003, a 2007 revision of ClaML has been accepted as European Norm EN 14463:2007, which was replaced by ISO 13120:2013.
The ClaML standard has been prepared by Working Group 3 (Semantic Content) of the International Organization for Standardization's (ISO) Technical Committee (TC) on health informatics, known as ISO/TC 215 WG3.
ClaML has been adopted by the WHO to distribute their family of international classifications.
Specifications availability
As a CEN standard, the ClaML specification is available from the various European national standardisation bodies, and can be found via the CEN website. The specification document includes the Document Type Definition (DTD). The DTD can be separately downloaded here DTD ClaML. An unofficial specification with example can be found here ClaML.
External links
ISO 13120:2019 Health informatics -- Syntax to represent the content of healthcare classification systems -- Classification Markup Language (ClaML)
ISO/TC 215 Health informatics
CEN Published Health Informatics Standards
ClaML example
Markup languages
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https://en.wikipedia.org/wiki/Recrystallization%20%28metallurgy%29
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In materials science, recrystallization is a process by which deformed grains are replaced by a new set of defect-free grains that nucleate and grow until the original grains have been entirely consumed. Recrystallization is usually accompanied by a reduction in the strength and hardness of a material and a simultaneous increase in the ductility. Thus, the process may be introduced as a deliberate step in metals processing or may be an undesirable byproduct of another processing step. The most important industrial uses are softening of metals previously hardened or rendered brittle by cold work, and control of the grain structure in the final product. Recrystallization temperature is typically 0.3–0.4 times the melting point for pure metals and 0.5 times for alloys.
Definition
Recrystallization is defined as the process in which grains of a crystal structure come in a new structure or new crystal shape.
A precise definition of recrystallization is difficult to state as the process is strongly related to several other processes, most notably recovery and grain growth. In some cases it is difficult to precisely define the point at which one process begins and another ends. Doherty et al. (1997) defined recrystallization as:
"... the formation of a new grain structure in a deformed material by the formation and migration of high angle grain boundaries driven by the stored energy of deformation. High angle boundaries are those with greater than a 10-15° misorientation"
Thus t
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https://en.wikipedia.org/wiki/Gerald%20Schatten
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Gerald Schatten (born 1949) is an American stem cell researcher with interests in cell, developmental, and reproductive biology. He is Professor and vice-chair of Obstetrics, Gynecology and Reproductive Sciences and Professor of Cell Biology and of Bioengineering in the Schools of Medicine and Engineering at the University of Pittsburgh, where he is also Director of the Division of Developmental and Regenerative Medicine at the university's School of Medicine. Additionally, he is deputy director of the Magee-Women's Research Institute and Director of the Pittsburgh Development Center.. He is a member of the NCI-designated University of Pittsburgh Cancer Center and the McGowan Institute for Regenerative Medicine.
Early life and education
Schatten was born in 1949 in New York City and was educated in the public school system, including at Stuyvesant High School. He graduated with an A.B. in Zoology from the University of California, Berkeley in 1971, where he also obtained his Ph.D. in Cell and Developmental Biology.
Academic career
Schatten was awarded a Rockefeller Foundation Postdoctoral Fellowship for 1976–1977 to conduct mentored research under the direction of Daniel Mazia at UC Berkeley. He was also awarded a postdoctoral fellowship at the German Cancer Research Center.
1976-1985 he was assistant professor, associate professor, Full Professor of Biological Sciences and Molecular Biophysics at Florida State University; while there, he received a National Institutes
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https://en.wikipedia.org/wiki/ABCA12
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ATP-binding cassette sub-family A member 12 also known as ATP-binding cassette transporter 12 is a protein that in humans is encoded by the ABCA12 gene.
ABCA12 belongs to a group of genes called the ATP-binding cassette family, which makes proteins that transport molecules across cell membranes. The ABCA12 gene is active in some types of skin cells and in several other tissues, such as testis, placenta, lung, stomach, and fetal brain and liver. This protein appears to be essential for normal development of the skin, which provides a barrier between the body and its surrounding environment. It transports epidermoside, a glucosylceramide, out of the keratinocytes of the stratum corneum of the epidermis.
The ABCA12 gene is located on the long (q) arm of chromosome 2 between positions 34 and 35, from base pair 215,621,772 to base pair 215,828,656.
Clinical significance
Harlequin-type ichthyosis
Several mutations in the ABCA12 gene are known to cause harlequin-type ichthyosis. Most of these mutations are predicted to lead to an absence of ABCA12 protein or the production of an extremely small version of the protein that cannot transport lipids properly. A loss of functional ABCA12 protein causes numerous problems with the development of the epidermis before and after birth. Abnormalities in lipid transport prevent the skin from forming an effective barrier and result in the hard, thick scales characteristic of harlequin ichthyosis.
Lamellar ichthyosis type 2
Mutations in t
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https://en.wikipedia.org/wiki/GRENOUILLE
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Grating-eliminated no-nonsense observation of ultrafast incident laser light e-fields (GRENOUILLE) is an ultrashort pulse measurement technique based on frequency-resolved optical gating (FROG). The acronym was chosen because of the technique's relationship to FROG; grenouille is French for frog.
Theory
Because most FROG techniques have an autocorrelator, they also have the sensitive alignment issues that come with it. In addition, most FROGs use a thin second-harmonic generation (SHG) crystal and a spectrometer, adding signal strength requirements as well as additional alignment issues. GRENOUILLE is a simple device based on the SHG FROG, replacing the beam splitter, delay line and beam recombination components of the autocorrelator with a prism, and replacing the spectrometer and thin SHG crystal combination with a thick SHG crystal. The effect of these replacements is to eliminate all sensitive alignment parameters while increasing the signal strength. These changes also reduce the complexity and cost of this type of system. However, like the previous systems, GRENOUILLE still determines the full phase and intensity data of a pulse and produces traces identical in form to those from SHG FROG.
A typical GRENOUILLE setup used with a theoretical square input beam can be seen above. The first element, a horizontal cylindrical lens, is used to tightly focus the incoming signal beam into a horizontal stripe at the thick SHG crystal in order to yield a range of crystal incidenc
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https://en.wikipedia.org/wiki/ACADM
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ACADM (acyl-Coenzyme A dehydrogenase, C-4 to C-12 straight chain) is a gene that provides instructions for making an enzyme called acyl-coenzyme A dehydrogenase that is important for breaking down (degrading) a certain group of fats called medium-chain fatty acids.
These fatty acids are found in foods such as milk and certain oils, and they are also stored in the body's fat tissue. Medium-chain fatty acids are also produced when larger fatty acids are degraded.
The acyl-coenzyme A dehydrogenase for medium-chain fatty acids (ACADM) enzyme is essential for converting these particular fatty acids to energy, especially during periods without food (fasting). The ACADM enzyme functions in mitochondria, the energy-producing centers within cells. It is found in the mitochondria of several types of tissues, particularly the liver.
The ACADM gene is located on the short (p) arm of chromosome 1 at position 31, from base pair 75,902,302 to base pair 75,941,203.
Structure
The protein encoded by the ACADM gene is ~47 kDa in size, and composed of 421 amino acids.
Function
The LCAD enzyme catalyzes most of fatty acid beta-oxidation by forming a C2-C3 trans-double bond in the fatty acid. MCAD works on long-chain fatty acids, typically between C4 and C12-acylCoA. Fatty acid oxidation has proven to spare glucose in fasting conditions, and is also required for amino acid metabolism, which is essential for the maintenance of adequate glucose production. Furthermore, MCAD participates in fat
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https://en.wikipedia.org/wiki/Gene%20product
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A gene product is the biochemical material, either RNA or protein, resulting from expression of a gene. A measurement of the amount of gene product is sometimes used to infer how active a gene is. Abnormal amounts of gene product can be correlated with disease-causing alleles, such as the overactivity of oncogenes which can cause cancer.
A gene is defined as "a hereditary unit of DNA that is required to produce a functional product". Regulatory elements include:
Promoter region
TATA box
Polyadenylation sequences
Enhancers
These elements work in combination with the open reading frame to create a functional product. This product may be transcribed and be functional as RNA or is translated from mRNA to a protein to be functional in the cell.
RNA products
RNA molecules that do not code for any proteins still maintain a function in the cell. The function of the RNA depends on its classification. These roles include:
aiding protein synthesis
catalyzing reactions
regulating various processes.
Protein synthesis is aided by functional RNA molecules such as tRNA, which helps add the correct amino acid to a polypeptide chain during translation, rRNA, a major component of ribosomes (which guide protein synthesis), as well as mRNA which carry the instructions for creating the protein product.
One type of functional RNA involved in regulation are microRNA (miRNA), which works by repressing translation. These miRNAs work by binding to a complementary target mRNA sequence to preve
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https://en.wikipedia.org/wiki/No%20Other
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No Other is the fourth solo studio album by American singer-songwriter Gene Clark. Released in September 1974, it was largely ignored or lambasted by critics and was a commercial failure; the studio time and cost were seen as excessive and indulgent. The record label, Asylum Records, did not promote the album, and by 1976 had deleted it from their catalog. Clark never recovered from the failure of the album.
Just prior to Clark's death in 1991, No Other was reissued in its entirety on CD. In 1993, an Australian CD compilation entitled American Dreamer 1964–1974 included two songs from No Other, while in 1998, a double disc compilation, Flying High, was released with three songs from No Other. Then in the early 2000s, No Other was reissued a second time in its entirety to positive critical reappraisal; publications have referred to it as "a lost masterpiece" and "one of the greatest albums ever made." A highly praised, newly remastered reissue campaign by 4AD was launched on November 8, 2019, with the album reissued as a standard CD, vinyl LP, deluxe double-CD set, and an expansive super deluxe box set with three SACDs, one Blu-ray disc, a silver-colored LP, and commemorative 80-page book.
Background
In late 1972, Clark was invited to join a reunion of the original Byrds line-up on Asylum Records. Although nominally organized and produced by David Crosby, the resulting album evolved into an inadvertent showcase for Clark, who sang lead on two Neil Young covers and two origin
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https://en.wikipedia.org/wiki/Noisy-channel%20coding%20theorem
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In information theory, the noisy-channel coding theorem (sometimes Shannon's theorem or Shannon's limit), establishes that for any given degree of noise contamination of a communication channel, it is possible to communicate discrete data (digital information) nearly error-free up to a computable maximum rate through the channel. This result was presented by Claude Shannon in 1948 and was based in part on earlier work and ideas of Harry Nyquist and Ralph Hartley.
The Shannon limit or Shannon capacity of a communication channel refers to the maximum rate of error-free data that can theoretically be transferred over the channel if the link is subject to random data transmission errors, for a particular noise level. It was first described by Shannon (1948), and shortly after published in a book by Shannon and Warren Weaver entitled The Mathematical Theory of Communication (1949). This founded the modern discipline of information theory.
Overview
Stated by Claude Shannon in 1948, the theorem describes the maximum possible efficiency of error-correcting methods versus levels of noise interference and data corruption. Shannon's theorem has wide-ranging applications in both communications and data storage. This theorem is of foundational importance to the modern field of information theory. Shannon only gave an outline of the proof. The first rigorous proof for the discrete case is given in .
The Shannon theorem states that given a noisy channel with channel capacity C and
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https://en.wikipedia.org/wiki/Neuronal%20noise
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Neuronal noise or neural noise refers to the random intrinsic electrical fluctuations within neuronal networks. These fluctuations are not associated with encoding a response to internal or external stimuli and can be from one to two orders of magnitude. Most noise commonly occurs below a voltage-threshold that is needed for an action potential to occur, but sometimes it can be present in the form of an action potential; for example, stochastic oscillations in pacemaker neurons in suprachiasmatic nucleus are partially responsible for the organization of circadian rhythms.
Background
Neuronal activity at the microscopic level has a stochastic character, with atomic collisions and agitation, that may be termed "noise." While it isn't clear on what theoretical basis neuronal responses involved in perceptual processes can be segregated into a "neuronal noise" versus a "signal" component, and how such a proposed dichotomy could be corroborated empirically, a number of computational models incorporating a "noise" term have been constructed.
Single neurons demonstrate different responses to specific neuronal input signals. This is commonly referred to as neural response variability. If a specific input signal is initiated in the dendrites of a neuron, then a hypervariability exists in the number of vesicles released from the axon terminal fiber into the synapse. This characteristic is true for fibers without neural input signals, such as pacemaker neurons, as mentioned previously,
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https://en.wikipedia.org/wiki/Enzo
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Enzo is an Italian given name derivative of the German name Heinz. It can be used also as the short form for Lorenzo, Vincenzo, Innocenzo, or Fiorenzo. It is most common in the Romance-speaking world, particularly in Italy and Latin America but lately also in France, Spain and Portugal.
People
Enzo Amendola (born 1973), Italian politician
Enzo Amore (born 1986), Ring name of American professional wrestler Eric Arndt
Enzo Bearzot (1927-2010), Italian football player and manager
Enzo Benedetto (1905–1993), Italian painter
Enzo Biagi (1920–2007), Italian journalist
Enzo Calzaghe (1949–2018), Anglo-Italian boxing trainer
Enzo Cesario (born 1980), Chilean track and road cyclist
Enzo Dara (1938–2017), Italian operatic bass
Enzo Emanuele (born 1977), Italian medical researcher and editor
Enzo Fernández (born 1995), French footballer
Enzo Fernández (born 2001), Argentine footballer.
Enzo Ferrari (1898–1988), Italian race car driver, founder of Scuderia Ferrari and Ferrari S.p.A.
Enzo Ferrari (born 1942), Italian former footballer and manager
Enzo Francescoli (born 1961), Uruguayan football player
Enzo Maccarinelli (born 1980), Welsh professional boxer
Enzo Maiorca (1931-2016), Italian multiple record holder in free-diving
Enzo Maresca (born 1980), Italian football player
Enzo Mari (1932-2020), Italian artist and designer
Enzo Muccetti (1912–1977), Italian classical bassoonist
Enzo Pérez (born 1986), Argentine midfielder football player
Enzo Roco (born 1992), C
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https://en.wikipedia.org/wiki/Lindley%20equation
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In probability theory, the Lindley equation, Lindley recursion or Lindley processes is a discrete-time stochastic process An where n takes integer values and:
An + 1 = max(0, An + Bn).
Processes of this form can be used to describe the waiting time of customers in a queue or evolution of a queue length over time. The idea was first proposed in the discussion following Kendall's 1951 paper.
Waiting times
In Dennis Lindley's first paper on the subject the equation is used to describe waiting times experienced by customers in a queue with the First-In First-Out (FIFO) discipline.
Wn + 1 = max(0,Wn + Un)
where
Tn is the time between the nth and (n+1)th arrivals,
Sn is the service time of the nth customer, and
Un = Sn − Tn
Wn is the waiting time of the nth customer.
The first customer does not need to wait so W1 = 0. Subsequent customers will have to wait if they arrive at a time before the previous customer has been served.
Queue lengths
The evolution of the queue length process can also be written in the form of a Lindley equation.
Integral equation
Lindley's integral equation is a relationship satisfied by the stationary waiting time distribution F(x) in a G/G/1 queue.
Where K(x) is the distribution function of the random variable denoting the difference between the (k - 1)th customer's arrival and the inter-arrival time between (k - 1)th and kth customers. The Wiener–Hopf method can be used to solve this expression.
Notes
Queueing theory
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https://en.wikipedia.org/wiki/Magnesium%20transporter
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Magnesium transporters are proteins that transport magnesium across the cell membrane. All forms of life require magnesium, yet the molecular mechanisms of Mg2+ uptake from the environment and the distribution of this vital element within the organism are only slowly being elucidated.
The ATPase function of MgtA is highly cardiolipin dependent and has been shown to detect free magnesium in the μM range
In bacteria, Mg2+ is probably mainly supplied by the CorA protein and, where the CorA protein is absent, by the MgtE protein. In yeast the initial uptake is via the Alr1p and Alr2p proteins, but at this stage the only internal Mg2+ distributing protein identified is Mrs2p. Within the protozoa only one Mg2+ transporter (XntAp) has been identified. In metazoa, Mrs2p and MgtE homologues have been identified, along with two novel Mg2+ transport systems TRPM6/TRPM7 and PCLN-1. Finally, in plants, a family of Mrs2p homologues has been identified along with another novel protein, AtMHX.
Evolution
The evolution of Mg2+ transport appears to have been rather complicated. Proteins apparently based on MgtE are present in bacteria and metazoa, but are missing in fungi and plants, whilst proteins apparently related to CorA are present in all of these groups. The two active transport transporters present in bacteria, MgtA and MgtB, do not appear to have any homologies in higher organisms. There are also Mg2+ transport systems that are found only in the higher organisms.
Types
There a
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https://en.wikipedia.org/wiki/Combeite
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Combeite is a rare silicate mineral with the formula Na2Ca2Si3O9. It has a trigonal crystal system.
Discovery and occurrence
It was first described in 1957 for an occurrence in nephelinite lavas and tephra on Mount Nyiragongo, Goma, Kivu, Democratic Republic of Congo (then Zaïre). It has also been reported from the Bellerberg volcano in Ettringen, Germany and the Oldoinyo Lengai volcano, Tanzania. It was named for Arthur Delmar Combe of the Geological Survey of Uganda.
It is associated with götzenite at Mount Shaheru, Congo; and with wollastonite, clinopyroxene, nepheline, melilite, titanian garnet and titanian magnetite at Oldoinyo Lengai.
References
Sodium minerals
Calcium minerals
Cyclosilicates
Trigonal minerals
Minerals in space group 152 or 154
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https://en.wikipedia.org/wiki/ITFET
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The inverted-T field-effect transistor (ITFET) is a type of field effect transistor invented by Leo Mathew at Freescale Semiconductor. Part of the device extends vertically from the horizontal plane in an inverted T shape, hence the name.
References
Freescale upends thinking on transistor channels (EE Times, December 5, 2005)
Transistor types
Field-effect transistors
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https://en.wikipedia.org/wiki/Bernard%20Davis%20%28biologist%29
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Bernard David Davis (January 7, 1916 – January 14, 1994) was an American biologist who made major contributions in microbial physiology and metabolism. Davis was a prominent figure at Harvard Medical School in microbiology and in national science policy. He was the 1989 recipient of the Selman A. Waksman Award in Microbiology from the National Academy of Sciences.
Education
Davis was born in Franklin, Massachusetts, where his parents, Jewish immigrants from Lithuania, had settled. He was valedictorian at his high school, then attended Harvard University, where he majored in biochemistry. After earning his Bachelor of Science degree, he enrolled at Harvard Medical School, graduating in 1940 with a rare M.D., summa cum laude. He was elected a Fellow of the American Academy of Arts and Sciences in 1958. In a front-note to a posthumously published commentary that appeared in 2000, the major contributions of Davis to microbial physiology has been noted as, "the use of penicillin for the selection of auxotrophic mutants and his U-tube experiment to prove that bacterial conjugation required direct contact between the two bacterial strains."
Moralistic fallacy
In a short article published in Nature in 1978, Davis coined the term "moralistic fallacy" after calls for ethical guidelines to control the study of what could allegedly become "dangerous knowledge." The term was intended as a converse to the naturalistic fallacy, a term coined by G.E. Moore in the early twentieth century b
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https://en.wikipedia.org/wiki/Cohen%E2%80%93Sutherland%20algorithm
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In computer graphics, the Cohen–Sutherland algorithm is an algorithm used for line clipping. The algorithm divides a two-dimensional space into 9 regions and then efficiently determines the lines and portions of lines that are visible in the central region of interest (the viewport).
The algorithm was developed in 1967 during flight simulator work by Danny Cohen and Ivan Sutherland.
The algorithm
The algorithm includes, excludes or partially includes the line based on whether:
Both endpoints are in the viewport region (bitwise OR of endpoints = 0000): trivial accept.
Both endpoints share at least one non-visible region, which implies that the line does not cross the visible region. (bitwise AND of endpoints ≠ 0000): trivial reject.
Both endpoints are in different regions: in case of this nontrivial situation the algorithm finds one of the two points that is outside the viewport region (there will be at least one point outside). The intersection of the outpoint and extended viewport border is then calculated (i.e. with the parametric equation for the line), and this new point replaces the outpoint. The algorithm repeats until a trivial accept or reject occurs.
The numbers in the figure below are called outcodes. An outcode is computed for each of the two points in the line. The outcode will have 4 bits for two-dimensional clipping, or 6 bits in the three-dimensional case. The first bit is set to 1 if the point is above the viewport. The bits in the 2D outcode represent:
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https://en.wikipedia.org/wiki/Nicholl%E2%80%93Lee%E2%80%93Nicholl%20algorithm
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In computer graphics, the Nicholl–Lee–Nicholl algorithm is a fast algorithm for line clipping that reduces the chances of clipping a single line segment multiple times, as may happen in the Cohen–Sutherland algorithm.
Description
Using the Nicholl–Lee–Nicholl algorithm, the area around the clipping window is divided into a number of different areas, depending on the position of the initial point of the line to be clipped. This initial point should be in three predetermined areas; thus the line may have to be translated and/or rotated to bring it into the desired region. The line segment may then be re-translated and/or re-rotated to bring it to the original position. After that, straight line segments are drawn from the line end point, passing through the corners of the clipping window. These areas are then designated as L, LT, LB, or TR, depending on the location of the initial point. Then the other end point of the line is checked against these areas. If a line starts in the L area and finishes in the LT area then the algorithm concludes that the line should be clipped at xw (max). Thus the number of clipping points is reduced to one, compared to other algorithms that may require two or more clipping
See also
Algorithms used for the same purpose:
Liang–Barsky algorithm
Cyrus–Beck algorithm
Fast clipping
References
Line clipping algorithms
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https://en.wikipedia.org/wiki/Anthrone
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Anthrone is a tricyclic aromatic ketone. It is used for a common cellulose assay and in the colorimetric determination of carbohydrates.
Derivatives of anthrone are used in pharmacy as laxative. They stimulate the motion of the colon and reduce water reabsorption. Some anthrone derivatives can be extracted from a variety of plants, including Rhamnus frangula, Aloe ferox, Rheum officinale, and Cassia senna. Glycosides of anthrone are also found in high amounts in rhubarb leaves, and alongside concentrated amounts of oxalic acid are the reason for the leaves being inedible.
Synthesis and reactions
Anthrone can be prepared from anthraquinone by reduction with tin or copper.
An alternative synthesis involves cyclization of o-benzylbenzoic acid induced with hydrogen fluoride.
Anthrone condenses with glyoxal to give, following dehydrogenation, acedianthrone, a useful octacyclic pigment.
Tautomer
Anthrone is the more stable tautomer relative to the anthrol. The tautomeric equilibrium is estimated at 100 in aqueous solution. For the two other isomeric anthrols, the tautomeric equilibrium is reversed.
References
Aromatic ketones
Anthracenes
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https://en.wikipedia.org/wiki/Immunoscreening
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Immunoscreening is a method of biotechnology used to detect a polypeptide produced from a cloned gene. The term encompasses several different techniques designed for protein identification, such as Western blotting, using recombinant DNA, and analyzing antibody-peptide interactions.
Clones are screened for the presence of the gene product: the resulting protein.
This strategy requires first that a gene library is implemented in an expression vector, and that antiserum to the protein is available.
Radioactivity or an enzyme is coupled generally with the secondary
antibody.
The radioactivity/enzyme linked secondary antibody can be purchased commercially and can detect different antigens.
In commercial diagnostics labs, labelled primary antibodies are
also used. The antigen-antibody interaction is used in the immunoscreening of several diseases.
See also
ELISA
Blots
References
Biotechnology
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https://en.wikipedia.org/wiki/Anderson%E2%80%93Darling%20test
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The Anderson–Darling test is a statistical test of whether a given sample of data is drawn from a given probability distribution. In its basic form, the test assumes that there are no parameters to be estimated in the distribution being tested, in which case the test and its set of critical values is distribution-free. However, the test is most often used in contexts where a family of distributions is being tested, in which case the parameters of that family need to be estimated and account must be taken of this in adjusting either the test-statistic or its critical values. When applied to testing whether a normal distribution adequately describes a set of data, it is one of the most powerful statistical tools for detecting most departures from normality.
K-sample Anderson–Darling tests are available for testing whether several collections of observations can be modelled as coming from a single population, where the distribution function does not have to be specified.
In addition to its use as a test of fit for distributions, it can be used in parameter estimation as the basis for a form of minimum distance estimation procedure.
The test is named after Theodore Wilbur Anderson (1918–2016) and Donald A. Darling (1915–2014), who invented it in 1952.
The single-sample test
The Anderson–Darling and Cramér–von Mises statistics belong to the class of
quadratic EDF statistics (tests based on the empirical distribution function). If the hypothesized distribution is , and empiric
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https://en.wikipedia.org/wiki/Query%20optimization
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Query optimization is a feature of many relational database management systems and other databases such as NoSQL and graph databases. The query optimizer attempts to determine the most efficient way to execute a given query by considering the possible query plans.
Generally, the query optimizer cannot be accessed directly by users: once queries are submitted to the database server, and parsed by the parser, they are then passed to the query optimizer where optimization occurs. However, some database engines allow guiding the query optimizer with hints.
A query is a request for information from a database. It can be as simple as "find the address of a person with Social Security number 123-45-6789," or more complex like "find the average salary of all the employed married men in California between the ages 30 to 39 who earn less than their spouses." The result of a query is generated by processing the rows in a database in a way that yields the requested information. Since database structures are complex, in most cases, and especially for not-very-simple queries, the needed data for a query can be collected from a database by accessing it in different ways, through different data-structures, and in different orders. Each different way typically requires different processing time. Processing times of the same query may have large variance, from a fraction of a second to hours, depending on the chosen method. The purpose of query optimization, which is an automated process, is
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https://en.wikipedia.org/wiki/Crystal%20Lake%20%28Saskatchewan%29
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Crystal Lake is a lake straddling the boundary between the rural municipalities of Keys No. 303 and Buchanan No. 304 in eastern Saskatchewan, Canada. At in width and in length, it is a small lake fed by natural underground springs. It is surrounded by the residential resort community of Crystal Lake. The lake is approximately north of Canora and south-east of Preeceville.
See also
List of lakes of Saskatchewan
References
External links
Lakes of Saskatchewan
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https://en.wikipedia.org/wiki/Actun%20Tunichil%20Muknal
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Actun Tunichil Muknal (the Cave of the Crystal Sepulchre), also known locally as ATM, is a cave in Belize, near San Ignacio, Cayo District, notable as a Maya archaeological site that includes skeletons, ceramics, and stoneware. There are several areas with skeletal remains in the main chamber. The best known is "The Crystal Maiden", the skeleton of what is believed to be a 17-year-old boy, possibly a sacrifice victim, whose bones have been calcified to a sparkling, crystallized appearance.
The ceramics at the site are significant partly because they are marked with "kill holes" (holes created to release spirits lurking within), which indicate that they were used for ceremonial purposes. Many of the Maya artifacts and remains are completely calcified to the cave floor. One artifact, named the "Monkey Pot", is one of just four of its type found in Central America. The Maya also modified cave formations here, in some instances to create altars for the offerings, in others to create silhouettes of faces and animals or to project a shadow image into the cave. The cave is extensively decorated with cave formations in the upper passages.
Animal life in the cave includes a large population of bats, large freshwater crabs, crayfish, catfish and other tropical fish. Large invertebrates like amblypygi and various predatory spiders also inhabit the cave. Agouti and otters may also use the cave. These and many other species are quite common in river caves of this size in Belize.
Other
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https://en.wikipedia.org/wiki/Hierarchical%20classification
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Hierarchical classification is a system of grouping things according to a hierarchy.
In the field of machine learning, hierarchical classification is sometimes referred to as instance space decomposition, which splits a complete multi-class problem into a set of smaller classification problems.
See also
Deductive classifier
Cascading classifiers
Faceted classification
References
External links
Hierarchical Classification – a useful approach for predicting thousands of possible categories
Classification algorithms
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https://en.wikipedia.org/wiki/Tetramethrin
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Tetramethrin is a potent synthetic insecticide in the pyrethroid family. It is a white crystalline solid with a melting point of 65-80 °C. The commercial product is a mixture of stereoisomers.
It is commonly used as an insecticide, and affects the insect's nervous system. It is found in many household insecticide products.
Tetramethrin has an expected half-life of 12.5-14 days in soil and 13-25 days in water.
References
External links
Pyrethrins and Pyrethroids Fact Sheet - National Pesticide Information Center
Pyrethrins and Pyrethroids Pesticide Information Profile - Extension Toxicology Network
Maleimides
Chrysanthemate esters
Household chemicals
Isoindoles
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https://en.wikipedia.org/wiki/Jonathan%20Borden
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Jonathan Alan Borden (born October 31, 1962) is an American neurosurgeon who developed the Borden Classification of Dural Arteriovenous Fistulas. He has been involved in internet based telemedicine applications and is an editor of the RDDL specification for XML Namespaces.
Education
Borden was born on October 31, 1962, in Rochester, New York, However, he was raised in Hartford, Connecticut. Borden graduated from Amherst College in Amherst, Massachusetts with a Bachelor of Arts in Neuroscience and Yale University School of Medicine. He completed his internship and residency in Neurosurgery at Tufts University in Boston, Massachusetts.
Research
His scientific work has involved the application of computer science to neurobiology. Borden's earliest work used artificial intelligence techniques to model neurochemical networks in the brain. He used computer graphics techniques to analyze the results of molecular biological experiments. Working in the laboratory of Elias Manuelidis and Laura Manuelidis at Yale School of Medicine, he authored papers on the organization of interphase chromosomes in human brain tissue.
At Tufts-New England Medical Center he developed the Borden Classification of Dural Arteriovenous Fistulas. This classification has come into common usage after its clinical applicability has been verified by the University of Toronto Brain AVM Group
Dr. Borden was an Assistant Professor of Neurosurgery at Tufts University in Boston from 1995 to 2002. He was the dir
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https://en.wikipedia.org/wiki/Nenadkevichite
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Nenadkevichite is a rare silicate mineral containing niobium with the chemical formula . It forms brown to yellow to rose colored orthorhombic dipyramidal crystals with a dull to earthy luster. It has a Mohs hardness of 5 and a specific gravity of 2.86.
It was first reported in 1955 from a nepheline syenite pegmatite in the Kola Peninsula. In addition it has been reported from
Mont Saint-Hilaire, Canada; the Ilimaussaq complex, Greenland; Windhoek District, Namibia; and Zheltye Vody, Ukraine. It was named after Konstantin Avtonomovich Nenadkevich (1880–1963), Russian mineralogist and geochemist.
References
Webmineral data
Mindat with location data
Calcium minerals
Sodium minerals
Niobium minerals
Titanium minerals
Cyclosilicates
Orthorhombic minerals
Minerals in space group 55
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https://en.wikipedia.org/wiki/Libcwd
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Libcwd is a C++ library, written by Carlo Wood, to add run-time debugging support for C++ applications, particularly for code developed with the GNU Compiler Collection. The functionality that the library adds to an application can be divided into three categories:
Ostream-based debug output.
Run-time access to debug information.
Run-time access to memory allocation administration.
Supported platforms
Although the library code itself attempts to be strictly ISO C++, and conform to POSIX as much as possible, in order to achieve points 2 and 3, rather specialized code is needed, specific to the architecture the application runs on. Libcwd restricts itself to a narrow architecture for this reason: It has to be compiled with the GNU compiler, and demands the object code to be 32 or 64 bits ELF and the compiler generated debug information to be DWARF-2.
Compiling libcwd results in two libraries: one that is thread-safe (libcwd_r) and a version (libcwd) without thread support. The thread-safe version depends on even more architecture specific details (namely, the GNU C library). As a result, a full featured libcwd is basically only suitable for development on Linux platforms.
However, libcwd may be configured to drop thread support, memory allocation debugging and/or reading the ELF and DWARF-2 debugging information—until only the ostream debug output support is left. This way one can use it to develop an application on linux until it is robust, and still have the debug outp
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https://en.wikipedia.org/wiki/Newell%27s%20algorithm
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Newell's Algorithm is a 3D computer graphics procedure for elimination of polygon cycles in the depth sorting required in hidden surface removal. It was proposed in 1972 by brothers Martin Newell and Dick Newell, and Tom Sancha, while all three were working at CADCentre.
In the depth sorting phase of hidden surface removal, if two polygons have no overlapping extents or extreme minimum and maximum values in the x, y, and z directions, then they can be easily sorted. If two polygons, and , do have overlapping extents in the Z direction, then it is possible that cutting is necessary.
In that case, Newell's algorithm tests the following:
Test for Z overlap; implied in the selection of the face from the sort list
The extreme coordinate values in X of the two faces do not overlap (minimax test in X)
The extreme coordinate values in Y of the two faces do not overlap (minimax test in Y)
All vertices of P lie deeper than the plane of
All vertices of Q lie closer to the viewpoint than the plane of
The rasterisation of and do not overlap
The tests are given in order of increasing computational difficulty.
The polygons must be planar.
If the tests are all false, then switch the order of and in the sort, record having done so, and try again. If there is an attempt to switch the order of a polygon a second time, there is a visibility cycle, and the polygons must be split. Splitting is accomplished by selecting one polygon and cutting it along the line of intersection wi
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https://en.wikipedia.org/wiki/Phylogenomics
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Phylogenomics is the intersection of the fields of evolution and genomics. The term has been used in multiple ways to refer to analysis that involves genome data and evolutionary reconstructions. It is a group of techniques within the larger fields of phylogenetics and genomics. Phylogenomics draws information by comparing entire genomes, or at least large portions of genomes. Phylogenetics compares and analyzes the sequences of single genes, or a small number of genes, as well as many other types of data. Four major areas fall under phylogenomics:
Prediction of gene function
Establishment and clarification of evolutionary relationships
Gene family evolution
Prediction and retracing lateral gene transfer.
The ultimate goal of phylogenomics is to reconstruct the evolutionary history of species through their genomes. This history is usually inferred from a series of genomes by using a genome evolution model and standard statistical inference methods (e.g. Bayesian inference or maximum likelihood estimation).
Prediction of gene function
When Jonathan Eisen originally coined phylogenomics, it applied to prediction of gene function. Before the use of phylogenomic techniques, predicting gene function was done primarily by comparing the gene sequence with the sequences of genes with known functions. When several genes with similar sequences but differing functions are involved, this method alone is ineffective in determining function. A specific example is presented in the pap
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https://en.wikipedia.org/wiki/Memory%20bandwidth
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Memory bandwidth is the rate at which data can be read from or stored into a semiconductor memory by a processor. Memory bandwidth is usually expressed in units of bytes/second, though this can vary for systems with natural data sizes that are not a multiple of the commonly used 8-bit bytes.
Memory bandwidth that is advertised for a given memory or system is usually the maximum theoretical bandwidth. In practice the observed memory bandwidth will be less than (and is guaranteed not to exceed) the advertised bandwidth. A variety of computer benchmarks exist to measure sustained memory bandwidth using a variety of access patterns. These are intended to provide insight into the memory bandwidth that a system should sustain on various classes of real applications.
Measurement conventions
There are three different conventions for defining the quantity of data transferred in the numerator of "bytes/second":
The bcopy convention: counts the amount of data copied from one location in memory to another location per unit time. For example, copying 1 million bytes from one location in memory to another location in memory in one second would be counted as 1 million bytes per second. The bcopy convention is self-consistent, but is not easily extended to cover cases with more complex access patterns, for example three reads and one write.
The Stream convention: sums the amount of data that the application code explicitly reads plus the amount of data that the application code explic
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https://en.wikipedia.org/wiki/DBP
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DBP may refer to:
Medicine
DBP (gene), a gene coding for the D site of albumin promoter (albumin D-box) binding protein
Deathbed phenomena
Diastolic blood pressure, minimum blood pressure between two heartbeats
Vitamin D-binding protein
Science and technology
Dibutyl phthalate, a plasticizer
Digital back-propagation, a technique for compensating all fiber impairments in optical transmission systems
Disinfection by-product, a chemical occurring in water as a result of disinfection
Other
Dave Benson Phillips, a British children's TV presenter
Democratic Regions Party,(), a political party in Turkey
Deutsche Bauernpartei, former German political party
Deutsche Bundespost, former German federal post office
Development Bank of the Philippines
Dewan Bahasa dan Pustaka, a government body responsible for coordinating the use of the Malay language in Malaysia
Dewan Bahasa dan Pustaka Brunei, the official Malay-language regulator and public libraries operator in Brunei
Don Bosco Prep, all-boys Roman Catholic school in Ramsey, New Jersey
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https://en.wikipedia.org/wiki/Arneth%20count
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The Arneth count or Arneth index describes the nucleus of a type of white blood cell called a neutrophil in an attempt to detect disease.
Neutrophils typically have two or three lobes. In general, older neutrophils have more lobes than younger neutrophils. The Arneth count determines the percentage of neutrophils with one, two, three, four, and five or more lobes.
Individuals who have a larger percentage of neutrophils with fewer lobes have a left shift which can be indicative of disease processes such as infection, malignant tumors, hemolytic crises, myocardial infarction, acidosis, etc.
Individuals with a larger percentage of neutrophils with more lobes have a right shift and most commonly have diseases such as vitamin B12 or folate deficiency, chronic uremia, liver disease, etc.
The Arneth count is not commonly used in modern medicine.
It is named for Josef Arneth.
References
Blood tests
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https://en.wikipedia.org/wiki/Xifengite
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Xifengite (Fe5Si3) is a rare metallic iron silicide mineral. The crystal system of xifengite is hexagonal. It has a specific gravity of 6.45 and a Mohs hardness of 5.5. It occurs as steel gray inclusions within other meteorite derived nickel iron mineral phases.
It was first described in 1984 and named for the eastern passageway, Xifengkou, of the Great Wall of China. The type locality is the Yanshan meteorite of the Hebei Province, China. It has also been reported from dredgings along the East Pacific Rise.
The other known natural iron silicide minerals are gupeiite (), hapkeite (), linzhiite (), luobusaite (), naquite (), suessite (), and zangboite ().
See also
Glossary of meteoritics
References
Iron(II,III) minerals
Meteorite minerals
Hexagonal minerals
Minerals in space group 193
Minerals described in 1984
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https://en.wikipedia.org/wiki/Hand%20pump
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Hand pumps are manually operated pumps; they use human power and mechanical advantage to move fluids or air from one place to another. They are widely used in every country in the world for a variety of industrial, marine, irrigation and leisure activities. There are many different types of hand pump available, mainly operating on a piston, diaphragm or rotary vane principle with a check valve on the entry and exit ports to the chamber operating in opposing directions. Most hand pumps are either piston pumps or plunger pumps, and are positive displacement.
Hand pumps are commonly used in developing countries for both community supply and self-supply of water and can be installed on boreholes or hand-dug wells.
History
One sort of pump once common worldwide was a hand-powered water pump, or 'pitcher pump'. It was commonly installed over community water wells in the days before piped water supplies.
In parts of Britain and Ireland, it was often called the parish pump. Though such community pumps are no longer common, people still used the expression parish pump to describe a place or forum where matters of local interest are discussed.
Because water from pitcher pumps is drawn directly from the soil, it is more prone to contamination. If such water is not filtered and purified, consumption of it might lead to gastrointestinal or other water-borne diseases. A notorious case is the 1854 Broad Street cholera outbreak. At the time it was not known how cholera was transmitted
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https://en.wikipedia.org/wiki/Reynolds%20transport%20theorem
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In differential calculus, the Reynolds transport theorem (also known as the Leibniz–Reynolds transport theorem), or simply the Reynolds theorem, named after Osborne Reynolds (1842–1912), is a three-dimensional generalization of the Leibniz integral rule. It is used to recast time derivatives of integrated quantities and is useful in formulating the basic equations of continuum mechanics.
Consider integrating over the time-dependent region that has boundary , then taking the derivative with respect to time:
If we wish to move the derivative into the integral, there are two issues: the time dependence of , and the introduction of and removal of space from due to its dynamic boundary. Reynolds transport theorem provides the necessary framework.
General form
Reynolds transport theorem can be expressed as follows:
in which is the outward-pointing unit normal vector, is a point in the region and is the variable of integration, and are volume and surface elements at , and is the velocity of the area element (not the flow velocity). The function may be tensor-, vector- or scalar-valued. Note that the integral on the left hand side is a function solely of time, and so the total derivative has been used.
Form for a material element
In continuum mechanics, this theorem is often used for material elements. These are parcels of fluids or solids which no material enters or leaves. If is a material element then there is a velocity function , and the boundary elements obey
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https://en.wikipedia.org/wiki/Quality%20Protein%20Maize
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Quality Protein Maize (QPM) is a family of maize varieties. QPM grain contains nearly twice as much lysine and tryptophan, amino acids that are essential for humans and monogastric animals but are limiting amino acids in grains. QPM is a product of conventional plant breeding (i.e., it is not genetically modified) and an example of biofortification.
QPM was developed by Surinder Vasal and Evangelina Villegas at the International Maize and Wheat Improvement Center (CIMMYT) in the late 1990s. For their achievement, they won the 2000 World Food Prize.
Need for quality protein maize
In Central and South America, Africa, and Asia, several hundred million people rely on maize as their principal daily food, for weaning babies, and for feeding livestock. Unfortunately maize (corn) has two significant flaws; it lacks the full range of amino acids, namely lysine and tryptophan, needed to produce proteins, and has its niacin (vitamin B3) bound in an indigestible complex. The Mayans and Aztecs used to boil maize in alkaline limewater, nixtamalization, which broke down the complex so that the Niacin became available. However, in the main this practice did not transfer to the Old World or settlers in the "New World" which resulted in epidemics of Pellagra from the 16th century onwards. In addition diets high in corn produce a condition known as wet-malnutrition a person is receiving sufficient calories, but her or his body malfunctions due to a lack of protein. A chronic lack of protein
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https://en.wikipedia.org/wiki/Zaratite
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Zaratite is a bright emerald green nickel carbonate mineral with formula Ni3CO3(OH)4·4H2O. Zaratite crystallizes in the isometric crystal system as massive to mammillary encrustations and vein fillings. It has a specific gravity of 2.6 and a Mohs hardness of 3 to 3.5. It has no cleavage and is brittle to conchoidal fracture. The luster is vitreous to greasy.
It is a rare secondary mineral formed by hydration or alteration of the primary nickel and iron bearing minerals, chromite, pentlandite, pyrrhotite, and millerite, during the serpentinization of ultramafic rocks. Hellyerite, NiCO3·6H2O, is a related mineral.
It was found originally in Galicia, Spain in 1851, and named after Spanish diplomat and dramatist Antonio Gil y Zárate (1793–1861).
See also
Nickel(II) carbonate
References
Carbonate minerals
Cubic minerals
Nickel minerals
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https://en.wikipedia.org/wiki/Hellyerite
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Hellyerite, NiCO3·6(H2O), is an hydrated nickel carbonate mineral. It is light blue to bright green in colour, has a hardness of 2.5, a vitreous luster, a white streak and crystallises in the monoclinic system. The crystal habit is as platy and mammillary encrustations on its matrix.
Occurrence
The environment of formation, associated only with metamorphosed ultramafic rocks, is diagnostic compared with gaspeite, another nickel carbonate which is associated with supergene weathering of nickel sulfides.
Hellyerite is observed forming in shear planes in serpentinite, produced by carbonation of the serpentinite. Hellyerite forms in this environment in nickel rich serpentinites, which are metamorphosed equivalents of ultramafic cumulate rocks such as peridotite and dunite. Peridotite and dunite, when fresh, can contain up to ~4,000 ppm nickel within olivine.
It was first identified in 1958 in the Old Lord Brassy mine, Tasmania, Australia and named after Henry Hellyer (1791–1832), Chief Surveyor of the Van Diemens Land Company. It is also reported from the Pafuri nickel deposit in Limpopo Province, South Africa.
References
Nickel minerals
Carbonate minerals
Monoclinic minerals
Minerals in space group 15
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https://en.wikipedia.org/wiki/CDH1
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CDH1 may refer to:
Huntsville/Deerhurst Resort Airport
CDH1 (gene), classical cadherin from the cadherin superfamily
APC/C activator protein CDH1, cell-cycle regulated activator of the anaphase-promoting complex/cyclosome (APC/C)
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https://en.wikipedia.org/wiki/C91.3
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C91.3FM (ACMA callsign: 2MAC) is a commercial radio station broadcasting on the FM band at a frequency of 91.3 MHz to the Macarthur region of New South Wales in Australia. This area includes the major centres of Campbelltown and Camden. The station is owned by WIN Corporation, the parent company of WIN Television. Due to government regulations, it can only broadcast at 1 kW ERP so as to limit its broadcast area.
Many people feel that the station filled the gap left by the departure of Edge 96.1 and WSFM from Western Sydney studios. Studios for both supposed Western Sydney stations are now in North Ryde. C91.3 is the only commercial station left truly broadcasting from Western Sydney studios.
History
Originally, when it started in 2001, the station played classic rock hits, with a little bit of current pop tracks, using the positioner "The Biggest Variety of Rock & Pop". In 2004, its music format shifted more towards CHR, and with it came a change of its positioner to "The Best Music in Macarthur". In early 2006, when Rob Doorey replaced Mal Lees (formerly of Triple M's Club Veg) & Mardi Cole, both now at other stations, for its breakfast slot, their positioner was changed to "Macarthur First".
The station features former Triple M jock, Stuart Cranney. From 2001 to 2005, he presented the "Classic 9 @ 9", in which he played 9 songs with a common theme. During 2006, the 9-10am slot was taken up by the final hour of Rob Doorey's "Macarthur Breakfast" program, in which it is t
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https://en.wikipedia.org/wiki/Instituto%20de%20Biologia%20Molecular%20e%20Celular
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The Institute of Molecular and Cell Biology (IBMC - Instituto de Biologia Molecular e Celular) in Porto, Portugal, was founded in the 1990s as a multidisciplinary research institution in the fields of genetic diseases, infectious diseases and immunology, neuroscience, stress and structural biology.
Most of its investigators are University of Porto's faculty and many work also at the two university's teaching Hospitals, as well as other national biomedical and environmental research institutions, other public and private universities and a couple of enterprises. Bial, a well known Portuguese pharmaceutical company with headquarters in Porto region is one of that associated enterprises.
Its first director and co-founder was Alexandre Quintanilha.
See also
Science and technology in Portugal
External links
Official homepage
University of Porto
Research institutes in Portugal
Molecular biology institutes
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https://en.wikipedia.org/wiki/Beta-galactoside%20permease
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Galactoside permease is a protein coded by the lacY gene of the lac operon, and is found bound to the membrane of a cell for the purpose of binding galactoside molecules that have been solubilized. The protein is part of a system whose main function is to catalyze the accumulation and transport of lactose and other beta-galactosides across the permeable barrier of a membrane.
MelB carrier protein and its properties
Beta-galactoside permeases can describe any transport proteins that enable a cell to uptake, and thus accumulate, beta-galactosides. One known example of these transport proteins is the melibiose, or melB, carrier protein derived from the melB gene of E. coli. This strain of beta-galactoside permease is known it transport melibiose and other galactosides across the cell membrane using hydrogen, sodium, or lithium ions in cotransport.
Involvement of the phosphatidic acid cycle
Early studies by Hiroshi Nikaido in 1962 suggest a direct relationship between the amount of beta-galactoside permease activity in a cell and the turnover rate of phospholipids in E. coli. In his experiments with gram-positive and gram-negative bacterial cells under varying conditions, the level of P32 in phospholipids was found to be increased under conditions of maximal activity in beta-galactoside permease. Insofar, Nikaido concluded that this correlation suggested that phospholipids are involved in the process of transporting beta-galactosides through the cell membrane.
However, later
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https://en.wikipedia.org/wiki/Galactoside%20acetyltransferase
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Galactoside acetyltransferase (also known as Galactoside O-acetyltransferase, thiogalactoside transacetylase, β-galactoside transacetylase and GAT) is an enzyme that transfers an acetyl group from acetyl-CoA to β-galactosides, glucosides and lactosides. It is coded for by the lacA gene of the lac operon in E. coli.
Reaction
It catalyzes the following reaction:
acetyl-CoA + beta-D-galactoside → CoA + 6-acetyl-beta-D-galactoside
The kinetics of the enzyme were delineated in 1995.
Biological role
The enzyme's role in the classical E.coli lac operon remains unclear. However, the enzyme's cellular role may be to detoxify non-metabolizable pyranosides by acetylating them and preventing their reentry into the cell.
See also
Transacetylase
References
External links
Transferases
EC 2.3.1
Enzymes
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https://en.wikipedia.org/wiki/Sorafenib
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Sorafenib, sold under the brand name Nexavar, is a kinase inhibitor drug approved for the treatment of primary kidney cancer (advanced renal cell carcinoma), advanced primary liver cancer (hepatocellular carcinoma), FLT3-ITD positive AML and radioactive iodine resistant advanced thyroid carcinoma.
Mechanism of action
Sorafenib is a protein kinase inhibitor with activity against many protein kinases, including VEGFR, PDGFR and RAF kinases. Of the RAF kinases, sorafenib is more selective for c-Raf than B-RAF. (See BRAF (gene)#Sorafenib for details the drug's interaction with B-Raf.)
Sorafenib treatment induces autophagy, which may suppress tumor growth. Based on its 1,3-disubstituted urea structure, sorafenib is also a potent soluble epoxide hydrolase inhibitor and this activity likely reduces the severity of its adverse effects.
Medical uses
Sorafenib is indicated as a treatment for advanced renal cell carcinoma (RCC), unresectable hepatocellular carcinomas (HCC) and thyroid cancer.
Kidney cancer
Clinical trial results, published January 2007, showed that, compared with placebo, treatment with sorafenib prolongs progression-free survival in patients with advanced clear cell renal cell carcinoma in whom previous therapy has failed. The median progression-free survival was 5.5 months in the sorafenib group and 2.8 months in the placebo group (hazard ratio for disease progression in the sorafenib group, 0.44; 95% confidence interval [CI], 0.35 to 0.55; P<0.01).
In Australia
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https://en.wikipedia.org/wiki/Error%20vector%20magnitude
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The error vector magnitude or EVM (sometimes also called relative constellation error or RCE) is a measure used to quantify the performance of a digital radio transmitter or receiver. A signal sent by an ideal transmitter or received by a receiver would have all constellation points precisely at the ideal locations, however various imperfections in the implementation (such as carrier leakage, low image rejection ratio, phase noise etc.) cause the actual constellation points to deviate from the ideal locations. Informally, EVM is a measure of how far the points are from the ideal locations.
Noise, distortion, spurious signals, and phase noise all degrade EVM, and therefore EVM provides a comprehensive measure of the quality of the radio receiver or transmitter for use in digital communications. Transmitter EVM can be measured by specialized equipment, which demodulates the received signal in a similar way to how a real radio demodulator does it. One of the stages in a typical phase-shift keying demodulation process produces a stream of I-Q points which can be used as a reasonably reliable estimate for the ideal transmitted signal in EVM calculation.
Definition
An error vector is a vector in the I-Q plane between the ideal constellation point and the point received by the receiver. In other words, it is the difference between actual received symbols and ideal symbols. The root mean square (RMS) average amplitude of the error vector, normalized to ideal signal amplitude refer
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https://en.wikipedia.org/wiki/EVM
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EVM may refer to:
Earned value management in project management
Electronic voting machine
EnviroMission, an Australian energy company
Error vector magnitude, measure of radio transmission/reception
Estonian Open Air Museum (Estonian: )
Ethereum Virtual Machine, cryptocurrency scripting
Ethnoveterinary medicine
Environmental science, academic field
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https://en.wikipedia.org/wiki/Pinyin%20table
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This pinyin table is a complete listing of all Hanyu Pinyin syllables used in Standard Chinese. Each syllable in a cell is composed of an initial (columns) and a final (rows). An empty cell indicates that the corresponding syllable does not exist in Standard Chinese.
The below table indicates possible combinations of initials and finals in Standard Chinese, but does not indicate tones, which are equally important to the proper pronunciation of Chinese. Although some initial-final combinations have some syllables using each of the five different tones, most do not. Some utilize only one tone.
Pinyin entries in this page can be compared to syllables using the (unromanized) Zhuyin phonetic system in the Zhuyin table page.
Finals are grouped into subsets a, i, u and ü.
i, u and ü groupings indicate a combination of those finals with finals from Group a. For example:
Most syllables are a combination of an initial and a final. However, some syllables have no initials. This is shown in Pinyin as follows:
if the syllable begins with an i, it is replaced with a y
if the syllable begins with an u, it is replaced with a w
if the syllable begins with an ü, it is replaced with yu
exceptions to the rules above are indicated by yellow in the table's no initial column:
Note that the y, w, and yu replacements above do not change the pronunciation of the final in the final-only syllable. They are used to avoid ambiguity when writing words in pinyin. For example, instead of:
"uen" an
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https://en.wikipedia.org/wiki/Radiodiffusion-T%C3%A9l%C3%A9vision%20Fran%C3%A7aise
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Radiodiffusion-Télévision Française (RTF; French Radio and Television Broadcasting) was the French national public broadcaster television organization established on 9 February 1949 to replace the post-war "Radiodiffusion Française" (RDF), which had been founded on 23 March 1945 to replace Radiodiffusion Nationale (RN), created on 29 July 1939. It was replaced in its turn, on 26 June 1964, by the notionally less-strictly government controlled Office de Radiodiffusion Télévision Française (ORTF), which itself lasted until the end of 1974.
RTF was both state-owned and state-controlled. With a budget set by the French National Assembly under the direction of the Ministry of Information, all of its spending and investment plans had to be directly agreed by the Minister of Information and the Minister of Finance.
Alain Peyrefitte, Minister of Information, speaking in a debate in the National Assembly on 26 May 1964, described RTF as "the government in every Frenchman's dining-room" – La RTF, c'est le gouvernement dans la salle à manger de chaque Français.
History
A public monopoly on broadcasting in France had been established with the formation of Radiodiffusion Française (RDF) in 1945. RDF was renamed "Radiodiffusion-Télévision Française" (RTF) in 1949 and ORTF in 1964.
From the beginning, the public broadcaster experienced fierce competition from the "peripheral stations": French-speaking stations aimed at the French public but transmitting on longwave from neighbouring cou
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https://en.wikipedia.org/wiki/TPDF
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TPDF may refer to:
Tanzania People's Defence Force
Triangular Probability Density Function, a type of distribution which is used in audio dithering
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https://en.wikipedia.org/wiki/Porphyroblast
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A porphyroblast is a large mineral crystal in a metamorphic rock which has grown within the finer grained matrix. Porphyroblasts are commonly euhedral crystals, but can also be partly to completely irregular in shape.
The most common porphyroblasts in metapelites (metamorphosed mudstones and siltstones) are garnets and staurolites, which stand out in well-foliated metapelites (such as schists) against the platy mica matrix.
A similar type of crystal is a phenocryst, a large crystal in an igneous rock. Porphyroblasts are often confused with porphyroclasts, which can also be large outstanding crystals, but which are older than the matrix of the rock.
If a porphyroblastic mineral has small inclusions of minerals within it, the mineral is described as poikiloblastic. This observation can help interpret deformation history.
A rock which has many porphyroblasts is described as having a porphyroblastic texture.
As porphyroblasts grow, the foliation may be preserved as oriented inclusions trapped by the porphyroblast as it overgrows them, and this is helpful for tracking changing deformation planes.
In metamorphic rocks that experience deformation during metamorphism, porphyroblasts may grow before, during, or after the phase of deformation recorded by the matrix minerals. The relationship of porphyroblast growth to deformation is typically evaluated by comparing the shape orientation of trails of mineral inclusions in the porphyroblast to the matrix fabric.
Some garnet porp
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https://en.wikipedia.org/wiki/Artificial%20wave
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Artificial waves are human-made waves usually created on a specially designed surface or in a pool.
Making waves
Surface waves can be created by any moving object displacing fluid: turbine blades, paddles, a hand, a flung stone, etc. Each pulse of water (or crest) pushed outward from the disturbance leaves a space (or trough) behind it which causes another, smaller pulse to follow: thus a thrown stone's single impact causes a series of ripples. Larger waves can be built up if a series of movements are timed to reinforce waves' motion, much like a person sliding back and forth in a bathtub. Boundaries and obstacles also shape waves by concentrating or dissipating some of the wave's energy.
When fluid flows over a surface which diverts it upward, this flow can rise above the rest of the fluid in a standing wave which remains in one place while the flow lasts. An example of a natural standing wave may be found in swift-flowing streams, downstream from a boulder in the stream bed.
Artificial reefs can also be placed into natural wave environments to enhance the quality of the incoming breaking wave for surfing. Wave focusing areas can build up wave power and height prior to breaking, and breaking surfaces then trip the wave up to make it break; the surfing surface then carries the breaking wave along an angle that maximises its value for surfing.
Applications
In a wave pool water is pushed out of an opening with enough force to create a wave-like shape. Riders can ride thi
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https://en.wikipedia.org/wiki/ADAMTS2
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A disintegrin and metalloproteinase with thrombospondin motifs 2 (ADAM-TS2) also known as procollagen I N-proteinase (PC I-NP) is an enzyme that in humans is encoded by the ADAMTS2 gene.
Gene
The ADAMTS2 gene is located on the long (q) arm of chromosome 5 at the end (terminus) of the arm, from base pair 178,473,473 to base pair 178,704,934.
Function
ADAMTS2 is responsible for processing several types of procollagen proteins. Procollagens are the precursors of collagens, the proteins that add strength and support to many body tissues. Specifically, this enzyme clips a short chain of amino acids off one end of the procollagen. This clipping step is necessary for collagen molecules to function normally and assemble into fibrils outside cells.
Clinical significance
Ehlers-Danlos syndrome, dermatosparaxis type is caused by mutations in the ADAMTS2 gene. Several mutations in the ADAMTS2 gene have been identified in people with this syndrome. These mutations greatly reduce the production of the enzyme made by the ADAMTS2 gene. Procollagen cannot be processed correctly without this enzyme. As a result, collagen fibrils are not assembled properly; they appear ribbon-like and disorganized under the microscope. Cross-links, or chemical interactions, between collagen fibrils are also affected. These defects weaken connective tissue (the tissue that binds and supports the body's muscles, ligaments, organs, and skin), which causes the signs and symptoms of the disorder.
See also
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https://en.wikipedia.org/wiki/Eigenvector%20centrality
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In graph theory, eigenvector centrality (also called eigencentrality or prestige score) is a measure of the influence of a node in a network. Relative scores are assigned to all nodes in the network based on the concept that connections to high-scoring nodes contribute more to the score of the node in question than equal connections to low-scoring nodes. A high eigenvector score means that a node is connected to many nodes who themselves have high scores.
Google's PageRank and the Katz centrality are variants of the eigenvector centrality.
Using the adjacency matrix to find eigenvector centrality
For a given graph with vertices let be the adjacency matrix, i.e. if vertex is linked to vertex , and otherwise. The relative centrality score, , of vertex can be defined as:
where is the set of neighbors of and is a constant. With a small rearrangement this can be rewritten in vector notation as the eigenvector equation
In general, there will be many different eigenvalues for which a non-zero eigenvector solution exists. However, the additional requirement that all the entries in the eigenvector be non-negative implies (by the Perron–Frobenius theorem) that only the greatest eigenvalue results in the desired centrality measure. The component of the related eigenvector then gives the relative centrality score of the vertex in the network. The eigenvector is only defined up to a common factor, so only the ratios of the centralities of the vertices are well def
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https://en.wikipedia.org/wiki/CHRD
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CHRD may refer to:
Chordin, Chordin, the gene for a human protein involved in embryonic development
CHRD-FM, Canadian radio station
Chinese Human Rights Defenders, a human rights activist group
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https://en.wikipedia.org/wiki/Sziklai%20pair
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In electronics, the Sziklai pair, also known as a complementary feedback pair, is a configuration of two bipolar transistors, similar to a Darlington pair. In contrast to the Darlington arrangement, the Sziklai pair has one NPN and one PNP transistor, and so it is sometimes also called the "complementary Darlington". The configuration is named for George C. Sziklai, thought to be its inventor.
Characteristics
The current gain of the Sziklai pair is similar to that of a Darlington pair and is the product of the current gains of the two transistors. Figure 1 shows an NPN-PNP pair that acts like a single NPN transistor overall. By replacing Q1 with a PNP transistor and Q2 with an NPN transistor the pair will act like a PNP transistor overall.
Applications
In a typical application the Sziklai pair acts somewhat like a single transistor with the same type (e.g., NPN) as Q1 but with a very high current gain (β). The emitter of Q2 functions as a collector. Hence the emitter of Q2 is labeled "C" in Figure 1. Likewise, in a typical application the collector of Q2 (also connected to the emitter of Q1) functions as an emitter and is thus labeled "E". As with a Darlington pair, a resistor (e.g., 100 Ω to 1 kΩ) can be connected between Q2's emitter and base to improve its turn-off time (i.e., improve its performance for high frequency signals).
Advantages
One advantage over the Darlington pair is that the base turn-on voltage is only about 0.6 V, or about half of the Darlington's 1.2
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https://en.wikipedia.org/wiki/Fan%20Zhiyi
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Fan Zhiyi (; born 6 November 1969) is a Chinese coach and former international footballer. He played as a defender for Shanghai Shenhua, Crystal Palace, Dundee, Shanghai COSCO Huili, Cardiff City, Buler Rangers and Shanghai Zobon.
He was considered a trailblazer in his native homeland when Sun Jihai and he became the first two Chinese footballers to play in the English leagues, joining Crystal Palace in 1998. Internationally, he would go on to play with the Chinese national team in the 2002 FIFA World Cup. He has since gone on to become a football coach and had his first stint as manager at Shanghai East Asia.
Club career
Fan Zhiyi was considered a talented youngster and integrated into the Chinese National B Team which was allowed to take part in the Chinese football league system for a season. His time with them was extremely successful and he was even able to win the Chinese league title with the team in the 1989 league season before he had to return to Shanghai Shenhua. After returning to Shanghai and playing in his first season as a professional, Fan's best was brought out of him due to the improved level of play. His superb fitness and hardworking ethics as well as his excellent positional play as a central defender would see him become a regular within the team. By the 1995 league season, he had already gained a reputation as tough tackler who had superb aerial ability especially from set-piece plays, however he would also show his versatility as a player when he pl
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https://en.wikipedia.org/wiki/Rubber%20diode
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In electronics, a rubber diode or V multiplier is a bipolar junction transistor circuit that serves as a voltage reference. It consists of one transistor and two resistors, and the reference voltage across the circuit is determined by the selected resistor values and the base-to-emitter voltage (V) of the transistor. The circuit behaves as a voltage divider, but with the voltage across the base-emitter resistor determined by the forward base-emitter junction voltage.
It is commonly used in the biasing of push-pull output stages of amplifiers, where one benefit is thermal compensation: The temperature-dependent variations in the multiplier's V, approximately -2.2 mV/°C, can be made to match variations occurring in the V of the power transistors by mounting to the same heat sink. In this context, it is sometimes called a bias servo.
References
Semiconductors
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https://en.wikipedia.org/wiki/Disintegrin
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Disintegrins are a family of small proteins (45–84 amino acids in length) from viper venoms that function as potent inhibitors of both platelet aggregation and integrin-dependent cell adhesion.
Operation
Disintegrins work by countering the blood clotting steps, inhibiting the clumping of platelets. They interact with the beta-1 and -3 families of integrins receptors. Integrins are cell receptors involved in cell–cell and cell–extracellular matrix interactions, serving as the final common pathway leading to aggregation via formation of platelet–platelet bridges, which are essential in thrombosis and haemostasis. Disintegrins contain an RGD (Arg-Gly-Asp) or KGD (Lys-Gly-Asp) sequence motif that binds specifically to integrin IIb-IIIa receptors on the platelet surface, thereby blocking the binding of fibrinogen to the receptor–glycoprotein complex of activated platelets. Disintegrins act as receptor antagonists, inhibiting aggregation induced by ADP, thrombin, platelet-activating factor and collagen. The role of disintegrin in preventing blood coagulation renders it of medical interest, particularly with regard to its use as an anti-coagulant.
Types of disintegrin
Disintegrins from different snake species have been characterised: albolabrin, applagin, barbourin, batroxostatin, bitistatin, obtustatin, schistatin, echistatin, elegantin, eristicophin, flavoridin, halysin, kistrin, mojastin (Crotalus scutulatus), rubistatin (Crotalus ruber), tergeminin, salmosin, tzabcanin (Crotal
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https://en.wikipedia.org/wiki/State%20vector%20%28navigation%29
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In navigation, a state vector is a set of data describing exactly where an object is located in space, and how it is moving.
Mathematical representation
A state vector typically will contain seven elements: three position coordinates, three velocity terms, and the time at which these values were valid. Mathematically, in order to describe positions in a N-dimensional space () then a state vector belongs to :
or simply
where is the position vector and is the velocity vector.
Since there is freedom to choose coordinate systems for position, a state vector may also be expressed in a variety of coordinate systems (e.g. the North east down coordinate system).
See also
Orbital state vectors
Navigation
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https://en.wikipedia.org/wiki/Introduction%20to%20Algorithms
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Introduction to Algorithms is a book on computer programming by Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest, and Clifford Stein. The book has been widely used as the textbook for algorithms courses at many universities and is commonly cited as a reference for algorithms in published papers, with over 10,000 citations documented on CiteSeerX. The book sold half a million copies during its first 20 years. Its fame has led to the common use of the abbreviation "CLRS" (Cormen, Leiserson, Rivest, Stein), or, in the first edition, "CLR" (Cormen, Leiserson, Rivest).
In the preface, the authors write about how the book was written to be comprehensive and useful in both teaching and professional environments. Each chapter focuses on an algorithm, and discusses its design techniques and areas of application. Instead of using a specific programming language, the algorithms are written in pseudocode. The descriptions focus on the aspects of the algorithm itself, its mathematical properties, and emphasize efficiency.
Editions
The first edition of the textbook did not include Stein as an author, and thus the book became known by the initialism CLR. It included two chapters ("Arithmetic Circuits" & "Algorithms for Parallel Computers") that were dropped in the second edition. After the addition of the fourth author in the second edition, many began to refer to the book as "CLRS". This first edition of the book was also known as "The Big White Book (of Algorithms)." With the
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https://en.wikipedia.org/wiki/AD%20Leonis
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AD Leonis (Gliese 388) is a red dwarf star. It is located relatively near the Sun, at a distance of , in the constellation Leo. AD Leonis is a main sequence star with a spectral classification of M3.5V. It is a flare star that undergoes random increases in luminosity.
Properties
AD Leonis is an M-type star with a spectral type M3.5eV, indicating it is a main sequence star that displays emission lines in its spectrum. At a trigonometric distance of , it has an apparent visual magnitude of 9.43. It has about 39–42% of the Sun's mass — above the mass at which a star is fully convective — and 39% of the Sun's radius. The projected rotation of this star is only 2.4 km/s, but it completes a rotation once every 2.227 days, indicating a relatively pole-on inclination of about . It is a relatively young star with an estimated age of 25–300 million years, and is considered a member of the young disk population.
The variable nature of this star was first observed in 1949 by Katherine C. Gordon and Gerald E. Kron at Lick Observatory. AD Leonis is one of the most active flare stars known, and the emissions from the flares have been detected across the electromagnetic spectrum as high as the X-ray band. The net magnetic flux at the surface is about 3 kG. Besides star spots, about 73% of the surface is covered by magnetically active regions. Examination of the corona in X-ray shows compact loop structures that span up to 30% of the size of the star. The average temperature of the corona i
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https://en.wikipedia.org/wiki/Chinese%20wax
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Chinese wax is a white to yellowish-white, gelatinous, crystalline water-insoluble substance obtained from the wax secreted by certain insects.
It resembles spermaceti but is harder, more friable, and with a higher melting point. Two scale insects produce the wax: Ceroplastes ceriferus, common in China and India, and the related Ericerus pela, found in China and Japan. These insects deposit their secretions on the branches of certain species of Ligustrum (privet) tree. The insects and their secretions are harvested and boiled with water to extract the raw wax. The insect bodies, which settle to the bottom, are used as food for swine.
According to an article in a November 1932 magazine article in the journal Nature by Herbert Beardsley, "...the male larvae of a white insect, about the size of a mosquito, built a cocoon of pure, shining wax. The tree that produces the white wax insect grows in the Chien-Chang Valley, and there, about march, one may see, on the limbs and branches, round, brown forms, which contain innumerable white insects. If they are allowed to remain where they are, they will eventually drop off in a dead mass, for the food is not right for them; but if they are transported to other kinds of plants, the females will lay their eggs, the larvae will thrive and the male larvae will construct their shining palaces, which yield a profit to the wax-farmers. So, late in March, the insects are tied up in a leaf of the wood oil tree, then placed in gourd like rec
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https://en.wikipedia.org/wiki/Dennis%20Lindley
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Dennis Victor Lindley (25 July 1923 – 14 December 2013) was an English statistician, decision theorist and leading advocate of Bayesian statistics.
Biography
Lindley grew up in the south-west London suburb of Surbiton. He was an only child and his father was a local building contractor. Lindley recalled (to Adrian Smith) that the family had "little culture" and that both his parents were "proud of the fact that they had never read a book." The school Lindley attended, Tiffin School, introduced him to "ordinary cultural activities." From there Lindley went to read mathematics at Trinity College, Cambridge in 1941. During the war the degree course lasted only two years and, on finishing, Lindley had a choice between entering the armed forces and joining the Civil Service as a statistician. He chose the latter and, after taking a short course given by Oscar Irwin which he "did not understand", he joined a section of the Ministry of Supply doing statistical work under George Barnard.
After the war Lindley spent some time at the National Physical Laboratory before returning to Cambridge for a further year of study. From 1948 to 1960 he worked at Cambridge, starting as a demonstrator and leaving as director of the Statistical Laboratory. In 1960 Lindley left to take up a new chair at Aberystwyth. In 1967 he moved to University College London. In 1977 Lindley took early retirement at the age of 54. From then until 1987 he travelled the world as an "itinerant scholar", and later co
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https://en.wikipedia.org/wiki/T2B
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T2B may refer to:
t2B, code for a version of the Scion xB
T2B, a temperature classification, also referred to as a T-code, on electrical equipment labeled for hazardous locations
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https://en.wikipedia.org/wiki/Collagen%2C%20type%20I%2C%20alpha%201
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Collagen, type I, alpha 1, also known as alpha-1 type I collagen, is a protein that in humans is encoded by the gene. COL1A1 encodes the major component of type I collagen, the fibrillar collagen found in most connective tissues, including cartilage.
Function
Collagen is a protein that strengthens and supports many tissues in the body, including cartilage, bone, tendon, skin and the white part of the eye (sclera). The gene produces a component of type I collagen, called the pro-alpha1(I) chain. This chain combines with another pro-alpha1(I) chain and also with a pro-alpha2(I) chain (produced by the gene) to make a molecule of type I procollagen. These triple-stranded, rope-like procollagen molecules must be processed by enzymes outside the cell. Once these molecules are processed, they arrange themselves into long, thin fibrils that cross-link to one another in the spaces around cells. The cross-links result in the formation of very strong mature type I collagen fibers.
Collagenous function includes rigidity and elasticity.
Gene
The gene is located on the long (q) arm of chromosome 17 between positions 21.3 and 22.1, from base pair to base pair .
Clinical significance
Mutations in the gene are associated with the following conditions:
Ehlers–Danlos syndrome, vascular type: In rare cases, specific heterozygous arginine-to-cysteine substitution mutations in COL1A1 that are also associated with vascular fragility and mimic COL3A1-vEDS
Ehlers–Danlos syndrome, ar
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https://en.wikipedia.org/wiki/Boe-Bot
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BOE–Bot is short for Board of Education robot. It is the trade name of a robot kit that is used in junior high, high school and college robotics classes. It consists of a main circuit board (the Board of Education) and breadboard, a plug–in BASIC Stamp microcontroller, two servo motors to drive the wheels, and an aluminum chassis that the parts bolt onto. Students can use Erector set parts, Lego blocks, and additional servos to build custom projects. The BOE-bot has been manufactured and sold by Parallax Inc since 1998.
Main components
The green detachable main circuit, mounted on the top of the robot is called the Board of Education. The microcontroller which plugs into a socket on the green circuit board is called the BASIC Stamp . The BASIC Stamp is programmed in PBASIC. The rear wheel is a drilled polyethylene ball held in place with a cotter pin. Wheels are machined to fit on the servo spline and held in place with a screw. The BASIC Stamp is easy to program. The Boe–Bot is small, approximately four inches wide, and runs on four AA batteries. There is no soldering required for construction.
Features
The Boe–Bot is a robot that can be used in a variety of ways including combining Microsoft Robotics Developer Studio software with the Boe–Bot to control the robot's movements. The BOE–Bot is programmed using the PBASIC language.
References
External links
Parallax homepage
Official Boe–Bot information page
Parallax, Inc. products
Entertainment robots
Robot kits
Rolling
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https://en.wikipedia.org/wiki/Differential%20entropy
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Differential entropy (also referred to as continuous entropy) is a concept in information theory that began as an attempt by Claude Shannon to extend the idea of (Shannon) entropy, a measure of average (surprisal) of a random variable, to continuous probability distributions. Unfortunately, Shannon did not derive this formula, and rather just assumed it was the correct continuous analogue of discrete entropy, but it is not. The actual continuous version of discrete entropy is the limiting density of discrete points (LDDP). Differential entropy (described here) is commonly encountered in the literature, but it is a limiting case of the LDDP, and one that loses its fundamental association with discrete entropy.
In terms of measure theory, the differential entropy of a probability measure is the negative relative entropy from that measure to the Lebesgue measure, where the latter is treated as if it were a probability measure, despite being unnormalized.
Definition
Let be a random variable with a probability density function whose support is a set . The differential entropy or is defined as
For probability distributions which do not have an explicit density function expression, but have an explicit quantile function expression, , then can be defined in terms of the derivative of i.e. the quantile density function as
.
As with its discrete analog, the units of differential entropy depend on the base of the logarithm, which is usually 2 (i.e., the units are bits). See
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https://en.wikipedia.org/wiki/Oxygenase
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An oxygenase is any enzyme that oxidizes a substrate by transferring the oxygen from molecular oxygen O2 (as in air) to it. The oxygenases form a class of oxidoreductases; their EC number is EC 1.13 or EC 1.14.
Structure
Most oxygenases contain either a metal, usually iron, or an organic cofactor, usually flavin. These cofactors interact with O2, leading to its transfer to substrate.
Oxygenases constitute a major intracellular source of iron and carbon monoxide
Mechanism
Two types of oxygenases are recognized:
Monooxygenases, or mixed function oxidase, transfer one oxygen atom to the substrate, and reduce the other oxygen atom to water.
Dioxygenases, or oxygen transferases, incorporate both atoms of molecular oxygen (O2) into the product(s) of the reaction.
Among the most common monooxygenases are the cytochrome P450 oxidases, responsible for breaking down numerous chemicals in the body.
History
Oxygenases were discovered in 1955 simultaneously by two groups, Osamu Hayaishi from Japan and Howard S. Mason from the US. Hayaishi was awarded the 1986 Wolf Prize in Medicine "for the discovery of the oxygenase enzymes and elucidation of their structure and biological importance."
References
Enzymes
Oxygenases
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https://en.wikipedia.org/wiki/Wax%20acid
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The wax acids are a subgroup of saturated unbranched alkanoic acids. The frontier between fatty acids and wax acids is fluid. It often begins at 22 carbon atoms.
The members are:
Behenic acid C-22
Lignoceric acid C-24
Cerotic acid C-26
Montanic acid C-28
Melissic acid C-30
Lacceroic acid C-32
Geddic acid C-34
Alkanoic acids
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https://en.wikipedia.org/wiki/Cost%20efficiency
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Cost efficiency (or cost optimality), in the context of parallel computer algorithms, refers to a measure of how effectively parallel computing can be used to solve a particular problem. A parallel algorithm is considered cost efficient if its asymptotic running time multiplied by the number of processing units involved in the computation is comparable to the running time of the best sequential algorithm.
For example, an algorithm that can be solved in time using the best known sequential algorithm and in a parallel computer with processors will be considered cost efficient.
Cost efficiency also has applications to human services.
References
Advanced Computer Architectures: A Design Space Approach, D. Sima, T. Fountain and P. Kacsuk, Addison-Wesley, 1997.
Parallel computing
es:análisis de coste-beneficio
sv:Kostnads-effekt-analys
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https://en.wikipedia.org/wiki/Caesium%20lithium%20borate
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Caesium lithium borate or cesium lithium borate (CsLiB6O10), also known as CLBO, is a non-linear crystal for ultraviolet applications and generates the fourth and fifth harmonics of the Nd:YAG fundamental laser wavelength (1064 nm).
Nonlinear optical properties of CLBO
References
.
.
Further reading
.
.
External links
Non-linear Crystal Cesium Lithium Borate (CsLiB6O10 or CLBO) from MolTech GmbH
Caesium compounds
Lithium compounds
Borates
Nonlinear optical materials
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https://en.wikipedia.org/wiki/Crystal%20Cascades
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The Crystal Cascades is a cascade waterfall on the Freshwater Creek in the Far North region of Queensland, Australia.
Location and features
The Crystal Cascades is located in a relatively unspoilt section of the upper Freshwater Creek, in the Redlynch Valley, west of Cairns, with numerous waterfalls and swimming waterholes popular with locals and tourists. The largest waterhole is sited alongside a sheer cliff which locals and tourists climb to jump into the adjoining deep waterhole. The most famous part of the cliff is called "No Fear" which is the highest perch from which to jump. In 2014 an 18yearold man drowned when he failed to resurface after slipping over the edge of the waterfall, while swimming in a restricted area.
See also
List of waterfalls of Queensland
References
External links
Cairns Attractions Website
Waterfalls of Far North Queensland
Cascade waterfalls
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https://en.wikipedia.org/wiki/Upper-convected%20time%20derivative
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In continuum mechanics, including fluid dynamics, an upper-convected time derivative or Oldroyd derivative, named after James G. Oldroyd, is the rate of change of some tensor property of a small parcel of fluid that is written in the coordinate system rotating and stretching with the fluid.
The operator is specified by the following formula:
where:
is the upper-convected time derivative of a tensor field
is the substantive derivative
is the tensor of velocity derivatives for the fluid.
The formula can be rewritten as:
By definition, the upper-convected time derivative of the Finger tensor is always zero.
It can be shown that the upper-convected time derivative of a spacelike vector field is just its Lie derivative by the velocity field of the continuum.
The upper-convected derivative is widely used in polymer rheology for the description of the behavior of a viscoelastic fluid under large deformations.
Examples for the symmetric tensor A
Simple shear
For the case of simple shear:
Thus,
Uniaxial extension of incompressible fluid
In this case a material is stretched in the direction X and compresses in the directions Y and Z, so to keep volume constant.
The gradients of velocity are:
Thus,
See also
Upper-convected Maxwell model
References
Notes
Multivariable calculus
Fluid dynamics
Non-Newtonian fluids
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https://en.wikipedia.org/wiki/Motive%20power
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Motive power may refer to:
In thermodynamics, natural agents such as water or steam, wind or electricity, that do work
In mechanics, the mechanical energy associated with the motion and position of an object
In physics, a synonym for power
In mechanical engineering, the source of mechanical power of a propulsion system
It may also refer to:
Motive power, a colloquial term for a railway locomotive
Motive Power, an Australian railway magazine
Motive power depot, a railway running shed
Electric Motive Power, an English electric car
MotivePower, a subsidiary of Wabtec
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https://en.wikipedia.org/wiki/Solar%20panel
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A solar panel is a device that converts sunlight into electricity by using photovoltaic (PV) cells. PV cells are made of materials that generate electrons when exposed to light. The electrons flow through a circuit and produce direct current (DC) electricity, which can be used to power various devices or be stored in batteries. Solar panels are also known as solar cell panels, solar electric panels, or PV modules.
Solar panels are usually arranged in groups called arrays or systems. A photovoltaic system consists of one or more solar panels, an inverter that converts DC electricity to alternating current (AC) electricity, and sometimes other components such as controllers, meters, and trackers. A photovoltaic system can be used to provide electricity for off-grid applications, such as remote homes or cabins, or to feed electricity into the grid and earn credits or payments from the utility company. This is called a grid-connected photovoltaic system.
Some advantages of solar panels are that they use a renewable and clean source of energy, reduce greenhouse gas emissions, and lower electricity bills. Some disadvantages are that they depend on the availability and intensity of sunlight, require cleaning, and have high initial costs. Solar panels are widely used for residential, commercial, and industrial purposes, as well as for space and transportation applications.
History
In 1839, the ability of some materials to create an electrical charge from light exposure was first
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https://en.wikipedia.org/wiki/Available%20for%20sale
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Available for sale (AFS) is an accounting term used to classify financial assets. AFS is one of the three general classifications, along with held for trading and held to maturity, under U.S. Generally Accepted Accounting Principles (US GAAP), specifically FAS 115. The IFRS also includes a fourth classification: loans and receivables.
US GAAP Treatment
Under US GAAP, AFS assets represent debt securities and other financial investments that are non-strategic, that are neither held for trading, nor held to maturity, nor held for strategic reasons, and that have a readily available market price. As such, the gains and losses resulting from marking AFS investments to market (revaluing them to market price / fair value each period) are not included in Net Income (unlike the gains and losses associated with "trading" investments) but are reflected in Other Comprehensive Income (income statement / retained earnings) and Accumulated Other Comprehensive Income (balance sheet) until they are realized (sold).
IFRS Treatment
Under IFRS, AFS assets are defined as being all financial assets that do not fall into one of the other classifications. As such, the treatment closely follows that of US GAAP. Gains or losses from revaluation of the asset are put through Other Comprehensive Income in Shareholders' Equity, except to the extent that any losses are assessed as being permanent and the asset is therefore impaired (under IAS 39, paragraph 58), or if the asset is sold or otherwise disp
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https://en.wikipedia.org/wiki/Ostwald%20ripening
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Ostwald ripening is a phenomenon observed in solid solutions and liquid sols that involves the change of an inhomogeneous structure over time, in that small crystals or sol particles first dissolve and then redeposit onto larger crystals or sol particles.
Dissolution of small crystals or sol particles and the redeposition of the dissolved species on the surfaces of larger crystals or sol particles was first described by Wilhelm Ostwald in 1896. For colloidal systems, Ostwald ripening is also found in water-in-oil emulsions, while flocculation is found in oil-in-water emulsions.
Mechanism
This thermodynamically-driven spontaneous process occurs because larger particles are more energetically favored than smaller particles. This stems from the fact that molecules on the surface of a particle are energetically less stable than the ones in the interior.
Consider a cubic crystal of atoms: all the atoms inside are bonded to 6 neighbours and are quite stable, but atoms on the surface are only bonded to 5 neighbors or fewer, which makes these surface atoms less stable. Large particles are more energetically favorable since, continuing with this example, more atoms are bonded to 6 neighbors and fewer atoms are at the unfavorable surface. As the system tries to lower its overall energy, molecules on the surface of a small particle (energetically unfavorable, with only 3 or 4 or 5 bonded neighbors) will tend to detach from the particle and diffuse into the solution.
Kelvin's equa
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https://en.wikipedia.org/wiki/Vector%20graphics%20%28disambiguation%29
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Vector graphics are a form of computer graphics.
Vector graphic may also refer to:
Vector Graphic, a computer company
Vektor Grafix, UK based computer game development company
See also
Raster graphics
Vector (disambiguation)
Vectorization (disambiguation)
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https://en.wikipedia.org/wiki/MEFV
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MEFV (Mediterranean fever) is a human gene that provides instructions for making a protein called pyrin (also known as marenostrin). Pyrin is produced in certain white blood cells (neutrophils, eosinophils and monocytes) that play a role in inflammation and in fighting infection. Inside these white blood cells, pyrin is found with the cytoskeleton, the structural framework that helps to define the shape, size, and movement of a cell. Pyrin's protein structure also allows it to interact with other molecules involved in fighting infection and in the inflammatory response.
Although pyrin's function is not fully understood, it likely assists in keeping the inflammation process under control. Research indicates that pyrin helps regulate inflammation by interacting with the cytoskeleton. Pyrin may direct the migration of white blood cells to sites of inflammation and stop or slow the inflammatory response when it is no longer needed.
The MEFV gene is located on the short (p) arm of chromosome 16 at position 13.3, from base pair 3,292,027 to 3,306,626.
Related conditions
More than 80 MEFV mutations that cause familial Mediterranean fever have been identified. A few mutations delete small amounts of DNA from the MEFV gene, which can lead to an abnormally small protein. Most MEFV mutations, however, change one of the protein building blocks (amino acids) used to make pyrin. The most common mutation replaces the amino acid methionine with the amino acid valine at protein position 69
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https://en.wikipedia.org/wiki/Crystal%20Mountains%20National%20Park
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Crystal Mountains National Park () is a twin park and one of the 13 national parks of Gabon. It is situated in the Monts de Crystal on the western edge of the Woleu-Ntem Plateau, between Equatorial Guinea and the Ogooué River. The twin parks, Mbe National Park and Mt Sene National Park, were established on 4 September 2002, based on their exceptionally high plant biodiversity and forming part of a former Pleistocene rain forest refugium.
The park is home to many animal species such as elephants or monkeys, and hundreds of species of butterflies can be found here, some of which are very rare, such as euphaedra brevis, cymothoe or graphium angrier.
External links
Wildlife Conservation Society
Virtual Tour of the National Parks
References
National parks of Gabon
Protected areas established in 2002
2002 establishments in Gabon
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https://en.wikipedia.org/wiki/Sequential%20analysis
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In statistics, sequential analysis or sequential hypothesis testing is statistical analysis where the sample size is not fixed in advance. Instead data are evaluated as they are collected, and further sampling is stopped in accordance with a pre-defined stopping rule as soon as significant results are observed. Thus a conclusion may sometimes be reached at a much earlier stage than would be possible with more classical hypothesis testing or estimation, at consequently lower financial and/or human cost.
History
The method of sequential analysis is first attributed to Abraham Wald with Jacob Wolfowitz, W. Allen Wallis, and Milton Friedman while at Columbia University's Statistical Research Group as a tool for more efficient industrial quality control during World War II. Its value to the war effort was immediately recognised, and led to its receiving a "restricted" classification. At the same time, George Barnard led a group working on optimal stopping in Great Britain. Another early contribution to the method was made by K.J. Arrow with D. Blackwell and M.A. Girshick.
A similar approach was independently developed from first principles at about the same time by Alan Turing, as part of the Banburismus technique used at Bletchley Park, to test hypotheses about whether different messages coded by German Enigma machines should be connected and analysed together. This work remained secret until the early 1980s.
Peter Armitage introduced the use of sequential analysis in me
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https://en.wikipedia.org/wiki/Mohite
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Mohite is a copper tin sulfide mineral with the chemical formula Cu2SnS3. It is colored greenish gray and leaves a gray streak. It is opaque and has metallic luster. Its crystal system is triclinic pedial. It is rated 4 on the Mohs Scale and has a specific gravity of 4.86.
Discovery and occurrence
Mohite was first described in 1982 for an occurrence in the Chatkal-Kuramin Mountains of eastern Uzbekistan. It was named after Günter Harald Moh (1929–1993), University of Heidelberg. It is of hydrothermal origin and occurs associated with tetrahedrite, famatinite, kuramite, mawsonite and emplectite in the type locality in Uzbekistan. It has also been reported from Salamanca Province, Spain; the Organullo Mining District of Salta Province, Argentina; and the Delamar Mountains of Lincoln County, Nevada, US.
References
Copper minerals
Tin minerals
Sulfide minerals
Monoclinic minerals
Minerals in space group 9
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https://en.wikipedia.org/wiki/Centrosymmetry
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In crystallography, a centrosymmetric point group contains an inversion center as one of its symmetry elements. In such a point group, for every point (x, y, z) in the unit cell there is an indistinguishable point (-x, -y, -z). Such point groups are also said to have inversion symmetry. Point reflection is a similar term used in geometry.
Crystals with an inversion center cannot display certain properties, such as the piezoelectric effect.
The following space groups have inversion symmetry: the triclinic space group 2, the monoclinic 10-15, the orthorhombic 47-74, the tetragonal 83-88 and 123-142, the trigonal 147, 148 and 162-167, the hexagonal 175, 176 and 191-194, the cubic 200-206 and 221-230.
Point groups lacking an inversion center (non-centrosymmetric) can be polar, chiral, both, or neither.
A polar point group is one whose symmetry operations leave more than one common point unmoved. A polar point group has no unique origin because each of those unmoved points can be chosen as one. One or more unique polar axes could be made through two such collinear unmoved points. Polar crystallographic point groups include 1, 2, 3, 4, 6, m, mm2, 3m, 4mm, and 6mm.
A chiral (often also called enantiomorphic) point group is one containing only proper (often called "pure") rotation symmetry. No inversion, reflection, roto-inversion or roto-reflection (i.e., improper rotation) symmetry exists in such point group. Chiral crystallographic point groups include 1, 2, 3, 4, 6, 222, 42
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https://en.wikipedia.org/wiki/Reduced%20gradient%20bubble%20model
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The reduced gradient bubble model (RGBM) is an algorithm developed by Bruce Wienke for calculating decompression stops needed for a particular dive profile. It is related to the Varying Permeability Model. but is conceptually different in that it rejects the gel-bubble model of the varying permeability model.
It is used in several dive computers, particularly those made by Suunto, Aqwary, Mares, HydroSpace Engineering, and Underwater Technologies Center. It is characterised by the following assumptions: blood flow (perfusion) provides a limit for tissue gas penetration by diffusion; an exponential distribution of sizes of bubble seeds is always present, with many more small seeds than large ones; bubbles are permeable to gas transfer across surface boundaries under all pressures; the haldanean tissue compartments range in half time from 1 to 720 minutes, depending on gas mixture.
Some manufacturers such as Suunto have devised approximations of Wienke's model. Suunto uses a modified haldanean nine-compartment model with the assumption of reduced off-gassing caused by bubbles. This implementation offers both a depth ceiling and a depth floor for the decompression stops. The former maximises tissue off-gassing and the latter minimises bubble growth. The model has been correlated and validated in a number of published articles using collected dive profile data.
Description
The model is based on the assumption that phase separation during decompression is random, yet highly
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https://en.wikipedia.org/wiki/Jim%20Kent
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William James Kent (born February 10, 1960) is an American research scientist and computer programmer. He has been a contributor to genome database projects and the 2003 winner of the Benjamin Franklin Award.
Early life
Kent was born in Hawaii and grew up in San Francisco, California, United States.
Computer animation
Kent began his programming career in 1983 with Island Graphics Inc. where he wrote the Aegis Animator program for the Amiga home computer. This program combined polygon tweening in 3D with simple 2D cel-based animation. In 1985 he founded and ran a software company, Dancing Flame, which adapted the Aegis Animator to the Atari ST, and created Cyber Paint for that machine. Cyber Paint was a 2D animation program that brought together a wide variety of animation and paint functionality and the delta-compressed animation format developed for CAD-3D. The user could move freely between animation frames and paint arbitrarily, or utilize various animation tools for automatic tweening movement across frames. Cyber Paint was one of the first, if not the first, consumer program that enabled the user to paint across time in a compressed digital video format. Later he developed a similar program, the Autodesk Animator for PC compatibles, where the image compression improved to the point it could play off of hard disk, and one could paint using "inks" that performed algorithmic transformations such as smoothing, transparency, and tiled patterns. The Autodesk Animator was
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https://en.wikipedia.org/wiki/CXAM%20radar
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The CXAM radar system was the first production radar system deployed on United States Navy ships, operating in the mid-high VHF frequency band of 200 MHz. It followed several earlier prototype systems, such as the NRL radar installed in April 1937 on the destroyer ; its successor, the XAF, installed in December 1938 on the battleship ; and the first RCA-designed system, the CXZ, installed in December 1938 or January 1939 on the battleship . Based on testing in January 1939, where the XAF was more reliable, the US Navy ordered RCA to build six XAF-based units for deployment and then shortly thereafter ordered 14 more.
The first six units RCA produced (delivered in 1940) were denoted "CXAM" and were a fusion of XAF and CXZ technologies. These were installed on the battleship , the aircraft carrier (in September 1940), and the heavy cruisers , , , and . The next 14 units RCA produced (also delivered in 1940) were denoted "CXAM-1" and were slight improvements over the CXAM design. These were installed on the battleships Texas (in October 1941), , , , and ; on the aircraft carriers , , , , and ; on the heavy cruiser ; on two light cruisers; and on the seaplane tender .
Radar detection range of aircraft depends on altitude, size, and number of the target aircraft, as well as the radar's characteristics, such as transmitter power and receiver sensitivity. Surface ships are more difficult to detect due to a number of factors such as signal return from waves (called in general gro
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https://en.wikipedia.org/wiki/Angiogenin
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Angiogenin (ANG) also known as ribonuclease 5 is a small 123 amino acid protein that in humans is encoded by the ANG gene. Angiogenin is a potent stimulator of new blood vessels through the process of angiogenesis. Ang hydrolyzes cellular RNA, resulting in modulated levels of protein synthesis and interacts with DNA causing a promoter-like increase in the expression of rRNA. Ang is associated with cancer and neurological disease through angiogenesis and through activating gene expression that suppresses apoptosis.
Function
Angiogenin is a key protein implicated in angiogenesis in normal and tumor growth. Angiogenin interacts with endothelial and smooth muscle cells resulting in cell migration, invasion, proliferation and formation of tubular structures. Ang binds to actin of both smooth muscle and endothelial cells to form complexes that activate proteolytic cascades which upregulate the production of proteases and plasmin that degrade the laminin and fibronectin layers of the basement membrane. Degradation of the basement membrane and extracellular matrix allows the endothelial cells to penetrate and migrate into the perivascular tissue. Signal transduction pathways activated by Ang interactions at the cellular membrane of endothelial cells produce extracellular signal-related kinase1/2 (ERK1/2) and protein kinase B/Akt. Activation of these proteins leads to invasion of the basement membrane and cell proliferation associated with further angiogenesis. The most important s
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https://en.wikipedia.org/wiki/Point-contact%20transistor
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The point-contact transistor was the first type of transistor to be successfully demonstrated. It was developed by research scientists John Bardeen and Walter Brattain at Bell Laboratories in December 1947. They worked in a group led by physicist William Shockley. The group had been working together on experiments and theories of electric field effects in solid state materials, with the aim of replacing vacuum tubes with a smaller device that consumed less power.
The critical experiment, carried out on December 16, 1947, consisted of a block of germanium, a semiconductor, with two very closely spaced gold contacts held against it by a spring. Brattain attached a small strip of gold foil over the point of a plastic triangle—a configuration which is essentially a point-contact diode. He then carefully sliced through the gold at the tip of the triangle. This produced two electrically isolated gold contacts very close to each other.
The piece of germanium used a surface layer with an excess of electrons. When an electric signal traveled in through the gold foil, it injected electron holes (points which lack electrons). This created a thin layer which had a scarcity of electrons.
A small positive current applied to one of the two contacts had an influence on the current which flowed between the other contact and the base upon which the block of germanium was mounted. In fact, a small change in the first contact current caused a greater change in the second contact current; thus
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https://en.wikipedia.org/wiki/Phase-type%20distribution
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A phase-type distribution is a probability distribution constructed by a convolution or mixture of exponential distributions. It results from a system of one or more inter-related Poisson processes occurring in sequence, or phases. The sequence in which each of the phases occurs may itself be a stochastic process. The distribution can be represented by a random variable describing the time until absorption of a Markov process with one absorbing state. Each of the states of the Markov process represents one of the phases.
It has a discrete-time equivalent the discrete phase-type distribution.
The set of phase-type distributions is dense in the field of all positive-valued distributions, that is, it can be used to approximate any positive-valued distribution.
Definition
Consider a continuous-time Markov process with m + 1 states, where m ≥ 1, such that the states 1,...,m are transient states and state 0 is an absorbing state. Further, let the process have an initial probability of starting in any of the m + 1 phases given by the probability vector (α0,α) where α0 is a scalar and α is a 1 × m vector.
The continuous phase-type distribution is the distribution of time from the above process's starting until absorption in the absorbing state.
This process can be written in the form of a transition rate matrix,
where S is an m × m matrix and S0 = –S1. Here 1 represents an m × 1 column vector with every element being 1.
Characterization
The distribution of time X until the pro
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https://en.wikipedia.org/wiki/NTRUSign
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NTRUSign, also known as the NTRU Signature Algorithm, is an NTRU public-key cryptography digital signature algorithm based on the GGH signature scheme. The original version of NTRUSign was Polynomial Authentication and Signature Scheme (PASS), and was published at CrypTEC'99. The improved version of PASS was named as NTRUSign, and was presented at the rump session of Asiacrypt 2001 and published in peer-reviewed form at the RSA Conference 2003. The 2003 publication included parameter recommendations for 80-bit security. A subsequent 2005 publication revised the parameter recommendations for 80-bit security, presented parameters that gave claimed security levels of 112, 128, 160, 192 and 256 bits, and described an algorithm to derive parameter sets at any desired security level. NTRU Cryptosystems, Inc. have applied for a patent on the algorithm.
NTRUSign involves mapping a message to a random point in 2N-dimensional space, where N is one of the NTRUSign parameters, and solving the closest vector problem in a lattice closely related to the NTRUEncrypt lattice. NTRUSign is claimed to be faster than those algorithms at low security levels, and considerably faster at high security levels. However, analysis had shown that original scheme is insecure and would leak knowledge of private key.
A redesigned pqNTRUSign had been submitted to the NIST Post-Quantum Cryptography Standardization competition. It is based on "hash-and-sign" (contrasting Fiat–Shamir transformation) methodolog
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https://en.wikipedia.org/wiki/GGH%20signature%20scheme
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The Goldreich-Goldwasser-Halevi (GGH) signature scheme is a digital signature scheme proposed in 1995 and published in 1997, based on solving the closest vector problem (CVP) in a lattice. The signer demonstrates knowledge of a good basis for the lattice by using it to solve CVP on a point representing the message; the verifier uses a bad basis for the same lattice to verify that the signature under consideration is actually a lattice point and is sufficiently close to the message point.
The idea was not developed in detail in the original paper, which focussed more on the associated encryption algorithm.
GGH signatures form the basis for the NTRUSign signature algorithm.
and Oded Regev had cryptanalyzed (broken) the original GGH signature scheme in 2006.
Bibliography
Preliminary version in EUROCRYPT 2006.
External links
The webpage of the original paper
Digital signature schemes
Lattice-based cryptography
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https://en.wikipedia.org/wiki/Zinc%20telluride
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Zinc telluride is a binary chemical compound with the formula ZnTe. This solid is a semiconductor material with a direct band gap of 2.26 eV. It is usually a p-type semiconductor. Its crystal structure is cubic, like that for sphalerite and diamond.
Properties
ZnTe has the appearance of grey or brownish-red powder, or ruby-red crystals when refined by sublimation. Zinc telluride typically has a cubic (sphalerite, or "zincblende") crystal structure, but can be also prepared as rocksalt crystals or in hexagonal crystals (wurtzite structure). Irradiated by a strong optical beam burns in presence of oxygen. Its lattice constant is 0.6101 nm, allowing it to be grown with or on aluminium antimonide, gallium antimonide, indium arsenide, and lead selenide. With some lattice mismatch, it can also be grown on other substrates such as GaAs, and it can be grown in thin-film polycrystalline (or nanocrystalline) form on substrates such as glass, for example, in the manufacture of thin-film solar cells. In the wurtzite (hexagonal) crystal structure, it has lattice parameters a = 0.427 and c = 0.699 nm.
Applications
Optoelectronics
Zinc telluride can be easily doped, and for this reason it is one of the more common semiconducting materials used in optoelectronics. ZnTe is important for development of various semiconductor devices, including blue LEDs, laser diodes, solar cells, and components of microwave generators. It can be used for solar cells, for example, as a back-surface f
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https://en.wikipedia.org/wiki/Mercury%20zinc%20telluride
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Mercury zinc telluride (HgZnTe, MZT) is a telluride of mercury and zinc, an alloy of mercury telluride and zinc telluride. It is a narrow-gap semiconductor material.
Mercury zinc telluride is used in infrared detectors and arrays for infrared imaging and infrared astronomy.
Mercury zinc telluride has better chemical, thermal, and mechanical stability than mercury cadmium telluride. The bandgap of MZT is more sensitive to composition fluctuations than that of MCT, which may be an issue for reproducible device fabrication. MZT is less amenable than MCT to fabrication of complex heterostructures by molecular beam epitaxy.
See also
Cadmium zinc telluride
Mercury cadmium telluride
External links
National Pollutant Inventory - Mercury and compounds Fact Sheet
Mercury(II) compounds
Zinc compounds
Tellurides
II-VI semiconductors
Infrared sensor materials
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https://en.wikipedia.org/wiki/Lead%20selenide
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Lead selenide (PbSe), or lead(II) selenide, a selenide of lead, is a semiconductor material. It forms cubic crystals of the NaCl structure; it has a direct bandgap of 0.27 eV at room temperature. (Note that incorrectly identifies PbSe and other IV–VI semiconductors as indirect gap materials.) A grey solid, it is used for manufacture of infrared detectors for thermal imaging.
The mineral clausthalite is a naturally occurring lead selenide.
It may be formed by direct reaction between its constituent elements, lead and selenium.
Infrared detection
PbSe was one of the first materials found to be sensitive to the infrared radiation used for military applications. Early research works on the material as infrared detector were carried out during the 1930s and the first useful devices were processed by Germans, Americans and British during and just after World War II. Since then, PbSe has been commonly used as an infrared photodetector in multiple applications, from spectrometers for gas and flame detection to infrared fuzes for artillery ammunition or Passive Infrared Cueing systems (PICs).
As a sensitive material to the infrared radiation, PbSe has unique and outstanding characteristics: it can detect IR radiation of wavelengths from 1.5 to 5.2 μm (mid-wave infrared window, abbreviated MWIR – in some special conditions it is possible to extend its response beyond 6 μm), it has a high detectivity at room temperature (uncooled performance), and due to its quantum nature, it al
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https://en.wikipedia.org/wiki/FMR1
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FMR1 (Fragile X Messenger Ribonucleoprotein 1) is a human gene that codes for a protein called fragile X messenger ribonucleoprotein, or FMRP. This protein, most commonly found in the brain, is essential for normal cognitive development and female reproductive function. Mutations of this gene can lead to fragile X syndrome, intellectual disability, premature ovarian failure, autism, Parkinson's disease, developmental delays and other cognitive deficits. The FMR1 premutation is associated with a wide spectrum of clinical phenotypes that affect more than two million people worldwide.
Function
Synaptic plasticity
FMRP has a diverse array of functions throughout different areas of the neuron; however these functions have not been fully characterized. FMRP has been suggested to play roles in nucleocytoplasmic shuttling of mRNA, dendritic mRNA localization, and synaptic protein synthesis. Studies of Fragile X syndrome have significantly aided in the understanding of the functionality of FMRP through the observed effects of FMRP loss on neurons. A mouse model of Fragile X Messenger Ribonucleoprotein implicated the involvement of FMRP in synaptic plasticity. Synaptic plasticity requires the production of new proteins in response to activation of synaptic receptors. It is the production of proteins in response to stimulation which is hypothesized to allow for the permanent physical changes and altered synaptic connections that are linked with the processes of learning and memory.
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