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https://en.wikipedia.org/wiki/Geoffrey%20Horrocks%20%28mathematician%29
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Geoffrey Horrocks (1932/33 Leicester – 12 September 2012) was a British mathematician working on vector bundles, who introduced the Horrocks construction used in the ADHM construction, and the Horrocks–Mumford bundle and monads.
He was a professor at Newcastle University until his retirement in 1998.
Publications
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https://en.wikipedia.org/wiki/ADHM%20construction
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In mathematical physics and gauge theory, the ADHM construction or monad construction is the construction of all instantons using methods of linear algebra by Michael Atiyah, Vladimir Drinfeld, Nigel Hitchin, Yuri I. Manin in their paper "Construction of Instantons."
ADHM data
The ADHM construction uses the following data:
complex vector spaces V and W of dimension k and N,
k × k complex matrices B1, B2, a k × N complex matrix I and a N × k complex matrix J,
a real moment map
a complex moment map
Then the ADHM construction claims that, given certain regularity conditions,
Given B1, B2, I, J such that , an anti-self-dual instanton in a SU(N) gauge theory with instanton number k can be constructed,
All anti-self-dual instantons can be obtained in this way and are in one-to-one correspondence with solutions up to a U(k) rotation which acts on each B in the adjoint representation and on I and J via the fundamental and antifundamental representations
The metric on the moduli space of instantons is that inherited from the flat metric on B, I and J.
Generalizations
Noncommutative instantons
In a noncommutative gauge theory, the ADHM construction is identical but the moment map is set equal to the self-dual projection of the noncommutativity matrix of the spacetime times the identity matrix. In this case instantons exist even when the gauge group is U(1). The noncommutative instantons were discovered by Nikita Nekrasov and Albert Schwarz in 1998.
Vortices
Setting B2 and J to zero, one obtains the classical moduli space of nonabelian vortices in a supersymmetric gauge theory with an equal number of colors and flavors, as was demonstrated in Vortices, instantons and branes. The generalization to greater numbers of flavors appeared in Solitons in the Higgs phase: The Moduli matrix approach. In both cases the Fayet–Iliopoulos term, which determines a squark condensate, plays the role of the noncommutativity parameter in the real moment map.
The constru
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https://en.wikipedia.org/wiki/Insectary%20plant
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Insectary plants are those that attract insects. As such, beneficial insectary plants are intentionally introduced into an ecosystem to increase pollen and nectar resources required by the natural enemies of the harmful or unwanted insects pests. Beyond an effective natural control of pests, the beneficial insects also assist in pollination.
The "friendly insects" include ladybeetles, bees, ground beetles, hoverflies, and parasitic wasps. Other animals that are frequently considered beneficial include lizards, spiders, toads, and hummingbirds. Beneficial insects are as much as ten times more abundant in the insectary plantings area. Mortality of scale insects (caused by natural enemies) can be double with insectary plantings. In addition, a diversity of insectary plants can increase the population of beneficial insects such that these levels can be sustained even when the insectary plants are removed or die off.
For maximum benefit in the garden, insectary plants can be grown alongside desired garden plants that do not have this benefit. The insects attracted to the insectary plants will also help the other nearby garden plants.
Many members of the family Apiaceae (formerly known as Umbelliferae) are excellent insectary plants. Fennel, angelica, coriander (cilantro), dill, and wild carrot all provide in great number the tiny flowers required by parasitic wasps. Various clovers, yarrow, and rue also attract parasitic and predatory insects. Low-growing plants, such as thyme, rosemary, or mint, provide shelter for ground beetles and other beneficial insects. Composite flowers (daisy and chamomile) and mints (spearmint, peppermint, or catnip) will attract predatory wasps, hoverflies, and robber flies. The wasps will catch caterpillars and grubs to feed their young, while the predatory and parasitic flies attack many kinds of insects, including leaf hoppers and caterpillars.
Other insectary plants include: mustard plants such as Brassica juncea, Phacelia tanacetifoli
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https://en.wikipedia.org/wiki/Robert%20A.%20Jarrow
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Robert Alan Jarrow is the Ronald P. and Susan E. Lynch Professor of Investment Management at the Johnson Graduate School of Management, Cornell University. Professor Jarrow is a co-creator of the Heath–Jarrow–Morton framework for pricing interest rate derivatives, a co-creator of the reduced form Jarrow–Turnbull credit risk models employed for pricing credit derivatives, and the creator of the forward price martingale measure. These tools and models are now the standards utilized for pricing and hedging in major investment and commercial banks.
He is on the advisory board of Mathematical Finance – a journal he co-started in 1989. He is also an associate or advisory editor for numerous other journals and serves on the board of directors of several firms and professional societies. He is currently both an IAFE senior fellow and an FDIC senior fellow. He has served as the Director for Research of Kamakura Corporation since 1995.
Professor Jarrow has been the recipient of numerous prizes and awards including the CBOE Pomerance Prize for Excellence in the Area of Options Research, the Graham and Dodd Scrolls Award, and the 1997 International Association of Financial Engineers IAFE/SunGard Financial Engineer of the Year Award. He is included in both the Fixed Income Analysts Society Hall of Fame and Risk Magazine's 50 member Hall of Fame.
Publications include five books - Options Pricing, Finance Theory, Modeling Fixed Income Securities and Interest Rate Options (second edition), Derivative Securities (second edition), and And Introduction to Derivative Securities, Financial Markets, and Risk Management - as well as over 100 publications in leading finance and economic journals.
He graduated magna cum laude from Duke University in 1974 with a major in mathematics, received an MBA from the Tuck School of Business at Dartmouth College in 1976 with highest distinction, and in 1979 he obtained a PhD in finance from the MIT Sloan School of Management under Robert C. M
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https://en.wikipedia.org/wiki/Loop%20entropy
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Loop entropy is the entropy lost upon bringing together two residues of a polymer within a prescribed distance. For a single loop, the entropy varies logarithmically with the number of residues in the loop
where is the Boltzmann constant and is a coefficient that depends on the properties of the polymer. This entropy formula corresponds to a power-law distribution for the probability of the residues contacting.
The loop entropy may also vary with the position of the contacting residues. Residues near the ends of the polymer are more likely to contact (quantitatively, have a lower ) than those in the middle (i.e., far from the ends), primarily due to excluded volume effects.
Wang-Uhlenbeck entropy
The loop entropy formula becomes more complicated with multiples loops, but may be determined for a Gaussian polymer using a matrix method developed by Wang and Uhlenbeck. Let there be contacts among the residues, which define loops of the polymers. The Wang-Uhlenbeck matrix is an symmetric, real matrix whose elements equal the number of common residues between loops and . The entropy of making the specified contacts equals
As an example, consider the entropy lost upon making the contacts between residues 26 and 84 and residues 58 and 110 in a polymer (cf. ribonuclease A). The first and second loops have lengths 58 (=84-26) and 52 (=110-58), respectively, and they have 26 (=84-58) residues in common. The corresponding Wang-Uhlenbeck matrix is
whose determinant is 2340. Taking the logarithm and multiplying by the constants gives the entropy.
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https://en.wikipedia.org/wiki/Laboratory%20informatics
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Laboratory informatics is the specialized application of information technology aimed at optimizing and extending laboratory operations. It encompasses data acquisition (e.g. through sensors and hardware or voice), instrument interfacing, laboratory networking, data processing, specialized data management systems (such as a chromatography data system), a laboratory information management system, scientific data management (including data mining and data warehousing), and knowledge management (including the use of an electronic lab notebook). It has become more prevalent with the rise of other "informatics" disciplines such as bioinformatics, cheminformatics and health informatics. Several graduate programs are focused on some form of laboratory informatics, often with a clinical emphasis. A closely related - some consider subsuming - field is laboratory automation.
Capability Areas
In the context of Public Health Laboratories, the Association of Public Health Laboratories has identified 19 areas for self-assessment of laboratory informatics in their Laboratories Efficiencies Initiative. These include the following Capability Areas.
Laboratory Test Request and Sample Receiving
Test Preparation, LIMS Processing, Test Results Recording and Verification
Report Preparation and Distribution
Laboratory Test Scheduling
Prescheduled Testing
Specimen and Sample Tracking/Chain of Custody
Media, Reagents, Controls: Manufacturing and Inventory
Interoperability and Data Exchange
Statistical Analysis and Surveillance
Billing for Laboratory Services
Contract and Grant Management
Training, Education and Resource Management
Laboratory Certifications/Licensing
Customer Relationship Management
Quality Control (QC) and Quality Assurance (QA) Management
Laboratory Safety and Accident Investigation
Laboratory Mutual Assistance/Disaster Recovery
Core IT Service Management: Hardware, Software and Services
Policies and Procedures, including Budgeting and Funding
Sub-to
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https://en.wikipedia.org/wiki/BrainMaps
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BrainMaps is an NIH-funded interactive zoomable high-resolution digital brain atlas and virtual microscope that is based on more than 140 million megapixels (140 terabytes) of scanned images of serial sections of both primate and non-primate brains and that is integrated with a high-speed database for querying and retrieving data about brain structure and function over the internet.
Currently featured are complete brain atlas datasets for 16 species; a few of which are: Macaca mulatta, Chlorocebus aethiops, Felis silvestris catus, Mus musculus, Rattus norvegicus, and Tyto alba.
The project's principal investigator was UC Davis neuroscientist Ted Jones from 2005 through 2011, after which the role was taken by W. Martin Usrey.
Description
BrainMaps uses multiresolution image formats for representing massive brain images, and a dHTML/Javascript front-end user interface for image navigation, both similar to the way that Google Maps works for geospatial data.
BrainMaps is one of the most massive online neuroscience databases and image repositories and features the highest-resolution whole brain atlas ever constructed.
Extensions to interactive 3-dimensional visualization have been developed through OpenGL-based desktop applications. Freely available image analysis tools enable end-users to datamine online images at the sub-neuronal level. BrainMaps has been used in both research and didactic settings.
Additional images
See also
List of neuroscience databases
Human Brain Project
NeuroNames
Mouse brain
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https://en.wikipedia.org/wiki/Frequency%20band
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A frequency band is an interval in the frequency domain, delimited by a lower frequency and an upper frequency. The term may refer to a radio band (such as wireless communication standards set by the International Telecommunication Union) or an interval of some other spectrum.
The frequency range of a system is the range over which it is considered to provide satisfactory performance, such as a useful level of signal with acceptable distortion characteristics. A listing of the upper and lower limits of frequency limits for a system is not useful without a criterion for what the range represents.
Many systems are characterized by the range of frequencies to which they respond. For example:
Musical instruments produce different ranges of notes within the hearing range.
The electromagnetic spectrum can be divided into many different ranges such as visible light, infrared or ultraviolet radiation, radio waves, X-rays and so on, and each of these ranges can in turn be divided into smaller ranges.
A radio communications signal must occupy a range of frequencies carrying most of its energy, called its bandwidth. A frequency band may represent one communication channel or be subdivided into many. Allocation of radio frequency ranges to different uses is a major function of radio spectrum allocation.
See also
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https://en.wikipedia.org/wiki/Langevin%20dynamics
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In physics, Langevin dynamics is an approach to the mathematical modeling of the dynamics of molecular systems. It was originally developed by French physicist Paul Langevin. The approach is characterized by the use of simplified models while accounting for omitted degrees of freedom by the use of stochastic differential equations. Langevin dynamics simulations are a kind of Monte Carlo simulation.
Overview
A real world molecular system is unlikely to be present in vacuum. Jostling of solvent or air molecules causes friction, and the occasional high velocity collision will perturb the system. Langevin dynamics attempts to extend molecular dynamics to allow for these effects. Also, Langevin dynamics allows temperature to be controlled like with a thermostat, thus approximating the canonical ensemble.
Langevin dynamics mimics the viscous aspect of a solvent. It does not fully model an implicit solvent; specifically, the model does not account for the electrostatic screening and also not for the hydrophobic effect. For denser solvents, hydrodynamic interactions are not captured via Langevin dynamics.
For a system of particles with masses , with coordinates that constitute a time-dependent random variable, the resulting Langevin equation is
where is the particle interaction potential; is the gradient operator such that is the force calculated from the particle interaction potentials; the dot is a time derivative such that is the velocity and is the acceleration; is the damping constant (units of reciprocal time), also known as the collision frequency; is the temperature, is Boltzmann's constant; and is a delta-correlated stationary Gaussian process with zero-mean, satisfying
Here, is the Dirac delta.
If the main objective is to control temperature, care should be exercised to use a small damping constant . As grows, it spans from the inertial all the way to the diffusive (Brownian) regime. The Langevin dynamics limit of non-inertia is commonly descr
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https://en.wikipedia.org/wiki/Choi%27s%20theorem%20on%20completely%20positive%20maps
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In mathematics, Choi's theorem on completely positive maps is a result that classifies completely positive maps between finite-dimensional (matrix) C*-algebras. An infinite-dimensional algebraic generalization of Choi's theorem is known as Belavkin's "Radon–Nikodym" theorem for completely positive maps.
Statement
Choi's theorem. Let be a linear map. The following are equivalent:
(i) is -positive (i.e. is positive whenever is positive).
(ii) The matrix with operator entries
is positive, where is the matrix with 1 in the -th entry and 0s elsewhere. (The matrix CΦ is sometimes called the Choi matrix of .)
(iii) is completely positive.
Proof
(i) implies (ii)
We observe that if
then E=E* and E2=nE, so E=n−1EE* which is positive. Therefore CΦ =(In ⊗ Φ)(E) is positive by the n-positivity of Φ.
(iii) implies (i)
This holds trivially.
(ii) implies (iii)
This mainly involves chasing the different ways of looking at Cnm×nm:
Let the eigenvector decomposition of CΦ be
where the vectors lie in Cnm . By assumption, each eigenvalue is non-negative so we can absorb the eigenvalues in the eigenvectors and redefine so that
The vector space Cnm can be viewed as the direct sum compatibly with the above identification
and the standard basis of Cn.
If Pk ∈ Cm × nm is projection onto the k-th copy of Cm, then Pk* ∈ Cnm×m is the inclusion of Cm as the k-th summand of the direct sum and
Now if the operators Vi ∈ Cm×n are defined on the k-th standard
basis vector ek of Cn by
then
Extending by linearity gives us
for any A ∈ Cn×n. Any map of this form is manifestly completely positive: the map is completely positive, and the sum (across ) of completely positive operators is again completely positive. Thus is completely positive, the desired result.
The above is essentially Choi's original proof. Alternative proofs have also been known.
Consequences
Kraus operators
In the context of quantum information theory, the operators {Vi} are called the Kraus operators (af
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https://en.wikipedia.org/wiki/Chemogenomics
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Chemogenomics, or chemical genomics, is the systematic screening of targeted chemical libraries of small molecules against individual drug target families (e.g., GPCRs, nuclear receptors, kinases, proteases, etc.) with the ultimate goal of identification of novel drugs and drug targets. Typically some members of a target library have been well characterized where both the function has been determined and compounds that modulate the function of those targets (ligands in the case of receptors, inhibitors of enzymes, or blockers of ion channels) have been identified. Other members of the target family may have unknown function with no known ligands and hence are classified as orphan receptors. By identifying screening hits that modulate the activity of the less well characterized members of the target family, the function of these novel targets can be elucidated. Furthermore, the hits for these targets can be used as a starting point for drug discovery. The completion of the human genome project has provided an abundance of potential targets for therapeutic intervention. Chemogenomics strives to study the intersection of all possible drugs on all of these potential targets.
A common method to construct a targeted chemical library is to include known ligands of at least one and preferably several members of the target family. Since a portion of ligands that were designed and synthesized to bind to one family member will also bind to additional family members, the compounds contained in a targeted chemical library should collectively bind to a high percentage of the target family.
Strategy
Chemogenomics integrates target and drug discovery by using active compounds, which function as ligands, as probes to characterize proteome functions. The interaction between a small compound and a protein induces a phenotype. Once the phenotype is characterized, we could associate a protein to a molecular event. Compared with genetics, chemogenomics techniques are able to m
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https://en.wikipedia.org/wiki/Urachus
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The urachus is a fibrous remnant of the allantois, a canal that drains the urinary bladder of the fetus that joins and runs within the umbilical cord. The fibrous remnant lies in the space of Retzius, between the transverse fascia anteriorly and the peritoneum posteriorly.
Development
The part of the urogenital sinus related to the bladder and urethra absorbs the ends of the Wolffian ducts and the associated ends of the renal diverticula. This gives rise to the trigone of the bladder and part of the prostatic urethra.
The remainder of this part of the urogenital sinus forms the body of the bladder and part of the prostatic urethra. The apex of the bladder stretches and is connected to the umbilicus as a narrow canal. This canal is initially open, but later closes as the urachus goes on to definitively form the median umbilical ligament.
Clinical significance
Failure of the inside of the urachus to be filled in leaves the urachus open. The telltale sign is leakage of urine through the umbilicus. This is often managed surgically. There are four anatomical causes:
Urachal cyst: there is no longer a connection between the bladder and the umbilicus, however a fluid filled cavity with uroepithelium lining persists between these two structures.
Urachal fistula: there is free communication between the bladder and umbilicus
Urachal diverticulum (vesicourachal diverticulum): the bladder exhibits outpouching
Urachal sinus: the pouch opens toward the umbilicus
The urachus is also subject to neoplasia. Urachal adenocarcinoma is histologically similar to adenocarcinoma of the bowel. Rarely, urachus carcinomas can metastasise to other regions of the body, including pelvic bones and the lung.
One urachal mass has been reported that was found to be a manifestation of IgG4-related disease.
Additional images
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https://en.wikipedia.org/wiki/Vitelline%20membrane
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The vitelline membrane or vitelline envelope is a structure surrounding the outer surface of the plasma membrane of an ovum (the oolemma) or, in some animals (e.g., birds), the extracellular yolk and the oolemma. It is composed mostly of protein fibers, with protein receptors needed for sperm binding which, in turn, are bound to sperm plasma membrane receptors. The species-specificity between these receptors contributes to prevention of breeding between different species.
It is called zona pellucida in mammals. Between the vitelline membrane and zona pellucida is a fluid-filled perivitelline space.
As soon as the spermatozoon fuses with the ovum, signal transduction occurs, resulting in an increase of cytoplasmic calcium ions. This itself triggers the cortical reaction, which results in depositing several substances onto the vitelline membrane through exocytosis of the cortical granules, transforming it into a hard layer called the “fertilization membrane”, which serves as a barrier inaccessible to other spermatozoa. This phenomenon is the slow block to polyspermy.
In insects, the vitelline membrane is called the vitelline envelope and is the inner lining of the chorion.
Structure and function
The vitelline membrane of the hen is made of two main protein layers that provide support for the yolk and separation from the albumen. The inner layer is known as the perivitelline lamina. It is a single layer that measures roughly 1 μm to 3.5 μm thick and is mainly composed of five glycoproteins that have been discovered to resemble glycoproteins of the zona pellucida in mammals involved in maintaining structure. The outer layer, known as the extravitelline lamina, has multiple sublayers which results in thickness that ranges from 0.3 μm to 9 μm. It is primarily composed of proteins, such as lysozyme, ovomucin and vitelline outer membrane proteins that are responsible for constructing the network of dense, thin protein fibres that establish the foundation for further gro
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https://en.wikipedia.org/wiki/18-electron%20rule
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The 18-electron rule is a chemical rule of thumb used primarily for predicting and rationalizing formulas for stable transition metal complexes, especially organometallic compounds. The rule is based on the fact that the valence orbitals in the electron configuration of transition metals consist of five (n−1)d orbitals, one ns orbital, and three np orbitals, where n is the principal quantum number. These orbitals can collectively accommodate 18 electrons as either bonding or non-bonding electron pairs. This means that the combination of these nine atomic orbitals with ligand orbitals creates nine molecular orbitals that are either metal-ligand bonding or non-bonding. When a metal complex has 18 valence electrons, it is said to have achieved the same electron configuration as the noble gas in the period, lending stability to the complex. Transition metal complexes that deviate from the rule are often interesting or useful because they tend to be more reactive. The rule is not helpful for complexes of metals that are not transition metals. The rule was first proposed by American chemist Irving Langmuir in 1921.
Applicability
The rule usefully predicts the formulas for low-spin complexes of the Cr, Mn, Fe, and Co triads. Well-known examples include ferrocene, iron pentacarbonyl, chromium carbonyl, and nickel carbonyl.
Ligands in a complex determine the applicability of the 18-electron rule. In general, complexes that obey the rule are composed at least partly of π-acceptor ligands (also known as π-acids). This kind of ligand exerts a very strong ligand field, which lowers the energies of the resultant molecular orbitals so that they are favorably occupied. Typical ligands include olefins, phosphines, and CO. Complexes of π-acids typically feature metal in a low-oxidation state. The relationship between oxidation state and the nature of the ligands is rationalized within the framework of π backbonding.
Consequences for reactivity
Compounds that obey the 18-electr
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https://en.wikipedia.org/wiki/Sorbitan%20monostearate
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Sorbitan monostearate is an ester of sorbitan (a sorbitol derivative) and stearic acid and is sometimes referred to as a synthetic wax.
Uses
Sorbitan monostearate is used in the manufacture of food and healthcare products as a non-ionic surfactant with emulsifying, dispersing, and wetting properties. It is also employed to create synthetic fibers, metal machining fluid, and as a brightener in the leather industry. Sorbitans are also known as "Spans".
Sorbitan monostearate has been approved by the European Union for use as a food additive (emulsifier) (E number: E 491). It is also approved for use by the British Pharmacopoeia.
See also
Polysorbate
Sorbitan tristearate (Span 65)
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https://en.wikipedia.org/wiki/Medial%20palpebral%20ligament
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The medial palpebral ligament (medial canthal tendon) is a ligament of the face. It attaches to the frontal process of the maxilla, the lacrimal groove, and the tarsus of each eyelid. It has a superficial (anterior) and a deep (posterior) layer, with many surrounding attachments. It connects the medial canthus of each eyelid to the medial part of the orbit. It is a useful point of fixation during eyelid reconstructive surgery.
Structure
The anterior attachment of the medial palpebral ligament is to the frontal process of the maxilla in front of the lacrimal groove (near the nasal bone and the frontal bone), and its posterior attachment is the lacrimal bone. Crossing the lacrimal sac, it divides into two parts, upper and lower, each attached to the medial end of the corresponding tarsus of each eyelid.
As the ligament crosses the lacrimal sac, a strong aponeurotic lamina is given off from its posterior surface; this expands over the sac, and is attached to the posterior lacrimal crest.
The medial palpebral ligament consists of a superficial (anterior) and a deep (posterior) layer. The superficial layer has a length of around 9.6 mm, a width of around 2.4 mm, and a thickness of around 4.5 mm. The deep layer has a length of around 3.7, a width of around 2.9, and a thickness of around 0.3 mm. Together, these have a strength of around 17 newtons, with most of this strength from the superficial layer.
Relations
The superior branch of the medial palpebral artery runs directly behind the medial palpebral ligament. Branches of the facial nerve, particularly the buccal branches, pass upwards over the medial palpebral ligament to reach the nose.
Function
The medial palpebral ligament connects the medial canthus of each eyelid to the medial part of the orbit.
Clinical significance
The medial palpebral ligament can be used as a point of fixation during eyelid reconstructive surgery, allowing for normal blinking.
History
The medial palpebral ligament has also been kn
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https://en.wikipedia.org/wiki/Container%20%28abstract%20data%20type%29
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In computer science, a container is a class or a data structure<ref>Paul E. Black (ed.), entry for data structure in Dictionary of Algorithms and Data Structures. US National Institute of Standards and Technology.15 December 2004. Accessed 4 Oct 2011.</ref> whose instances are collections of other objects. In other words, they store objects in an organized way that follows specific access rules.
The size of the container depends on the number of objects (elements) it contains. Underlying (inherited) implementations of various container types may vary in size, complexity and type of language, but in many cases they provide flexibility in choosing the right implementation for any given scenario.
Container data structures are commonly used in many types of programming languages.
Function and properties
Containers can be characterized by the following three properties:
access, that is the way of accessing the objects of the container. In the case of arrays, access is done with the array index. In the case of stacks, access is done according to the LIFO (last in, first out) order and in the case of queues it is done according to the FIFO (first in, first out) order;
storage, that is the way of storing the objects of the container;
traversal, that is the way of traversing the objects of the container.
Container classes are expected to implement CRUD-like methods to do the following:
create an empty container (constructor);
insert objects into the container;
delete objects from the container;
delete all the objects in the container (clear);
access the objects in the container;
access the number of objects in the container (count).
Containers are sometimes implemented in conjunction with iterators.
Types
Containers may be classified as either single-value containers or associative containers''.
Single-value containers store each object independently. Objects may be accessed directly, by a language loop construct (e.g. for loop) or with an iterator.
An ass
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https://en.wikipedia.org/wiki/Kruppel-like%20factors
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In molecular genetics, the Krüppel-like family of transcription factors (KLFs) are a set of eukaryotic C2H2 zinc finger DNA-binding proteins that regulate gene expression. This family has been expanded to also include the Sp transcription factor and related proteins, forming the Sp/KLF family.
Members
The following human genes encode Kruppel-like factors:
KLF1, KLF2, KLF3, KLF4, KLF5, KLF6, KLF7, KLF8, KLF9, KLF10, KLF11, KLF12, KLF13, KLF14, KLF15, KLF16, KLF17
The following genes are Sp factors:
Sp1, Sp2, Sp3, Sp4, Sp5, Sp6, Sp7, Sp8, and Sp9.
Note that although KLF14 was an alias for Sp6 (), it now refers to a protein () derived from KLF16 by a retrotransposon event.
Function and properties
KLF/Sps are a family of transcription factors that contain three carboxyl-terminal (C-terminal) C2H2-type zinc finger structural motifs that bind to the GC-rich regions in DNA and regulate various cellular functions, such as proliferation, differentiation, and apoptosis, as well as the development and homeostasis of several types of tissue. The C-terminal end binds to the promoter and enhancer regions of a gene. Each KLF also has a unique amino-terminal (N-terminal) end that acts as the functional domain that allows it to bind specifically to a certain partner. KLFs share the similar function of transcription regulation via the recruitment of regulatory proteins. These transcription factors have a conserved structural homology between mammalian species, which allow for similar function due to similar protein interaction motifs at the N-terminal domains. The C-terminal end is also highly conserved with both the first and second zinc finger have 25 amino acids, while the third has 23 amino acids. Each of the three zinc fingers recognize three unique base pairs for their DNA-binding sites, which together make the general form NCR CRC CCN (where N is any base and R is a purine). There is some evidence that positively-charged amino acids within the three zinc f
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https://en.wikipedia.org/wiki/Zygomatic%20process
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The zygomatic processes (aka. Malar) are three processes (protrusions) from other bones of the skull which each articulate with the zygomatic bone. The three processes are:
Zygomatic process of frontal bone from the frontal bone
Zygomatic process of maxilla from the maxilla
Zygomatic process of temporal bone from the temporal bone
The term zygomatic derives from the Greek Ζυγόμα, zygoma, meaning "yoke". The zygomatic process is occasionally referred to as the zygoma, but this term usually refers to the zygomatic bone or occasionally the zygomatic arch.
Zygomatic process of frontal bone
The supraorbital margin of the frontal bone ends laterally in its zygomatic process, which is strong and prominent, and articulates with the zygomatic bone. The zygomatic process of the frontal bone extends from the frontal bone laterally and inferiorly.
Zygomatic process of maxilla
The zygomatic process of the maxilla is a rough triangular eminence, situated at the angle of separation of the anterior, zygomatic, and orbital surfaces.
In front it forms part of the anterior surface.
Behind it is concave, and forms part of the infratemporal fossa.
Above it is rough and serrated for articulation with the zygomatic bone.
Below it presents the prominent arched border which marks the division between the anterior and infratemporal surfaces.
Zygomatic process of temporal bone
The zygomatic process of the temporal bone is a long, arched process projecting from the lower part of the squamous portion of the temporal bone. It articulates with the zygomatic bone.
This process is at first directed lateralward, its two surfaces looking upward and downward; it then appears as if twisted inward upon itself, and runs forward, its surfaces now looking medialward and lateralward.
The superior border is long, thin, and sharp, and serves for the attachment of the temporal fascia.
The inferior border, short, thick, and arched, has attached to it some fibers of the masseter.
The later
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https://en.wikipedia.org/wiki/Cation%E2%80%93%CF%80%20interaction
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Cation–π interaction is a noncovalent molecular interaction between the face of an electron-rich π system (e.g. benzene, ethylene, acetylene) and an adjacent cation (e.g. Li+, Na+). This interaction is an example of noncovalent bonding between a monopole (cation) and a quadrupole (π system). Bonding energies are significant, with solution-phase values falling within the same order of magnitude as hydrogen bonds and salt bridges. Similar to these other non-covalent bonds, cation–π interactions play an important role in nature, particularly in protein structure, molecular recognition and enzyme catalysis. The effect has also been observed and put to use in synthetic systems.
Origin of the effect
Benzene, the model π system, has no permanent dipole moment, as the contributions of the weakly polar carbon–hydrogen bonds cancel due to molecular symmetry. However, the electron-rich π system above and below the benzene ring hosts a partial negative charge. A counterbalancing positive charge is associated with the plane of the benzene atoms, resulting in an electric quadrupole (a pair of dipoles, aligned like a parallelogram so there is no net molecular dipole moment). The negatively charged region of the quadrupole can then interact favorably with positively charged species; a particularly strong effect is observed with cations of high charge density.
Nature of the cation–π interaction
The most studied cation–π interactions involve binding between an aromatic π system and an alkali metal or nitrogenous cation. The optimal interaction geometry places the cation in van der Waals contact with the aromatic ring, centered on top of the π face along the 6-fold axis. Studies have shown that electrostatics dominate interactions in simple systems, and relative binding energies correlate well with electrostatic potential energy.
The Electrostatic Model developed by Dougherty and coworkers describes trends in binding energy based on differences in electrostatic attraction. It wa
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https://en.wikipedia.org/wiki/Intermediate%20polar
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In astronomy, an intermediate polar (also called a DQ Herculis Star) is a type of cataclysmic variable, binary star system with a white dwarf and a cool main-sequence secondary star. In most cataclysmic variables, matter from the companion star is gravitationally stripped by the compact star and forms an accretion disk around it. In intermediate polar systems, the same general scenario applies except that the inner disk is disrupted by the magnetic field of the white dwarf.
The name "intermediate polar" is derived from the strength of the white dwarf's magnetic field, which is between that of non-magnetic cataclysmic variable systems and strongly magnetic systems. Non-magnetic systems exhibit full accretion disks, while strongly magnetic systems (called polars or AM Herculis systems) exhibit only accretion streams which directly impact the white dwarf's magnetosphere.
There were 26 confirmed intermediate polar systems as of 14 April 2006. This represents about 1% of the 1,830 total cataclysmic variable systems presented by Downes et al. (2006) in the Catalog of Cataclysmic Variables. Only two of them are brighter than 15th magnitude at minimum: the prototype DQ Herculis, and the unusual slow nova, GK Persei.
System structure
In intermediate polar systems, material stripped from a red dwarf secondary star flows into an accretion disk around the white dwarf, but the inner disk is truncated by the magnetic field of the white dwarf. In extreme instances, the disk can be fully disrupted, although this is uncommon. In the region where the disk is truncated, the gas in the disk begins to travel along the white dwarf's magnetic field lines, forming curved sheets of luminous material called accretion curtains. Disk material passes through the curtains and then accretes onto the white dwarf near one of its magnetic poles.
Physical Properties
Intermediate polar systems are strong x-ray emitters. The x-rays are generated by high velocity particles from the accretion
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https://en.wikipedia.org/wiki/Lacrimal%20punctum
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The lacrimal punctum (: puncta) or lacrimal point, is a minute opening on the summits of the lacrimal papillae, seen on the margins of the eyelids at the lateral extremity of the lacrimal lake. There are two lacrimal puncta in the medial (inside) portion of each eyelid. Normally, the puncta dip into the lacrimal lake.
Together, they function to collect tears produced by the lacrimal glands. The fluid is conveyed through the lacrimal canaliculi to the lacrimal sac, and thence via the nasolacrimal duct to the inferior nasal meatus of the nasal passage.
Additional images
See also
Imperforate lacrimal punctum
Lacrimal apparatus
Punctal plug
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https://en.wikipedia.org/wiki/Polar%20%28star%29
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In astronomy, a polar is a highly magnetic type of cataclysmic variable (CV) binary star system, originally known as an AM Herculis star after the prototype member AM Herculis. Like other CVs, polars contain two stars: an accreting white dwarf (WD), and a low-mass donor star (usually a red dwarf) which is transferring mass to the WD as a result of the WD's gravitational pull, overflowing its Roche lobe. Polars are distinguished from other CVs by the presence of a very strong magnetic field in the WD. Typical magnetic field strengths of polar systems are 10 million to 80 million gauss (1000–8000 teslas). The WD in the polar AN Ursae Majoris has the strongest known magnetic field among cataclysmic variables, with a field strength of 230 million gauss (23 kT).
Accretion mechanism
One of the most critical consequences of the WD's magnetism is that it synchronizes the rotational period of the WD with the orbital period of the binary; to first order, this means that the same side of the WD always faces the donor star. This synchronous rotation is considered a defining feature of polars. Additionally, the WD's magnetic field captures the accretion stream from the donor star before it can develop into an accretion disk. The capture of the accretion stream is known as threading, and it occurs when the magnetic pressure from the WD matches the stream's ram pressure. The captured material flows along the WD's magnetic field lines until it violently accretes onto the WD in a shock near one or more of the star's magnetic poles. This accretion region covers only a fraction of the WD's surface, but it can contribute half of the system's optical light. In addition to optical and near-infrared cyclotron radiation, the accretion region also produces X-rays due to the high temperature of gas within the shock, so polars are frequently brighter in X-rays than non-magnetic CVs.
Whereas accretion in a non-magnetic system is governed by viscosity within the accretion disk, accretion
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https://en.wikipedia.org/wiki/Butson-type%20Hadamard%20matrix
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In mathematics, a complex Hadamard matrix H of size N with all its columns (rows) mutually orthogonal, belongs to the Butson-type H(q, N) if all its elements are powers of q-th root of unity,
Existence
If p is prime and , then can exist
only for with integer m and
it is conjectured they exist for all such cases
with . For , the corresponding conjecture is existence for all multiples of 4.
In general, the problem of finding all sets
such that the Butson - type matrices
exist, remains open.
Examples
contains real Hadamard matrices of size N,
contains Hadamard matrices composed of - such matrices were called by Turyn, complex Hadamard matrices.
in the limit one can approximate all complex Hadamard matrices.
Fourier matrices
belong to the Butson-type,
while
, where
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https://en.wikipedia.org/wiki/Antihelix
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The antihelix (anthelix) is a part of the visible ear; the pinna.
The antihelix is a curved prominence of cartilage parallel with and in front of the helix on the pinna.
The antihelix divides above into two legs or crura; the crura antihelicis, between which is a triangular depression, the fossa triangularis.
Additional images
External links
() (#5)
Auditory system
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https://en.wikipedia.org/wiki/Antitragus
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The antitragus is a feature of mammalian ear anatomy.
In humans, it is a small tubercle on the visible part of the ear, the pinna. The antitragus is located just above the earlobe and points anteriorly. It is separated from the tragus by the intertragic notch.
The antitragicus muscle, an intrinsic muscle of the ear, arises from the outer part of the antitragus.
The antitragus can be much larger in some other species, most notably bats.
The antitragus is sometimes pierced.
Additional images
See also
Antitragus piercing
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https://en.wikipedia.org/wiki/Ponticulus
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The eminentia conchae is crossed by a vertical ridge, the ponticulus, which gives attachment to the Auricularis posterior muscle.
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https://en.wikipedia.org/wiki/Pierce%20oscillator
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The Pierce oscillator is a type of electronic oscillator particularly well-suited for use in piezoelectric crystal oscillator circuits. Named for its inventor, George W. Pierce (1872–1956), the Pierce oscillator is a derivative of the Colpitts oscillator. Virtually all digital IC clock oscillators are of Pierce type, as the circuit can be implemented using a minimum of components: a single digital inverter, one resistor, two capacitors, and the quartz crystal, which acts as a highly selective filter element. The low manufacturing cost of this circuit and the outstanding frequency stability of the quartz crystal give it an advantage over other designs in many consumer electronics applications.
Operation
If the circuit consists of perfect lossless components, the signal on C1 and C2 will be proportional to the impedance of each, and the ratio of the signal voltages at C1 and C2 will be C2/C1. With C1 and C2 equal size (a common configuration), the current in C1 to C2 would be exactly equal, but out of phase, requiring no current from the amplifier or voltage gain from the amplifier, and allowing a high output impedance amplifier, or the use of an isolating series resistance in the amplifier output. Normal crystals are lossless enough to make this a reasonable approximation: the amplifier does not drive the resonant circuit, but merely stays in sync with it, providing enough power to match losses.
A series resistor is occasionally shown in the amplifier output. When used, a series resistor reduces loop gain, and amplifier gain must be increased to restore total loop gain to unity. The purpose of using such a resistor in the amplifier circuit is to increase phase shift at startup, or when the crystal circuit is pulled out of phase by loading, and to eliminate the effects of amplifier non-linearity and of crystal overtones or spurious modes. It is not part of the basic operation of the Pierce topology.
Biasing resistor
R1 acts as a feedback resistor, biasing the i
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https://en.wikipedia.org/wiki/Corpuscles%20of%20Herbst
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The corpuscles of Herbst or Herbst corpuscles are nerve-endings similar to the Pacinian corpuscle, found in the mucous membrane of the tongue, in pits on the beak and in other parts of the bodies of birds. They differ from Pacinian corpuscles in being smaller and more elongated, in having thinner and more closely placed capsules, and in that the axis-cylinder in the central clear space is encircled by a continuous row of nuclei. They are named after the German embryologist Curt Alfred Herbst.
In many wading birds, a large number of Herbst corpuscles are found embedded in pits on the mandible that are believed to enable birds to sense prey under wet sand or soil.
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https://en.wikipedia.org/wiki/Medically%20unexplained%20physical%20symptoms
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Medically unexplained physical symptoms (MUPS or MUS) are symptoms for which a treating physician or other healthcare providers have found no medical cause, or whose cause remains contested. In its strictest sense, the term simply means that the cause for the symptoms is unknown or disputed—there is no scientific consensus. Not all medically unexplained symptoms are influenced by identifiable psychological factors. However, in practice, most physicians and authors who use the term consider that the symptoms most likely arise from psychological causes. Typically, the possibility that MUPS are caused by prescription drugs or other drugs is ignored. It is estimated that between 15% and 30% of all primary care consultations are for medically unexplained symptoms. A large Canadian community survey revealed that the most common medically unexplained symptoms are musculoskeletal pain, ear, nose, and throat symptoms, abdominal pain and gastrointestinal symptoms, fatigue, and dizziness. The term MUPS can also be used to refer to syndromes whose etiology remains contested, including chronic fatigue syndrome, fibromyalgia, multiple chemical sensitivity and Gulf War illness.
The term medically unexplained symptoms is in some cases treated as synonymous to older terms such as psychosomatic symptoms, conversion disorders, somatic symptoms, somatisations or somatoform disorders; as well as contemporary terms such as functional disorders, bodily distress, and persistent physical symptoms. The plethora of terms reflects imprecision and uncertainty in their definition, controversy, and care taken to avoid stigmatising affected people. Risk factors for medically unexplained symptoms are complex and include both psychological and organic features, and such symptoms are often accompanied by other somatic symptoms attributable to organic disease. As such it is recognised that the boundary defining symptoms as medically unexplained is increasingly becoming blurred.
Women are signific
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https://en.wikipedia.org/wiki/Apple%20cider%20vinegar
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Apple cider vinegar, or cider vinegar, is a vinegar made from fermented apple juice, and used in salad dressings, marinades, vinaigrettes, food preservatives, and chutneys. It is made by crushing apples, then squeezing out the juice. Bacteria and yeast are added to the liquid to start the alcoholic fermentation process, which converts the sugars to alcohol. In a second fermentation step, the alcohol is converted into vinegar by acetic acid-forming bacteria (Acetobacter species). Acetic acid and malic acid combine to give vinegar its sour taste.
There is no high-quality clinical evidence that regular consumption of apple cider vinegar helps to maintain or lose body weight, or is effective to manage blood glucose and lipid levels.
Nutrition
Apple cider vinegar is 94% water and 5% acetic acid with 1% carbohydrates and no fat or protein (table). In a 100 gram (mL) reference amount, it provides 22 calories, with negligible content of micronutrients.
Processing
Apples are loaded onto a processing belt where they are washed, crushed, pressed, and the juice separated. The material is stored in a submerged tank where the first fermentation process begins through which oxygen is supplied. Alcoholic fermentation is completed using the bacterial strain acetobacter, which converts the ethanol to acetic acid yielding vinegar. The "mother" is an undefined microbial culture left in the vinegar prior to distilling and pasteurization.
Health effects
Despite its history of use in traditional medicine, there is no good evidence to support any health claims – such as for weight loss, glycemic control or skin infections – in humans, and its use is not recommended for any indication in medical guidelines of major public health organizations or regulatory agencies.
Safety concerns
Although low-level consumption of apple cider vinegar is of low risk, particularly if it is diluted, reported adverse effects include esophageal damage, tooth enamel erosion, and excessive burping, fl
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https://en.wikipedia.org/wiki/Scalar%20field%20theory
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In theoretical physics, scalar field theory can refer to a relativistically invariant classical or quantum theory of scalar fields. A scalar field is invariant under any Lorentz transformation.
The only fundamental scalar quantum field that has been observed in nature is the Higgs field. However, scalar quantum fields feature in the effective field theory descriptions of many physical phenomena. An example is the pion, which is actually a pseudoscalar.
Since they do not involve polarization complications, scalar fields are often the easiest to appreciate second quantization through. For this reason, scalar field theories are often used for purposes of introduction of novel concepts and techniques.
The signature of the metric employed below is .
Classical scalar field theory
A general reference for this section is Ramond, Pierre (2001-12-21). Field Theory: A Modern Primer (Second Edition). USA: Westview Press. , Ch 1.
Linear (free) theory
The most basic scalar field theory is the linear theory. Through the Fourier decomposition of the fields, it represents the normal modes of an infinity of coupled oscillators where the continuum limit of the oscillator index i is now denoted by . The action for the free relativistic scalar field theory is then
where is known as a Lagrangian density; for the three spatial coordinates; is the Kronecker delta function; and for the -th coordinate .
This is an example of a quadratic action, since each of the terms is quadratic in the field, . The term proportional to is sometimes known as a mass term, due to its subsequent interpretation, in the quantized version of this theory, in terms of particle mass.
The equation of motion for this theory is obtained by extremizing the action above. It takes the following form, linear in ,
where ∇2 is the Laplace operator. This is the Klein–Gordon equation, with the interpretation as a classical field equation, rather than as a quantum-mechanical wave equation.
Nonlinear (int
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https://en.wikipedia.org/wiki/Beta-alumina%20solid%20electrolyte
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Beta-alumina solid electrolyte (BASE) is a fast ion conductor material used as a membrane in several types of molten salt electrochemical cell. Currently there is no known substitute available. β-Alumina exhibits an unusual layered crystal structure which enables very fast ion transport. β-Alumina is not an isomorphic form of aluminium oxide (Al2O3), but a sodium polyaluminate. It is a hard polycrystalline ceramic, which, when prepared as an electrolyte, is complexed with a mobile ion, such as Na+, K+, Li+, Ag+, H+, Pb2+, Sr2+ or Ba2+ depending on the application. β-Alumina is a good conductor of its mobile ion yet allows no non-ionic (i.e., electronic) conductivity. The crystal structure of the β-alumina provides an essential rigid framework with channels along which the ionic species of the solid can migrate. Ion transport involves hopping from site to site along these channels. Since the 1970's this technology has been thoroughly developed, resulting in interesting applications. Its special characteristics on ion and electrical conductivity make this material extremely interesting in the field of energy storage.
Solid electrolyte
β-alumina is a solid electrolyte. Solid-state electrolytes are solids with high ionic conductivity, comparable to those of molten salts. Solid-state electrolytes have applications in electrical energy storage and various sensors. They can be used in supercapacitors, fuel cells and solid-state batteries, substituting liquid electrolytes used in for example the lithium-ion battery. The solid electrolyte contains highly mobile ions, allowing the movement of ions. The ions move by hopping through the otherwise rigid crystal. The main advantage of solid electrolytes over liquid ones are increased safety and higher power density.
History
BASE was first developed by researchers at the Ford Motor Company, in the search for a storage device for electric vehicles while developing the sodium–sulfur battery. The compound β-alumina was already
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https://en.wikipedia.org/wiki/Naimark%27s%20dilation%20theorem
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In operator theory, Naimark's dilation theorem is a result that characterizes positive operator valued measures. It can be viewed as a consequence of Stinespring's dilation theorem.
Some preliminary notions
Let X be a compact Hausdorff space, H be a Hilbert space, and L(H) the Banach space of bounded operators on H. A mapping E from the Borel σ-algebra on X to is called an operator-valued measure if it is weakly countably additive, that is, for any disjoint sequence of Borel sets , we have
for all x and y. Some terminology for describing such measures are:
E is called regular if the scalar valued measure
is a regular Borel measure, meaning all compact sets have finite total variation and the measure of a set can be approximated by those of open sets.
E is called bounded if .
E is called positive if E(B) is a positive operator for all B.
E is called self-adjoint if E(B) is self-adjoint for all B.
E is called spectral if it is self-adjoint and for all .
We will assume throughout that E is regular.
Let C(X) denote the abelian C*-algebra of continuous functions on X. If E is regular and bounded, it induces a map in the obvious way:
The boundedness of E implies, for all h of unit norm
This shows is a bounded operator for all f, and itself is a bounded linear map as well.
The properties of are directly related to those of E:
If E is positive, then , viewed as a map between C*-algebras, is also positive.
is a homomorphism if, by definition, for all continuous f on X and ,
Take f and g to be indicator functions of Borel sets and we see that is a homomorphism if and only if E is spectral.
Similarly, to say respects the * operation means
The LHS is
and the RHS is
So, taking f a sequence of continuous functions increasing to the indicator function of B, we get , i.e. E(B) is self adjoint.
Combining the previous two facts gives the conclusion that is a *-homomorphism if and only if E is spectral and self adjoint. (When E is spectral and se
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https://en.wikipedia.org/wiki/Computable%20ordinal
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In mathematics, specifically computability and set theory, an ordinal is said to be computable or recursive if there is a computable well-ordering of a computable subset of the natural numbers having the order type .
It is easy to check that is computable. The successor of a computable ordinal is computable, and the set of all computable ordinals is closed downwards.
The supremum of all computable ordinals is called the Church–Kleene ordinal, the first nonrecursive ordinal, and denoted by . The Church–Kleene ordinal is a limit ordinal. An ordinal is computable if and only if it is smaller than . Since there are only countably many computable relations, there are also only countably many computable ordinals. Thus, is countable.
The computable ordinals are exactly the ordinals that have an ordinal notation in Kleene's .
See also
Arithmetical hierarchy
Large countable ordinal
Ordinal analysis
Ordinal notation
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https://en.wikipedia.org/wiki/Contact%20shot
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A contact shot is a gunshot wound incurred while the muzzle of the firearm is in direct contact with the body at the moment of discharge. Contact shots are often the result of close-range gunfights, suicide, or execution.
Terminal effects
Wounds caused by contact shots are devastating, as the body absorbs the entire discharge of the cartridge, not just the projectile. In this case the injection of rapidly expanding propellant gasses may cause significantly more damage than the bullet itself. Even a blank cartridge can very easily cause lethal wounds if fired in contact with the body, so powerheads, which are intended to fire at contact range, are still very effective when loaded with blanks, while being relatively safe if accidentally discharged from a distance.
Firearms such as muzzleloaders and shotguns often have additional materials in the shot, such as a patch or wadding. While they are generally too lightweight to penetrate at longer ranges, they will penetrate in a contact shot. Since these are often made of porous materials such as cloth and cardboard, there is a significantly elevated risk of infection from the wound.
Characteristics
In the field of forensic ballistics, the characteristics of a contact shot are often an important part of recreating a shooting. A contact shot produces a distinctive wound, with extensive tissue damage from the burning propellant. Unlike a shot from point-blank range, the powder burns will cover a very small area right around the entry wound; often there will be a distinct pattern, called tattooing. Star-shaped tattooing is often caused by the rifling in the gun barrel, and distinct patterns may also be made by flash suppressors or muzzle brakes. The shape of the tattooing may help identify the firearm used.
In many cases, the body's absorption of the muzzle blast will act as a silencer, trapping the propellant gases under the skin and muffling the sound of the shot.
See also
Captive bolt pistol, a device designed to
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https://en.wikipedia.org/wiki/Obturator%20fascia
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The obturator fascia, or fascia of the internal obturator muscle, covers the pelvic surface of that muscle and is attached around the margin of its origin.
Above, it is loosely connected to the back part of the arcuate line, and here it is continuous with the iliac fascia.
In front of this, as it follows the line of origin of the internal obturator, it gradually separates from the iliac fascia and the continuity between the two is retained only through the periosteum.
It arches beneath the obturator vessels and nerve, completing the obturator canal, and at the front of the pelvis is attached to the back of the superior ramus of the pubis.
Below, the obturator fascia is attached to the falciform process of the sacrotuberous ligament and to the pubic arch, where it becomes continuous with the superior fascia of the urogenital diaphragm.
Behind, it is prolonged into the gluteal region.
The internal pudendal vessels and pudendal nerve cross the pelvic surface of the internal obturator and are enclosed in a special canal—Alcock’s canal—formed by the obturator fascia.
The iliococcygeus portion of the levator ani attaches to the lateral walls of the pelvis via the obturator fascia through the tendinous arch of the obturator fascia.
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https://en.wikipedia.org/wiki/Ricoh%202A03
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The Ricoh 2A03 or RP2A03 (NTSC version) / Ricoh 2A07 or RP2A07 (PAL version) is an 8-bit microprocessor manufactured by Ricoh for the Nintendo Entertainment System video game console. It was also used as a sound chip and secondary CPU by Nintendo's arcade games Punch-Out!! and Donkey Kong 3.
Technical details
The Ricoh 2A03 contains a second-sourced MOS Technology 6502 core, modified to disable the 6502's binary-coded decimal mode (possibly to avoid a MOS Technology patent). It also integrates a programmable sound generator (also known as APU, featuring twenty two memory-mapped I/O registers), rudimentary DMA, and game controller polling.
Sound hardware
The Ricoh 2A03's sound hardware has 5 channels, separated into two APUs (Audio Processing Units). The first APU contains two general purpose pulse channels with 4 duty cycles, and the second APU contains a triangle wave generator, an LFSR-based Noise generator, and a 1-bit Delta modulation-encoded PCM (DPCM) channel. While a majority of the NES library uses only 4 channels, later games use the 5th DPCM channel due to cartridge memory expansions becoming cheaper. For example, Super Mario Bros. 3 uses the DPCM channel for simple drum sounds, while Journey to Silius uses it for sampled basslines. An interesting quirk of the DPCM channel is that the bit order is reversed compared to what is normally expected for 1-bit PCM. Many developers were unaware of this detail, causing samples to be distorted during playback.
The output of each channel is mixed non-linearly in their respective APU before being combined. On Famicom and Dendy systems, expansion sound chips may add their own sound to the output via a pin on the game cartridge. Expansion audio capabilities were removed from international NES systems, but can be restored by modifying the expansion port located on the bottom of the system.
Regional variations
PAL versions of the NES (sold in Europe, Asia, and Australia) use the Ricoh 2A07 or RP2A07 processor, whic
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https://en.wikipedia.org/wiki/Anococcygeal%20body
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The anococcygeal body (anococcygeal ligament, or anococcygeal raphe) is a fibrous median raphe in the floor of the pelvis, which extends between the coccyx and the margin of the anus. It is composed of fibers of the levator ani muscle that unite with the muscle of the opposite side, muscle fibres from external anal sphincter, and fibrous connective tissue.
The fibers of the levator ani pass downward and backward to the middle line of the floor of the pelvis; the most posterior are inserted into the side of the last two segments of the coccyx; those placed more anteriorly unite with the muscle of the opposite side, in the anococcygeal body.
See also
Iliococcygeal raphe
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https://en.wikipedia.org/wiki/Iliac%20fascia
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The iliac fascia (or Abernethy's fascia) is the fascia overlying the iliacus muscle.
Superiorly and laterally, the iliac fascia is attached to the inner aspect of the iliac crest; inferiorly and laterally, it extends into the thigh to unite with the femoral sheath; medially, it attaches to the periosteum of the ilium and iliopubic eminence near the linea terminalis, and blends with the psoas fascia and - over the quadratus lumborum muscle - with the anterior layer of thoracolumbar fascia.
The iliac fascia overlies the femoral nerve, and lateral femoral cutaneous nerve.
Anatomy
It has the following connections:
laterally, to the whole length of the inner lip of the iliac crest.
medially, to the linea terminalis of the lesser pelvis, where it is continuous with the periosteum.
At the iliopectineal eminence it receives the tendon of insertion of the Psoas minor, when that muscle exists.
Lateral to the femoral vessels it is intimately connected to the posterior margin of the inguinal ligament, and is continuous with the transversalis fascia.
Immediately lateral to the femoral vessels the iliac fascia is prolonged backward and medialward from the inguinal ligament as a band, the iliopectineal fascia, which is attached to the iliopectineal eminence.
This fascia divides the space between the inguinal ligament and the hip bone into two lacunæ or compartments:
the medial vascular lacuna transmits the femoral vessels.
the lateral muscular lacuna transmits the Psoas major and Iliacus and the femoral nerve.
Medial to the vessels the iliac fascia is attached to the pectineal line behind the conjoint tendon, where it is again continuous with the transversalis fascia.
See also
Fascia iliaca block
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https://en.wikipedia.org/wiki/Roundness
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Roundness is the measure of how closely the shape of an object approaches that of a mathematically perfect circle. Roundness applies in two dimensions, such as the cross sectional circles along a cylindrical object such as a shaft or a cylindrical roller for a bearing. In geometric dimensioning and tolerancing, control of a cylinder can also include its fidelity to the longitudinal axis, yielding cylindricity. The analogue of roundness in three dimensions (that is, for spheres) is sphericity.
Roundness is dominated by the shape's gross features rather than the definition of its edges and corners, or the surface roughness of a manufactured object. A smooth ellipse can have low roundness, if its eccentricity is large. Regular polygons increase their roundness with increasing numbers of sides, even though they are still sharp-edged.
In geology and the study of sediments (where three-dimensional particles are most important), roundness is considered to be the measurement of surface roughness and the overall shape is described by sphericity.
Simple definitions
The ISO definition of roundness is the ratio of the radii of inscribed and circumscribed circles, i.e. the maximum and minimum sizes for circles that are just sufficient to fit inside and to enclose the shape.
Diameter
Having a constant diameter, measured at varying angles around the shape, is often considered to be a simple measurement of roundness. This is misleading.
Although constant diameter is a necessary condition for roundness, it is not a sufficient condition for roundness: shapes exist that have constant diameter but are far from round. Mathematical shapes such as the Reuleaux triangle and, an everyday example, the British 50p coin demonstrate this.
Radial displacements
Roundness does not describe radial displacements of a shape from some notional centre point, merely the overall shape.
This is important in manufacturing, such as for crankshafts and similar objects, where not only the roundnes
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https://en.wikipedia.org/wiki/Femoral%20sheath
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The femoral sheath (also called the crural sheath) is a funnel-shaped downward extension of abdominal fascia within which the femoral artery and femoral vein pass between the abdomen and the thigh. The femoral sheath is subdivided by two vertical partitions to form three compartments (medial, intermediate, and lateral); the medial compartment is known as the femoral canal and contains lymphatic vessels and a lymph node, whereas the intermediate canal and the lateral canal accommodate the femoral vein and the femoral artery (respectively). Some neurovascular structures perforate the femoral sheath. Topographically, the femoral sheath is contained within the femoral triangle.
Structure
The femoral sheath is funnel-shaped fascial structure, with the wide end directed superior-ward. The femoral sheath is formed by an inferior-ward prolongation - posterior to the inguinal ligament - of abdominal fascia, with transverse fascia being continued down anterior to the femoral vessels, and iliac fascia posterior to these. The femoral sheath is strengthened anteriorly by the iliopubic tract. The narrowed inferior/distal end of the femoral sheath concludes by blending with the tunica adventitia of the femoral vessels about 4 cm inferior to the inguinal ligament.
The lateral wall of the sheath is vertical and is perforated by the lumboinguinal nerve; the medial wall is directed/oriented obliquely inferolaterally and is perforated by the great saphenous vein, and by Lymphatic vessel.
The femoral sheath is contained in the femoral triangle.
Compartments and contents
The sheath is divided by two vertical partitions which stretch between its anterior and posterior walls:
The (smallest) medial compartment is named the femoral canal, and contains some lymphatic vessels and a lymph gland embedded in a small amount of areolar tissue.
The intermediate compartment contains the femoral vein.
The lateral compartment contains the femoral artery.
Function
The femoral sheath allows f
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https://en.wikipedia.org/wiki/Lacunar%20ligament
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The lacunar ligament, also named Gimbernat’s ligament, is a ligament in the inguinal region. It connects the inguinal ligament to the pectineal ligament, near the point where they both insert on the pubic tubercle.
Structure
The lacunar ligament is the part of the aponeurosis of the external oblique muscle that is reflected backward and laterally and is attached to the pectineal line of the pubis.
It is about 1.25 cm. long, larger in the male than in the female, almost horizontal in direction in the erect posture, and of a triangular form with the base directed laterally.
Its base is concave, thin, and sharp, and forms the medial boundary of the femoral ring. Its apex corresponds to the pubic tubercle.
Its posterior margin is attached to the pectineal line, and is continuous with the pectineal ligament. Its anterior margin is attached to the inguinal ligament.
Its surfaces are directed upward and downward.
Clinical significance
The lacunar ligament is the only boundary of the femoral canal that can be cut during surgery to release a femoral hernia. Care must be taken when doing so as up to 25% of people have an aberrant obturator artery (corona mortis) which can cause significant bleeding.
History
The lacunar ligament is sometimes called Gimbernat's ligament after Antoni de Gimbernat.
Additional images
See also
Inguinal ligament
Pectineal ligament
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https://en.wikipedia.org/wiki/Lumboinguinal%20nerve
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The lumboinguinal nerve, also known as the femoral or crural branch of genitofemoral, is a nerve in the abdomen. The lumboinguinal nerve is a branch of the genitofemoral nerve. The "femoral" part supplies skin to the femoral triangle area.
Structure
The lumboinguinal nerve arises from the genitofemoral nerve. It descends alongside the external iliac artery, sending a few filaments around it, and, passing beneath the inguinal ligament, enters the sheath of the femoral vessels, lying superficial and lateral to the femoral artery. Here, it pierces the anterior layer of the sheath of the vessels and the fascia lata, and supplies the skin of the anterior surface of the upper part of the thigh.
On the front of the thigh it communicates with the anterior cutaneous branches of the femoral nerve.
A few filaments from the lumboinguinal nerve may be traced to the femoral artery.
Additional images
See also
Genitofemoral nerve
External links
Photo of model at Waynesburg College
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https://en.wikipedia.org/wiki/Iliopubic%20tract
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The iliopubic tract is a thickened band of fibers curving over the external iliac vessels, at the spot where they become femoral, on the abdominal side of the inguinal ligaments and loosely connected with it. It is apparently a thickening of the transversalis fascia joined laterally to the iliac crest, and arching across the front of the femoral sheath to be inserted by a broad attachment into the pubic tubercle and pectineal line, behind the conjoint tendon. In some subjects this structure is not very prominently marked, and not infrequently it is altogether wanting. It can be of clinical significance in hernia repair.
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https://en.wikipedia.org/wiki/Newisys
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Newisys was an American technology company. At various times it sold computers for data centers (known as servers), and computer data storage products.
It operated as a subsidiary of Sanmina Corporation since 2004.
History
Newisys was founded in July 2000 by Claymon A. Cipione and Phillip Doyce Hester, both from IBM. It was originally based in Austin, Texas.
By the end of 2000, almost $28 million in venture capital funding was obtained from New Enterprise Associates, Austin Ventures, and Advanced Micro Devices (AMD).
By 2002, they gave demonstrations of server using 64-bit AMD processors.
Another round of about $23 million funding was announced in November 2002, increased to $25 million in February 2003.
In July 2003, Sanmina-SCI (which had been a manufacturing partner) announced it would acquire Newisys for an undisclosed amount.
Newisys became an original design manufacturer for Sanminia.
In 2005, Hester left to become the chief technical officer of AMD until 2008, and Cipione also left to join AMD to become chief information officer.
In August 2005, a network-attached storage server product called the NA-1400 was announced, although shipments were reported to be delayed. It used an XScale 80219 processor from Intel.
In November 2005, Newisys announced an integrated circuit call the AMD Horus, which allowed servers to be built with large numbers of AMD Opteron processors.
In January 2006, the company acquired the block storage division of Adaptec, located in Colorado Springs, Colorado.
In May 2007, the server portion of the company was shut down, leaving storage (developed in Colorado) as the main focus.
Newisys returned to the server market in 2013 by adding Intel based servers into their storage products.
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https://en.wikipedia.org/wiki/Piston%20motion%20equations
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The reciprocating motion of a non-offset piston connected to a rotating crank through a connecting rod (as would be found in internal combustion engines) can be expressed by equations of motion. This article shows how these equations of motion can be derived using calculus as functions of angle (angle domain) and of time (time domain).
Crankshaft geometry
The geometry of the system consisting of the piston, rod and crank is represented as shown in the following diagram:
Definitions
From the geometry shown in the diagram above, the following variables are defined:
rod length (distance between piston pin and crank pin)
crank radius (distance between crank center and crank pin, i.e. half stroke)
crank angle (from cylinder bore centerline at TDC)
piston pin position (distance upward from crank center along cylinder bore centerline)
The following variables are also defined:
piston pin velocity (upward from crank center along cylinder bore centerline)
piston pin acceleration (upward from crank center along cylinder bore centerline)
crank angular velocity (in the same direction/sense as crank angle )
Angular velocity
The frequency (Hz) of the crankshaft's rotation is related to the engine's speed (revolutions per minute) as follows:
So the angular velocity (radians/s) of the crankshaft is:
Triangle relation
As shown in the diagram, the crank pin, crank center and piston pin form triangle NOP.
By the cosine law it is seen that:
where and are constant and varies as changes.
Equations with respect to angular position (Angle Domain)
Angle domain equations are expressed as functions of angle.
Deriving angle domain equations
The angle domain equations of the piston's reciprocating motion are derived from the system's geometry equations as follows.
Position
Position with respect to crank angle (from the triangle relation, completing the square, utilizing the Pythagorean identity, and rearranging):
Velocity
Velocity with respect to crank angle (take
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https://en.wikipedia.org/wiki/External%20iliac%20lymph%20nodes
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The external iliac lymph nodes are lymph nodes, from eight to ten in number, that lie along the external iliac vessels.
They are arranged in three groups, one on the lateral, another on the medial, and a third on the anterior aspect of the vessels; the third group is, however, sometimes absent.
Their principal afferents are derived from the inguinal lymph nodes, the deep lymphatics of the abdominal wall below the umbilicus and of the adductor region of the thigh, and the lymphatics from the glans penis, glans clitoridis, the membranous urethra, the prostate, the fundus of the urinary bladder, the cervix uteri, and upper part of the vagina.
Additional images
See also
Internal iliac lymph nodes
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https://en.wikipedia.org/wiki/Conserved%20name
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A conserved name or nomen conservandum (plural nomina conservanda, abbreviated as nom. cons.) is a scientific name that has specific nomenclatural protection. That is, the name is retained, even though it violates one or more rules which would otherwise prevent it from being legitimate. Nomen conservandum is a Latin term, meaning "a name to be conserved". The terms are often used interchangeably, such as by the International Code of Nomenclature for Algae, Fungi, and Plants (ICN), while the International Code of Zoological Nomenclature favours the term "conserved name".
The process for conserving botanical names is different from that for zoological names. Under the botanical code, names may also be "suppressed", nomen rejiciendum (plural nomina rejicienda or nomina utique rejicienda, abbreviated as nom. rej.), or rejected in favour of a particular conserved name, and combinations based on a suppressed name are also listed as “nom. rej.”.
Botany
Conservation
In botanical nomenclature, conservation is a nomenclatural procedure governed by Article 14 of the ICN. Its purpose is
"to avoid disadvantageous nomenclatural changes entailed by the strict application of the rules, and especially of the principle of priority [...]" (Art. 14.1).
Conservation is possible only for names at the rank of family, genus or species.
It may effect a change in original spelling, type, or (most commonly) priority.
Conserved spelling (orthographia conservanda, orth. cons.) allows spelling usage to be preserved even if the name was published with another spelling: Euonymus (not Evonymus), Guaiacum (not Guajacum), etc. (see orthographical variant).
Conserved types (typus conservandus, typ. cons.) are often made when it is found that a type in fact belongs to a different taxon from the description, when a name has subsequently been generally misapplied to a different taxon, or when the type belongs to a small group separate from the monophyletic bulk of a taxon.
Conservation of a nam
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https://en.wikipedia.org/wiki/Oryx/Pecos
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Oryx/Pecos is a proprietary operating system developed from scratch by Bell Labs beginning in 1978 for the express purpose of running AT&T's large-scale PBX switching equipment. The operating system was first used with AT&T's flagship System 75, and until very recently, was used in all variations up through and including Definity G3 (Generic 3) switches, now manufactured by AT&T/Lucent Technologies spinoff Avaya. The last system based on Oryx/Pecos was the Avaya G3 CSI running release 13.1 Definity software. The formal end of sale was February 5, 2007. Although widely believed to be a Unix-like variant developed directly by Bell Labs, that is not the case, as it is not based on any version of Unix.
Description
Oryx/Pecos consists of a kernel (Oryx), and the associated processes running on top of it (Pecos). The system is named for Pecos Street, which bounds the Westminster, CO campus of then AT&T's Colorado Bell Labs location, while Oryx was the last word alphabetically before OS in the office dictionary and the Oryx was purportedly the origin of the unicorn myth. The system is loosely based on Thoth (developed at the University of Waterloo) and DEMOS (developed at Los Alamos Scientific Labs).
Features normally found in commercial operating systems are not found in Oryx/Pecos. Such features include:
A documented API structure
Dynamic application execution capability where additional applications can be loaded and executed without a need to compile and link them directly to the operating system
A Disk-Operating System compatible with standard file systems used today
Dynamically-linked libraries
Memory management for strong separation of applications and operating system processes
A commercially available development package
There is one historical link between Oryx/Pecos and Unix: the authors of the above article proposed as a future development the implementation of a UNIX execution environment on top of Oryx/Pecos, and in fact, such a project was underta
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https://en.wikipedia.org/wiki/Beta%20bulge
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A beta bulge can be described as a localized disruption of the regular hydrogen bonding of beta sheet by inserting extra residues into one or both hydrogen bonded β-strands.
Types
β-bulges can be grouped according to their length of the disruption, the number of residues inserted into each strand, whether the disrupted β-strands are parallel or antiparallel and by their dihedral angles (which controls the placement of their side chains). Two types occur commonly. One, the classic beta bulge, occurs within, or at the edge of, antiparallel beta-sheet; the first residue at the outwards bulge typically has the αR, rather than the normal β, conformation.
The other type is the G1 beta bulge, of which there are two common sorts, both mainly occurring in association with antiparallel sheet; one residue has the αL conformation and is usually a glycine. In one sort, the beta bulge loop, one of the hydrogen bonds of the beta-bulge also forms a beta turn or alpha turn, such that the motif is often at the loop of a beta hairpin. In the other sort, the beta link, the beta bulge occurs in combination with, and overlaps, a type II beta turn.
Effects on structure
At the level of the backbone structure, classic β-bulges can cause a simple aneurysm of the β-sheet, e.g., the bulge in the long β-hairpin of ribonuclease A (residues 88–91). A β-bulge can also cause a β-sheet to fold over and cross itself, e.g., when two residues with left-handed and right-handed α-helical dihedral angles are inserted opposite to each other in a β-hairpin, as occurs at Met9 and Asn16 in pseudoazurin (PDB accession code 1PAZ).
Effect on Functionality of Proteins
Conserved bulges regularly affect protein functionality. The most basic function of bulges is to accommodate an extra residue added due to mutation etc., while maintaining the bonding pattern and thus the overall protein architecture. Other bulges are involved with protein binding sites. In specific cases like the Immunoglobulin family proteins
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https://en.wikipedia.org/wiki/Polyproline%20helix
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A polyproline helix is a type of protein secondary structure which occurs in proteins comprising repeating proline residues. A left-handed polyproline II helix (PPII, poly-Pro II, κ-helix) is formed when sequential residues all adopt (φ,ψ) backbone dihedral angles of roughly (-75°, 150°) and have trans isomers of their peptide bonds. This PPII conformation is also common in proteins and polypeptides with other amino acids apart from proline. Similarly, a more compact right-handed polyproline I helix (PPI, poly-Pro I) is formed when sequential residues all adopt (φ,ψ) backbone dihedral angles of roughly (-75°, 160°) and have cis isomers of their peptide bonds. Of the twenty common naturally occurring amino acids, only proline is likely to adopt the cis isomer of the peptide bond, specifically the X-Pro peptide bond; steric and electronic factors heavily favor the trans isomer in most other peptide bonds. However, peptide bonds that replace proline with another N-substituted amino acid (such as sarcosine) are also likely to adopt the cis isomer.
Polyproline II helix
The PPII helix is defined by (φ,ψ) backbone dihedral angles of roughly (-75°, 150°) and trans isomers of the peptide bonds. The rotation angle Ω per residue of any polypeptide helix with trans isomers is given by the equation
Substitution of the poly-Pro II (φ,ψ) dihedral angles into this equation yields almost exactly Ω = -120°, i.e., the PPII helix is a left-handed helix (since Ω is negative) with three residues per turn (360°/120° = 3). The rise per residue is approximately 3.1 Å. This structure is somewhat similar to that adopted in the fibrous protein collagen, which is composed mainly of proline, hydroxyproline, and glycine. PPII helices are specifically bound by SH3 domains; this binding is important for many protein-protein interactions and even for interactions between the domains of a single protein.
The PPII helix is relatively open and has no internal hydrogen bonding, as opposed to the
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https://en.wikipedia.org/wiki/Plasma%20cleaning
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Plasma cleaning is the removal of impurities and contaminants from surfaces through the use of an energetic plasma or dielectric barrier discharge (DBD) plasma created from gaseous species. Gases such as argon and oxygen, as well as mixtures such as air and hydrogen/nitrogen are used. The plasma is created by using high frequency voltages (typically kHz to >MHz) to ionise the low pressure gas (typically around 1/1000 atmospheric pressure), although atmospheric pressure plasmas are now also common.
Methods
In plasma, gas atoms are excited to higher energy states and also ionized. As the atoms and molecules 'relax' to their normal, lower energy states they release a photon of light, this results in the characteristic “glow” or light associated with plasma. Different gases give different colors. For example, oxygen plasma emits a light blue color.
A plasma’s activated species include atoms, molecules, ions, electrons, free radicals, metastables, and photons in the short wave ultraviolet (vacuum UV, or VUV for short) range. This mixture then interacts with any surface placed in the plasma.
If the gas used is oxygen, the plasma is an effective, economical, environmentally safe method for critical cleaning. The VUV energy is very effective in the breaking of most organic bonds (i.e., C–H, C–C, C=C, C–O, and C–N) of surface contaminants. This helps to break apart high molecular weight contaminants. A second cleaning action is carried out by the oxygen species created in the plasma (O2+, O2−, O3, O, O+, O−, ionised ozone, metastable excited oxygen, and free electrons). These species react with organic contaminants to form H2O, CO, CO2, and lower molecular weight hydrocarbons. These compounds have relatively high vapor pressures and are evacuated from the chamber during processing. The resulting surface is ultra-clean. In Fig. 2, a relative content of carbon over material depth is shown before and after cleaning with excited oxygen [1].
If the part consists of easily oxi
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https://en.wikipedia.org/wiki/Sudden%20unexpected%20death%20in%20epilepsy
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Sudden unexpected death in epilepsy (SUDEP) is a fatal complication of epilepsy. It is defined as the sudden and unexpected, non-traumatic and non-drowning death of a person with epilepsy, without a toxicological or anatomical cause of death detected during the post-mortem examination.
While the mechanisms underlying SUDEP are still poorly understood, it is possibly the most common cause of death as a result of complications from epilepsy, accounting for between 7.5 and 17% of all epilepsy-related deaths and 50% of all deaths in refractory epilepsy. The causes of SUDEP seem to be multifactorial and include respiratory, cardiac and cerebral factors as well as the severity of epilepsy and seizures. Proposed pathophysiological mechanisms include seizure-induced cardiac and respiratory arrests.
Among epileptics, SUDEP occurs in about 1 in 1,000 adults and 1 in 4,500 children annually. Rates of death as a result of prolonged seizures (status epilepticus) are not classified as SUDEP.
Categories
The overarching term SUDEP can be subdivided into four different categories: Definite, Probably, Possible, and Unlikely.
Definite SUDEP: a non-traumatic and non-drowning death in an individual with epilepsy, without a cause of death after postmortem examination.
Definite SUDEP Plus: includes the presence of a concomitant condition other than epilepsy, where death may be due to the combined effects of both epilepsy and the other condition.
Probably SUDEP: all the same criteria for Definite SUDEP are met, but no postmortem examination is performed.
Possible SUDEP: insufficient information is available regarding the death, with no postmortem examination.
Unlikely SUDEP: an alternate cause of death has been determined, ruling out the possibility of SUDEP being the cause.
Risk factors
Consistent risk factors include:
Severity of seizures, increased refractoriness of epilepsy and presence of generalized tonic–clonic seizures: the most consistent risk factor is an increased f
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https://en.wikipedia.org/wiki/MSU%20Faculty%20of%20Mechanics%20and%20Mathematics
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The MSU Faculty of Mechanics and Mathematics () is a faculty of Moscow State University.
History
Although lectures in mathematics had been delivered since Moscow State University was founded in 1755, the mathematical and physical department was founded only in 1804. The Mathematics and Mechanics Department was founded on 1 May 1933 and comprised mathematics, mechanics and astronomy departments (the latter passed to the Physics Department in 1956). In 1953 the department moved to a new building on the Sparrow Hills and the current division in mathematics and mechanics branches was settled. In 1970, the Department of Computational Mathematics and Cybernetics broke off the department due to the research in computer science.
A 2014 article entitled "Math as a tool of anti-semitism" in The Mathematics Enthusiast discussed antisemitism in the Moscow State University’s Department of Mathematics during the 1970s and 1980s.
Current state
Today the Department comprises 26 chairs (17 in the mathematical and 9 in the mechanics branch) and 14 research laboratories. Around 350 professors, assistant professors and researchers work at the department. Around 2000 students and 450 postgraduates study at the department. The education lasts 5 years (6 years from 2011).
Notable alumni
Notable faculty (past and present)
Algebra – O. U. Schmidt, A. G. Kurosh, Yu. I. Manin
Number theory – B. N. Delaunay, A. I. Khinchin, L. G. Shnirelman, A. O. Gelfond
Topology – P. S. Alexandrov, A. N. Tychonoff, L. S. Pontryagin, Lev Tumarkin
Real analysis – D. E. Menshov, A. I. Khinchin, N. K. Bari, A. N. Kolmogorov, S. B. Stechkin
Complex analysis – I. I. Privalov, M. A. Lavrentiev, A. O. Gelfond, M. V. Keldysh
Ordinary differential equations – V. V. Stepanov, V. V. Nemitski, V. I. Arnold, N. N. Nekhoroshev
Partial differential equations – I. G. Petrovsky, S. L. Sobolev, E. M. Landis
Mathematical logic and Theory of algorithms – A. A. Markov (Jr.), A. N. Kolmogorov, V. A. Melnikov, V. A. Uspensky
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https://en.wikipedia.org/wiki/Beta%20helix
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A beta helix is a tandem protein repeat structure formed by the association of parallel beta sheet in a helical pattern with either two or three faces. The beta helix is a type of solenoid protein domain. The structure is stabilized by inter-strand hydrogen bonds, protein-protein interactions, and sometimes bound metal ions. Both left- and right-handed beta helices have been identified. These structures are distinct from jelly-roll folds, a different protein structure sometimes known as a "double-stranded beta helix".
The first beta-helix was observed in the enzyme pectate lyase, which contains a seven-turn helix that reaches 34 Å (3.4 nm) long. The P22 phage tail spike protein, a component of the P22 bacteriophage, has 13 turns and in its assembled homotrimer is 200 Å (20 nm) in length. Its interior is close-packed with no central pore and contains both hydrophobic residues and charged residues neutralized by salt bridges.
Both pectate lyase and P22 tailspike protein contain right-handed helices; left-handed versions have been observed in enzymes such as UDP-N-acetylglucosamine acyltransferase and archaeal carbonic anhydrase. Other proteins that contain beta helices include the antifreeze proteins from the beetle Tenebrio molitor (right-handed) and from the spruce budworm, Choristoneura fumiferana (left-handed), where regularly spaced threonines on the β-helices bind to the surface of ice crystals and inhibit their growth.
Beta helices can associate with each other effectively, either face-to-face (mating the faces of their triangular prisms) or end-to-end (forming hydrogen bonds). Hence, β-helices can be used as "tags" to induce other proteins to associate, similar to coiled coil segments.
Members of the pentapeptide repeat family have been shown to possess a quadrilateral beta-helix structure.
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https://en.wikipedia.org/wiki/Jean%20Bartik
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Jean Bartik ( Betty Jean Jennings; December 27, 1924 – March 23, 2011) was one of the original six programmers for the ENIAC computer.
Bartik studied mathematics in school then began work at the University of Pennsylvania, first manually calculating ballistics trajectories and then using ENIAC to do so. The other five ENIAC programmers were Betty Holberton, Ruth Teitelbaum, Kathleen Antonelli, Marlyn Meltzer, and Frances Spence. Bartik and her colleagues developed and codified many of the fundamentals of programming while working on the ENIAC, since it was the first computer of its kind.
After her work on ENIAC, Bartik went on to work on BINAC and UNIVAC, and spent time at a variety of technical companies as a writer, manager, engineer and programmer. She spent her later years as a real estate agent and died in 2011 from congestive heart failure complications.
Content-management framework Drupal's default theme, Bartik, is named in her honor.
Early life and education
Born Betty Jean Jennings in Gentry County, Missouri in 1924, she was the sixth of seven children. Her father, William Smith Jennings (1893–1971) was from Alanthus Grove, where he was a schoolteacher as well as a farmer. Her mother, Lula May Spainhower (1887–1988) was from Alanthus. Jennings had three older brothers, William (January 10, 1915) Robert (March 15, 1918); and Raymond (January 23, 1922); two older sisters, Emma (August 11, 1916) and Lulu (August 22, 1919), and one younger sister, Mable (December 15, 1928).
In her childhood, she would ride on horseback to visit her grandmother, who bought the young girl a newspaper to read every day and became a role model for the rest of her life. She began her education at a local one-room school, and gained local attention for her softball skill. In order to attend high school, she lived with her older sister in the neighboring town, where the school was located, and then began to drive every day despite being only 14. She graduated from Stanberry High
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https://en.wikipedia.org/wiki/AIDA%20%28computing%29
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Abstract Interfaces for Data Analysis (AIDA) is a set of defined interfaces and formats for representing common data analysis objects. The project was instigated and is primarily used by researchers in high-energy particle physics.
History
The goals of the AIDA project were to define abstract interfaces for common physics analysis objects, such as histograms, ntuples (or data trees), fitters, I/O etc. The importance of the interface concept is that a variety of different tools with different implementations can all support a uniform interface: this encourages modular design in data analysis packages and enables users to use their preferred implementation of a certain functionality without having to re-write existing code.
An additional benefit of AIDA is the specification of an XML representation format for data objects, which can be written and read by AIDA-compliant applications. AIDA implementations exist for C++ (OpenScientist), Java (Java Analysis Studio) and Python.
Usage of AIDA interfaces can be found in the Geant4 examples.
As of 2011, the projects seems dormant, with last "recent news" on the project homepage dating from 2005.
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https://en.wikipedia.org/wiki/Buster%20Capp
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Buster Capp is a British comic strip series which debuted on 28 May 1960 in the magazine Buster and ran until January 2000. The character was the mascot of the magazine too. The series is a spin-off of Andy Capp, starring Andy's young son Buster, despite not being drawn by the original artist of that comic, Reg Smythe. The first artist was Bill Titcombe, but Hugh McNeill took over as artist after less than a year. After a few years Àngel Nadal took over and drew the strip until 1974, when he was followed by Reg Parlett. Tom Paterson in turn took over from Parlett in 1985 and drew the strip until 1990. Jimmy Hansen then became the strip's artist until the magazine folded in 2000; the magazine started using reprints of Hansen's earlier strips in 1998, but he still drew a complete new strip once a month, along with covers for every magazine until the end of its life.
Swedish version
There also existed a Swedish version of Buster Capp, done directly for the Swedish edition by local Swedish artists, this version was a heavily sports-orientated humour strip.
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https://en.wikipedia.org/wiki/Double-exchange%20mechanism
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The double-exchange mechanism is a type of a magnetic exchange that may arise between ions in different oxidation states. First proposed by Clarence Zener, this theory predicts the relative ease with which an electron may be exchanged between two species and has important implications for whether materials are ferromagnetic, antiferromagnetic, or exhibit spiral magnetism. For example, consider the 180 degree interaction of Mn-O-Mn in which the Mn "eg" orbitals are directly interacting with the O "2p" orbitals, and one of the Mn ions has more electrons than the other. In the ground state, electrons on each Mn ion are aligned according to the Hund's rule:
If O gives up its spin-up electron to Mn4+, its vacant orbital can then be filled by an electron from Mn3+. At the end of the process, an electron has moved between the neighboring metal ions, retaining its spin. The double-exchange predicts that this electron movement from one species to another will be facilitated more easily if the electrons do not have to change spin direction in order to conform with Hund's rules when on the accepting species. The ability to hop (to delocalize) reduces the kinetic energy. Hence the overall energy saving can lead to ferromagnetic alignment of neighboring ions.
This model is superficially similar to superexchange. However, in superexchange, a ferromagnetic or antiferromagnetic alignment occurs between two atoms with the same valence (number of electrons); while in double-exchange, the interaction occurs only when one atom has an extra electron compared to the other.
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https://en.wikipedia.org/wiki/IntelliTXT
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IntelliTXT is a keyword advertising platform developed by Vibrant Media. Web page publishers insert a script into their pages which calls the IntelliTXT platform when a viewer views the page. This script then finds keywords on the page and double underlines them. When holding the mouse over the double underlined link, an advertisement associated with that word will pop up. Advertisers pay to have their particular words associated to their advertisements.
Customers
According to Vibrant Media, more than 4500 publishers use the IntelliTXT system. Nike, Sony and Microsoft are advertising on the platform, their ads reaching more than 100 million unique users in the US and 170 million internationally each month.
Competitors
Adbrite
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https://en.wikipedia.org/wiki/Margulis%20lemma
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In differential geometry, the Margulis lemma (named after Grigory Margulis) is a result about discrete subgroups of isometries of a non-positively curved Riemannian manifold (e.g. the hyperbolic n-space). Roughly, it states that within a fixed radius, usually called the Margulis constant, the structure of the orbits of such a group cannot be too complicated. More precisely, within this radius around a point all points in its orbit are in fact in the orbit of a nilpotent subgroup (in fact a bounded finite number of such).
The Margulis lemma for manifolds of non-positive curvature
Formal statement
The Margulis lemma can be formulated as follows.
Let be a simply-connected manifold of non-positive bounded sectional curvature. There exist constants with the following property. For any discrete subgroup of the group of isometries of and any , if is the set:
then the subgroup generated by contains a nilpotent subgroup of index less than . Here is the distance induced by the Riemannian metric.
An immediately equivalent statement can be given as follows: for any subset of the isometry group, if it satisfies that:
there exists a such that ;
the group generated by is discrete
then contains a nilpotent subgroup of index .
Margulis constants
The optimal constant in the statement can be made to depend only on the dimension and the lower bound on the curvature; usually it is normalised so that the curvature is between -1 and 0. It is usually called the Margulis constant of the dimension.
One can also consider Margulis constants for specific spaces. For example, there has been an important effort to determine the Margulis constant of the hyperbolic spaces (of constant curvature -1). For example:
the optimal constant for the hyperbolic plane is equal to ;
In general the Margulis constant for the hyperbolic -space is known to satisfy the bounds: for some .
Zassenhaus neighbourhoods
A particularly studied family of examples of negatively curved manifol
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https://en.wikipedia.org/wiki/Pelvetia
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Pelvetia canaliculata, the channelled wrack, is a very common brown alga (Phaeophyceae) found on the rocks of the upper shores of Europe. It is the only species remaining in the monotypic genus Pelvetia. In 1999, the other members of this genus were reclassified as Silvetia due to differences of oogonium structure and of nucleic acid sequences of the rDNA.
Description
Pelvetia grows to a maximum length of in dense tufts, the fronds being deeply channeled on one side: the channels and a mucus layer help prevent the seaweed drying (desiccation) when the tide is out. It is irregularly dichotomously branched with terminal receptacles, and is dark brown in color. Each branch is of uniform width and without a midrib. The receptacles are forked at the tips.
It is distinguished from other large brown algae by the channels along the frond. It has no mid-rib, no air-vesicles and no cryptostomata. It forms the uppermost zone of algae on the shore growing at or above high-water mark. The reproductive organs form swollen, irregularly shaped receptacles at the end of the branches. The conceptacles are hermaphrodite and borne within the receptacles at the apices.
Taxonomy
The genus name of Pelvetia is in honour of François Alexandre Pelvet (1801-1882), who was a French naturalist and plant collector.
The genus was circumscribed by Joseph Decaisne and Gustave Adolphe Thuret in Ann. Sci. Nat. Bot. ser.3, vol.3 on page 12 in 1845.
Reproduction
Both sexes occur in the same plant, the reproductive structures develop at the apices. The receptacles are swollen during the summer and are yellowish-green at maturity.
Ecology
Pelvetia canaliculata is the only large algae growing on rocks forming a zone along the upper shore at the upper littoral zone, on the shores of the British Isles. It tolerates a wide range of exposure conditions. It needs periods of exposure to the air, and sometimes grows so high up a beach that coarse grass and other longshore angiosperms grow among it. If i
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https://en.wikipedia.org/wiki/Automatic%20acoustic%20management
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Automatic acoustic management (AAM) is a method for reducing acoustic emanations in AT Attachment (ATA) mass storage devices for computer data storage, such as ATA hard disk drives and ATAPI optical disc drives. AAM is an optional feature set for ATA/ATAPI devices; when a device supports AAM, the acoustic management parameters are adjustable through a software or firmware user interface.
Details
The ATA/ATAPI sub-command for setting the level of AAM operation is an 8-bit value from 0 to 255. Most modern drives ship with the vendor-defined value of 0x00 in the acoustic management setting. This often translates to the max-performance value of 254 stated in the standard. Values between 128 and 254 (0x80 - 0xFE) enable the feature and select most-quiet to most-performance settings along that range. Though hard drive manufacturers may support the whole range of values, the settings are allowed to be banded, so many values could provide the same acoustic performance.
Although there is no definition of the function implemented to provide acoustic management in the ATA standard, most drives use power control of the head-positioning servo to reduce vibration induced by the head positioning mechanism. Western Digital calls this IntelliSeek™ which uses only enough head acceleration to position the head at the target track and sector "just in time" to access data. Previous seek mechanisms used maximum power and acceleration to position the head. This operation induced the familiar clicking vibration emanating from a seeking hard drive. Western Digital provides a demonstration flash movie illustrating just-in-time head positioning on their web site.
To provide best acoustic performance, some drive manufacturers may limit the maximum seek velocity of the heads for AAM operation. This degrades performance by increasing the average seek time: some head movements are forced to wait an additional disk rotation before accessing data because the head was unable to move to the
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https://en.wikipedia.org/wiki/Emmert%27s%20law
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Emmert's law states that objects that generate retinal images of the same size will look different in physical size (linear size) if they appear to be located at different distances. Specifically, the perceived linear size of an object increases as its perceived distance from the observer increases. This makes intuitive sense: an object of constant size will project progressively smaller retinal images as its distance from the observer increases. Similarly, if the retinal images of two different objects at different distances are the same, the physical size of the object that is farther away must be larger than the one that is closer.
Creation and purpose
Emil Emmert (1844–1911) first described the law in 1881. He noted that an afterimage appeared to increase in size when projected to a greater distance. Some authors thus take Emmert's law to refer strictly to the increase in the apparent size of an after-image when the distance between observer and projection plane is increased, as it did in its original form. Other authors take Emmert's law to apply to any comparative estimation of physical size in which the size of the retinal image, however it may be produced, is equated.
It is unclear whether Emmert intended the increase in distance to refer to an increase in physical distance or an increase in perceived distance, but most authors assume the latter. Under that interpretation, Emmert's law is a special instance of size constancy and of the size–distance invariance hypothesis, which states that the ratio of perceived linear size to perceived distance is a simple function of the visual angle.
The effect of viewing distance on perceived size can be observed by first obtaining an afterimage, which can be achieved by viewing a bright light for a short time, or staring at a figure for a longer time. It appears to grow in size when projected to a further distance. However, the increase in perceived size is much less than would be predicted by geometry, which casts
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https://en.wikipedia.org/wiki/RP-570
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RP-570 is a communications protocol used in industrial environments to communicate between a front-end computer and the substation to be controlled.
It is a SCADA legacy protocol and is based on the low-level protocol IEC TC57, format class 1.2.
RP-570 stands for:
"RTU Protocol based on IEC 57 part 5-1 (present IEC 870) version 0 or 1"
External links
Details may be found here:
RP 570 Protocol Description
Overview of supported protocol features in RP 570
RP 570/1 Master & Slave OPC Server
Network protocols
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https://en.wikipedia.org/wiki/Cold%20vapour%20atomic%20fluorescence%20spectroscopy
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Cold vapour atomic fluorescence spectroscopy (CVAFS) is a subset of the analytical technique known as atomic fluorescence spectroscopy (AFS).
Use for mercury detection
Used in the measurement of trace amounts of volatile heavy metals such as mercury, cold vapour AFS makes use of the unique characteristic of mercury that allows vapour measurement at room temperature. Free mercury atoms in a carrier gas are excited by a collimated ultraviolet light source at a wavelength of 253.7 nanometres. The excited atoms re-radiate their absorbed energy (fluoresce) at this same wavelength. Unlike the directional excitation source, the fluorescence is omnidirectional and may thus be detected using a photomultiplier tube or UV photodiode.
Gold coated traps may be used to collect mercury in ambient air or other media. The traps are then heated, releasing the mercury from the gold while passing argon through the cartridge. This preconcentrates the mercury, increasing sensitivity, and also transfers the mercury into an inert gas.
Transportable analysers
A number of companies have commercialized mercury detection via CVAFS and produced transportable analysers capable of measuring mercury in ambient air. These devices can measure levels in the low parts per quadrillion range (10−15).
EPA-approved methods
Various analytical methods approved by the United States Environmental Protection Agency (EPA) for measuring mercury in wastewater are in common use. EPA Methods 245.7 and 1631 are commonly used for measurement of industrial wastewater using CVAFS.
See also
Other analytical techniques suitable for analyzing heavy metals in air or water:
Inductively coupled plasma mass spectrometry
Atomic absorption spectroscopy
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https://en.wikipedia.org/wiki/SMS%20Magdeburg
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SMS ("His Majesty's Ship ") was a lead ship of the of light cruisers in the German (Imperial Navy). Her class included three other ships: , , and . was built at the AG Weser shipyard in Bremen from 1910 to August 1912, when she was commissioned into the High Seas Fleet. The ship was armed with a main battery of twelve 10.5 cm SK L/45 guns and had a top speed of . was used as a torpedo test ship after her commissioning until the outbreak of World War I in August 1914, when she was brought to active service and deployed to the Baltic.
In the Baltic, fired the first shots of the war against the Russians on 2 August, when she shelled the port of Libau. She participated in a series of bombardments of Russian positions until late August. On the 26th, she participated in a sweep of the entrance to the Gulf of Finland; while steaming off the Estonian coast, she ran aground off the island of Odensholm and could not be freed. A pair of Russian cruisers appeared and seized the ship. Fifteen crew members were killed in the brief engagement. They recovered three intact German code books, one of which they passed to the British. The ability to decrypt German wireless signals provided the British with the ability to ambush German units on several occasions during the war, including the Battle of Jutland. The Russians partially scrapped while she remained grounded before completely destroying the wreck.
Design
was long overall and had a beam of and a draft of forward. She displaced normally and up to at full load. Her propulsion system consisted of three sets of Bergmann steam turbines driving three screw propellers. They were designed to give , but reached in service. These were powered by sixteen coal-fired Marine-type water-tube boilers, although they were later altered to use fuel oil that was sprayed on the coal to increase its burn rate. These gave the ship a top speed of . carried of coal, and an additional of oil that gave her a range of approximately a
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https://en.wikipedia.org/wiki/Modulo-N%20code
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Modulo-N code is a lossy compression algorithm used to compress correlated data sources using modular arithmetic.
Compression
When applied to two nodes in a network whose data are in close range of each other modulo-N code requires one node (say odd) to send the coded data value as the raw data ; the even node is required to send the coded data as the . Hence the name modulo-N code.
Since at least bits are required to represent a number K in binary, the modulo coded data of the two nodes requires bits. As we can generally expect always, because . This is the how compression is achieved.
A compression ratio achieved is
Decompression
At the receiver by joint decoding we may complete the process of extracting the data and rebuilding the original values. The code from the even node is reconstructed by the assumption that it must be close to the data from the odd node. Hence the decoding algorithm retrieves even node data as
The decoder essentially finds the closest match to and the decoded value is declared as
Example
For a mod-8 code, we have
Encoder
D_o=43,D_e=47
M_o=43,M_e=47 mod(8) = 7,
Decoder
M_o=43,M_e=47 mod(8) = 7,
D_o=43,D_e=CLOSEST(43,8⋅k + 7)
D_o=43,D_e=47
Modulo-N decoding is similar to phase unwrapping and has the same limitation: If the difference from one node to the next is more than N/2 (if the phase changes from one sample to the next more than ), then decoding leads to an incorrect value.
See also
DISCUS is a more sophisticated technique for compressing correlated data sources.
Delta encoding is a related algorithm used in lossless compression algorithms designed for correlated data sources.
Information theory
Data compression
Wireless sensor network
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https://en.wikipedia.org/wiki/Malament%E2%80%93Hogarth%20spacetime
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A Malament–Hogarth (M-H) spacetime, named after David B. Malament and Mark Hogarth, is a relativistic spacetime that possesses the following property: there exists a worldline and an event p such that all events along are a finite interval in the past of p, but the proper time along is infinite. The event p is known as an M-H event.
Significance
The significance of M-H spacetimes is that they allow for the implementation of certain non-Turing computable tasks (hypercomputation). The idea is for an observer at some event in p's past to set a computer (Turing machine) to work on some task and then have the Turing machine travel on , computing for all eternity. Since lies in p's past, the Turing machine can signal (a solution) to p at any stage of this never-ending task. Meanwhile, the observer takes a quick trip (finite proper time) through spacetime to p, to pick up the solution. The set-up can be used to decide the halting problem, which is known to be undecidable by an ordinary Turing machine. All the observer needs to do is to prime the Turing machine to signal to p if and only if the Turing machine halts.
Examples
The Kerr metric, which describes empty spacetime around a rotating black hole, possesses these features: a computer can orbit the black hole indefinitely, while an observer falling into the black hole experiences an M-H event as they cross the inner event horizon. (This, however, neglects the effects of black hole evaporation.)
Bibliography
Hogarth, M., 1992, ‘Does General Relativity Allow an Observer to View an Eternity in a Finite Time?’, Foundations of Physics Letters, 5, 173–181.
Hogarth, M., 1994, ‘Non-Turing Computers and Non-Turing Computability’, in D. Hull, M. Forbes, and R. M. Burian (eds), PSA 1994, Vol. 1. East Lansing: Philosophy of Science Association, 126–138.
Hogarth, M., 1996, 'Predictability, Computability and Spacetime', Ph.D. Thesis, University of Cambridge .
Hogarth, M. 2004, ‘Deciding Arithmetic Using SAD Computers’,
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https://en.wikipedia.org/wiki/Princess%20Tomato%20in%20the%20Salad%20Kingdom
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is a video game by Hudson Soft originally released in 1984 for the NEC PC-8801, NEC PC-6001, FM-7 and MSX Japanese home computers.
It was ported on May 27, 1988, to the Famicom, and February 8, 1991 for the Nintendo Entertainment System in North America. It was also released on the Wii's Virtual Console in Japan on January 19, 2010, and in North America on February 8.
The characters are primarily cartoon-like anthropomorphic fruits and vegetables, though the game does contain some human characters, including Princess Tomato's sister, Lisa, and the villainous Farmies.
Plot
Taking the role of Sir Cucumber, a knight, the player is assigned by King Broccoli (now deceased) to defeat the evil Minister Pumpkin, who has kidnapped Princess Tomato. Early on, Sir Cucumber gains a sidekick, Percy the baby persimmon, who offers advice and helps throughout the quest (and always refers to Sir Cucumber as "Boss").
Gameplay
Princess Tomato in the Salad Kingdom plays similarly to a text adventure, though due to the NES's lack of a keyboard accessory, the possible commands are represented by buttons which line both sides of the screen. The commands are fixed and do not change during gameplay. Primarily, the game consists of still screens, with the exception of the "finger wars", mazes and occasional animated character, such as the octoberry and fernbirds. Players can issue commands to the game's protagonist. While the player may run into difficulty determining which actions will advance the game, the only way to "lose" is by failing to defeat the end-game boss, Minister Pumpkin, in a final game of "finger wars".
Legacy
Princess Tomato makes an appearance in Super Bomberman R as a playable DLC character named "Princess Tomato Bomber". She was added in the 2.0 update released in November 2017.
See also
List of Nintendo Entertainment System games
List of Hudson Soft games
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https://en.wikipedia.org/wiki/Command%20language
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A command language is a language for job control in computing. It is a domain-specific and interpreted language; common examples of a command language are shell or batch programming languages.
These languages can be used directly at the command line, but can also automate tasks that would normally be performed manually at the command line. They share this domain—lightweight automation—with scripting languages, though a command language usually has stronger coupling to the underlying operating system. Command languages often have either very simple grammars or syntaxes very close to natural language, to shallow the learning curve, as with many other domain-specific languages.
See also
Command-line interface
In the Beginning... Was the Command Line
Batch processing
Job (computing)
Notes
External links
A longer definition.
Programming language topics
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https://en.wikipedia.org/wiki/Yellow%20hypergiant
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A yellow hypergiant (YHG) is a massive star with an extended atmosphere, a spectral class from A to K, and, starting with an initial mass of about 20–60 solar masses, has lost as much as half that mass. They are amongst the most visually luminous stars, with absolute magnitude (MV) around −9, but also one of the rarest, with just 20 known in the Milky Way and six of those in just a single cluster. They are sometimes referred to as cool hypergiants in comparison with O- and B-type stars, and sometimes as warm hypergiants in comparison with red supergiants.
Classification
The term "hypergiant" was used as early as 1929, but not for the stars currently known as hypergiants. Hypergiants are defined by their '0' luminosity class, and are higher in luminosity than the brightest supergiants of class Ia, although they were not referred to as hypergiants until the late 1970s. Another criterion for hypergiants was also suggested in 1979 for some other highly luminous mass-losing hot stars, but was not applied to cooler stars. In 1991, Rho Cassiopeiae was the first to be described as a yellow hypergiant, likely becoming grouped as a new class of luminous stars during discussions at the Solar physics and astrophysics at interferometric resolution workshop in 1992.
Definitions of the term hypergiant remain vague, and although luminosity class 0 is for hypergiants, they are more commonly designated by the alternative luminosity classes Ia-0 and Ia+. Their great stellar luminosities are determined from various spectral features, which are sensitive to surface gravity, such as Hβ line widths in hot stars or a strong Balmer discontinuity in cooler stars. Lower surface gravity often indicates larger stars, and hence, higher luminosities. In cooler stars, the strength of observed oxygen lines, such as O I at 777.4 nm., can be used to calibrate directly against stellar luminosity.
One astrophysical method used to definitively identify yellow hypergiants is the so-called Keenan
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https://en.wikipedia.org/wiki/Variance%20reduction
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In mathematics, more specifically in the theory of Monte Carlo methods, variance reduction is a procedure used to increase the precision of the estimates obtained for a given simulation or computational effort. Every output random variable from the simulation is associated with a variance which limits the precision of the simulation results. In order to make a simulation statistically efficient, i.e., to obtain a greater precision and smaller confidence intervals for the output random variable of interest, variance reduction techniques can be used.
The main variance reduction methods are
common random numbers
antithetic variates
control variates
importance sampling
stratified sampling
moment matching
conditional Monte Carlo
and quasi random variables (in Quasi-Monte Carlo method)
For simulation with black-box models subset simulation and line sampling can also be used. Under these headings are a variety of specialized techniques; for example, particle transport simulations make extensive use of "weight windows" and "splitting/Russian roulette" techniques, which are a form of importance sampling.
Crude Monte Carlo simulation
Suppose one wants to compute with the random variable defined on the probability space . Monte Carlo does this by sampling i.i.d. copies of
and then to estimate via the sample-mean estimator
Under further mild conditions such as , a central limit theorem will apply such that for large , the distribution of converges to a normal distribution with mean and standard error . Because the standard deviation only converges towards at the rate , implying one needs to increase the number of simulations () by a factor of to halve the standard deviation of , variance reduction methods are often useful for obtaining more precise estimates for without needing very large numbers of simulations.
Common Random Numbers (CRN)
The common random numbers variance reduction technique is a popular and useful variance reduction technique which
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https://en.wikipedia.org/wiki/Carpet%20page
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A carpet page is a full page in an illuminated manuscript containing intricate, non-figurative, patterned designs. They are a characteristic feature of Insular manuscripts, and typically placed at the beginning of a Gospel Book. Carpet pages are characterised by mainly geometrical ornamentation which may include repeated animal forms. They are distinct from pages devoted to highly decorated historiated initials, though the style of decoration may be very similar.
Carpet pages are characterised by ornamentation with brilliant colors, active lines and complex patterns of interlace. They are normally symmetrical, or very nearly so, about both a horizontal and vertical axis, though for example the pictured page from the Lindisfarne Gospels is only symmetrical about a vertical axis. Some art historians find their origin in similar Coptic decorative book pages, and they also clearly borrow from contemporary metalwork decoration. Oriental carpets, or other textiles, may themselves have been influences. The tooled leather book binding of the St Cuthbert Gospel represents a simple carpet page in another medium, and the few surviving treasure bindings – metalwork book covers or book shrines – from the same period, such as that on the Lindau Gospels, are also close parallels. Roman floor mosaics seen in post-Roman Britain, are also cited as a possible source. The Hebrew Codex Cairensis, from 9th century Galilee, also contains a similar type of page, but stylistically very different.
Examples
The earliest surviving example is from the early 7th-century Bobbio Orosius, and relates more closely to Late Antique decoration. There are notable carpet pages in the Book of Kells, the Lindisfarne Gospels, the Book of Durrow, and other manuscripts.
Carpet pages are also found in some medieval Hebrew manuscripts, typically opening the major sections of the book. Islamic manuscripts, especially Qur'ans, often have pages entirely devoted to complex geometrical decoration, but the t
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https://en.wikipedia.org/wiki/Network%20Chemistry
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Network Chemistry was a Wi-Fi security startup based in Redwood City, California. The firm was founded in 2002 by several co-founders including Gary Ramah, Rob Markovich and Dr. Christopher Waters and is backed by venture capital firms such as San Francisco-based Geneva Venture Partners, Innovacom and In-Q-Tel, the investment arm of the CIA.
The company sold products such as RFprotect Distributed, a wireless intrusion detection system; RFprotect Endpoint, a laptop security product; and RFprotect Mobile, a portable tool for analyzing network security. The final product was RFprotect Scanner, a wired-side rogue access point detection and mitigation system utilizing patent-pending device fingerprinting technology.
Network Chemistry also created the Wireless Vulnerabilities and Exploits database, which is the result of a collaborative industry effort to catalog and define exploits and vulnerabilities specifically related to the use of wireless technologies in IT networks.
The wireless security business of Network Chemistry was sold to Aruba Networks (NASDAQ: ARUN) in July 2007.
External links
“Network Chem Gets $6 million” April 2005 article on RedHerring.com
American companies established in 2002
American companies disestablished in 2007
Computer companies established in 2002
Computer companies disestablished in 2007
Defunct computer hardware companies
Defunct computer companies of the United States
Networking hardware companies
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https://en.wikipedia.org/wiki/Word%20error%20rate
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Word error rate (WER) is a common metric of the performance of a speech recognition or machine translation system.
The general difficulty of measuring performance lies in the fact that the recognized word sequence can have a different length from the reference word sequence (supposedly the correct one). The WER is derived from the Levenshtein distance, working at the word level instead of the phoneme level. The WER is a valuable tool for comparing different systems as well as for evaluating improvements within one system. This kind of measurement, however, provides no details on the nature of translation errors and further work is therefore required to identify the main source(s) of error and to focus any research effort.
This problem is solved by first aligning the recognized word sequence with the reference (spoken) word sequence using dynamic string alignment. Examination of this issue is seen through a theory called the power law that states the correlation between perplexity and word error rate.
Word error rate can then be computed as:
where
S is the number of substitutions,
D is the number of deletions,
I is the number of insertions,
C is the number of correct words,
N is the number of words in the reference (N=S+D+C)
The intuition behind 'deletion' and 'insertion' is how to get from the reference to the hypothesis. So if we have the reference "This is wikipedia" and hypothesis "This _ wikipedia", we call it a deletion.
When reporting the performance of a speech recognition system, sometimes word accuracy (WAcc) is used instead:
Note that since N is the number of words in the reference, the word error rate can be larger than 1.0, and thus, the word accuracy can be smaller than 0.0.
Experiments
It is commonly believed that a lower word error rate shows superior accuracy in recognition of speech, compared with a higher word error rate. However, at least one study has shown that this may not be true. In a Microsoft Research experiment, it was shown
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https://en.wikipedia.org/wiki/Aladdin%20Knowledge%20Systems
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Aladdin Knowledge Systems (formerly and ) was a company that produced software for digital rights management and Internet security. The company was acquired by Safenet Inc, in 2009. Its corporate headquarters are located in Belcamp, MD.
History
Aladdin Knowledge Systems was founded in 1985 by Jacob (Yanki) Margalit, when he was 23 years old; he was soon joined by his brother Danny Margalit, who took the responsibility for product development at the age of 18, while at the same time completing a Mathematics and Computer Science degree at Tel Aviv University. In its early years the company developed two product lines, an artificial intelligence package (which was dropped early on) and a hardware product to prevent unauthorized software copying, similar to digital rights management. Margalit raised just $10,000 as an initial capital for the company.
The digital rights management product became a success and by 1993 generated sales of $4,000,000. The same year that company had an initial public offering on NASDAQ raising $7,900,000. In 2004 the company's shares were also listed on the Tel Aviv Stock Exchange. By 2007 the company's annual revenues reached over $105 million.
In mid-2008, Vector Capital was attempting to purchase Aladdin. Vector initially offered $14.50 per share, but Aladdin's founder Margalit refused the offer arguing that the company was worth more. Aladdin's shareholders agreed on the merger in February 2009 at $11.50 per share, in cash. In March 2009, Vector Capital acquired Aladdin and officially merged it with SafeNet.
Corporate timeline
1985 – Aladdin Knowledge Systems was established
1993 – Aladdin held an initial public offering
1996 – Aladdin acquired the German company FAST
1998 – Aladdin patented USB smart card-based authentication tokens
1998_Dec – Aladdin acquired the software protection business of EliaShim
1999 – Aladdin acquired the eSafe "content security" business of EliaShim
2000 – Aladdin acquired 10% of Comsec
2001 –
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https://en.wikipedia.org/wiki/Microtron
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A microtron is a type of particle accelerator concept originating from the cyclotron in which the accelerating field is not applied through large D-shaped electrodes, but through a linear accelerator structure. The classic microtron was invented by Vladimir Veksler around 1944.
The kinetic energy of the particles is increased by a constant amount per field change (one half or a whole revolution). Microtrons are designed to operate at constant field frequency and magnetic field in the ultrarelativistic limit. Thus they are especially suited for very light elementary particles, namely electrons.
In a microtron, due to the electrons' increasing momentum, the particle paths are different for each pass. The time needed for that is proportional to the pass number. The slow electrons need one electric field oscillation, the faster electrons need an integer multiple of this oscillation.
Racetrack microtron
A racetrack microtron is a larger-scale microtron which uses two electromagnets instead of one. Both electromagnets supply a homogeneous magnetic field in a half-circle formed region, and the particles path between both magnets is thus straight. One advantage of this is that the accelerator cavity can be larger, enabling the use of different linear accelerator (linac) forms, and is not installed in a region with large magnetic fields.
The linac is placed near the edge of the gap between the dee-shaped magnets. The remainder of the gap is used for focusing devices. The electron is readmitted to the linac after each revolution. This procedure can be repeated until the increasing radius of the particle's path makes further acceleration impossible. The particle beam is then deflected into an experiment area or a further accelerator stage.
The world's largest racetrack-microtron is the Mainz Microtron.
Applications
Microtrons provide high-energy electron beams with a low beam emittance (no radiation equilibrium) and a high repetition rate (equal to the operation frequen
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https://en.wikipedia.org/wiki/StICQ
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stICQ is an ICQ client for mobile phones with symbian OS.
StICQ was written by the Russian programmer Sergey Taldykin. StICQ is a native Symbian application (.SIS) for instant messaging over Internet for the ICQ network (using the OSCAR protocol).
It supports all main statuses including "Not Available", "Invisible" etc., contact search using ICQ UID, black lists, multi-user support, sound announcements and even SMS sending using default ICQ server.
Its features are its small size, low memory usage and relatively stable work. One of the key features of the client is its ability to suspend outcoming data until GPRS coverage is available. It also suspend the status of the user, while all other mobile clients usually report connection problem and drop the user out.
Currently, stICQ does not support smiley pictures but have a unique feature of quick emoticon input using the call button (special plugin required).
Notable, stICQ supports the yellow "Ready to chat" extended status while "Depressive", as well as "At home", "At work" etc. are displayed as "Offline". This caused to call stICQ an "anti-depressive ICQ".
The source code has been sold to the development team of Quiet Internet Pager messenger. 1.01 version QiP for Symbian has been released recently.
StICQ is free for download, as are a wide variety of mods changing status icons and menu text.
Keypad shortcuts
Pressing asterisk in a contact list window allows you to maximize the program window. It will also affect message windows.
Pressing the green button allows the smiley templates to be inserted by downloading and installing the templates file (stICQ.tpl).
Known bugs
StICQ is known to drop out when receiving large amounts of text in one message. Thus, users should beware their interlocutor of sending messages that exceeds 10-15 phone display lines.
When using StICQ with a T9 dictionary, users should press any cursor key to get rid of "Previous" command for right button after sending a message or the
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https://en.wikipedia.org/wiki/Platensimycin
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Platensimycin, a metabolite of Streptomyces platensis, is an antibiotic, which act by blocking enzymes (β-ketoacyl-(acyl-carrier-protein (ACP)) synthase I/II (FabF/B)).
History
Platensimycin was first isolated from a strain of Streptomyces platensis by workers at Merck. Screens of 250,000 natural product extracts (83,000 strains in three growth conditions) led to the identification of a potent and selective small molecule from a strain of Streptomyces platensis recovered from a soil sample collected in South Africa. The identification process was carried out using a two-plate system in which control organisms were compared to cells expressing FabF antisense RNA. This method uses a combination of target-based whole-cell and biochemical assays, allowing compounds to be detected at concentrations that would be too low to detect using whole cell assays. The molecule they identified, platensimycin (C24H27NO7, relative molecular mass 441.47), comprises two distinct structural elements connected by an amide bond. The Merck Group showed that platensimycin has potent, broad-spectrum Gram-positive activity in vitro and exhibits no cross-resistance to other key antibiotic-resistant bacteria including Methicillin-resistant Staphylococcus aureus(MRSA), vancomycin-intermediate S. aureus, vancomycin-resistant Enterococci, and linezolid-resistant and macrolide-resistant pathogens.
As confirmed by total synthesis of racemic platensimycin, its structure consists of a 3-amino-2,4-dihydroxybenzoic acid polar part linked through an amide bond to a lipophilic tetracyclic ketolide.
Clinical use
Platensimycin is an experimental drug in preclinical trials involving MRSA in a mouse model. Platensimycin is an effective antibiotic in vivo when continuously administered to cells. Efficacy is reduced when administered by more conventional means. Clinical trials have been delayed. A variety of modifications have been investigated. and increase the activity of platensimycin.
Biosynthesis
Bi
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https://en.wikipedia.org/wiki/Glycosyltransferase
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Glycosyltransferases (GTFs, Gtfs) are enzymes (EC 2.4) that establish natural glycosidic linkages. They catalyze the transfer of saccharide moieties from an activated nucleotide sugar (also known as the "glycosyl donor") to a nucleophilic glycosyl acceptor molecule, the nucleophile of which can be oxygen- carbon-, nitrogen-, or sulfur-based.
The result of glycosyl transfer can be a carbohydrate, glycoside, oligosaccharide, or a polysaccharide. Some glycosyltransferases catalyse transfer to inorganic phosphate or water. Glycosyl transfer can also occur to protein residues, usually to tyrosine, serine, or threonine to give O-linked glycoproteins, or to asparagine to give N-linked glycoproteins. Mannosyl groups may be transferred to tryptophan to generate C-mannosyl tryptophan, which is relatively abundant in eukaryotes. Transferases may also use lipids as an acceptor, forming glycolipids, and even use lipid-linked sugar phosphate donors, such as dolichol phosphates in eukaryotic organism, or undecaprenyl phosphate in bacteria.
Glycosyltransferases that use sugar nucleotide donors are Leloir enzymes, after Luis F. Leloir, the scientist who discovered the first sugar nucleotide and who received the 1970 Nobel Prize in Chemistry for his work on carbohydrate metabolism. Glycosyltransferases that use non-nucleotide donors such as dolichol or polyprenol pyrophosphate are non-Leloir glycosyltransferases.
Mammals use only 9 sugar nucleotide donors for glycosyltransferases: UDP-glucose, UDP-galactose, UDP-GlcNAc, UDP-GalNAc, UDP-xylose, UDP-glucuronic acid, GDP-mannose, GDP-fucose, and CMP-sialic acid. The phosphate(s) of these donor molecules are usually coordinated by divalent cations such as manganese, however metal independent enzymes exist.
Many glycosyltransferases are single-pass transmembrane proteins, and they are usually anchored to membranes of Golgi apparatus
Mechanism
Glycosyltransferases can be segregated into "retaining" or "inverting" enzymes according to
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https://en.wikipedia.org/wiki/List%20of%20food%20additives
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Food additives are substances added to food to preserve flavor or enhance its taste, appearance, or other qualities.
Purposes
Additives are used for many purposes but the main uses are:
Acids Food acids are added to make flavors "sharper", and also act as preservatives and antioxidants. Common food acids include vinegar, citric acid, tartaric acid, malic acid, folic acid, fumaric acid, and lactic acid.
Acidity regulators Acidity regulators are used to change or otherwise control the acidity and alkalinity of foods.
Anticaking agents Anticaking agents keep powders such as milk powder from caking or sticking.
Antifoaming agents Antifoaming agents reduce or prevent foaming in foods.
Antioxidants Antioxidants such as vitamin C act as preservatives by inhibiting the effects of oxygen on food, and can be beneficial to health.
Bulking agents Bulking agents such as starch are additives that increase the bulk of a food without affecting its nutritional value.
Food coloring Colorings are added to food to replace colors lost during preparation, or to make food look more attractive.
Color retention agents In contrast to colorings, color retention agents are used to preserve a food's existing color.
Emulsifiers Emulsifiers allow water and oils to remain mixed together in an emulsion, as in mayonnaise, ice cream, and homogenized milk.
Flavors Flavors are additives that give food a particular taste or smell, and may be derived from natural ingredients or created artificially.
Flavor enhancers Flavor enhancers enhance a food's existing flavors. They may be extracted from natural sources (through distillation, solvent extraction, maceration, among other methods) or created artificially.
Flour treatment agents Flour treatment agents are added to flour to improve its color or its use in baking.
Glazing agents Glazing agents provide a shiny appearance or protective coating to foods.
Humectants Humectants prevent foods from drying out.
Tracer gas Tracer gas allow for pac
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https://en.wikipedia.org/wiki/QMC%40Home
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QMC@Home was a volunteer computing project for the BOINC client aimed at further developing and testing Quantum Monte Carlo (QMC) for use in quantum chemistry. It is hosted by the University of Münster with participation by the Cavendish Laboratory. QMC@Home allows volunteers from around the world to donate idle computer cycles to help calculate molecular geometry using Diffusion Monte Carlo.
The project is developing a new application using density functional theory.
The project began its Beta testing on 23 May 2006. , QMC@Home has about 7,500 active participants from 102 countries, contributing about 5 teraFLOPS of computation power.
Workunits
In order to get results from home computers the work is split into "workunits". The time it takes to complete a workunit depends on the size of the calculated system and the speed of the user's computer. The target time is between 4 and 48 hours on a 2.4 GHz system.
This is a list of molecules recently tested:
1a Ammonia; 1 Ammonia dimer; 2a Water; 2 Water dimer; 3a Formic acid; 3 Formic acid dimer; 4a Formamide; 4 Formamide dimer; 5a Uracil; 5 Uracil dimer; 6a 2-pyridoxine; 6b 2-aminopyridine; 6 2-pyridoxine/2-aminopyridine; 7a Adenine; 7b Thymine; 7 Adenine/thymine WC; 8a Methane; 8 Methane dimer; 9a Ethene; 9 Ethene dimer; 10 Benzene/methane; 11a Benzene; 11 Benzene dimer; 12a Pyrazine; 12 Pyrazine dimer; 13 Uracil dimer; 14a Indole; 14 Indole/benzene; 15 Adenine/thymine stack; 16b Ethyne; 16 Ethene/ethyne; 17 Benzene/water; 18 Benzene/ammonia; 19b Hydrogen cyanide; 19 Benzene/hydrogen cyanide; 20 Benzene dimer; 21 Indole/benzene; 22a Phenol; 22 Phenol dimer
See also
List of volunteer computing projects
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https://en.wikipedia.org/wiki/Web%20Services%20Conversation%20Language
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The Web Service Conversation Language (WSCL) proposal defines the overall input and output message sequences for one web service using a finite state automaton FSA over the alphabet of message types.
External links
Web Service Conversation Language (WSCL) proposal
Web service specifications
World Wide Web Consortium standards
XML-based standards
Web services
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https://en.wikipedia.org/wiki/Passive%20acoustics
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Passive acoustics is the action of listening for sounds, often at specific frequencies or for purposes of specific analyses. It is often used for passive acoustic monitoring (PAM), the act of recording animal and environmental sounds through the use of acoustic sensors for the purpose of tracking animals and answering other ecological questions.
PAM has risen as a valuable method for a variety of queries relating to conservation, applied and behavioral ecology, and biodiversity. There are a variety of tools and machinery available for monitoring in both terrestrial and aquatic environments. This method of ecological monitoring is especially valuable for species that vocalize and are hard to observe visually. Passive acoustic monitoring also allows for observation across spatial and temporal scales previously unseen due to the limitations of data collection.
As applied to underwater acoustics, also termed hydroacoustics, passive acoustics can be used to listen for underwater explosions, earthquakes, volcanic eruptions, sounds produced by fish and other marine animals, vessel activity or aquatic detecting equipment (as in hydroacoustics to track fish).
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https://en.wikipedia.org/wiki/MySociety
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mySociety is a UK-based registered charity, previously named UK Citizens Online Democracy. It began as a UK-focused organisation with the aim of making online democracy tools for UK citizens. However, those tools were open source, so that the code could be (and soon was) redeployed in other countries.
mySociety went on to simplify and internationalise its code and through the now dormant Poplus project, encouraged others to share open source code that would minimise the amount of duplication in civic tech coding.
Like many non-profits, mySociety sustains itself with a mixture of grant funding and commercial work, providing software and development services to local government and other organisations.
mySociety was founded by Tom Steinberg in September 2003, and started activity after receiving a £250,000 grant in September 2004. Steinberg says that it was inspired by a collaboration with his then-flatmate James Crabtree which spawned Crabtree's article "Civic hacking: a new agenda for e-democracy".
In March 2015, Steinberg announced his decision to stand down as executive director of mySociety. In July of that year, Mark Cridge became the organisation's new CEO.
Projects
TheyWorkForYou is a parliamentary monitoring website which aims to make it easier for UK citizens to understand what is going on in Westminster as well as Scottish Parliament, the Welsh Assembly and the Northern Ireland Assembly. It also helps create accountability for UK politicians by publishing a complete archive of every word spoken in Parliament, along with a voting record and other details for each MP, past and present.
FixMyStreet platform is free and open source software which enables anyone to run a map based website and app that helps people inform their local authority of problems needing their attention, such as potholes, broken streetlamps, etc. The UK version is FixMyStreet.com. mySociety also provide FixMyStreet as a report making system for several local and transport authorit
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https://en.wikipedia.org/wiki/Lyceum%20TV
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The RCA Lyceum TV was a commercial monitor/receiver with a large input/output panel on the back, and a long grounded plug. During the mid-80s, RCA released the Colortrak 2000, a television identical to the Dimensia table-top model. Even though the Colortrak was considered the mid-range model, those bearing the name Colortrak 2000, were considered high-end, along with the Dimensia. The Lyceum TV, Dimensia, and Colortrak 2000 models all basically had the same chassis (a wood grain veneer, or black laminate for some Dimensias, and fabric covered speakers on the sides of the cabinet).
Many Colortrak 2000, Lyceum, and Dimensia TVs came packaged with a very large remote control, the Digital Command Center. There are several different versions of the Digital Command Center, but a main feature was that it could control an array of selected RCA components, all with the one remote – a universal remote only for RCA products, so to speak. The Dimensia version of the remote was called the "Dimensia-Intelligent Audio Video" and had identical buttons to the Digital Command Center.
See also
RCA Dimensia
Colortrak 2000
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https://en.wikipedia.org/wiki/Kasha%27s%20rule
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Kasha's rule is a principle in the photochemistry of electronically excited molecules. The rule states that photon emission (fluorescence or phosphorescence) occurs in appreciable yield only from the lowest excited state of a given multiplicity. It is named after American spectroscopist Michael Kasha, who proposed it in 1950.
Description and explanation
The rule is relevant in understanding the emission spectrum of an excited molecule. Upon absorbing a photon, a molecule in its electronic ground state (denoted S0, assuming a singlet state) may – depending on the photon wavelength – be excited to any of a set of higher electronic states (denoted Sn where n>0). However, according to Kasha's rule, photon emission (termed fluorescence in the case of an S state) is expected in appreciable yield only from the lowest excited state, S1. Since only one state is expected to yield emission, an equivalent statement of the rule is that the emission wavelength is independent of the excitation wavelength.
The rule can be explained by the Franck–Condon factors for vibronic transitions. For a given pair of energy levels that differ in both vibrational and electronic quantum numbers, the Franck–Condon factor expresses the degree of overlap between their vibrational wavefunctions. The greater the overlap, the more quickly the molecule can undergo a transition from the higher to the lower level. Overlap between pairs is greatest when the two vibrational levels are close in energy; this tends to be the case when the vibrationless levels of the electronic states coupled by the transition (where the vibrational quantum number v is zero) are close. In most molecules, the vibrationless levels of the excited states all lie close together, so molecules in upper states quickly reach the lowest excited state, S1, before they have time to fluoresce. However, the energy gap between S1 and S0 is greater, so here fluorescence occurs, since it is now kinetically competitive with internal convers
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https://en.wikipedia.org/wiki/Anterior%20external%20arcuate%20fibers
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The anterior external arcuate fibers (ventral external arcuate fibers) vary as to their prominence: in some cases they form an almost continuous layer covering the medullary pyramids and olivary body, while in other cases they are barely visible on the surface.
Most of them reach the surface by way of the anterior median fissure, and arch backward over the pyramid.
Reinforced by others which emerge between the pyramid and olive, they pass backward over the olive and lateral district of the medulla oblongata, and enter the inferior peduncle.
As the fibers arch across the pyramid, they enclose a small nucleus which lies in front of and medial to the pyramid.
This is named the arcuate nucleus, and is serially continuous above with the pontine nuclei in the pons; it contains small fusiform (spindle-shaped) cells, around which some of the arcuate fibers end, and from which others arise.
Additional images
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https://en.wikipedia.org/wiki/Exception%20safety
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Exception safety is the state of code working correctly when exceptions are thrown. To aid in ensuring exception safety, C++ standard library developers have devised a set of exception safety levels, contractual guarantees of the behavior of a data structure's operations with regards to exceptions. Library implementers and clients can use these guarantees when reasoning about exception handling correctness. The exception safety levels apply equally to other languages and error-handling mechanisms.
History
As David Abrahams writes, "nobody ever spoke of 'error-safety' before C++ had exceptions." The term appeared as the topic of publications in JTC1/SC22/WG21, the C++ standard committee, as early as 1994. Exception safety for the C++ standard library was first formalized for STLport by Abrahams, establishing the basic safety/strong safety distinction. This was extended to the modern basic/strong/nothrow guarantees in a later proposal.
Background
Exceptions provide a form of non-local control flow, in that an exception may "bubble up" from a called function. This bubbling can cause an exception safety bug by breaking invariants of a mutable data structure, as follows:
A step of an operation on a mutable data structure modifies the data and breaks an invariant.
An exception is thrown and control "bubbles up", skipping the rest of the operation's code that would restore the invariant
The exception is caught and recovered from, or a finally block is entered
The data structure with broken invariant is used by code that assumes the invariant, resulting in a bug
Code with a bug such as the above can be said to be "exception unsafe".
Classification
The C++ standard library provides several levels of exception safety (in decreasing order of safety):
No-throw guarantee, also known as failure transparency: Operations are guaranteed to succeed and satisfy all requirements even in exceptional situations. If an exception occurs, it will be handled internally and n
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https://en.wikipedia.org/wiki/Ergun%20equation
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The Ergun equation, derived by the Turkish chemical engineer Sabri Ergun in 1952, expresses the friction factor in a packed column as a function of the modified Reynolds number.
Equation
where and are defined as
and
where:
is the modified Reynolds number,
is the packed bed friction factor
is the pressure drop across the bed,
is the length of the bed (not the column),
is the equivalent spherical diameter of the packing,
is the density of fluid,
is the dynamic viscosity of the fluid,
is the superficial velocity (i.e. the velocity that the fluid would have through the empty tube at the same volumetric flow rate)
is the void fraction (porosity) of the bed.
is the particle Reynolds Number (based on superficial velocity)
.
Extension
To calculate the pressure drop in a given reactor, the following equation may be deduced
This arrangement of the Ergun equation makes clear its close relationship to the simpler Kozeny-Carman equation which describes laminar flow of fluids across packed beds via the first term on the right hand side. On the continuum level, the second order velocity term demonstrates that the Ergun equation also includes the pressure drop due to inertia, as described by the Darcy–Forchheimer equation.
The extension of the Ergun equation to fluidized beds, where the solid particles flow with the fluid, is discussed by Akgiray and Saatçı (2001).
See also
Hagen–Poiseuille equation
Kozeny–Carman equation
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https://en.wikipedia.org/wiki/Potentially%20Hazardous%20Food
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Potentially Hazardous Food is a term used by food safety organizations to classify foods that require time-temperature control to keep them safe for human consumption. A PHF is a food that:
Contains moisture – usually regarded as a water activity greater than 0.85
Contains protein
Is neutral to slightly acidic – typically having a pH between 4.6 and 7.5
US FDA Definition
Potentially Hazardous Food has been redefined by the US Food and Drug Administration in the 2013 FDA Food Code to Time/Temperature Control for Safety Food. Pages 22 and 23 (pdf pages 54 and 55), state the following:
"Time/temperature control for safety food" means a FOOD that requires time/temperature control for safety (TCS) to limit pathogenic microorganism growth or toxin formation.
"Time/temperature control for safety food" includes:
An animal FOOD that is raw or heat-treated; a plant FOOD that is heat-treated or consists of raw seed sprouts, cut melons, cut leafy greens, cut tomatoes or mixtures of cut tomatoes that are not modified in a way so that they are unable to support pathogenic microorganism growth or toxin formation, or garlic-in-oil mixtures that are not modified in a way so that they are unable to support pathogenic microorganism growth or toxin formation; and
Except as specified in Subparagraph (3)(d) of this definition, a FOOD that because of the interaction of its AW and pH values is designated as Product Assessment Required (PA) in Table A or B of this definition:
"Time/temperature control for safety food" does not include:
An air-cooled hard-boiled EGG with shell intact, or an EGG with shell intact that is not hard-boiled, but has been pasteurized to destroy all viable salmonellae;
A FOOD in an unopened HERMETICALLY SEALED CONTAINER that is commercially processed to achieve and maintain commercial sterility under conditions of non-refrigerated storage and distribution;
A FOOD that because of its pH or AW value, or interaction of AW and pH values, is designated as a
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https://en.wikipedia.org/wiki/Thyroxine%205-deiodinase
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Thyroxine 5-deiodinase also known as type III iodothyronine deiodinase (EC number 1.21.99.3) is an enzyme that in humans is encoded by the DIO3 gene. This enzyme catalyses the following chemical reaction
3,3',5'-triiodo-L-thyronine + iodide + A + H+ L-thyroxine + AH2
The protein encoded by this intronless gene belongs to the iodothyronine deiodinase family. It catalyzes the inactivation of thyroid hormone by inner ring deiodination of the prohormone thyroxine (T4) and the bioactive hormone 3,3',5-triiodothyronine (T3) to inactive metabolites, 3,3',5'-triiodothyronine (RT3) and 3,3'-diiodothyronine (T2), respectively. This enzyme is highly expressed in the pregnant uterus, placenta, fetal and neonatal tissues, suggesting that it plays an essential role in the regulation of thyroid hormone inactivation during embryological development.
Discovery
The gene was mapped to chromosome 14q32 using fluorescence in situ hybridization (FISH) in 1998.
Structure
This protein contains a selenocysteine (Sec) residue, which is essential for efficient enzyme activity. The selenocysteine is encoded by the UGA codon, which normally signals translation termination. The 3' UTR of Sec-containing genes have a common stem-loop structure, the sec insertion sequence (SECIS), which is necessary for the recognition of UGA as a Sec codon rather than as a stop signal.
Function
The DIO3 gene codes for type 3 iodothyronine deiodinase (D3), an enzyme that inactivates thyroid hormones and is highly expressed throughout fetal development, peaking early and decreasing towards the end of gestation. Part of the DLK1-Dio3 imprinting control region, this gene is one involved in the epigenetic process that causes a subset of genes to be regulated based on their parental origin . Such imprinted genes are required for the formation of the placenta as well as the development of cellular lineages such as those derived from the mesoderm and ectoderm. D3 is found in the pregnant uterus, placenta,
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https://en.wikipedia.org/wiki/Rovibronic%20coupling
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Rovibronic coupling, also known as rotation/vibration-electron coupling, denotes the simultaneous interactions between rotational, vibrational, and electronic degrees of freedom in a molecule. When a rovibronic transition occurs, the rotational, vibrational, and electronic states change simultaneously, unlike in rovibrational coupling. The coupling can be observed spectroscopically and is most easily seen in the Renner–Teller effect in which a linear polyatomic molecule is in a degenerate electronic state and bending vibrations will cause a large rovibronic coupling.
See also
Afterglow plasma
Vibronic coupling
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https://en.wikipedia.org/wiki/Test%20CD
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A test CD is a compact disc containing tracks of musical and technical tests and demonstrations. Most of the tracks are made of electronic signals and pure frequencies. The purpose of these specialized compact discs is to make accurate tests and calibrate audio equipment.
Releases
A wide variety of CD-DA test discs have been produced in the past, and a few are still in production:
Stereophile Test CD 2
CD-CHECK Test Disc
NAB Broadcast & Audio Test CD, Vol 1 (still in production)
NAB Broadcast & Audio Test CD, Vol 2 (still in production)
Precision Test Signals
The Ultimate Test CD
CBS Records CD-1 Standard Test Disc (with EIA standard signals)
EIAJ CD-1 Standard Test Disc (YGDS 13) (EIAJ Standard CP-308)
Denon Audio Technical CD 38C39-7147
Japan Audio Society Audio Test CD-1 (YDDS-2)
Philips Test Sample 4a
Sony Test CD Type 3 YEDS-7
Technics CD Test Disc SH-CD001
See also
Audio equipment testing
Super Audio CD
|
https://en.wikipedia.org/wiki/Efficient%20coding%20hypothesis
|
The efficient coding hypothesis was proposed by Horace Barlow in 1961 as a theoretical model of sensory coding in the brain. Within the brain, neurons communicate with one another by sending electrical impulses referred to as action potentials or spikes. One goal of sensory neuroscience is to decipher the meaning of these spikes in order to understand how the brain represents and processes information about the outside world. Barlow hypothesized that the spikes in the sensory system formed a neural code for efficiently representing sensory information. By efficient Barlow meant that the code minimized the number of spikes needed to transmit a given signal. This is somewhat analogous to transmitting information across the internet, where different file formats can be used to transmit a given image. Different file formats require different number of bits for representing the same image at given distortion level, and some are better suited for representing certain classes of images than others. According to this model, the brain is thought to use a code which is suited for representing visual and audio information representative of an organism's natural environment .
Efficient coding and information theory
The development of the Barlow's hypothesis was influenced by information theory introduced by Claude Shannon only a decade before. Information theory provides the mathematical framework for analyzing communication systems. It formally defines concepts such as information, channel capacity, and redundancy. Barlow's model treats the sensory pathway as a communication channel where neuronal spiking is an efficient code for representing sensory signals. The spiking code aims to maximize available channel capacity by minimizing the redundancy between representational units. H. Barlow was not the very first one to introduce the idea: it already appears in a 1954 article written by F. Attneave.
A key prediction of the efficient coding hypothesis is that sensory
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https://en.wikipedia.org/wiki/Pi%20helix
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A pi helix (or π-helix) is a type of secondary structure found in proteins. Discovered by crystallographer Barbara Low in 1952 and once thought to be rare, short π-helices are found in 15% of known protein structures and are believed to be an evolutionary adaptation derived by the insertion of a single amino acid into an α-helix. Because such insertions are highly destabilizing, the formation of π-helices would tend to be selected against unless it provided some functional advantage to the protein. π-helices therefore are typically found near functional sites of proteins.
Standard structure
The amino acids in a standard π-helix are arranged in a right-handed helical structure. Each amino acid corresponds to an 87° turn in the helix (i.e., the helix has 4.1 residues per turn), and a translation of along the helical axis. Most importantly, the N-H group of an amino acid forms a hydrogen bond with the C=O group of the amino acid five residues earlier; this repeated i + 5 → i hydrogen bonding defines a π-helix. Similar structures include the 310 helix (i + 3 → i hydrogen bonding) and the α-helix (i + 4 → i hydrogen bonding).
The majority of π-helices are only 7 residues in length and do not adopt regularly repeating (φ, ψ) dihedral angles throughout the entire structure like that of α-helices or β-sheets. Because of this, textbooks that provide single dihedral values for all residues in the π-helix are misleading. Some generalizations can be made, however. When the first and last residue pairs are excluded, dihedral angles exist such that the ψ dihedral angle of one residue and the φ dihedral angle of the next residue sum to roughly −125°. The first and last residue pairs sum to −95° and −105°, respectively. For comparison, the sum of the dihedral angles for a 310 helix is roughly −75°, whereas that for the α-helix is roughly −105°. Proline is often seen immediately following the end of π-helices. The general formula for the rotation angle Ω per residue of an
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https://en.wikipedia.org/wiki/Ruth%20Teitelbaum
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Ruth Teitelbaum ( Lichterman; February 1, 1924 – August 9, 1986) was one of the first computer programmers in the world. Teitelbaum was one of the original programmers for the ENIAC computer.
The other five ENIAC programmers were Jean Bartik, Betty Holberton, Kathleen Antonelli, Marlyn Meltzer, and Frances Spence.
Early life and education
Teitelbaum was born Ruth Lichterman in The Bronx, New York, on February 1, 1924. She was the elder of two children, and the only daughter, of Sarah and Simon Lichterman, a teacher. Her parents were Jewish immigrants from Russia. She graduated from Hunter College with a B.Sc. in Mathematics.
Career
Teitelbaum was hired by the Moore School of Electrical Engineering at the University of Pennsylvania to compute ballistics trajectories. The Moore School was funded by the US Army during the Second World War. Here a group of about 80 women worked manually calculating ballistic trajectories - complex differential calculations.
In June 1943, the Army decided to fund an experimental project - the first all-electronic digital computer called the Electronic Numerical Integrator and Computer (ENIAC). The computer was a huge machine with 40 black 8-foot panels. The programmers had to physically program it using 3000 switches, and telephone switching cords in a dozen trays, to route the data, and the program, through the machine. This is the reason why these women were called "computers".
Along with Marlyn Meltzer, Teitelbaum was part of a special area of the ENIAC project to calculate ballistic trajectory equations using analog technology. They taught themselves and others certain functions of the ENIAC and helped prepare the ballistics software. In 1946, the ENIAC computer was unveiled before the public and the press. The seven women were the only generation of programmers to program the ENIAC.
After the war, Teitelbaum traveled with ENIAC to the Ballistics Research Laboratory at the Aberdeen Proving Ground where she remained for two mo
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https://en.wikipedia.org/wiki/310%20helix
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{{DISPLAYTITLE:310 helix}}
A 310 helix is a type of secondary structure found in proteins and polypeptides. Of the numerous protein secondary structures present, the 310-helix is the fourth most common type observed; following α-helices, β-sheets and reverse turns. 310-helices constitute nearly 10–15% of all helices in protein secondary structures, and are typically observed as extensions of α-helices found at either their N- or C- termini. Because of the α-helices tendency to consistently fold and unfold, it has been proposed that the 310-helix serves as an intermediary conformation of sorts, and provides insight into the initiation of α-helix folding.
Discovery
Max Perutz, the head of the Medical Research Council Laboratory of Molecular Biology at the University of Cambridge, wrote the first paper documenting the elusive 310-helix. Together with Lawrence Bragg and John Kendrew, Perutz published an exploration of polypeptide chain configurations in 1950, based on cues from noncrystalline diffraction data as well as from small molecule crystal structures such as crystalline found in hair. Their proposals included what is now known as the 310 helix, but did not include the two most common structural motifs now known to occur. The following year, Linus Pauling predicted both of those motifs, the alpha helix and the beta sheet, in work which is now compared in significance to Francis Crick and James D. Watson's publication of the DNA double helix. Pauling was highly critical of the helical structures proposed by Bragg, Kendrew, and Perutz, taking a triumphal tone in declaring them all implausible. Perutz describes in his book I wish I'd made you angry sooner the experience of reading Pauling's paper one Saturday morning:
Later that day, an idea for an experiment to confirm Pauling's model occurred to Perutz, and he rushed to the lab to carry it out. Within a few hours, he had the evidence to confirm the alpha helix, which he showed to Bragg first thing on Mond
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