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https://en.wikipedia.org/wiki/Sidney%20Siegel | Sidney Siegel (4 January 1916 in New York City – 29 November 1961) was an American psychologist who became especially well known for his work in popularizing non-parametric statistics for use in the behavioral sciences. He was a co-developer of the statistical test known as the Siegel–Tukey test.
In 1951 Siegel completed a B.A. in vocational arts at San Jose State College (now San Jose State University), then in 1953 a Ph.D. in Psychology at Stanford University. Except for a year spent at the Center for Advanced Study in the Behavioral Sciences at Stanford, he thereafter taught at Pennsylvania State University, until his death in November 1961 of a coronary thrombosis.
His parents, Jacob and Rebecca Siegel, were Jewish immigrants from Romania.
See also
Siegel–Tukey test.
Notes |
https://en.wikipedia.org/wiki/Trope%20%28mathematics%29 | In geometry, trope is an archaic term for a singular (meaning special) tangent space of a variety, often a quartic surface. The term may have been introduced by , who defined it as "the reciprocal term to node". It is not easy to give a precise definition, because the term is used mainly in older books and papers on algebraic geometry, whose definitions are vague and different, and use archaic terminology. The term trope is used in the theory of quartic surfaces in projective space, where it is sometimes defined as a tangent space meeting the quartic surface in a conic; for example Kummer's surface has 16 tropes.
, describes a trope as a tangent plane where the envelope of nearby tangent planes forms a conic, rather than a plane pencil which we would expect for a generic point. The tangent plane would be tangent to the quartic along the conic, implying that the Gauss map would have a singular point.
See also
Glossary of classical algebraic geometry |
https://en.wikipedia.org/wiki/China%20Dark%20Matter%20Experiment | The China Dark Matter Experiment (CDEX) is a search for dark matter WIMP particles at the China Jinping Underground Laboratory. CDEX was the first experiment to be hosted at CJPL, beginning construction of its shield in June 2010, the same month that laboratory construction was completed, and before CJPL's official opening on 12 December.
CDEX has p-type point-contact germanium detector surrounded by NaI(Tl) crystals, similar to the CoGeNT experiment. The CDEX-0 prototype was used to develop the current CDEX-1 detector, which has a detector mass of roughly 1 kg. Future plans include scaling to CDEX-10 and CDEX-1T.
CDEX-1 had first low mass results in 2013 and published limits on WIMP masses 6–20 GeV in 2014. |
https://en.wikipedia.org/wiki/Haitian%20border%20threadsnake | The Haitian border threadsnake (Mitophis leptepileptus) is a possibly extinct species of snake in the family Leptotyphlopidae endemic to Haiti.
Description
Last seen in 1984, the species was thought to be already rare, but intensive surveys in the area have not recorded it. If it is extinct, causes are certainly due to deforestation of its habitat and agricultural activities, which have intensified since its last collection. |
https://en.wikipedia.org/wiki/Vexillary%20permutation | In mathematics, a vexillary permutation is a permutation μ of the positive integers containing no subpermutation isomorphic to the permutation (2143); in other words, there do not exist four numbers i < j < k < l with μ(j) < μ(i) < μ(l) < μ(k). They were introduced by . The word "vexillary" means flag-like, and comes from the fact that vexillary permutations are related to flags of modules.
showed that vexillary involutions are enumerated by Motzkin numbers.
See also
Riffle shuffle permutation, a subclass of the vexillary permutations |
https://en.wikipedia.org/wiki/Regular%20modal%20logic | In modal logic, a regular modal logic is a modal logic containing (as axiom or theorem) the duality of the modal operators:
and closed under the rule
Every normal modal logic is regular, and every regular modal logic is classical. |
https://en.wikipedia.org/wiki/Supervisor%20Call%20instruction | This article covers the specific instruction on the IBM System/360 and successor mainframe computers, and compatible machines. For the general concept of an instruction for issuing calls to an operating system, see System call.
A Supervisor Call instruction (SVC) is a hardware instruction used by the System/360 family of IBM mainframe computers up to contemporary zSeries, the Amdahl 470V/5, 470V/6, 470V/7, 470V/8, 580, 5880, 5990M, and 5990A, and others; Univac 90/60, 90/70 and 90/80, and possibly others; the Fujitsu M180 (UP) and M200 (MP), and others; and is also used in the Hercules open source mainframe emulation software. It causes an interrupt to request a service from the operating system. The system routine providing the service is called an SVC routine. SVC is a system call.
Rationale
IBM mainframes in the System/360 and successor families operate in one of two states: problem state or supervisor state and in one of sixteen storage access keys (0 to 15). In problem state, a large set of general purpose non-privileged instructions are available to a user program. In supervisor state, system programs are additionally able to use a small set of privileged instructions which are generally intended for supervisory functions. These functions may affect other users, other processors, or the entire computer system. In storage key 0 a program is able to access all addressable storage, otherwise it is limited to storage areas with a matching key.
A program is only allowed to access specific supervisory functions after thorough authorization checking by the operating system: DEBCHK (SVC 117), TESTAUTH (SVC 119), and possibly additional tests. Programs which fail any of these tests are ABENDed, that is abnormally terminated and immediately cease processing. Some of these tests were not available in OS/360, but were added in OS/VS1, SVS or MVS/370, but all were available in MVS/370 or subsequent releases, and are still available to this day.
In OS/VS1, OS/VS2 (SVS) |
https://en.wikipedia.org/wiki/Low-voltage%20detect | A low-voltage detect (LVD) is a microcontroller or microprocessor peripheral that generates a reset signal when the Vcc supply voltage falls below Vref. Sometimes is combined with power-on reset (POR) and then it is called POR-LVD.
See also
Power-on reset
Embedded systems |
https://en.wikipedia.org/wiki/Inflorescence | An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes.
One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern.
The stem holding the whole inflorescence is called a peduncle. The major axis (incorrectly referred to as the main stem) above the peduncle bearing the flowers or secondary branches is called the rachis. The stalk of each flower in the inflorescence is called a pedicel. A flower that is not part of an inflorescence is called a solitary flower and its stalk is also referred to as a peduncle. Any flower in an inflorescence may be referred to as a floret, especially when the individual flowers are particularly small and borne in a tight cluster, such as in a pseudanthium.
The fruiting stage of an inflorescence is known as an infructescence.
Inflorescences may be simple (single) or complex (panicle). The rachis may be one of several types, including single, composite, umbel, spike or raceme.
In some species the flowers develop directly from the main stem or woody trunk, rather than from the plant's main shoot. This is called cauliflory and is found across a number of plant families. An extreme version of this is flagelliflory where long, whip-like branches grow from the main trunk to the ground and even below it. Inflorescences form directly on these branches.
General characteristics
Inflorescences are described by many different characteristics including how the flowers are arranged on the peduncle, the blooming order of the flowers, and how different clust |
https://en.wikipedia.org/wiki/Metabolic%20network | A metabolic network is the complete set of metabolic and physical processes that determine the physiological and biochemical properties of a cell. As such, these networks comprise the chemical reactions of metabolism, the metabolic pathways, as well as the regulatory interactions that guide these reactions.
With the sequencing of complete genomes, it is now possible to reconstruct the network of biochemical reactions in many organisms, from bacteria to human. Several of these networks are available online:
Kyoto Encyclopedia of Genes and Genomes (KEGG), EcoCyc, BioCyc and metaTIGER.
Metabolic networks are powerful tools for studying and modelling metabolism.
Uses
Metabolic networks can be used to detect comorbidity patterns in diseased patients. Certain diseases, such as obesity and diabetes, can be present in the same individual concurrently, sometimes one disease being a significant risk factor for the other disease. The disease phenotypes themselves are normally the consequence of the cell's inability to breakdown or produce an essential substrate. However, an enzyme defect at one reaction may affect the fluxes of other subsequent reactions. These cascading effects couple the metabolic diseases associated with subsequent reactions resulting in comorbidity effects. Thus, metabolic disease networks can be used to determine if two disorders are connected due to their correlated reactions.
See also
Metabolic network modelling
Metabolic pathway |
https://en.wikipedia.org/wiki/Redshift%20conjecture | In mathematics, more specifically in chromatic homotopy theory, the redshift conjecture states, roughly, that algebraic K-theory has chromatic level one higher than that of a complex-oriented ring spectrum R.
It was formulated by John Rognes in a lecture at Schloss Ringberg, Germany, in January 1999, and made more precise by him in a lecture at Mathematische Forschungsinstitut Oberwolfach, Germany, in September 2000. In July 2022, Burklund, Schlank and Yuan announced a solution of a version of the redshift conjecture for arbitrary -ring spectra, after Hahn and Wilson did so earlier in the case of the truncated Brown-Peterson spectra BP<n>. |
https://en.wikipedia.org/wiki/Bolbitis%20appendiculata | Bolbitis appendiculata is a lithophyte in the family Dryopteridaceae, seen in evergreen forests. It is found in India, Sri Lanka, Bangladesh, Borneo, Myanmar, Cambodia, China, Hong Kong, Japan, Java, Malaysia, Philippines, Sumatra, Taiwan, Thailand and Vietnam. Fronds are dimorphic, scaly beneath and hairy above. Sterile lamina dark green and simply pinnate, stalked, oblong, serrate with larger pinnae in the middle, reduced towards both ends. Fertile lamina narrower, elliptic, obtuse and base unequal. Dark brown to black sporangia covers almost the entirety of the underside of the leaf surface (acrostichoid). |
https://en.wikipedia.org/wiki/Phenol-Explorer | Phenol-Explorer is a comprehensive database on natural phenols and polyphenols including food composition, food processing, and polyphenol metabolites in human and experimental animals.
See also
Food composition data |
https://en.wikipedia.org/wiki/Mulliken%20population%20analysis | Mulliken charges arise from the Mulliken population analysis and provide a means of estimating partial atomic charges from calculations carried out by the methods of computational chemistry, particularly those based on the linear combination of atomic orbitals molecular orbital method, and are routinely used as variables in linear regression (QSAR) procedures. The method was developed by Robert S. Mulliken, after whom the method is named. If the coefficients of the basis functions in the molecular orbital are Cμi for the μ'th basis function in the i'th molecular orbital, the density matrix terms are:
for a closed shell system where each molecular orbital is doubly occupied. The population matrix then has terms
is the overlap matrix of the basis functions. The sum of all terms of summed over is the gross orbital product for orbital - . The sum of the gross orbital products is N - the total number of electrons. The Mulliken population assigns an electronic charge to a given atom A, known as the gross atom population: as the sum of over all orbitals belonging to atom A. The charge, , is then defined as the difference between the number of electrons on the isolated free atom, which is the atomic number , and the gross atom population:
Mathematical problems
Off-diagonal terms
One problem with this approach is the equal division of the off-diagonal terms between the two basis functions. This leads to charge separations in molecules that are exaggerated. In a modified Mulliken population analysis, this problem can be reduced by dividing the overlap populations between the corresponding orbital populations and in the ratio between the latter. This choice, although still arbitrary, relates the partitioning in some way to the electronegativity difference between the corresponding atoms.
Ill definition
Another problem is the Mulliken charges are explicitly sensitive to the basis set choice. In principle, a complete basis set for a molecule can be spanned |
https://en.wikipedia.org/wiki/Symmetric%20closure | In mathematics, the symmetric closure of a binary relation on a set is the smallest symmetric relation on that contains
For example, if is a set of airports and means "there is a direct flight from airport to airport ", then the symmetric closure of is the relation "there is a direct flight either from to or from to ". Or, if is the set of humans and is the relation 'parent of', then the symmetric closure of is the relation " is a parent or a child of ".
Definition
The symmetric closure of a relation on a set is given by
In other words, the symmetric closure of is the union of with its converse relation,
See also |
https://en.wikipedia.org/wiki/Holland%27s%20schema%20theorem | Holland's schema theorem, also called the fundamental theorem of genetic algorithms, is an inequality that results from coarse-graining an equation for evolutionary dynamics. The Schema Theorem says that short, low-order schemata with above-average fitness increase exponentially in frequency in successive generations. The theorem was proposed by John Holland in the 1970s. It was initially widely taken to be the foundation for explanations of the power of genetic algorithms. However, this interpretation of its implications has been criticized in several publications reviewed in, where the Schema Theorem is shown to be a special case of the Price equation with the schema indicator function as the macroscopic measurement.
A schema is a template that identifies a subset of strings with similarities at certain string positions. Schemata are a special case of cylinder sets, and hence form a topological space.
Description
Consider binary strings of length 6. The schema 1*10*1 describes the set of all strings of length 6 with 1's at positions 1, 3 and 6 and a 0 at position 4. The * is a wildcard symbol, which means that positions 2 and 5 can have a value of either 1 or 0. The order of a schema is defined as the number of fixed positions in the template, while the defining length is the distance between the first and last specific positions. The order of 1*10*1 is 4 and its defining length is 5. The fitness of a schema is the average fitness of all strings matching the schema. The fitness of a string is a measure of the value of the encoded problem solution, as computed by a problem-specific evaluation function. Using the established methods and genetic operators of genetic algorithms, the schema theorem states that short, low-order schemata with above-average fitness increase exponentially in successive generations. Expressed as an equation:
Here is the number of strings belonging to schema at generation , is the observed average fitness of schema and is the |
https://en.wikipedia.org/wiki/Allow%20natural%20death | Allow Natural Death (AND) is a medical term defining the use of life-extending measures such as cardiopulmonary resuscitation (CPR). These orders emphasize patient comfort and pain management instead of life extension. Currently, American medical communities utilize "do not resuscitate," (DNR) orders to define patients' medical wishes. Those who propose to replace DNR with AND posit that DNR orders are ambiguous and require complex understanding between several parties, while AND orders are clearer. Proponents of replacing DNR with AND believe that AND terminology is more ethically conscientious DNR terminology. Research has been conducted regarding participant preference for AND vs. DNR terminology. The ease with which the terminology change can be practically incorporated depends on many factors such as costs and staff reeducation.
DNR vs. AND
DNR orders range in the extent of life-saving measures to be avoided, from solely prohibiting the use of resuscitation to prohibiting any action seen as life extending. Because there are many parties involved in a patient's end of life care - significant others, family, personal doctors, specialists and nurses - DNR orders are not always completely clear, leaving open possible violation of the patient's wishes. DNR terminology was replaced in 2005 by the American Heart Association with Do Not Attempt Resuscitation (DNAR) in an effort to make clearer the meaning of the order. However, DNR remains the popularly understood and used term in the medical and layperson settings. AND is yet another phrase for similar orders, and implementing it involves a term change.
Those who propose to replace DNR orders with AND orders posit that AND is less ambiguous, clearly instructing medical personnel to not use any artificial, life extending measures. This would be especially helpful in regards to emergency care, when medical personnel who are unfamiliar with the patient must decide what medical practices should be used. Pros are that |
https://en.wikipedia.org/wiki/Apple%20Push%20Notification%20service | Apple Push Notification service (commonly referred to as Apple Notification Service or APNs) is a platform notification service created by Apple Inc. that enables third party application developers to send notification data to applications installed on Apple devices. The notification information sent can include badges, sounds, newsstand updates, or custom text alerts. It was first launched with iOS 3 on June 17, 2009. APNs support for local applications was later added to the Mac OS X API beginning with the release of Mac OS X 10.7 ("Lion"). Support for website notifications was later added with the release of Mac OS X 10.9 ("Mavericks").
History
Apple announced the service on June 9, 2008 with an original stated release for that September; however, as stated by Scott Forstall at the iOS 3.0 preview event on March 17, 2009, the rollout was delayed after a decision to restructure the APNs for scalability purposes due to the allegedly "overwhelming" response to the announcement of the APNs. At both events, Forstall stated that push notifications better conserve battery than background processes (which are used in pull technology) for receiving notifications.
APNs was first launched together with iOS 3.0 on June 17, 2009. The release of iOS 5.0 included a Notification Center, adding support for receiving and reading local notifications in a single place.
APNs was also added as an API to Mac OS X 10.7 ("Lion") so that developers could begin updating their third-party applications and start utilizing the service. Support was later improved in OS X 10.8 ("Mountain Lion") with the introduction of a Notification Center. As with iOS 5.0, the improvement allowed users to manage and read their received notifications in a single location. The release of OS X 10.9 ("Mavericks") included Safari 7.0, which added support for accepting and receiving APNs notifications from websites that the user granted permission to.
Technical details
In 2014, the maximum size allowed for a n |
https://en.wikipedia.org/wiki/Separating%20set | In mathematics, a set of functions with domain is called a and is said to (or just ) if for any two distinct elements and of there exists a function such that
Separating sets can be used to formulate a version of the Stone–Weierstrass theorem for real-valued functions on a compact Hausdorff space with the topology of uniform convergence. It states that any subalgebra of this space of functions is dense if and only if it separates points. This is the version of the theorem originally proved by Marshall H. Stone.
Examples
The singleton set consisting of the identity function on separates the points of
If is a T1 normal topological space, then Urysohn's lemma states that the set of continuous functions on with real (or complex) values separates points on
If is a locally convex Hausdorff topological vector space over or then the Hahn–Banach separation theorem implies that continuous linear functionals on separate points.
See also |
https://en.wikipedia.org/wiki/Halorhabdus%20utahensis | Halorhabdus utahensis is a halophilic archaeon isolated from the Great Salt Lake in Utah.
Cell structure and metabolism
Halorhabdus utahensis (salt-loving rod) is a motile, Gram-negative, extremely halophilic archaeon that forms red, circular colonies. It grows at the temperatures between 17 and 55 °C, with optimal growth occurring at 50 °C. It can also grow over a pH range of 5.5–8.5 with the optimal pH value between 6.7 and 7.1. Further, with its extremely high salinity optimum of 27% NaCl, Halorhabdus has one of the highest reported salinity optima of any living organism.
The cells of H. utahensis are extremely pleomorphic, exhibiting any shape from irregular coccoid or ellipsoid to triangular, club-shaped or rod-shaped forms. The rod-shaped and ellipsoid cells are 2-10 by 0.5-1 µm and 1-2 by 1 µm in size, respectively, and the spherical cells have a diameter of approximately 1 µm. The archaeon uses only a limited range of substrates, such as glucose, xylose, and fructose, for growth, and is unique in its inability to utilize yeast extract or peptone. Other substances that did not stimulate the organism's growth include organic acids, amino acids, alcohols, glycogen, and starch. |
https://en.wikipedia.org/wiki/Human%20behaviour%20genetics | Human behaviour genetics is an interdisciplinary subfield of behaviour genetics that studies the role of genetic and environmental influences on human behaviour. Classically, human behavioural geneticists have studied the inheritance of behavioural traits. The field was originally focused on determining the importance of genetic influences on human behaviour (for e.g., do genes regulate human behavioural attributes). It has evolved to address more complex questions such as: how important are genetic and/or environmental influences on various human behavioural traits; to what extent do the same genetic and/or environmental influences impact the overlap between human behavioural traits; how do genetic and/or environmental influences on behaviour change across development; and what environmental factors moderate the importance of genetic effects on human behaviour (gene-environment interaction). The field is interdisciplinary, and draws from genetics, psychology, and statistics. Most recently, the field has moved into the area of statistical genetics, with many behavioural geneticists also involved in efforts to identify the specific genes involved in human behaviour, and to understand how the effects associated with these genes changes across time, and in conjunction with the environment.
Traditionally, the human behavioural genetics were a psychology and phenotype based studies including intelligence, personality and grasping ability. During the years, the study developed beyond the classical traits of human behaviour and included more genetically associated traits like genetic disorders (such as fragile X syndrome, Alzheimer's disease and obesity). The traditional methods of behavioural-genetic analysis provide a quantitative evaluation of genetic and non-genetic influences on human behaviour. The family, twin and adoption studies marks the huge contribution for laying down the foundation for current molecular genetic studies to study human behaviour.
History
In 1 |
https://en.wikipedia.org/wiki/EMSO%20simulator | EMSO simulator is an equation-oriented process simulator with a graphical interface for modeling complex dynamic or steady-state processes. It is CAPE-OPEN compliant. EMSO stands for Environment for Modeling, Simulation, and Optimization. The ALSOC Project - a Portuguese acronym for Free Environment for Simulation, Optimization and Control of Processes -, which is based at the UFRGS, develops, maintains and distributes this object-oriented software. Pre-built models are available in the EMSO Modeling Library (EML). New models can be written in the EMSO modeling language or a user can embed models coded in C, C++ or Fortran into the simulation environment.
See also
AMPL
APMonitor
ASCEND
General Algebraic Modeling System
JModelica.org
MATLAB
Modelica
List of chemical process simulators |
https://en.wikipedia.org/wiki/Medial%20condyle%20of%20tibia | The medial condyle is the medial (or inner) portion of the upper extremity of tibia.
It is the site of insertion for the semimembranosus muscle.
See also
Lateral condyle of tibia
Medial collateral ligament
Additional images |
https://en.wikipedia.org/wiki/Helioseismology | Helioseismology, a term coined by Douglas Gough, is the study of the structure and dynamics of the Sun through its oscillations. These are principally caused by sound waves that are continuously driven and damped by convection near the Sun's surface. It is similar to geoseismology, or asteroseismology (also coined by Gough), which are respectively the studies of the Earth or stars through their oscillations. While the Sun's oscillations were first detected in the early 1960s, it was only in the mid-1970s that it was realized that the oscillations propagated throughout the Sun and could allow scientists to study the Sun's deep interior. The modern field is separated into global helioseismology, which studies the Sun's resonant modes directly, and local helioseismology, which studies the propagation of the component waves near the Sun's surface.
Helioseismology has contributed to a number of scientific breakthroughs. The most notable was to show the predicted neutrino flux from the Sun could not be caused by flaws in stellar models and must instead be a problem of particle physics. The so-called solar neutrino problem was ultimately resolved by neutrino oscillations. The experimental discovery of neutrino oscillations was recognized by the 2015 Nobel Prize for Physics. Helioseismology also allowed accurate measurements of the quadrupole (and higher-order) moments of the Sun's gravitational potential, which are consistent with General Relativity. The first helioseismic calculations of the Sun's internal rotation profile showed a rough separation into a rigidly-rotating core and differentially-rotating envelope. The boundary layer is now known as the tachocline and is thought to be a key component for the solar dynamo. Although it roughly coincides with the base of the solar convection zone — also inferred through helioseismology — it is conceptually distinct, being a boundary layer in which there is a meridional flow connected with the convection zone and dr |
https://en.wikipedia.org/wiki/Expected%20progeny%20difference | Expected progeny differences (EPD) are an evaluation of an animal’s genetic worth as a parent. They are based on animal models which combine all information known about an individual and its relatives to create a genetic profile of the animal’s merits. These profiles are then compared to other individuals of the same breed.
Types of EPDs
An example of a set of EPDs looks like the following chart. Each set of letters stands for a specific measurement with an accuracy reading and percent rank below it. Each EPD is compared to the breed average of a given year. The number given by the EPD is the amount above or below this given average.
Growth EPDs
Growth EPDs measure the amount of weight a given offspring will gain due to the parent's genetics.
Calving ease predicts the level of difficulty first time heifers will have during birth. These are determined by the percentage of unassisted births for that particular animal.
Birth weight measures how much above or below the breed's average an offspring will gain due to the parent. It does not necessarily predict the exact weight of all offspring, but instead gives a general prediction of how much extra or less weight an offspring will weigh compared to if it had been sired by another bull. High birth weight is the biggest cause of difficulty in calving, so having a bull with a low birth weight EPD is high beneficial.
Weaning and yearling weight measure the amount of weight an offspring has gained by the time it is weaned and at the one year mark. Typically the weaning weight is measured at the 205-day mark and the yearling weight is taken at the 365-day mark. Typically a larger number is favored for both of these traits.
Milk EPDs give an estimate for the maternal portion of the weaning weight that determined by milk production of the dam. It is measured in pounds of weaning weight of a bull's grandprogeny due to the milk production of the bull's daughters.
Reproductive EPDs
Scrotal circumference is an indicator of a |
https://en.wikipedia.org/wiki/Reactive%20oxygen%20species%20production%20in%20marine%20microalgae | All living cells produce reactive oxygen species (ROS) as a byproduct of metabolism. ROS are reduced oxygen intermediates that include the superoxide radical (O2−) and the hydroxyl radical (OH•), as well as the non-radical species hydrogen peroxide (H2O2). These ROS are important in the normal functioning of cells, playing a role in signal transduction and the expression of transcription factors. However, when present in excess, ROS can cause damage to proteins, lipids and DNA by reacting with these biomolecules to modify or destroy their intended function. As an example, the occurrence of ROS have been linked to the aging process in humans, as well as several other diseases including Alzheimer's, rheumatoid arthritis, Parkinson's, and some cancers. Their potential for damage also makes reactive oxygen species useful in direct protection from invading pathogens, as a defense response to physical injury, and as a mechanism for stopping the spread of bacteria and viruses by inducing programmed cell death.
Reactive oxygen species are present in low concentrations in seawater and are produced primarily through the photolysis of organic and inorganic matter. However, the biological production of ROS, generated through algal photosynthesis and subsequently 'leaked' to the environment, can contribute significantly to concentrations in the water column. Although there is very little information on the biological generation of ROS in marine surface waters, several species of marine phytoplankton have recently been shown to release significant amounts of ROS into the environment. This ROS has the potential to harm nearby organisms, and, in fact, has been implicated as the cause of massive fish, bacteria, and protist mortalities.
Chemical background
In sea water, ROS can be generated through abiotic as well as biotic processes, among which are the radiolysis and photolysis of water molecules and cellular respiration. According to a model proposed by Fan for the predi |
https://en.wikipedia.org/wiki/Sphenocorona | In geometry, the sphenocorona is one of the Johnson solids (). It is one of the elementary Johnson solids that do not arise from "cut and paste" manipulations of the Platonic and Archimedean solids.
Johnson uses the prefix spheno- to refer to a wedge-like complex formed by two adjacent lunes, a lune being a square with equilateral triangles attached on opposite sides. Likewise, the suffix -corona refers to a crownlike complex of 8 equilateral triangles. Joining both complexes together results in the sphenocorona.
Cartesian coordinates
Let k ≈ 0.85273 be the smallest positive root of the quartic polynomial
Then, Cartesian coordinates of a sphenocorona with edge length 2 are given by the union of the orbits of the points
under the action of the group generated by reflections about the xz-plane and the yz-plane.
One may then calculate the surface area of a sphenocorona of edge length a as
and its volume as
Variations
The sphenocorona is also the vertex figure of the isogonal n-gonal double antiprismoid where n is an odd number greater than one, including the grand antiprism with pairs of trapezoid rather than square faces.
See also
Augmented sphenocorona |
https://en.wikipedia.org/wiki/Nano-ITX | Nano-ITX is a computer motherboard form factor first proposed by VIA Technologies at CeBIT in March 2003, and implemented in late 2005. Nano-ITX boards measure , and are fully integrated, very low power consumption motherboards with many uses, but targeted at smart digital entertainment devices such as DVRs, set-top boxes, media centers, car PCs, and thin devices. Nano-ITX motherboards have slots for SO-DIMM.
There are four Nano-ITX motherboard product lines so far, VIA's EPIA N, EPIA NL, EPIA NX, and the VIA EPIA NR. These boards are available from a wide variety of manufacturers supporting numerous different CPU platforms.
Udoo has now released at least 1 nano-ITX board: the Udoo Bolt.
See also
Mini-ITX
Pico-ITX
Mobile-ITX
EPIA, mini-ITX and nano-ITX motherboards from VIA
Ultra-Mobile PC
Minimig, is an open source re-implementation of an Amiga 500 in Nano-ITX format |
https://en.wikipedia.org/wiki/Agene%20process | The agene process is a former process for bleaching flour with agene (nitrogen trichloride). The practice was discontinued in 1949 once it became known that agene treated flour caused severe and widespread neurological disorders in humans and dogs. |
https://en.wikipedia.org/wiki/Barak%20Kol%20%28physicist%29 | Barak Kol (born August 1968) is an Israeli theoretical physicist who studies fundamental laws, high-energy physics, and general relativity. He holds the Michael Polak chair in theoretical physics at the Racah Institute of Physics at the Hebrew University of Jerusalem.
Biography
Kol completed his BSc in physics and mathematics at Tel Aviv University in 1989, following which he did his military service in the IDF. Afterwards, he completed his PhD at Stanford University in 1998 under the guidance of Leonard Susskind, during which he coined the term "(p,q) webs." His most widely cited paper is on the subject and has over 500 citations.
Following the completion of his PhD, Kol was a postdoctoral fellow at Tel Aviv University (1998-2000) and at the Institute for Advanced Study (2000-2002). During the latter, he was hosted by Nathan Seiberg. Afterwards, he became a faculty member at the Racah Institute of Physics.
Kol's previous research topics include phase transitions in black strings, effective field theories in general relativity, black holes in string theory, and the three-body problem.
He was previously Head of the Physics Studies at the Racah Institute. |
https://en.wikipedia.org/wiki/Voxound | Voxound is a music web site that offers streaming through YouTube videos and plays local files through the use of a downloadable daemon. Voxound strives to generate a general classification of music (also known as a folksonomy of music) and encourages exploratory search.
History
The project was originally started by Jaime Bunzli as an attempt of solving his own needs for fixing and ordering his music collection. In 2007 he involved some of his colleagues at Pontificia Universidad Católica de Chile and started working in an initial Voxound prototype. In October 2008 the team got funding from family and friends and started from scratch. During the year 2009, Voxound developed a player for Windows, but its development was discontinued in early 2010. In October 2009, the Latin American Intel Challenge awarded them with $15.000 and tickets to participate in the Intel + UC Berkeley Technology Entrepreneurship Challenge.
As of 2010, the web application seems to be still under construction. As of 2013, the website is no longer accessible.
Features
The Voxound website features faceted search, which allows a user to refine search adding or excluding tags from the result set.
It also features a downloadable daemon which runs on Mac OS-X and Windows (there doesn’t seem to be a Linux version planned as of July 2010). The web application communicates with the daemon to find the metadata of the user's songs and plays local files through a flash plugin.
The site relies on the Facebook Platform as its authentication system, allowing a user to explore his/her Facebook-friend's playlists and share music discoveries with them.
See also
Similar websites
Songza
Slacker Radio
Last.fm
Jamendo
MeeMix
Deezer
Related concepts
Faceted search
Daemon |
https://en.wikipedia.org/wiki/Margaret%20A.%20Dix | Margaret Ann Dix (born 19 May 1939) is a Jersey-born Guatemalan botanist. In 1972, she founded the Center for Environmental Studies and Biodiversity () at the .
Biography
Born on Jersey in the Channel Islands, she attended London University where she graduated in biology in 1962. She received her masters in zoology from Mount Holyoke College, Massachchusetts, in 1964. From 1964 to 1968, she studied entomology, ecology and animal behaviour at Harvard University under E. O. Wilson. While studying at Harvard, she was required to spend two years abroad. At the end of 1972, together with her American husband, Michael W. Dix, she decided to go to Guatemala where there was an opportunity to found a biology department at the University of the Valley. In 1977, she was appointed director of the department, a post she maintained until 2002. She is still associated with biological and environmental research at the university and continues to be active in the field.
Dix is a recognized taxonomist, especially in the area of Guatemalan orchids. Her Orchids of Guatemala: A revised annotated checklist (2000) based on extensive field collections covers 734 taxa, including 207 new records.
Selected publications
Journal articles
. 2007. Integrated approaches to orchid conservation in Guatemala: past, present and future, opportunities and challenges. Lankesteriana 7 (1–2): 266–268
. 2006. Diversity, distribution, ecology and economic importance of Guatemalan orchids, pp. 187–198 in E. Cano (ed.) Biodiversidad de Guatemala. Volumen 1. Universidad del Valle
. 2003. Rhynchostele bictoniensis: cambios en abundancia y éxito de polinización entre 1992 y 2002. Lankesteriana 3 (7 ): 98
. 2003. Impacto de Hydrilla verticillata. Fase 1. Datos biológicos e indicadores básicos de ictiofauna en el lago de Izabal. Informe final Proyecto AGROCYT
. 2003. Polinización de orquídeas en Guatemala: los polinizadores, el estado natural de sus poblaciones y las implicaciones para las especies polin |
https://en.wikipedia.org/wiki/Penn%20Genome%20Frontiers%20Institute | The Penn Genome Frontiers Institute, previously known as the Penn Genomics Institute, was established in January 2001 to provide a focus for all aspects of and participants in the genomics community at University of Pennsylvania, Children's Hospital of Philadelphia (CHOP) and the Wistar Institute. |
https://en.wikipedia.org/wiki/Homomorphic%20signatures%20for%20network%20coding | Network coding has been shown to optimally use bandwidth in a network, maximizing information flow but the scheme is very inherently vulnerable to pollution attacks by malicious nodes in the network. A node injecting garbage can quickly affect many receivers. The pollution of network packets spreads quickly since the output of (even an) honest node is corrupted if at least one of the incoming packets is corrupted.
An attacker can easily corrupt a packet even if it is encrypted by either forging the signature or by producing a collision under the hash function. This will give an attacker access to the packets and the ability to corrupt them. Denis Charles, Kamal Jain and Kristin Lauter designed a new homomorphic encryption signature scheme for use with network coding to prevent pollution attacks.
The homomorphic property of the signatures allows nodes to sign any linear combination of the incoming packets without contacting the signing authority. In this scheme it is computationally infeasible for a node to sign a linear combination of the packets without disclosing what linear combination was used in the generation of the packet. Furthermore, we can prove that the signature scheme is secure under well known cryptographic assumptions of the hardness of the discrete logarithm problem and the computational Elliptic curve Diffie–Hellman.
Network coding
Let be a directed graph where is a set, whose elements are called vertices or nodes, and is a set of ordered pairs of vertices, called arcs, directed edges, or arrows. A source wants to transmit a file to a set of the vertices. One chooses a vector space (say of dimension ), where is a prime, and views the data to be transmitted as a bunch of vectors . The source then creates the augmented vectors by setting where is the -th coordinate of the vector . There are zeros before the first '1' appears in . One can assume without loss of generality that the vectors are linearly independent. We denote the linear s |
https://en.wikipedia.org/wiki/Electrochemical%20potential | In electrochemistry, the electrochemical potential (ECP), , is a thermodynamic measure of chemical potential that does not omit the energy contribution of electrostatics. Electrochemical potential is expressed in the unit of J/mol.
Introduction
Each chemical species (for example, "water molecules", "sodium ions", "electrons", etc.) has an electrochemical potential (a quantity with units of energy) at any given point in space, which represents how easy or difficult it is to add more of that species to that location. If possible, a species will move from areas with higher electrochemical potential to areas with lower electrochemical potential; in equilibrium, the electrochemical potential will be constant everywhere for each species (it may have a different value for different species). For example, if a glass of water has sodium ions (Na+) dissolved uniformly in it, and an electric field is applied across the water, then the sodium ions will tend to get pulled by the electric field towards one side. We say the ions have electric potential energy, and are moving to lower their potential energy. Likewise, if a glass of water has a lot of dissolved sugar on one side and none on the other side, each sugar molecule will randomly diffuse around the water, until there is equal concentration of sugar everywhere. We say that the sugar molecules have a "chemical potential", which is higher in the high-concentration areas, and the molecules move to lower their chemical potential. These two examples show that an electrical potential and a chemical potential can both give the same result: A redistribution of the chemical species. Therefore, it makes sense to combine them into a single "potential", the electrochemical potential, which can directly give the net redistribution taking both into account.
It is (in principle) easy to measure whether or not two regions (for example, two glasses of water) have the same electrochemical potential for a certain chemical species (for examp |
https://en.wikipedia.org/wiki/Local%20criterion%20for%20flatness | In algebra, the local criterion for flatness gives conditions one can check to show flatness of a module.
Statement
Given a commutative ring A, an ideal I and an A-module M, suppose either
A is a Noetherian ring and M is idealwise separated for I: for every ideal , (for example, this is the case when A is a Noetherian local ring, I its maximal ideal and M finitely generated),
or
I is nilpotent.
Then the following are equivalent:
The assumption that “A is a Noetherian ring” is used to invoke the Artin–Rees lemma and can be weakened; see
Proof
Following SGA 1, Exposé IV, we first prove a few lemmas, which are interesting themselves. (See also this blog post by Akhil Mathew for a proof of a special case.)
Proof: The equivalence of the first two can be seen by studying the Tor spectral sequence. Here is a direct proof: if 1. is valid and is an injection of -modules with cokernel C, then, as A-modules,
.
Since and the same for , this proves 2. Conversely, considering where F is B-free, we get:
.
Here, the last map is injective by flatness and that gives us 1. To see the "Moreover" part, if 1. is valid, then and so
By descending induction, this implies 3. The converse is trivial.
Proof: The assumption implies that and so, since tensor product commutes with base extension,
.
For the second part, let denote the exact sequence and . Consider the exact sequence of complexes:
Then (it is so for large and then use descending induction). 3. of Lemma 1 then implies that is flat.
Proof of the main statement.
: If is nilpotent, then, by Lemma 1, and is flat over . Thus, assume that the first assumption is valid. Let be an ideal and we shall show is injective. For an integer , consider the exact sequence
Since by Lemma 1 (note kills ), tensoring the above with , we get:
.
Tensoring with , we also have:
We combine the two to get the exact sequence:
Now, if is in the kernel of , then, a fortiori, is in . By the Artin–Rees lemma, given , we can fin |
https://en.wikipedia.org/wiki/Vesicle%20fusion | Vesicle fusion is the merging of a vesicle with other vesicles or a part of a cell membrane. In the latter case, it is the end stage of secretion from secretory vesicles, where their contents are expelled from the cell through exocytosis. Vesicles can also fuse with other target cell compartments, such as a lysosome. Exocytosis occurs when secretory vesicles transiently dock and fuse at the base of cup-shaped structures at the cell plasma membrane called porosome, the universal secretory machinery in cells. Vesicle fusion may depend on SNARE proteins in the presence of increased intracellular calcium (Ca2+) concentration.
Triggers
Stimuli that trigger vesicle fusion act by increasing intracellular Ca2+.
Synaptic vesicles commit vesicle fusion by a nerve impulse reaching the synapse, activating voltage-dependent calcium channels that cause influx of Ca2+ into the cell.
In the endocrine system, many hormones are released by their releasing hormones binding to G protein coupled receptors coupled to the Gq alpha subunit, activating the IP3/DAG pathway to increase Ca2+. Examples of this mechanism include:
Gonadotropin releasing hormone
Thyrotropin releasing hormone
Growth hormone releasing hormone (minor pathway - main one is cAMP dependent pathway)
Model systems
Model systems consisting of a single phospholipid or a mixture have been studied by physical chemists. Cardiolipin is found mainly in mitochondrial membranes, and calcium ions play an important role in the respiratory processes mediated by the mitochondrion. The forces involved have been postulated to explain this process in terms of nucleation for agglomeration of smaller supramolecular entities or phase changes in the structure of the biomembranes.
Mechanisms
Synaptic cleft fusion
In synaptic vesicle fusion, the vesicle must be within a few nanometers of the target membrane for the fusion process to begin. This closeness allows the cell membrane and the vesicle to exchange lipids which is mediated by |
https://en.wikipedia.org/wiki/ANSI/ASA%20S1.1-2013 | ANSI/ASA S1.1-2013, published by the American National Standards Institute (ANSI), is the current American National Standard on Acoustical Terminology. ANSI S1.1 was first published in 1960 and has its roots in a 1942 standard published by the American Standards Association, the predecessor of ANSI. It includes the following sections
Scope
General
Levels
Oscillation, vibration, and shock
Transmission and propagation
Transducers and linear systems
Acoustical apparatus and instruments
Underwater acoustics
Sonics and ultrasonic testing
Architectural acoustics
Physiological and psychological acoustics
Musical acoustics
External links
ANSI/ASA S1.1 & S3.20 Standard Acoustical & Bioacoustical Terminology Database
ANSI website |
https://en.wikipedia.org/wiki/Leptospirillum%20ferriphilum | Leptospirillum ferriphilum is an iron-oxidising bacterium. It is one of the species responsible for the generation of acid mine drainage. It is of particular relevance in South African commercial biooxidation tanks operating at 40 °C. |
https://en.wikipedia.org/wiki/Process%20corners | In semiconductor manufacturing, a process corner is an example of a design-of-experiments (DoE) technique that refers to a variation of fabrication parameters used in applying an integrated circuit design to a semiconductor wafer. Process corners represent the extremes of these parameter variations within which a circuit that has been etched onto the wafer must function correctly. A circuit running on devices fabricated at these process corners may run slower or faster than specified and at lower or higher temperatures and voltages, but if the circuit does not function at all at any of these process extremes the design is considered to have inadequate design margin.
To verify the robustness of an integrated circuit design, semiconductor manufacturers will fabricate corner lots, which are groups of wafers that have had process parameters adjusted according to these extremes, and will then test the devices made from these special wafers at varying increments of environmental conditions, such as voltage, clock frequency, and temperature, applied in combination (two or sometimes all three together) in a process called characterization. The results of these tests are plotted using a graphing technique known as a shmoo plot that indicates clearly the boundary limit beyond which a device begins to fail for a given combination of these environmental conditions.
Corner-lot analysis is most effective in digital electronics because of the direct effect of process variations on the speed of transistor switching during transitions from one logic state to another, which is not relevant for analog circuits, such as amplifiers.
Significance to digital electronics
In Very-Large-Scale Integration (VLSI) integrated circuit microprocessor design and semiconductor fabrication, a process corner represents a three or six sigma variation from nominal doping concentrations (and other parameters) in transistors on a silicon wafer. This variation can cause significant changes in the dut |
https://en.wikipedia.org/wiki/Resting%20state%20fMRI | Resting state fMRI (rs-fMRI or R-fMRI) is a method of functional magnetic resonance imaging (fMRI) that is used in brain mapping to evaluate regional interactions that occur in a resting or task-negative state, when an explicit task is not being performed. A number of resting-state brain networks have been identified, one of which is the default mode network. These brain networks are observed through changes in blood flow in the brain which creates what is referred to as a blood-oxygen-level dependent (BOLD) signal that can be measured using fMRI.
Because brain activity is intrinsic, present even in the absence of an externally prompted task, any brain region will have spontaneous fluctuations in BOLD signal. The resting state approach is useful to explore the brain's functional organization and to examine if it is altered in neurological or mental disorders. Because of the resting state aspect of this imaging, data can be collected from a range of patient groups including people with intellectual disabilities, pediatric groups, and even those that are unconscious. Resting-state functional connectivity research has revealed a number of networks which are consistently found in healthy subjects, different stages of consciousness and across species, and represent specific patterns of synchronous activity.
Basics of resting state fMRI
Functional magnetic resonance imaging (functional MRI or fMRI) is a specific magnetic resonance imaging (MRI) procedure that measures brain activity by detecting associated changes in blood flow. More specifically, brain activity is measured through low frequency BOLD signal in the brain.
The procedure is similar to MRI but uses the change in magnetization between oxygen-rich and oxygen-poor blood as its basic measure. This measure is frequently corrupted by noise from various sources and hence statistical procedures are used to extract the underlying signal. The resulting brain activation can be presented graphically by color-coding |
https://en.wikipedia.org/wiki/Otto%20Neurath | Otto Karl Wilhelm Neurath (; 10 December 1882 – 22 December 1945) was an Austrian-born philosopher of science, sociologist, and political economist. He was also the inventor of the ISOTYPE method of pictorial statistics and an innovator in museum practice. Before he fled his native country in 1934, Neurath was one of the leading figures of the Vienna Circle.
Early life
Neurath was born in Vienna, the son of Wilhelm Neurath (1840–1901), a well-known political economist at the time. Otto's mother was a Protestant, and he would also become one. Helene Migerka was his cousin. He studied mathematics and physics at the University of Vienna (he formally enrolled for classes only for two semesters in 1902–3). In 1906, he gained his PhD in the department of Political Science and Statistics at the University of Berlin with a thesis entitled Zur Anschauung der Antike über Handel, Gewerbe und Landwirtschaft (On the Conceptions in Antiquity of Trade, Commerce and Agriculture).
He married Anna Schapire in 1907, who died in 1911 while bearing their son, Paul, and then married a close friend, the mathematician and philosopher Olga Hahn. Perhaps because of his second wife's blindness and then because of the outbreak of war, Paul was sent to a children's home outside Vienna, where Neurath's mother lived, and returned to live with both of his parents when he was nine years old.
Career in Vienna
Neurath taught political economy at the New Vienna Commercial Academy in Vienna until war broke out. Subsequently, he directed the Department of War Economy in the War Ministry. In 1917, he completed his habilitation thesis Die Kriegswirtschaftslehre und ihre Bedeutung für die Zukunft (War Economics and Their Importance for the Future) at Heidelberg University. In 1918, he became director of the Deutsches Kriegswirtschaftsmuseum (German Museum of War Economy, later the "Deutsches Wirtschaftsmuseum") at Leipzig. Here he worked with Wolfgang Schumann, known from the Dürerbund for which Neurath |
https://en.wikipedia.org/wiki/Voigt%E2%80%93Thomson%20law | Voigt–Thomson law describes anisotropic magnetoresistance effect in a thin film strip as a relationship between the electric resistivity and the direction of electric current:
where:
is the angle of direction of current in relation to the direction of magnetic field
is the initial resistivity
is the change of resistivity (proportional to MR ratio)
The equation can also be expressed as:
where:
is the parallel component of resistivity
is the perpendicular component |
https://en.wikipedia.org/wiki/RCA%20CDP1861 | The RCA CDP1861 was an integrated circuit Video Display Controller, released by the Radio Corporation of America (RCA) in the mid-1970s as a support chip for the RCA 1802 microprocessor. The chip cost in 1977 amounted to less than US$20.
History
The CDP1861 was manufactured in a low-power CMOS technology, came in a 24-pin DIP (Dual in-line package), and required a minimum of external components to work. In 1802-based microcomputers, the CDP1861 (for the NTSC video format, CDP1864 variant for PAL), used the 1802's built-in DMA controller to display black and white (monochrome) bitmapped graphics on standard TV screens. The CDP1861 was also known as the Pixie graphics system, display, chip, and video generator, especially when used with the COSMAC ELF microcomputer. Other known chip markings for the 1861 are TA10171, TA10171V1 and a TA10171X, which were early designations for "pre-qualification engineering samples" and "preliminary part numbers", although they have been found in production RCA Studio II game consoles and Netronics Elf microcomputers. The CDP1861 was also used in the Telmac 1800 and Oscom Nano microcomputers.
Specifications
The 1861 chip could display 64 pixels horizontally and 128 pixels vertically, though by reloading the 1802's R0 DMA (direct memory access) register via the required 1802 software controller program and interrupt service routine, the resolution could be reduced to 64×64 or 64×32 to use less memory than the 1024 bytes needed for the highest resolution (with each monochrome pixel occupying one bit) or to display square pixels. A resolution of 64×32 created square pixels and used 256 bytes of memory (2K bits). This was the usual resolution for the Chip-8 game programming system. Since the video graphics frame buffer was often similar or equal in size to the memory size, it was not unusual to display your program/data on the screen allowing you to watch the computer "think" (i.e. process its data). Programs which ran amok and accidenta |
https://en.wikipedia.org/wiki/B-box%20zinc%20finger | In molecular biology the B-box-type zinc finger domain is a short protein domain of around 40 amino acid residues in length. B-box zinc fingers can be divided into two groups, where types 1 and 2 B-box domains differ in their consensus sequence and in the spacing of the 7-8 zinc-binding residues. Several proteins contain both types 1 and 2 B-boxes, suggesting some level of cooperativity between these two domains.
Occurrence
B-box domains are found in over 1500 proteins from a variety of organisms. They are found in TRIM (tripartite motif) proteins that consist of an N-terminal RING finger (originally called an A-box), followed by 1-2 B-box domains and a coiled-coil domain (also called RBCC for Ring, B-box, Coiled-Coil). TRIM proteins contain a type 2 B-box domain, and may also contain a type 1 B-box. In proteins that do not contain RING or coiled-coil domains, the B-box domain is primarily type 2. Many type 2 B-box proteins are involved in ubiquitinylation. Proteins containing a B-box zinc finger domain include transcription factors, ribonucleoproteins and proto-oncoproteins; for example, MID1, MID2, TRIM9, TNL, TRIM36, TRIM63, TRIFIC, NCL1 and CONSTANS-like proteins.
The microtubule-associated E3 ligase MID1 (EC) contains a type 1 B-box zinc finger domain. MID1 specifically binds Alpha-4, which in turn recruits the catalytic subunit of phosphatase 2A (PP2Ac). This complex is required for targeting of PP2Ac for proteasome-mediated degradation. The MID1 B-box coordinates two zinc ions and adopts a beta/beta/alpha cross-brace structure similar to that of ZZ, PHD, RING and FYVE zinc fingers.
Homologs
Prokaryotic homologs of the domain are present in several bacterial lineages and methanogenic archaea, and often show fusions to peptidase domains such as the rhomboid-like serine peptidase, and Zn-dependent metallopeptidase. Other versions typically contain transmembrane helices and might also show fusions to domains such as DNAJ, FHA, SH3, WD40 and tetratricopeptide r |
https://en.wikipedia.org/wiki/MT6235 | The MT6235 is a processor used in many Chinese cellular phones (eg. ZTE). It is a member of the MT62xx series of processors by MediaTek.
MediaTek-based Chinese cell phones often come with features not common to North American phones, such as analog television viewing and recording. While these phones have vastly different builds and configurations, they all run Mediatek's proprietary operating system based on the Nucleus RTOS.
The MT6235 is a specialized processor design containing both an ARM926EJ-S RISC CPU running at frequencies between 26/52/104 and 208 MHz and a digital signal processor (DSP).
Subsystems
Microcontroller Unit (MCU) Subsystem: includes an ARM926EJ-S RISC processor and its accompanying memory management and interrupt handling logics;
Digital Signal Processor (DSP) Subsystem: includes a DSP and its accompanying memory, memory controller, and interrupt controller;
MCU/DSP Interface: the junction at which the MCU and the DSP exchange hardware and software information;
Microcontroller Peripherals: includes all user interface modules and RF control interface modules;
Microcontroller Coprocessors: runs computing-intensive processes in place of the Microcontroller;
DSP Peripherals: hardware accelerators for GSM/GPRS/EDGE channel codec;
Multi-media Subsystem: integrates several advanced accelerators to support multi-media applications;
Voice Front End: the data path for converting analog speech to and from digital speech;
Audio Front End: the data path for converting stereo audio from an audio source;
Baseband Front End: the data path for converting a digital signal to and from an analog signal from the RF modules;
Timing Generator: generates the control signals related to the TDMA frame timing; and,
Power, Reset and Clock Subsystem: manages the power, reset, and clock distribution inside MT6235.
Sources
http://ryan.com.br/smf/index.php?topic=481.75;wap2
http://blog.csdn.net/sergeycao/archive/2008/08/26/2832568.aspx
M |
https://en.wikipedia.org/wiki/Quantum%20wire | In mesoscopic physics, a quantum wire is an electrically conducting wire in which quantum effects influence the transport properties. Usually such effects appear in the dimension of nanometers, so they are also referred to as nanowires.
Quantum effects
If the diameter of a wire is sufficiently small, electrons will experience quantum confinement in the transverse direction. As a result, their transverse energy will be limited to a series of discrete values. One consequence of this quantization is that the classical formula for calculating the electrical resistance of a wire,
is not valid for quantum wires (where is the material's resistivity, is the length, and is the cross-sectional area of the wire).
Instead, an exact calculation of the transverse energies of the confined electrons has to be performed to calculate a wire's resistance. Following from the quantization of electron energy, the electrical conductance (the inverse of the resistance) is found to be quantized in multiples of , where is the electron charge and is the Planck constant. The factor of two arises from spin degeneracy. A single ballistic quantum channel (i.e. with no internal scattering) has a conductance equal to this quantum of conductance. The conductance is lower than this value in the presence of internal scattering.
The importance of the quantization is inversely proportional to the diameter of the nanowire for a given material. From material to material, it is dependent on the electronic properties, especially on the effective mass of the electrons. Physically, this means that it will depend on how conduction electrons interact with the atoms within a given material. In practice, semiconductors can show clear conductance quantization for large wire transverse dimensions (~100 nm) because the electronic modes due to confinement are spatially extended. As a result, their Fermi wavelengths are large and thus they have low energy separations. This means that they can only be resolv |
https://en.wikipedia.org/wiki/Single-crossing%20condition | In monotone comparative statics, the single-crossing condition or single-crossing property refers to a condition where the relationship between two or more functions is such that they will only cross once. For example, a mean-preserving spread will result in an altered probability distribution whose cumulative distribution function will intersect with the original's only once.
The single-crossing condition was posited in Samuel Karlin's 1968 monograph 'Total Positivity'. It was later used by Peter Diamond, Joseph Stiglitz, and Susan Athey, in studying the economics of uncertainty.
The single-crossing condition is also used in applications where there are a few agents or types of agents that have preferences over an ordered set. Such situations appear often in information economics, contract theory, social choice and political economics, among other fields.
Example using cumulative distribution functions
Cumulative distribution functions F and G satisfy the single-crossing condition if there exists a such that
and
;
that is, function crosses the x-axis at most once, in which case it does so from below.
This property can be extended to two or more variables. Given x and t, for all x'>x, t'>t,
and
.
This condition could be interpreted as saying that for x'>x, the function g(t)=F(x',t)-F(x,t) crosses the horizontal axis at most once, and from below. The condition is not symmetric in the variables (i.e., we cannot switch x and t in the definition; the necessary inequality in the first argument is weak, while the inequality in the second argument is strict).
Use in Social Choice
In the study of social choice, the single-crossing condition is a condition on preferences. It is especially useful because utility functions are generally increasing (i.e. the assumption that an agent will prefer or at least consider equivalent two dollars to one dollar is unobjectionable).
Specifically, a set of agents with some unidimensional characteristic and preferences |
https://en.wikipedia.org/wiki/Fibularis%20tertius | In human anatomy, the fibularis tertius (also known as the peroneus tertius) is a muscle in the anterior compartment of the leg. It acts to tilt the sole of the foot away from the midline of the body (eversion) and to pull the foot upward toward the body (dorsiflexion).
Structure
The fibularis tertius arises from the lower third of the front surface of the fibula, the lower part of the interosseous membrane, and septum, or connective tissue, between it and the fibularis brevis. The septum is sometimes called the intermuscular septum of Otto.
The muscle passes downward and ends in a tendon that passes under the superior extensor retinaculum and the inferior extensor retinaculum of the foot in the same canal as the extensor digitorum longus muscle. It may be mistaken as a fifth tendon of the extensor digitorum longus. The tendon inserts into the medial part of the posterior surface of the shaft of the fifth metatarsal bone.
The fibularis tertius is supplied by the deep fibular nerve. In rare cases, it may also be supplied by the common fibular nerve. This is unlike the other fibularis muscles, which are located in the lateral compartment of the leg and are supplied by the superficial fibular nerve, since the fibularis tertius is found in the anterior compartment of the leg.
The fibularis tertius may be absent in humans. It may be absent in as few as 5% of people, or as many as 72%, depending on the population surveyed. It is rarely found in other primates, which is one reason its function has been linked to efficient bipedalism.
Function
As a weak dorsiflexor of the ankle joint, the fibularis tertius assists in pulling the foot upward toward the body. It also assists in tilting the sole of the foot away from midline of the body at the ankle (eversion). It is likely to be helpful though not essential in bipedal walking.
Clinical significance
The fibularis tertius may be involved in ankle injuries and may rupture. This is caused by hyperextension.
The fibular |
https://en.wikipedia.org/wiki/100 | 100 or one hundred (Roman numeral: C) is the natural number following 99 and preceding 101.
In mathematics
100 is the square of 10 (in scientific notation it is written as 102). The standard SI prefix for a hundred is "hecto-".
100 is the basis of percentages (per cent meaning "per hundred" in Latin), with 100% being a full amount.
100 is a Harshad number in decimal, and also in base-four, a base in-which it is also a self-descriptive number.
100 is the sum of the first nine prime numbers, from 2 through 23. It is also divisible by the number of primes below it, 25.
100 cannot be expressed as the difference between any integer and the total of coprimes below it, making it a noncototient.
100 has a reduced totient of 20, and an Euler totient of 40. A totient value of 100 is obtained from four numbers: 101, 125, 202, and 250.
100 can be expressed as a sum of some of its divisors, making it a semiperfect number. The geometric mean of its nine divisors is 10.
100 is the sum of the cubes of the first four positive integers (100 = 13 + 23 + 33 + 43). This is related by Nicomachus's theorem to the fact that 100 also equals the square of the sum of the first four positive integers: .
100 = 26 + 62, thus 100 is the seventh Leyland number. 100 is also the seventeenth Erdős–Woods number, and the fourth 18-gonal number.
The 100th prime number is 541, which returns for the Mertens function. It is the 10th star number (whose digit sum also adds to 10 in decimal).
There are exactly 100 prime numbers in base-ten whose digits are in strictly ascending order (e.g. 239, 2357 etc.). The last such prime number is 23456789, which contains eight consecutive integers as digits.
In science
One hundred is the atomic number of fermium, an actinide and the last of the heavy metals that can be created through neutron bombardment.
On the Celsius scale, 100 degrees is the boiling temperature of pure water at sea level.
The Kármán line lies at an altitude of 100 kilometres above th |
https://en.wikipedia.org/wiki/List%20of%20geophysicists | This is a list of geophysicists, people who made notable contributions to geophysics, whether or not geophysics was their primary field. These include historical figures who laid the foundations for the field of geophysics. More recently, some of the top awards for geophysicists are the Vetlesen Prize (intended to be the equivalent of a Nobel Prize for geology or geophysics); the William Bowie Medal (the top award of the American Geophysical Union); the Maurice Ewing Medal (the top award of the Society of Exploration Geophysicists); and the Crafoord Prize for geosciences. Some geophysicists have also won more general prizes such as the Nobel Prize and the Kyoto Prize.
A
Leason Adams (American, 1887–1969) – high pressure mineral physics
Thomas J Ahrens (American, 1936–2010) – experimental methods for modeling hypervelocity impacts and materials in the Earth's core and mantle
Hannes Alfvén (Swedish, 1908–1995) – Alfvén waves, magnetohydrodynamics of magnetosphere; Nobel Prize in Physics
Giuseppina Aliverti (Italian, 1894–1982), geophysicist remembered for developing the Aliverti-Lovera method of measuring the radioactivity of water
Keiiti Aki (Japanese-American, 1930–2005) – seismology; William Bowie Medal
Claude Allègre (French, 1937– ) Crafoord Prize
Don L. Anderson (American, 1933–2014) – seismology and Earth's interior (including the Preliminary reference Earth model); Crafoord Prize
Nigel Anstey (British, 1927– ) – exploration geophysicist ; Maurice Ewing Medal (SEG)
Tanya Atwater (American, 1942– ) – plate tectonic history of North America
B
George Edward Backus (American, 1930– ) – geophysical mathematician, development of geophysical inverse methods; contributions to dynamo theory
Milo Backus (American, 1932–2018) – exploration geophysicist; practical 3D exploration; Maurice_Ewing_Medal (SEG)
Peter Barlow (English, 1776–1862) – experimental and observational studies of terrestrial magnetism, Copley Medal
Anthony R. Barringer (Canadian/American, |
https://en.wikipedia.org/wiki/Horse%20cloning | Horse cloning is the process of obtaining a horse with genes identical to that of another horse, using an artificial fertilization technique. Interest in this technique began in the 1980s. The Haflinger foal Prometea, the first living cloned horse, was obtained in 2003 in an Italian laboratory. Over the years, the technique has improved. It is mainly used on high-performance but castrated or infertile animals, for reproductive cloning. These horses are then used as breeding stock. Horse cloning is only mastered by a handful of laboratories worldwide, notably in France, Argentina, North America and China. The technique is limited by the fact that some differences remain between the original and its clone, due to the influence of mitochondrial DNA.
Reproductive cloning of the Pieraz and Quidam de Revel horses began in 2005. The International Federation for Equestrian Sports (FEI by its acronym in French) decided to ban clones from competition in 2007, before authorizing them in 2012. A few clones are used in equestrian sports, winning major titles such as the Argentine polo championship in 2013. The majority of studbooks and associations for the various horse breeds refuse to accept clones, with the European Union completely banning the trade in cloned animals in 2015. Nevertheless, the number of cloned horses is growing every year. The practice is highly controversial, particularly for bioethical reasons, since it involves a high failure rate on embryos. It also raises questions about the management of horses' genetic diversity, the future of the horse breeding profession, and the outbreak of new genetic disorders or fraud.
History
Horse cloning has undergone a rapid qualitative and quantitative evolution. While Italian professor Cesare Galli believes that horse cloning has aroused less interest than that of other large mammals, other scientists believe that the high commercial value attained by some horses has created immediate interest, unlike in the case of le |
https://en.wikipedia.org/wiki/MHC%20class%20III | MHC class III is a group of proteins belonging the class of major histocompatibility complex (MHC). Unlike other MHC types such as MHC class I and MHC class II, of which their structure and functions in immune response are well defined, MHC class III are poorly defined structurally and functionally. They are not involved in antigen binding (the process called antigen presentation, a classic function of MHC proteins). Only few of them are actually involved in immunity while many are signalling molecules in other cell communications. They are mainly known from their genes because their gene cluster is present between those of class I and class II. The gene cluster was discovered when genes (specifically those of complement components C2, C4, and factor B) were found in between class I and class II genes on the short (p) arm of human chromosome 6. It was later found that it contains many genes for different signalling molecules such as tumour necrosis factors (TNFs) and heat shock proteins. More than 60 MHC class III genes are described, which is about 28% of the total MHC genes (224). The region previously considered within MHC class III gene cluster that contains genes for TNFs is now known as MHC class IV or inflammatory region.
In contrast to other MHC proteins, MHC class III proteins are produced by liver cells (hepatocytes) and special white blood cells (macrophages), among others.
Gene structure
MHC class III genes are located on chromosome 6 (6p21.3) in humans. It covers 700 kb and contains 61 genes. The gene cluster is the most gene-dense region of the human genome. They are basically similar with those of other animals. The functions of many genes are yet unknown. Many retroelements such as human endogenous retrovirus (HERV) and Alu elements are located in the cluster. The region containing genes STK19(G11)/C4/Z/CYP21/X/Y, varying in size from 142 to 214 kb, is known as the most complex gene cluster in the human genome.
Diversity
MHC class III genes are |
https://en.wikipedia.org/wiki/Dynamic%20scaling | Dynamic scaling (sometimes known as Family–Vicsek scaling) is a litmus test that shows whether an evolving system exhibits self-similarity. In general a function is said to exhibit dynamic scaling if it satisfies:
Here the exponent is fixed by the dimensional requirement . The numerical value of should remain invariant despite the unit of measurement of is changed by some factor since is a dimensionless quantity.
Many of these systems evolve in a self-similar fashion in the sense that data obtained from the snapshot at any fixed time is similar to the respective data taken from the snapshot of any earlier or later time. That is, the system is similar to itself at different times. The litmus test of such self-similarity is provided by the dynamic scaling.
History
The term "dynamic scaling" as one of the essential concepts to describe the dynamics of critical phenomena seems to originate in the seminal paper of Pierre Hohenberg and Bertrand Halperin (1977), namely they suggested "[...] that the wave vector- and frequencydependent susceptibility of a ferromagnet near its Curie point may be expressed as a function independent of provided that the length and frequency scales, as well as the magnetization and magnetic field, are rescaled by appropriate powers of .
Later Tamás Vicsek and Fereydoon Family proposed the idea of dynamic scaling in the context of diffusion-limited aggregation (DLA) of clusters in two dimensions. The form of their proposal for dynamic scaling was:
where the exponents satisfy the following relation:
Test
In such systems we can define a certain time-dependent stochastic variable . We are interested in computing the probability distribution of at various instants of time i.e. . The numerical value of and the typical or mean value of generally changes over time. The question is: what happens to the corresponding dimensionless variables? If the numerical values of the dimensional quantities change, but corresponding dimensionless qua |
https://en.wikipedia.org/wiki/Landau%E2%80%93Ramanujan%20constant | In mathematics and the field of number theory, the Landau–Ramanujan constant is the positive real number b that occurs in a theorem proved by Edmund Landau in 1908, stating that for large , the number of positive integers below that are the sum of two square numbers behaves asymptotically as
This constant b was rediscovered in 1913 by Srinivasa Ramanujan, in the first letter he wrote to G.H. Hardy.
Sums of two squares
By the sum of two squares theorem, the numbers that can be expressed as a sum of two squares of integers are the ones for which each prime number congruent to 3 mod 4 appears with an even exponent in their prime factorization. For instance, 45 = 9 + 36 is a sum of two squares; in its prime factorization, 32 × 5, the prime 3 appears with an even exponent, and the prime 5 is congruent to 1 mod 4, so its exponent can be odd.
Landau's theorem states that if is the number of positive integers less than that are the sum of two squares, then
,
where is the Landau–Ramanujan constant.
The Landau-Ramanujan constant can also be written as an infinite product:
History
This constant was stated by Landau in the limit form above; Ramanujan instead approximated as an integral, with the same constant of proportionality, and with a slowly growing error term. |
https://en.wikipedia.org/wiki/T-MOS%20thermal%20sensor | TMOS is a new type of thermal sensor consisting in a micromachined thermally isolated transistor fabricated using CMOS-SOI(Silicon on Insulator) MEMS(Micro electro-mechanical system) technology. It has been developed in the last decade by the Technion - Israel Institute of Technology. A thermal sensor is a device able to detect the thermal radiation emitted by an object located in the FOV(Field Of View) of the sensor. Infrared radiation ( IR ) striking the sensor produces a change in the temperature of the device that as a consequence generates an electric output signal proportional to the incident IR power. The sensor is able to measure the temperature of the object radiating thanks to the information contained in the impinging radiation, exploiting in this sense Stefan - Boltzmann law. TMOS detector has two important characteristics that make it different from others: it's an active and uncooled sensor.
Fabrication process
A TMOS detector consists in a mosaic structure composed of several sub-pixels, which are electrically connected in parallel or in series or in a mixed combination, and are thermally isolated. In each sub-pixels the sensitive element is the TMOS sensor, that is suspended in vacuum, fabricated in CMOS - SOI technology and dry released. The mosaic structure includes: the pixel frame, the suspended transistor, that absorbs IR radiation and that could also be embedded in an absorbing IR membrane which determine the thermal capacitance of the sensor, and two folding arms that determine the sensor thermal conductance.
TMOS fabrication is based on built - in masks and dry bulk micromachining. In TMOS fabrication to the standard CMOS - SOI technology, used to produce MOS transistor, is added a MEMS post process necessary to realize the folded arms and the suspension of the transistor. In standard CMOS process there are several metallization layers. In TMOS production the upper ones, made in aluminum or copper, are used as built - in masks. Both metal |
https://en.wikipedia.org/wiki/Viable%20but%20nonculturable | Viable but nonculturable (VBNC) bacteria refers as to bacteria that are in a state of very low metabolic activity and do not divide, but are alive and have the ability to become culturable once resuscitated.
Bacteria in a VBNC state cannot grow on standard growth media, though flow cytometry can measure the viability of the bacteria. Bacteria can enter the VBNC state as a response to stress, due to adverse nutrient, temperature, osmotic, oxygen, and light conditions. The cells that are in the VBNC state are morphologically smaller, and demonstrate reduced nutrient transport, rate of respiration, and synthesis of macromolecules. Sometimes, VBNC bacteria can remain in that state for over a year. It has been shown that numerous pathogens and non-pathogens can enter the VBNC state, which therefore has significant implications in pathogenesis, bioremediation, and other branches of microbiology.
The existence of the VBNC state is controversial. The validity and interpretation of the assays to determine the VBNC state have been questioned.
VBNC pathogens
Species known to enter a VBNC state:
E.M.S
Aeromonas salmonicida
Agrobacterium tumefaciens
Burkholderia cepacia
Burkholderia pseudomallei
Brettanomyces bruxellensis
Campylobacter coli
Campylobacter jejuni
Campylobacter lari
Cytophaga allerginae
Enterobacter aerogenes
Enterobacter cloacae
Enterococcus faecalis
Enterococcus hirae
Enterococcus faecium
Erwinia amylovora
Escherichia coli (including EHEC)
Francisella tularensis
Helicobacter pylori
Klebsiella aerogenes
Klebsiella pneumoniae
Klebsiella planticola
Legionella pneumophila
Listeria monocytogenes
Micrococcus luteus
Mycobacterium tuberculosis
Mycobacterium smegmatis
Pasteurella piscicida
Pseudomonas aeruginosa
Pseudomonas syringae
Pseudomonas putida KT2440
Ralstonia solanacearum
Rhizobium leguminosarum
Rhizobium meliloti
Salmonella enterica
Salmonella Typhi
Salmonella Typhimurium
Serratia marcescens
Shigella dysenteriae
Shigella flexneri
Shigella sonnei
Streptococc |
https://en.wikipedia.org/wiki/Cylinder%20stress | In mechanics, a cylinder stress is a stress distribution with rotational symmetry; that is, which remains unchanged if the stressed object is rotated about some fixed axis.
Cylinder stress patterns include:
circumferential stress, or hoop stress, a normal stress in the tangential (azimuth) direction.
axial stress, a normal stress parallel to the axis of cylindrical symmetry.
radial stress, a normal stress in directions coplanar with but perpendicular to the symmetry axis.
These three principal stresses- hoop, longitudinal, and radial can be calculated analytically using a mutually perpendicular tri-axial stress system.
The classical example (and namesake) of hoop stress is the tension applied to the iron bands, or hoops, of a wooden barrel. In a straight, closed pipe, any force applied to the cylindrical pipe wall by a pressure differential will ultimately give rise to hoop stresses. Similarly, if this pipe has flat end caps, any force applied to them by static pressure will induce a perpendicular axial stress on the same pipe wall. Thin sections often have negligibly small radial stress, but accurate models of thicker-walled cylindrical shells require such stresses to be considered.
In thick-walled pressure vessels, construction techniques allowing for favorable initial stress patterns can be utilized. These compressive stresses at the inner surface reduce the overall hoop stress in pressurized cylinders. Cylindrical vessels of this nature are generally constructed from concentric cylinders shrunk over (or expanded into) one another, i.e., built-up shrink-fit cylinders, but can also be performed to singular cylinders though autofrettage of thick cylinders.
Definitions
Hoop stress
The hoop stress is the force over area exerted circumferentially (perpendicular to the axis and the radius of the object) in both directions on every particle in the cylinder wall. It can be described as:
where:
F is the force exerted circumferentially on an area of the cylind |
https://en.wikipedia.org/wiki/New%20South%20Wales%20Cancer%20Institute%20Awards | The Cancer Institute NSW Premier's Awards for Outstanding Cancer Research are the premier awards ceremony for the cancer research sector in NSW. Now in its tenth year, the event honours the achievements of the individuals and teams that work across the cancer research sector to lessen the impact of cancer for the people of NSW.
These awards are an opportunity to honour the state's outstanding cancer researchers whose brilliant minds together with their commitment to years and even decades of focused work have led to new discoveries about cancer diagnoses, treatments and survival. Their achievements reflect that improving cancer outcomes is a series of incremental steps.
As the NSW Government's cancer control agency, the Cancer Institute NSW supports, facilitates and collaborates with all in the cancer control sector to translate new discoveries in to meaningful knowledge to improve the health system of NSW. This new information is providing the evidence we need to drive rapid improvement in cancer prevention, treatment, care and ultimately, survival outcomes.
Past award nights
2011 Cancer Research Awards
2012 Cancer Research Awards
2013 Cancer Research Awards
2014 Cancer Research Awards
2015 Cancer Research Awards
2016 NSW Premier's Awards for Outstanding Cancer Research
Outstanding Cancer Researcher of the Year – Professor John Simes
The Professor Rob Sutherland AO Make a Difference Award – Professor Minoti Apte
Outstanding Cancer Research Fellow – Dr Zaklina Kovacevic
The ‘Rising Star’ PhD Student Award – Dr Andrew Chen
Big Data, Big Impact – Associate Professor Daniel Catchpoole and Team, Sydney Children's Hospital Network
Excellence in Translation Cancer Research – Dr Natalie Taylor and Team, Australian Institute of Health Innovation Behaviour Change Research Stream
The ‘Wildfire’ Highly Cited Publication Award – Dr James Wilmott
Innovation in Cancer Clinical Trials – Central Coast Local Health District
2017 NSW Premier's Awar |
https://en.wikipedia.org/wiki/Bernard%20Fr%C3%A9nicle%20de%20Bessy | Bernard Frénicle de Bessy (c. 1604 – 1674), was a French mathematician born in Paris, who wrote numerous mathematical papers, mainly in number theory and combinatorics. He is best remembered for , a treatise on magic squares published posthumously in 1693, in which he described all 880 essentially different normal magic squares of order 4. The Frénicle standard form, a standard representation of magic squares, is named after him. He solved many problems created by Fermat and also discovered the cube property of the number 1729 (Ramanujan number), later referred to as a taxicab number. He is also remembered for his treatise Traité des triangles rectangles en nombres published (posthumously) in 1676 and reprinted in 1729.
Bessy was a member of many of the scientific circles of his day, including the French Academy of Sciences, and corresponded with many prominent mathematicians, such as Mersenne and Pascal. Bessy was also particularly close to Fermat, Descartes and Wallis, and was best known for his insights into number theory.
In 1661 he proposed to John Wallis a problem of what amounted to the following system of equations in integers,
x2 + y2 = z2, x2 = u2 + v2, x − y = u − v > 0.
A solution was given by Théophile Pépin in 1880.
La Méthode des exclusions
Frénicle's La Méthode des exclusions was published (posthumously) in 1693, which appeared in the fifth volume of (1729, Paris), though the work appears to have been written around 1640. The book contains a short introduction followed by ten rules, intended to serve as a "method" or general rules one should apply in order to solve mathematical problems. During the Renaissance, "method" was primarily used for educational purposes, rather than for professional mathematicians (or natural philosophers). However, Frénicle's rules imply slight methodological preferences which suggests a turn towards explorational purposes.
Frénicle's text provided a number of examples on how his rules ought to be applied. He pr |
https://en.wikipedia.org/wiki/History%20of%20superconductivity | Superconductivity is the phenomenon of certain materials exhibiting zero electrical resistance and the expulsion of magnetic fields below a characteristic temperature. The history of superconductivity began with Dutch physicist Heike Kamerlingh Onnes's discovery of superconductivity in mercury in 1911. Since then, many other superconducting materials have been discovered and the theory of superconductivity has been developed. These subjects remain active areas of study in the field of condensed matter physics.
The study of superconductivity has a fascinating history, with several breakthroughs having dramatically accelerated publication and patenting activity in this field, as shown in the figure on the right and described in details below. Throughout its 100+ year history the number of non-patent publications per year about superconductivity has been a factor of 10 larger than the number of patent families, which is characteristic of a technology, that has not achieved a substantial commercial success (see Technological applications of superconductivity).
Exploring ultra-cold phenomena (to 1908)
James Dewar initiated research into electrical resistance at low temperatures. Dewar and John Ambrose Fleming predicted that at absolute zero, pure metals would become perfect electromagnetic conductors (though, later, Dewar altered his opinion on the disappearance of resistance, believing that there would always be some resistance). Walther Hermann Nernst developed the third law of thermodynamics and stated that absolute zero was unattainable. Carl von Linde and William Hampson, both commercial researchers, nearly at the same time filed for patents on the Joule–Thomson effect for the liquefaction of gases. Linde's patent was the climax of 20 years of systematic investigation of established facts, using a regenerative counterflow method. Hampson's designs was also of a regenerative method. The combined process became known as the Hampson–Linde liquefaction process.
Onne |
https://en.wikipedia.org/wiki/Gomphidius%20subroseus | Gomphidius subroseus is a gilled mushroom found in Europe and North America. It was first described by Calvin Henry Kauffman in 1925. It was once thought to be mycorrhizal with Pinus sylvestris. However, Olson et al. (2002) found it to be more likely to be parasitic on Suillus bovinus, which is mycorrhizal with Pinus sylvestris, Pinus sylvestris or both. It is considered edible but of low quality. As with other species of the genus, removing the glutinous cuticle improves the taste.
See also
Gomphidius glutinosus |
https://en.wikipedia.org/wiki/Alternatives%20to%20general%20relativity | Alternatives to general relativity are physical theories that attempt to describe the phenomenon of gravitation in competition with Einstein's theory of general relativity. There have been many different attempts at constructing an ideal theory of gravity.
These attempts can be split into four broad categories based on their scope. In this article, straightforward alternatives to general relativity are discussed, which do not involve quantum mechanics or force unification. Other theories which do attempt to construct a theory using the principles of quantum mechanics are known as theories of quantized gravity. Thirdly, there are theories which attempt to explain gravity and other forces at the same time; these are known as classical unified field theories. Finally, the most ambitious theories attempt to both put gravity in quantum mechanical terms and unify forces; these are called theories of everything.
None of these alternatives to general relativity have gained wide acceptance. General relativity has withstood many tests, remaining consistent with all observations so far. In contrast, many of the early alternatives have been definitively disproven. However, some of the alternative theories of gravity are supported by a minority of physicists, and the topic remains the subject of intense study in theoretical physics.
History of gravitational theory through general relativity
At the time it was published in the 17th century, Isaac Newton's theory of gravity was the most accurate theory of gravity. Since then, a number of alternatives were proposed. The theories which predate the formulation of general relativity in 1915 are discussed in history of gravitational theory.
General relativity
This theory is what we now call "general relativity" (included here for comparison). Discarding the Minkowski metric entirely, Einstein gets:
which can also be written
Five days before Einstein presented the last equation above, Hilbert had submitted a paper containing a |
https://en.wikipedia.org/wiki/Isotopic%20signature | An isotopic signature (also isotopic fingerprint) is a ratio of non-radiogenic 'stable isotopes', stable radiogenic isotopes, or unstable radioactive isotopes of particular elements in an investigated material. The ratios of isotopes in a sample material are measured by isotope-ratio mass spectrometry against an isotopic reference material. This process is called isotope analysis.
Stable isotopes
The atomic mass of different isotopes affect their chemical kinetic behavior, leading to natural isotope separation processes.
Carbon isotopes
For example, different sources and sinks of methane have different affinity for the 12C and 13C isotopes, which allows distinguishing between different sources by the 13C/12C ratio in methane in the air. In geochemistry, paleoclimatology and paleoceanography this ratio is called δ13C. The ratio is calculated with respect to Pee Dee Belemnite (PDB) standard:
‰
Similarly, carbon in inorganic carbonates shows little isotopic fractionation, while carbon in materials originated by photosynthesis is depleted of the heavier isotopes. In addition, there are two types of plants with different biochemical pathways; the C3 carbon fixation, where the isotope separation effect is more pronounced, C4 carbon fixation, where the heavier 13C is less depleted, and Crassulacean Acid Metabolism (CAM) plants, where the effect is similar but less pronounced than with C4 plants. Isotopic fractionation in plants is caused by physical (slower diffusion of 13C in plant tissues due to increased atomic weight) and biochemical (preference of 12C by two enzymes: RuBisCO and phosphoenolpyruvate carboxylase) factors. The different isotope ratios for the two kinds of plants propagate through the food chain, thus it is possible to determine if the principal diet of a human or an animal consists primarily of C3 plants (rice, wheat, soybeans, potatoes) or C4 plants (corn, or corn-fed beef) by isotope analysis of their flesh and bone collagen (however, to obtain |
https://en.wikipedia.org/wiki/Rademacher%E2%80%93Menchov%20theorem | In mathematical analysis, the Rademacher–Menchov theorem, introduced by and , gives a sufficient condition for a series of orthogonal functions on an interval to converge almost everywhere.
Statement
If the coefficients cν of a series of bounded orthogonal functions on an interval satisfy
then the series converges almost everywhere. |
https://en.wikipedia.org/wiki/Representation%20theorem | In mathematics, a representation theorem is a theorem that states that every abstract structure with certain properties is isomorphic to another (abstract or concrete) structure.
Examples
Algebra
Cayley's theorem states that every group is isomorphic to a permutation group.
Representation theory studies properties of abstract groups via their representations as linear transformations of vector spaces.
Stone's representation theorem for Boolean algebras states that every Boolean algebra is isomorphic to a field of sets.
A variant, Stone's representation theorem for distributive lattices, states that every distributive lattice is isomorphic to a sublattice of the power set lattice of some set.
Another variant, Stone's duality, states that there exists a duality (in the sense of an arrow-reversing equivalence) between the categories of Boolean algebras and that of Stone spaces.
The Poincaré–Birkhoff–Witt theorem states that every Lie algebra embeds into the commutator Lie algebra of its universal enveloping algebra.
Ado's theorem states that every finite-dimensional Lie algebra over a field of characteristic zero embeds into the Lie algebra of endomorphisms of some finite-dimensional vector space.
Birkhoff's HSP theorem states that every model of an algebra A is the homomorphic image of a subalgebra of a direct product of copies of A.
In the study of semigroups, the Wagner–Preston theorem provides a representation of an inverse semigroup S, as a homomorphic image of the set of partial bijections on S, and the semigroup operation given by composition.
Category theory
The Yoneda lemma provides a full and faithful limit-preserving embedding of any category into a category of presheaves.
Mitchell's embedding theorem for abelian categories realises every small abelian category as a full (and exactly embedded) subcategory of a category of modules over some ring.
Mostowski's collapsing theorem states that every well-founded extensional structure is isomorphic t |
https://en.wikipedia.org/wiki/Pinocytosis | In cellular biology, pinocytosis, otherwise known as fluid endocytosis and bulk-phase pinocytosis, is a mode of endocytosis in which small molecules dissolved in extracellular fluid are brought into the cell through an invagination of the cell membrane, resulting in their containment within a small vesicle inside the cell. These pinocytotic vesicles then typically fuse with early endosomes to hydrolyze (break down) the particles.
Pinocytosis is variably subdivided into categories depending on the molecular mechanism and the fate of the internalized molecules.
Function
In humans, this process occurs primarily for absorption of fat droplets. In endocytosis the cell plasma membrane extends and folds around desired extracellular material, forming a pouch that pinches off creating an internalized vesicle. The invaginated pinocytosis vesicles are much smaller than those generated by phagocytosis. The vesicles eventually fuse with the lysosome, whereupon the vesicle contents are digested. Pinocytosis involves a considerable investment of cellular energy in the form of ATP.
Pinocytosis and ATP
Pinocytosis is used primarily for clearing extracellular fluids (ECF) and as part of immune surveillance. In contrast to phagocytosis, it generates very small amounts of ATP from the wastes of alternative substances such as lipids (fat). Unlike receptor-mediated endocytosis, pinocytosis is nonspecific in the substances that it transport: the cell takes in surrounding fluids, including all solutes present.
Etymology and pronunciation
The word pinocytosis () uses combining forms of pino- + cyto- + -osis, all Neo-Latin from Greek, reflecting píno, to drink, and cytosis. The term was proposed by W. H. Lewis in 1931.
Non-specific, adsorptive pinocytosis
Non-specific, adsorptive pinocytosis is a form of endocytosis, a process in which small particles are taken in by a cell by splitting off small vesicles from the cell membrane. Cationic proteins bind to the negative cell surface and |
https://en.wikipedia.org/wiki/CRTC3 | CREB-regulated transcription coactivator 3 is a protein that in humans is encoded by the CRTC3 gene.
This gene has been shown to be linked to weight gain. |
https://en.wikipedia.org/wiki/Climate%20Clock | The Climate Clock is a graphic to demonstrate how quickly the planet is approaching 1.5 °C of global warming, given current emissions trends. It also shows the amount of CO2 already emitted, and the global warming to date.
The Climate Clock was launched in 2015 to provide a measuring stick against which viewers can track climate change mitigation progress. The date shown when humanity reaches 1.5°C will move closer as emissions rise, and further away as emissions decrease. An alternative view projects the time remaining to 2.0°C of warming. The clock is updated every year to reflect the latest global CO2 emissions trend and rate of climate warming. As of June 2022, the clock counts down towards late July 2029. On September 20, 2021, the clock was delayed to July 28, 2028, likely because of the COP26 Conference and the land protection by indigenous peoples.
The clock is hosted by Human Impact Lab, itself part of Concordia University. Organisations supporting the climate clock include Concordia University, the David Suzuki Foundation, Future Earth, and the Climate Reality Project.
Relevance
1.5 °C is an important threshold for many climate impacts, as shown by the Special Report on Global Warming of 1.5 °C. Every increment to global temperature is expected to increase weather extremes, such as heat waves and extreme precipitation events. There is also the risk of irreversible ice sheet loss. Consequent sea level rise also increases sharply between 1.5 °C and 2 °C, and virtually all corals could be wiped out at 2 °C warming.
The New York Climate Clock
In late September 2020, artists and activists, Gan Golan, Katie Peyton Hofstadter, Adrian Carpenter and Andrew Boyd repurposed the Metronome in Union Square in New York City to show the Climate Clock. The goal was to "remind the world every day just how perilously close we are to the brink." This is in juxtaposition to the Doomsday Clock, which measures a variety of factors that could lead to "destroying the world" u |
https://en.wikipedia.org/wiki/Type%20generalization | Type generalization is a technique commonly used in refactoring. The idea is to draw on the benefits of object-orientation and make more-generalized types, thus enabling more code sharing, leading to better maintainability as there is less code to write. Too-general code can, however, become completely useless, leading to spaghetti code doing effectively nothing.
Type generalization refers to making more general or more abstract some subset of the traits of a specific type. A superclass has wider use than a specific subclass, and so is more 'general'.
An example of generalizing a type would be moving a method from a child to a parent class for common use by all the parent class' children, not just the original child.
Another example, in the Java programming language, would be access to an object via an interface which isn't tied into a specific implementation of that interface. |
https://en.wikipedia.org/wiki/Term%20logic | In logic and formal semantics, term logic, also known as traditional logic, syllogistic logic or Aristotelian logic, is a loose name for an approach to formal logic that began with Aristotle and was developed further in ancient history mostly by his followers, the Peripatetics. It was revived after the third century CE by Porphyry's Isagoge.
Term logic revived in medieval times, first in Islamic logic by Alpharabius in the tenth century, and later in Christian Europe in the twelfth century with the advent of new logic, remaining dominant until the advent of predicate logic in the late nineteenth century.
However, even if eclipsed by newer logical systems, term logic still plays a significant role in the study of logic. Rather than radically breaking with term logic, modern logics typically expand it.
Aristotle's system
Aristotle's logical work is collected in the six texts that are collectively known as the Organon. Two of these texts in particular, namely the Prior Analytics and De Interpretatione, contain the heart of Aristotle's treatment of judgements and formal inference, and it is principally this part of Aristotle's works that is about term logic. Modern work on Aristotle's logic builds on the tradition started in 1951 with the establishment by Jan Lukasiewicz of a revolutionary paradigm. Lukasiewicz's approach was reinvigorated in the early 1970s by John Corcoran and Timothy Smiley – which informs modern translations of Prior Analytics by Robin Smith in 1989 and Gisela Striker in 2009.
The Prior Analytics represents the first formal study of logic, where logic is understood as the study of arguments. An argument is a series of true or false statements which lead to a true or false conclusion. In the Prior Analytics, Aristotle identifies valid and invalid forms of arguments called syllogisms. A syllogism is an argument that consists of at least three sentences: at least two premises and a conclusion. Although Aristotle does not call them "categorical |
https://en.wikipedia.org/wiki/Cleanroom | A cleanroom or clean room is an engineered space, which maintains a very low concentration of airborne particulates. It is well isolated, well-controlled from contamination, and actively cleansed. Such rooms are commonly needed for scientific research, and in industrial production for all nanoscale processes, such as semiconductor manufacturing. A cleanroom is designed to keep everything from dust, to airborne organisms, or vaporised particles, away from it, and so from whatever material is being handled inside it.
A cleanroom can also prevent the escape of materials. This is often the primary aim in hazardous biology and nuclear work, in pharmaceutics and in virology.
Cleanrooms typically come with a cleanliness level quantified by the number of particles per cubic meter at a predetermined molecule measure. The ambient outdoor air in a typical urban area contains 35,000,000 particles for each cubic meter in the size range 0.5 μm and bigger, equivalent to an ISO 9 certified cleanroom. By comparison an ISO 14644-1 level 1 certified cleanroom permits no particles in that size range, and just 12 particles for each cubic meter of 0.3 μm and smaller. Semiconductor facilities often get by with level 7 or 5, while level 1 facilities are exceedingly rare.
History
The modern cleanroom was invented by American physicist Willis Whitfield. As employee of the Sandia National Laboratories, Whitfield created the initial plans for the cleanroom in 1960. Prior to Whitfield's invention, earlier cleanrooms often had problems with particles and unpredictable airflows. Whitfield designed his cleanroom with a constant, highly filtered air flow to flush out impurities. Within a few years of its invention in the 1960s, Whitfield's modern cleanroom had generated more than US$50 billion in sales worldwide (approximately $ billion today).
The majority of the integrated circuit manufacturing facilities in Silicon Valley were made by three companies: MicroAire, PureAire, and Key Plastics. T |
https://en.wikipedia.org/wiki/NDE1 | Nuclear distribution protein nudE homolog 1 is a protein that in humans is encoded by the NDE1 gene.
Clinical significance
Mutations in both copies of NDE1 cause microlissencephaly type 4. |
https://en.wikipedia.org/wiki/Water%20power%20engine | A water power engine includes prime movers driven by water and which may be classified under three categories:
Water pressure motors, having a piston and cylinder with inlet and outlet valves: their action is that analogous of a steam- or gas-engine with water as the working fluid – see water engine
Water wheels
Turbines, deriving their energy from high velocity jet of jets (the impulse machine), or from water supplied under pressure and passing through the vanes of a runner which is thereby caused to rotate (the reaction type)
Hydro power is generated when the natural force from the water's current moves a device (fan, propeller, wheel) that is pushed by the force of the water. Ordinary water weighs 8.36 lbs per gallon (1 kg per liter). The force make the turbine mechanism spin, creating electricity. As long as there is flow, it is possible to produce electricity. The advantage of electricity generated in this way is that it is a renewable resource. A small-scale Micro Hydro Power can be a reliable and long lasting piece of technology. The disadvantage of the system is that technology has yet to be developed more than what it is today.
Stanley Myer
As the prices for gasoline continued to soar a man of many inventions named Stanley Myer worked on a solution that would cut the cost of fueling our cars as well as help the planet. The war on the supply and demand of a necessity for vehicles would become a distant memory if Myer could make his invention work for all vehicles. Myer transformed a dune buggy's fuel system into a system that used water to fuel its engine, which replaced gasoline. The idea was to have cars altered to accommodate the water powered engines. On June 24, 1992 Myer applied to have his work patented. He was a man of many inventions and patents such as his work on Process and apparatus for the production of fuel gas and the enhanced release of thermal energy from such gas, Method for the production of a fuel gas, Controlled process for the |
https://en.wikipedia.org/wiki/Cam%20plastometer | The cam plastometer is a physical testing machine. It measures the resistance of non-brittle materials to compressive deformation at constant true-strain rates. In this way, it can be compared a bit to the Gleeble®. In the early days, the machine operates at relatively low strain rates, but over time it has been enhanced and currently it can operate over a wide range of strain rates
The machine is patented under the name of "United States Patent 4109516".
In the machine, deformation compressive forces are applied to a specimen by two flat, opposing platens which impact a flat, rectangular specimen. The deformation forces can be varied during operation, to simulate actual conditions which occur during industrial pressing and forming operations. The plastometer is also capable of torsional testing of specimens".
The cam plastometers are expensive and there are only a few of them in the world. |
https://en.wikipedia.org/wiki/Passenger%20name%20record | A passenger name record (PNR) is a record in the database of a computer reservation system (CRS) that contains the itinerary for a passenger or a group of passengers travelling together. The concept of a PNR was first introduced by airlines that needed to exchange reservation information in case passengers required flights of multiple airlines to reach their destination ("interlining"). For this purpose, IATA and ATA have defined standards for interline messaging of PNR and other data through the "ATA/IATA Reservations Interline Message Procedures - Passenger" (AIRIMP). There is no general industry standard for the layout and content of a PNR. In practice, each CRS or hosting system has its own proprietary standards, although common industry needs, including the need to map PNR data easily to AIRIMP messages, has resulted in many general similarities in data content and format between all of the major systems.
When a passenger books an itinerary, the travel agent or travel website user will create a PNR in the computer reservation system it uses. This is typically one of the large global distribution systems, such as Amadeus, Sabre, or Travelport (Apollo, Galileo, and Worldspan) but if the booking is made directly with an airline the PNR can also be in the database of the airline's CRS. This PNR is called the Master PNR for the passenger and the associated itinerary. The PNR is identified in the particular database by a record locator.
When portions of the travel are not provided by the holder of the master PNR, then copies of the PNR information are sent to the CRSs of the airlines that will be providing transportation. These CRSs will open copies of the original PNR in their own database to manage the portion of the itinerary for which they are responsible. Many airlines have their CRS hosted by one of the GDSs, which allows sharing of the PNR.
The record locators of the copied PNRs are communicated back to the CRS that owns the Master PNR, so all records remai |
https://en.wikipedia.org/wiki/Normal%20cone | In algebraic geometry, the normal cone of a subscheme of a scheme is a scheme analogous to the normal bundle or tubular neighborhood in differential geometry.
Definition
The normal cone or of an embedding , defined by some sheaf of ideals I is defined as the relative Spec
When the embedding i is regular the normal cone is the normal bundle, the vector bundle on X corresponding to the dual of the sheaf .
If X is a point, then the normal cone and the normal bundle to it are also called the tangent cone and the tangent space (Zariski tangent space) to the point. When Y = Spec R is affine, the definition means that the normal cone to X = Spec R/I is the Spec of the associated graded ring of R with respect to I.
If Y is the product X × X and the embedding i is the diagonal embedding, then the normal bundle to X in Y is the tangent bundle to X.
The normal cone (or rather its projective cousin) appears as a result of blow-up. Precisely, let
be the blow-up of Y along X. Then, by definition, the exceptional divisor is the pre-image ; which is the projective cone of . Thus,
The global sections of the normal bundle classify embedded infinitesimal deformations of Y in X; there is a natural bijection between the set of closed subschemes of , flat over the ring D of dual numbers and having X as the special fiber, and H0(X, NX Y).
Properties
Compositions of regular embeddings
If are regular embeddings, then is a regular embedding and there is a natural exact sequence of vector bundles on X:
If are regular embeddings of codimensions and if is a regular embedding of codimension then
In particular, if is a smooth morphism, then the normal bundle to the diagonal embedding (r-fold) is the direct sum of copies of the relative tangent bundle .
If is a closed immersion and if is a flat morphism such that , then
If is a smooth morphism and is a regular embedding, then there is a natural exact sequence of vector bundles on X:
(which is a special case of an exa |
https://en.wikipedia.org/wiki/Ramanujan%20tau%20function | The Ramanujan tau function, studied by , is the function defined by the following identity:
where with , is the Euler function, is the Dedekind eta function, and the function is a holomorphic cusp form of weight 12 and level 1, known as the discriminant modular form (some authors, notably Apostol, write instead of ). It appears in connection to an "error term" involved in counting the number of ways of expressing an integer as a sum of 24 squares. A formula due to Ian G. Macdonald was given in .
Values
The first few values of the tau function are given in the following table :
Ramanujan's conjectures
observed, but did not prove, the following three properties of :
if (meaning that is a multiplicative function)
for prime and .
for all primes .
The first two properties were proved by and the third one, called the Ramanujan conjecture, was proved by Deligne in 1974 as a consequence of his proof of the Weil conjectures (specifically, he deduced it by applying them to a Kuga-Sato variety).
Congruences for the tau function
For and , define as the sum of the th powers of the divisors of . The tau function satisfies several congruence relations; many of them can be expressed in terms of . Here are some:
For prime, we have
<li>
<li>
<li>
Explicit formula
In 1975 Douglas Niebur proved an explicit formula for the Ramanujan tau function:
Conjectures on τ(n)
Suppose that is a weight- integer newform and the Fourier coefficients are integers. Consider the problem:
Given that does not have complex multiplication, do almost all primes have the property that ?
Indeed, most primes should have this property, and hence they are called ordinary. Despite the big advances by Deligne and Serre on Galois representations, which determine for coprime to , it is unclear how to compute . The only theorem in this regard is Elkies' famous result for modular elliptic curves, which guarantees that there are infinitely many primes such that , which thus are con |
https://en.wikipedia.org/wiki/Magnetobiology | Magnetobiology is the study of biological effects of mainly weak static and low-frequency magnetic fields, which do not cause heating of tissues. Magnetobiological effects have unique features that obviously distinguish them from thermal effects; often they are observed for alternating magnetic fields just in separate frequency and amplitude intervals. Also, they are dependent of simultaneously present static magnetic or electric fields and their polarization.
Magnetobiology is a subset of bioelectromagnetics. Bioelectromagnetism and biomagnetism are the study of the production of electromagnetic and magnetic fields by biological organisms. The sensing of magnetic fields by organisms is known as magnetoreception.
Biological effects of weak low frequency magnetic fields, less than about 0.1 millitesla (or 1 Gauss) and 100 Hz correspondingly, constitutes a physics problem. The effects look paradoxical, for the energy quantum of these electromagnetic fields is by many orders of value less than the energy scale of an elementary chemical act. On the other hand, the field intensity is not enough to cause any appreciable heating of biological tissues or irritate nerves by the induced electric currents.
Effects
An example of a magnetobiological effect is the magnetic navigation by migrant animals by means of magnetoreception.
Many animal orders, such as certain birds, marine turtles, reptiles, amphibians and salmonoid fishes are able to detect small variations of the geomagnetic field and its magnetic inclination to find their seasonal habitats. They are said to use an "inclination compass". Certain crustaceans, spiny lobsters, bony fish, insects and mammals have been found to use a "polarity compass", whereas in snails and cartilageous fish the type of compass is as yet unknown. Little is known about other vertebrates and arthropods. Their perception can be on the order of tens of nanoteslas.
Magnetic intensity as a component of the navigational ‘map’ of pigeons |
https://en.wikipedia.org/wiki/Steganography%20tools | A steganography software tool allows a user to embed hidden data inside a carrier file, such as an image or video, and later extract that data.
It is not necessary to conceal the message in the original file at all. Thus, it is not necessary to modify the original file and thus, it is difficult to detect anything. If a given section is subjected to successive bitwise manipulation to generate the cyphertext, then there is no evidence in the original file to show that it is being used to encrypt a file.
Architecture
Carrier
The carrier is the signal, stream, or data file into which the hidden data is hidden by making subtle modifications. Examples include audio files, image files, documents, and executable files. In practice, the carrier should look and work the same as the original unmodified carrier, and should appear benign to anyone inspecting it.
Certain properties can raise suspicion that a file is carrying hidden data:
If the hidden data is large relative to the carrier content, as in an empty document that is a megabyte in size.
The use of obsolete formats or poorly-supported extensions which break commonly used tools.
It is a cryptographic requirement that the carrier (e.g. photo) is original, not a copy of something publicly available (e.g., downloaded). This is because the publicly available source data could be compared against the version with a hidden message embedded.
There is a weaker requirement that the embedded message not change the carrier's statistics (or other metrics) such that the presence of a message is detectable. For instance, if the least-significant-bits of the red camera-pixel channel of an image has a Gaussian distribution given a constant colored field, simple image steganography which produces a random distribution of these bits could allow discrimination of stego images from unchanged ones.
The sheer volume of modern (ca 2014) and inane high-bandwidth media (e.g., youtube.com, bittorrent sources. eBay, Facebook, spam, etc. |
https://en.wikipedia.org/wiki/ECRYPT | ECRYPT (European Network of Excellence in Cryptology) was a 4-year European research initiative launched on 1 February 2004 with the stated objective of promoting the collaboration of European researchers in information security, and especially in cryptology and digital watermarking.
ECRYPT listed five core research areas, termed "virtual laboratories": symmetric key algorithms (STVL), public key algorithms (AZTEC), protocol (PROVILAB), secure and efficient implementations (VAMPIRE) and watermarking (WAVILA).
In August 2008 the network started another 4-year phase as ECRYPT II.
ECRYPT II products
Yearly report on algorithms and key lengths
During the project, algorithms and key lengths were evaluated yearly. The most recent of these documents is dated 30 September 2012.
Key sizes
Considering the budget of a large intelligence agency to be about US$300 million for a single ASIC machine, the recommended minimum key size is 84 bits, which would give protection for a few months. In practice, most commonly used algorithms have key sizes of 128 bits or more, providing sufficient security also in the case that the chosen algorithm is slightly weakened by cryptanalysis.
Different kinds of keys are compared in the document (e.g. RSA keys vs. EC keys). This "translation table" can be used to roughly equate keys of other types of algorithms with symmetric encryption algorithms. In short, 128 bit symmetric keys are said to be equivalent to 3248 bits RSA keys or 256-bit EC keys. Symmetric keys of 256 bits are roughly equivalent to 15424 bit RSA keys or 512 bit EC keys. Finally 2048 bit RSA keys are said to be equivalent to 103 bit symmetric keys.
Among key sizes, 8 security levels are defined, from the lowest "Attacks possible in real-time by individuals" (level 1, 32 bits) to "Good for the foreseeable future, also against quantum computers unless Shor's algorithm applies" (level 8, 256 bits). For general long-term protection (30 years), 128 bit keys are recommended ( |
https://en.wikipedia.org/wiki/SpankChain | SpankChain is an adult entertainment website and cryptocurrency exchange mostly used for exchanges in the sex work industry. Users pay for services using SpankChain Ethereum-based coin "SPANK". The SpankChain's tokens are sometimes referred to as "SpankCoin".
History
In April 2018, SpankChain offered a $25,000 reward to sex workers who revealed information about political clients who supported the passing of the FOSTA/SESTA acts, which regulated sex work in the United States. The company reportedly had 6,000 users as of October 2018.
In 2018, a malicious attacker stole 165 Ethers (valued at $40,000) from SpankChain by exploiting a vulnerability in the Ethereum blockchain. After the cryptocurrency bubble of 2018 burst, the company downsized to eight employees. |
https://en.wikipedia.org/wiki/Enterprise%20value | Enterprise value (EV), total enterprise value (TEV), or firm value (FV) is an economic measure reflecting the market value of a business (i.e. as distinct from market price). It is a sum of claims by all claimants: creditors (secured and unsecured) and shareholders (preferred and common). Enterprise value is one of the fundamental metrics used in business valuation, financial analysis, accounting, portfolio analysis, and risk analysis.
Enterprise value is more comprehensive than market capitalization, which only reflects common equity. Importantly, EV reflects the opportunistic nature of business and may change substantially over time because of both external and internal conditions. Therefore, financial analysts often use a comfortable range of EV in their calculations.
EV equation
For detailed information on the valuation process see Valuation (finance).
Enterprise value =
common equity at market value (this line item is also known as "market cap")
+ debt at market value (here debt refers to interest-bearing liabilities, both long-term and short-term)
+ preferred equity at market value
+ unfunded pension liabilities and other debt-deemed provisions
– value of associate companies
– cash and cash equivalents.
Understanding
A simplified way to understand the EV concept is to envision purchasing an entire business. If you settle with all the security holders, you pay EV. Counterintuitively, increases or decreases in enterprise value do not necessarily correspond to "value creation" or "value destruction". Any acquisition of assets (whether paid for in cash or through share issues) will increase EV, whether or not those assets are productive. Similarly, reductions in capital intensity (for example by reducing working capital) will reduce EV.
EV can be negative if the company, for example, holds abnormally high amounts of cash that are not reflected in the market value of the stock and total capitalization.
All the components are relevant in liquidation a |
https://en.wikipedia.org/wiki/Astragalus%20coarctatus | Astragalus coarctatus is a species of milkvetch that is endemic to northeastern Turkey, and is only known from its type specimen, collected in 1871 in Kars Province. |
https://en.wikipedia.org/wiki/Carvone | Carvone is a member of a family of chemicals called terpenoids. Carvone is found naturally in many essential oils, but is most abundant in the oils from seeds of caraway (Carum carvi), spearmint (Mentha spicata), and dill.
Uses
Both carvones are used in the food and flavor industry. R-(−)-Carvone is also used for air freshening products and, like many essential oils, oils containing carvones are used in aromatherapy and alternative medicine. S-(+)-Carvone has shown a suppressant effect against high-fat diet induced weight gain in mice.
Food applications
As the compound most responsible for the flavor of caraway, dill and spearmint, carvone has been used for millennia in food. Wrigley's Spearmint Gum and spearmint flavored Life Savers are major users of natural spearmint oil from Mentha spicata. Caraway seed is extracted with alcohol to make the European drink Kümmel.
Agriculture
S-(+)-Carvone is also used to prevent premature sprouting of potatoes during storage, being marketed in the Netherlands for this purpose under the name Talent.
Insect control
R-(−)-Carvone has been approved by the U.S. Environmental Protection Agency for use as a mosquito repellent.
Organic synthesis
Carvone is available inexpensively in both enantiomerically pure forms, making it an attractive starting material for the asymmetric total synthesis of natural products. For example, (S)-(+)-carvone was used to begin a 1998 synthesis of the terpenoid quassin:<ref>(a) Shing, T. K. M.; Jiang, Q; Mak, T. C. W. J. Org. Chem. 1998, 63, 2056-2057. (b) Shing, T. K. M.; Tang, Y. J. Chem. Soc. Perkin Trans. 1 1994, 1625.</ref>
Stereoisomerism and odor
Carvone forms two mirror image forms or enantiomers: R-(−)-carvone, has a sweetish minty smell, like spearmint leaves. Its mirror image, S-(+)-carvone, has a spicy aroma with notes of rye, like caraway seeds. The fact that the two enantiomers are perceived as smelling different is evidence that olfactory receptors must respond more strongly to on |
https://en.wikipedia.org/wiki/Unnatural%20Selection%20%28video%20game%29 | Unnatural Selection is a 1993 game for DOS by Maxis.
Gameplay
In the game, the player breeds mutant animals to fight battles. The game has two phases, the first is the breeding phase in which the player uses various objects and methods (food, drugs, radiation) etc. to breed the animals which will fight future battles. The second is the battle phase in which the animals are deployed on the battlefield in order to combat those of a rogue scientist.
Reception
A 1994 Computer Gaming World survey of strategic space games set in the year 2000 and later gave the game three-plus stars out of five, stating that it was "A different concept, almost carried off with success". |
https://en.wikipedia.org/wiki/The%20Business%20Cloud | The Business Cloud is an API enabled self-service platform, developed by Domo, that provides an array of services like data connection and data visualization.
History
Domo, Inc. was founded in 2010 by Josh James who also co-founded the web analytics software company Omniture in 1996, which he took public in 2006.
Domo launched the Domo Appstore, with a 1000 apps with social and mobile capabilities, in 2016. This appstore creates a network of business apps and an ecosystem of companies into a single, integrated business cloud. This decision came after Domo announced a $131 million round of funding from BlackRock.
According to the company, the concept behind The Business Cloud is to connect smaller clouds relating to apps or other functional areas of a business into a single business cloud that allows self-service and other social features to customers.
Services
The Business Cloud is offered as a free service, claimed to be the world's first business cloud with Domo appstore as one of its core services. This free package includes all of the Domo's features and functionality including Domo platform, Domo Apps, visualizations, alerts, company directories, org charts, profiles, tasks and Domo Mobile. The Business Cloud allows customers to leverage their preferred cloud as well as on-premises software and monitor all aspects of their business in routine.
The company is supported by a $500 million fund from investors all over the world. |
https://en.wikipedia.org/wiki/Biological%20specificity | Biological specificity is the tendency of a characteristic such as a behavior or a biochemical variation to occur in a particular species.
Biochemist Linus Pauling stated that "Biological specificity is the set of characteristics of living organisms or constituents of living organisms of being special or doing something special. Each animal or plant species is special. It differs in some way from all other species...biological specificity is the major problem about understanding life."
Biological specificity within Homo sapiens
Homo sapiens has many characteristics that show the biological specificity in the form of behavior and morphological traits.
Morphologically, humans have an enlarged cranial capacity and more gracile features in comparison to other hominins. The reduction of dentition is a feature that allows for the advantage of adaptability in diet and survival. As a species, humans are culture dependent and much of human survival relies on the culture and social relationships. With the evolutionary change of the reduction of the pelvis and enlarged cranial capacity; events like childbirth are dependent on a safe, social setting to assist in the childbirth; a birthing mother will seek others when going into labor. This is a uniquely human experience, as other animals are able to give birth on their own and often choose to isolate themselves to do so to protect their young.
An example of a genetic adaptation unique to humans is the gene apolipoprotein E (APOE4) on chromosome 19. While chimpanzees may have the APOE gene, the study "The apolipoprotein E (APOE) gene appears functionally monomorphic in chimpanzees" shows that the diversity of the APOE gene in humans in unique. The polymorphism in APOE is only in humans as they carry alleles APOE2, APOE3, APOE4; APOE4 which allows human to break down fatty protein and eat more protein than their ancestors is also a genomic risk factor for Alzheimer's disease.
There are many behavioral characteristics that a |
https://en.wikipedia.org/wiki/Levantine%20corridor | The Levantine corridor is the relatively narrow strip between the Mediterranean Sea to the northwest and deserts to the southeast, which connects Africa to Eurasia. This corridor is a land route of migrations of animals between Eurasia and Africa. In particular, it is believed that early hominins spread from Africa to Eurasia via the Levantine corridor and Horn of Africa. The corridor is named after the Levant.
Location and geography
The Levantine Corridor is the western part of the Fertile Crescent, the eastern part being Mesopotamia.
Dispersal route for plants
Botanists recognize this area as a dispersal route of plant species.
Dispersal route for humans
The distribution of Y-chromosome and mtDNA haplogroups suggests that during the Paleolithic and Mesolithic periods, the Levantine corridor was more important for bi-directional human migrations between Africa and Eurasia than was the Horn of Africa.
The term is used frequently by archaeologists as an area that includes Cyprus, where important developments occurred during the Neolithic revolution.
The first sedentary villages were established around fresh water springs and lakes in the Levantine corridor by the Natufian culture. |
https://en.wikipedia.org/wiki/Claudia%20Mitchell | Claudia Mitchell (born 1980) is a former US Marine whose left arm was amputated near the shoulder following a motorcycle crash in 2004. She became the first woman to be outfitted with a bionic arm. The arm is controlled through muscles in her chest and side, which in turn are controlled by the nerves that had previously controlled her real arm. The nerves were rerouted to these muscles in a process of targeted reinnervation.
Her prosthesis, a prototype developed by the Rehabilitation Institute of Chicago was one of the most advanced prosthetic arms developed to date. |
https://en.wikipedia.org/wiki/Glycoside%20hydrolase | In biochemistry, glycoside hydrolases (also called glycosidases or glycosyl hydrolases) are a class of enzymes which catalyze the hydrolysis of glycosidic bonds in complex sugars. They are extremely common enzymes, with roles in nature including degradation of biomass such as cellulose (cellulase), hemicellulose, and starch (amylase), in anti-bacterial defense strategies (e.g., lysozyme), in pathogenesis mechanisms (e.g., viral neuraminidases) and in normal cellular function (e.g., trimming mannosidases involved in N-linked glycoprotein biosynthesis). Together with glycosyltransferases, glycosidases form the major catalytic machinery for the synthesis and breakage of glycosidic bonds.
Occurrence and importance
Glycoside hydrolases are found in essentially all domains of life. In prokaryotes, they are found both as intracellular and extracellular enzymes that are largely involved in nutrient acquisition. One of the important occurrences of glycoside hydrolases in bacteria is the enzyme beta-galactosidase (LacZ), which is involved in regulation of expression of the lac operon in E. coli. In higher organisms glycoside hydrolases are found within the endoplasmic reticulum and Golgi apparatus where they are involved in processing of N-linked glycoproteins, and in the lysosome as enzymes involved in the degradation of carbohydrate structures. Deficiency in specific lysosomal glycoside hydrolases can lead to a range of lysosomal storage disorders that result in developmental problems or death. Glycoside hydrolases are found in the intestinal tract and in saliva where they degrade complex carbohydrates such as lactose, starch, sucrose and trehalose. In the gut they are found as glycosylphosphatidyl anchored enzymes on endothelial cells. The enzyme lactase is required for degradation of the milk sugar lactose and is present at high levels in infants, but in most populations will decrease after weaning or during infancy, potentially leading to lactose intolerance in adul |
https://en.wikipedia.org/wiki/Adrenal%20androgen-stimulating%20hormone | Adrenal androgen stimulating hormone (AASH), also known as cortical androgen stimulating hormone (CASH), is a hypothetical hormone which has been proposed to stimulate the adrenal glands to produce adrenal androgens such as dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and androstenedione (A4). It is hypothesized to be involved in adrenarche and adrenopause. The existence of this hormone is controversial and disputed and it has not been identified to date. A number of other mechanisms and/or hormones may instead play the functional role of the so-called AASH.
See also
Adrenocorticotrophic hormone (ACTH) |
https://en.wikipedia.org/wiki/Isle%20of%20Wight%20Garlic%20Festival | The Isle of Wight Garlic Festival is a fundraising event that is held annually on the Isle of Wight to support the island's garlic industry, as well as fundraising for other agricultural farms on the island.
History
The Garlic Festival has been held every year since 1983, except 2020-21 when officials cited the COVID-19 pandemic that caused its cancellation. 2022 saw its resumption. From 1985 to 2006, the Newchurch Parish Sports & Community Association organised the annual Garlic Festival, achieving their major fundraising goals. It has recently drawn 20,000 visitors a year.
Further entertainment has included live music from artists such as The Wurzels, Chas & Dave, Alvin Stardust, the Glitter Band, Chesney Hawkes, Kiki Dee, and Jim Diamond.
See also
Gilroy Garlic Festival |
https://en.wikipedia.org/wiki/Protocol%20converter | A protocol converter is a device used to convert standard or proprietary protocol of one device to the protocol suitable for the other device or tools to achieve the desired interoperability. Protocols are software installed on the routers, which convert the data formats, data rate and protocols of one network into the protocols of the network in which data is navigating. There are varieties of protocols used in different fields like power generation, transmission and distribution, oil and gas, automation, utilities, and remote monitoring applications. The major protocol translation messages involve conversion of data messages, events, commands, and time synchronization.
General architecture
The general architecture of a protocol converter includes an internal master protocol communicating to the external slave devices and the data collected is used to update the internal database of the converter. When the external master requests for data, the internal slave collects data from the database and send it to the external master. There will be different schemes for handling the spontaneous reporting of events and commands. There can be different physical medium for communication on protocol-X & Y, which include RS-232, RS-485, Ethernet, etc.
Applications of protocol converters
Protocol Converter applications vary from industry to industry. The protocol converter can be a software converter, hardware converter, or an integrated converter depending on the protocols.
Some of the key applications are:
Substation automation
Building automation
Process automation
The major protocols used in each area of application are listed under List of automation protocols.
Latency and engineering issues in using protocol converters
Protocol Converters are generally used for transforming data and commands from one device or application to another. This necessarily involves transformation of data, commands, their representation, encoding and framing to achieve the conversion. |
https://en.wikipedia.org/wiki/UCT%20Mathematics%20Competition | The UCT Mathematics Competition is an annual mathematics competition for schools in the Western Cape province of South Africa, held at the University of Cape Town.
Around 7000 participants from Grade 8 to Grade 12 take part, writing a multiple-choice paper. Individual and pair entries are accepted, but all write the same paper for their grade.
The current holder of the School Trophy is Rondebosch Boys High School, with Diocesan College achieving second place in the 2022 competition. These two schools have held the top positions in the competition for a number of years.
The competition was established in 1977 by Mona Leeuwenberg and Shirley Fitton, who were teachers at Diocesan College and Westerford High School, and since 1987 has been run by Professor John Webb of the University of Cape Town.
Awards
Mona Leeuwenburg Trophy
The Mona Leeuwenburg Trophy is awarded to the school with the best overall performance in the competition.
UCT Trophy
The UCT Trophy is awarded to the school with the best performance that has not participated in the competition more than twice before.
Diane Tucker Trophy
The Diane Tucker Trophy is awarded to the girl with the best performance in the competition. This trophy was first made in year 2000.
Moolla Trophy
The Moolla Trophy was donated to the competition by the Moolla family. Saadiq, Haroon and Ashraf Moolla represented Rondebosch Boys' High School and achieved Gold Awards from 2003 to 2011. The trophy is awarded to a school from a disadvantaged community that shows a notable performance in the competition.
Lesley Reeler Trophy
The Lesley Reeler Trophy is awarded for the best individual performance over five years (grades 8 to 12). |
https://en.wikipedia.org/wiki/Calcium%20imaging | Calcium imaging is a microscopy technique to optically measure the calcium (Ca2+) status of an isolated cell, tissue or medium. Calcium imaging takes advantage of calcium indicators, fluorescent molecules that respond to the binding of Ca2+ ions by fluorescence properties. Two main classes of calcium indicators exist: chemical indicators and genetically encoded calcium indicators (GECI). This technique has allowed studies of calcium signalling in a wide variety of cell types. In neurons, electrical activity is always accompanied by an influx of Ca2+ ions. Thus, calcium imaging can be used to monitor the electrical activity in hundreds of neurons in cell culture or in living animals, which has made it possible to dissect the function of neuronal circuits.
Chemical indicators
Chemical indicators are small molecules that can chelate calcium ions. All these molecules are based on an EGTA homologue called BAPTA, with high selectivity for calcium (Ca2+) ions versus magnesium (Mg2+) ions.
This group of indicators includes fura-2, indo-1, fluo-3, fluo-4, Calcium Green-1.
These dyes are often used with the chelator carboxyl groups masked as acetoxymethyl esters, in order to render the molecule lipophilic and to allow easy entrance into the cell. Once this form of the indicator is in the cell, cellular esterases will free the carboxyl groups and the indicator will be able to bind calcium. The free acid form of the dyes (i.e. without the acetoxymethyl ester modification) can also be directly injected into cells via a microelectrode or micropipette which removes uncertainties as to the cellular compartment holding the dye (the acetoxymethyl ester can also enter the endoplasmic reticulum and mitochondria). Binding of a Ca2+ ion to a fluorescent indicator molecule leads to either an increase in quantum yield of fluorescence or emission/excitation wavelength shift. Individual chemical Ca2+ fluorescent indicators are utilized for cytosolic calcium measurements in a wide variet |
https://en.wikipedia.org/wiki/Redox%20indicator | A redox indicator (also called an oxidation-reduction indicator) is an indicator which undergoes a definite color change at a specific electrode potential.
The requirement for fast and reversible color change means that the oxidation-reduction equilibrium for an indicator redox system needs to be established very quickly. Therefore, only a few classes of organic redox systems can be used for indicator purposes.
There are two common classes of redox indicators:
metal complexes of phenanthroline and bipyridine. In these systems, the metal changes oxidation state.
organic redox systems such as methylene blue. In these systems, a proton participates in the redox reaction. Therefore, sometimes redox indicators are also divided into two general groups: independent or dependent on pH.
The most common redox indicator are organic compounds.
Redox Indicator example:
The molecule 2,2'- Bipyridine is a redox Indicator. In solution, it changes from light blue to red at an electrode potential of 0.97 V.
pH independent
pH dependent
See also
Chemical analysis
pH indicator
Complexometric indicator |
https://en.wikipedia.org/wiki/Apple%20Developer | Apple Developer (formerly Apple Developer Connection) is Apple Inc.'s website for software development tools, application programming interfaces (APIs), and technical resources. It contains resources to help software developers write software for the macOS, iOS, iPadOS, watchOS, and tvOS platforms.
The applications are created in Xcode, or sometimes using other supported 3rd party programs. The apps can then be submitted to App Store Connect (formerly iTunes Connect), another one of Apple's website for approval the internal review team. Once approved, they can be distributed publicly via the respective app stores, i.e. App Store (iOS) for iOS and iPadOS apps, iMessage app store for Messages apps and Sticker pack apps, App Store (tvOS) for Apple TV apps, watchOS app store for Apple Watch apps with watchOS 6 and later, and via App Store (iOS) for earlier versions of watchOS. macOS apps are a notable exception to this, as they can be distributed similarly via Apple's Mac App Store or independently on the World Wide Web.
Programs
Mac
The Mac developer program is a way for developers of Apple's macOS operating system to distribute their apps through the Mac App Store. It costs US$99/year. Unlike iOS, developers are not required to sign up for the program in order to distribute their applications. Mac applications can freely be distributed via the developer's website and/or any other method of distribution excluding the Mac App Store. The Mac Developer Program also provides developers with resources to help them distribute their Mac applications.
Software leaks
There have been several leaks of secret Apple software through the prerelease program, most notably the Mac OS X 10.4 Tiger leaks, in which Apple sued three men who allegedly obtained advance copies of Mac OS X 10.4 prerelease builds from the site and leaked it to BitTorrent.
Attempted hacks
On July 18, 2013, an intruder attempted to access sensitive personal information on Apple's developer servers. The inf |
https://en.wikipedia.org/wiki/Darwin%20Centennial%20Celebration%20%281959%29 | The Darwin Centennial Celebration of 1959 was a worldwide celebration of the life and work of British naturalist Charles Darwin that marked the 150th anniversary of his birth (February 12, 1809), the 100th anniversary of the publication of On the Origin of Species (November 24, 1859), and the 125th anniversary of the second voyage of HMS Beagle. The major center of festivities and commemoration was the University of Chicago, which hosted a five-day event (November 24 to November 28), organized by anthropologist Sol Tax, that attracted over 2,500 registered participants from across the world. According to historian V. Betty Smocovitis, the Chicago celebration "outshone-and arguably may still outshine-all other scientific celebrations in the recent history of science."
The celebration took place in the wake of the evolutionary synthesis of the 1930s and 1940s and the emergence, by the mid-1950s, of an organized scientific discipline of evolutionary biology, and was an opportunity for biologists of many stripes to lay claim to the legacy of Darwin. It was also a chance for American biologists, and the American Society for the Study of Evolution, to out-compete parallel British events, and for the University of Chicago to assert its emerging position as an important scientific institution.
Planning
Planning for the Darwin centennial began in the mid-1950s. In 1955 the Darwin Anniversary Committee, Inc., which included a number of Darwin's descendants as honorary officers, formed to coordinate anniversary events worldwide. Various other organizations, including the Society for the Study of Evolution (SSE), the American Scientific Affiliation, various biological journals and scientific societies and institutions in many countries, also began planning independent activities and commemorative publications. After the evolutionary synthesis, whose founders sought to make genetics-based evolution by natural selection the central uniting principle of all biology, almost |
https://en.wikipedia.org/wiki/Quantum%20hydrodynamics | In condensed matter physics, quantum hydrodynamics is most generally the study of hydrodynamic-like systems which demonstrate quantum mechanical behavior. They arise in semiclassical mechanics in the study of metal and semiconductor devices, in which case being derived from the Boltzmann transport equation combined with Wigner quasiprobability distribution. In quantum chemistry they arise as solutions to chemical kinetic systems, in which case they are derived from the Schrödinger equation by way of Madelung equations.
An important system of study in quantum hydrodynamics is that of superfluidity. Some other topics of interest in quantum hydrodynamics are quantum turbulence, quantized vortices, second and third sound, and quantum solvents. The quantum hydrodynamic equation is an equation in Bohmian mechanics, which, it turns out, has a mathematical relationship to classical fluid dynamics (see Madelung equations).
Some common experimental applications of these studies are in liquid helium (3He and 4He), and of the interior of neutron stars and the quark–gluon plasma. Many famous scientists have worked in quantum hydrodynamics, including Richard Feynman, Lev Landau, and Pyotr Kapitsa.
See also
Hydrodynamic quantum analogs |
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