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https://en.wikipedia.org/wiki/Wireless%20Routing%20Protocol | The Wireless Routing Protocol (WRP) is a proactive unicast routing protocol for mobile ad hoc networks (MANETs).
Description
WRP uses an enhanced version of the distance-vector routing protocol, which uses the Bellman–Ford algorithm to calculate paths. Because of the mobile nature of the nodes within the MANET, the protocol introduces mechanisms which reduce route loops and ensure reliable message exchange.
WRP, similar to Destination-Sequenced Distance Vector routing (DSDV), inherits the properties of the distributed Bellman–Ford algorithm. To counter the count-to-infinity problem and to enable faster convergence, it employs a unique method of maintaining information regarding the shortest distance to every destination node in the network and the penultimate hop node on the path to every destination node. Since WRP, like DSDV, maintains an up-to-date view of the network, every node has a readily available route to every destination node in the network. It differs from DSDV in table maintenance and in the update procedures. While DSDV maintains only one topology table, WRP uses a set of tables to maintain more accurate information. The tables that are maintained by a node are the following: distance table (DT), routing table (RT), link cost table (LCT), and a message retransmission list (MRL).
The DT contains the network view of the neighbors of a node. It contains a matrix where each element contains the distance and the penultimate node reported by a neighbor for a particular destination. The RT contains the up-to-date view of the network for all known destinations. It keeps the shortest distance, the predecessor node (penultimate node), the successor node (the next node to reach the destination), and a flag indicating the status of the path. The path status may be a simple path (correct), or a loop (error), or the destination node not marked (null). The LCT contains the cost (e.g., the number of hops to reach the destination) of relaying messages th |
https://en.wikipedia.org/wiki/Cohesion%20%28geology%29 | Cohesion is the component of shear strength of a rock or soil that is independent of interparticle friction.
In soils, true cohesion is caused by following:
Electrostatic forces in stiff overconsolidated clays (which may be lost through weathering)
Cementing by Fe2O3, Ca CO3, Na Cl, etc.
There can also be apparent cohesion. This is caused by:
Negative capillary pressure (which is lost upon wetting)
Pore pressure response during undrained loading (which is lost through time)
Root cohesion (which may be lost through logging or fire of the contributing plants, or through solution)
Typical values of cohesion
Cohesion (alternatively called the cohesive strength) is typically measured on the basis of Mohr–Coulomb theory. Some values for rocks and some common soils are listed in the table below.
Apparent cohesion of soil
During critical state flow of soil, the undrained cohesion results from effective stress and critical state friction, not chemical bonds between soil particles. All that small clay mineral particles and chemicals do during steady plastic deformation of soft soil is to cause a pore water suction, which can be measured. When we remould soft soil in a classification test, its strength is [(suction) x (friction)], it remains ductile plastic material with constant "apparent cohesion" while it flows at constant volume, because it is at a constant effective stress, and critical state friction is constant. Critical state soil mechanics analyses the bearing capacity of soft clay on the wet side of critical state in terms of a perfectly plastic material with rapid undrained "apparent" cohesion. |
https://en.wikipedia.org/wiki/DSS%20%28NMR%20standard%29 | Sodium trimethylsilylpropanesulfonate (DSS) is the organosilicon compound with the formula (CH3)3SiCH2CH2CH2SO3−Na+. It is the sodium salt of trimethylsilylpropanesulfonic acid. A white, water-soluble solid, it is used as a chemical shift standard for proton NMR spectroscopy of aqueous solutions. The chemical shift, specifically the signal for the trimethylsilyl group, is relatively insensitive to pH.
The proton spectrum of DSS also exhibits resonances at 2.91 ppm (m), 1.75 ppm (m), and 0.63 ppm (m) at an intensity of 22% of the reference resonance at 0 ppm.
Alternatives
Sodium trimethylsilyl propionate (TSP) is a related compound used as an NMR standard. It uses a carboxylic acid instead of the sulfonic acid found in DSS to confer water solubility. As a weak acid, TSP is more sensitive to changes in pH.
4,4-Dimethyl-4-silapentane-1-ammonium trifluoroacetate (DSA) has also been proposed as an alternative, to overcome certain drawbacks of DSS. |
https://en.wikipedia.org/wiki/San%20Francisco%20Historical%20Society | The San Francisco Historical Society is a nonprofit organization dedicated to the preservation, interpretation, and presentation of the history of San Francisco and the surrounding Bay Area. It is a membership-based organization that holds monthly speaking programs, conducts walking tours of San Francisco and publishes original research. It owns the Barbary Coast Trail walking tour and publishes the biannual journal Argonaut.
As of 2021, it has just under 2,000 members.
History
The San Francisco Historical Society was founded in 1988 by historian Charles A. Fracchia.
In February 2002, the San Francisco Historical Society merged with the Museum of the City of San Francisco to create the San Francisco Museum and Historical Society, which the San Francisco municipal government recognized as the official historical museum of San Francisco. One of the purposes of the merger of the two organizations was to put together a single proposal to renovate and operate the Old San Francisco Mint as a history museum.
The San Francisco Museum and Historical Society took over management of the Old Mint in 2004, with plans to make it the museum's permanent home. The organization spent about US$14 million to stabilize and partially renovate the building. However, the building still needed about US$60 million in additional work, and the City of San Francisco concluded the organization was not making progress quickly enough after 11 years of work, so it ordered SFMHS to vacate the building in 2015.
In 2019, the San Francisco Historical Society returned to its original name. In October of that year, the society moved into its first museum space, at 608 Commercial Street, in San Francisco. |
https://en.wikipedia.org/wiki/Schatten%20class%20operator | In mathematics, specifically functional analysis, a pth Schatten-class operator is a bounded linear operator on a Hilbert space with finite pth Schatten norm. The space of pth Schatten-class operators is a Banach space with respect to the Schatten norm.
Via polar decomposition, one can prove that the space of pth Schatten class operators is an ideal in B(H). Furthermore, the Schatten norm satisfies a type of Hölder inequality:
If we denote by the Banach space of compact operators on H with respect to the operator norm, the above Hölder-type inequality even holds for . From this it follows that , is a well-defined contraction. (Here the prime denotes (topological) dual.)
Observe that the 2nd Schatten class is in fact the Hilbert space of Hilbert–Schmidt operators. Moreover, the 1st Schatten class is the space of trace class operators.
Operator theory |
https://en.wikipedia.org/wiki/Operator%20system | Given a unital C*-algebra , a *-closed subspace S containing 1 is called an operator system. One can associate to each subspace of a unital C*-algebra an operator system via .
The appropriate morphisms between operator systems are completely positive maps.
By a theorem of Choi and Effros, operator systems can be characterized as *-vector spaces equipped with an Archimedean matrix order.
See also
Operator space |
https://en.wikipedia.org/wiki/Gleaning%20%28birds%29 | Gleaning is a feeding strategy by birds in which they catch invertebrate prey, mainly arthropods, by plucking them from foliage or the ground, from crevices such as rock faces and under the eaves of houses, or even, as in the case of ticks and lice, from living animals. This behavior is contrasted with hawking insects from the air or chasing after moving insects such as ants. Gleaning, in birds, does not refer to foraging for seeds or fruit.
Gleaning is a common feeding strategy for some groups of birds, including nuthatches, tits (including chickadees), wrens, woodcreepers, treecreepers, Old World flycatchers, Tyrant flycatchers, babblers, Old World warblers, New World warblers, Vireos and some hummingbirds and cuckoos. Many birds make use of multiple feeding strategies, depending on the availability of different sources of food and opportunities of the moment.
Techniques and adaptations
Foliage gleaning, the strategy of gleaning over the leaves and branches of trees and shrubs, can involve a variety of styles and maneuvers. Some birds, such as the common chiffchaff of Eurasia and the Wilson's warbler of North America, feed actively and appear energetic. Some will even hover in the air near a leaf or twig while gleaning from it; this behavior is called "hover-gleaning". Other birds are more methodical in their approach to gleaning, even seeming lethargic as they perch upon and deliberately pick over foliage. This behavior is characteristic of the bay-breasted warbler and many vireos. Another tactic is to hang upside-down from the tips of branches to glean the undersides of leaves. Tits such as the familiar black-capped chickadee are often observed feeding in this manner. Some birds, like the ruby-crowned kinglet and red-eyed vireo of North America use a combination of these tactics.
Gleaning birds are typically small with compact bodies and have small, sharply pointed bills. These features are even seen in gleaning birds that are not closely related. For exam |
https://en.wikipedia.org/wiki/Recycling%20codes | Recycling codes are used to identify the materials out of which the item is made, to facilitate easier recycling process. The presence on an item of a recycling code, a chasing arrows logo, or a resin code, is not an automatic indicator that a material is recyclable; it is an explanation of what the item is made of. Codes have been developed for batteries, biomatter/organic material, glass, metals, paper, and plastics. Various countries have adopted different codes. For example, the table below shows the polymer resin (plastic) codes. In the United States there are fewer, because ABS is placed with "others" in group 7.
A number of countries have a finer-grained system with more recycling codes. For example, China's polymer identification system has seven different classifications of plastic, five different symbols for post-consumer paths, and 140 identification codes. The lack of a code system in some countries has encouraged those who fabricate their own plastic products, such as RepRap and other prosumer 3-D printer users, to adopt a voluntary recycling code based on the more comprehensive Chinese system.
Resin identification codes and codes defined by the European Commission
Chinese codes for plastics products
The Standardization Administration of the People's Republic of China (SAC) has defined material codes for different types of plastics in the document GB 16288-2008. The numbers are consistent with RIC up to #6.
Alternative recycling labels
The following recycling label projects are designed with the consumer in mind while SPI or Resin Identification Codes are designed to be recognized by waste sorting facilities. They provide an alternative that eliminates confusion as people often mistake any resin code to be recyclable, but this is not necessarily true. The recyclability of the numbers depends on the abilities of the facilities in the community. Thus, they are not all automatically recyclable.
How2Recycle is a project that started in 2008. The labe |
https://en.wikipedia.org/wiki/Mycoses%20%28journal%29 | Mycoses: Diagnosis, Therapy and Prophylaxis of Fungal Diseases is a monthly peer-reviewed medical journal covering mycology. It is published by Wiley-Blackwell. The editor-in-chief are Oliver Cornely, Jacques Meis and Martin Schaller. It is the official publication of the Deutschsprachige Mykologische Gesellschaft. The journal covers the pathogenesis, diagnosis, therapy, prophylaxis, and epidemiology of fungal infectious diseases in humans and animals as well as on the biology of pathogenic fungi.
History
The journal was established in 1957 by Heinz Grimmer (Wiesbaden) and published by Medizinische Verlags Anstalt (Berlin) under the title Mykosen (German for "mycoses"). It was originally published in German, but switched 1988 to English. At that time the title was changed to Mycoses.
Abstracting and indexing
According to the Journal Citation Reports, the journal has a 2018 impact factor of 3.065. |
https://en.wikipedia.org/wiki/IDoc | IDoc, short for Intermediate Document, is a SAP document format for business transaction data transfers.
Non SAP-systems can use IDocs as the standard interface (computing) for data transfer.
IDoc is similar to XML in purpose, but differs in syntax. Both serve the purpose of data exchange and automation in computer systems, but the IDoc-Technology takes a different approach.
While XML allows having some metadata about the document itself, an IDoc is obliged to have information at its header like its creator, creation time etc. While XML has a tag-like tree structure containing data and meta-data, IDocs use a table with the data and meta-data. IDocs also have a session that explains all the processes which the document passed or will pass, allowing one to debug and trace the status of the document.
Different IDoc types are available to handle different types of messages. For example, the IDoc format ORDERS01 may be used for both purchase orders and order confirmations.
IDoc technology offers many tools for automation, monitoring and error handling. For example, if the IDocs are customised that way on a particular server, then a user of SAP R/3 system creates a purchase order; this is automatically sent via an IDoc and a sales order is immediately created on the vendor's system.
When this order cannot be created because of an application error (for example: The price per piece is lower than allowed for this material), then the administrator on the vendor's system sees this IDoc among the erroneous ones and can solve the situation. If the error is in the master data at the vendor's system, he can correct them and order the IDoc to be processed again.
Because of the flexibility and transparency of IDoc technology, some non-SAP technologies use them as well.
Structure of the IDoc
An IDoc consists of
Control record (it contains the type of IDoc, port of the partner, release of SAP R/3 which produced the IDoc etc.)
Data records of different types. The number and t |
https://en.wikipedia.org/wiki/Video%20decoder | A video decoder is an electronic circuit, often contained within a single integrated circuit chip, that converts base-band analog video signals to digital video. Video decoders commonly allow programmable control over video characteristics such as hue, contrast, and saturation. A video decoder performs the inverse function of a video encoder, which converts raw (uncompressed) digital video to analog video. Video decoders are commonly used in video capture devices and frame grabbers.
Signals
The input signal to a video decoder is analog video that conforms to a standard format. For example, a standard definition (SD) decoder accepts (composite or S-Video) that conforms to SD formats such as NTSC or PAL. High definition (HD) decoders accept analog HD formats such as AHD, HD-TVI, or HD-CVI.
The output digital video may be formatted in various ways, such as 8-bit or 16-bit 4:2:2, 12-bit 4:1:1, BT.656 (SD) or BT.1120 (HD). Usually, in addition to the digital video output bus, a video decoder will also generate a clock signal and other signals such as:
Sync — indicates the beginning of a video frame
Blanking — indicates video blanking interval
Field — indicates whether the current video field is even or odd (applies to interlaced formats)
Lock — indicates the decoder has detected and is locked (synchronized) to a valid analog input video signal
Functional blocks
The main functional blocks of a video decoder typically include these:
Analog processors
Y/C (luminance/chrominance) separation
Chrominance processor
Luminance processor
Clock/timing processor
A/D converters for Y/C
Output formatter
Host communication interface
Process
Video decoding involves several processing steps. First the analog signal is digitized by an analog-to-digital converter to produce a raw, digital data stream. In the case of composite video, the luminance and chrominance are then separated; this is not necessary for S-Video sources. Next, the chrominance is demodulated to produc |
https://en.wikipedia.org/wiki/Reassignment%20method | The method of reassignment is a technique for sharpening a time-frequency representation by mapping the data to time-frequency coordinates that are nearer to the true region of support of the analyzed signal. The method has been independently introduced by several parties under various names, including method of reassignment, remapping, time-frequency reassignment, and modified moving-window method. In
the case of the spectrogram or the short-time Fourier transform, the method of reassignment sharpens blurry time-frequency data by relocating the data according to local estimates of instantaneous frequency and group delay. This mapping to reassigned time-frequency coordinates is very precise for signals that are separable in time and frequency with respect to the analysis window.
Introduction
Many signals of interest have a distribution of energy that varies in time and frequency. For example, any sound signal having a beginning or an end has an energy distribution that varies in time, and most sounds exhibit considerable variation in both time and frequency over their duration. Time-frequency representations are commonly used to analyze or characterize such signals. They map the one-dimensional time-domain signal into a two-dimensional function of time and frequency. A time-frequency representation describes the variation of spectral energy distribution over time, much as a musical score describes the variation of musical pitch over time.
In audio signal analysis, the spectrogram is the most commonly used time-frequency representation, probably because it is well understood, and immune to so-called "cross-terms" that sometimes make other time-frequency representations difficult to interpret. But the windowing operation required in spectrogram computation introduces an unsavory tradeoff between time resolution and frequency resolution, so spectrograms provide a time-frequency representation that is blurred in time, in frequency, or in both dimensions. The method |
https://en.wikipedia.org/wiki/Harmonic%20wavelet%20transform | In the mathematics of signal processing, the harmonic wavelet transform, introduced by David Edward Newland in 1993, is a wavelet-based linear transformation of a given function into a time-frequency representation. It combines advantages of the short-time Fourier transform and the continuous wavelet transform. It can be expressed in terms of repeated Fourier transforms, and its discrete analogue can be computed efficiently using a fast Fourier transform algorithm.
Harmonic wavelets
The transform uses a family of "harmonic" wavelets indexed by two integers j (the "level" or "order") and k (the "translation"), given by , where
These functions are orthogonal, and their Fourier transforms are a square window function (constant in a certain octave band and zero elsewhere). In particular, they satisfy:
where "*" denotes complex conjugation and is Kronecker's delta.
As the order j increases, these wavelets become more localized in Fourier space (frequency) and in higher frequency bands, and conversely become less localized in time (t). Hence, when they are used as a basis for expanding an arbitrary function, they represent behaviors of the function on different timescales (and at different time offsets for different k).
However, it is possible to combine all of the negative orders (j < 0) together into a single family of "scaling" functions where
The function φ is orthogonal to itself for different k and is also orthogonal to the wavelet functions for non-negative j:
In the harmonic wavelet transform, therefore, an arbitrary real- or complex-valued function (in L2) is expanded in the basis of the harmonic wavelets (for all integers j) and their complex conjugates:
or alternatively in the basis of the wavelets for non-negative j supplemented by the scaling functions φ:
The expansion coefficients can then, in principle, be computed using the orthogonality relationships:
For a real-valued function f(t), and so one can cut the number of independent expansi |
https://en.wikipedia.org/wiki/Phi%20bond | In chemistry, phi bonds (φ bonds) are covalent chemical bonds, where six lobes of one involved atomic orbital overlap six lobes of the other involved atomic orbital. This overlap leads to the formation of a bonding molecular orbital with three nodal planes which contain the internuclear axis and go through both atoms.
The Greek letter φ in their name refers to f orbitals, since the orbital symmetry of the φ bond is the same as that of the usual (6-lobed) type of f orbital when seen down the bond axis.
There was one possible candidate known in 2005 of a molecule with phi bonding (a U−U bond, in the molecule U2). However, later studies that accounted for spin orbit interactions found that the bonding was only of fourth order. Experimental evidence of existence of phi bonding between a thorium atom and cyclooctatetraene in thorocene has been shown, supported by computational analysis. |
https://en.wikipedia.org/wiki/Russian%20floating%20nuclear%20power%20station | Floating nuclear power stations () are vessels designed by Rosatom, the Russian state-owned nuclear energy corporation. They are self-contained, low-capacity, floating nuclear power plants. Rosatom plans to mass-produce the stations at shipbuilding facilities and then tow them to ports near locations that require electricity.
The work on such a concept dates back to the MH-1A in the United States, which was built in the 1960s into the hull of a World War II Liberty Ship, which was followed on much later in 2022 when the United States Department of Energy funded a three-year research study of offshore floating nuclear power generation. The Rosatom project is the first floating nuclear power plant intended for mass production. The initial plan was to manufacture at least seven of the vessels by 2015. On 14 September 2019, Russia’s first-floating nuclear power plant, Akademik Lomonosov, arrived to its permanent location in the Chukotka region. It started operation on 19 December 2019.
History
The project for a floating nuclear power station began in 2000, when the Ministry for Atomic Energy of the Russian Federation (Rosatom) chose Severodvinsk in Arkhangelsk Oblast as the construction site, Sevmash was appointed as general contractor.
Construction of the first power station, the Akademik Lomonosov, started on 15 April 2007 at the Sevmash Submarine-Building Plant in Severodvinsk.
In August 2008 construction works were transferred to the Baltic Shipyard in Saint Petersburg, which is also responsible for the construction of future vessels.
Akademik Lomonosov was launched on 1 July 2010, at an estimated cost of 6 billion rubles (232 m$).
In 2015 construction of a second vessel starting in 2019 was announced by Russia's state nuclear corporation Rosatom.
On 27 July 2021 Rosatom signed an agreement with GDK Baimskaya LLC for energy delivery for Baimskaya copper mining operations. Rosatom suggests delivering up to three new floating power plants (with fourth being in |
https://en.wikipedia.org/wiki/Mesencephalic%20nucleus%20of%20trigeminal%20nerve | The mesencephalic nucleus of trigeminal nerve is one of the sensory nuclei of the trigeminal nerve (cranial nerve V). It is located in the brainstem. It receives proprioceptive sensory information from the muscles of mastication and other muscles of the head and neck. It is involved in processing information about the position of the jaw/teeth. It is functionally responsible for preventing excessive biting that may damage the dentition, regulating tooth pain perception, and mediating the jaw jerk reflex (by means of projecting to the motor nucleus of the trigeminal nerve).
The axons of the neuron cell bodies of this nucleus provide sensory innervation to target tissues directly, whereas other sensory nuclei of the trigeminal nerve receive their sensory inputs by synapsing with primary sensory neurons in the trigeminal ganglion.
Anatomy
The MNTN is located in the brainstem, more specifically (sources vary) spanning the length of the midbrain/in the caudal midbrain and rostral pons. It is situated (sources vary) near/within the periaqueductal gray, lateral to the cerebral aqueduct.
The mesencephalic nucleus is the only structure in the central nervous system to contain the cell bodies of first order sensory neurons. The mesencephalic nucleus can thus be considered functionally as a primary sensory ganglion embedded within the brainstem, making it neuroanatomically unique.
Microanatomy
Unlike many nuclei within the central nervous system (CNS), the mesencephalic nucleus contains no chemical synapses but are electrically coupled. Neurons of this nucleus are pseudounipolar, receiving proprioceptive afferent information from the mandible and sending efferent projections to the trigeminal motor nucleus to mediate monosynaptic jaw jerk reflexes.
Development
The pseudounipolar neurons in the mesencephalic nucleus are embryologically derived from the neural crest. However, instead of joining the trigeminal ganglion, the neurons migrate into the brainstem. The MNTN is |
https://en.wikipedia.org/wiki/Panorama%20Software | Panorama Software is a Canadian software and consulting company specializing in business intelligence. The company was founded by Rony Ross in Israel in 1993; it relocated its headquarters to Toronto, Canada in 2003.
Panorama sold its online analytical processing (OLAP) technology to Microsoft in 1996, which was built into Microsoft OLAP Services and later SQL Server Analysis Services, an integrated component of Microsoft SQL Server.
Products
The company’s main product is a business intelligence (BI) suite named Necto.
Before 2011 it had a product called NovaView.
Necto offers data mining and report generation, allowing custom views of the data without having to wait to run a report. It lets users create collaborative "workboards" and visual presentations. The users are able discover those who are attempting to analyze similar data sets. The company contends this focus on social analysis leads, starting with business data and connecting it with the people who are involved in this data.
Necto is a BI application based upon understanding of user behavior, one-click reporting, and collaborative decision making. It supports social sharing of data, similar to sharing found on consumer oriented social networking sites. Data analysis is treated as "conversations" which can themselves be followed and analyzed. Panorama encourages Necto enterprise users to form cross-departmental teams based on data research behaviors. It allows tracking of user behavior and making corresponding adjustments.
Necto includes analytics, custom reporting, intuitive dashboards, and integration with Microsofttechnology. It can use data sources including spreadsheets, in-memory, OLAP, or relational databases. Integration on Microsoft Azure and optimization with Microsoft SQL Server 2012 platform is also available. Necto integrates with SharePoint. It can be scaled up to manage thousands of users and several terabytes of data.
Panorama and Microsoft
Panorama Software is the original develope |
https://en.wikipedia.org/wiki/Structural%20risk%20minimization | Structural risk minimization (SRM) is an inductive principle of use in machine learning. Commonly in machine learning, a generalized model must be selected from a finite data set, with the consequent problem of overfitting – the model becoming too strongly tailored to the particularities of the training set and generalizing poorly to new data. The SRM principle addresses this problem by balancing the model's complexity against its success at fitting the training data. This principle was first set out in a 1974 paper by Vladimir Vapnik and Alexey Chervonenkis and uses the VC dimension.
In practical terms, Structural Risk Minimization is implemented by minimizing , where is the train error, the function is called a regularization function, and is a constant. is chosen such that it takes large values on parameters that belong to high-capacity subsets of the parameter space. Minimizing in effect limits the capacity of the accessible subsets of the parameter space, thereby controlling the trade-off between minimizing the training error and minimizing the expected gap between the training error and test error.
The SRM problem can be formulated in terms of data. Given n data points consisting of data x and labels y, the objective is often expressed in the following manner:
The first term is the mean squared error (MSE) term between the value of the learned model, , and the given labels . This term is the training error, , that was discussed earlier. The second term, places a prior over the weights, to favor sparsity and penalize larger weights. The trade-off coefficient, , is a hyperparameter that places more or less importance on the regularization term. Larger encourages sparser weights at the expense of a more optimal MSE, and smaller relaxes regularization allowing the model to fit to data. Note that as the weights become zero, and as , the model typically suffers from overfitting.
See also
Vapnik–Chervonenkis theory
Support vector machines
Model s |
https://en.wikipedia.org/wiki/Isochore%20%28genetics%29 | In genetics, an isochore is a large region of genomic DNA (greater than 300 kilobases) with a high degree of uniformity in GC content; that is, guanine (G) and cytosine (C) bases. The distribution of bases within a genome is non-random: different regions of the genome have different amounts of G-C base pairs, such that regions can be classified and identified by the proportion of G-C base pairs they contain.
Bernardi and colleagues first noticed the compositional non-uniformity of vertebrate genomes using thermal melting and density gradient centrifugation.
The DNA fragments extracted by the gradient centrifugation were later termed "isochores", which was subsequently defined as "very long (much greater than 200 KB) DNA segments" that "are fairly homogeneous in base composition and belong to a small number of major classes distinguished by differences in guanine-cytosine (GC) content". Subsequently, the isochores "grew" and were claimed to be ">300 kb in size."
The theory proposed that the isochore composition of genomes varies markedly between "warm-blooded" (homeotherm) vertebrates and "cold-blooded" (poikilotherm) vertebrates and later became known as the isochore theory.
The thermodynamic stability hypothesis
The isochore theory purported that the genome of "warm-blooded" vertebrates (mammals and birds) are mosaics of long isochoric regions of alternating GC-poor and GC-rich composition, as opposed to the genome of "cold-blooded" vertebrates (fishes and amphibians) that were supposed to lack GC-rich isochores.
These findings were explained by the thermodynamic stability hypothesis, attributing genomic structure to body temperature. GC-rich isochores were purported to be a form of adaptation to environmental pressures, as an increase in genomic GC-content could protect DNA, RNA, and proteins from degradation by heat.
Despite its attractive simplicity, the thermodynamic stability hypothesis has been repeatedly shown to be in error
.
Many authors show |
https://en.wikipedia.org/wiki/Bundle%20metric | In differential geometry, the notion of a metric tensor can be extended to an arbitrary vector bundle, and to some principal fiber bundles. This metric is often called a bundle metric, or fibre metric.
Definition
If M is a topological manifold and : E → M a vector bundle on M, then a metric on E is a bundle map k : E ×M E → M × R from the fiber product of E with itself to the trivial bundle with fiber R such that the restriction of k to each fibre over M is a nondegenerate bilinear map of vector spaces. Roughly speaking, k gives a kind of dot product (not necessarily symmetric or positive definite) on the vector space above each point of M, and these products vary smoothly over M.
Properties
Every vector bundle with paracompact base space can be equipped with a bundle metric. For a vector bundle of rank n, this follows from the bundle charts : the bundle metric can be taken as the pullback of the inner product of a metric on ; for example, the orthonormal charts of Euclidean space. The structure group of such a metric is the orthogonal group O(n).
Example: Riemann metric
If M is a Riemannian manifold, and E is its tangent bundle TM, then the Riemannian metric gives a bundle metric, and vice versa.
Example: on vertical bundles
If the bundle :P → M is a principal fiber bundle with group G, and G is a compact Lie group, then there exists an Ad(G)-invariant inner product k on the fibers, taken from the inner product on the corresponding compact Lie algebra. More precisely, there is a metric tensor k defined on the vertical bundle E = VP such that k is invariant under left-multiplication:
for vertical vectors X, Y and Lg is left-multiplication by g along the fiber, and Lg* is the pushforward. That is, E is the vector bundle that consists of the vertical subspace of the tangent of the principal bundle.
More generally, whenever one has a compact group with Haar measure μ, and an arbitrary inner product h(X,Y) defined at the tangent space of some point in G, one can |
https://en.wikipedia.org/wiki/Therapeutic%20inertia | Therapeutic inertia (also known as clinical inertia) is a measurement of the resistance to therapeutic treatment for an existing medical condition. It is commonly measured as a percentage of the number of encounters in which a patient with a condition received new or increased therapeutic treatment out of the total number of visits to a health care professional by the patient. A high percentage indicates that the health care provider is slow to treat a medical condition. A low percentage indicates that a provider is extremely quick in prescribing new treatment at the onset of any medical condition.
Calculation
There are two common methods used in calculating therapeutic inertia. For the following examples, consider that a patient has five visits with a health provider. In four of those visits, a condition is not controlled (such as high blood pressure or high cholesterol). In two of those visits, the provider made a change to the patient's treatment for the condition.
In Dr. Okonofua's original paper, this patient's therapeutic inertia is calculated as where h is the number of visits with an uncontrolled condition, c is the number of visits in which a change was made, and v is the total number of visits. Therefore, the patient's therapeutic inertia is .
An alternative, which avoids consideration of visits where the condition was already controlled and the provider should not be expected to make a treatment change, is . Using the above example, there are 2 changes and 4 visits with an uncontrolled condition. The therapeutic inertia is .
Reception
Therapeutic inertia was devised as a metric for measuring treatment of hypertension. It has now become a standard metric for analysing treatment of many common comorbidities such as diabetes and hyperlipidemia. Both feedback reporting processes and intervention studies aimed at reducing therapeutic inertia have been shown to increase control of hypertension, diabetes, and hyperlipidemia. |
https://en.wikipedia.org/wiki/High%20Capacity%20Color%20Barcode | High Capacity Color Barcode (HCCB) is a technology developed by Microsoft for encoding data in a 2D "barcode" using clusters of colored triangles instead of the square pixels conventionally associated with 2D barcodes or QR codes. Data density is increased by using a palette of 4 or 8 colors for the triangles, although HCCB also permits the use of black and white when necessary. It has been licensed by the ISAN International Agency for use in its International Standard Audiovisual Number standard, and serves as the basis for the Microsoft Tag mobile tagging application.
The technology was created by Gavin Jancke, an engineering director at Microsoft Research. Quoted by BBC News in 2007, he said that HCCB was not intended to replace conventional barcodes. "'It's more of a 'partner' barcode', he said. 'The UPC barcodes will always be there. Ours is more of a niche barcode where you want to put a lot of information in a small space.'"
Technology
HCCB uses a grid of colored triangles to encode data. Depending on the target use, the grid size (total number of symbols), symbol density (the printed size of the triangles), and symbol count (number of colors used) can be varied. HCCB can use an eight-, four-, or two-color (black-and-white) palette. Microsoft claims that laboratory tests using standard off-the-shelf printers and scanners have yielded readable eight-color HCCBs equivalent to approximately 3,500 characters per square inch.
Microsoft Tag
Microsoft Tag is a discontinued but still available implementation of High Capacity Color Barcode (HCCB) using 4 colors in a 5 x 10 grid. Additionally, the code works in monochrome. The print size can be varied to allow reasonable reading by a mobile camera phone; for example, a Tag on a real estate sign might be printed large enough to be read from a car driving by, whereas a Tag in a magazine could be smaller because the reader would likely be nearer.
A Microsoft Tag is essentially a machine readable web link, analo |
https://en.wikipedia.org/wiki/Reversible%20reference%20system%20propagation%20algorithm | Reversible reference system propagation algorithm (r-RESPA) is a time stepping algorithm used in molecular dynamics.
It evolves the system state over time,
where the L is the Liouville operator. |
https://en.wikipedia.org/wiki/DIG64 | DIG64 or Developers' Interface Guide for 64-bit Intel Architecture Servers was an alliance between several leading technology companies including Groupe Bull, Fujitsu Siemens, Hitachi, HP, Intel, NEC, and Unisys.
The corporation had responsibility for driving for interoperability on Itanium platforms. To do this they supported a specification, also called DIG64, that helped member companies develop better and more compelling products on Itanium processor family architecture systems. |
https://en.wikipedia.org/wiki/DVB-RCS | DVB-RCS (Digital Video Broadcasting - Return Channel via Satellite) provides a method by which the DVB-S platform (and in theory also the DVB-S2 platform) can become a bi-directional, asymmetric data path using wireless between broadcasters and customers. It is a specification for an interactive on-demand multimedia satellite communication system formulated in 1999 by the DVB consortium. Without this method, various degrees of interactivity can be offered, without implying any return channel back from the user to the service provider: Data Carrousel or Electronic Programs Guides (EPG) are examples of such enhanced TV services which make use of “local interactivity”, without any return path from customer to provider.
Chronology
The 5th revision of the DVB-RCS standard was completed in 2008. A major update included the very first broadband mobile standardization. This extended version, formally referred to as "ETSI EN 301 790 v 1.5.1" is also known as "DVB-RCS+M". The "+M" version added several new features, such as the ability to use "DVB-S2" bursts in the uplink channel back to the satellite. It incorporated signal fade mitigation techniques and other solutions to combat short term signal loss.
In contrast to other satellite communications systems, DVB-RCS was created in an open environment where any DVB member can participate. DVB membership is open to all companies willing to subscribe. The work group called "DVB TM-RCS" is currently pursuing other technical solutions for the approved commercial system.
In 2009 technical work started for a new version of DVB-RCS called "DVB-RCS NG" (Next Generation). In this more powerful version of the standard "RCS2" there will be support for Higher Layers for Satellite (HLS) communication.
Evolution
In older systems, interactive video broadcasting was possible as a result of using physical cables for connectivity. However, in remote areas cable connections may be unavailable, two-way communication was then impossible via |
https://en.wikipedia.org/wiki/Design%20rationale | A design rationale is an explicit documentation of the reasons behind decisions made when designing a system or artifact. As initially developed by W.R. Kunz and Horst Rittel, design rationale seeks to provide argumentation-based structure to the political, collaborative process of addressing wicked problems.
Overview
A design rationale is the explicit listing of decisions made during a design process, and the reasons why those decisions were made. Its primary goal is to support designers by providing a means to record and communicate the argumentation and reasoning behind the design process.
It should therefore include:
the reasons behind a design decision,
the justification for it,
the other alternatives considered,
the trade offs evaluated, and
the argumentation that led to the decision.
Several science areas are involved in the study of design rationales, such as computer science cognitive science, artificial intelligence, and knowledge management. For supporting design rationale, various frameworks have been proposed, such as QOC, DRCS, IBIS, and DRL.
History
While argumentation formats can be traced back to Stephen Toulmin's work in the 1950s datums, claims, warrants, backings and rebuttals, the origin of design rationale can be traced back to W.R. Kunz and Horst Rittel's development of the Issue-Based Information System (IBIS) notation in 1970. Several variants on IBIS have since been proposed.
The first was Procedural Hierarchy of Issues (PHI), first described in Ray McCall's PhD Dissertation although not named at the time.
IBIS was also modified, in this case to support Software Engineering, by Potts & Bruns. The Potts & Bruns approach was then extended by the Decision Representation Language (DRL). which itself was extended by RATSpeak.
Questions Options and Criteria (QOC), also known as Design Space Analysis is an alternative representation for argumentation-based rationale, as are Win-Win and the Decision Recommendation and Intent Model |
https://en.wikipedia.org/wiki/Torkel%20Franz%C3%A9n | Torkel Franzén (1 April 1950, Norrbotten County – 19 April 2006, Stockholm) was a Swedish academic.
Biography
Franzén worked at the Department of Computer Science and Electrical Engineering at Luleå University of Technology, Sweden, in the fields of mathematical logic and computer science. He was known for his work on Gödel's incompleteness theorems and for his contributions to Usenet. He was active in the online science fiction fan community, and even issued his own electronic fanzine Frotz on his fiftieth birthday. He died of bone cancer at age 56.
Selected works
Gödel's Theorem: An Incomplete Guide to its Use and Abuse. Wellesley, Massachusetts: A K Peters, Ltd., 2005. x + 172 pp. .
Inexhaustibility: A Non-Exhaustive Treatment. Wellesley, Massachusetts: A K Peters, Ltd., 2004. Lecture Notes in Logic, #16, Association for Symbolic Logic. .
The Popular Impact of Gödel's Incompleteness Theorem, Notices of the American Mathematical Society, 53, #4 (April 2006), pp. 440–443.
Provability and Truth (Acta universitatis stockholmiensis, Stockholm Studies in Philosophy 9) (1987)
See also
Gödel's incompleteness theorems |
https://en.wikipedia.org/wiki/Polymerase%20chain%20reaction%20optimization | The polymerase chain reaction (PCR) is a commonly used molecular biology tool for amplifying DNA, and various techniques for PCR optimization which have been developed by molecular biologists to improve PCR performance and minimize failure.
Contamination and PCR
The PCR method is extremely sensitive, requiring only a few DNA molecules in a single reaction for amplification across several orders of magnitude. Therefore, adequate measures to avoid contamination from any DNA present in the lab environment (bacteria, viruses, or human sources) are required. Because products from previous PCR amplifications are a common source of contamination, many molecular biology labs have implemented procedures that involve dividing the lab into separate areas. One lab area is dedicated to preparation and handling of pre-PCR reagents and the setup of the PCR reaction, and another area to post-PCR processing, such as gel electrophoresis or PCR product purification. For the setup of PCR reactions, many standard operating procedures involve using pipettes with filter tips and wearing fresh laboratory gloves, and in some cases a laminar flow cabinet with UV lamp as a work station (to destroy any extraneomultimer formation). PCR is routinely assessed against a negative control reaction that is set up identically to the experimental PCR, but without template DNA, and performed alongside the experimental PCR.
Hairpins
Secondary structures in the DNA can result in folding or knotting of DNA template or primers, leading to decreased product yield or failure of the reaction. Hairpins, which consist of internal folds caused by base-pairing between nucleotides in inverted repeats within single-stranded DNA, are common secondary structures and may result in failed PCRs.
Typically, primer design that includes a check for potential secondary structures in the primers, or addition of DMSO or glycerol to the PCR to minimize secondary structures in the DNA template, are used in the optimization |
https://en.wikipedia.org/wiki/Basidiolichen | Basidiolichens are lichenized members of the Basidiomycota, a much smaller group of lichens than the far more common ascolichens in the Ascomycota. In arctic, alpine, and temperate forests, the most common basidiolichens are in the agaric genus Lichenomphalia (including former members of Omphalina or Gerronema) and the clavarioid genus Multiclavula. Several lichenized genera occur in tropical regions, the most common being the foliose Dictyonema. Previously basidiolichens had been classified in their own subclass, Basidiolichenes. Molecular based phylogeny does not support classification of the genera together. |
https://en.wikipedia.org/wiki/Edinburgh%20Concurrent%20Supercomputer | The Edinburgh Concurrent Supercomputer (ECS) was a large Meiko Computing Surface supercomputer. This transputer-based, massively parallel system was installed at the University of Edinburgh during the late 1980s and early 1990s.
History
Following a pilot project involving an early 40-transputer Computing Surface installed in April 1986, funding was obtained from SERC and the DTI for a much larger system using T800 transputers and a MicroVAX fileserver. The Edinburgh Concurrent Supercomputer Project (ECSP) was formed to manage and support the facility, which was commissioned at the end of 1987.
Over the next few years, the system received several upgrades, including more transputers (reaching, at its peak, around 400 processors) and the installation of M²VCS and MeikOS system software, which enabled multi-user access and removed the need for the MicroVAX.
In 1990, the Edinburgh Concurrent Supercomputer Project was succeeded by the Edinburgh Parallel Computing Centre, which consolidated the project with other parallel computing resources and activities within the University. The ECS continued to be used for a variety of academic and commercial research work.
In October 1992 the ECS was reconfigured as a SPARC-hosted Computing Surface with three SPARC "host" processors running SunOS and around 380 T800s. The system was finally decommissioned in August 1994. |
https://en.wikipedia.org/wiki/Torsion%20%28gastropod%29 | Torsion is a gastropod synapomorphy which occurs in all gastropods during larval development. Torsion is the rotation of the visceral mass, mantle, and shell 180˚ with respect to the head and foot of the gastropod. This rotation brings the mantle cavity and the anus to an anterior position above the head.
In some groups of gastropods (Opisthobranchia) there is a degree of secondary detorsion or rotation towards the original position; this may be only partial detorsion or full detorsion.
The torsion or twisting of the visceral mass of larval gastropods is not the same thing as the spiral coiling of the shell, which is also present in many shelled gastropods.
Development
There are two different developmental stages which cause torsion. The first stage is caused by the development of the asymmetrical velar/foot muscle which has one end attached to the left side of the shell and the other end has fibres attached to the left side of the foot and head. At a certain point in larval development this muscle contracts, causing an anticlockwise rotation of the visceral mass and mantle of roughly 90˚. This process is very rapid, taking from a few minutes to a few hours. After this transformation the second stage of torsion development is achieved by differential tissue growth of the left hand side of the organism compared to the right hand side. This second stage is much slower and rotates the visceral mass and mantle a further 90˚. Detorsion is brought about by reversal of the above phases.
During torsion the visceral mass remains almost unchanged anatomically. There are, however, other important changes to other internal parts of the gastropod. Before torsion the gastropod has an euthyneural nervous system, where the two visceral nerves run parallel down the body. Torsion results in a streptoneural nervous system, where the visceral nerves cross over in a figure of eight fashion. As a result, the parietal ganglions end up at different heights. Because of differences betw |
https://en.wikipedia.org/wiki/Hamilton%20Wetland%20Restoration%20Project | The Hamilton Wetland Restoration Project, now known as the Hamilton/Bel Marin Keys Wetlands Restoration, is a wetlands habitat restoration project at the former Hamilton Air Force Base—Hamilton Army Airfield (1930−1988) site and adjacent Bel Marin Keys shoreline, in Marin County, California.
It is located at Whiteside Marsh on the northwestern shore of San Pablo Bay, in and adjacent to the city of Novato in the North Bay region of the San Francisco Bay Area.
Project
The restoration project is a joint venture between two public agencies: the U.S. Army Corps of Engineers is the lead federal agency, with the California Coastal Conservancy as the local sponsoring agency. In addition, the San Francisco Bay Conservation and Development Commission serves as a collaborating partner.
The U.S. Congress authorized the Hamilton Wetland Restoration Project in 1999, and the addition of the Bel Marin Keys property to the project in 2007. The combined project site comprises approximately .
Together, these three agencies are working to restore the Whiteside Marsh section of the closed Hamilton Air Force Base—Hamilton Army Airfield site to its former natural estuary and wetlands condition, and to create valuable endangered species habitat in the urbanized San Francisco Bay Area.
The Hamilton Wetlands Restoration Project "represents an unprecedented opportunity to contribute to the restoration of the San Francisco Bay, which has lost over 85% of its natural wetlands since the 1880s."
External links
San Pablo Bay
Wetlands of the San Francisco Bay Area
Ecological restoration
Estuaries of California
Landforms of Marin County, California
Natural history of Marin County, California
Protected areas of Marin County, California
Protected areas established in 1999
1999 establishments in California
Environment of the San Francisco Bay Area |
https://en.wikipedia.org/wiki/Osmostat | The osmostat is the regulatory center in the hypothalamus that controls the osmolality of the extracellular fluid. The area in the anterior region of the hypothalamus contains the osmoreceptors, cells that control osmolality via the secretion of antidiuretic hormone (ADH).
In neurological conditions such as epilepsy or paraplegia, the osmostat can be pathologically reset, secreting ADH at a lower osmolality, which may cause hyponatremia. A reset osmostat is also a feature of SIADH. |
https://en.wikipedia.org/wiki/Simazine | Simazine is an herbicide of the triazine class. The compound is used to control broad-leaved weeds and annual grasses.
Preparation
Simazine may be prepared from cyanuric chloride and a concentrated solution of ethyl amine (at least 50 percent by number) in water. The reaction is highly exothermic and is therefore best carried out in an ice bath below 10 °C. It is also essential to carry out the synthesis in a fume hood since cyanuric chloride decomposes at high temperatures into hydrogen chloride and hydrogen cyanide, both of which are highly toxic by inhalation.
Properties and uses
Simazine is an off-white crystalline compound which is sparingly soluble in water. It is a member of the triazine-derivative herbicides, and was widely used as a residual non-selective herbicide, but is now banned in European Union states. Like atrazine, a related triazine herbicide, it acts by inhibiting photosynthesis. It remains active in the soil for two to seven months or longer after application.
See also
Atrazine |
https://en.wikipedia.org/wiki/Samsung%20U750%20Alias%202 | The Samsung SCH-U750, marketed as Samsung Alias 2 and also as Samsung Zeal, was a cell phone made by Samsung. The phone was only available in metallic gray. It features a dual-hinge design that can be opened in portrait or landscape style. The Alias 2 featured an E Ink-based keyboard. In horizontal mode it features a QWERTY keyboard and VCAST music on the Verizon Wireless network within Australia and the USA.
The phone ran on Verizon Wireless's digital and Ev-DO networks until the shutdown of Verizon's 3G networks. The Samsung Alias 2 was released on 11 May 2009 in the United States.
Features
Its external features are a postage stamp sized front display, touch sensitive music control buttons and a 2.0-megapixel camera. On the right side there is the power button, a "hold" button, and a microSD card slot. On the left, there is a Voice Activation button, an up/down volume rocker button, a headphone jack, and proprietary charger/data transfer port. Opened in portrait or call mode, a standard numerical dialing pad along with two soft keys, send and end keys, a camera button, a voice command button, and four-directional buttons with an OK key in the center are all available. When in portrait, a user could input text using T9 (predictive text) or flip the phone horizontally for its full keyboard. The phone's 2.0 megapixel camera can take up to 1200 x 1600, and can record video at 176 x 144 at 15fps for the maximum of 10 minutes. The user could also use features in the camera like Night Shot, multi-shot, panorama, self-timer, and various filters. The smaller 128 x 128 1.3 inch display would also display what the camera would be showing when taking pictures of yourself. Opened horizontally, the full QWERTY keypad is usable and a simple button press allows switching between the various alphanumeric functions. Stereo speakers are mounted on either side of the 2.6-inch TFT display, with a resolution of 240 x 320 (QVGA). The battery is 880 mAh which will give you 5 hours o |
https://en.wikipedia.org/wiki/Haplogroup%20L4 | Haplogroup L4 is a human mitochondrial DNA (mtDNA) haplogroup. It is a small maternal clade primarily restricted to Africa.
L4 is important in East Africa. The highest frequencies are in Tanzania among the Hadza at 60-83% and Sandawe at 48%.
It has two branches, L4a and L4b. Subgroup L4a was formerly called L7 and considered a separate subclade of L3'4'7. It has been recognized as a subclade of L4, with L3 as its outgroup by Behar et al. (2008).
The parent clade L3'4 is to have emerged at 106–66 kya.
L4 is not much later than this, estimated at 87 kya by Fernandes et al. (2015).
Phylogeny
The following phylogeny is based on van Oven and Kayser (2008).
L3'4
L4
L4a (formerly known as L7), mutations: 195C, 3357, 5460, 10373, 11253, 11344, 11485, 12414, 13174, 14302, 16260.
L4a1
L4a1a
L4a2
L4b, mutations: 709, 3918.
L4b1
L4b2 (formerly known as L3g or L4g)
L4b2a
L4b2a1
L4b2a2
L4b2a2a
L4b2a2b
L4b2b |
https://en.wikipedia.org/wiki/Haplogroup%20L5 | Haplogroup L5 is a human mitochondrial DNA (mtDNA) clade. It was previously known as L1e.
Distribution
L5 is a small haplogroup centered in East Africa. The highest frequency is in Mbuti Pygmies from Eastern Central Africa at 15%.
It is present in relatively small frequencies in Tanzania (Sandawe and others), Kenya, Chad, Ethiopia, Sudan, Nubia, Egypt and Saudi Arabia.
Haplogroup L5 has been observed among specimens at the island cemetery in Kulubnarti, Sudan, which date from the Early Christian period (AD 550–800).
Subclades
Tree
This phylogenetic tree of haplogroup L5 subclades is based on the paper by Mannis van Oven and Manfred Kayser Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation and subsequent published research.
Most Recent Common Ancestor (MRCA)
L1-6
L2-6
L5
L5a
L5a1
L5a1a
L5a1b
L5a1c
L5a2
L5c
L5c1
L5c2 |
https://en.wikipedia.org/wiki/Haplogroup%20L6 | In human mitochondrial genetics, Haplogroup L6 is a human mitochondrial DNA (mtDNA) haplogroup. It is a small African haplogroup.
Distribution
This haplogroup has been found most often in Yemen and Ethiopia.
Subclades
Tree
This phylogenetic tree of haplogroup M subclades is based on the paper by Mannis van Oven and Manfred Kayser Updated comprehensive phylogenetic tree of global human mitochondrial DNA variation and subsequent published research.
L3'4'6
L6
L6a
L6b
See also
Genealogical DNA test
Genetic genealogy
Human mitochondrial genetics
Population genetics
Human mitochondrial DNA haplogroups |
https://en.wikipedia.org/wiki/Watershed%20area%20%28medical%29 | Watershed area is the medical term referring to regions of the body, that receive dual blood supply from the most distal branches of two large arteries, such as the splenic flexure of the large intestine. The term refers metaphorically to a geological watershed, or drainage divide, which separates adjacent drainage basins.
During times of blockage of one of the arteries that supply the watershed area, such as in atherosclerosis, these regions are spared from ischemia by virtue of their dual supply. However, during times of systemic hypoperfusion, such as in disseminated intravascular coagulation or heart failure, these regions are particularly vulnerable to ischemia because they are supplied by the most distal branches of their arteries, and thus the least likely to receive sufficient blood.
Watershed areas are found in the brain, where areas are perfused by both the anterior and middle cerebral arteries, and in the intestines, where areas are perfused by both the superior and inferior mesenteric arteries (i.e., splenic flexure). Additionally, the sigmoid colon and rectum form a watershed zone with blood supply from inferior mesenteric, pudendal and iliac circulations. Hypoperfusion in watershed areas can lead to mural and mucosal infarction in the case of ischemic bowel disease. When watershed stroke occurs in the brain, it produces unique focal neurologic symptoms that aid clinicians in diagnosis and localization. For example, a cerebral watershed area is situated in the dorsal prefrontal cortex; when it is affected on the left side, this can lead to transcortical motor aphasia. |
https://en.wikipedia.org/wiki/Protease-sparing%20regimen | Protease-sparing regimen, often abbreviated as PSR, is a method or therapy for treating people infected with HIV that involves a three-drug combination that reduces viral load below the limit of detection while saving protease inhibitors for later use. It is considered a weaker (in terms of quantity and concentration) form of HIV treatment. It has been argued that such a regimen is not as potent as giving HIV patients with the strongest drugs as soon as it is detected. Others believe that this might be considered a long-term strategy in order to reduce the amount of HIV, and in some instances have proven to be successful.
See also
Protease
Women's Interagency HIV Study |
https://en.wikipedia.org/wiki/GNOME%20Devhelp | Devhelp is a GTK/GNOME browser for API documentation; it works natively with gtk-doc (which is the API reference format for GTK/GNOME documentation).
It is integrated in GNOME development tools such as GNOME Builder, Glade and Anjuta, and is an official application of the GNOME project. Devhelp uses Bonobo for integration to Emacs via command line searches and is embedded in other development applications such as Anjuta.
Devhelp uses the GTK port of WebKit for HTML rendering of documentation; versions prior to 0.22 used Gecko, a layout engine developed by Mozilla Corporation and used in the Firefox web browser. |
https://en.wikipedia.org/wiki/SxS | SxS (S-by-S) is a flash memory standard compliant to the Sony and SanDisk-created ExpressCard standard. According to Sandisk and Sony, the cards have transfer rates of 800 Mbit/s and burst transfer rate of up to 2.5 Gbit/s over the ExpressCard's PCI Express interface. Sony uses these cards as the storage medium for their XDCAM EX line of professional video cameras.
Compatibility
The card can be inserted directly into an ExpressCard slot, available on many notebooks. However, it will only work in Windows and Mac OS X, and only with a Sony device driver installed on the machine. Experimental Linux drivers are also available.
The only universal connectivity for these cards is the Sony SBAC-US10 and Sony SBAC-US20. These external USB adapters will make the cards visible to any system as an external USB hard drive. The Sony SBAC-US20 uses the USB 3.0 interface and has a suggested retail price of US$350.
SxS PRO+
SxS PRO+ is a faster version of SxS designed for the recording of 4K resolution video. SxS Pro+ has a guaranteed minimum recording speed of 1.3 Gbit/s and an interface with a theoretical maximum speed of 8 Gbit/s.
SxS PRO+ media cards are used on three CineAlta cameras which are the Sony PMW-F55 Sony PMW-F5, and the Sony Venice. The XAVC recording format can record 4K resolution at 60 fps with 4:2:2 chroma subsampling at 600 Mbit/s. A 128 Gigabyte SxS PRO+ media card can record up to 20 minutes of 4K resolution XAVC video at 60 fps, up to 40 minutes of 4K resolution XAVC video at 30 fps, and up to 120 minutes of 2K resolution XAVC video at 30 fps.
See also
P2 (storage media)
XAVC - A recording format that can be used with SxS PRO+ media cards |
https://en.wikipedia.org/wiki/Fishery%20Resources%20Monitoring%20System | The Fishery Resources Monitoring System (FIRMS) is a partnership of intergovernmental fisheries organizations that share information on the global monitoring and management of marine fishery resources.
Activities
FIRMS draws together a unified partnership of international organizations, regional fishery bodies collaborating within a formal agreement to report and share information on fisheries resources.
The Secretariat and system maintenance are part of the FAO Regular Programme (Food and Agriculture Organization).
It was established in February 2004 to respond to the need to achieve a sustainability of the fisheries and to provide relevant, reliable and up-to-date information on a global scale.
FIRMS aims to provide information in order to develop effective fisheries policies in accordance with the Code of Conduct for Responsible Fisheries.
This code of conduct, adopted by FAO members on 31 October 1995, contains a broad set of principles and methods for developing and managing fisheries and aquaculture. A voluntary, non-binding instrument, the code is widely recognized as the global standard for settling out the aims of sustainable fisheries and aquaculture for the coming decades.
The information available in FIRMS is based on international protocols and data/metadata standards. It benefits also of functionalities from the Fisheries Global Information System (FIGIS) implemented by FAO.
The information is presented in synthesized fact sheets and state of resource summaries which include images, maps of geographical distribution, general biological and habitat characteristics, scientific assessment results, management considerations and status and trends statements.
Partners
Currently, the FIRMS partnership is composed of 13 international organizations:
Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR)
Commission for the Conservation of Southern Bluefin Tuna (CCSBT)
Statistical Office of the European Communities (EUROSTAT)
Fo |
https://en.wikipedia.org/wiki/Gunshot%20wound | A gunshot wound (GSW) is a penetrating injury caused by a projectile (e.g. a bullet) from a gun (typically firearm or air gun). Damages may include bleeding, bone fractures, organ damage, wound infection, loss of the ability to move part of the body, and in severe cases, death. Damage depends on the part of the body hit, the path the bullet follows through the body, and the type and speed of the bullet. Long-term complications can include bowel obstruction, failure to thrive, neurogenic bladder and paralysis, recurrent cardiorespiratory distress and pneumothorax, hypoxic brain injury leading to early dementia, amputations, chronic pain and pain with light touch (hyperalgesia), deep venous thrombosis with pulmonary embolus, limb swelling and debility, and lead poisoning.
Factors that determine rates of gun violence vary by country. These factors may include the illegal drug trade, easy access to firearms, substance misuse including alcohol, mental health problems, firearm laws, social attitudes, economic differences, and occupations such as being a police officer. Where guns are more common, altercations more often end in death.
Before management begins, the area must be verified as safe. This is followed by stopping major bleeding, then assessing and supporting the airway, breathing, and circulation. Firearm laws, particularly background checks and permit to purchase, decrease the risk of death from firearms. Safer firearm storage may decrease the risk of firearm-related deaths in children.
In 2015, about a million gunshot wounds occurred from interpersonal violence. In 2016, firearms resulted in 251,000 deaths globally, up from 209,000 in 1990. Of these deaths, 161,000 (64%) were the result of assault, 67,500 (27%) were the result of suicide, and 23,000 (9%) were accidents. In the United States, guns resulted in about 40,000 deaths in 2017. Firearm-related deaths are most common in males between the ages of 20 and 24 years. Economic costs due to gunshot wounds h |
https://en.wikipedia.org/wiki/Holm%E2%80%93Bonferroni%20method | In statistics, the Holm–Bonferroni method, also called the Holm method or Bonferroni–Holm method, is used to counteract the problem of multiple comparisons. It is intended to control the family-wise error rate (FWER) and offers a simple test uniformly more powerful than the Bonferroni correction. It is named after Sture Holm, who codified the method, and Carlo Emilio Bonferroni.
Motivation
When considering several hypotheses, the problem of multiplicity arises: the more hypotheses are checked, the higher the probability of obtaining Type I errors (false positives). The Holm–Bonferroni method is one of many approaches for controlling the FWER, i.e., the probability that one or more Type I errors will occur, by adjusting the rejection criteria for each of the individual hypotheses.
Formulation
The method is as follows:
Suppose you have p-values, sorted into order lowest-to-highest , and their corresponding hypotheses （null hypotheses). You want the FWER to be no higher than a certain pre-specified significance level .
Is ? If so, reject and continue to the next step, otherwise EXIT.
Is ? If so, reject also, and continue to the next step, otherwise EXIT.
And so on: for each P value, test whether . If so, reject and continue to examine the larger P values, otherwise EXIT.
This method ensures that the FWER is at most , in the strong sense.
Rationale
The simple Bonferroni correction rejects only null hypotheses with p-value less than , in order to ensure that the FWER, i.e., the risk of rejecting one or more true null hypotheses (i.e., of committing one or more type I errors) is at most . The cost of this protection against type I errors is an increased risk of failing to reject one or more false null hypotheses (i.e., of committing one or more type II errors).
The Holm–Bonferroni method also controls the FWER at , but with a lower increase of type II error risk than the classical Bonferroni method. The Holm–Bonferroni method sorts the p-values from lowest to |
https://en.wikipedia.org/wiki/Essential%20unified%20process | The essential unified process for software development, or EssUP, was invented by Ivar Jacobson as an improvement on the rational unified process. It identifies practices, such as use cases, iterative development, architecture driven development, team practices and process practices, which are borrowed from RUP, CMMI and agile development. The idea is that you can pick those practices that are applicable to your situation and combine them into your own process. This is considered an improvement with respect to RUP, because with RUP the practices are all intertwined and cannot be taken in isolation.
EssUP is supported by a set of playing cards, each card describing a practice. This is because Ivar Jacobson believes that people buy his books but few read them.
It is announced that EssUP will be supported both by the IBM Rational toolset, Eclipse and Microsoft's Visual Studio. |
https://en.wikipedia.org/wiki/Gelato%20Federation | The Gelato Federation (usually just Gelato) was a "global technical community dedicated to advancing Linux on the Intel Itanium platform through collaboration, education, and leadership." Formed in 2001, membership included more than seventy academic and research organizations around the world, including several that operated Itanium-based supercomputers on the Top500 list. The organization was active in projects to enhance the Linux kernel for Itanium and GCC for Itanium. The organization took its name from the Italian dessert gelato, paying homage to this by naming sub-projects Gelato Vanilla and Gelato Coconut for varieties of the dessert.
History
In late 2001, representatives from seven organizations met with Hewlett-Packard. The institutions were the Bioinformatics Institute, Singapore; Groupe ESIEE, France; Hewlett-Packard Company; National Center for Supercomputing Applications, USA; Tsinghua University, China; University of Illinois at Urbana-Champaign, USA; University of New South Wales, Australia; and University of Waterloo, Canada. These were the founding members of Gelato.
Representatives from these organizations met twice a year. The first few meetings (in Palo Alto, California 2001 and Paris 2002) were primarily a "strategy council meeting" where the by-laws and charter were hammered out.
The Sydney meeting in October 2002 was the first that included a day of technical presentations. These became a regular feature of the meetings, eventually expanded to conferences, and thus the two conferences each year were entirely composed of technical presentations by vendors and members.
The organization apparently ceased operation in 2009. The Itanium processor was discontinued by Intel in 2021.
Membership
The federation grew markedly after its inception. By April 2007, there were more than 70 members and sponsors around the world. Members were institutions, but there were a few individuals who, because of their contribution to IA-64 on Linux or to |
https://en.wikipedia.org/wiki/Recognition-by-components%20theory | The recognition-by-components theory, or RBC theory, is a process proposed by Irving Biederman in 1987 to explain object recognition. According to RBC theory, we are able to recognize objects by separating them into geons (the object's main component parts). Biederman suggested that geons are based on basic 3-dimensional shapes (cylinders, cones, etc.) that can be assembled in various arrangements to form a virtually unlimited number of objects.
Geons
The recognition-by-components theory suggests that there are fewer than 36 geons which are combined to create the objects we see in day-to-day life. For example, when looking at a mug we break it down into two components – "cylinder" and "handle". This also works for more complex objects, which in turn are made up of a larger number of geons. Perceived geons are then compared with objects in our stored memory to identify what it is we are looking at. The theory proposes that when we view objects we look for two important components.
Edges – This enables us to maintain the same perception of the object regardless of viewing orientation.
Concavities – The area where two edges meet. These enable us to observe the separation between two or more geons.
Analogy between speech and objects
In his proposal of RBC, Biederman makes an analogy to the composition of speech and objects that helps support his theory. The idea is that about 44 individual phonemes or "units of sound" are needed to make up every word in the English language, and only about 55 are needed to make up every word in all languages. Though small differences may exist between these phonemes, there is still a discrete number that make up all languages.
A similar system may be used to describe how objects are perceived. Biederman suggests that in the same way speech is made up by phonemes, objects are made up by geons, and as there are a great variance of phonemes, there is also a great variance of geons. It is more easily understood how 36 geons can compo |
https://en.wikipedia.org/wiki/Acrodysostosis | Acrodysostosis is a rare congenital malformation syndrome which involves shortening of the interphalangeal joints of the hands and feet, intellectual disability in approximately 90% of affected children, and peculiar facies. Other common abnormalities include short head (as measured front to back), small broad upturned nose with flat nasal bridge, protruding jaw, increased bone age, intrauterine growth retardation, juvenile arthritis and short stature. Further abnormalities of the skin, genitals, teeth, and skeleton may occur.
Other common abnormalities include short head (as measured front to back), small broad upturned nose with flat nasal bridge, protruding jaw, increased bone age, intrauterine growth retardation, juvenile arthritis and short stature. Further abnormalities of the skin, genitals, teeth, and skeleton may occur.
Signs and Symptoms
Acrodysostosis presents with a wide spectrum of clinical manifestations. The following is a list of conditions and complications associated with acrodysostosis.
Bone issues
Skeletal dysplasia (dwarfism, short stature)
Brachydactyly
Advanced bone age
Bone plate fusing
Scoliosis
Pain – joint, hip, lower back, wrist
Endocrine
Hypothyroidism
Hypoparathyroidism
Pseudohypoparathyroidism
Vitamin D deficiency
Thyroid cysts
Type 1 diabetes
Behavioural / Developmental / Emotional
Autism Spectrum Disorder (ASD)
Childhood Apraxia of Speech
Cognitive impairment
Sensory issues
Gross motor delays
Fine motor delays
Craniofacial and dental
Cranial frontal nasal syndrome Midface hypoplasia
Depressed nasal bridge
Retrognathia
Glossoptosis
High palate
Mandibular distraction surgery Jaw surgery
Underbite
Chalky teeth
Overcrowded teeth
Early eruption of adult teeth
Small, unaligned teeth
Cardiology
Hypertension
Atrial Septal Defect (ASD)
Aortic Coarctation
Middle Aortic Syndrome (MAS) Coarctation of abdominal aorta Bradycardia
Bicuspid aortic valve
Causes
Acrodysostos |
https://en.wikipedia.org/wiki/Eosinophilic%20gastroenteritis | Eosinophilic gastroenteritis (EG or EGE) is a rare and heterogeneous condition characterized by patchy or diffuse eosinophilic infiltration of gastrointestinal (GI) tissue, first described by Kaijser in 1937. Presentation may vary depending on location as well as depth and extent of bowel wall involvement and usually runs a chronic relapsing course. It can be classified into mucosal, muscular and serosal types based on the depth of involvement. Any part of the GI tract can be affected, and isolated biliary tract involvement has also been reported.
The stomach is the organ most commonly affected, followed by the small intestine and the colon.
Signs and symptoms
EG typically presents with a combination of chronic nonspecific GI symptoms which include abdominal pain, diarrhea, occasional nausea and vomiting, weight loss and abdominal distension. Approximately 80% have symptoms for several years; a high degree of clinical suspicion is often required to establish the diagnosis, as the disease is extremely rare. It doesn't come all of a sudden but takes about 3–4 years to develop depending upon the age of the patient. Occasionally, the disease may manifest itself as an acute abdomen or bowel obstruction.
Mucosal EG (25–100%) is the most common variety, which presents with features of malabsorption and protein losing enteropathy. Failure to thrive and anaemia may also be present. Lower gastrointestinal bleeding may imply colonic involvement.
Muscular EG (13–70%) present with obstruction of gastric outlet or small intestine; sometimes as an obstructing caecal mass or intussusception.
Subserosal EG (4.5% to 9% in Japan and 13% in the US) presents with ascites which is usually exudative in nature, abundant peripheral eosinophilia, and has favourable responses to corticosteroids.
Other documented features are cholangitis, pancreatitis, eosinophilic splenitis, acute appendicitis and giant refractory duodenal ulcer.
Pathophysiology
Peripheral blood eosinophilia and eleva |
https://en.wikipedia.org/wiki/Antistatic%20bag | An antistatic bag is a bag used for storing electronic components, which are prone to damage caused by electrostatic discharge (ESD).
These bags are usually plastic polyethylene terephthalate (PET) and have a distinctive color (silvery for metallised film, pink or black for polyethylene). The polyethylene variant may also take the form of foam or bubble wrap, either as sheets or bags. Multiple layers of protection are often used to protect from both mechanical damage and electrostatic damage. A protected device can be packaged inside a metalized PET film bag, inside a pink polyethylene bubble-wrap bag, which is finally packed inside a rigid black polyethylene box lined with pink poly foam. It is important that the bags only be opened at static-free workstations.
Dissipative antistatic bags, as the name suggests, are made of standard polyethylene with a static dissipative coating or layer on the plastic. This prevents buildup of a static charge on the surface of the bag, as it dissipates the charge to ground (i.e., whatever other surface it is touching). This bridge to ground is achieved with the inclusion of a tallow amine on the bags surface which attracts moisture that can conduct the charge to another surface, or to the atmosphere itself. In this sense, this type is truly 'antistatic' in that it hinders the formation of static charges. It, however, is not resistant to electrostatic discharge; if something else with a charge touches the bag (such as a person's hand), its charge would easily transfer through the bag and its contents. These bags are usually pink or red in color because of the dissipative chemical layer. Black bags also exist, wherein the polyethylene is manufactured containing trace amounts of carbon, forming a partial shield, though not a complete one.
Conductive antistatic bags are manufactured with a layer of conductive metal, often aluminum, and a dielectric layer of plastic covered in a static dissipative coating. This forms both a shield an |
https://en.wikipedia.org/wiki/Peliosis%20hepatis | Peliosis hepatis is an uncommon vascular condition characterised by multiple, randomly distributed, blood-filled cavities throughout the liver. The size of the cavities usually ranges between a few millimetres and 3 cm in diameter. In the past, it was a mere histological curiosity occasionally found at autopsies, but has been increasingly recognised with wide-ranging conditions from AIDS to the use of anabolic steroids. It also occasionally affects spleen, lymph nodes, lungs, kidneys, adrenal glands, bone marrow, and other parts of gastrointestinal tract.
Peliosis hepatis is often erroneously written "peliosis hepatitis", despite its not being one of the hepatitides. The correct term arises from the Greek pelios, i.e. discoloured by extravasated blood, livid, and the Latinized genitive case (hepatis) of the Greek hepar, liver.
Signs and symptoms
Often, peliosis hepatis causes no symptoms (asymptomatic). In other cases, it may be identified after blood tests show abnormalities in liver enzymes.
Less commonly, peliosis hepatis may cause abdominal pain, especially right upper quadrant pain, or jaundice.
Presentation
Disease associations
Infections: HIV, bacillary peliosis (caused by genus Bartonella, bacteria responsible for cat-scratch disease which are identified histologically adjacent to the peliotic lesions), Staphylococcus aureus
Chronic conditions: End stage kidney failure, kwashiorkor, tuberculosis, and other chronic infections
Malignancy: Monoclonal gammopathies (multiple myeloma and Waldenström's macroglobulinemia), Hodgkin disease, malignant histiocytosis, seminoma, hepatocellular adenoma, and hepatocarcinoma
Kidney transplants: It can be found in up to 20% patients, can be related to azathioprine or cyclosporine use, and may be associated with increased risk of transplant rejection.
Drugs and toxins: Corticosteroids, androgens, azathioprine, tamoxifen
Pathophysiology
The pathogenesis of peliosis hepatis is unknown. Several hypotheses are |
https://en.wikipedia.org/wiki/Phenylalanine%20racemase%20%28ATP-hydrolysing%29 | The enzyme phenylalanine racemase (, phenylalanine racemase, phenylalanine racemase (adenosine triphosphate-hydrolysing), gramicidin S synthetase I) is the enzyme that acts on amino acids and derivatives. It activates both the L & D stereo isomers of phenylalanine to form L-phenylalanyl adenylate and D-phenylalanyl adenylate, which are bound to the enzyme. These bound compounds are then transferred to the thiol group of the enzyme followed by conversion of its configuration, the D-isomer being the more favorable configuration of the two, with a 7 to 3 ratio between the two isomers. The racemisation reaction of phenylalanine is coupled with the highly favorable hydrolysis of adenosine triphosphate (ATP) to adenosine monophosphate (AMP) and pyrophosphate (PP), thermodynamically allowing it to proceed. This reaction is then drawn forward by further hydrolyzing PP to inorganic phosphate (Pi), via Le Chatelier's principle.
Other names
phenylalanine racemase
phenylalanine racemase (adenosine triphosphate-hydrolysing)
gramicidin S synthetase I
Pathway
Phenylalanine Metabolism
Substrate
L – Phenylalanine
Product
D - Phenylalanine
Cofactor
Pyridoxal-phosphate (active form of vitamin B6)
Links to disease
Problems in the digestion of phenylalanine (phe) to tyrosine (tyr) lead to the buildup of both phe and phenylpyruvate, in a disease called Phenylketonuria (PKU). These two compounds build up in the blood stream and cerebral spinal fluid, which can lead to mental retardation if left untreated. Treatment consists of a restricted diet of foods that contain phe or compounds that can breakdown into phe. Children in the US are routinely tested for this at birth. For more information see the Phenylketonuria page or the link below.
Quick facts
pH Range = 7.2 – 8.6
Equilibrium Ratio:L-Phe:D-Phe = 3:7
Specific Activity: 0.019
The reaction
|}
See also
Phenylalanine
Racemase
Phenylketonuria |
https://en.wikipedia.org/wiki/Central%20Equipment%20Identity%20Register | A Central Equipment Identity Register (CEIR) is a database of mobile equipment identifiers (IMEI – for networks of GSM standard, MEID – for networks of CDMA standard). Such an identifier is assigned to each SIM slot of the mobile device.
Lists of IMEIs may be the:
White – for devices that are allowed to register in the cellular network,
Black – for devices that are prohibited to register in the cellular network,
Grey – for devices in intermediate status (when it is not yet defined in which of the lists - black or white - the device should be placed).
Depending on the rules of mobile equipment registration in a country the CEIR database may contain other lists or fields beside IMEI. For example, the subscriber number (MSISDN), which is bound to the IMEI, the ID of the individual (passport data, National ID, etc.) who registered IMEI in the database, details of the importer who brought the device into the country, etc.
Originally abbreviation CEIR stood for IMEI Database, created and provided by GSM Association. It was proposed to blacklist the IMEIs of stolen or lost phones. It was assumed that any MNO would be able to receive this list to block the registration of such devices on their network. Thus, it turns out that a stolen phone, once blacklisted by the GSMA CEIR, cannot be used on a large number of cellular networks, which means that the theft of mobile devices will become meaningless. However, it soon became clear that the MNOs on their initiative were not going to do this because if many phones stopped working in their networks, but works in another, it puts them at a disadvantage and can lead to an outflow of subscribers. It became clear that the blocking of stolen devices should be introduced simultaneously in all mobile networks of the country by legislative measures at the initiative of the communications regulator. In this case, as a rule, a national IMEI database is created, which contains general lists of blocked IMEIs. Since the registration in |
https://en.wikipedia.org/wiki/Nettime | Nettime is an internet mailing list proposed in 1995 by Geert Lovink and Pit Schultz (then half-jokingly called "the nettime brothers") at the second meeting of the "Medien Zentral Kommittee" during the Venice Biennale. Since 1998, Ted Byfield and Felix Stalder have moderated the main list, coordinated moderation of other lists in the nettime "family," and maintained the site as their nexus.
The name nettime was chosen as a statement against space metaphors such as cyberspace, dominant at the time.
The time of nettime is a social time, it is subjective and intensive, with condensation and extractions, segmented by social events like conferences and little meetings, and text gatherings for export into the paper world. Most people still like to read a text printed on wooden paper, more than transmitted via waves of light. Nettime is not the same time like geotime, or the time clocks go. Everyone who programs or often sits in front of a screen knows about the phenomena of being out of time, time on the net consists of different speeds, computers, humans, software, bandwidth, the only way to see a continuity of time on the net is to see it as a asynchronous network of synchronized time zones.
Nettime has been widely recognized for its seminal role stimulating and disseminating ideas about Netzkritik or Net Critique, net.art, and tactical media and pioneered practices such as "collaborative filtering". For example, in 2004 nettime was nominated for an Ars Electronica Golden Nica award. However, the moderators refuse to speak or act as representatives of an organization, preferring instead to serve inasmuch as possible as coordinators of a loose or "headless" collective.
The list and related meetings were a strong influence on Bruce Sterling's 1996 science fiction novel Holy Fire.
Initially, it was both part of an early wave of, and served as an inspiration for, a number of related efforts such as Blast (1995–1998), Rhizome (1996–present), Fibreculture (2001–present), |
https://en.wikipedia.org/wiki/Fatou%27s%20theorem | In mathematics, specifically in complex analysis, Fatou's theorem, named after Pierre Fatou, is a statement concerning holomorphic functions on the unit disk and their pointwise extension to the boundary of the disk.
Motivation and statement of theorem
If we have a holomorphic function defined on the open unit disk , it is reasonable to ask under what conditions we can extend this function to the boundary of the unit disk. To do this, we can look at what the function looks like on each circle inside the disk centered at 0, each with some radius . This defines a new function:
where
is the unit circle. Then it would be expected that the values of the extension of onto the circle should be the limit of these functions, and so the question reduces to determining when converges, and in what sense, as , and how well defined is this limit. In particular, if the norms of these are well behaved, we have an answer:
Theorem. Let be a holomorphic function such that
where are defined as above. Then converges to some function pointwise almost everywhere and in norm. That is,
Now, notice that this pointwise limit is a radial limit. That is, the limit being taken is along a straight line from the center of the disk to the boundary of the circle, and the statement above hence says that
The natural question is, with this boundary function defined, will we converge pointwise to this function by taking a limit in any other way? That is, suppose instead of following a straight line to the boundary, we follow an arbitrary curve converging to some point on the boundary. Will converge to ? (Note that the above theorem is just the special case of ). It turns out that the curve needs to be non-tangential, meaning that the curve does not approach its target on the boundary in a way that makes it tangent to the boundary of the circle. In other words, the range of must be contained in a wedge emanating from the limit point. We summarize as follows:
Definition. Let |
https://en.wikipedia.org/wiki/Sex%20pheromone | Sex pheromones are pheromones released by an organism to attract an individual of the same species, encourage them to mate with them, or perform some other function closely related with sexual reproduction.
Sex pheromones specifically focus on indicating females for breeding, attracting the opposite sex, and conveying information on species, age, sex and genotype. Non-volatile pheromones, or cuticular contact pheromones, are more closely related to social insects as they are usually detected by direct contact with chemoreceptors on the antennae or feet of insects.
Insect sex pheromones have found uses in monitoring and trapping of pest insects.
Evolution
Sex pheromones have evolved in many species. The many types of pheromones (i.e. alarm, aggregation, defense, sexual attraction) all have a common cause acting as chemical cues to trigger a response. However, sex pheromones are particularly associated with signaling mating behaviors or dominance. The odors released can be seen as a favorable trait selected by either the male or female leading to attraction and copulation. Chemical signaling is also used to find genetically different mates and thus avoid inbreeding. Females are often selective when deciding to mate, and chemical communication ensures that they find a high-quality mate that satisfies their reproductive needs.
Sexual selection
Odours may be a kind of male "ornament" selected for by female choice. They meet the criteria for such ornaments that Charles Darwin set out in The Descent of Man, and Selection in Relation to Sex. After many years of study the importance of such chemical communication is becoming clear.
Males usually compete for scarce females, which make adaptive choices based on male traits. The choice can benefit the female directly and/or genetically. In tiger moths (Utetheisa ornatrix), females choose the males that produce the most pheromone; an honest signal of the amount of protective alkaloids the male has, as well as an indicator |
https://en.wikipedia.org/wiki/Trace%20monoid | In computer science, a trace is a set of strings, wherein certain letters in the string are allowed to commute, but others are not. It generalizes the concept of a string, by not forcing the letters to always be in a fixed order, but allowing certain reshufflings to take place. Traces were introduced by Pierre Cartier and Dominique Foata in 1969 to give a combinatorial proof of MacMahon's master theorem. Traces are used in theories of concurrent computation, where commuting letters stand for portions of a job that can execute independently of one another, while non-commuting letters stand for locks, synchronization points or thread joins.
The trace monoid or free partially commutative monoid is a monoid of traces. In a nutshell, it is constructed as follows: sets of commuting letters are given by an independency relation. These induce an equivalence relation of equivalent strings; the elements of the equivalence classes are the traces. The equivalence relation then partitions up the free monoid (the set of all strings of finite length) into a set of equivalence classes; the result is still a monoid; it is a quotient monoid and is called the trace monoid. The trace monoid is universal, in that all dependency-homomorphic (see below) monoids are in fact isomorphic.
Trace monoids are commonly used to model concurrent computation, forming the foundation for process calculi. They are the object of study in trace theory. The utility of trace monoids comes from the fact that they are isomorphic to the monoid of dependency graphs; thus allowing algebraic techniques to be applied to graphs, and vice versa. They are also isomorphic to history monoids, which model the history of computation of individual processes in the context of all scheduled processes on one or more computers.
Trace
Let denote the free monoid, that is, the set of all strings written in the alphabet . Here, the asterisk denotes, as usual, the Kleene star. An independency relation on then induces a ( |
https://en.wikipedia.org/wiki/Orthopedic%20pathology | Orthopedic pathology, also known as bone pathology is a subspecialty of surgical pathology which deals with the diagnosis and feature of many bone diseases, specifically studying the cause and effects of disorders of the musculoskeletal system. It uses gross and microscopic findings along with the findings of in vivo radiological studies, and occasionally, specimen radiographs to diagnose diseases of the bones.
Causes and effects
Orthopaedic disorders may be congenital and there may be hereditary and environmental factors that can affect the normal functioning of the bones, joints, or muscles. Other causes of bone diseases include severe impacts/injuries and weakness in bones/bone loss.
The effects of bone disorders will vary with disease. The effects can occur physically, mentally and financially as well as impact the individuals quality of life. Orthopaedic disorders can drastically affect an individual's functional ability. Individuals who have had bone diseases can experience complications such as extreme pain, fractures, height loss and the ability to be mobile. They can also be more susceptible to other issues, for example, a urinary tract infection (UTI) or pneumonia. Many of these bone disorders could lead to declines in both mental and physical health. In addition to a physical impact, bone disorders can also give rise to psychological ramifications and reflect negatively on an individual's mindset, body image as well as self-esteem, which may result in the individual feeling helpless and yield fears of falling.
To care for bone diseases and disorders is quite expensive. These costs can include both direct and indirect medical expenses as well as possible job loss or productivity loss for the patient. The chances of death vary enormously between the bone disorders due to the differing degree of severity, however many bone diseases do increase an individual's susceptibility to other complications. These disorders depend on multiple factors such as geneti |
https://en.wikipedia.org/wiki/Opengear | Opengear is a global computer network technology company headquartered in Edison, New Jersey, U.S., with R&D operations in Brisbane, Qld, Australia and production in Sandy, UT.
The company develops and manufactures "smart out-of-band infrastructure management" products aimed at allowing customers to securely access, control and automatically troubleshoot and repair their IT infrastructure remotely, including network and data-center management, for resilient operation.
Opengear solutions provide always-available wired and wireless secure remote access, with failover capabilities to automatically restore site connectivity. This enables technical staff to provision, maintain and repair infrastructure from anywhere at any time, as if they were physically present, thereby enabling both the operational costs and the risk of downtime to be reduced.
In December 2019, Opengear was acquired by Digi International.
Products
Opengear's management products include IM7200 advanced console servers that streamline management of network, server, and power infrastructure in data centers and colocation facilities; and ACM7000 remote management gateways that deliver secure remote monitoring, access and control of distributed networks and remote sites. The Lighthouse Centralized Management platform then provides a single point of scalable, secure management for these Opengear appliances and connected devices. The Opengear NetOps Console Server combine out-of-band management and NetOps tools in a single appliance, minimizing human intervention and simplifying repetitive tasks.
All Opengear products provide a secure alternate out-of-band path to the managed infrastructure, enabling accessibility even during system or network outage. They monitor, access, and control all critical infrastructure at all local and remote sites, from applications, computers and networking equipment, to security cameras, power supplies and door sensors - to proactively detect faults and remediate before t |
https://en.wikipedia.org/wiki/Soft%20tissue%20pathology | Soft tissue pathology is the subspecialty of surgical pathology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of the soft tissues, such as muscle, adipose tissue, tendons, fascia, and connective tissues. Many malignancies of the soft tissues are challenging for the pathologist to diagnose through gross examination and microscopy alone, and additional tools such as immunohistochemistry, electron microscopy, and molecular pathology techniques are sometimes employed to obtain a definitive diagnosis. |
https://en.wikipedia.org/wiki/Pulmonary%20pathology | Pulmonary pathology is the subspecialty of surgical pathology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of the lungs and thoracic pleura. Diagnostic specimens are often obtained via bronchoscopic transbronchial biopsy, CT-guided percutaneous biopsy, or video-assisted thoracic surgery (VATS). The diagnosis of inflammatory or fibrotic diseases of the lungs is considered by many pathologists to be particularly challenging.
Anatomical pathology |
https://en.wikipedia.org/wiki/Renal%20pathology | Renal pathology is a subspecialty of anatomic pathology that deals with the diagnosis and characterization of medical diseases (non-tumor) of the kidneys. In the academic setting, renal pathologists work closely with nephrologists and transplant surgeons, who typically obtain diagnostic specimens via percutaneous renal biopsy. The renal pathologist must synthesize findings from light microscopy, electron microscopy, and immunofluorescence to obtain a definitive diagnosis. Medical renal diseases may affect the glomerulus, the tubules and interstitium, the vessels, or a combination of these compartments.
External links
http://www.renalpathsoc.org/
Renal Pathology Tutorial written by J. Charles Jennette
Pathologist Guide
Anatomical pathology |
https://en.wikipedia.org/wiki/Digyny | Digyny (also digynia) refers to the process of a diploid ovum becoming fertilized by a haploid sperm. The result of digyny is a triploid zygote. In humans, both gametes (ovum and sperm) are normally haploid and give rise to a diploid zygote.
Digyny results in gestational abnormalities in humans, including an abnormally small placenta and a very growth-restricted fetus. As a result, the majority of triploid pregnancies are spontaneously aborted. The incidence rate of a live-born triploid human is approximately 1 in 50,000.
See also
Polyploidy
Triploid syndrome |
https://en.wikipedia.org/wiki/Tutti%20frutti | Tutti frutti (from Italian tutti i frutti, "all fruits"; also hyphenated tutti-frutti) is a colorful confectionery containing various chopped and usually candied fruits, or an artificial or natural flavouring simulating the combined flavour of many different fruits and vanilla. It is a popular ice cream flavour in Western countries outside of Italy.
Fruits used for tutti frutti ice cream include cherries, watermelon, raisins, and pineapple, often augmented with nuts. In the Netherlands, tutti-frutti (also "tutti frutti", "tuttifrutti") is a compote of dried fruits, served as a dessert or a side dish to a meat course. In Belgium, tutti-frutti is often seen as a dessert. Typically, it contains a combination of raisins, currants, apricots, prunes, dates, and figs.
In the United States, tutti frutti can also refer to fruits soaked in brandy or other spirits, or even to fruit fermented in a liquid containing sugar and yeast.
In Luxembourg, tutti fruitty refers to fruit salad, mainly pre-packaged, canned fruit salad from the supermarket.
History
Tutti frutti ice cream has been served for at least 160 years, as it appeared on the bill of fare for an 1860 dinner in England.
Recipes for tutti frutti ice cream were found in cookbooks of the late 19th century. A tutti frutti ice cream recipe was included in the 1874 cookbook Common Sense in the Household: A Manual of Practical Housewifery This recipe calls for actual tutti frutti and is not fancifully named. In the 1883 cookbook The Chicago Herald Cooking School there is also a tutti frutti ice cream recipe.
In 1888, one of the first gum flavors to be sold in a vending machine, created by the Adams New York Gum Company, was tutti frutti.
Many restaurant menus circa 1900 in the collection of the New York Public Library also list this variety of ice cream.
At least one early-20th-century American cookbook contains a suggestion that tutti frutti ice cream was popular in the United States. The Italian Cookbook contains a r |
https://en.wikipedia.org/wiki/Gastrointestinal%20pathology | Gastrointestinal pathology is the subspecialty of surgical pathology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of the digestive tract and accessory organs, such as the pancreas and liver.
Sub-specialty recognition and Board Certification
Gastrointestinal pathology (including liver, gallbladder and pancreas) is a recognized sub-specialty discipline of surgical pathology. Recognition of a sub-specialty is generally related to dedicated fellowship training offered within the subspecialty or, alternatively, to surgical pathologists with a special interest and extensive experience in gastrointestinal pathology. There are approximately 30 gastrointestinal pathology fellowships offered within the United States (predominantly academic, and more recently three "corporate" fellowships). This translates to fewer than 40 fellowship trained gastrointestinal pathologists being trained annually in the United States each year.
Fellowship in gastrointestinal pathology involves:
diagnostic evaluation of surgical (whole organ) and biopsy pathology of gastrointestinal tissue, [with the exception of at least one corporate fellowship]
consistent interaction with clinical colleagues (gastroenterologists, colorectal surgeons and gastrointestinal radiologists) to ensure understanding of the clinical aspects of gastrointestinal disease, treatment modalities and other diagnostic findings;
research in gastrointestinal physiology, disease mechanisms and histomorphology
education of general pathologists and clinical colleagues.
During the course of a one-year gastrointestinal pathology fellowship, the GI-liver pathology fellow will review between 8,000 and 15,000 gastrointestinal and liver biopsy and surgical specimens with all clinical history, laboratory data and frequently, knowledge of response to treatment. This volume of cases is similar to approximately five years of case experience for general surgical pathologists in pri |
https://en.wikipedia.org/wiki/Ophthalmic%20pathology | Ophthalmic pathology is the subspecialty of surgical pathology and also a subspecialty of ophthalmology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of the eyes. Ophthalmic pathologists generally work closely with ophthalmologists. |
https://en.wikipedia.org/wiki/Pediatric%20pathology | Pediatric pathology is the sub-specialty of surgical pathology which deals with the diagnosis and characterization of neoplastic and non-neoplastic diseases of children. The duties of pediatric pathologists can be divided into two categories: the examination of tissue samples, and the performing autopsies and placental examinations. |
https://en.wikipedia.org/wiki/Adenosine%20diphosphate%20ribose | Adenosine diphosphate ribose (ADPR) is an ester molecule formed into chains by the enzyme poly ADP ribose polymerase. ADPR is created from cyclic ADP-ribose (cADPR) by the CD38 enzyme using nicotinamide adenine dinucleotide (NAD+) as a cofactor.
ADPR binds to and activates the TRPM2 ion channel. ADPR is the most potent agonist of the TRPM2 channel. cADPR also binds to TPRM2, and the action of both molecules is synergistic, with both molecules enhancing the action of the other molecule in activating the TRPM2 channel.
See also
Adenosine diphosphate
ADP-ribosylation
Ribose
Poly (ADP-ribose) polymerase |
https://en.wikipedia.org/wiki/Gross%20processing | Gross processing, "grossing" or "gross pathology" is the process by which pathology specimens undergo examination with the bare eye to obtain diagnostic information, as well as cutting and tissue sampling in order to prepare material for subsequent microscopic examination.
Responsibility
Gross examination of surgical specimens is typically performed by a pathologist, or by a pathologists' assistant working within a pathology practice. Individuals trained in these fields are often able to gather diagnostically critical information in this stage of processing, including the stage and margin status of surgically removed tumors.
Steps
The initial step in any examination of a clinical specimen is confirmation of the identity of the patient and the anatomical site from which the specimen was obtained. Sufficient clinical data should be communicated by the clinical team to the pathology team in order to guide the appropriate diagnostic examination and interpretation of the specimen - if such information is not provided, it must be obtained by the examiner prior to processing the specimen.
There are usually two end products of the gross processing of a surgical specimen. The first is the gross description, a document which serves as the written record of the examiner's findings, and is included in the final pathology report. The second product is a set of tissue blocks, typically postage stamp-sized portions of tissue sealed in plastic cassettes, which will be processed into slides for microscopic examination. Since only a minority of the tissue from a large specimen can reasonably be subject to microscopic examination, the success of the final histological diagnosis is highly dependent on the skill of the professional performing the gross examination. The gross examiner may sample portions of the specimen for other types of ancillary tests as diagnostically indicated; these include microbiological culture, flow cytometry, cytogenetics, or electron microscopy.
Perpendi |
https://en.wikipedia.org/wiki/Adobe%20Media%20Player | Adobe Media Player is a discontinued desktop media player that allowed users to manage and interact with their media content, and allowed content publishers to define branding and advertising in and around their content. The Adobe Media Player was one of the first Adobe AIR applications from Adobe Systems. It was announced at NAB show in Las Vegas and was released in April 2008. It used DRM and enforces advertisement viewing, when watching videos both online and offline.
The player was designed to allow users to subscribe to webcasts from various providers to be either streamed or download for viewing offline. Adobe had signed CBS, PBS, MTV Networks, Universal Music Group, CondeNet, and Scripps Networks as partners. Adobe had planned to release other features to support various business models, such as the ability to rent videos.
Adobe Media Player was discontinued on 16 September 2010.
The player had been praised for its user-friendliness and compared to the internet TV service Joost.
See also
Open Source Media Framework (OSMF) |
https://en.wikipedia.org/wiki/Ethnoherpetology | Ethnoherpetology is the study of the past and present interrelationships between human cultures and reptiles and amphibians. It is a sub-field of ethnozoology, which in turn is a sub-field of ethnobiology.
Snakes and amphibians have been considered chthonic creatures in many cultures. Richly represented in mythology, culture, art, and literature, they often evoke revulsion, fear, suspicion and awe, sometimes even hysteria. Frogs and toads were believed to announce the rains with their choruses.
See also
Colorado River toad
Frogs in culture
Herpetology
Legendary salamander in popular culture
Nāga
Serpent (symbolism)
Bibliography
Bulmer, Ralph N.H. and Michael Tyler. 1968. Karam classification of frogs. Journal of the Polynesian Society 77(4): 621–639.
Indraneil Das – The Serpent's Tongue: A contribution to the ethnoherpetology of India and adjacent countries (Frankfurt am Main: Edition Chimaira, 1998)
Walsh, M.T. – Snakes and Other Reptiles in Mtanga: preliminary notes on ethnoherpetology in a village bordering Gombe Stream National Park, western Tanzania. (1997)
Bertrand, H. – Contribution à l'étude de l'herpétologie et de l'ethnoherpétologie en Anjou (A study on the herpetology and ethnoherpetology of Anjou province)
Lee, J. C. – Ethnoherpetology in the Yucatán Peninsula. In Amphibians and Reptiles of the Yucatán Peninsula, by J. C. Lee. Ithaca, NY: Cornell University Press, 1996.
An example of indigenous ethnoherpetological knowledge – notes written by a Bukusu-speaking research assistant from western Kenya:
Wepukhulu, D. M. 1992. Bukusu Ethnozoology (Reptiles and Amphibians). Unpublished manuscript notes on Bukusu ethnozoology.
Ethnobiology
Herpetology |
https://en.wikipedia.org/wiki/Cray%20X2 | The Cray X2 is a vector processing node for the Cray XT5h supercomputer, developed and sold by Cray Inc. and launched in 2007.
The X2, developed under the code name Black Widow, was originally expected to be a standalone supercomputer system, superseding the Cray X1 parallel vector supercomputer. However, the X2 was eventually launched as one of the four processor "blade" options for the XT5h system.
An X2 blade comprises two nodes, each with four symmetric multiprocessing vector processors and 32 or 64 GB of shared memory. Each node has a peak performance of more than 100 gigaflops. X2 processors are connected using a radix-64 "fat-tree" interconnect implemented by the YARC router ASIC. X2 blades also link into the XT5h system via its SeaStar2+ processor interconnect.
Up to 256 X2 blades can be installed in an XT5h system. The X2 processor nodes integrate with the Cray XT5h's UNICOS/lc OS, user environment, and storage subsystem, as part of the Rainier project.
External links
Cray XT5h Supercomputer
Cray Introduces Next-Generation Supercomputers
Thinking Ahead: Future Architectures from Cray
The BlackWidow High-Radix Clos Network
Cray X2 Vector Processing Blade
X2
Vector supercomputers |
https://en.wikipedia.org/wiki/Food%20testing%20strips | Food testing strips are products that help determine whether or not food contains bacteria that can cause foodborne illness. These products can typically be used on food, water, and hard surfaces, and are often designed for quick and easy home and commercial use.
Categories
Currently, there are two categories of food testing strips on the market.
One type of food testing strip is an assay enzyme reactant test, which requires the strip to be dipped into a blended mixture of food or test samples, distilled water and a reagent. Such tests are designed specifically to detect those strains of E.coli and Salmonella that are harmful to humans.
A second type of food testing strip is a gram-negative swab, which is usually administered directly to the food itself. Gram-negative swabs generally work faster than enzyme reactant strips, but they differ in that the gram-negative swabs are designed to detect a broad group of organisms, not just those that can cause foodborne illness in humans.
Usage
The enzyme reactant test strips react when the buffer solution breaks the bacterial wall. This breach releases enzymes, which react upon contact to the enzyme test strips.
The gram-negative reactant activates when components of the gram-negative cell wall or specific enzymes are present, causing the swab itself to change color. This is not directly indicative of the presence or absence of human pathogen in the test sample.
People are now working on new ways to enhance these pathogen strips with silk pills and new nano-fiber technology. |
https://en.wikipedia.org/wiki/Max%20Planck%20Institute%20of%20Molecular%20Plant%20Physiology | The Max Planck Institute of Molecular Plant Physiology () is a German research institute for molecular plant physiology, based in the Golm district of Potsdam, Brandenburg. Founded on 1 January 1994, the MPIMP focuses on the study of the dynamics of plant metabolism and how that relates to the entire plant system. The institution is one of the 80 institutes in the Max Planck Society (Max-Planck-Gesellschaft).
Research
The MPIP's mission is to study the dynamics of plant metabolism in the context of the plant system as a whole. Since this system is more than a collection of genes and gene products, they focus our efforts on understanding how the individual components dynamically interact over time and under different conditions. By combining traditional biological approaches with techniques relevant to functional genomics, the institute is forming a holistic view of the structure, function, dynamics, and regulation of entire plant genomes, proteomes, and metabolomes.
Organization
About 360 people, including students, work at the MPIMP. Currently there are people from more than 30 nations working at the institute. More than half of the employees are female. The institute has three directors, namely, Caroline Gutjahr, Claudia Köhler and Ralph Bock, all leading a specific research department.
Board of trustees
Alongside the dedicated scientists working within its walls, prominent individuals from industrial, financial, political and cultural circles form its Board of Trustees to strengthen and support the links between our institute and the greater community. The mentioned board overseas the affairs of MPIMP as well as neighboring Max Planck Institute for Colloids and Interfaces also based in Golm. As of February 2014, the following are the members of the Board of Trustees:
Ulrich Buller - Senior Vice President Research Planning, Fraunhofer Gesellschaft
Rolf Emmermann - Vice-chairman of the Board of Trustees, GeoForschungsZentrum Potsdam (GFZ)
Detlev Ganten - Chai |
https://en.wikipedia.org/wiki/Lazy%20learning | In machine learning, lazy learning is a learning method in which generalization of the training data is, in theory, delayed until a query is made to the system, as opposed to eager learning, where the system tries to generalize the training data before receiving queries.
The primary motivation for employing lazy learning, as in the K-nearest neighbors algorithm, used by online recommendation systems ("people who viewed/purchased/listened to this movie/item/tune also ...") is that the data set is continuously updated with new entries (e.g., new items for sale at Amazon, new movies to view at Netflix, new clips at YouTube, new music at Spotify or Pandora). Because of the continuous update, the "training data" would be rendered obsolete in a relatively short time especially in areas like books and movies, where new best-sellers or hit movies/music are published/released continuously. Therefore, one cannot really talk of a "training phase".
Lazy classifiers are most useful for large, continuously changing datasets with few attributes that are commonly queried. Specifically, even if a large set of attributes exist - for example, books have a year of publication, author/s, publisher, title, edition, ISBN, selling price, etc. - recommendation queries rely on far fewer attributes - e.g., purchase or viewing co-occurrence data, and user ratings of items purchased/viewed.
Advantages
The main advantage gained in employing a lazy learning method is that the target function will be approximated locally, such as in the k-nearest neighbor algorithm. Because the target function is approximated locally for each query to the system, lazy learning systems can simultaneously solve multiple problems and deal successfully with changes in the problem domain. At the same time they can reuse a lot of theoretical and applied results from linear regression modelling (notably PRESS statistic) and control. It is said that the advantage of this system is achieved if the predictions using a s |
https://en.wikipedia.org/wiki/Eager%20learning | In artificial intelligence, eager learning is a learning method in which the system tries to construct a general, input-independent target function during training of the system, as opposed to lazy learning, where generalization beyond the training data is delayed until a query is made to the system.
The main advantage gained in employing an eager learning method, such as an artificial neural network, is that the target function will be approximated globally during training, thus requiring much less space than using a lazy learning system. Eager learning systems also deal much better with noise in the training data. Eager learning is an example of offline learning, in which post-training queries to the system have no effect on the system itself, and thus the same query to the system will always produce the same result.
The main disadvantage with eager learning is that it is generally unable to provide good local approximations in the target function. |
https://en.wikipedia.org/wiki/Offline%20learning | In machine learning, systems which employ offline learning do not change their approximation of the target function when the initial training phase has been completed. These systems are also typically examples of eager learning.
While in online learning, only the set of possible elements is known, in offline learning, the identity of the elements as well as the order in which they are presented is known to the learner.
Applications for robotics control
The ability of robots to learn is equal to create a table (information) which is filled with values. One option for doing so is programming by demonstration. Here, the table is filled with values by a human teacher. The demonstration is provided either as direct numerical control policy which is equal to a trajectory, or as an indirect objective function which is given in advance.
Offline learning is working in batch mode. In step 1 the task is demonstrated and stored in the table, and in step 2 the task is reproduced by the robot. The pipeline is slow and inefficient because a delay is there between behavior demonstration and skill replay.
A short example will help to understand the idea. Suppose the robot should learn a wall following task and the internal table of the robot is empty. Before the robot gets activated in the replay mode, the human demonstrator has to teach the behavior. He is controlling the robot with teleoperation and during the learning step the skill table is generated. The process is called offline, because the robot control software is doing nothing but the device is utilized by the human operator as a pointing device for driving along the wall.
See also
Online learning, the opposite model
Incremental learning, a learning model for the incremental extension of knowledge |
https://en.wikipedia.org/wiki/Bulk%20email%20software | Bulk email software is software that is used to send emails in large quantities.
Bulk email software usually refers to standalone software, while there are bulk email-sending web-based services.
Types of software
Most bulk email software programs are hosted by third-party companies that sell access to their system. Customers pay per send or at a fixed monthly rate to have their own user account from which they can manage their contacts and send out email campaigns. Generally the advantage of this type of program is the reliability of the third party vendor and their application.
Some bulk email software programs are self-hosted. The customer buys a license or develops his own program and then hosts the program. Generally the advantage of this type of program is the lack of ongoing monthly fees for the owner/developer of the program. The disadvantage of using this option is that the delivery rate is reduced as users frequently use one server to send bulk emails. There are various settings to tweak to avoid a server being labelled as spam.
These bulk email service providers help marketers conduct email marketing. These could be used for cold emailing or promotional email marketing. |
https://en.wikipedia.org/wiki/Lactarius%20rubrilacteus | Lactarius rubrilacteus is a species of mushroom of the genus Lactarius. It is also known as the bleeding milkcap, as is at least one other member of the genus, Lactarius sanguifluus.
Description
The mushroom can have either a bluish green or an orangy brown hue, with creamy white or yellow spores that are ellipsoid in shape. Greenish colors are more common to old, damaged or unexpanded specimens. The cap of the mushroom is convex and sometimes shield-shaped and across, reaching a height of tall. The cap also has quite an underfolded margin and a depressive disk.
Lactarius rubrilacteus has many laticifers which appear as a white network across the surface of the mushroom. When sliced or cut, the mushroom flesh will typically release a dark red to purple latex or milky substance. The flesh itself will lose colour when damaged, and is usually granular or brittle to the touch. The stem is quite thin, being only several centimetres in any dimension, and is of an average size and shape for a mushroom. The fungus itself exudes a slight odour that is faintly aromatic. This mushroom is edible. Commonly found with a small blue or green mushroom attached at the base. Bruises green.
Similar species
Lactarius deliciosus is a related species, but its cap differs in appearance. L. sanguifluus is also similar.
Distribution and habitat
The mushroom is primarily found in parts of western North America, growing in forests and on the ground. The mushroom usually finds cover under conifer trees, mainly Douglas fir. It is widely distributed in these areas between the months of June and October.
Chemical reactivity
Potassium hydroxide: When the mushroom comes in contact with potassium hydroxide, most of the mushroom, including the mantle and ectomycorrhizae, loses its bluish hue and becomes a dull brown.
Melzer's reagent: Hardly any visible reaction on any part of the mushroom occurs. This particular mushroom appears to have little reactivity to Melzer's Reagent.
Sulfovanillin: Mo |
https://en.wikipedia.org/wiki/Bleeding%20milkcap | The term bleeding milkcap is used to describe at least two mushrooms of the genus Lactarius:
Lactarius rubrilacteus
Lactarius sanguifluus |
https://en.wikipedia.org/wiki/Eagle%20of%20Zeus | The Eagle of Zeus () was one of the chief attributes and personifications of Zeus, the head of the Olympian pantheon.
Eagles in antiquity
Eagles were considered the most prominent of birds in classical antiquity. Several legends attested to their unique qualities, such as Aristotle's claim that the sea eagle only raised the young who could look at the sun directly without their eyes watering, or Pliny the Elder's claim that they were immune to being struck by lightning, while the Geoponica claimed that they protected from hail. They were considered endowed with oracular properties, and a divine bird, as messenger of Zeus and herald of victory. In fact, Zeus himself is said to have transformed himself into an eagle on occasion.
From these divine associations, the eagle came to be used as an emblem of several rulers, from the Achaemenids to Alexander the Great and the Diadochi, and finally of the Roman emperors. Zeus being equated with Jupiter, the eagle holding Jupiter's lightning became the chief symbol (aquila) of the Roman legions. The eagle was placed amongst the stars as the constellation Aquila alongside Lyra.
Legends
There are several schools of thought regarding the origin of this eagle, coming from different Greek legends.
Aëtos
In one version, Aëtos was a childhood friend of Zeus who kept him company while the god was hiding in Crete from his father. After Zeus became king, Hera turned Aëtos into an eagle out of fear that Zeus was in love with him. Zeus made the eagle his most prominent and sacred symbol. In some versions, Aëtos is supplanted with Ganymede, the Trojan whom Zeus abducted in the form of an eagle.
Periphas
According to Antoninus Liberalis, Periphas was a legendary king of Attica who was a just king, and a dutiful priest of Apollo. Zeus, however, became indignant because Periphas was revered and honoured as if he were Zeus himself, so Zeus wanted to destroy Periphas and his entire household. But Apollo interceded, and instead Zeus trans |
https://en.wikipedia.org/wiki/Abel%E2%80%93Jacobi%20map | In mathematics, the Abel–Jacobi map is a construction of algebraic geometry which relates an algebraic curve to its Jacobian variety. In Riemannian geometry, it is a more general construction mapping a manifold to its Jacobi torus.
The name derives from the theorem of Abel and Jacobi that two effective divisors are linearly equivalent if and only if they are indistinguishable under the Abel–Jacobi map.
Construction of the map
In complex algebraic geometry, the Jacobian of a curve C is constructed using path integration. Namely, suppose C has genus g, which means topologically that
Geometrically, this homology group consists of (homology classes of) cycles in C, or in other words, closed loops. Therefore, we can choose 2g loops generating it. On the other hand, another more algebro-geometric way of saying that the genus of C is g is that
where K is the canonical bundle on C.
By definition, this is the space of globally defined holomorphic differential forms on C, so we can choose g linearly independent forms . Given forms and closed loops we can integrate, and we define 2g vectors
It follows from the Riemann bilinear relations that the generate a nondegenerate lattice (that is, they are a real basis for ), and the Jacobian is defined by
The Abel–Jacobi map is then defined as follows. We pick some base point and, nearly mimicking the definition of define the map
Although this is seemingly dependent on a path from to any two such paths define a closed loop in and, therefore, an element of so integration over it gives an element of Thus the difference is erased in the passage to the quotient by . Changing base-point does change the map, but only by a translation of the torus.
The Abel–Jacobi map of a Riemannian manifold
Let be a smooth compact manifold. Let be its fundamental group. Let be its abelianisation map. Let be the torsion subgroup of . Let be the quotient by torsion. If is a surface, is non-canonically isomorphic to , wher |
https://en.wikipedia.org/wiki/Metabolic%20flux%20analysis | Metabolic flux analysis (MFA) is an experimental fluxomics technique used to examine production and consumption rates of metabolites in a biological system. At an intracellular level, it allows for the quantification of metabolic fluxes, thereby elucidating the central metabolism of the cell. Various methods of MFA, including isotopically stationary metabolic flux analysis, isotopically non-stationary metabolic flux analysis, and thermodynamics-based metabolic flux analysis, can be coupled with stoichiometric models of metabolism and mass spectrometry methods with isotopic mass resolution to elucidate the transfer of moieties containing isotopic tracers from one metabolite into another and derive information about the metabolic network. Metabolic flux analysis (MFA) has many applications such as determining the limits on the ability of a biological system to produce a biochemical such as ethanol, predicting the response to gene knockout, and guiding the identification of bottleneck enzymes in metabolic networks for metabolic engineering efforts.
Metabolic flux analysis may use 13C-labeled isotope tracers for isotopic labeling experiments. Nuclear magnetic resonance (NMR) techniques and mass spectrometry may then be used to measure metabolite labeling patterns to provide information for determination of pathway fluxes. Because MFA typically requires rigorous flux calculation of complex metabolic networks, publicly available software tools have been developed to automate MFA and reduce its computational burden.
Experimental method
Although using a stoichiometric balance and constraints of the metabolites comprising the metabolic network can elucidate fluxes, this approach has limitations including difficulty in stimulating fluxes through parallel, cyclic, and reversible pathways. Moreover, there is limited insight on how metabolites interconvert in a metabolic network without the use of isotope tracers. Thus, the use of isotopes has become the dominant technique fo |
https://en.wikipedia.org/wiki/American%20Rocketry%20Challenge | The American Rocketry Challenge is an annual American model rocketry competition for students in grades six to 12 sponsored by the Aerospace Industries Association and the National Association of Rocketry. Co-sponsors include NASA, United States Department of Defense, the American Association of Physics Teachers and the Civil Air Patrol. Previously known as the "Team America Rocketry Challenge," the name was changed following the 2019 event.
The event receives local and national media coverage and usually draws well-known representatives of the Defense Department, NASA, the FAA, and other government agencies. Past National Fly-Offs have been attended by United States Secretary of Defense Robert Gates, Apollo 11 astronaut Buzz Aldrin, Rocket Boys author Homer Hickam, former NASA Administrator Sean O'Keefe, U.S. Senator Mike Enzi, and former NASA Administrator, Charles Bolden.
The 2010, 2011, 2013, 2015, and 2016 International Fly-Offs were won by the American winners of TARC.
History
The competition began in 2002 celebration of 100th anniversary of the flight, but due to a high level of interest became an annual occurrence. ARC fosters interest in aerospace engineering careers among its participants, and the National Fly-Off in May is an opportunity for corporations, universities, and the armed services to attract students. The program rebranded in 2019 to the American Rocketry Challenge.
Requirements
The requirements for each year's challenge are announced during the summer. Teams generally meet early in the school year, and must make official qualifying flights by early April. A team only has three chances to fly an official qualification attempt; only scores from flights that meet the contest requirements, are safe, and don't break the egg can be submitted. Typically, about 60 percent of participating teams submit at least one qualification score. The teams with the top 100 qualifying scores submitted in April compete in the National Fly-off that is held du |
https://en.wikipedia.org/wiki/Mobile%20Internet%20device | A mobile Internet device (MID) is a multimedia capable mobile device providing wireless Internet access. They are designed to provide entertainment, information and location-based services for personal or business use. They allow 2-way communication and real-time sharing. They have been described as filling a niche between smartphones and tablet computers.
As all the features of MID started becoming available on smartphones and tablets, the term is now mostly used to refer to both low-end as well as high-end tablets.
Archos Internet tablets
The form factor of mobile Internet tablets from Archos is very similar to the Lenovo image on the right. The class has included multiple operating systems: Windows CE, Windows 7 and Android. The Android tablet uses an ARM Cortex CPU and a touchscreen.
Intel announced a prototype MID at the Intel Developer Forum in Spring 2007 in Beijing. A MID development kit by Sophia Systems using Intel Centrino Atom was announced in April 2008.
Intel MID platforms are based on an Intel processor and chipset which consume less power than most of the x86 derivatives. A few platforms have been announced as listed below:
McCaslin platform (2007)
Intel's first generation MID platform (codenamed McCaslin) contains a 90 nm Intel A100/A110 processor (codenamed Stealey) which runs at 600–800 MHz.
Menlow platform (2008)
On 2 March 2008, Intel introduced the Intel Atom processor brand for a new family of low-power processor platforms. The components have thin, small designs and work together to "enable the best mobile computing and Internet experience" on mobile and low-power devices.
Intel's second generation MID platform (codenamed Menlow) contains a 45 nm Intel Atom processor (codenamed Silverthorne) which can run up to 2.0 GHz and a System Controller Hub (codenamed Poulsbo) which includes Intel HD Audio (codenamed Azalia). This platform was initially branded as Centrino Atom but such practice was discontinued in Q3 2008.
Moorestown platform ( |
https://en.wikipedia.org/wiki/Comparison%20of%20Microsoft%20Windows%20versions | Microsoft Windows is the name of several families of computer software operating systems created by Microsoft. Microsoft first introduced an operating environment named Windows in November 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces (GUIs).
All versions of Microsoft Windows are commercial proprietary software.
General information
Basic general information about Windows.
DOS shells
Has partial 32-bit compatibility with Win32s
Windows 9x
Windows NT
has also an N-edition
has also an N-edition
has also an N-edition
has a separate x64-edition
has also a Core-edition
has also an edition without HyperV
has also a Core-edition without HyperV
Windows Embedded Compact
Windows Embedded Compact (Windows CE) is a discontinued variation of Microsoft's Windows operating system for minimalistic computers and embedded systems. Windows CE was a distinctly different kernel, rather than a trimmed-down version of desktop Windows. It is supported on Intel x86 and is compatible on MIPS, ARM, and Hitachi SuperH processors.
Windows IoT
The Windows IoT family is the successor to the now-discontinued Windows Embedded family.
Windows Mobile
Windows Mobile is Microsoft's discontinued line of operating systems for smartphones.
Windows Phone
Windows Phone is Microsoft's discontinued line of operating systems for smartphones.
Technical information
DOS shells
Windows 9x
It is possible to install the MS-DOS variants 7.0 and 7.1 without the graphics user interface of Windows. If an independent installation of both, DOS and Windows is desired, DOS ought to be installed prior to Windows, at the start of a small partition. The system must be transferred by the (dangerous) "SYSTEM" DOS-command, while the other files constituting DOS can simply be copied (the files located in the DOS-root and the entire COMMAND directory). Such a stand-alone installation of MS-DOS 8 is not possible, as it is designed to work as real mode for Windows M |
https://en.wikipedia.org/wiki/GADGET | GADGET is free software for cosmological N-body/SPH simulations written by Volker Springel at the Max Planck Institute for Astrophysics. The name is an acronym of "GAlaxies with Dark matter and Gas intEracT". It is released under the GNU GPL. It can be used to study for example galaxy formation and dark matter.
Description
GADGET computes gravitational forces with a hierarchical tree algorithm (optionally in combination with a particle-mesh scheme for long-range gravitational forces) and represents fluids by means of smoothed-particle hydrodynamics (SPH). The code can be used for studies of isolated systems, or for simulations that include the cosmological expansion of space, both with or without periodic boundary conditions. In all these types of simulations, GADGET follows the evolution of a self-gravitating collisionless N-body system, and allows gas dynamics to be optionally included. Both the force computation and the time stepping of GADGET are fully adaptive, with a dynamic range which is, in principle, unlimited.
GADGET can therefore be used to address a wide array of astrophysically interesting problems, ranging from colliding and merging galaxies, to the formation of large-scale structure in the universe. With the inclusion of additional physical processes such as radiative cooling and heating, GADGET can also be used to study the dynamics of the gaseous intergalactic medium, or to address star formation and its regulation by feedback processes.
History
The first public version (GADGET-1, released in March 2000 was created as part of Volker's PhD project under the supervision of Simon White. Later, the code was continuously improved during postdocs of Volker Springel at the Center for Astrophysics Harvard & Smithsonian and the Max Planck Institute, in collaboration with Simon White and Lars Hernquist.
The second public version (GADGET-2, released in May 2005 contains most of these improvements, except for the numerous physics modules developed for the |
https://en.wikipedia.org/wiki/Borassus%20madagascariensis | Borassus madagascariensis is a species in the palm family Arecales endemic to Madagascar.
The palm is native to western Madagascar, where it is found along lowland watercourses in the dry forests below 100 meters elevation. It has a fragmented distribution and is known from only five locations.
The palm heart and newly germinated seedlings are edible, and an alcoholic drink is produced from the fruit. |
https://en.wikipedia.org/wiki/Bush%20hid%20the%20facts | Bush hid the facts is a common name for a bug present in some versions of Microsoft Windows, which causes text encoded in ASCII to be interpreted as if it were UTF-16LE, resulting in garbled text. When the string "Bush hid the facts", without quotes, was put in a new Notepad document and saved, closed, and reopened, the nonsensical sequence of the Chinese characters "" would appear instead.
While "Bush hid the facts" is the sentence most commonly presented on the Internet to induce the error, the bug can be triggered by other strings with letters and spaces in the same positions, for example or . Other sequences trigger the bug as well, including simply the text or . (This most commonly used sentence is a reference to U.S. President George W. Bush's statements about weapons of mass destruction in Iraq.)
The bug occurs when the string is passed to the Win32 charset detection function IsTextUnicode. IsTextUnicode sees that the bytes match the UTF-16LE encoding of assigned Unicode code points, concludes that the text is valid UTF-16LE, and returns true, and the application then incorrectly interprets the text as UTF-16LE.
The bug had existed since IsTextUnicode was introduced with in 1994, but was not discovered until early 2004. Many text editors and tools exhibit this behavior on Windows because they use IsTextUnicode to determine the encoding of text files. As of Windows Vista, Notepad has been modified to use a different detection algorithm that does not exhibit the bug, but IsTextUnicode remains unchanged in the operating system, so any other tools that use the function are still affected.
Workarounds
Several workarounds exist for this bug:
Editing the text to not be a pattern that triggers this bug will avoid it. For instance, adding a new line in the first 20 characters will work.
If the file is saved as "UTF-8" (before 2018) or "UTF-8 with BOM" (after 2018) rather than "ANSI" the text loads correctly, because Notepad prepends a UTF-8 byte order mark, wh |
https://en.wikipedia.org/wiki/Zobel%20network | For the wave filter invented by Zobel and sometimes named after him see m-derived filters.
Zobel networks are a type of filter section based on the image-impedance design principle. They are named after Otto Zobel of Bell Labs, who published a much-referenced paper on image filters in 1923. The distinguishing feature of Zobel networks is that the input impedance is fixed in the design independently of the transfer function. This characteristic is achieved at the expense of a much higher component count compared to other types of filter sections. The impedance would normally be specified to be constant and purely resistive. For this reason, Zobel networks are also known as constant resistance networks. However, any impedance achievable with discrete components is possible.
Zobel networks were formerly widely used in telecommunications to flatten and widen the frequency response of copper land lines, producing a higher performance line from one originally intended for ordinary telephone use. Analogue technology has given way to digital technology and they are now little used.
When used to cancel out the reactive portion of loudspeaker impedance, the design is sometimes called a Boucherot cell. In this case, only half the network is implemented as fixed components, the other half being the real and imaginary components of the loudspeaker impedance. This network is more akin to the power factor correction circuits used in electrical power distribution, hence the association with Boucherot's name.
A common circuit form of Zobel networks is in the form of a bridged T network. This term is often used to mean a Zobel network, sometimes incorrectly when the circuit implementation is not a bridged T.
Derivation
The basis of a Zobel network is a balanced bridge circuit as shown in the circuit to the right. The condition for balance is that;
If this is expressed in terms of a normalised Z0 = 1 as is conventionally done in filter tables, then the balance con |
https://en.wikipedia.org/wiki/Form%20classification | Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of science is to move "form taxa" to biological taxa whose affinity is known.
Form taxonomy is restricted to fossils that preserve too few characters for a conclusive taxonomic definition or assessment of their biological affinity, but whose study is made easier if a binomial name is available by which to identify them. The term "form classification" is preferred to "form taxonomy"; taxonomy suggests that the classification implies a biological affinity, whereas form classification is about giving a name to a group of morphologically-similar organisms that may not be related.
A "parataxon" (not to be confused with parataxonomy), or "sciotaxon" (Gr. "shadow taxon"), is a classification based on incomplete data: for instance, the larval stage of an organism that cannot be matched up with an adult. It reflects a paucity of data that makes biological classification impossible. A sciotaxon is defined as a taxon thought to be equivalent to a true taxon (orthotaxon), but whose identity cannot be established because the two candidate taxa are preserved in different ways and thus cannot be compared directly.
Examples
In zoology
Form taxa are groupings that are based on common overall forms. Early attempts at classification of labyrinthodonts was based on skull shape (the heavily armoured skulls often being the only preserved part). The amount of convergent evolution in the many groups lead to a number of polyphyletic taxa. Such groups are united by a common mode of life, often one that is generalist, in consequence acquiring generally similar body shapes by convergent evolution. Ediacaran biota — whether they are the precursors of the Cambrian explosion of the fossil record, or are unrelated to any modern phylum — can currently on |
https://en.wikipedia.org/wiki/E%C3%B6tv%C3%B6s%20experiment | The Eötvös experiment was a famous physics experiment that measured the correlation between inertial mass and gravitational mass, demonstrating that the two were one and the same, something that had long been suspected but never demonstrated with the same accuracy. The earliest experiments were done by Isaac Newton (1642–1727) and improved upon by Friedrich Wilhelm Bessel (1784–1846). A much more accurate experiment using a torsion balance was carried out by Loránd Eötvös starting around 1885, with further improvements in a lengthy run between 1906 and 1909. Eötvös's team followed this with a series of similar but more accurate experiments, as well as experiments with different types of materials and in different locations around the Earth, all of which demonstrated the same equivalence in mass. In turn, these experiments led to the modern understanding of the equivalence principle encoded in general relativity, which states that the gravitational and inertial masses are the same.
It is sufficient for the inertial mass to be proportional to the gravitational mass. Any multiplicative constant will be absorbed in the definition of the unit of force.
Eötvös's original experiment
Eötvös's original experimental device consisted of two masses on opposite ends of a rod, hung from a thin fiber. A mirror attached to the rod, or fiber, reflected light into a small telescope. Even tiny changes in the rotation of the rod would cause the light beam to be deflected, which would in turn cause a noticeable change when magnified by the telescope.
As seen from the Earth's frame of reference (or "lab frame", which is not an inertial frame of reference), the primary forces acting on the balanced masses are the string tension, gravity, and the centrifugal force due to the rotation of the Earth. Gravity is calculated by Newton's law of universal gravitation, which depends on gravitational mass. The centrifugal force is calculated by Newton's laws of motion and depends on inertial mas |
https://en.wikipedia.org/wiki/Enneagram%20of%20Personality | The Enneagram of Personality, or simply the Enneagram (from the Greek words [, meaning "nine"] and [, meaning something "written" or "drawn"]), is a model of the human psyche which is principally understood and taught as a typology of nine interconnected personality types.
Although the origins and history of ideas associated with the Enneagram of Personality are disputed, contemporary approaches are principally derived from the teachings of the Bolivian psycho-spiritual teacher Oscar Ichazo from the 1950s and the Chilean psychiatrist Claudio Naranjo from the 1970s. Naranjo's theories were also influenced by earlier teachings about personality by George Gurdjieff and the Fourth Way tradition in the first half of the 20th century.
As a typology, the Enneagram defines nine personality types (sometimes called "enneatypes"), which are represented by the points of a geometric figure called an enneagram, which indicate some of the principal connections between the types. There have been different schools of thought among Enneagram teachers and their understandings are not always in agreement.
The Enneagram of Personality is promoted in both business management and spirituality contexts through seminars, conferences, books, magazines, and DVDs. In business contexts, it is often promoted as a means to gain insights into workplace interpersonal dynamics; in spirituality it is commonly presented as a path to states of enlightenment and essence. Proponents in both contexts say it has aided in self-awareness, self-understanding, and self-development.
There has been limited formal psychometric analysis of the Enneagram, and the peer-reviewed research that has been done is not accepted within the relevant academic communities. Though the Enneagram integrates some concepts that parallel other theories of personality, it has been dismissed by personality assessment experts as pseudoscience.
History
The origins and historical development of the Enneagram of Personality are |
https://en.wikipedia.org/wiki/Generalised%20circle | In geometry, a generalized circle, sometimes called a cline or circline, is a straight line or a circle.
The natural setting for generalized circles is the extended plane, a plane along with one point at infinity through which every straight line is considered to pass. Given any three distinct points in the extended plane, there exists precisely one generalized circle passing through all three.
Generalized circles sometimes appear in Euclidean geometry, which has a well-defined notion of distance between points, and where every circle has a center and radius: the point at infinity can be considered infinitely distant from any other point, and a line can be considered as a degenerate circle without a well-defined center and with infinite radius (zero curvature). A reflection across a line is a Euclidean isometry (distance-preserving transformation) which maps lines to lines and circles to circles; but an inversion in a circle is not, distorting distances and mapping any line to a circle passing through the reference circles's center, and vice-versa.
However, generalized circles are fundamental to inversive geometry, in which circles and lines are considered indistinguishable, the point at infinity is not distinguished from any other point, and the notions of curvature and distance between points are ignored. In inversive geometry, reflections, inversions, and more generally their compositions, called Möbius transformations, map generalized circles to generalized circles, and preserve the inversive relationships between objects.
The extended plane can be identified with the sphere using a stereographic projection. The point at infinity then becomes an ordinary point on the sphere, and all generalized circles become circles on the sphere.
Extended complex plane
The extended Euclidean plane can be identified with the extended complex plane, so that equations of complex numbers can be used to describe lines, circles and inversions.
Bivariate linear equation
A c |
https://en.wikipedia.org/wiki/Homometric%20structures | In chemistry and crystallography, crystal structures that have the same set of interatomic distances are called homometric structures. Homometric structures need not be congruent (that is, related by a rigid motion or reflection). Homometric crystal structures produce identical diffraction patterns; therefore, they cannot be distinguished by a diffraction experiment.
Recently, a Monte Carlo algorithm was proposed to calculate the number of homometric structures corresponding to any given set of interatomic distances.
See also
Patterson function
Arthur Lindo Patterson |
https://en.wikipedia.org/wiki/International%20Union%20of%20Crystallography | The International Union of Crystallography (IUCr) is an organisation devoted to the international promotion and coordination of the science of crystallography. The IUCr is a member of the International Council for Science (ICSU).
Objectives
The objectives of the IUCr are to promote international cooperation in crystallography and to contribute to all aspects of crystallography, to promote international publication of crystallographic research, to facilitate standardization of methods, units, nomenclatures and symbols, and to form a focus for the relations of crystallography to other sciences.
The IUCr fulfils these objectives by publishing in print and electronically primary scientific journals through the Acta Crystallographica journal series, as well as Journal of Applied Crystallography, Journal of Synchrotron Radiation, IUCrJ, the series of reference volumes International Tables for Crystallography, distributing the quarterly IUCr Newsletter, maintaining the online World Directory/Database of Crystallographers, awarding the Ewald Prize and organising the triennial Congress and General Assembly.
History
In 1944 the yearly meeting of the X-ray Analysis Group (XRAG) of the UK Institute of Physics was held in Oxford, and the distinguished German crystallographer Paul Peter Ewald, who then taught at Queen's University Belfast, was invited to give the evening lecture. In it he gave a historical survey of some of the stages in the evolution of X-ray crystallography and ended with a strong plea for the formation of an international society or union which would represent, and unify publication for, the new science. This idea was followed up by the British crystallographers, and particularly by Sir Lawrence Bragg, the Chairman of XRAG. In June 1946, within a year of the termination of fighting in WWII, he arranged for an international meeting of crystallographers in London which was attended by some 120 scientists from most of the allied countries. In that London me |
https://en.wikipedia.org/wiki/Semiautomaton | In mathematics and theoretical computer science, a semiautomaton is a deterministic finite automaton having inputs but no output. It consists of a set Q of states, a set Σ called the input alphabet, and a function T: Q × Σ → Q called the transition function.
Associated with any semiautomaton is a monoid called the characteristic monoid, input monoid, transition monoid or transition system of the semiautomaton, which acts on the set of states Q. This may be viewed either as an action of the free monoid of strings in the input alphabet Σ, or as the induced transformation semigroup of Q.
In older books like Clifford and Preston (1967) semigroup actions are called "operands".
In category theory, semiautomata essentially are functors.
Transformation semigroups and monoid acts
A transformation semigroup or transformation monoid is a pair consisting of a set Q (often called the "set of states") and a semigroup or monoid M of functions, or "transformations", mapping Q to itself. They are functions in the sense that every element m of M is a map . If s and t are two functions of the transformation semigroup, their semigroup product is defined as their function composition .
Some authors regard "semigroup" and "monoid" as synonyms. Here a semigroup need not have an identity element; a monoid is a semigroup with an identity element (also called "unit"). Since the notion of functions acting on a set always includes the notion of an identity function, which when applied to the set does nothing, a transformation semigroup can be made into a monoid by adding the identity function.
M-acts
Let M be a monoid and Q be a non-empty set. If there exists a multiplicative operation
which satisfies the properties
for 1 the unit of the monoid, and
for all and , then the triple is called a right M-act or simply a right act. In long-hand, is the right multiplication of elements of Q by elements of M. The right act is often written as .
A left act is defined similarly, with
|
https://en.wikipedia.org/wiki/Transition%20system | In theoretical computer science, a transition system is a concept used in the study of computation. It is used to describe the potential behavior of discrete systems. It consists of states and transitions between states, which may be labeled with labels chosen from a set; the same label may appear on more than one transition. If the label set is a singleton, the system is essentially unlabeled, and a simpler definition that omits the labels is possible.
Transition systems coincide mathematically with abstract rewriting systems (as explained further in this article) and directed graphs. They differ from finite-state automata in several ways:
The set of states is not necessarily finite, or even countable.
The set of transitions is not necessarily finite, or even countable.
No "start" state or "final" states are given.
Transition systems can be represented as directed graphs.
Formal definition
Formally, a transition system is a pair where is a set of states and , the transition relation, is a subset of . We say that there is a transition from state to state iff , and denote it .
A labelled transition system is a tuple where is a set of states, is a set of labels, and , the labelled transition relation, is a subset of . We say that there is a transition from state to state with label iff and denote it
Labels can represent different things depending on the language of interest. Typical uses of labels include representing input expected, conditions that must be true to trigger the transition, or actions performed during the transition. Labelled transitions systems were originally introduced as named transition systems.
Special cases
If, for any given and , there exists only a single tuple in , then one says that is deterministic (for ).
If, for any given and , there exists at least one tuple in , then one says that is executable (for ).
Coalgebra formulation
The formal definition can be rephrased as follows. Labelled state transit |
https://en.wikipedia.org/wiki/Software%20system | A software system is a system of intercommunicating components based on software forming part of a computer system (a combination of hardware and software). It "consists of a number of separate programs, configuration files, which are used to set up these programs, system documentation, which describes the structure of the system, and user documentation, which explains how to use the system".
The term "software system" should be distinguished from the terms "computer program" and "software". The term computer program generally refers to a set of instructions (source, or object code) that perform a specific task. However, a software system generally refers to a more encompassing concept with many more components such as specification, test results, end-user documentation, maintenance records, etc.
The use of the term software system is at times related to the application of systems theory approaches in the context of software engineering. A software system consists of several separate computer programs and associated configuration files, documentation, etc., that operate together. The concept is used in the study of large and complex software, because it focuses on the major components of software and their interactions. It is also related to the field of software architecture.
Software systems are an active area of research for groups interested in software engineering in particular and systems engineering in general. Academic journals like the Journal of Systems and Software (published by Elsevier) are dedicated to the subject.
The ACM Software System Award is an annual award that honors people or an organization "for developing a system that has had a lasting influence, reflected in contributions to concepts, in commercial acceptance, or both". It has been awarded by the Association for Computing Machinery (ACM) since 1983, with a cash prize sponsored by IBM.
The two types of are system software and application software
Categories
Major categories of software |
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