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https://en.wikipedia.org/wiki/Multinomial%20probit | In statistics and econometrics, the multinomial probit model is a generalization of the probit model used when there are several possible categories that the dependent variable can fall into. As such, it is an alternative to the multinomial logit model as one method of multiclass classification. It is not to be confused with the multivariate probit model, which is used to model correlated binary outcomes for more than one independent variable.
General specification
It is assumed that we have a series of observations Yi, for i = 1...n, of the outcomes of multi-way choices from a categorical distribution of size m (there are m possible choices). Along with each observation Yi is a set of k observed values x1,i, ..., xk,i of explanatory variables (also known as independent variables, predictor variables, features, etc.). Some examples:
The observed outcomes might be "has disease A, has disease B, has disease C, has none of the diseases" for a set of rare diseases with similar symptoms, and the explanatory variables might be characteristics of the patients thought to be pertinent (sex, race, age, blood pressure, body-mass index, presence or absence of various symptoms, etc.).
The observed outcomes are the votes of people for a given party or candidate in a multi-way election, and the explanatory variables are the demographic characteristics of each person (e.g. sex, race, age, income, etc.).
The multinomial probit model is a statistical model that can be used to predict the likely outcome of an unobserved multi-way trial given the associated explanatory variables. In the process, the model attempts to explain the relative effect of differing explanatory variables on the different outcomes.
Formally, the outcomes Yi are described as being categorically-distributed data, where each outcome value h for observation i occurs with an unobserved probability pi,h that is specific to the observation i at hand because it is determined by the values of the explanatory var |
https://en.wikipedia.org/wiki/Primate%20reintroduction | Primate reintroduction is a form of species reintroduction and is the process by which captive or previously free-ranging primates are either translocated or rehabilitated and released into the wild. The goals of primate reintroduction efforts are typically to reestablish or reinforce wild populations, improve the welfare of reintroduced individuals, and/or restore ecosystems (i.e. seed distribution). Primate reintroduction is associated with primate rehabilitation which is a form of wildlife rehabilitation that provides care and treatment for individual primates that have been injured, orphaned or abandoned in preparation for reintroduction back into the wild. Rehabilitation and reintroduction together are a strategy to combat the widespread decline of primate biodiversity worldwide and keep primate species and their habitats safe from extinction. The rehabilitated primates are most frequently formerly captive monkeys confiscated or rescued from the illegal pet and bushmeat trades.
Causes for primate biodiversity decline
It is commonly accepted by scientists that we are living through the sixth mass extinction (Holocene extinction) with species decline occurring at the highest rate since the last mass extinction, primarily due to anthropogenic forces. As of 2017 approximately 60% of all primate species are considered threatened and over 75% of populations are in decline.
Climate change
Primate habitat is increasingly threatened by the wide ranging impacts of climate change, with significant land cover change and catastrophic weather events causing habitat loss, fragmentation and impacting food supply. It is predicted that primate habitats will experience climate warming that is 10% higher than the global mean and will be increasingly vulnerable to significant precipitation shifts and extreme weather events. Further predictions show that over the coming decades climate change will impact primate species both directly as temperature increases and indirectly throu |
https://en.wikipedia.org/wiki/Thraustochytrium%20mitochondrial%20code | The Thraustochytrium mitochondrial code (translation table 23) is a genetic code found in the mitochondria of the labyrinthulid protist Thraustochytrium aureum. The mitochondrial genome was sequenced by the Organelle Genome Megasequencing Program.
Code
Differences from the standard code
It is the similar to the bacterial code (translation table 11) but it contains an additional stop codon (TTA) and also has a different set of start codons.
Systematic range and comments
Mitochondria of Thraustochytrium aureum.
See also
List of genetic codes |
https://en.wikipedia.org/wiki/Wire%20wrap | Wire wrap is an electronic component assembly technique that was invented to wire telephone crossbar switches, and later adapted to construct electronic circuit boards. Electronic components mounted on an insulating board are interconnected by lengths of insulated wire run between their terminals, with the connections made by wrapping several turns of uninsulated sections of the wire around a component lead or a socket pin.
Wires can be wrapped by hand or by machine, and can be hand-modified afterwards. It was popular for large-scale manufacturing in the 1960s and early 1970s, and continues today to be used for short runs and prototypes. The method eliminates the design and fabrication of a printed circuit board. Wire wrapping is unusual among other prototyping technologies since it allows for complex assemblies to be produced by automated equipment, but then easily repaired or modified by hand.
Wire wrap construction can produce assemblies that are more reliable than printed circuits: connections are less prone to fail due to vibration or physical stresses on the base board, and the lack of solder eliminates soldering faults such as corrosion, cold joints and dry joints. The connections themselves are firmer and have lower electrical resistance due to cold welding of the wire to the terminal post at the corners.
Wire wrap was used for assembly of high frequency prototypes and small production runs, including gigahertz microwave circuits and supercomputers. It is unique among automated prototyping techniques in that wire lengths can be exactly controlled, and twisted pairs or magnetically shielded twisted quads can be routed together.
Wire wrap construction became popular around 1960 in circuit board manufacturing, and use has now sharply declined. Surface-mount technology has made the technique much less useful than in previous decades. Solder-less breadboards and the decreasing cost of professionally made PCBs have nearly eliminated this technology.
History |
https://en.wikipedia.org/wiki/Inverse%20iteration | In numerical analysis, inverse iteration (also known as the inverse power method) is an iterative eigenvalue algorithm. It allows one to find an approximate
eigenvector when an approximation to a corresponding eigenvalue is already known.
The method is conceptually similar to the power method.
It appears to have originally been developed to compute resonance frequencies in the field of structural mechanics.
The inverse power iteration algorithm starts with an approximation for the eigenvalue corresponding to the desired eigenvector and a vector , either a randomly selected vector or an approximation to the eigenvector. The method is described by the iteration
where are some constants usually chosen as Since eigenvectors are defined up to multiplication by constant, the choice of can be arbitrary in theory; practical aspects of the choice of are discussed below.
At every iteration, the vector is multiplied by the matrix and normalized.
It is exactly the same formula as in the power method, except replacing the matrix by
The closer the approximation to the eigenvalue is chosen, the faster the algorithm converges; however, incorrect choice of can lead to slow convergence or to the convergence to an eigenvector other than the one desired. In practice, the method is used when a good approximation for the eigenvalue is known, and hence one needs only few (quite often just one) iterations.
Theory and convergence
The basic idea of the power iteration is choosing an initial vector (either an eigenvector approximation or a random vector) and iteratively calculating . Except for a set of zero measure, for any initial vector, the result will converge to an eigenvector corresponding to the dominant eigenvalue.
The inverse iteration does the same for the matrix , so it converges to the eigenvector corresponding to the dominant eigenvalue of the matrix .
Eigenvalues of this matrix are where are eigenvalues of .
The largest of these numbers corresponds t |
https://en.wikipedia.org/wiki/Year%202038%20problem | The year 2038 problem (also known as Y2038, Y2K38, Y2K38 superbug or the Epochalypse) is a time formatting bug in computer systems with representing times after 03:14:07 UTC on 19 January 2038.
The problem exists in systems which measure Unix time – the number of seconds elapsed since the Unix epoch (00:00:00 UTC on 1 January 1970) – and store it in a signed 32-bit integer. The data type is only capable of representing integers between −(2) and 231 − 1, meaning the latest time that can be properly encoded is 2 − 1 seconds after epoch (03:14:07 UTC on 19 January 2038). Attempting to increment to the following second (03:14:08) will cause the integer to overflow, setting its value to −(2) which systems will interpret as 2 seconds before epoch (20:45:52 UTC on 13 December 1901). The problem is similar in nature to the year 2000 problem.
Computer systems that use time for critical computations may encounter fatal errors if the Y2038 problem is not addressed. Some applications that use future dates have already encountered the bug. The most vulnerable systems are those which are infrequently or never updated, such as legacy and embedded systems. There is no universal solution to the problem, though many modern systems have been upgraded to measure Unix time with signed 64-bit integers which will not overflow for 292 billion years—approximately 21 times the estimated age of the universe.
Cause
Many computer systems measure time and date as Unix time, an international standard for digital timekeeping. Unix time is defined as the number of seconds elapsed since 00:00:00 UTC on 1 January 1970 (an arbitrarily chosen time based on the creation of the first Unix system), which has been dubbed the Unix epoch.
Unix time has historically been encoded as a signed 32-bit integer, a data type composed of 32 binary digits (bits) which represent an integer value, with 'signed' meaning that the number is stored in Two's complement format. Thus, a signed 32-bit integer can only rep |
https://en.wikipedia.org/wiki/Citicoline | Citicoline (INN), also known as cytidine diphosphate-choline (CDP-Choline) or cytidine 5'-diphosphocholine is an intermediate in the generation of phosphatidylcholine from choline, a common biochemical process in cell membranes. Citicoline is naturally occurring in the cells of human and animal tissue, in particular the organs.
Use as a dietary supplement
Citicoline is available as a supplement in over 70 countries under a variety of brand names: CereBleu, Cebroton, Ceraxon, Cidilin, Citifar, Cognizin, Difosfocin, Hipercol, NeurAxon, Nicholin, Sinkron, Somazina, Synapsine, Startonyl, Trausan, Xerenoos, etc. When taken as a supplement, citicoline is hydrolyzed into choline and cytidine in the intestine. Once these cross the blood–brain barrier it is reformed into citicoline by the rate-limiting enzyme in phosphatidylcholine synthesis, CTP-phosphocholine cytidylyltransferase.
Research
Memory and cognition
Studies suggest, but have not confirmed, potential benefits of citicoline for cognitive impairments.
Ischemic stroke
Some preliminary research suggested that citicoline may reduce the rates of death and disability following an ischemic stroke.
However, the largest citicoline clinical trial to date (a randomised, placebo-controlled, sequential trial of 2,298 patients with moderate-to-severe acute ischaemic stroke in Europe), found no benefit of administering citicoline on survival or recovery from stroke. A meta-analysis of seven trials reported no statistically significant benefit for long-term survival or recovery.
Vision
The effect of citicoline on visual function has been studied in patients with glaucoma, with possible positive effect for protecting vision.
Mechanism of action
Neuroprotective effects
Citicoline may have neuroprotective effects due to its preservation of cardiolipin and sphingomyelin, preservation of arachidonic acid content of phosphatidylcholine and phosphatidylethanolamine, partial restoration of phosphatidylcholine levels, and stimula |
https://en.wikipedia.org/wiki/HBsAg | HBsAg (also known as the Australia antigen) is the surface antigen of the hepatitis B virus (HBV). Its presence in blood indicates current hepatitis B infection.
Structure and function
The viral envelope of an enveloped virus has different surface proteins from the rest of the virus which act as antigens. These antigens are recognized by antibody proteins that bind specifically to one of these surface proteins.
Immunoassay
Today, these antigen-proteins can be genetically manufactured (e.g. transgene E. coli) to produce material for a simple antigen test, which detects the presence of HBV.
It is present in the sera of patients with viral hepatitis B (with or without clinical symptoms). Patients who developed antibodies against HBsAg (anti-HBsAg seroconversion) are usually considered non-infectious. HBsAg detection by immunoassay is used in blood screening, to establish a diagnosis of hepatitis B infection in the clinical setting (in combination with other disease markers) and to monitor antiviral treatment.
In histopathology, the presence of HBsAg is more commonly demonstrated by the use of the Shikata orcein technique, which uses a natural dye to bind to the antigen in infected liver cells.
Positive HBsAg tests can be due to recent vaccination against Hepatitis B virus but this positivity is unlikely to persist beyond 14 days post-vaccination.
History
It is commonly referred to as the Australia Antigen. This is because it was first isolated by the American research physician and Nobel Prize winner Baruch S. Blumberg in the serum of an Australian Aboriginal person. It was discovered to be part of the virus that caused serum hepatitis by virologist Alfred Prince in 1968.
Heptavax, a "first-generation" hepatitis B vaccine in the 1980s, was made from HBsAg extracted from the blood plasma of hepatitis patients. Current vaccine are made from recombinant HBsAg grown in yeast.
See also
HBcAg
HBeAg |
https://en.wikipedia.org/wiki/Dmitry%20Feichtner-Kozlov | Dmitry Feichtner-Kozlov (born 16 December 1972, in Tomsk, Russia) is a Russian-German mathematician.
He works in the field of Applied and Combinatorial Topology, where he publishes under the name Dmitry N. Kozlov.
Biography
Feichtner-Kozlov obtained his PhD from the Royal Institute of Technology, Stockholm in 1996, with thesis Extremal Combinatorics, Weighting Algorithms, and Topology of Subspaces Arrangements written under the direction of Anders Björner. In 2004, after longer stays at the Mathematical Sciences Research Institute in Berkeley, California, the Massachusetts Institute of Technology, the Institute for Advanced Study in Princeton, New Jersey, the University of Washington in Seattle, the University of Bern, and the Royal Institute of Technology, he assumed the position of assistant professor at ETH Zurich, Switzerland.
Since 2007, he works at the University of Bremen, Germany, where he holds the Chair of Algebra and Geometry, and is the director of the Institute for Algebra, Geometry, Topology and their applications.
Feichtner-Kozlov has done research on various topics, such as: topological methods in combinatorics, including applications to graph colorings;
combinatorially defined polyhedral and cell complexes; combinatorial structures in geometry and topology, such as stratifications and compactifications of spaces; combinatorial aspects of chain complexes, such as coboundary expansion. He has also done interdisciplinary work, e.g., developing rigorous mathematical methods in theoretical distributed computing.
Feichtner-Kozlov is the recipient of the following prizes: Wallenberg prize 2003, Goran Gustafsson prize 2004, European Prize in Combinatorics 2005. The book "Distributed Computing through Combinatorial Topology",
which he wrote together with computer scientists Maurice Herlihy and Sergio Rajsbaum has been selected as a Notable Book on the Best of Computing 2013 list by the Association for Computing Machinery.
He is a managing editor of th |
https://en.wikipedia.org/wiki/Taeha%20Types | Tae Ha Kim, known by his streaming channel Taeha Types, is a mechanical keyboard creator and livestreamer. While known for his commissioned keyboards, his Twitch livestream compose his primary occupation. His channel has influenced the rise of the mechanical keyboard hobby, particularly boosted by his viral video assembling a commission for Fortnite streamer Tfue.
Early life
Tae Ha Kim was born in and raised in California. Prior to streaming, he worked as a software engineer.
Streaming career
Kim began live streaming himself assembling mechanical keyboards in 2018. He was not the first creator to do so, but he focused on making his videos accessible to beginners and creating a platform for keyboard appreciation. The condensed cut of his livestream assembling a keyboard for Fortnite streamer Tfue became a viral hit, with two million views in under two weeks. Kim's Twitch channel is his primary occupation, where he is funded by donations and subscriptions, rather than by commissions. Kim has created keyboards by commission for other livestreamers, including LilyPichu. Tom's Hardware described Kim's popular livestream as being a significant contributor to the growth of the mechanical keyboard hobby.
Kim also makes ASMR typing videos and contributed to a vinyl record of mechanical keyboard sounds released on Trunk Records in 2019. |
https://en.wikipedia.org/wiki/Air%E2%80%93fuel%20ratio | Air–fuel ratio (AFR) is the mass ratio of air to a solid, liquid, or gaseous fuel present in a combustion process. The combustion may take place in a controlled manner such as in an internal combustion engine or industrial furnace, or may result in an explosion (e.g., a dust explosion, gas or vapor explosion or in a thermobaric weapon).
The air–fuel ratio determines whether a mixture is combustible at all, how much energy is being released, and how much unwanted pollutants are produced in the reaction. Typically a range of fuel to air ratios exists, outside of which ignition will not occur. These are known as the lower and upper explosive limits.
In an internal combustion engine or industrial furnace, the air–fuel ratio is an important measure for anti-pollution and performance-tuning reasons. If exactly enough air is provided to completely burn all of the fuel, the ratio is known as the stoichiometric mixture, often abbreviated to stoich. Ratios lower than stoichiometric (where the fuel is in excess) are considered "rich". Rich mixtures are less efficient, but may produce more power and burn cooler. Ratios higher than stoichiometric (where the air is in excess) are considered "lean". Lean mixtures are more efficient but may cause higher temperatures, which can lead to the formation of nitrogen oxides. Some engines are designed with features to allow lean-burn. For precise air–fuel ratio calculations, the oxygen content of combustion air should be specified because of different air density due to different altitude or intake air temperature, possible dilution by ambient water vapor, or enrichment by oxygen additions.
Internal combustion engines
In theory, a stoichiometric mixture has just enough air to completely burn the available fuel. In practice, this is never quite achieved, due primarily to the very short time available in an internal combustion engine for each combustion cycle.
Most of the combustion process is completed in approximately 2 millisecon |
https://en.wikipedia.org/wiki/PRESENT | PRESENT is a lightweight block cipher, developed by the Orange Labs (France), Ruhr University Bochum (Germany) and the Technical University of Denmark in 2007. PRESENT was designed by Andrey Bogdanov, Lars R. Knudsen, Gregor Leander, Christof Paar, Axel Poschmann, Matthew J. B. Robshaw, Yannick Seurin, and C. Vikkelsoe. The algorithm is notable for its compact size (about 2.5 times smaller than AES).
Overview
The block size is 64 bits and the key size can be 80 bit or 128 bit. The non-linear layer is based on a single 4-bit S-box which was designed with hardware optimizations in mind. PRESENT is intended to be used in situations where low-power consumption and high chip efficiency is desired. The International Organization for Standardization and the International Electrotechnical Commission included PRESENT in the new international standard for lightweight cryptographic methods.
Cryptanalysis
A truncated differential attack on 26 out of 31 rounds of PRESENT was suggested in 2014.
Several full-round attacks using biclique cryptanalysis have been introduced on PRESENT.
By design all block ciphers with a block size of 64 bit can have problems with block collisions if they are used with large amounts of data. Therefore, implementations need to make sure that the amount of data encrypted with the same key is limited and rekeying is properly implemented.
Performance
PRESENT uses bit-oriented permutations and is not software-friendly. It is clearly targeted at hardware, where bit-permutations are possible with simple wiring. Performance of PRESENT when evaluated in microcontroller software environment using FELICS (Fair Evaluation of Lightweight Cryptographic Systems), a benchmarking framework for evaluation of software implementations of lightweight cryptographic primitives.
Standardization
PRESENT is included in the following standards.
ISO/IEC 29167-11:2014, Information technology - Automatic identification and data capture techniques - Part 11: Crypto suit |
https://en.wikipedia.org/wiki/ORF7a | ORF7a (also known by several other names, including SARS coronavirus X4, SARS-X4, ORF7a, or U122) is a gene found in coronaviruses of the Betacoronavirus genus. It expresses the Betacoronavirus NS7A protein, a type I transmembrane protein with an immunoglobulin-like protein domain. It was first discovered in SARS-CoV, the virus that causes severe acute respiratory syndrome (SARS). The homolog in SARS-CoV-2, the virus that causes COVID-19, has about 85% sequence identity to the SARS-CoV protein.
Function
A number of possible functions for the ORF7a protein have been described. The primary function is thought to be immunomodulation and interferon antagonism. The protein is not essential for viral replication.
Viral protein interactions
Studies in SARS-CoV suggest that the protein forms protein-protein interactions with spike protein and ORF3a, and is present in mature virions, making it a minor viral structural protein. It is unclear if this occurs in SARS-CoV-2. It may have a role in viral assembly.
Host effects
A number of interactions with host proteins and effects on host cell processes have been described. The SARS-CoV ORF7a protein has been reported to have binding activity to integrin I domains.
It has also been reported to induce apoptosis via a caspase dependent
pathway. Also, it contains a motif which has been demonstrated to mediate COPII dependent transport out of the endoplasmic reticulum, and the protein is targeted to the Golgi apparatus.
In SARS-CoV-2, ORF7a protein has been described as an effective interferon antagonist. The SARS-CoV-2 protein may have immunomodulatory effects through interaction with monocytes.
Structure
The ORF7a protein is a transmembrane protein with 121 amino acid residues in SARS-CoV-2 and 122 in SARS-CoV. It is a type I transmembrane protein with an N-terminal signal peptide, an ectodomain that has an immunoglobulin fold, and a C-terminal endoplasmic reticulum retention signal sequence. The structure contains seven beta |
https://en.wikipedia.org/wiki/Metamaterials%3A%20Physics%20and%20Engineering%20Explorations | Metamaterials: Physics and Engineering Explorations is a book length introduction to the fundamental research and advancements in electromagnetic composite substances known as electromagnetic metamaterials. The discussion encompasses examination of the physics of metamaterial interactions, the designs, and the perspectives of engineering regarding these materials. Also included throughout the book are potential applications, which are discussed at various points in each section of each chapter. The book encompasses a variety of theoretical, numerical, and experimental perspectives.
This book has been cited by a few hundred other peer-reviewed research efforts, mostly peer-reviewed science articles.
Authors
Nader Engheta received his Ph.D. in Electrical Engineering (with a minor in Physics), in 1982 from the California Institute of Technology. Currently he is a Professor of Electrical and Systems Engineering, and Professor of Bioengineering at the University of Pennsylvania. His current research activities include metamaterials, plasmonics, nano-optics, nanophotonics, bio-inspired sensing and imaging, miniaturized antennas and nanoantennas.
Richard W. Ziolkowski received both his M.S. and Ph.D. in physics, in 1975 and 1980, respectively from the University of Illinois at Urbana-Champaign. Currently he has a dual appointment at the University of Arizona. He is a Professor of Electrical and Computer Engineering, and a Professor of the Optical Sciences. His current research includes metamaterial physics and engineering related to low frequency and high frequency antenna systems, and includes nanoparticle lasers.
Through their respective research, both Engheta and Ziolkowski have each contributed significantly to advancing metamaterials. Ziolkowski has been described as being at the leading edge of metamaterials research since a Defense Advanced Research Projects Agency (DARPA) workshop, in November, 1999.
Research
Nader Engheta and Richard W. Ziolkowski, ar |
https://en.wikipedia.org/wiki/High-end%20audio | High-end audio is a class of consumer home audio equipment marketed to audiophiles on the basis of high price or quality, and esoteric or novel sound reproduction technologies. The term can refer simply to the price, to the build quality of the components, or to the subjective or objective quality of sound reproduction.
Definition
The distinction between the terms high end and high fidelity is not well defined. According to one industry commentator, high-end could be defined as, "Gear below which's price and performance one could not go without compromising the music and the sound." Harry Pearson, founder of The Absolute Sound magazine, is widely acknowledged to have coined the term high-end audio.
Costs
High-end audio equipment can be extremely expensive. It is sometimes referred to as cost-no-object equipment. Audiophile equipment can encompass the full range from budget to high-end in terms of price.
Fidelity assessment
The fidelity of sound reproduction may be assessed aurally or using audio system measurements.
The human sense of hearing is subjective and difficult to define. Psychoacoustics is a division of acoustics that studies this field.
Measurements can be deceiving; high or low figures of certain technical characteristics do not necessarily offer a good representation of how the equipment sounds to each person. For example, some valve amplifiers produce greater amounts of total harmonic distortion, but this type of distortion (2nd harmonic) is not as disturbing to the ear as the higher-order distortions produced by poorly designed transistor equipment.
The validity of certain products is often questioned. These include accessories such as speaker wires utilizing exotic materials (such as oxygen-free copper) and construction geometries, cable stands for lifting them off the floor (as a way to control mechanically induced vibrations), connectors, sprays and other tweaks.
See also
Audio noise measurement
Broadcast quality
Professional audio
S |
https://en.wikipedia.org/wiki/Urologic%20chronic%20pelvic%20pain%20syndrome | Urologic chronic pelvic pain syndrome (UCPPS) is ongoing bladder pain in either sex, chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men and interstitial cystitis or painful bladder syndrome (IC/PBS) in women.
It was coined as an umbrella term for use in research into urologic pain syndromes in men and women.
Treatment
Multimodal therapy is the most successful treatment option in chronic pelvic pain, and includes physical therapy, myofascial trigger point release, relaxation techniques, α-blockers, and phytotherapy. The UPOINT diagnostic approach suggests that antibiotics are not recommended unless there is clear evidence of infection.
Research
In 2007, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the United States National Institutes of Health (NIH), began using UCPPS as a term to refer to chronic pelvic pain syndromes (interstitial cystitis|interstitial cystitis/bladder pain syndrome (IC/BPS) in women and chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men).
MAPP Research Network
The NIDDK established the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network in 2008.
MAPP Network scientists use a whole–body, systemic approach to the study of UCPPS, as well as investigating potential relationships between UCPPS and other chronic conditions that are sometimes seen in IC/PBS and CP/CPPS patients, such as irritable bowel syndrome, fibromyalgia, and chronic fatigue syndrome. |
https://en.wikipedia.org/wiki/Selected%20reaction%20monitoring | Selected reaction monitoring (SRM), also called Multiple reaction monitoring, (MRM), is a method used in tandem mass spectrometry in which an ion of a particular mass is selected in the first stage of a tandem mass spectrometer and an ion product of a fragmentation reaction of the precursor ions is selected in the second mass spectrometer stage for detection.
Variants
A general case of SRM can be represented by
where the precursor ion ABCD+ is selected by the first stage of mass spectrometry (MS1), dissociates into molecule AB and product ion CD+, and the latter is selected by the second stage of mass spectrometry (MS2) and detected. The precursor and product ion pair is called a SRM "transition".
Consecutive reaction monitoring (CRM) is the serial application of three or more stages of mass spectrometry to SRM, represented in a simple case by
where ABCD+ is selected by MS1, dissociates into molecule AB and ion CD+. The ion is selected in the second mass spectrometry stage MS2 then undergoes further fragmentation to form ion D+ which is selected in the third mass spectrometry stage MS3 and detected.
Multiple reaction monitoring (MRM) is the application of selected reaction monitoring to multiple product ions from one or more precursor ions, for example
where ABCD+ is selected by MS1 and dissociates by two pathways, forming either AB+ or CD+. The ions are selected sequentially by MS2 and detected. Parallel reaction monitoring (PRM) is the application of SRM with parallel detection of all transitions in a single analysis using a high resolution mass spectrometer.
Proteomics
SRM can be used for targeted quantitative proteomics by mass spectrometry. Following ionization in, for example, an electrospray source, a peptide precursor is first isolated to obtain a substantial ion population of mostly the intended species. This population is then fragmented to yield product ions whose signal abundances are indicative of the abundance of the peptide in the sample. Th |
https://en.wikipedia.org/wiki/Karl%20Zimmer | Karl Günter Zimmer (12 July 1911 – 29 February 1988), PhD, was a German nuclear chemist who is best known for his work in understanding the ionizing radiation on Deoxyribonucleic acid (DNA).
In 1935, he published the major work, Über die Natur der Genmutation und der Genstruktur, with N. V. Timofeev-Resovskij, and Max Delbrück; it was considered to be a major advance in understanding the nature of gene mutation and gene structure. From 1945-55,, Zimmer was participated in the former Soviet program of nuclear weapons but left Russia to eventually settle in Germany.
Education
Zimmer obtained his doctorate in 1934 with a thesis on photochemistry.
Career
In Germany
Early on, Zimmer worked as an advisor in radiotherapeutic physics in a radiological hospital and as an employee of Auergesellschaft in Berlin. However, he completed most of his theoretical work at the Kaiser-Wilhelm Gesellschaft's Institut für Hirnforschung (KWIH, Kaiser Wilhelm Institute for Brain Research) in Berlin-Buch. Zimmer worked in N. V. Timofeev-Resovskij's genetics department at the KWIH. Timofeev-Resovskij, a citizen of the Soviet Union, worked in Germany starting in 1924, and he stayed even after Adolf Hitler came to power in 1933. Very early in Zimmer's career, in 1935, he published the major work, Über die Natur der Genmutation und der Genstruktur, with Timofeev-Resovskij, and Max Delbrück; it was considered to be a major advance in understanding the nature of gene mutation and gene structure. At Auergesellschaft, Zimmer collaborated with Nikolaus Riehl, director of scientific research at the works.
At the close of World War II, Russia had special search teams operating in Austria and Germany, especially in Berlin, to identify and "requisition" equipment, materiel, intellectual property, and personnel useful to the Soviet atomic bomb project. The exploitation teams were under the Russian Alsos and they were headed by Lavrenij Beria's deputy, Colonel General A. P. Zavenyagin. These team |
https://en.wikipedia.org/wiki/Cfr10I/Bse634I | In molecular biology, the Cfr10I/Bse634I family of restriction endonucleases includes the type II restriction endonucleases Cfr10I and Bse634I. They exhibit a conserved tetrameric architecture that is of functional importance, wherein two dimers are arranged, back-to-back, with their putative DNA-binding clefts facing opposite directions. These clefts are formed between two monomers that interact, mainly via hydrophobic interactions supported by a few hydrogen bonds, to form a U-shaped dimer. Each monomer is folded to form a compact alpha-beta structure, whose core is made up of a five-stranded mixed beta-sheet. The monomer may be split into separate N-terminal and C-terminal subdomains at a hinge located in helix alpha3. Both Cfr10I and Bse634I recognise the double-stranded sequence RCCGGY and cleave after the purine R.
Recognition sequence Cut
5' RCCGGY 5' ---R CCGGY--- 3'
3' YGGCCR 3' ---YGGCC R--- 5' |
https://en.wikipedia.org/wiki/DIN%2066003 | The German standard DIN 66003, also known as Code page 1011 (CCSID 1011; abbreviated CP1011) by IBM, Code page 20106 (abbreviated CP20106) by Microsoft and D7DEC by Oracle, is a modification of 7-bit ASCII with adaptations for the German language, replacing certain symbol characters with umlauts and the eszett. It is the German national version of ISO/IEC 646 (ISO 646-DE), and also a localised option in DEC's National Replacement Character Set (NRCS) for their VT220 terminals.
It is registered with the ISO-IR registry for use with ISO/IEC 2022 as ISO-IR-21. Kermit calls it , but also accepts the IANA-registered name . Other IANA-registered names include , and simply .
Code page layout
See also
National Replacement Character Set (NRCS) |
https://en.wikipedia.org/wiki/Physics%20Instructional%20Resource%20Association | The Physics Instructional Association (PIRA) is an American association of physics education professionals and enthusiasts. Members are physics teachers, physics administrators, physics educational support staff and physics students. Interests cover all aspects of physics education with an emphasis on demonstrations, laboratories and outreach.
The association is also responsible for maintaining the Demonstration Classification Scheme (DCS), a standardized scheme for categorization of physics demonstrations.
Affiliations
PIRA holds annual meetings during the summer meeting of the American Association of Physics Teachers. It is sponsored by the Apparatus Committee and annually hosts the Lecture Demonstration Workshop. PIRA assists or hosts the Physics Demonstrations Show at each summer meeting when the hosting institution requests.
Demonstration bibliography
PIRA has continually updated the Demonstration Bibliography since its inception in the 1980s. It is based on a unique numbering system called the Demonstration Classification Scheme (DCS). The scheme originated from the demonstrations catalog used at the University of Minnesota.
PIRA has also generated a subset of this list called the PIRA 200. These 200 demonstrations are the recommended basic collection for any physics department.
See also
Scientific demonstration |
https://en.wikipedia.org/wiki/Beth%20definability | In mathematical logic, Beth definability is a result that connects implicit definability of a property to its explicit definability. Specifically Beth definability states that the two senses of definability are equivalent.
First-order logic has the Beth definability property.
Statement
For first-order logic, the theorem states that, given a theory T in the language L' ⊇ L and a formula φ in L', then the following are equivalent:
for any two models A and B of T such that A|L = B|L (where A|L is the reduct of A to L), it is the case that A ⊨ φ[a] if and only if B ⊨ φ[a] (for all tuples a of A);
φ is equivalent modulo T to a formula ψ in L.
Less formally: a property is implicitly definable in a theory in language L (via a formula φ of an extended language L') only if that property is explicitly definable in that theory (by formula ψ in the original language L).
Clearly the converse holds as well, so that we have an equivalence between implicit and explicit definability. That is, a "property" is explicitly definable with respect to a theory if and only if it is implicitly definable.
The theorem does not hold if the condition is restricted to finite models. We may have A ⊨ φ[a] if and only if B ⊨ φ[a] for all pairs A,B of finite models without there being any L-formula ψ equivalent to φ modulo T.
The result was first proven by Evert Willem Beth.
See also
Sources
Wilfrid Hodges A Shorter Model Theory. Cambridge University Press, 1997.
Mathematical logic
Mathematical structures
Model theory
Theorems in the foundations of mathematics |
https://en.wikipedia.org/wiki/Lactose%20intolerance | Lactose intolerance is caused by a lessened ability or a complete inability to digest lactose, a sugar found in dairy products. Humans vary in the amount of lactose they can tolerate before symptoms develop. Symptoms may include abdominal pain, bloating, diarrhea, flatulence, and nausea. These symptoms typically start thirty minutes to two hours after eating or drinking something containing lactose, with the severity typically depending on the amount consumed. Lactose intolerance does not cause damage to the gastrointestinal tract.
Lactose intolerance is due to the lack of the enzyme lactase in the small intestines to break lactose down into glucose and galactose. There are four types: primary, secondary, developmental, and congenital. Primary lactose intolerance occurs as the amount of lactase declines as people grow up. Secondary lactose intolerance is due to injury to the small intestine. Such injury could be the result of infection, celiac disease, inflammatory bowel disease, or other diseases. Developmental lactose intolerance may occur in premature babies and usually improves over a short period of time. Congenital lactose intolerance is an extremely rare genetic disorder in which little or no lactase is made from birth. The reduction of lactase production starts typically in late childhood or early adulthood, but prevalence increases with age.
Diagnosis may be confirmed if symptoms resolve following eliminating lactose from the diet. Other supporting tests include a hydrogen breath test and a stool acidity test. Other conditions that may produce similar symptoms include irritable bowel syndrome, celiac disease, and inflammatory bowel disease. Lactose intolerance is different from a milk allergy. Management is typically by decreasing the amount of lactose in the diet, taking lactase supplements, or treating the underlying disease. People are typically able to drink at least one cup of milk without developing symptoms, with greater amounts tolerated if drunk |
https://en.wikipedia.org/wiki/%282-Nitrophenyl%29acetic%20acid | 2-Nitrophenylacetic acid is an organic compound used in organic synthesis that has also been used as an herbicide. It is a derivative of phenylacetic acid, containing a phenyl functional group, a carboxylic acid functional group, and a nitro functional group. It is an important reagent for many organic reactions, especially for the formation of heterocycles.
Synthesis
This compound may be prepared by the nitration of phenylacetic acid.
Applications
In organic synthesis, 2-nitrophenylacetic acid can be used as a protecting group for primary alcohols. The alcohol is esterified with 2-nitrophenylacetic acid, proceeding through the acid chloride or acid anhydride. The acid itself can also protect the alcohol through the Mitsunobu reaction: reacting the alcohol and the acid with diethyl azidocarboxylate and triphenylphosphine in dichloromethane. The protecting group is selectively removed using zinc and ammonium chloride, and is compatible with other existing alcohol protecting groups.
In addition, 2-nitrophenylacetic acid is a precursor for many heterocycles. Complete reduction of 2-nitrophenylacetic acid yields anilines, which quickly cyclize to form lactams. Partial reductive cyclization of the acids using weaker reducing agents forms hydroxamic acids.
Both of these processes are useful in the synthesis of many biologically active molecules. 2-nitrophenylacetic acid is a precursor of quindoline, which although it does not have many practical applications on its own, quindoline derivatives and modifications can be treated as enzyme inhibitors and anticancer agents.
Derivatives of 2-nitrophenylacetic acids are useful in total synthesis for their ability to form heterocycles. 2-nitrophenylacetic acid is a precursor to (-)-phaitanthrin D, a clinically useful molecule originally isolated from the Phaius mishmensis orchid. The carboxylic acid on the 2-nitrophenylacetic acid is first protected using menthol, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDCl), hydro |
https://en.wikipedia.org/wiki/Phenol%20formaldehyde%20resin | Phenol formaldehyde resins (PF) (phenolic resins or phenoplasts) are synthetic polymers obtained by the reaction of phenol or substituted phenol with formaldehyde. Used as the basis for Bakelite, PFs were the first commercial synthetic resins (plastics). They have been widely used for the production of molded products including billiard balls, laboratory countertops, and as coatings and adhesives. They were at one time the primary material used for the production of circuit boards but have been largely replaced with epoxy resins and fiberglass cloth, as with fire-resistant FR-4 circuit board materials.
There are two main production methods. One reacts phenol and formaldehyde directly to produce a thermosetting network polymer, while the other restricts the formaldehyde to produce a prepolymer known as novolac which can be moulded and then cured with the addition of more formaldehyde and heat. There are many variations in both production and input materials that are used to produce a wide variety of resins for special purposes.
Formation and structure
Phenol-formaldehyde resins, as a group, are formed by a step-growth polymerization reaction that can be either acid- or base-catalysed. Since formaldehyde exists predominantly in solution as a dynamic equilibrium of methylene glycol oligomers, the concentration of the reactive form of formaldehyde depends on temperature and pH.
Phenol reacts with formaldehyde at the ortho and para sites (sites 2, 4 and 6) allowing up to 3 units of formaldehyde to attach to the ring. The initial reaction in all cases involves the formation of a hydroxymethyl phenol:
HOC6H5 + CH2O → HOC6H4CH2OH
The hydroxymethyl group is capable of reacting with either another free ortho or para site, or with another hydroxymethyl group. The first reaction gives a methylene bridge, and the second forms an ether bridge:
HOC6H4CH2OH + HOC6H5 → (HOC6H4)2CH2 + H2O
2 HOC6H4CH2OH → (HOC6H4CH2)2O + H2O
The diphenol (HOC6H4)2CH2 (somet |
https://en.wikipedia.org/wiki/Green%20Light | Green Light, green light, green-light or greenlight may refer to:
Green-colored light, part of the visible spectrum
Arts, entertainment, and media
Films and television
Green Light (1937 film), starring Errol Flynn
Green Light (2002 film), a Turkish film written and directed by Faruk Aksoy
"Green Light" (Breaking Bad), a third-season episode of Breaking Bad
Greenlight, formal approval of a project to move forward
Literature
Green Light, a 1935 novel by Lloyd C. Douglas
"Green Light", the final passage of F. Scott Fitzgerald's novel The Great Gatsby
Greenlights (book), a 2020 book by Matthew McConaughey
Music
Albums
Green Light (Bonnie Raitt album), 1982
Green Light (Cliff Richard album), 1978
The Green Light, a 2009 mixtape by Bow Wow
Songs
"Green Light" (Cliff Richard song) (1979)
"Green Light" (Beyoncé song) (2006)
"Green Light" (John Legend song) (2008)
"Green Light" (Roll Deep song) (2010)
"Green Light" (Lorde song) (2017)
"Green Light" (Valery Leontiev song) (1984)
"Green Light", by the American Breed from Bend Me, Shape Me (1968)
"Green Light", by Girls' Generation from Lion Heart
"Green Light", by Hank Thompson (1954)
"Green Light", by Lil Durk from Love Songs 4 the Streets 2
"Green Light", by R. Kelly from Write Me Back
"Green Light", by Sonic Youth from Evol
"Green Light", by the Bicycles from Oh No, It's Love
"Green Lights", by Aloe Blacc (2011)
"Greenlight" (Pitbull song) (2016)
"Green Lights", by Sarah Jarosz from Undercurrent (2016)
"Green Light", by Kylie Minogue from Tension (2023)
"Greenlight", by 5 Seconds of Summer from 5 Seconds of Summer
"Greenlight", by Enisa Nikaj which represented New York in the American Song Contest
"Greenlights" (song), by Krewella
Computing and technology
Greenlight (Internet service), a fiber-optic Internet service provided by the city of Wilson, North Carolina, US
Greenlight Networks, a fiber-optic Internet service in Rochester, New York, US
Steam Greenlight, a service part of Val |
https://en.wikipedia.org/wiki/UML-RSDS | UML-RSDS is a lightweight Model-driven engineering (MDE) and Model transformation tool supporting the UML 2.5 class diagram notation and OCL 2.4 Object Constraint Language. It supports code-generation in multiple 3GLs: Java, C#, C++, Python, Go, Swift and ANSI C.
The toolset has been defined as an Eclipse project AgileUML under the modeling category.
The toolset originated from EPSRC-funded research at Imperial College and King's College London in the period 1996–2014. It was publicly released in 2010 and defined as an Eclipse project in 2019. It is now supported by AgileMDE Ltd: agilemde.co.uk.
One motivation of the tools has been to provide a means for general software practitioners to use MDE in a flexible manner, to support agile development using MDE. The tool has been applied to financial software development and to many different kinds of transformation problems, for example
Language characteristics
The main specification notations in UML-RSDS are UML class diagrams and use cases, together with Object Constraint Language (OCL)
expressions, used to define invariants and operation pre and post-conditions. Either a graphical or textual notation can be used for UML-RSDS
specifications.
For example, a simple class specification could be written as:
class Person {
attribute age: int;
attribute name: String;
operation birthday()
pre: true
post: age = age@pre + 1;
}
Transformations are defined as use cases together with constraints expressing how result data is derived from input data. Thus a declarative specification style similar to the QVT relations language is supported, but without the need to define additional syntax or language elements - only OCL is used. For example, to copy every person instance to a 'PersonRecord' with a 'data' attribute formed from the name and age, it is sufficient to write:
usecase copyPersons {
Person::
PersonRecord->exists( r | r.data = name + age )
}
Verification procedures have been defined for this sty |
https://en.wikipedia.org/wiki/Fill%20and%20finish | In the pharmaceutical industry, fill and finish (also referred to as fill finish, fill-finish or fill/finish) is the process of filling vials with vaccine, biological and pharmaceutical Drug Substances (DS) and finishing the process of packaging the medicine for distribution. Many vaccine manufacturers use third parties to fill and finish their vaccines.
The fill/finish process is a common bottleneck in the manufacturing and deployment of vaccines.
To address this problem, in 2013 the U.S. federal government created the Fill Finish Manufacturing Network, a network of third-party provider contracts intended to perform fill and finish operations for vaccines against future infectious diseases. As part of its response to the COVID-19 pandemic, the UK government has provided financial support for fill and finish operations. |
https://en.wikipedia.org/wiki/Synchronous%20Serial%20Port | A Synchronous Serial Port (SSP) is a controller that supports the Serial Peripheral Interface (SPI), 4-wire Synchronous Serial Interface (SSI), and Microwire serial buses. A SSP uses a master-slave paradigm to communicate across its connected bus.
See also
Serial Peripheral Interface Bus
Serial buses |
https://en.wikipedia.org/wiki/Polyploid%20complex | A polyploid complex, also called a diploid-polyploid complex, is a group of interrelated and interbreeding species that also have differing levels of ploidy that can allow interbreeding.
A polyploid complex was described by E. B. Babcock and G. Ledyard Stebbins in their 1938 monograph The American Species of Crepis: their interrelationships and distribution as affected by polyploidy and apomixis. In Crepis and some other perennial plant species, a polyploid complex may arise where there are at least two genetically isolated diploid populations, in addition to auto- and allopolyploid derivatives that coexist and interbreed. Thus a complex network of interrelated forms may exist where the polyploid forms allow for intermediate forms between the diploid species that are otherwise unable to interbreed.
This complex situation does not fit well within the biological species concept of Ernst Mayr which defines a species as "groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups".
In many diploid-polyploid complexes the polyploid hybrid members reproduce asexually while diploids reproduce sexually. Thus polyploidy is related to the phenomenon called "geographic parthenogenesis" by zoologist Albert Vandel, that asexual organisms often have greater geographic ranges than their sexual relatives. It is not known which of the associated factors is the major determiner of geographic parthenogenesis, hybridization, polyploidy, or asexual reproduction.
See also
Species complex |
https://en.wikipedia.org/wiki/CYP13%20family | Cytochrome P450, family 13, also known as CYP13, is a nematoda cytochrome P450 monooxygenase family. The first gene identified in this family is the CYP13A1 from the Caenorhabditis elegans.
CYP13 can be divided into subfamily CYP13A and CYP13B, and the CYP13B was named CYP16 family at the beginning of its discovery, which have been discontinued and been changed to the current name, because its genetic relationship with the subfamily CYP13A.
Genes in C. elegans |
https://en.wikipedia.org/wiki/165th%20meridian%20west | The meridian 165° west of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, North America, the Pacific Ocean, the Southern Ocean, and Antarctica to the South Pole.
The 165th meridian west forms a great circle with the 15th meridian east.
The Samoa Time Zone and Phoenix Islands Time Zone is based on the mean solar time of this meridian.
From Pole to Pole
Starting at the North Pole and heading south to the South Pole, the 165th meridian west passes through:
{| class="wikitable plainrowheaders"
! scope="col" width="130" | Co-ordinates
! scope="col" width="120" | Country, territory or sea
! scope="col" | Notes
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Arctic Ocean
| style="background:#b0e0e6;" |
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Chukchi Sea
| style="background:#b0e0e6;" |
|-
|
! scope="row" |
| Alaska
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Chukchi Sea
| style="background:#b0e0e6;" | Kotzebue Sound
|-
|
! scope="row" |
| Alaska — Seward Peninsula
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Norton Sound
|-
|
! scope="row" |
| Alaska — Yukon–Kuskokwim Delta
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Bering Sea
| style="background:#b0e0e6;" | Passing just west of Unimak Island, Alaska, (at )
|-
|
! scope="row" |
| Alaska — Tigalda Island
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Pacific Ocean
| style="background:#b0e0e6;" |
|-
| style="background:#b0e0e6;" |
! scope="row" style="background:#b0e0e6;" | Southern Ocean
| style="background:#b0e0e6;" |
|-
|
! scope="row" | Antarctica
| Ross Dependency, claimed by
|-
|}
See also
164th meridian west
166th meridian west
w165 meridian west |
https://en.wikipedia.org/wiki/Hoopla%20%28digital%20media%20service%29 | Hoopla (stylized as hoopla) is a web and mobile (Android/iOS) library media streaming platform launched in 2010 for audio books, comics, e-books, movies, music, and TV. Patrons of a library that supports Hoopla have access to its collection of digital media.
Hoopla Digital is a division of Midwest Tape.
Business model
Hoopla is free-of-charge for patrons of participating libraries. The content is paid for by library systems, using a "per circulation transaction model".
Content
Hoopla claims to have over 500,000 content titles across six formats, including over 25,000 comic books. As of November 2016, Hoopla's content comprised 35% audiobooks (for which Hoopla has contracts with publishers such as Blackstone Audio, HarperCollins, Simon & Schuster Audio, Tantor Audio, and others), followed by 22% movies (for which Hoopla has motion picture contracts with publishers such as Disney, Lionsgate, Starz, Warner Bros., and others), 19% music, 12% ebooks, 6% comics, and 6% television. One drawback is that Hoopla has few new bestsellers.
Areas Served
Hoopla expanded to serve Australia and New Zealand in June 2021.
Technology
Hoopla content can be borrowed and consumed on the web, or via the native Android or iOS apps.
Parent company
John Eldred and Jeff Jankowski founded Hoopla's parent company, Midwest Tape, in 1989. Midwest Tape is a library vendor of physical media such as audiobooks, CDs, and DVD/Blu-ray.
Controversy
Hoopla and Midwest Tapes were censured by the Library Freedom Project and Library Futures in a joint statement for hosting what it described as "fascist propaganda", including a recent English translation of A New Nobility of Blood and Soil by Richard Walther Darré of the SS and books related to Holocaust denial, in public library collections without the input from the staff. Criticism was also directed at the inclusion of books on homosexuality, abortion, and vaccines claimed by the Library Freedom Project and Library Futures to be misinformation. |
https://en.wikipedia.org/wiki/Phragmen%E2%80%93Brouwer%20theorem | In topology, the Phragmén–Brouwer theorem, introduced by Lars Edvard Phragmén and Luitzen Egbertus Jan Brouwer, states that if X is a normal connected locally connected topological space, then the following two properties are equivalent:
If A and B are disjoint closed subsets whose union separates X, then either A or B separates X.
X is unicoherent, meaning that if X is the union of two closed connected subsets, then their intersection is connected or empty.
The theorem remains true with the weaker condition that A and B be separated. |
https://en.wikipedia.org/wiki/Hostapd | hostapd (host access point daemon) is a user space daemon software enabling a network interface card to act as an access point and authentication server. There are three implementations: Jouni Malinen's hostapd, OpenBSD's hostapd and Devicescape's hostapd.
Jouni Malinen's hostapd
Jouni Malinen's hostapd is a user space daemon for access point and authentication servers. It can be used to create a wireless hotspot using a Linux computer. It implements IEEE 802.11 access point management, IEEE 802.1X/WPA/WPA2/EAP Authenticators, RADIUS client, EAP server, and RADIUS authentication server. The current version supports Linux (Host AP, MadWifi, Prism54 and some of the drivers which use the kernel's mac80211 subsystem), QNX, FreeBSD (net80211), and DragonFlyBSD.
OpenBSD's hostapd
OpenBSD's hostapd is a user space daemon that helps to improve roaming and monitoring of OpenBSD-based wireless networks. It implements Inter Access Point Protocol (IAPP) for exchanging station association information between access points. It can trigger a set of actions like frame injection or logging when receiving specified IEEE 802.11 frames.
Devicescape's hostapd
The Open Wireless Linux version of hostapd. It is kept as close as possible to the original open source release, but with OWL specific packaging and defaults.
The website appears to be dead (April 2013), probably as the project itself.
See also
HostAP |
https://en.wikipedia.org/wiki/E-Bullion | e-Bullion was an Internet-based digital gold currency founded by Jim and Pamela Fayed of Moorpark, California, as part of their Goldfinger Coin & Bullion group of companies. The company was incorporated in 2000 and launched on July 4, 2001. Similar to competing systems such as e-gold, e-Bullion allowed for the instant transfer of gold and silver between user accounts. e-Bullion was a registered legal corporate entity of Panama.
From 2001 to 2008 e-Bullion grew to have over one million users and substantial account transaction volume, and reserves of approximately 50,000 ounces of gold bullion. The company was a competitor to e-gold.com and goldmoney.com.
In 2008, co-founder, Pamela Fayed, was murdered, leading to the indictment, trial and conviction of her husband Jim Fayed for hiring her murder. Fayed was sentenced to death, and is currently on death row in California. As a result of the murder, the U.S. Government seized all of the assets of e-Bullion, resulting in the closure of the company in August 2008.
Features
E-Bullion simply provided a way for users to hold and transfer balances in gold and silver. The company also offered a debit card to U.S. customers, which enabled them to convert their bullion balances to USD and withdraw at an automated teller machine (ATM) or use it for debit purchases.
e-Bullion provided its own in-house currency exchange service through Goldfinger Coin & Bullion, Inc. An e-Bullion account could be funded directly via wire transfer from a bank account.
e-Bullion was the first DGC to issue a debit card linked to an account.
e-Bullion was the first DGC to use CRYPTOCard security tokens to protect user accounts from unauthorized access.
Goldfinger Bullion Reserve Corporation, a sister company of e-Bullion, held the precious metals in bullion storage vaults located in Los Angeles, and at the Perth Mint in Australia.
2008 Murder of e-Bullion Principal
The Fayeds had a troubled marriage which eventually led to divorce proceedings |
https://en.wikipedia.org/wiki/Logic%20family | In computer engineering, a logic family is one of two related concepts:
A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply characteristics within a family. Many logic families were produced as individual components, each containing one or a few related basic logical functions, which could be used as "building-blocks" to create systems or as so-called "glue" to interconnect more complex integrated circuits.
A logic family may also be a set of techniques used to implement logic within VLSI integrated circuits such as central processors, memories, or other complex functions. Some such logic families use static techniques to minimize design complexity. Other such logic families, such as domino logic, use clocked dynamic techniques to minimize size, power consumption and delay.
Before the widespread use of integrated circuits, various solid-state and vacuum-tube logic systems were used but these were never as standardized and interoperable as the integrated-circuit devices. The most common logic family in modern semiconductor devices is metal–oxide–semiconductor (MOS) logic, due to low power consumption, small transistor sizes, and high transistor density.
Technologies
The list of packaged building-block logic families can be divided into categories, listed here in roughly chronological order of introduction, along with their usual abbreviations:
Resistor–transistor logic (RTL)
Direct-coupled transistor logic (DCTL)
Direct-coupled unipolar transistor logic (DCUTL)
Resistor–capacitor–transistor logic (RCTL)
Emitter-coupled logic (ECL)
Positive emitter-coupled logic (PECL)
Low-voltage PECL (LVPECL)
Complementary transistor micrologic (CTuL)
Diode–transistor logic (DTL)
Complemented transistor diode logic (CTDL)
High-threshold logic (HTL)
Transistor–transistor logic (TTL)
Metal–oxide–semiconductor (MO |
https://en.wikipedia.org/wiki/Mark%20Leon | Mark Leon (1962 - 2018) was a former civil servant with NASA Ames Research Center. His primary work was in education and communication systems.
Early life
Mark Leon grew up in a rather rough East San Jose neighborhood, and graduated from James Lick High School in 1980. He originally began taking a slightly more academic route to life when he began hiding in the library from other high school students who were attempting to beat him up.
He also attended San Jose State University and won a silver medal in the 1985 Collegiate National Judo Championships. He received his bachelor's degree in electrical engineering.
Communications work
In the 1980s Leon was instrumental in establishing trans-Atlantic communication between American, French and English space agencies. In the 1990s he completed the first audio/video link to Antarctica. This was thought to be impossible at the time.
Affiliation with FIRST Robotics
For many years Mark Leon worked as a Master of Ceremonies in many FIRST robotics competition events both on and off season. He was particularly well known for wearing a bright blue NASA coat and dying his hair the same color for these events and coined the phrase "Do the math, Save the world". He was widely cited as an inspiration to many high school students to build robots and impacted many career choices. He is also credited with the existence of a large number of FRC teams.
Robotics Alliance Project
Beginning in 1998 Mark moved to the Robotics Alliance Project at NASA Ames. This department works primarily in educational and outreach projects and was estimated in 2006 to have reached more than 100,000 middle and high school students. He also ran the Ames Robotics Academy every summer. |
https://en.wikipedia.org/wiki/Eduardo%20Reck%20Miranda | Eduardo Reck Miranda (born 1963) is a Brazilian composer of chamber and electroacoustic pieces but is most notable in the United Kingdom for his scientific research into computer music, particularly in the field of human-machine interfaces where brain waves will replace keyboards and voice commands to permit the disabled to express themselves musically.
Biography
Early life
Miranda was born in Porto Alegre, Brazil. As one of the largest cities in Southern Brazil and a cultural, political and economical center, Porto Alegre had significant influence on Miranda's music.
Education
In the early 1990s, Miranda attended the University of Vale do Rio dos Sinos (UNISINOS) in Brazil where he received a degree in Data Processing Technology in 1985. Miranda then attended the Federal University of Rio Grande do Sul (UFRGS) where he studied music composition. Desiring to learn more about music technology and experience more of the world, Miranda made his way to the United Kingdom, where he started his post-graduate research studies at the University of York. At York, he developed an in-depth study into musical composition using cellular automata. In 1991, he received his MSc in Music Technology from York. After receiving his MSc, Miranda went briefly to Germany to study algorithmic composition at the Zentrum für Kunst und Medientechnologie in Karlsruhe.
In 1992, Miranda gained admittance to the Faculty of Music of the University of Edinburgh in Scotland where he obtained his PhD in the combined fields of music and artificial intelligence in 1995. For his doctoral thesis, he focused on musical knowledge representation, machine learning of music and software sound synthesis.
Experiences
After receiving his PhD, Miranda worked at the Edinburgh Parallel Computing Centre (EPCC). At EPCC, he developed Chaosynth, an innovative granular synthesis software that uses cellular automata to generate complex sound spectra.
In the mid-1990s, Miranda joined the Department of Music at the |
https://en.wikipedia.org/wiki/Plasmon | In physics, a plasmon is a quantum of plasma oscillation. Just as light (an optical oscillation) consists of photons, the plasma oscillation consists of plasmons. The plasmon can be considered as a quasiparticle since it arises from the quantization of plasma oscillations, just like phonons are quantizations of mechanical vibrations. Thus, plasmons are collective (a discrete number) oscillations of the free electron gas density. For example, at optical frequencies, plasmons can couple with a photon to create another quasiparticle called a plasmon polariton.
Derivation
The plasmon was initially proposed in 1952 by David Pines and David Bohm and was shown to arise from a Hamiltonian for the long-range electron-electron correlations.
Since plasmons are the quantization of classical plasma oscillations, most of their properties can be derived directly from Maxwell's equations.
Explanation
Plasmons can be described in the classical picture as an oscillation of electron density with respect to the fixed positive ions in a metal. To visualize a plasma oscillation, imagine a cube of metal placed in an external electric field pointing to the right. Electrons will move to the left side (uncovering positive ions on the right side) until they cancel the field inside the metal. If the electric field is removed, the electrons move to the right, repelled by each other and attracted to the positive ions left bare on the right side. They oscillate back and forth at the plasma frequency until the energy is lost in some kind of resistance or damping. Plasmons are a quantization of this kind of oscillation.
Role
Plasmons play a huge role in the optical properties of metals and semiconductors. Frequencies of light below the plasma frequency are reflected by a material because the electrons in the material screen the electric field of the light. Light of frequencies above the plasma frequency is transmitted by a material because the electrons in the material cannot respond fast |
https://en.wikipedia.org/wiki/Sexual%20segregation%20%28biology%29 | In biology, sexual segregation is the differential use of space, habitats, and resources by males and females, or the separation of males and females into different social groups outside the breeding season. Sexual segregation is widespread among animals, especially among vertebrates that live in groups, and has also been observed in plants. It was first formally proposed by Charles Darwin in his book The Descent of Man, and Selection in Relation to Sex.
Definition
Sexual segregation has traditionally been defined as the differential use of space (spatial segregation) or habitat (habitat segregation) by males and females. Recently, it has also been defined as the separation of males and females into different social groups (social segregation) outside the breeding season. Some authors consider social segregation to be a by-product of habitat segregation but it is now known that social segregation can occur independently of habitat segregation. Conradt (2005) argued that spatial segregation should be treated as a auxiliary concept as both habitat segregation and social segregation can lead to spatial segregation. |
https://en.wikipedia.org/wiki/Do%20Not%20Track | Do Not Track (DNT) is a formerly official HTTP header field, designed to allow internet users to opt-out of tracking by websites—which includes the collection of data regarding a user's activity across multiple distinct contexts, and the retention, use, or sharing of data derived from that activity outside the context in which it occurred.
The Do Not Track header was originally proposed in 2009 by researchers Christopher Soghoian, Sid Stamm, and Dan Kaminsky. Mozilla Firefox became the first browser to implement the feature, while Internet Explorer, Apple's Safari, Opera and Google Chrome all later added support. Efforts to standardize Do Not Track by the W3C in the Tracking Preference Expression (DNT) Working Group reached only the Candidate Recommendation stage and ended in September 2018 due to insufficient deployment and support.
DNT is not widely adopted by the industry, with companies citing the lack of legal mandates for its use (see Do Not Track legislation), as well as unclear standards and guidelines for how websites are to interpret the header. Thus, critics purport that it is not guaranteed enabling DNT will actually have any effect at all. The W3C disbanded its DNT working group in January 2019, citing insufficient support and adoption. Apple discontinued support for DNT the following month, citing browser fingerprinting concerns. As of March 2023, Mozilla Firefox continues to support DNT, where it is turned on by default in private browsing mode and optional in regular mode.
In 2020, a coalition of US-based internet companies announced the Global Privacy Control header that spiritually succeeds Do Not Track header. The creators hope that this new header will meet the definition of "user-enabled global privacy controls" defined by the California Consumer Privacy Act (CCPA) and European General Data Protection Regulation (GDPR). In this case, the new header would be automatically strengthened by existing laws and companies would be required to honor i |
https://en.wikipedia.org/wiki/Flag%20of%20Cantabria | The flag of the Spanish region of Cantabria is made up of two horizontal stripes of equal width, white on the top and red on the bottom, and the region's coat of arms in its centre. The design is established in the text of the Autonomy Statute, except for the coat of arms, which was established by a Law of the Regional Assembly approved on 30 December 1981. The design traces its lineage to the ship registration flag of the maritime province of Santander, assigned by Royal Order on 30 July 1845.
In 2016, the Parliament of Cantabria also recognized the Cantabrian labarum as a symbol of the Cantabrian people, urging the institutions and civil society of Cantabria to promote its use. Most townships have already accepted the proposition of using said flag placing it on the balcony of the Town Hall.
Notes |
https://en.wikipedia.org/wiki/Common%20Crawl | Common Crawl is a nonprofit 501(c)(3) organization that crawls the web and freely provides its archives and datasets to the public. Common Crawl's web archive consists of petabytes of data collected since 2008. It completes crawls generally every month.
Common Crawl was founded by Gil Elbaz. Advisors to the non-profit include Peter Norvig and Joi Ito. The organization's crawlers respect nofollow and robots.txt policies. Open source code for processing Common Crawl's data set is publicly available.
The Common Crawl dataset includes copyrighted work and is distributed from the US under fair use claims. Researchers in other countries have made use of techniques such as shuffling sentences or referencing the common crawl dataset to work around copyright law in other legal jurisdictions.
As of March 2023, in the most recent version of the Common Crawl dataset, 46% of documents had English as their primary language (followed by German, Russian, Japanese, French, Spanish and Chinese, all below 6%).
History
Amazon Web Services began hosting Common Crawl's archive through its Public Data Sets program in 2012.
The organization began releasing metadata files and the text output of the crawlers alongside .arc files in July of that year. Common Crawl's archives had only included .arc files previously.
In December 2012, blekko donated to Common Crawl search engine metadata blekko gathered from crawls it conducted from February to October 2012. The donated data helped Common Crawl "improve its crawl while avoiding spam, porn and the influence of excessive SEO."
In 2013, Common Crawl began using Apache Software Foundation's Nutch webcrawler instead of a custom crawler. Common Crawl switched from using .arc files to .warc files with its November 2013 crawl.
A filtered version of Common Crawl was used to train OpenAI's GPT-3 language model, announced in 2020.
Timeline of Common Crawl data
The following data have been collected from the official Common Crawl Blog.
Norvig W |
https://en.wikipedia.org/wiki/Island%20growth | Island growth is a physical model of deposited film growth and chemical vapor deposition.
Introduction
When atoms are deposited slowly onto a flat surface, the first one undergoes a random walk on that surface. Eventually a second atom is deposited; in all likelihood it will eventually meet the first atom. Once the two atoms meet they may bond to form a particle with a higher mass and a lower random walk velocity. Because the bonded particles are now more stable and less mobile than before, they are called an "island." Subsequent atoms deposited on the substrate eventually meet and bond with the island, further increasing its size and stability. Eventually the island can grow to fill the entire substrate with a single large grain.
The faster the atoms are deposited, the greater amount of atoms on the substrate before any large stable islands form. As these atoms meet, they will bond to their local neighbors before having the chance to migrate to a distant island. In this way a large number of separate islands are formed and can grow independently. Eventually the separate islands will grow to become separate grains in the final film.
The island growth model is used to explain how fast deposition techniques (such as sputter deposition) can produce films with many randomly oriented grains, whereas slow deposition techniques (such as MBE) tend to produce larger grains with more uniform structure.
See also
Stranski–Krastanov growth |
https://en.wikipedia.org/wiki/Lasso%20%28statistics%29 | In statistics and machine learning, lasso (least absolute shrinkage and selection operator; also Lasso or LASSO) is a regression analysis method that performs both variable selection and regularization in order to enhance the prediction accuracy and interpretability of the resulting statistical model. It was originally introduced in geophysics, and later by Robert Tibshirani, who coined the term.
Lasso was originally formulated for linear regression models. This simple case reveals a substantial amount about the estimator. These include its relationship to ridge regression and best subset selection and the connections between lasso coefficient estimates and so-called soft thresholding. It also reveals that (like standard linear regression) the coefficient estimates do not need to be unique if covariates are collinear.
Though originally defined for linear regression, lasso regularization is easily extended to other statistical models including generalized linear models, generalized estimating equations, proportional hazards models, and M-estimators. Lasso's ability to perform subset selection relies on the form of the constraint and has a variety of interpretations including in terms of geometry, Bayesian statistics and convex analysis.
The LASSO is closely related to basis pursuit denoising.
History
Lasso was introduced in order to improve the prediction accuracy and interpretability of regression models. It selects a reduced set of the known covariates for use in a model.
Lasso was developed independently in geophysics literature in 1986, based on prior work that used the penalty for both fitting and penalization of the coefficients. Statistician Robert Tibshirani independently rediscovered and popularized it in 1996, based on Breiman's nonnegative garrote.
Prior to lasso, the most widely used method for choosing covariates was stepwise selection. That approach only improves prediction accuracy in certain cases, such as when only a few covariates have a str |
https://en.wikipedia.org/wiki/Carath%C3%A9odory%E2%80%93Jacobi%E2%80%93Lie%20theorem | The Carathéodory–Jacobi–Lie theorem is a theorem in symplectic geometry which generalizes Darboux's theorem.
Statement
Let M be a 2n-dimensional symplectic manifold with symplectic form ω. For p ∈ M and r ≤ n, let f1, f2, ..., fr be smooth functions defined on an open neighborhood V of p whose differentials are linearly independent at each point, or equivalently
where {fi, fj} = 0. (In other words, they are pairwise in involution.) Here {–,–} is the Poisson bracket. Then there are functions fr+1, ..., fn, g1, g2, ..., gn defined on an open neighborhood U ⊂ V of p such that (fi, gi) is a symplectic chart of M, i.e., ω is expressed on U as
Applications
As a direct application we have the following. Given a Hamiltonian system as where M is a symplectic manifold with symplectic form and H is the Hamiltonian function, around every point where there is a symplectic chart such that one of its coordinates is H. |
https://en.wikipedia.org/wiki/Tricentis%20Tosca | Tricentis Tosca is a software testing tool that is used to automate end-to-end testing for software applications. It is developed by Tricentis.
Tricentis Tosca combines multiple aspects of software testing (test case design, test automation, test data design and generation, and analytics) to test GUIs and APIs from a business perspective. Two of the most frequently-noted technologies used in Tricentis Tosca are related to Model-based testing and Risk-based testing.
Model-based testing
Instead of using scripting for test automation, Tricentis Tosca applies a model-based testing approach and creates a model of the application under test. Technical details about the application under test, test case logic, and test data are saved separately and joined together at test execution time. When an element in the application under test changes, the technical details are updated once in the central model. Since the test cases inherit from this model, the various test cases that test the updated element do not need to be modified manually to reflect the change.
Risk-based testing
Based on a risk assessment of the application under test’s requirements, Tricentis Tosca uses risk-based test design to suggest the most effective test cases and identify the risk contribution of each test cases. It also uses a variety of methodologies (such as equivalence partitioning, boundary testing, and combinatorial methods such as linear expansion) to try to minimize the number of test cases while increasing risk coverage. After the tests are executed, the tool aggregates risk coverage from business, technical, and compliance perspectives.
Additional technologies
Tricentis Tosca features technologies for GUI testing, API testing, Mobile testing, Service virtualization, Test data design and generation, Business intelligence and data warehouse testing, and Exploratory testing. It has SAP-certified integration with SAP solutions, and is used to automate testing for SAP technologies such as S |
https://en.wikipedia.org/wiki/Shrewd%20cardinal | In mathematics, a shrewd cardinal is a certain kind of large cardinal number introduced by , extending the definition of indescribable cardinals.
For an ordinal λ, a cardinal number κ is called λ-shrewd if for every proposition φ, and set A ⊆ Vκ with (Vκ+λ, ∈, A) ⊧ φ there exists an α, λ' < κ with (Vα+λ', ∈, A ∩ Vα) ⊧ φ. It is called shrewd if it is λ-shrewd for every λ(Definition 4.1) (including λ > κ).
This definition extends the concept of indescribability to transfinite levels. A λ-shrewd cardinal is also μ-shrewd for any ordinal μ < λ.(Corollary 4.3) Shrewdness was developed by Michael Rathjen as part of his ordinal analysis of Π12-comprehension. It is essentially the nonrecursive analog to the stability property for admissible ordinals.
More generally, a cardinal number κ is called λ-Πm-shrewd if for every Πm proposition φ, and set A ⊆ Vκ with (Vκ+λ, ∈, A) ⊧ φ there exists an α, λ' < κ with (Vα+λ', ∈, A ∩ Vα) ⊧ φ.(Definition 4.1) Πm is one of the levels of the Lévy hierarchy, in short one looks at formulas with m-1 alternations of quantifiers with the outermost quantifier being universal.
For finite n, an n-Πm-shrewd cardinals is the same thing as a Πmn-indescribable cardinal.
If κ is a subtle cardinal, then the set of κ-shrewd cardinals is stationary in κ.(Lemma 4.6) A cardinal is strongly unfoldable iff it is shrewd.
λ-shrewdness is an improved version of λ-indescribability, as defined in Drake; this cardinal property differs in that the reflected substructure must be (Vα+λ, ∈, A ∩ Vα), making it impossible for a cardinal κ to be κ-indescribable. Also, the monotonicity property is lost: a λ-indescribable cardinal may fail to be α-indescribable for some ordinal α < λ. |
https://en.wikipedia.org/wiki/Single-root%20input/output%20virtualization | In virtualization, single root input/output virtualization (SR-IOV) is a specification that allows the isolation of PCI Express resources for manageability and performance reasons.
Details
A single physical PCI Express bus can be shared in a virtual environment using the SR-IOV specification. The SR-IOV offers different virtual functions to different virtual components (e.g. network adapter) on a physical server machine. SR-IOV uses physical and virtual functions to control or configure PCIe devices. Physical functions have the ability to move data in and out of the device while virtual functions are lightweight PCIe functions that support data flowing but also have a restricted set of configuration resources. The virtual or physical functions available to the hypervisor or guest operating system depend on the PCIe device.
The SR-IOV allows different virtual machines (VMs) in a virtual environment to share a single PCI Express hardware interface. In contrast, MR-IOV allows I/O PCI Express to share resources among different VMs on different physical machines.
InfiniBand
A major field of application for SR-IOV is within the high-performance computing (HPC) field. The use of high-performance InfiniBand networking cards is growing within the HPC sector, and there is early research into the use of SR-IOV to allow for the use of InfiniBand within virtual machines such as Xen.
See also
I/O virtualization |
https://en.wikipedia.org/wiki/Phoebus%20Levene | Phoebus Aaron Theodore Levene (25 February 1869 – 6 September 1940) was a Russian-born American biochemist who studied the structure and function of nucleic acids. He characterized the different forms of nucleic acid, DNA from RNA, and found that DNA contained adenine, guanine, thymine, cytosine, deoxyribose, and a phosphate group.
He was born into a Litvak (Lithuanian Jewish) family as Fishel Rostropovich Levin in the town of Žagarė in Lithuania, then part of the Russian Empire, but grew up in St. Petersburg. There he studied medicine at the Imperial Military Medical Academy (M.D., 1891) and developed an interest in biochemistry. In 1893, because of anti-Semitic pogroms, he and his family emigrated to the United States and he practiced medicine in New York City.
Levene enrolled at Columbia University and in his spare time conducted biochemical research, publishing papers on the chemical structure of sugars. In 1896 he was appointed as an Associate in the Pathological Institute of the New York State Hospitals, but he had to take time off to recuperate from tuberculosis. During this period, he worked with several chemists, including Albrecht Kossel and Emil Fischer, who were the experts in proteins.
In 1905, Levene was appointed as head of the biochemical laboratory at the Rockefeller Institute of Medical Research. He spent the rest of his career at this institute, and it was there that he identified the components of DNA. In 1909, Levene and Walter Jacobs recognised -ribose as a natural product and an essential component of nucleic acids. They also recognised that the unnatural sugar that Emil Fischer and Oscar Piloty had reported in 1891 was the enantiomer of -ribose. Levene went on to discover deoxyribose in 1929. Not only did Levene identify the components of DNA, he also showed that the components were linked together in the order phosphate-sugar-base to form units. He called each of these units a nucleotide, and stated that the DNA molecule consiste |
https://en.wikipedia.org/wiki/Cross-buy | Cross-buy is a feature of some digital distribution systems available across multiple device platforms, where users who purchase a license to a specific piece of software are able to use the versions of the software for different device classes at no additional charge.
The term is associated mainly with digital distribution in video games, where cross-buy can span between a video game console and handheld game console, or between a console and a personal computer.
Examples
Sony Interactive Entertainment introduced cross-buy on PlayStation gaming platforms in August 2012: users who purchased select PlayStation 3 titles would be able to obtain ports for the portable PlayStation Vita console at no additional charge. The initiative was later extended to include PlayStation 4 and PlayStation 5.
Microsoft unveiled a similar scheme Xbox Play Anywhere in 2016, which is applicable to digital purchases of games on Microsoft Store across Windows 10, Xbox One, and Xbox Series X/S attached to the same account. This also includes synchronization of content, such as saves and achievements between all platforms. This arrangement is primarily used on first-party titles, but Resident Evil 7: Biohazard became the first third-party title to support Play Anywhere.
Oculus has a similar concept of cross-buy for Virtual Reality (VR) experiences bought on the Oculus PC VR platform for the Rift and Rift S headsets. PC VR Experiences which have subsequently appeared for the mobile virtual reality headsets Quest and Quest 2 can be made available to Quest/Quest 2 consumers without having to be bought a second time; however, the decision to support cross-buy lies with the game developers.
See also
Digital Copy, a similar concept for films. |
https://en.wikipedia.org/wiki/Heath-Brown%E2%80%93Moroz%20constant | The Heath-Brown–Moroz constant C, named for Roger Heath-Brown and Boris Moroz, is defined as
where p runs over the primes.
Application
This constant is part of an asymptotic estimate for the distribution of rational points of bounded height on the cubic surface X03=X1X2X3. Let H be a positive real number and N(H) the number of solutions to the equation X03=X1X2X3 with all the Xi non-negative integers less than or equal to H and their greatest common divisor equal to 1. Then |
https://en.wikipedia.org/wiki/Biofilm | A biofilm comprises any syntrophic consortium of microorganisms in which cells stick to each other and often also to a surface. These adherent cells become embedded within a slimy extracellular matrix that is composed of extracellular polymeric substances (EPSs). The cells within the biofilm produce the EPS components, which are typically a polymeric conglomeration of extracellular polysaccharides, proteins, lipids and DNA. Because they have three-dimensional structure and represent a community lifestyle for microorganisms, they have been metaphorically described as "cities for microbes".
Biofilms may form on living (biotic) or non-living (abiotic) surfaces and can be prevalent in natural, industrial, and hospital settings. They may constitute a microbiome or be a portion of it. The microbial cells growing in a biofilm are physiologically distinct from planktonic cells of the same organism, which, by contrast, are single cells that may float or swim in a liquid medium. Biofilms can form on the teeth of most animals as dental plaque, where they may cause tooth decay and gum disease.
Microbes form a biofilm in response to a number of different factors, which may include cellular recognition of specific or non-specific attachment sites on a surface, nutritional cues, or in some cases, by exposure of planktonic cells to sub-inhibitory concentrations of antibiotics. A cell that switches to the biofilm mode of growth undergoes a phenotypic shift in behavior in which large suites of genes are differentially regulated.
A biofilm may also be considered a hydrogel, which is a complex polymer that contains many times its dry weight in water. Biofilms are not just bacterial slime layers but biological systems; the bacteria organize themselves into a coordinated functional community. Biofilms can attach to a surface such as a tooth or rock, and may include a single species or a diverse group of microorganisms. Subpopulations of cells within the biofilm differentiate to perfor |
https://en.wikipedia.org/wiki/Circular%20dependency | In software engineering, a circular dependency is a relation between two or more modules which either directly or indirectly depend on each other to function properly. Such modules are also known as mutually recursive.
Overview
Circular dependencies are natural in many domain models where certain objects of the same domain depend on each other. However, in software design, circular dependencies between larger software modules are considered an anti-pattern because of their negative effects. Despite this, such circular (or cyclic) dependencies have been found to be widespread among the source files of real-world software. Mutually recursive modules are, however, somewhat common in functional programming, where inductive and recursive definitions are often encouraged.
Problems
Circular dependencies can cause many unwanted effects in software programs. Most problematic from a software design point of view is the tight coupling of the mutually dependent modules which reduces or makes impossible the separate re-use of a single module.
Circular dependencies can cause a domino effect when a small local change in one module spreads into other modules and has unwanted global effects (program errors, compile errors). Circular dependencies can also result in infinite recursions or other unexpected failures.
Circular dependencies may also cause memory leaks by preventing certain automatic garbage collectors (those that use reference counting) from deallocating unused objects.
Causes and solutions
In very large software designs, software engineers may lose the context and inadvertently introduce circular dependencies. There are tools to analyze software and find unwanted circular dependencies.
Circular dependencies can be introduced when implementing callback functionality. This can be avoided by applying design patterns like the observer pattern.
See also
Acyclic dependencies principle
Dependency hell |
https://en.wikipedia.org/wiki/Nerve%20to%20the%20stapedius | The nerve to the stapedius is a branch of the facial nerve (CN VII) which innervates the stapedius muscle. It arises from the CN VII within the facial canal, opposite the pyramidal eminence. It passes through a small canal in this eminence to reach the stapedius muscle. |
https://en.wikipedia.org/wiki/Kaldor%E2%80%93Hicks%20efficiency | A Kaldor–Hicks improvement, named for Nicholas Kaldor and John Hicks, is an economic re-allocation of resources among people that captures some of the intuitive appeal of a Pareto improvement, but has less stringent criteria and is hence applicable to more circumstances. A re-allocation is a Kaldor–Hicks improvement if those that are made better off could hypothetically compensate those that are made worse off and lead to a Pareto-improving outcome. The compensation does not actually have to occur (there is no presumption in favor of status-quo) and thus, a Kaldor–Hicks improvement can in fact leave some people worse off.
A situation is said to be Kaldor–Hicks efficient, or equivalently is said to satisfy the Kaldor–Hicks criterion, if no potential Kaldor–Hicks improvement from that situation exists. If an outcome is the highest it could possibly be, it is called a Hicks-optimal outcome. A Hicks optimal outcome is always Pareto efficient.
Explanation
A reallocation is said to be a Pareto improvement if at least one person is made better off and nobody is made worse off. However, in practice, it is almost impossible to take any social action, such as a change in economic policy, without making at least one person worse off. Even voluntary exchanges may not be Pareto improving if they make third parties worse off.
Using the criterion for Kaldor–Hicks improvement, an outcome is an improvement if those that are made better off could in principle compensate those that are made worse off, so that a Pareto improving outcome could (though does not have to) be achieved. For example, a voluntary exchange that creates pollution would be a Kaldor–Hicks improvement if the buyers and sellers are still willing to carry out the transaction even if they have to fully compensate the victims of the pollution. Kaldor–Hicks does not require compensation actually be paid, merely that the possibility for compensation exists, and thus need not leave each at least as well off. Under Kald |
https://en.wikipedia.org/wiki/Rational%20thermodynamics | Rational thermodynamics is a school of thought in statistical thermodynamics developed in the 1960s.
Its introduction is attributed to Clifford Truesdell (1919–2000), Bernard Coleman (b. 1929) and Walter Noll (1925–2017).
The aim was to develop a mathematical model of thermodynamics that would go beyond the traditional "thermodynamics of irreversible processes" or TIP developed in the late 19th to early 20th centuries.
Truesdell's "flamboyant style" and "satirical verve" caused controversy between "rational thermodynamics" and proponents of traditional thermodynamics. |
https://en.wikipedia.org/wiki/Miron%20Nicolescu | Miron Nicolescu (; August 27, 1903 – June 30, 1975) was a Romanian mathematician, best known for his work in real analysis and differential equations. He was President of the Romanian Academy and Vice-President of the International Mathematical Union.
Born in Giurgiu, the son of a teacher, he attended the Matei Basarab High School in Bucharest. After completing his undergraduate studies at the Faculty of Mathematics of the University of Bucharest in 1924, he went to Paris, where he enrolled at the École Normale Supérieure and the Sorbonne. In 1928, he completed his doctoral dissertation, Fonctions complexes dans le plan et dans l'espace, under the direction of Paul Montel. Upon returning to Romania, he taught at the University of Cernăuți until 1940, when he was named professor at the University of Bucharest.
In 1936, he was elected an associate member of the Romanian Academy, and, in 1953, full member. After King Michael's Coup of August 23, 1944, Nicolescu joined the Social Democratic Party, and later became a member of the Romanian Communist Party. In 1963, he became director of the Institute of Mathematics of the Romanian Academy, a position he held until 1973. From 1966 until his death, he served as President of the Romanian Academy. Peter Freund (who met Nicolescu when he gave a lecture in Timișoara), described him as an "affable, debonair man, and a very handsome ladies' man."
Nicolescu was awarded the Legion of Honour, Commander rank, and was elected in 1972 member of the German National Academy of Sciences Leopoldina. At the International Congress of Mathematicians held in Vancouver, British Columbia, Canada in 1974, he was elected Vice-President of the International Mathematical Union, a position he held from 1975 until his death (his term was completed by Gheorghe Vrănceanu).
A technical high school in Sector 4 of Bucharest bears his name, and so does a boulevard in Giurgiu.
Publications
See also
Heat equation |
https://en.wikipedia.org/wiki/Food%20coloring | Food coloring, or color additive, is any dye, pigment, or substance that imparts color when it is added to food or drink. They can be supplied as liquids, powders, gels, or pastes. Food coloring is used in both commercial food production and domestic cooking. Food colorants are also used in a variety of non-food applications, including cosmetics, pharmaceuticals, home craft projects, and medical devices. Colorings may be natural (e.g. anthocyanins, cochineal) or artificial/synthetic (e.g. tartrazine yellow).
Purpose of food coloring
People associate certain colors with certain flavors, and the color of food can influence the perceived flavor in anything from candy to wine. Sometimes, the aim is to simulate a color that is perceived by the consumer as natural, such as adding red coloring to glacé cherries (which would otherwise be beige), but sometimes it is for effect, like the green ketchup that Heinz launched in 2000. Color additives are used in foods for many reasons including:
To make food more attractive, appealing, appetizing, and informative
Offseting color loss over time due to exposure to light, air, temperature extremes, moisture and storage conditions
Correcting natural variations in color
Enhancing colors that occur naturally
Providing color to colorless and "fun" foods
Allowing products to be identified on sight, like candy flavors or medicine dosages
Natural food dyes
History
The addition of colorants to foods is thought to have occurred in Egyptian cities as early as 1500 BC, when candy makers added natural extracts and wine to improve the products' appearance. During the Middle Ages, the economy in the European countries was based on agriculture, and the peasants were accustomed to producing their own food locally or trading within the village communities. Under feudalism, aesthetic aspects were not considered, at least not by the vast majority of the generally very poor population. This situation changed with urbanization at the beginning |
https://en.wikipedia.org/wiki/Press%20cake | A press cake or oil cake is the solids remaining after pressing something to extract the liquids. Their most common use is in animal feed.
Some foods whose processing creates press cakes are olives for olive oil (pomace), peanuts for peanut oil, coconut flesh for coconut cream and milk (sapal), grapes for wine (pomace), apples for cider (pomace), mustard cake, and soybeans for soy milk (used to make tofu) (this is called soy pulp) or oil. Other common press cakes come from flax seed (linseed), cottonseed, and sunflower seeds. However, some specific kinds may be toxic, and are rather used as fertilizer, for example cottonseed contains a toxic pigment, gossypol, that must be removed before processing.
Culinary use
In Nepalese cuisine the oil cake of the Persian walnut is used for culinary purposes, and it is also applied to the forehead to treat headaches. In some regions it is used as boiler fuel as a means of reducing energy costs, for which it is quite suitable.
Military use
In 1942 the Porton Down biology department outsourced the production of 5,273,400 linseed press cakes to Olympia Oil and Cake Company in Blackburn Meadows which would then be infected with Bacillus anthracis (bacteria that causes Anthrax) and using in the biological warfare program Operation Vegetarian. |
https://en.wikipedia.org/wiki/IEEE%20802.1ah | IEEE 802.1ah is an amendment to the IEEE 802.1Q networking standard which adds support for Provider Backbone Bridges. It includes an architecture and a set of protocols for routing over a provider's network, allowing interconnection of multiple provider bridge networks without losing each customer's individually defined VLANs. It was initially created by Nortel before being submitted to the IEEE 802.1 committee for standardization. The final version was approved by the IEEE in June 2008 and has been integrated into IEEE 802.1Q-2011.
History
The now-ubiquitous Ethernet was initially defined as a local area network (LAN) technology to interconnect the computers within a small organization in which these host computers were very close in proximity to each other. Over the years, Ethernet has become such a popular technology that it became the default Data Link Layer (OSI Layer 2) mechanism for data transport. This created a need for extending the Ethernet from a customer LAN bridging domain to service provider MAN, also known as the Provider bridging domain. For this, a 4 byte S-Tag or Service Tag, a type of Virtual LAN tag, was added to the header of the Ethernet frame in IEEE 802.1ad standard. In the service provider domain, switching was based on S-Tag and destination MAC address, and C-tag was used to create virtual LAN within the customer domain. This technology is also known as QinQ or Q-tunneling.
QinQ does not offer true separation of customer and provider domains but is merely a way to overcome the limitations on the VLAN identifier space. It can also help in separation of the customer and provider control domains when used with other features like control protocol tunneling or Per-VLAN Spanning Tree etc. There is still the problem of having too little control on the MAC addresses, since QinQ forwarding is still based on the customer destination addresses. Thus, better mechanisms are needed.
Description
The idea of PBB is to offer complete separation of c |
https://en.wikipedia.org/wiki/Acyl%20carrier%20protein | The acyl carrier protein (ACP) is a cofactor of both fatty acid and polyketide biosynthesis machinery. It is one of the most abundant proteins in cells of E. coli. In both cases, the growing chain is bound to the ACP via a thioester derived from the distal thiol of a 4'-phosphopantetheine moiety.
Structure
The ACPs are small negatively charged α-helical bundle proteins with a high degree of structural and amino acid similarity. The structures of a number of acyl carrier proteins have been solved using various NMR and crystallography techniques. The ACPs are related in structure and mechanism to the peptidyl carrier proteins (PCP) from nonribosomal peptide synthases.
Biosynthesis
Subsequent to the expression of the inactive apo ACP, the 4'-phosphopantetheine moiety is attached to a serine residue. This coupling is mediated by acyl carrier protein synthase (ACPS), a 4'-phosphopantetheinyl transferase. 4'-Phosphopantetheine is a prosthetic group of several acyl carrier proteins including the acyl carrier proteins (ACP) of fatty acid synthases, ACPs of polyketide synthases, the peptidyl carrier proteins (PCP), as well as aryl carrier proteins (ArCP) of nonribosomal peptide synthetases (NRPS). |
https://en.wikipedia.org/wiki/Cold-stunning | Cold-stunning, also known as hypothermic stunning, is a hypothermic reaction experienced by marine reptiles, notably sea turtles, when exposed to cold water for prolonged periods, which causes them to become weak and inactive. Cold-stunned sea turtles may float to the surface and be further exposed to cold temperatures, which can cause them to drown. A water temperature threshold of 8–10 °C has been associated with mass turtle stunning events. After cold-stunning has taken place, there is only a very short period of time when sea turtles can be safely rescued.
One study indicates that ocean warming has led to an increase in cold-stunning events in the northwest Atlantic.
Notable instances
In 2016, 1,700 turtles were cold-stunned in North Carolina, following "an unusually temperate fall and early winter".
In 2021, nearly 5,000 cold-stunned turtles were rescued in Texas during a winter storm; it has been called the largest cold-stunning event to be documented in the state.
See also
Physiology of aquatic reptiles |
https://en.wikipedia.org/wiki/Silicone%20quaternary%20amine | Silicone quaternary amine is a chemical antimicrobial agent used in some odor-repellent socks, including Burlington Bioguard Socks.
External links
Antimicrobials
Polymers |
https://en.wikipedia.org/wiki/Hay%20lot | A Hay Lot is a portion of common land used for haymaking and assigned by lot or allotment. Traditionally a marker, usually of stone, was used in early agriculture to mark the position of an individual hay lot within a hay meadow. The marker stone would typically bear the initials of the lot-holder. Such markers would have been common-place in meadows in Britain, but with the advent of modern farming many hay meadows were ploughed for arable crops, and the hay lots removed. Today, few such examples remain, but some can be seen in the North Meadow at Cricklade.
In modern agriculture a Hay lot is defined as the harvest of hay from a single field undertaken within a 48-hour period. Depending upon the size of the field and the capacity of the harvesting equipment used, the amount of hay collected in this period can vary greatly, reaching up to .
See also
Earsh
Field
Flood-meadow
Grassland
Meadow
Pasture |
https://en.wikipedia.org/wiki/Fast%20Reroute | Fast Reroute is a MPLS (Multiprotocol Label Switching) and IP resiliency technology to provide fast traffic recovery upon link or router failures for mission critical services.
Upon any single link or node failures, it could be able to recover impacted traffic flows in the level of 50 ms. Industrial implementations can be seen in vendors such as Cisco, Juniper, Brocade, Alcatel-Lucent etc.
In the IP domain Loop-Free Alternates (LFAs) and not-via technology have been used to immediately recover data packet upon the failure of a default next-hop.
Methods of backup
Backup path can be configured for:
1. Link protection
2. Node protection
There are two methods to back up an LSP:
1. One to One - this method creates detour LSPs for each protected LSP at each potential point of local repair
2. Facility - this method creates a bypass tunnel to protect a potential failure point |
https://en.wikipedia.org/wiki/Delta-convergence | In mathematics, Delta-convergence, or Δ-convergence, is a mode of convergence in metric spaces, weaker than the usual metric convergence, and similar to (but distinct from) the weak convergence in Banach spaces. In Hilbert space, Delta-convergence and weak convergence coincide. For a general class of spaces, similarly to weak convergence, every bounded sequence has a Delta-convergent subsequence.
Delta convergence was first introduced by Teck-Cheong Lim, and, soon after, under the name of almost convergence, by Tadeusz Kuczumow.
Definition
A sequence in a metric space is said to be Δ-convergent to if for every , .
Characterization in Banach spaces
If is a uniformly convex and uniformly smooth Banach space, with the duality mapping given by , , then a sequence is Delta-convergent to if and only if converges to zero weakly in the dual space (see ). In particular, Delta-convergence and weak convergence coincide if is a Hilbert space.
Opial property
Coincidence of weak convergence and Delta-convergence is equivalent, for uniformly convex Banach spaces, to the well-known
Opial property
Delta-compactness theorem
The Delta-compactness theorem of T. C. Lim states that if is an asymptotically complete metric space, then every bounded sequence in has a Delta-convergent subsequence.
The Delta-compactness theorem is similar to the Banach–Alaoglu theorem for weak convergence but, unlike the Banach-Alaoglu theorem (in the non-separable case) its proof does not depend on the Axiom of Choice.
Asymptotic center and asymptotic completeness
An asymptotic center of a sequence , if it exists, is a limit of the Chebyshev centers for truncated sequences . A metric space is called asymptotically complete, if any bounded sequence in it has an asymptotic center.
Uniform convexity as sufficient condition of asymptotic completeness
Condition of asymptotic completeness in the Delta-compactness theorem is satisfied by uniformly convex Banach spaces, and more gen |
https://en.wikipedia.org/wiki/Code%20page%20942 | Code page 942 (abbreviated as CP942 or IBM-942) is one of IBM's extensions of Shift JIS. The coded character sets are JIS X 0201, JIS X 0208, IBM extensions for IBM 1880 UDC and IBM extensions. It is the combination of the single-byte Code page 1041 and the double-byte Code page 301.
It is a superset of IBM-932, differing in its use of Code page 1041 in place of Code page 897 for its single byte codes. Code page 1041 is an extension of Code page 897 and adds five single-byte characters. 0x80 is mapped to the cent sign (¢), 0xA0 is mapped to the pound sign (£), 0xFD is mapped to the not sign (¬), 0xFE is mapped to the backslash (\) and 0xFF is mapped to the tilde (~). These are all unassigned in Code page 897 and therefore IBM-932.
Code page 942 contains standard 7-bit ISO 646 codes, and Japanese characters are indicated by the high bit of the first byte being set to 1. Some code points in this page require a second byte, so characters use either 8 or 16 bits for encoding.
Code page 1041, and therefore Code page 942, uses 0x5C for the Yen sign (¥) and 0x7E for the overline (‾), matching the lower half of JIS X 0201 rather than US-ASCII. However, the version of Code page 942 used in International Components for Unicode (called "ibm-942_P12A-1999" or "x-IBM942C") uses US-ASCII mappings for single-byte characters between 0x20 and 0x7E. This results in duplicate mapping for the tilde (0x7E and 0xFF) and the backslash (0x5C and 0xFE).
Layout
See also
Code page 943 |
https://en.wikipedia.org/wiki/Gautschi%27s%20inequality | In real analysis, a branch of mathematics, Gautschi's inequality is an inequality for ratios of gamma functions. It is named after Walter Gautschi.
Statement
Let be a positive real number, and let . Then
History
In 1948, Wendel proved the inequalities
for and . He used this to determine the asymptotic behavior of a ratio of gamma functions. The upper bound in this inequality is stronger than the one given above.
In 1959, Gautschi independently proved two inequalities for ratios of gamma functions. His lower bounds were identical to Wendel's. One of his upper bounds was the one given in the statement above, while the other one was sometimes stronger and sometimes weaker than Wendel's.
Consequences
An immediate consequence is the following description of the asymptotic behavior of ratios of gamma functions:
Proofs
There are several known proofs of Gautschi's inequality. One simple proof is based on the strict logarithmic convexity of Euler's gamma function. By definition, this means that for every and with and every , we have
Apply this inequality with , , and . Also apply it with , , and . The resulting inequalities are:
Rearranging the first of these gives the lower bound, while rearranging the second and applying the trivial estimate gives the upper bound.
Related inequalities
A survey of inequalities for ratios of gamma functions was written by Qi.
The proof by logarithmic convexity gives the stronger upper bound
Gautschi's original paper proved a different stronger upper bound,
where is the digamma function. Neither of these upper bounds is always stronger than the other.
Kershaw proved two tighter inequalities. Again assuming that and ,
Gautschi's inequality is specific to a quotient of gamma functions evaluated at two real numbers having a small difference. However, there are extensions to other situations. If and are positive real numbers, then the convexity of leads to the inequality:
For , this leads to the estimates
|
https://en.wikipedia.org/wiki/IEEE%20802.1ag | IEEE 802.1ag is an amendment to the IEEE 802.1Q networking standard which introduces Connectivity Fault Management (CFM). This defines protocols and practices for the operations, administration, and maintenance (OAM) of paths through 802.1 bridges and local area networks (LANs). The final version was approved by the IEEE in 2007.
IEEE 802.1ag is a subset of the earlier ITU-T Recommendation Y.1731, which additionally addresses performance monitoring.
The standard:
Defines maintenance domains, their constituent maintenance points, and the managed objects required to create and administrate them
Defines the relationship between maintenance domains and the services offered by VLAN-aware bridges and provider bridges
Describes the protocols and procedures used by maintenance points to maintain and diagnose connectivity faults within a maintenance domain;
Provides means for future expansion of the capabilities of maintenance points and their protocols
Definitions
The document defines various terms:
Maintenance Domain (MD) Maintenance Domains are management space on a network, typically owned and operated by a single entity. MDs are configured with Names and Levels, where the eight levels range from 0 to 7. A hierarchical relationship exists between domains based on levels. The larger the domain, the higher the level value. Recommended values of levels are as follows:
Customer Domain: Largest (e.g., 7)
Provider Domain: In between (e.g., 3)
Operator Domain: Smallest (e.g., 1)
Maintenance Association (MA) Defined as a "set of MEPs, all of which are configured with the same MAID (Maintenance Association Identifier) and MD Level, each of which is configured with a MEPID unique within that MAID and MD Level, and all of which are configured with the complete list of MEPIDs."
Maintenance association End Point (MEP) Points at the edge of the domain, define the boundary for the domain. A MEP sends and receives CFM frames through the relay function, drops all CFM frames of its |
https://en.wikipedia.org/wiki/Synchronous%20frame | A synchronous frame is a reference frame in which the time coordinate defines proper time for all co-moving observers. It is built by choosing some constant time hypersurface as an origin, such that has in every point a normal along the time line and a light cone with an apex in that point can be constructed; all interval elements on this hypersurface are space-like. A family of geodesics normal to this hypersurface are drawn and defined as the time coordinates with a beginning at the hypersurface. In terms of metric-tensor components , a synchronous frame is defined such that
where Such a construct, and hence, choice of synchronous frame, is always possible though it is not unique. It allows any transformation of space coordinates that does not depend on time and, additionally, a transformation brought about by the arbitrary choice of hypersurface used for this geometric construct.
Synchronization in an arbitrary frame of reference
Synchronization of clocks located at different space points means that events happening at different places can be measured as simultaneous if those clocks show the same times. In special relativity, the space distance element dl is defined as the intervals between two very close events that occur at the same moment of time. In general relativity this cannot be done, that is, one cannot define dl by just substituting dt ≡ dx0 = 0 in the metric. The reason for this is the different dependence between proper time and time coordinate x0 ≡ t in different points of space., i.e.,
To find dl in this case, time can be synchronized over two infinitesimally neighboring points in the following way (Fig. 1): Bob sends a light signal from some space point B with coordinates to Alice who is at a very close point A with coordinates xα and then Alice immediately reflects the signal back to Bob. The time necessary for this operation (measured by Bob), multiplied by c is, obviously, the doubled distance between Alice and Bob.
The line eleme |
https://en.wikipedia.org/wiki/Protocol%20Wars | A long-running debate in computer science known as the Protocol Wars occurred from the 1970s to the 1990s when engineers, organizations and nations became polarized over the issue of which communication protocol would result in the best and most robust computer networks. This culminated in the Internet–OSI Standards War in the 1980s and early 1990s, which was ultimately "won" by the Internet protocol suite (TCP/IP) by the mid-1990s and has since resulted in most other protocols disappearing.
The pioneers of packet switching technology built computer networks to research and provide data communications in the late 1960s and early 1970s. As more networks emerged in the mid to late 1970s, the debate about interface standards was described as a "battle for access standards". An international collaboration between several national postal, telegraph and telephone (PTT) providers and commercial operators agreed to the X.25 standard in 1976, which was adopted on public data networks providing global coverage. Separately, proprietary data communication protocols also emerged, most notably IBM's Systems Network Architecture and Digital Equipment Corporation's DECnet.
The United States Department of Defense developed and tested TCP/IP during the 1970s in collaboration with universities and researchers in the United States, United Kingdom and France. IPv4 was released in 1981 and the DoD made it standard for all military computer networking. By 1984, an international reference model known as the OSI model had been agreed upon, with which TCP/IP was not compatible. Many governments in Europe – particularly France, West Germany, the United Kingdom and the European Economic Community – and also the United States Department of Commerce mandated compliance with the OSI model and the US Department of Defense planned to transition away from TCP/IP to OSI.
Meanwhile, the development of a complete Internet protocol suite by 1989, and partnerships with the telecommunication and comput |
https://en.wikipedia.org/wiki/Entner%E2%80%93Doudoroff%20pathway | The Entner–Doudoroff pathway (ED Pathway) is a metabolic pathway that is most notable in Gram-negative bacteria, certain Gram-positive bacteria and archaea. Glucose is the substrate in the ED pathway and through a series of enzyme assisted chemical reactions it is catabolized into pyruvate. Entner and Doudoroff (1952) and MacGee and Doudoroff (1954) first reported the ED pathway in the bacterium Pseudomonas saccharophila. While originally thought to be just an alternative to glycolysis (EMP) and the pentose phosphate pathway (PPP), some studies now suggest that the original role of the EMP may have originally been about anabolism and repurposed over time to catabolism, meaning the ED pathway may be the older pathway. Recent studies have also shown the prevalence of the ED pathway may be more widespread than first predicted with evidence supporting the presence of the pathway in cyanobacteria, ferns, algae, mosses, and plants. Specifically, there is direct evidence that Hordeum vulgare uses the Entner–Doudoroff pathway.
Distinct features of the Entner–Doudoroff pathway are that it:
Uses the unique enzymes 6-phosphogluconate dehydratase aldolase and 2-keto-deoxy-6-phosphogluconate (KDPG) aldolase and other common metabolic enzymes to other metabolic pathways to catabolize glucose to pyruvate.
In the process of breaking down glucose, a net yield of 1 ATP is formed per every one glucose molecule processed, as well as 1 NADH and 1 NADPH. In comparison, glycolysis has a net yield of 2 ATP molecules and 2 NADH molecules per every one glucose molecule metabolized. This difference in energy production may be offset by the difference in protein amount needed per pathway.
Archaeal variations
Archaea have variants of the Entner-Doudoroff Pathway. These variants are called the semiphosphorylative ED (spED) and the nonphosphorylative ED (npED):
spED is found in halophilic euryachaea and Clostridium species.
In spED, the difference is where phosphorylation occurs. In the |
https://en.wikipedia.org/wiki/Wireless%20mobility%20management | Wireless mobility management in Personal Communications Service (PCS) is the assigning and controlling of wireless links for terminal network connections. Wireless mobility management provides an "alerting" function for call completion to a wireless terminal, monitors wireless link performance to determine when an automatic link transfer is required, and coordinates link transfers between wireless access interfaces.
One use of this is wireless push technology, by pushing data across wireless networks, this coordinates the link transfers and pushes data between the backend and wireless device only when an established connection is found. |
https://en.wikipedia.org/wiki/Gamma%20matrices | In mathematical physics, the gamma matrices, also called the Dirac matrices, are a set of conventional matrices with specific anticommutation relations that ensure they generate a matrix representation of the Clifford algebra It is also possible to define higher-dimensional gamma matrices. When interpreted as the matrices of the action of a set of orthogonal basis vectors for contravariant vectors in Minkowski space, the column vectors on which the matrices act become a space of spinors, on which the Clifford algebra of spacetime acts. This in turn makes it possible to represent infinitesimal spatial rotations and Lorentz boosts. Spinors facilitate spacetime computations in general, and in particular are fundamental to the Dirac equation for relativistic particles.
In Dirac representation, the four contravariant gamma matrices are
is the time-like, Hermitian matrix. The other three are space-like, anti-Hermitian matrices. More compactly, and where denotes the Kronecker product and the (for ) denote the Pauli matrices.
In addition, for discussions of group theory the identity matrix () is sometimes included with the four gamma matricies, and there is an auxiliary, "fifth" traceless matrix used in conjunction with the regular gamma matrixies
The "fifth matrix" is not a proper member of the main set of four; it used for separating nominal left and right chiral representations.
The gamma matrices have a group structure, the gamma group, that is shared by all matrix representations of the group, in any dimension, for any signature of the metric. For example, the 2×2 Pauli matrices are a set of "gamma" matrices in three dimensional space with metric of Euclidean signature (3, 0). In five spacetime dimensions, the four gammas, above, together with the fifth gamma-matrix to be presented below generate the Clifford algebra.
Mathematical structure
The defining property for the gamma matrices to generate a Clifford algebra is the anticommutation relation
wher |
https://en.wikipedia.org/wiki/Mostow%E2%80%93Palais%20theorem | In mathematics, the Mostow–Palais theorem is an equivariant version of the Whitney embedding theorem. It states that if a manifold is acted on by a compact Lie group with finitely many orbit types, then it can be embedded into some finite-dimensional orthogonal representation. It was introduced by and . |
https://en.wikipedia.org/wiki/Sandy%20Bridge | Sandy Bridge is the codename for Intel's 32 nm microarchitecture used in the second generation of the Intel Core processors (Core i7, i5, i3). The Sandy Bridge microarchitecture is the successor to Nehalem and Westmere microarchitecture. Intel demonstrated a Sandy Bridge processor in 2009, and released first products based on the architecture in January 2011 under the Core brand.
Sandy Bridge is manufactured in the 32 nm process and has a soldered contact with the die and IHS (Integrated Heat Spreader), while Intel's subsequent generation Ivy Bridge uses a 22 nm die shrink and a TIM (Thermal Interface Material) between the die and the IHS.
Technology
Intel demonstrated a Sandy Bridge processor with A1 stepping at 2 GHz during the Intel Developer Forum in September 2009.
Upgraded features from Nehalem include:
CPU
Intel Turbo Boost 2.0
32 KB data + 32 KB instruction L1 cache and 256 KB L2 cache per core
Shared L3 cache which includes the processor graphics (LGA 1155)
64-byte cache line size
New µOP cache, up to 1536-entry
Improved 3 integer ALU, 2 vector ALU and 2 AGU per core
Two load/store operations per CPU cycle for each memory channel
Decoded micro-operation cache, and enlarged, optimized branch predictor
Sandy Bridge retains the four branch predictors found in Nehalem: the branch target buffer (BTB), indirect branch target array, loop detector and renamed return stack buffer (RSB). Sandy Bridge has a single BTB that holds twice as many branch targets as the L1 and L2 BTBs in Nehalem.
Improved performance for transcendental mathematics, AES encryption (AES instruction set), and SHA-1 hashing
256-bit/cycle ring bus interconnect between cores, graphics, cache and System Agent Domain
Advanced Vector Extensions (AVX) 256-bit instruction set with wider vectors, new extensible syntax and rich functionality
Up to 8 physical cores, or 16 logical cores through hyper-threading (From 6 core/12 thread)
Integration of the GMCH (integrated graphics and memo |
https://en.wikipedia.org/wiki/Multiply%20transitive%20group%20action | A group acts 2-transitively on a set if it acts transitively on the set of distinct ordered pairs . That is, assuming (without a real loss of generality) that acts on the left of , for each pair of pairs with and , there exists a such that .
The group action is sharply 2-transitive if such is unique.
A 2-transitive group is a group such that there exists a group action that's 2-transitive and faithful. Similarly we can define sharply 2-transitive group.
Equivalently, and , since the induced action on the distinct set of pairs is .
The definition works in general with k replacing 2. Such multiply transitive permutation groups can be defined for any natural number k. Specifically, a permutation group G acting on n points is k-transitive if, given two sets of points a1, ... ak and b1, ... bk with the property that all the ai are distinct and all the bi are distinct, there is a group element g in G which maps ai to bi for each i between 1 and k. The Mathieu groups are important examples.
Examples
Every group is trivially 1-transitive, by its action on itself by left-multiplication.
Let be the symmetric group acting on , then the action is sharply n-transitive.
The group of n-dimensional homothety-translations acts 2-transitively on .
The group of n-dimensional projective transforms almost acts sharply (n+2)-transitively on the n-dimensional real projective space . The almost is because the (n+2) points must be in general linear position. In other words, the n-dimensional projective transforms act transitively on the space of projective frames of .
Classifications of 2-transitive groups
Every 2-transitive group is a primitive group, but not conversely. Every Zassenhaus group is 2-transitive, but not conversely. The solvable 2-transitive groups were classified by Bertram Huppert and are described in the list of transitive finite linear groups. The insoluble groups were classified by using the classification of finite simple groups and are all almo |
https://en.wikipedia.org/wiki/Petroleum%20microbiology | Petroleum microbiology is a branch of microbiology that deals with the study of microorganisms that can metabolize or alter crude or refined petroleum products. These microorganisms, also called hydrocarbonoclastic microorganisms, can degrade hydrocarbons and, include a wide distribution of bacteria, methanogenic archaea, and some fungi. Not all hydrocarbonoclasic microbes depend on hydrocarbons to survive, but instead may use petroleum products as alternative carbon and energy sources. Interest in this field is growing due to the increasing use of bioremediation of oil spills.
Applications
Bioremediation
Bioremediation of oil contaminated soils, marine waters and oily sludges in situ is a feasible process as hydrocarbon degrading microorganisms are ubiquitous and are able to degrade most compounds in petroleum oil. In the simplest case, indigenous microbial communities can degrade the petroleum where the spill occurs. In more complicated cases, various methods of adding nutrients, air, or exogenous microorganisms to the contaminated site can be applied. For example, bioreactors involve the application of both natural and additional microorganisms in controlled growth conditions that yields high biodegradation rates and can be used with a wide range of media.
Crude oils are composed of an array of chemical compounds, minor constituents, and trace metals. Making up 50-98% of these petroleum products are hydrocarbons with saturated, unsaturated, or aromatic structures which influence their biodegradability by hydronocarbonclasts. The rate of uptake and biodegradation by these hydrocarbon-oxidizing microbes not only depend on the chemical structure of the substrates, but is limited by biotic and abiotic factors such as temperature, salinity, and nutrient availability in the environment.
Alcanivorax borkumensis
A model microorganism studied for its role in bioremediation of oil-spill sites and hydrocarbon catabolism is the alpha-proteobacteria Alcanivorax, which d |
https://en.wikipedia.org/wiki/Map%20symbol | A map symbol or cartographic symbol is a graphical device used to visually represent a real-world feature on a map, working in the same fashion as other forms of symbols. Map symbols may include point markers, lines, regions, continuous fields, or text; these can be designed visually in their shape, size, color, pattern, and other graphic variables to represent a variety of information about each phenomenon being represented.
Map symbols simultaneously serve several purposes:
Declare the existence of geographic phenomena
Show location and extent
Visualize attribute information
Add to (or detract from) the aesthetic appeal of the map, and/or evoke a particular aesthetic reaction (a "look and feel")
Establish an overall gestalt order to make the map more or less useful, including visual hierarchy
Representing spatial phenomena
Symbols are used to represent geographic phenomena, which exist in, and are represented by, a variety of spatial forms. Different kinds of symbols are used to portray different spatial forms. Phenomena can be categorized a number of ways, but two are most relevant to symbology: ontological form and dimensionality. When a symbol is representing a property of the phenomenon as well as its location, the choice of symbol also depends on the nature of that property, usually classified as a Level of measurement.
Ontological form
Geographic phenomena can be categorized into objects, which are recognizable as a unified whole with a relevant boundary and shape; and masses, in which the notion of boundary and wholeness are not relevant to their identity. Features such as buildings, cities, roads, lakes, and countries are geographic objects that are often portrayed on maps using symbols. Mass phenomena include air, water, vegetation, and rock. These are rarely represented directly on maps; instead, map symbols portray their properties, which usually take the form of geographic fields, such as temperature, moisture content, density, and composition |
https://en.wikipedia.org/wiki/Creswell%20Crags | Creswell Crags is an enclosed limestone gorge on the border between Derbyshire and Nottinghamshire, England, near the villages of Creswell and Whitwell. The cliffs in the ravine contain several caves that were occupied during the last ice age, between around 43,000 and 10,000 years ago. Its caves contain the northernmost cave art in Europe. The evidence of occupation found in the rich series of sediments that accumulated over many thousands of years is regarded as internationally unique in demonstrating how prehistoric people managed to live at the extreme northernmost limits of their territory during the Late Pleistocene period.
The caves contain occupation layers with evidence of flint tools from the Mousterian, proto-Solutrean, Creswellian and Maglemosian cultures. They were seasonally occupied by nomadic groups of people during the Upper Palaeolithic and Mesolithic periods. Evidence of Neolithic, Bronze Age, Roman and post-medieval activity has also been found there. There is evidence of Neanderthal occupation 50,000–60,000 years ago, a brief Gravettian occupation around 32,000 years ago and use of all the main caves during the Magdalenian around 14,000 years ago. The site is open to the public and has a visitor centre with a small museum of objects associated with the caves, including a stuffed cave hyena.
As a result of its unique features, Creswell Crags has been designated as a Site of Special Scientific Interest (SSSI). It has also been put forward as a potential World Heritage Site.
In 2005–06, the B6042 road was re-routed from its path through the gorge, by approximately to the north, to minimise traffic impact on the site.
Neanderthal and Upper Palaeolithic occupation
Creswell Crags and Whitwell Gap
Before Creswell village was built around the colliery in the late 19th century, there were only farms around the entrance to the Crags. The local Anglo Saxon villages were Whitwell, Elmton and Thorpe (Salvin). Creswell was the name of the farm neares |
https://en.wikipedia.org/wiki/Ky%20Fan%20inequality%20%28game%20theory%29 | In mathematics, there are different results that share the common name of the Ky Fan inequality. The Ky Fan inequality presented here is used in game theory to investigate the existence of an equilibrium.
Another Ky Fan inequality is an inequality involving the geometric mean and arithmetic mean of two sets of real numbers of the unit interval.
Statement
Suppose that is a convex compact subset of a Hilbert space and that is a function from to satisfying
is lower semicontinuous for every and
is concave for every .
Then there exists such that |
https://en.wikipedia.org/wiki/International%20Congress%20of%20Genetics | The International Congress of Genetics (ICG) is a five yearly conference for geneticists. The first ICG was held in 1898. Since 1973 It has been organized by the International Genetics Federation (IGF). The aim of the congress is to reflect on progress made in genetics, to celebrate the best of contemporary research and to anticipate future developments in the discipline. It is one of the most important genetics meetings, presenting all subfields of the discipline. These subfields cover all present-day experiments using the powerful genomic technologies. Also, the benefits and wider implications of genetic research to societies at large are explored.
The Congress has been held in many major cities around the world, such as London, New York City, Paris, Ithaca, Edinburgh, Stockholm, Bellagio, Montreal, The Hague, Tokyo, Berkeley, Moscow, New Delhi, Toronto, Birmingham, Beijing, Melbourne, Berlin and Singapore.
The last International Congress of Genetics took place in Singapore in 2013. In 2018, the 22nd International Congress of Genetics will be held in Foz de Iguaçu, Brazil.
The International Genetics Federation (IGF) is an association of national genetics societies interested in promoting the advancement of the science of genetics. The IGF is governed by a representative council that meets every five years at the International Congress of Genetics (ICG) to choose the venue of the next Congress, to elect IGF officers and members of the Executive Board, and to set dues, make or affirm policy decisions, and amend the IGF Constitution as needed.
Meeting history
2023 - Melbourne, Australia (XXIII)
2018 - Foz do Iguaçu, Brazil (XXII)
2013 - Singapore (XXI)
2008 - Berlin, Germany (XX)
2003 - Melbourne, Australia (XIX)
1998 - Beijing, China (XVIII)
1993 - Birmingham, UK (XVII)
1988 - Toronto, Canada (XVI)
1983 - New Delhi, India (XV)
1978 - Moscow, USSR (XIV)
1973 - Berkeley, USA(XIII)
1968 - Tokyo, Japan (XII)
1963 - The Hague, The Netherlands (XI)
1958 |
https://en.wikipedia.org/wiki/Wireless%20access%20point | In computer networking, a wireless access point, or more generally just access point (AP), is a networking hardware device that allows other Wi-Fi devices to connect to a wired network. As a standalone device, the AP may have a wired connection to a router, but, in a wireless router, it can also be an integral component of the router itself. An AP is differentiated from a hotspot, which is a physical location where Wi-Fi access is available.
Although WAP has been used incorrectly to describe an Access Point, the clear definition is Wireless Application Protocol which describes a protocol rather than a physical device.
Connections
An AP connects directly to a wired local area network, typically Ethernet, and the AP then provides wireless connections using wireless LAN technology, typically Wi-Fi, for other devices to use that wired connection. APs support the connection of multiple wireless devices through their one wired connection.
Wireless data standards
There are many wireless data standards that have been introduced for wireless access point and wireless router technology. New standards have been created to accommodate the increasing need for faster wireless connections. Some wireless routers provide backward compatibility with older Wi-Fi technologies as many devices were manufactured for use with older standards.
802.11a
802.11b
802.11g
802.11n (Wi-Fi 4)
802.11ac (Wi-Fi 5)
802.11ax, (Wi-Fi 6)
Wireless access point vs. ad hoc network
Some people confuse wireless access points with wireless ad hoc networks. An ad hoc network uses a connection between two or more devices without using a wireless access point; The devices communicate directly when in range. Because setup is easy and does not require an access point, an ad hoc network is used in situations such as a quick data exchange or a multiplayer video game. Due to its peer-to-peer layout, ad hoc Wi-Fi connections are similar to connections available using Bluetooth.
Ad hoc connections are gener |
https://en.wikipedia.org/wiki/Insufflation%20%28medicine%29 | Insufflation () is the act of blowing something (such as a gas, powder, or vapor) into a body cavity. Insufflation has many medical uses, most notably as a route of administration for various drugs.
Medical uses
Surgery
Gases are often insufflated into a body cavity to inflate the cavity for more workroom, e.g. during laparoscopic surgery. The most common gas used in this manner is carbon dioxide, because it is non-flammable, colorless, and dissolves readily in blood.
Diagnostics
Gases can be insufflated into parts of the body to enhance radiological imaging or to gain access to areas for visual inspection (e.g. during colonoscopy).
Respiratory assistance
Oxygen can be insufflated into the nose by nasal cannulae to assist in respiration.
Mechanical insufflation-exsufflation simulates a cough and assists airway mucus clearance. It is used with patients with neuromuscular disease and muscle weakness due to central nervous system injury.
Glossopharyngeal insufflation is a breathing technique that consists of gulping boluses of air into the lungs. It is also used by breath-hold divers to increase their lung volumes.
Positive airway pressure is a mode of mechanical or artificial ventilation based on insufflation.
Pump inhalers for asthmatics deliver aerosolized drugs into the lungs via the mouth. However, the insufflation by the pump is not adequate for delivery to the lungs, necessitating an active inhalation by the patient.
Anesthesia and critical care
Insufflated gases and vapors are used to ventilate and oxygenate patients (oxygen, air, helium), and to induce, assist in or maintain general anaesthesia (nitrous oxide, xenon, volatile anesthetic agents).
Positive airway pressure is a mode of mechanical or artificial ventilation based on insufflation.
Nasal drug administration
Nasal insufflation is the most common method of nasal administration. Other methods are nasal inhalation and nasal instillation. Drugs administered in this way can have a local e |
https://en.wikipedia.org/wiki/Cercopithecine%20gammaherpesvirus%2014 | Cercopithecine gammaherpesvirus 14 (CeHV-14) is a species of virus in the genus Lymphocryptovirus, subfamily Gammaherpesvirinae, family Herpesviridae, and order Herpesvirales. |
https://en.wikipedia.org/wiki/Superior%20cardiac%20nerve | The superior cardiac nerve arises by two or more branches from the superior cervical ganglion, and occasionally receives a filament from the trunk between the first and second cervical ganglia. It runs down the neck behind the common carotid artery, and in front of the Longus colli muscle; and crosses in front of the inferior thyroid artery, and recurrent nerve. The course of the nerves on the two sides then differs.
Right nerve
The right nerve, at the root of the neck, passes either in front of or behind the subclavian artery, and along the brachiocephalic trunk to the back of the arch of the aorta, where it joins the deep part of the cardiac plexus.
It is connected with other branches of the sympathetic; about the middle of the neck it receives filaments from the external laryngeal nerve; lower down, one or two twigs from the vagus; and as it enters the thorax it is joined by a filament from the recurrent laryngeal nerve.
Filaments from the nerve communicate with the thyroid branches from the middle cervical ganglion.
Left nerve
The left nerve, in the thorax, runs in front of the left common carotid artery and across the left side of the aortic arch, to the superficial part of the cardiac plexus. |
https://en.wikipedia.org/wiki/ISO/IEC%2010967 | ISO/IEC 10967, Language independent arithmetic (LIA), is a series of
standards on computer arithmetic. It is compatible with ISO/IEC/IEEE 60559:2011,
more known as IEEE 754-2008, and much of the
specifications are for IEEE 754 special values
(though such values are not required by LIA itself, unless the parameter iec559 is true).
It was developed by the working group ISO/IEC JTC1/SC22/WG11, which was disbanded in 2011.
LIA consists of three parts:
Part 1: Integer and floating point arithmetic, second edition published 2012.
Part 2: Elementary numerical functions, first edition published 2001.
Part 3: Complex integer and floating point arithmetic and complex elementary numerical functions, first edition published 2006.
Parts
Part 1
Part 1 deals with the basic integer and floating point datatypes (for multiple radices, including 2 and 10),
but unlike IEEE 754-2008 not the representation of the values. Part 1 also
deals with basic arithmetic, including comparisons, on values of such
datatypes. The parameter iec559 is expected to be
true for most implementations of LIA-1.
Part 1 was revised, to the second edition, to become more in line with the specifications
in parts 2 and 3.
Part 2
Part 2 deals with some additional "basic" operations on integer and floating point
datatype values, but focuses primarily on specifying requirements on numerical
versions of elementary functions. Much of the specifications in LIA-2 are inspired
by the specifications in Ada for elementary functions.
Part 3
Part 3 generalizes parts 1 and 2 to deal with imaginary and complex
datatypes and arithmetic and elementary functions on such values.
Much of the specifications in LIA-3 are inspired by the specifications
for imaginary and complex datatypes and operations in
C, Ada and
Common Lisp.
Bindings
Each of the parts provide suggested bindings for a number of
programming languages. These are not part of the LIA standards,
just suggestions, and are not complete. Authors of a programming
l |
https://en.wikipedia.org/wiki/Vis%20viva | Vis viva (from the Latin for "living force") is a historical term used to describe a quantity similar to kinetic energy in an early formulation of the principle of conservation of energy.
Overview
Proposed by Gottfried Leibniz over the period 1676–1689, the theory was controversial as it seemed to oppose the theory of conservation of quantity of motion advocated by René Descartes. Descartes' quantity of motion was different from momentum, but Newton defined the quantity of motion as the conjunction of the quantity of matter and velocity in Definition II of his Principia. In Definition III, he defined the force that resists a change in motion as the vis inertia of Descartes. His Third Law of Motion is also equivalent to the principle of conservation of momentum. Leibniz accepted the principle of conservation of momentum, but rejected the Cartesian version of it. The difference between these ideas was whether the quantity of motion was simply related to a body's resistance to a change in velocity (vis inertia) or whether a body's amount of force due to its motion (vis viva) was related to the square of its velocity.
The theory was eventually absorbed into the modern theory of energy, though the term still survives in the context of celestial mechanics through the vis viva equation. The English equivalent "living force" was also used, for example by George William Hill.
The term is due to German Gottfried Wilhelm Leibniz, who was the first to attempt a mathematical formulation from 1676 to 1689. Leibniz noticed that in many mechanical systems (of several masses, mi each with velocity vi) the quantity
was conserved. He called this quantity the vis viva or "living force" of the system. The principle represented an accurate statement of the conservation of kinetic energy in elastic collisions that was independent of the conservation of momentum.
However, many physicists at the time were unaware of this fact and, instead, were influenced by the prestige of Sir Isaac N |
https://en.wikipedia.org/wiki/Mobilome | The mobilome is the entire set of mobile genetic elements in a genome. Mobilomes are found in eukaryotes, prokaryotes, and viruses. The compositions of mobilomes differ among lineages of life, with transposable elements being the major mobile elements in eukaryotes, and plasmids and prophages being the major types in prokaryotes. Virophages contribute to the viral mobilome.
Mobilome in eukaryotes
Transposable elements are elements that can move about or propagate within the genome, and are the major constituents of the eukaryotic mobilome. Transposable elements can be regarded as genetic parasites because they exploit the host cell's transcription and translation mechanisms to extract and insert themselves in different parts of the genome, regardless of the phenotypic effect on the host.
Eukaryotic transposable elements were first discovered in maize (Zea mays) in which kernels showed a dotted color pattern. Barbara McClintock described the maize Ac/Ds system in which the Ac locus promotes the excision of the Ds locus from the genome, and excised Ds elements can mutate genes responsible for pigment production by inserting into their coding regions.
Other examples of transposable elements include: yeast (Saccharomyces cerevisiae) Ty elements, a retrotransposon which encodes a reverse transcriptase to convert its mRNA transcript into DNA which can then insert into other parts of the genome; and fruit fly (Drosophila melanogaster) P-elements, which randomly inserts into the genome to cause mutations in germ line cells, but not in somatic cells.
Mobilome in prokaryotes
Plasmids were discovered in the 1940s as genetic materials outside of bacterial chromosomes. Prophages are genomes of bacteriophages (a type of virus) that are inserted into bacterial chromosomes; prophages can then be spread to other bacteria through the lytic cycle and lysogenic cycle of viral replication.
While transposable elements are also found in prokaryotic genomes, the most common mobile |
https://en.wikipedia.org/wiki/Time/memory/data%20tradeoff%20attack | A time/memory/data tradeoff attack is a type of cryptographic attack where an attacker tries to achieve a situation similar to the space–time tradeoff but with the additional parameter of data, representing the amount of data available to the attacker. An attacker balances or reduces one or two of those parameters in favor of the other one or two. This type of attack is very difficult, so most of the ciphers and encryption schemes in use were not designed to resist it.
History
Tradeoff attacks on symmetric cryptosystems date back to 1980, when Martin Hellman suggested a time/memory tradeoff method to break block ciphers with possible keys in time and memory related by the tradeoff curve where . Later, in 1995, Babbage and Golic devised a different tradeoff attack for stream ciphers with a new bound such that for where is the output data available to the cryptanalyst at real time.
Attack mechanics
This attack is a special version of the general cryptanalytic time/memory tradeoff attack, which has two main phases:
Preprocessing: During this phase, the attacker explores the structure of the cryptosystem and is allowed to record their findings in large tables. This can take a long time.
Realtime: In this phase, the cryptanalyst is granted real data obtained from a specific unknown key. They then try to use this data with the precomputed table from the preprocessing phase to find the particular key in as little time as possible.
Any time/memory/data tradeoff attack has the following parameters:
search space size
time required for the preprocessing phase
time required for the realtime phase
amount of memory available to the attacker
amount of realtime data available to the attacker
Hellman's attack on block ciphers
For block ciphers, let be the total number of possible keys and also assume the number of possible plaintexts and ciphertexts to be . Also let the given data be a single ciphertext block of a specific plaintext counterpart. If we co |
https://en.wikipedia.org/wiki/Acta%20Biotheoretica | Acta Biotheoretica: Mathematical and philosophical foundations of biological and biomedical science is a quarterly peer-reviewed scientific journal published by Springer Science+Business Media. It is the official journal of the Jan van der Hoeven Society for Theoretical Biology. The editor-in-chief is F.J.A. Jacobs (Leiden University).
Aims and scope
The journal's focus is theoretical biology which includes mathematical representation, treatment, and modeling for simulations and quantitative descriptions. The journal's focus also includes the philosophy of biology which emphasizes looking at the methods developed to form biological theory. Topical coverage also includes biomathematics, computational biology, genetics, ecology, and morphology.
Abstracting and indexing
This journal is abstracted and indexed in:
According to the Journal Citation Reports, the journal has a 2021 impact factor of 1.185. According to the SCImago Journal Rank (SJR), the journal h-index is 35. |
https://en.wikipedia.org/wiki/Burberry | Burberry Group plc is a British luxury fashion house established in 1856 by Thomas Burberry and headquartered in London, England. It currently designs and distributes ready to wear, including trench coats (for which it is most famous), leather accessories, and footwear.
History
Early years, 19th century
Burberry was founded in 1856 when 21-year-old Thomas Burberry, a former draper's apprentice, opened his own store in Basingstoke, Hampshire, England. By 1870, the business had established itself by focusing on the development of outdoors attire. In 1879, Burberry introduced gabardine to his brand, a hardwearing, water-resistant yet breathable fabric, in which the yarn is waterproofed before weaving. In 1891, Burberry opened a shop in the Haymarket, London.
20th century
In 1901, the Burberry Equestrian Knight logo was developed containing the Latin word "Prorsum", meaning "forwards", and it was registered as a trademark in 1909. In 1911, the company became the outfitters for Roald Amundsen, the first man to reach the South Pole, and Ernest Shackleton, who led a 1914 expedition to cross Antarctica. A Burberry gabardine jacket was worn by George Mallory on his attempt on Mount Everest in 1924.
Adapted to meet the needs of military personnel, the "trench coat" was born during the First World War; it was worn by British officers in the trenches. After the war, it became popular with civilians. The Burberry check has been in use since at least the 1920s, primarily as a lining in its trench coats. The celebrity motorcycling sisters Betty and Nancy Debenham wore their trench coats for travelling and racing in the 1920s and recommeded the garment in their 1928 book Motor-Cycling for Women. Burberry also specially designed aviation garments. They outfitted Mrs Victor Bruce for her 1930 round the world flight and her one woman flight to Japan. She wore a reversible coat with waterproof gabardine outside for flying and with a tweed inner side which could be turned outside t |
https://en.wikipedia.org/wiki/Halley%27s%20method | In numerical analysis, Halley's method is a root-finding algorithm used for functions of one real variable with a continuous second derivative. It is named after its inventor Edmond Halley.
The algorithm is second in the class of Householder's methods, after Newton's method. Like the latter, it iteratively produces a sequence of approximations to the root; their rate of convergence to the root is cubic. Multidimensional versions of this method exist.
Halley's method exactly finds the roots of a linear-over-linear Padé approximation to the function, in contrast to Newton's method or the Secant method which approximate the function linearly, or Muller's method which approximates the function quadratically.
Method
Edmond Halley was an English mathematician who introduced the method now called by his name. Halley's method is a numerical algorithm for solving the nonlinear equation f(x) = 0. In this case, the function f has to be a function of one real variable. The method consists of a sequence of iterations:
beginning with an initial guess x0.
If f is a three times continuously differentiable function and a is a zero of f but not of its derivative, then, in a neighborhood of a, the iterates xn satisfy:
This means that the iterates converge to the zero if the initial guess is sufficiently close, and that the convergence is cubic.
The following alternative formulation shows the similarity between Halley's method and Newton's method. The expression is computed only once, and it is particularly useful when can be simplified:
When the second derivative is very close to zero, the Halley's method iteration is almost the same as the Newton's method iteration.
Derivation
Consider the function
Any root of f which is not a root of its derivative is a root of g; and any root r of g must be a root of f provided the derivative of f at r is not infinite. Applying Newton's method to g gives
with
and the result follows. Notice that if f′ (c) = 0, then one cannot apply thi |
https://en.wikipedia.org/wiki/Virtual%20file%20server | In computing, a virtual file server is a system consisting of one or more virtualized devices that store computer files such as documents, sound files, photographs, movies, images, or databases. The server can be accessed by workstations or application servers through the Virtual Fileserver Network (VFN).
The term "server" highlights the role of the virtual machine in the client-server scheme, where the clients are the applications accessing the storage. The file server usually does not run application programs on behalf of the clients. It enables storage and retrieval of data, where the computation is provided by the client. With a storage area network (SAN), the server(s) act purely as virtual storage devices, with a client maintaining the file system. With network-attached storage (NAS), the server(s) manage the file system. Both SAN and NAS servers may be virtualized, so the users do not have to know which physical devices are hosting the files.
A virtual file server typically combines the security of virtual private networks (VPN) with file synchronization, distribution and sharing services of network file servers.
Various companies offer software for use by an organization in managing virtual file servers. The operating system may be stripped-down, concerned only with file management functions such as synchronizing redundant copies of the file, failure recovery, handling concurrent updates from different clients and enforcing client access rights. Some companies offer virtual file servers as a service to organizations that prefer to outsource server operations, with the servers residing in the "cloud".
See also
Storage virtualization
Storage area network
Network-attached storage
Virtual private network
Platform as a service |
https://en.wikipedia.org/wiki/No%20free%20lunch%20theorem | In mathematical folklore, the "no free lunch" (NFL) theorem (sometimes pluralized) of David Wolpert and William Macready, alludes to the saying "no such thing as a free lunch", that is, there are no easy shortcuts to success. It appeared in the 1997 "No Free Lunch Theorems for Optimization". Wolpert had previously derived no free lunch theorems for machine learning (statistical inference).
In 2005, Wolpert and Macready themselves indicated that the first theorem in their paper "state[s] that any two optimization algorithms are equivalent when their performance is averaged across all possible problems".
The "no free lunch" (NFL) theorem is an easily stated and easily understood consequence of theorems Wolpert and Macready actually prove. It is weaker than the proven theorems, and thus does not encapsulate them. Various investigators have extended the work of Wolpert and Macready substantively. In terms of how the NFL theorem is used in the context of the research area, the no free lunch in search and optimization is a field that is dedicated for purposes of mathematically analyzing data for statistical identity, particularly search and optimization.
While some scholars argue that NFL conveys important insight, others argue that NFL is of little relevance to machine learning research.
Example
Posit a toy universe that exists for exactly two days and on each day contains exactly one object, a square or a triangle. The universe has exactly four possible histories:
(square, triangle): the universe contains a square on day 1, and a triangle on day 2
(square, square)
(triangle, triangle)
(triangle, square)
Any prediction strategy that succeeds for history #2, by predicting a square on day 2 if there is a square on day 1, will fail on history #1, and vice versa. If all histories are equally likely, then any prediction strategy will score the same, with the same accuracy rate of 0.5.
Origin
Wolpert and Macready give two NFL theorems that are closely related to the |
https://en.wikipedia.org/wiki/LILRA2 | Leukocyte immunoglobulin-like receptor subfamily A member 2 (LILRA2, CD85H, ILT1) is a protein that in humans is encoded by the LILRA2 gene.
Leukocyte Ig-like receptors (LIRs) are a family of immunoreceptors expressed predominantly on monocytes and B cells and at lower levels on dendritic cells and natural killer (NK) cells. All LIRs in subfamily B have an inhibitory function (see, e.g., LILRB1, MIM 604811). LIRs in subfamily A, with short cytoplasmic domains lacking an immunoreceptor tyrosine-based inhibitory motif (ITIM) and with transmembrane regions containing a charged arginine residue, may initiate stimulatory cascades. One member of subfamily A (LILRA3; MIM 604818) lacks a transmembrane region and is presumed to be a soluble receptor.[supplied by OMIM]
Function
LILRA2 senses microbially cleaved immunoglobulin to activate human myeloid cells.
See also
Cluster of differentiation |
https://en.wikipedia.org/wiki/GPANG | GPANG (Korean: 지팡) was a 3D mobile game service introduced in 2004 by the Korean provider KTF. This service allowed subscribers to access a downloadable game portal and play advanced 3D mobile games, including MMOs. KTF's GPANG competed with SK Telecom's own 3D mobile game service called GXG. On June 1 2009, GPANG ceased to exist.
Compatible devices
LG KV3600 (2005)
Samsung SPH-G1000 (2005)
Samsung SPH-B3200 (2006)
Games
72 released games are known to exist, with 1 unreleased game.
See also
GXG
N-Gage |
https://en.wikipedia.org/wiki/Blastocyst | The blastocyst is a structure formed in the early embryonic development of mammals. It possesses an inner cell mass (ICM) also known as the embryoblast which subsequently forms the embryo, and an outer layer of trophoblast cells called the trophectoderm. This layer surrounds the inner cell mass and a fluid-filled cavity known as the blastocoel. In the late blastocyst the trophectoderm is known as the trophoblast. The trophoblast gives rise to the chorion and amnion, the two fetal membranes that surround the embryo. The placenta derives from the embryonic chorion (the portion of the chorion that develops villi) and the underlying uterine tissue of the mother.
The name "blastocyst" arises from the Greek ("a sprout") and ("bladder, capsule").
In non-mammalian animals this is a structure consisting of an undifferentiated ball of cells and is called a blastula.
In humans, blastocyst formation begins about five days after fertilization when a fluid-filled cavity opens up in the morula, the early embryonic stage of a ball of 16 cells.
The blastocyst has a diameter of about 0.1–0.2 mm and comprises 200–300 cells (32 mitotic divisions ) following rapid cleavage (cell division). About seven days after fertilization, the blastocyst undergoes implantation, embedding into the endometrium of the uterine wall where it will undergo further developmental processes, including gastrulation. Embedding of the blastocyst into the endometrium requires that it hatches from the zona pellucida, the egg coat that prevents adherence to the fallopian tube as the pre-embryo makes its way to the uterus.
The use of blastocysts in in vitro fertilization (IVF) involves culturing a fertilized egg for five days before transferring it into the uterus. It can be a more viable method of fertility treatment than traditional IVF. The inner cell mass of blastocysts is the source of embryonic stem cells, which are broadly applicable in stem cell therapies including cell repair, replacement and rege |
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