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https://en.wikipedia.org/wiki/Inferior%20thyroid%20veins
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The inferior thyroid veins appear two, frequently three or four, in number, and arise in the venous plexus on the thyroid gland, communicating with the middle and superior thyroid veins. While the superior and middle thyroid veins serve as direct tributaries to the internal jugular vein, the inferior thyroid veins drain directly to the brachiocephalic veins.
The inferior thyroid veins form a plexus in front of the trachea, behind the sternothyroid muscle. From this plexus, the left vein descends and joins the left brachiocephalic vein, and the right vein passes obliquely downward and to the right across the brachiocephalic artery to open into the right brachiocephalic vein, just at its junction with the superior vena cava; sometimes the right and left veins open by a common trunk in the latter situation.
The inferior thyroid veins receive esophageal, tracheal, and inferior laryngeal veins, and are provided with valves at their terminations in the brachiocephalic veins.
Additional images
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https://en.wikipedia.org/wiki/Left%20gastroepiploic%20vein
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The left gastroepiploic vein (left gastro-omental vein) receives branches from the antero-superior and postero-inferior surfaces of the stomach and from the greater omentum; it runs from right to left along the greater curvature of the stomach and ends in the commencement of the splenic vein.
The splenic vein and superior mesenteric vein join to form the hepatic portal vein.
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https://en.wikipedia.org/wiki/Route%20Views
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RouteViews is a project founded by the Advanced Network Technology Center at the University of Oregon to allow Internet users to view global Border Gateway Protocol routing information from the perspective of other locations around the internet. Originally created to help Internet Service Providers determine how their network prefixes were viewed by others in order to debug and optimize access to their network, RouteViews is now used for a range of other purposes including academic research.
RouteViews collectors obtain BGP data by directly peering with network operators at Internet exchange points or by multi-hop peering with network operators that aren't colocated at an exchange where RouteViews has a collector. The collectors can be queried using telnet. Historical data is stored in MRT format and can be downloaded using HTTP or FTP from archive.routeviews.org.
As of 2023, the RouteViews project has collectors at 39 exchange points and more than 1,000 peers.
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https://en.wikipedia.org/wiki/Middle%20thyroid%20vein
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The middle thyroid vein () collects the blood from the lower portion of the thyroid gland. It receives tributaries that drain the larynx, and trachea. It passes anterior to the common carotid artery to reach and drain into the internal jugular vein.
Anatomy
Fate
It empties into the internal jugular vein posterior to the superior belly of the omohyoid muscle.
Clinical significance
This vein is subjected for dissection as a part of surgical procedures on the thyroid.
Additional images
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https://en.wikipedia.org/wiki/Al-Khansaa%20%28magazine%29
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Al-Khansaa was an online women's magazine launched in 2004 by a Saudi branch of al-Qaeda.
The magazine claimed to have been founded by Saudi leader Abd-al-Aziz al-Muqrin shortly before his death. It offered advice on first aid for wounded family members, how to raise children to believe in Jihad and physical training for women to prepare for combat.
The magazine was named after Al-Khansaa, an Arab poet and a contemporary of Muhammad.
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https://en.wikipedia.org/wiki/Maxillary%20vein
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The maxillary vein or internal maxillary vein is a vein of the head. It is a short trunk which accompanies (the first part of) the maxillary artery. It is formed by a confluence of the veins of the pterygoid plexus. It and passes posterior-ward between the sphenomandibular ligament and the neck of the mandible to enter the parotid gland where unites with the superficial temporal vein to form the retromandibular vein (posterior facial vein).
Structure
Development
The maxillary vein may be the embryological origin of the central retinal vein.
Additional images
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https://en.wikipedia.org/wiki/Primordial%20Soup%20%28board%20game%29
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Primordial Soup is a board game designed by Doris Matthäus & Frank Nestel and published by Z-Man Games. It was first published in 1997 in Germany by Doris & Frank under the name Ursuppe and this original version won 2nd prize in the 1998 Deutscher Spiele Preis.
Theme
Each player guides a species of primitive amoeba drifting through the primordial soup. The player controls whether and how their amoebas move, eat and procreate using the 10 biological points which s/he receives each turn. A player may evolve their species by buying gene cards, which give the amoebas abilities such as faster movement. The abilities are pictured on the gene cards, showing amoebas growing fins, tentacles, spines, etc.
A key feature of the game is its self-balancing ecosystem. The food required by each amoeba is a mixture of the excrement of the other players' species. Food may become scarce and cause amoebas to starve, die and decompose into food. If one species becomes scarce, this will then cause problems for the other players, since their amoebas depend on all the other species to supply their food. Genes may mitigate this, for example by turning a species into a predator. However, this still requires some healthy prey to be available. Furthermore, the other players may react by turning their amoebas into predators themselves, growing spines for defense, or simply increase their procreation rate to offset the losses. The success of each strategy highly depends on the other players' actions as each species evolves to fill ecological niches.
Objective
Each turn each species scores points based upon its population and genes. The game ends when a player reaches 42 points or when the last environment card is drawn. This usually happens after 5-10 rounds so the game lasts 1–2 hours.
Equipment
A game board with spaces representing the primordial soup, a scoring track, and a compass diagram.
Two dice.
28 pegged discs representing amoebas, in four sets of different colors and shapes.
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https://en.wikipedia.org/wiki/Veratridine
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Veratridine is a steroidal alkaloid found in plants of the lily family, specifically the genera Veratrum and Schoenocaulon. Upon absorption through the skin or mucous membranes, it acts as a neurotoxin by binding to and preventing the inactivation of voltage-gated sodium ion channels in heart, nerve, and skeletal muscle cell membranes. Veratridine increases nerve excitability and intracellular Ca2+ concentrations.
Isolation
Veratridine has been isolated from the seeds of Schoenocaulon officinale and from the rhizomes of Veratrum album. Like the other steroidal alkaloids found in these plants and similar ones in the Melanthiaceae family, it is present as part of a glycosidal combination, bonded to carbohydrate moieties.
Early isolation methods relied on formation of the nitrate salt and then precipitation of the insoluble sulfate form. Accounts of these efforts date back to 1878, but the first true purification of veratridine is the one carried out in 1953 by Kupchan et al. This, and later purification procedures, begin with veratrine, a mixture of the alkaloids present in the Veratrum plants, primarily containing cevadine and veratridine. The nitrate salt is formed by dissolving the veratrine in 1% sulfuric acid over ice and precipitating with sodium nitrate. After resuspending in water over ice, the solution is brought to pH 8.5 with aqueous NaOH and then pH 10 with aqueous ammonia, forming another precipitate which is extracted with ether and then with chloroform. The ether and chloroform fractions are combined and dried. The dried residue is dissolved in sulfuric acid and the sulfate salt of veratridine is precipitated by dropwise addition of a solution of ammonium sulfate. Finally, the free base form is generated with ammonium hydroxide.
An even better isolation of veratridine from veratrine is achieved using high-performance liquid chromatography (HPLC); as commercially available veratridine may vary in purity, HPLC purification of veratrine is a preferred m
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https://en.wikipedia.org/wiki/Pterygoid%20plexus
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The pterygoid plexus (; from Greek pteryx, "wing" and eidos, "shape") is a fine venous plexus upon and within the lateral pterygoid muscle. It drains by a short maxillary vein.
Anatomy
It is a venous plexus of considerable size, situated between the temporalis muscle and lateral pterygoid muscle, and partly between the two pterygoid muscles.
The plexus features venous valves. The contractions of the lateral pterygoid muscle promote venous drainage.
Tributaries
The plexus drains all veins that correspond to the branches of the maxillary artery (however, much of the blood delivered by the maxillary artery is returned by other routes), as well as two additional veins.
It receives the following veins:
sphenopalatine
middle meningeal
deep temporal (anterior & posterior)
pterygoid
masseteric
buccinator
alveolar
some palatine veins (palatine vein which divides into the greater and lesser palatine v.)
inferior ophthalmic vein
deep facial vein
infraorbital vein
Anastomoses
The plexus is connected with the intercranial cavernous sinus by emissary veins passing through the foramen ovale and foramen lacerum.
Relations
This plexus communicates freely with the anterior facial vein; it also communicates with the cavernous sinus, by branches through the foramen Vesalii, foramen ovale, and foramen lacerum. Due to its communication with the cavernous sinus, infection of the superficial face may spread to the cavernous sinus, causing cavernous sinus thrombosis. Complications may include edema of the eyelids, conjunctivae of the eyes, and subsequent paralysis of cranial nerves which course through the cavernous sinus.
The pterygoid plexus of veins becomes the maxillary vein. The maxillary vein and the superficial temporal vein later join to become the retromandibular vein. The posterior branch of the retromandibular vein and posterior auricular vein then form the external jugular vein, which empties into the subclavian vein.
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https://en.wikipedia.org/wiki/Ceramic%20engineering
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Ceramic engineering is the science and technology of creating objects from inorganic, non-metallic materials. This is done either by the action of heat, or at lower temperatures using precipitation reactions from high-purity chemical solutions. The term includes the purification of raw materials, the study and production of the chemical compounds concerned, their formation into components and the study of their structure, composition and properties.
Ceramic materials may have a crystalline or partly crystalline structure, with long-range order on atomic scale. Glass ceramics may have an amorphous or glassy structure, with limited or short-range atomic order. They are either formed from a molten mass that solidifies on cooling, formed and matured by the action of heat, or chemically synthesized at low temperatures using, for example, hydrothermal or sol-gel synthesis.
The special character of ceramic materials gives rise to many applications in materials engineering, electrical engineering, chemical engineering and mechanical engineering. As ceramics are heat resistant, they can be used for many tasks for which materials like metal and polymers are unsuitable. Ceramic materials are used in a wide range of industries, including mining, aerospace, medicine, refinery, food and chemical industries, packaging science, electronics, industrial and transmission electricity, and guided lightwave transmission.
History
The word "ceramic" is derived from the Greek word () meaning pottery. It is related to the older Indo-European language root "to burn". "Ceramic" may be used as a noun in the singular to refer to a ceramic material or the product of ceramic manufacture, or as an adjective. Ceramics is the making of things out of ceramic materials. Ceramic engineering, like many sciences, evolved from a different discipline by today's standards. Materials science engineering is grouped with ceramics engineering to this day.
Abraham Darby first used coke in 1709 in Shropshir
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https://en.wikipedia.org/wiki/Cole%E2%80%93Cole%20equation
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The Cole–Cole equation is a relaxation model that is often used to describe dielectric relaxation in polymers.
It is given by the equation
where is the complex dielectric constant, and are the "static" and "infinite frequency" dielectric constants, is the angular frequency and is a dielectric relaxation time constant.
The exponent parameter , which takes a value between 0 and 1, allows the description of different spectral shapes. When , the Cole-Cole model reduces to the Debye model. When , the relaxation is stretched. That is, it extends over a wider range on a logarithmic scale than Debye relaxation.
The separation of the complex dielectric constant was reported in the original paper by Kenneth Stewart Cole and Robert Hugh Cole as follows:
Upon introduction of hyperbolic functions, the above expressions reduce to:
Here .
These equations reduce to the Debye expression when .
The Cole-Cole equation's time domain current response corresponds to the Curie–von Schweidler law and the charge response corresponds to the stretched exponential function or the Kohlrausch–Williams–Watts (KWW) function, for small time arguments.
Cole–Cole relaxation constitutes a special case of Havriliak–Negami relaxation when the symmetry parameter , that is, when the relaxation peaks are symmetric. Another special case of Havriliak–Negami relaxation where and is known as Cole–Davidson relaxation. For an abridged and updated review of anomalous dielectric relaxation in disordered systems, see Kalmykov.
See also
Debye relaxation
Cole–Davidson relaxation
Havriliak–Negami relaxation
Curie–von Schweidler law
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https://en.wikipedia.org/wiki/AOSS
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AOSS (AirStation One-Touch Secure System) is a system by Buffalo Technology which allows a secure wireless connection to be set up with the push of a button. AirStation residential gateways incorporated a button on the unit to let the user initiate this procedure. AOSS was designed to use the maximum level of security available to both connecting devices, including both Wired Equivalent Privacy (WEP) and Wi-Fi Protected Access (WPA).
Connection Process
Association Phase: Once AOSS has been initiated on both devices via the AOSS button, the access point will change its SSID to "ESSID-AOSS" and the client will attempt to connect to it. Both devices will attempt connection for two minutes. Connection will be made using a secret 64-bit WEP key known to both devices.
Key Generation Phase: With both devices connected, the AP generates and transfers a unique key to the client, where an RC4 tunnel is created. The AP creates four SSIDs and encryption keys for AES, TKIP, WEP128, and WEP64 generated from a random key script. These keys are available in the user interface of the AOSS AP to be used with non-AOSS clients.
Information Exchange Phase: The client notifies the AP of its encryption support.
Key Transfer Phase: All four encryption keys are transmitted to the client regardless of encryption support, allowing the client to change the SSID if needed. The user does not have access to the keys through the client device.
Reboot Stack: The AP applies the SSID and key for the highest level of encryption supported by the client and reboots. The previously used WEP64 and RC4 tunnel are no longer used. The client adapter will automatically reboot or re-initialize and connect to the SSID using the proper encryption key.
If a subsequent AOSS process connects with a lesser wireless encryption standard, the AP will apply the lesser standard and the Reboot Stack phase will be repeated for all connected devices.
Compatible products
The Nintendo Wi-Fi Connection used b
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https://en.wikipedia.org/wiki/Response%20surface%20methodology
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In statistics, response surface methodology (RSM) explores the relationships between several explanatory variables and one or more response variables. The method was introduced by George E. P. Box and K. B. Wilson in 1951. The main idea of RSM is to use a sequence of designed experiments to obtain an optimal response. Box and Wilson suggest using a second-degree polynomial model to do this. They acknowledge that this model is only an approximation, but they use it because such a model is easy to estimate and apply, even when little is known about the process.
Statistical approaches such as RSM can be employed to maximize the production of a special substance by optimization of operational factors. Of late, for formulation optimization, the RSM, using proper design of experiments (DoE), has become extensively used. In contrast to conventional methods, the interaction among process variables can be determined by statistical techniques.
Basic approach of response surface methodology
An easy way to estimate a first-degree polynomial model is to use a factorial experiment or a fractional factorial design. This is sufficient to determine which explanatory variables affect the response variable(s) of interest. Once it is suspected that only significant explanatory variables are left, then a more complicated design, such as a central composite design can be implemented to estimate a second-degree polynomial model, which is still only an approximation at best. However, the second-degree model can be used to optimize (maximize, minimize, or attain a specific target for) the response variable(s) of interest.
Important RSM properties and features
OrthogonalityThe property that allows individual effects of the k-factors to be estimated independently without (or with minimal) confounding. Also orthogonality provides minimum variance estimates of the model coefficient so that they are uncorrelated.
RotatabilityThe property of rotating points of the design about th
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https://en.wikipedia.org/wiki/Sonobe
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The Sonobe module is one of the many units used to build modular origami. The popularity of Sonobe modular origami models derives from the simplicity of folding the modules, the sturdy and easy assembly, and the flexibility of the system.
History
The origin of the Sonobe module is unknown. Two possible creators are Toshie Takahama and Mitsunobu Sonobe, who published several books together and both members of Sosaku Origami Group 67. The earliest appearance of a Sonobe module was in a cube attributed to Mitsunobu Sonobe in a Sosaku Origami Group book published in 1968, however it does not reveal whether he invented the module or used an earlier design: the phrase "finished model by Mitsunobu Sonobe" is ambiguous. Its next appearance was "Toshie's Jewel", which appeared in 1974. However neither folder took advantage of the full potential of the module. This potential was discovered in the 1970s by other folders – particularly Steve Krimball, who created the 30-unit ball – as part of a sudden period of development in modular origami. Despite the module's importance and continued popularity, its designer remains uncertain.
Description
Each individual unit is folded from a square sheet of paper, of which only one face is visible in the finished module; many ornamented variants of the plain Sonobe unit that expose both sides of the paper have been designed.
The Sonobe unit has the shape of a parallelogram with 45 and 135 degrees angles, divided by creases into two diagonal tabs at the ends and two corresponding pockets within the inscribed center square. The system can build a wide range of three-dimensional geometric forms by docking these tabs into the pockets of adjacent units. Three interconnected Sonobe units will form an open-bottomed triangular pyramid with an equilateral triangle for the open bottom, and isosceles right triangles as the other three faces. It will have a right-angle apex (equivalent to the corner of a cube) and three tab/pocket flaps protrudin
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https://en.wikipedia.org/wiki/Ultimate%20Guitar
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Ultimate Guitar (Ultimate Guitar USA LLC), also known as Ultimate-Guitar.com or simply UG, is an online platform for guitarists and musicians. Its website and mobile application provides guitar tablature catalogues and chord sheets. UG's platform also includes video courses, reviews of music and equipment, interviews with notable musicians and forums. It was started on October 9, 1998, by Eugeny Naidenov. Since 2008, Ultimate Guitar operates from San Francisco, US, with its platform available in most countries. As of December 2021, the site and mobile app contain 1,600,000 tabs and chords for over 900,000 songs from over 115,000 artists. The UG app (also known as 'Tabs') has been downloaded more than 53,000,000 times.
Community
UG has over 43 million registered users. The website is regulated by an administrator and moderators. Moderators are users who are rewarded for being particularly helpful and knowledgeable in a specific subject and are responsible for moderating forums that focus on the subject they specialize in. Inappropriate words were formerly censored by a computer that searched for and replaced undesired words posted within the community, until September 1, 2015, when censorship of curse and swear words was discontinued. Community members may also create guitar lessons, and have their approved works published on the website and accessed by its users. Reviews of albums, multimedia, gear, and news articles can also be submitted by members.
Like the tabs, the lessons and columns are also rated by users, which contribute to the creator's "UG Points". A user's UG score increases or decreases as other members rate their contributions.
Although UG encourages participation, they also have a strict guideline and set of rules that all UG users must follow. Members must be over the age of 13 to use the services offered by the site and only one account is allowed to be made per person. Strong media is also prohibited from use on the site.
Some members of the
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https://en.wikipedia.org/wiki/Van%20%27t%20Hoff%20equation
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The Van 't Hoff equation relates the change in the equilibrium constant, , of a chemical reaction to the change in temperature, T, given the standard enthalpy change, , for the process. The subscript means "reaction" and the superscript means "standard". It was proposed by Dutch chemist Jacobus Henricus van 't Hoff in 1884 in his book Études de Dynamique chimique (Studies in Dynamic Chemistry).
The Van 't Hoff equation has been widely utilized to explore the changes in state functions in a thermodynamic system. The Van 't Hoff plot, which is derived from this equation, is especially effective in estimating the change in enthalpy and entropy of a chemical reaction.
Equation
Summary and uses
The standard pressure, , is used to define the reference state for the Van 't Hoff equation, which is
where denotes the natural logarithm, is the thermodynamic equilibrium constant, and is the ideal gas constant. This equation is exact at any one temperature and all pressures, derived from the requirement that the Gibbs free energy of reaction be stationary in a state of chemical equilibrium.
In practice, the equation is often integrated between two temperatures under the assumption that the standard reaction enthalpy is constant (and furthermore, this is also often assumed to be equal to its value at standard temperature). Since in reality and the standard reaction entropy do vary with temperature for most processes, the integrated equation is only approximate. Approximations are also made in practice to the activity coefficients within the equilibrium constant.
A major use of the integrated equation is to estimate a new equilibrium constant at a new absolute temperature assuming a constant standard enthalpy change over the temperature range. To obtain the integrated equation, it is convenient to first rewrite the Van 't Hoff equation as
The definite integral between temperatures and is then
In this equation is the equilibrium constant at absolute temperatu
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https://en.wikipedia.org/wiki/Lusitanosaurus
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Lusitanosaurus (meaning "Portuguese lizard") is a genus of large basal thyreophoran dinosaur from the Sinemurian stage of Early Jurassic of Portugal. It is the second example of the group from the Lower Jurassic of Europe and it is the oldest known dinosaur from the Iberian Peninsula. It is based on a large left maxilla with teeth that was lost in the fire at Museu Nacional de História Natural e da Ciência, Lisbon, in 1978.
Description
The fossil consists of a single partial left maxilla, an upper jaw bone, with seven teeth. The jaw measured 10.5 cm, with an estimated skull of 38.7 cm for the living animal. The teeth possess similarities with that of Scelidosaurus, which approaches it narrowly by the presence of important anterior and posterior basilar points on each tooth. The maxilla was clearly bigger, being the double of the size than the maxilla of Scelidosaurus. Lapparent & Zbyszewski vinculated it originally with Scelidosaurus and assigned the two to Stegosauria, he described that the teeth present were different to Scelidosaurus. Ginsburg cited the specimen and note a bigger size than the holotype of Scelidosaurus. Lusitanosaurus was probably a semibipedal to quadrupedal herbivore, with a dense armour on most parts of the body.
History of discovery
The genus was first described by Albert-Félix de Lapparent and Georges Zbyszewski in 1957. The type species is Lusitanosaurus liasicus. The generic name is derived from Lusitania, the ancient Latin name for the region. The specific name refers to the Lias. The holotype was part of the collection of the Museu de História Natural da Universidade de Lisboa. The exact location of the find and the date of collection are unknown, which makes a correct geological dating difficult, but it can be inferred from the matrix rock that it has been discovered near São Pedro de Moel, in strata from the Late Sinemurian (Early Jurassic). This would make it the oldest known dinosaur from Portugal.
Classification
It was originally
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https://en.wikipedia.org/wiki/Coverity
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Coverity is a proprietary static code analysis tool from Synopsys. This product enables engineers and security teams to find and fix software defects.
Coverity started as an independent software company in 2002 at the Computer Systems Laboratory at Stanford University in Palo Alto, California. It was founded by Benjamin Chelf, Andy Chou, and Seth Hallem with Stanford professor Dawson Engler as a technical adviser. The headquarters was moved to San Francisco. In June 2008, Coverity acquired Solidware Technologies. In February 2014, Coverity announced an agreement to be acquired by Synopsys, an electronic design automation company, for $350 million net of cash on hand.
Products
Coverity is a static code analysis tool for C, C++, C#, Java, JavaScript, PHP, Python, .NET, ASP.NET, Objective-C, Go, JSP, Ruby, Swift, Fortran, Scala, VB.NET, and TypeScript. It also supports more than 70 different frameworks for Java, JavaScript, C# and other languages.
Coverity Scan is a free static-analysis cloud-based service for the open source community.
Applications
Under a United States Department of Homeland Security contract in 2006, the tool was used to examine over 150 open source applications for bugs; 6000 bugs found by the scan were fixed across 53 projects.
National Highway Traffic Safety Administration used the tool in its 2010-2011 investigation into reports of sudden unintended acceleration in Toyota vehicles. The tool was used by CERN on the software employed in the Large Hadron Collider and in the NASA Jet Propulsion Laboratory during the flight software development of the Mars rover Curiosity.
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https://en.wikipedia.org/wiki/Frascati%20Tokamak%20Upgrade
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The Frascati Tokamak Upgrade (FTU) is a tokamak operating at Frascati, Italy. Building on the Frascati Tokamak experiment, FTU is a compact, high-magnetic-field tokamak (Btor = 8 Tesla ). It began operation in 1990 and has since achieved operating goals of 1.6 MA at 8 T and average electron density greater than 4 per cubic meter.
The poloidal section of FTU is circular, with a limiter.
External links
Official website
Tokamaks
Science and technology in Italy
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https://en.wikipedia.org/wiki/Metabolic%20waste
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Metabolic wastes or excrements are substances left over from metabolic processes (such as cellular respiration) which cannot be used by the organism (they are surplus or toxic), and must therefore be excreted. This includes nitrogen compounds, water, CO2, phosphates, sulphates, etc. Animals treat these compounds as excretes. Plants have metabolic pathways which transforms some of them (primarily the oxygen compounds) into useful substances..
All the metabolic wastes are excreted in a form of water solutes through the excretory organs (nephridia, Malpighian tubules, kidneys), with the exception of CO2, which is excreted together with the water vapor throughout the lungs. The elimination of these compounds enables the chemical homeostasis of the organism.
Nitrogen wastes
The nitrogen compounds through which excess nitrogen is eliminated from organisms are called nitrogenous wastes () or nitrogen wastes. They are ammonia, urea, uric acid, and creatinine. All of these substances are produced from protein metabolism. In many animals, the urine is the main route of excretion for such wastes; in some, it is the feces.
Ammonotelism
Ammonotelism is the excretion of ammonia and ammonium ions. Ammonia (NH3) forms with the oxidation of amino groups.(-NH2), which are removed from the proteins when they convert into carbohydrates. It is a very toxic substance to tissues and extremely soluble in water. Only one nitrogen atom is removed with it. A lot of water is needed for the excretion of ammonia, about 0.5 L of water is needed per 1 g of nitrogen to maintain ammonia levels in the excretory fluid below the level in body fluids to prevent toxicity. Thus, the marine organisms excrete ammonia directly into the water and are called ammonotelic. Ammonotelic animals include crustaceans, platyhelminths, cnidarians, poriferans, echinoderms, and other aquatic invertebrates.
Ureotelism
The excretion of urea is called ureotelism. Land animals, mainly amphibians and mammals, convert
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https://en.wikipedia.org/wiki/Hilbert%20spectrum
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The Hilbert spectrum (sometimes referred to as the Hilbert amplitude spectrum), named after David Hilbert, is a statistical tool that can help in distinguishing among a mixture of moving signals. The spectrum itself is decomposed into its component sources using independent component analysis. The separation of the combined effects of unidentified sources (blind signal separation) has applications in climatology, seismology, and biomedical imaging.
Conceptual summary
The Hilbert spectrum is computed by way of a 2-step process consisting of:
Preprocessing a signal separate it into intrinsic mode functions using a mathematical decomposition such as singular value decomposition (SVD) or empirical mode decomposition (EMD);
Applying the Hilbert transform to the results of the above step to obtain the instantaneous frequency spectrum of each of the components.
The Hilbert transform defines the imaginary part of the function to make it an analytic function (sometimes referred to as a progressive function), i.e. a function whose signal strength is zero for all frequency components less than zero.
With the Hilbert transform, the singular vectors give instantaneous frequencies that are functions of time, so that the result is an energy distribution over time and frequency.
The result is an ability to capture time-frequency localization to make the concept of instantaneous frequency and time relevant (the concept of instantaneous frequency is otherwise abstract or difficult to define for all but monocomponent signals).
Definition
For a given signal decomposed (with for example Empirical Mode Decomposition) to
where is the number of intrinsic mode functions that consists of and
The instantaneous angle frequency is then defined as
From this, we can define the Hilbert Spectrum for as
The Hilbert Spectrum of is then given by
Marginal Hilbert Spectrum
A two dimensional representation of a Hilbert Spectrum, called Marginal Hilbert Spectrum, is defined as
where
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https://en.wikipedia.org/wiki/Right%20gastroepiploic%20artery
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The right gastroepiploic artery (or right gastro-omental artery) is one of the two terminal branches of the gastroduodenal artery. It runs from right to left along the greater curvature of the stomach, between the layers of the greater omentum, anastomosing with the left gastroepiploic artery, a branch of the splenic artery.
Except at the pylorus where it is in contact with the stomach, it lies about a finger's breadth from the greater curvature.
Branches
This vessel gives off numerous branches:
"gastric branches": ascend to supply both surfaces of the stomach.
"omental branches": descend to supply the greater omentum and anastomose with branches of the middle colic.
Use in coronary artery surgery
The right gastroepiploic artery was first used as a coronary artery bypass graft (CABG) in 1984 by John Pym and colleagues at Queen's University. It has become an accepted alternative conduit, and is particularly useful in patients who do not have suitable saphenous veins to harvest for grafts. The right gastroepiploic artery is typically used as a graft to coronary arteries on the posterior wall of the heart such as the right coronary artery and the posterior descending branch.
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https://en.wikipedia.org/wiki/Left%20gastroepiploic%20artery
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The left gastroepiploic artery (or left gastro-omental artery), the largest branch of the splenic artery, runs from left to right about a finger's breadth or more from the greater curvature of the stomach, between the layers of the greater omentum, and anastomoses with the right gastroepiploic (a branch of the right gastro-duodenal artery originating from the hepatic branch of the coeliac trunk).
In its course it distributes:
"Gastric branches": several ascending branches to both surfaces of the stomach;
"Omental branches": descend to supply the greater omentum and anastomose with branches of the middle colic.
Additional images
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https://en.wikipedia.org/wiki/Median%20sacral%20artery
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The median sacral artery (or middle sacral artery) is a small artery that arises posterior to the abdominal aorta and superior to its bifurcation.
Structure
The median sacral artery arises from the abdominal aorta at the level of the bottom quarter of the third lumbar vertebra. It descends in the middle line in front of the fourth and fifth lumbar vertebrae, the sacrum and coccyx, ending in the glomus coccygeum (coccygeal gland).
Minute branches pass from it, to the posterior surface of the rectum.
On the last lumbar vertebra it anastomoses with the lumbar branch of the iliolumbar artery; in front of the sacrum it anastomoses with the lateral sacral arteries, sending offshoots into the anterior sacral foramina.
It is crossed by the left common iliac vein and accompanied by a pair of venae comitantes; these unite to form a single vessel that opens into the left common iliac vein.
Development
The median sacral artery is morphologically the direct continuation of the abdominal aorta. It is vestigial in humans, but large in animals with tails, such as the crocodile.
See also
Lateral sacral artery
Additional images
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https://en.wikipedia.org/wiki/Buccal%20artery
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The buccal artery (buccinator artery) is a small artery in the head. It branches off the second part of the maxillary artery and supplies the cheek and buccinator muscle.
Course
It runs obliquely forward, between the pterygoideus internus and the insertion of the temporalis, to the outer surface of the buccinator, to which it is distributed, anastomosing with branches of the facial artery and with the infraorbital. From the infraorbital area, it descends bilaterally in the superficial face along the lateral margin of the nose, then running anti-parallel to the facial artery across the lateral oral region.
Additional images
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https://en.wikipedia.org/wiki/Right%20colic%20artery
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The right colic artery is an artery of the abdomen, a branch of the superior mesenteric artery supplying the ascending colon. It divides into two terminal branches - an ascending branch and a descending branch - which form anastomoses with the middle colic artery, and ileocolic artery (respectively).
The right colic artery may be removed during a right hemicolectomy.
Structure
The right colic artery is a relatively small and variable artery. It affords arterial supply to the ascending colon.
Origin
The right colic artery is a branch of the superior mesenteric artery. It usually arises from a common trunk with the middle colic artery, but may also arise directly from the superior mesenteric artery, or from the ileocolic artery.
Course
It passes right-ward posterior to the peritoneum, and anterior to the right gonadal vessels, the right ureter, the psoas major muscle, passing toward the middle of the ascending colon.
Sometimes, it lies at a higher level, and crosses the descending part of the duodenum and the inferior extremity of the right kidney.
At the colon, it divides into a descending branch and an ascending branch. These branches form arches, from the convexity of which vessels are distributed to the ascending colon.
Branches and anastomoses
The descending branch anastomoses with the ileocolic artery.
The ascending branch anastomoses with the middle colic artery.
Variation
The right colic artery is quite variable. It is absent in around 10% of individuals.
Clinical significance
In a right hemicolectomy to remove the caecum and the ascending colon, the right colic artery is ligated and removed. Ligation is performed close to the origin of the right colic artery from the superior mesenteric artery.
If part of the superior mesenteric artery is missing due to a congenital abnormality, the right colic artery may supply part of the ileum.
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https://en.wikipedia.org/wiki/Transverse%20cervical%20artery
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The transverse cervical artery (transverse artery of neck or transversa colli artery) is an artery in the neck and a branch of the thyrocervical trunk, running at a higher level than the suprascapular artery.
Structure
It passes transversely below the inferior belly of the omohyoid muscle to the anterior margin of the trapezius, beneath which it divides into a superficial and a deep branch.
It crosses in front of the phrenic nerve and the scalene muscles, and in front of or between the divisions of the brachial plexus, and is covered by the platysma and sternocleidomastoid muscles, and crossed by the omohyoid and trapezius.
The transverse cervical artery originates from the thyrocervical trunk, it passes through the posterior triangle of the neck to the anterior border of the levator scapulae muscle, where it divides into deep and superficial branches.
Superficial branch
Ascending branch
Descending branch (also known as superficial cervical artery, which supplies the middle and lateral portions of the trapezius)
Deep branch (also called the dorsal scapular artery). Descending branch in older literature. Most often, however, this artery branches directly from the subclavian artery.
Function
Superficial branch
Upon entering the trapezius muscle the superficial branch divides again into an ascending and descending branch. The ascending branch distributes branches to trapezius, and to the neighboring muscles and lymph glands in the neck, and anastomoses with the superficial branch of the descending branch of the occipital artery. The descending branch which is also called as superficial cervical artery, anastomoses with the deep and dorsal scapular artery which in turn links to the subscapular artery. This anastomosis is a ring circulation around the scapula where it continues to the suprascapular artery via the circumflex scapular artery.
Deep branch
The dorsal scapular artery (or descending scapular artery) is a blood vessel which supplies the
levator scap
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https://en.wikipedia.org/wiki/Esophageal%20branches%20of%20thoracic%20part%20of%20aorta
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The esophageal arteries four or five in number, arise from the front of the aorta, and pass obliquely downward to the esophagus, forming a chain of anastomoses along that tube, anastomosing with the esophageal branches of the inferior thyroid arteries above, and with ascending branches from the left inferior phrenic and left gastric arteries below. These arteries supply the middle third of the esophagus.
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https://en.wikipedia.org/wiki/Middle%20genicular%20artery
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The middle genicular artery (azygos articular artery) is a small branch of the popliteal artery. It supplies parts of the knee joint.
Structure
The middle genicular artery (MGA) arises from the anterolateral surface of the popliteal artery. This point of origin is distal to the superior genicular arteries, and between, equidistantly, the medial condyle of femur and the lateral condyle of femur. As a normal variation, the MGA may emerge from the popliteal artery at a common point of origin shared with the superior lateral genicular artery, or both vessels may arise at separate, distinct points.
The angle at which the middle genicular artery leaves the popliteal artery varies with flexion and extension of the knee. It may form a near 90° angle when the knee is flexed, but an angle of only between 15° and 30° when the knee is extended.
The diameter of the MGA is between , and its length between . It has two venae comitantes along its length. It pierces the oblique popliteal ligament and the joint capsule of the knee.
Function
The middle genicular artery supplies the anterior cruciate ligament and the posterior cruciate ligament. It also supplies the synovial membrane at the bottom of the knee.
Clinical significance
The middle genicular artery may be damaged during knee arthroscopy, particularly using a posterior approach through the popliteal fossa. It may also be damaged in traumatic injuries to the knee, often caused by sports.
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https://en.wikipedia.org/wiki/Superior%20genicular%20arteries
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The superior genicular arteries (superior articular arteries), two in number, arise one on either side of the popliteal artery, and wind around the femur immediately above its condyles to the front of the knee-joint. The medial superior genicular artery is on the inside of the knee and the lateral superior genicular artery is on the outside.
Gallery
See also
Patellar anastomosis
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https://en.wikipedia.org/wiki/Lateral%20superior%20genicular%20artery
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The lateral superior genicular artery is a branch of the popliteal artery that supplies a portion of the knee joint.
Anatomy
Course and relations
It passes above the lateral condyle of the femur. It runs deep to the tendon of the biceps femoris.
Branches
It divides into a superficial and a deep branch; the superficial branch supplies the vastus lateralis, and anastomoses with the descending branch of the lateral femoral circumflex and the lateral inferior genicular arteries; the deep branch supplies the lower part of the femur and knee-joint, and forms an anastomotic arch across the front of the bone with the highest genicular and the medial inferior genicular arteries.
Additional images
See also
Patellar anastomosis
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https://en.wikipedia.org/wiki/Medial%20superior%20genicular%20artery
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The medial superior genicular artery is a branch of the popliteal artery. It runs deep to the semimembranosus, semitendinosus, and tendon of the adductor magnus, and superior to the medial head of the gastrocnemius.
It divides into two branches, one of which supplies the vastus medialis, anastomosing with the highest genicular and medial inferior genicular arteries; the other ramifies close to the surface of the femur, supplying it and the knee-joint, and anastomosing with the lateral superior genicular artery.
The medial superior genicular artery is frequently of small size, a condition which is associated with an increase in the size of the highest genicular.
See also
Patellar anastomosis
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https://en.wikipedia.org/wiki/Inferior%20genicular%20arteries
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The inferior genicular arteries (inferior articular arteries), two in number, arise from the popliteal beneath the gastrocnemius. On the inside of the knee, is the medial inferior genicular artery, and on the outer side is the lateral inferior genicular artery.
See also
Patellar anastomosis
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https://en.wikipedia.org/wiki/Lateral%20inferior%20genicular%20artery
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The lateral inferior genicular is an artery of the leg.
Course
It runs lateralward above the head of the fibula to the front of the knee-joint, passing in its course beneath the lateral head of the gastrocnemius, the fibular collateral ligament, and the tendon of the biceps femoris.
Branching
It ends by dividing into branches, which anastomose with the Inferior medial genicular and superior lateral genicular arteries, and with the anterior recurrent tibial artery.
See also
Patellar anastomosis
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https://en.wikipedia.org/wiki/Medial%20inferior%20genicular%20artery
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The medial inferior genicular is an artery of the leg.
Course
It first descends along the upper margin of the popliteus, to which it gives branches; it then passes below the medial condyle of the tibia, beneath the tibial collateral ligament, at the anterior border of which it ascends to the front and medial side of the joint, to supply the upper end of the tibia and the knee-joint, anastomosing with the lateral inferior and medial superior genicular arteries.
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https://en.wikipedia.org/wiki/Short%20gastric%20arteries
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The short gastric arteries are of 5-7 small branches of the splenic artery that pass along part of the greater curvature of the stomach from left to right between the layers of the gastrolienal ligament, and are distributed to the greater curvature of the stomach.
Structure
Origin
The short gastric arteries arise from the end of the splenic artery and its terminal divisions.
Distribution
The short gastric arteries supply the fundus of the stomach on the side of the greater curvature of the stomach.
Anastomoses
The short gastric arteries form anastomoses with branches of the left gastric artery, and left gastro-omental artery.
Unlike the gastroepiploics and the left and right gastric arteries, the short gastric arteries have poor anastomoses if the splenic artery is blocked.
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https://en.wikipedia.org/wiki/Right%20gastric%20artery
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The right gastric artery usually arises from the proper hepatic artery. It descends to the pyloric end of the stomach before passing from right to left along its lesser curvature, supplying it with branches, and finally anastomosing with the left gastric artery.
Anatomy
Variation
Origin
In most (53%) individuals, the RGA arises from the proper hepatic artery. It can also arise from the region of division of the common hepatic artery (20%), the left branch of the hepatic artery (15%), the gastroduodenal artery (8%), and - most rarely - the common hepatic artery itself (4%).
Additional images
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https://en.wikipedia.org/wiki/Inferior%20thyroid%20artery
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The inferior thyroid artery is an artery in the neck. It arises from the thyrocervical trunk and passes upward, in front of the vertebral artery and longus colli muscle. It then turns medially behind the carotid sheath and its contents, and also behind the sympathetic trunk, the middle cervical ganglion resting upon the vessel.
Reaching the lower border of the thyroid gland it divides into two branches, which supply the postero-inferior parts of the gland, and anastomose with the superior thyroid artery, and with the corresponding artery of the opposite side.
Structure
The branches of the inferior thyroid artery are the inferior laryngeal, the oesophageal, the tracheal, the ascending cervical and the pharyngeal arteries.
Branches
Inferior laryngeal artery
The inferior laryngeal artery - accompanied by the recurrent laryngeal nerve - passes superior-ward upon the trachea deep to the inferior pharyngeal constrictor muscle to reach the posterior surface of the larynx. At the inferior border of the inferior pharyngeal constrictor muscle, the artery enters the larynx.
The artery supplies the muscles and mucosa of the larynx.
It forms anastomoses with its contralateral partner, and the superior laryngeal branch of the superior thyroid artery.
Tracheal branches
The tracheal branches are distributed on the trachea, and anastomose inferiorly with the bronchial arteries.
Esophageal branches
The esophageal branches supply the esophagus, and anastomose with the esophageal branches of the thoracic aorta.
Ascending cervical artery
The ascending cervical artery is a small branch which arises from the inferior thyroid artery as it turns medial-ward posterior to the carotid sheath.
The artery ascends upon the anterior tubercles of the transverse processes of the cervical vertebrae between the anterior scalene muscle and longus capitis muscle.
The ascending cervical artery gives twigs to the neck muscles and these anastomose with branches of the vertebral arteries. On
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https://en.wikipedia.org/wiki/Transverse%20facial%20artery
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The transverse facial artery is an artery that branches from the superficial temporal artery and runs across the face.
Course
The transverse facial artery is given off from the superficial temporal artery before that vessel leaves the parotid gland; running forward through the substance of the gland, it passes transversely across the side of the face, between the parotid duct and the lower border of the zygomatic arch, and divides into numerous branches, which supply the parotid gland and parotid duct, the masseter muscle, and the integument, and anastomose with the facial artery, the masseteric artery, the buccinator artery, and the infraorbital artery.
This vessel rests on the masseter, and is accompanied by one or two branches of the facial nerve.
Additional images
See also
Facial artery
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https://en.wikipedia.org/wiki/Ileocolic%20artery
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The ileocolic artery is the lowest branch arising from the concavity of the superior mesenteric artery. It supplies the cecum, ileum, and appendix.
It passes downward and to the right behind the peritoneum toward the right iliac fossa, where it divides into a superior and an inferior branch: the inferior gives rise to the appendicular artery and anastomoses with the end of the superior mesenteric artery; the superior branch anastomoses with the right colic artery.
Anatomy
Branches
The inferior branch of the ileocolic runs toward the upper border of the ileocolic junction and produces the following branches:
colic branch of ileocolic artery, which passes upward on the ascending colon - from the posterior branch of the inferior branch of the ileocolic artery
ileocecal (some sources acknowledge this division while others do not)
anterior cecal artery and posterior cecal artery, which are distributed to the front and back of the cecum
ileal branch of ileocolic artery, which runs upward and to the left on the lower part of the ileum and anastomoses with the termination of the superior mesenteric artery
an appendicular artery
Additional images
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https://en.wikipedia.org/wiki/Ileocolic
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In many Animalia, including humans, an ileocolic structure or problem is something that concerns the region of the gastrointestinal tract from the ileum to the colon. In Animalia that have ceca, the ileocecal region is a subset of the ileocolic region, and the entire range can also be described as ileocecocolic, whereas in some Animalia, the ileocolic region contains no cecum, as the ileum joins the colon directly.
Things that are ileocolic, ileocecal, or both include the following:
Ileocecal fold
Ileocecal/ileocolic intussusception
Ileocecal valve
Ileocolic artery
Ileocolic lymph nodes
Ileocolic vein
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https://en.wikipedia.org/wiki/Inferior%20alveolar%20artery
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The inferior alveolar artery (inferior dental artery) is an artery of the head. It is a branch of (the first part of) the maxillary artery. It descends through the infratemporal fossa as part of a neurovascular bundle with the inferior alveolar nerve and vein to the mandibular foramen where it enters and passes anterior-ward inside the mandible, suplying the body of mandible and the dental pulp of the lower molar and premolar teeth. Its terminal incisor branch supplies the rest of the lower teeth. Its mental branch exits the mandibula anteriorly through the mental foramen to supply adjacent lip and skin.
Structure
Course
It passes inferior-ward through the infratemporal fossa as part of a neurovascular bundle with the inferior alveolar nerve and vein to the mandibular foramen. In the infratemporal fossa, it is situated posterior to the inferior alveolar nerve, lateral to the skull, and medial to the sphenomandibular ligament.
It enters the mandibular foramen (of the medial surface of the ramus of the mandible) to come to pass anterior-ward within the mandibular canal alongside the inferior alveolar nerve. Within the canal, it provides arterial supply to the mandibular/lower molar and premolar teeth before splitting into its two terminal branches (incisive branch and mental branch) close to the first premolar.
Branches
The inferior alveolar artery and its incisor branch during their course through mandibular canal issue a few twigs which are lost in the cancellous tissue, and a series of branches which correspond in number to the number of the roots of the teeth: these enter the minute apertures at the extremities of the roots of the teeth to supply the pulp of the teeth.
Lingual branch
Near to its origin, the inferior alveolar artery issues a lingual branch which passes inferior-ward alongside the lingual nerve. It provides arterial supply to the mucous membrane of the tongue.
Incisor branch
The incisor branch is continued anterior-ward inferior to the inc
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https://en.wikipedia.org/wiki/Lateral%20circumflex%20femoral%20artery
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The lateral circumflex femoral artery (also known as the lateral femoral circumflex artery, or the external circumflex artery) is an artery in the upper thigh. It is usually a branch of the profunda femoris artery, and produces three branches. It is mostly distributed to the muscles of the lateral thigh, supplying arterial blood to muscles of the knee extensor group.
Structure
Origin
The lateral femoral circumflex artery usually arises from the lateral side of the profunda femoris artery, but may occasionally arise directly from the femoral artery. It is the largest branch of the profunda femoris artery.
Course and relations
The lateral circumflex femoral artery usually courses anterior to the femoral neck. It passes horizontally between the divisions of the femoral nerve. It passes posterior to the sartorius muscle and rectus femoris muscle. It passes laterally across the hip joint capsule.
It divides into ascending, transverse, and descending branches.
Branches
The lateral circumflex femoral artery has three branches:
The ascending branch of lateral circumflex femoral artery passes upward, beneath the tensor fasciae latae muscle, to the lateral aspect of the hip, and anastomoses with the terminal branches of the superior gluteal and deep circumflex iliac artery.
The descending branch of lateral circumflex femoral artery runs downward, behind the rectus femoris, upon the vastus lateralis, to which it gives offsets; one long branch descends in the muscle as far as the knee, and anastomoses with the superior lateral genicular artery. It is accompanied by the branch of the femoral nerve to the vastus lateralis muscle.
The transverse branch of lateral circumflex femoral artery is a small artery in the thigh. It is the smallest branch of the lateral circumflex femoral artery and passes lateralward over the vastus intermedius, pierces the vastus lateralis, and winds around the femur, just below the greater trochanter, anastomosing on the back of the thigh with
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https://en.wikipedia.org/wiki/Medial%20circumflex%20femoral%20artery
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The medial circumflex femoral artery (internal circumflex artery, medial femoral circumflex artery) is an artery in the upper thigh that arises from the profunda femoris artery. It supplies arterial blood to several muscles in the region, as well as the femoral head and neck.
Damage to the artery following a femoral neck fracture may lead to avascular necrosis (ischemic) of the femoral neck/head.
Structure
Origin
The medial femoral circumflex artery arises from the posteromedial aspect of the profunda femoris artery.
The medial femoral circumflex artery may occasionally arise directly from the femoral artery.
Course and relations
It winds around the medial side of the femur to pass along the posterior aspect of the femur. It first passes between the pectineus and the iliopsoas muscles, then between the obturator externus and the adductor brevis muscles.
Branches
At the upper border of the adductor brevis it gives off two branches:
The ascending branch
The descending branch descends beneath the adductor brevis, to supply it and the adductor magnus; the continuation of the vessel passes backward and divides into superficial, deep, and acetabular branches.
The superficial branch
The deep branch
The acetabular branch
Distribution
The medial femoral circumflex artery (with its branches) supplies arterial blood to several muscles, including: the adductor muscles of the hip, gracilis muscle, pectineus muscle, and external obturator muscle. It delivers most of the arterial supply to the femoral head and femoral neck via branches - the posterior retinacular arteries.
Clinical significance
Branches of the medial circumflex femoral artery supplying the head and neck of the femur are often torn in femoral neck fractures and in hip dislocation.
See also
Lateral femoral circumflex artery
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https://en.wikipedia.org/wiki/Anterior%20interosseous%20artery
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The anterior interosseous artery (volar interosseous artery) is an artery in the forearm. It is a branch of the common interosseous artery.
Course
It passes down the forearm on the palmar surface of the interosseous membrane.
It is accompanied by the palmar interosseous branch of the median nerve, and overlapped by the contiguous margins of the flexor digitorum profundus and flexor pollicis longus muscles, giving off in this situation muscular branches, and the nutrient arteries of the radius and ulna.
At the upper border of the pronator quadratus muscle it pierces the interosseous membrane and reaches the back of the forearm, where it anastomoses with the dorsal interosseous artery.
It then descends, in company with the terminal portion of the dorsal interosseous nerve, to the back of the wrist to join the dorsal carpal network.
The anterior interosseous artery may give off a slender branch, the median artery, which accompanies the median nerve, and gives offsets to its substance; this artery is sometimes much enlarged, and runs with the nerve into the palm of the hand.
Before it pierces the interosseous membrane the anterior interosseous sends a branch downward behind the pronator quadratus muscle to join the palmar carpal network.
Function
The anterior interosseous artery supplies the deep layer of the anterior compartment of the forearm, including the flexor digitorum profundus, flexor pollicis longus, and pronator quadratus muscles.
Additional images
See also
Posterior interosseous artery
Ulnar artery
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https://en.wikipedia.org/wiki/Inferior%20labial%20artery
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The inferior labial artery (inferior labial branch of facial artery) arises near the angle of the mouth as a branch of the facial artery; it passes upward and forward beneath the triangularis and, penetrating the orbicularis oris, runs in a tortuous course along the edge of the lower lip between this muscle and the mucous membrane.
It supplies the labial glands, the mucous membrane, and the muscles of the lower lip; and anastomoses with the artery of the opposite side, and with the mental branch of the inferior alveolar artery.
Additional images
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https://en.wikipedia.org/wiki/Superior%20labial%20artery
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The superior labial artery (superior labial branch of facial artery) is larger and more egregious than the inferior labial artery.
It follows a similar course along the edge of the upper lip, lying between the mucous membrane and the orbicularis oris, and anastomoses with the artery of the opposite side.
It supplies the upper lip, and gives off in its course two or three vessels which ascend to the nose; a septal branch ramifies on the nasal septum as far as the point of the nose, and an alar branch supplies the ala of the nose.
See also
Kiesselbach's plexus
Additional images
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https://en.wikipedia.org/wiki/Ascending%20pharyngeal%20artery
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The ascending pharyngeal artery is an artery of the neck that supplies the pharynx.
Its named branches are the inferior tympanic artery, pharyngeal artery, and posterior meningeal artery. inferior tympanic artery, and the meningeal branches (including the posterior meningeal artery).
Anatomy
The ascending pharyngeal artery is a long and slender vessel.
It is deeply seated in the neck, beneath the other branches of the external carotid and under the stylopharyngeus muscle. It lies just superior to the bifurcation of the common carotid arteries.
Origin
It is the first (and smallest) branch of (the proximal part of) the external carotid artery. It arises from the medial (deep) surface of the vessel.
Course and relations
The artery ascends vertically in between the internal carotid artery and the pharynx to reach the base of the skull.
The artery is crossed by the styloglossus muscle and stylopharyngeus muscle. The longus capitis muscle is situated posterior to the artery.
Branches
The artery most typically bifurcates into embryologically distinct pharyngeal and neuromeningeal trunks.
The pharyngeal trunk usually consists of several branches which supply the middle and inferior pharyngeal constrictor muscles and the stylopharyngeus, ramifying in their substance and in the mucous membranes lining them. These branches are in hemodynamic equilibrium with contributors from the internal maxillary artery. The neuromeningeal trunk classically consists of jugular and hypoglossal divisions, which enter the jugular and hypoglossal foramina to supply regional meningeal and neural structures, being in equilibrium with branches of the vertebral, occipital, posterior meningeal, middle meningeal, and internal carotid arteries (via its caroticotympanic branch, meningohypophyseal, and inferolateral trunks). Also present is the inferior tympanic branch, which ascends towards the middle ear cavity; it is involved in internal carotid artery reconstitution via the "aberrant c
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https://en.wikipedia.org/wiki/Superficial%20palmar%20arch
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The superficial palmar arch is formed predominantly by the ulnar artery, with a contribution from the superficial palmar branch of the radial artery. However, in some individuals the contribution from the radial artery might be absent, and instead anastomoses with either the princeps pollicis artery, the radialis indicis artery, or the median artery, the former two of which are branches from the radial artery.
Alternative names for this arterial arch are: superficial volar arch, superficial ulnar arch, arcus palmaris superficialis, or arcus volaris superficialis.
The arch passes across the palm in a curve (Boeckel's line) with its convexity downward,
If one were to fully extend the thumb, the superficial palmar arch would lie approximately 1 cm distal from a line drawn between the first web space to the Hook of Hamate (Kaplan's Cardinal Line). The superficial palmar arch extends more distally than the deep palmar arch. The connection between the deep and superficial palmar arterial arches is an example of anastomosis, and can be tested for using Allen's test.
Three common palmar digital arteries arise from the arch, proceeding down on the second, third, and fourth lumbrical muscles, respectively. They each receive a contribution from a palmar metacarpal artery. Near the level of the metacarpophalangeal joints, each common palmar digital artery divides into two proper palmar digital arteries.
Four digital branches arise from this palmar arch that supplies the medial/ulnar 3 1/2 fingers.
See also
Deep palmar arch
Palmar carpal arch
Dorsal carpal arch
Additional images
Footnotes and references
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https://en.wikipedia.org/wiki/Lumbar%20arteries
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The lumbar arteries are arteries located in the lower back or lumbar region. The lumbar arteries are in parallel with the intercostals.
They are usually four in number on either side, and arise from the back of the aorta, opposite the bodies of the upper four lumbar vertebrae.
A fifth pair, small in size, is occasionally present: they arise from the middle sacral artery.
They run lateralward and backward on the bodies of the lumbar vertebrae, behind the sympathetic trunk, to the intervals between the adjacent transverse processes, and are then continued into the abdominal wall.
The arteries of the right side pass behind the inferior vena cava, and the upper two on each side run behind the corresponding crus of the diaphragm.
The arteries of both sides pass beneath the tendinous arches which give origin to the psoas major, and are then continued behind this muscle and the lumbar plexus.
They now cross the quadratus lumborum, the upper three arteries running behind, the last usually in front of the muscle.
At the lateral border of the quadratus lumborum they pierce the posterior aponeurosis of the transversus abdominis and are carried forward between this muscle and the obliquus internus.
They anastomose with the lower intercostal, the subcostal, the iliolumbar, the deep iliac circumflex, and the inferior epigastric arteries.
Additional images
See also
Lumbar veins
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https://en.wikipedia.org/wiki/Pericardiacophrenic%20artery
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The pericardiacophrenic artery is a long slender branch of the internal thoracic artery.
Anatomy
Origin
The pericardiacophrenic artery branches from the internal thoracic artery.
Course
The pericardiacophrenic arteries travel through the thoracic cavity. They course through the fibrous pericardium. The pericardiacophrenic artery accompanies the phrenic nerve between the pleura and pericardium, to the diaphragm. This is where both the artery and the phrenic nerve are distributed.
Distribution
The pericardiacophrenic arteries provide arterial supply to the fibrous pericardium, and (along with the musculophrenic arteries) the diaphragm.
Anastomoses
It anastomoses with the musculophrenic, and superior phrenic arteries.
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https://en.wikipedia.org/wiki/Intestinal%20arteries
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The intestinal arteries arise from the convex side of the superior mesenteric artery. They are usually from twelve to fifteen in number, and are distributed to the jejunum and ileum.
Nomenclature
The term "intestinal arteries" can be confusing, because these arteries only serve a small portion of the intestines.
They do not supply any of the large intestine. The large intestine is primarily supplied by the right colic artery, middle colic artery, and left colic artery.
They do not supply the duodenum of the small intestine. The duodenum is primarily supplied by the inferior pancreaticoduodenal artery and superior pancreaticoduodenal artery.
For clarity, some sources prefer instead using the more specific terms ileal arteries and jejunal arteries.
Path
They run nearly parallel with one another between the layers of the mesentery, each vessel dividing into two branches, which unite with adjacent branches, forming a series of arches (arterial arcades), the convexities of which are directed toward the intestine.
From this first set of arches branches arise, which unite with similar branches from above and below and thus a second series of arches is formed; from the lower branches of the artery, a third, a fourth, or even a fifth series of arches may be formed, diminishing in size the nearer they approach the intestine.
In the short, upper part of the mesentery only one set of arches exists, but as the depth of the mesentery increases, second, third, fourth, or even fifth groups are developed.
The differences between the ileal arteries and the jejunal arteries can be summarized as follows:
From the terminal arches numerous small straight vessels (vasa recta) arise which encircle the intestine, upon which they are distributed, ramifying between its coats.
From the intestinal arteries small branches are given off to the lymph glands and other structures between the layers of the mesentery.
Additional images
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https://en.wikipedia.org/wiki/Inferior%20pancreaticoduodenal%20artery
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The inferior pancreaticoduodenal artery (the IPDA) is a branch of the superior mesenteric artery. It supplies the head of the pancreas, and the ascending and inferior parts of the duodenum. Rarely, it may have an aneurysm.
Structure
The inferior pancreaticoduodenal artery is a branch of the superior mesenteric artery. This occurs opposite the upper border of the inferior part of the duodenum. As soon as it branches, it divides into anterior and posterior branches. These run between the head of the pancreas and the lesser curvature of the duodenum. They then join (anastomose) with the anterior and posterior branches of the superior pancreaticoduodenal artery.
Variation
The inferior pancreaticoduodenal artery may branch from the first intestinal branch of the superior mesenteric artery rather than directly from it.
Function
The inferior pancreaticoduodenal artery distributes branches to the head of the pancreas and to the ascending and inferior parts of the duodenum.
Clinical significance
Aneurysm
Very rarely, the inferior pancreaticoduodenal artery may have an aneurysm. It may be caused by certain medical interventions, major trauma, pancreatitis, cholecystitis, and vasculitis and other infections. A ruptured aneurysm causes abdominal pain, and haemorrhage leads to hypotension. It may be treated with open abdominal surgery. It may also be treated with endovascular surgery, such as a coil. These aneurysms represent around 2% of aneurysms in visceral arteries of the abdomen. Pseudoaneurysm may also occur.
History
The inferior pancreaticoduodenal artery may be more simply known by the acronym IPDA.
Additional images
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https://en.wikipedia.org/wiki/Deep%20palmar%20arch
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The deep palmar arch (deep volar arch) is an arterial network found in the palm. It is usually primarily formed from the terminal part of the radial artery. The ulnar artery also contributes through an anastomosis. This is in contrast to the superficial palmar arch, which is formed predominantly by the ulnar artery.
Structure
The deep palmar arch is usually primarily formed from the radial artery. The ulnar artery also contributes through an anastomosis.
The deep palmar arch lies upon the bases of the metacarpal bones and on the interossei of the hand. It is deep to the oblique head of the adductor pollicis muscle, the flexor tendons of the fingers, and the lumbricals of the hand.
Alongside of it, but running in the opposite direction—toward the radial side of the hand—is the deep branch of the ulnar nerve.
The superficial palmar arch is more distally located than the deep palmar arch. If one were to fully extend the thumb and draw a line from the distal border of the thumb across the palm, this would be the level of the superficial palmar arch (Boeckel's line). The deep palmar arch is about a finger width proximal to this. The connection between the deep and superficial palmar arterial arches is an example of anastomosis. This anastomosis can be tested for using Allen's test.
The palmar metacarpal arteries arise from the deep palmar arch.
Function
The deep palmar arch supplies the thumb and the lateral side of the index finger.
See also
Superficial palmar arch
Palmar carpal arch
Dorsal carpal arch
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https://en.wikipedia.org/wiki/Lowry%20protein%20assay
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The Lowry protein assay is a biochemical assay for determining the total level of protein in a solution. The total protein concentration is exhibited by a color change of the sample solution in proportion to protein concentration, which can then be measured using colorimetric techniques. It is named for the biochemist Oliver H. Lowry who developed the reagent in the 1940s. His 1951 paper describing the technique is the most-highly cited paper ever in the scientific literature, cited over 300,000 times.
Mechanism
The method combines the reactions of copper ions with the peptide bonds under alkaline conditions (the Biuret test) with the oxidation of aromatic protein residues. The Lowry method is based on the reaction of Cu+, produced by the oxidation of peptide bonds, with Folin–Ciocalteu reagent (a mixture of phosphotungstic acid and phosphomolybdic acid in the Folin–Ciocalteu reaction). The reaction mechanism is not well understood, but involves reduction of the Folin–Ciocalteu reagent and oxidation of aromatic residues (mainly tryptophan, also tyrosine). Experiments have shown that cysteine is also reactive to the reagent. Therefore, cysteine residues in protein probably also contribute to the absorbance seen in the Lowry assay. The result of this reaction is an intense blue molecule known as heteropolymolybdenum Blue. The concentration of the reduced Folin reagent (heteropolymolybdenum Blue) is measured by absorbance at 660 nm. As a result, the total concentration of protein in the sample can be deduced from the concentration of tryptophan and tyrosine residues that reduce the Folin–Ciocalteu reagent.
The method was first proposed by Lowry in 1951. The bicinchoninic acid assay and the Hartree–Lowry assay are subsequent modifications of the original Lowry procedure.
See also
Biuret test
Bradford protein assay
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https://en.wikipedia.org/wiki/Kernel%20Transaction%20Manager
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Kernel Transaction Manager (KTM) is a component of the Windows operating system kernel in Windows Vista and Windows Server 2008 that enables applications to use atomic transactions on resources by making them available as kernel objects.
Overview
The transaction engine, which operates in kernel mode, allows for transactions on both kernel mode and user mode resources, as well as among distributed resources. The Kernel Transaction Manager intends to make it easy for application developers to do much error recovery, virtually transparently, with KTM acting as a transaction manager that transaction clients can plug into. Those transaction clients can be third-party clients that want to initiate transactions on resources that are managed by Transaction Resource Manager. The resource managers can also be third-party or built into the system.
KTM is used to implement Transactional NTFS (TxF) and Transactional Registry (TxR). KTM relies on the Common Log File System (CLFS) for its operation. CLFS is a general-purpose log-file subsystem designed for creating data and event logs.
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https://en.wikipedia.org/wiki/Noshi
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are a kind of ceremonial origami fold entirely distinct from "origami-tsuki". They serve as gifts that express "good wishes". Noshi consists of white paper folded with a strip of dried abalone or meat, considered a token of good fortune.
See also
Shūgi-bukuro
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https://en.wikipedia.org/wiki/Fundamental%20matrix%20%28computer%20vision%29
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In computer vision, the fundamental matrix is a 3×3 matrix which relates corresponding points in stereo images. In epipolar geometry, with homogeneous image coordinates, x and x′, of corresponding points in a stereo image pair, Fx describes a line (an epipolar line) on which the corresponding point x′ on the other image must lie. That means, for all pairs of corresponding points holds
Being of rank two and determined only up to scale, the fundamental matrix can be estimated given at least seven point correspondences. Its seven parameters represent the only geometric information about cameras that can be obtained through point correspondences alone.
The term "fundamental matrix" was coined by QT Luong in his influential PhD thesis. It is sometimes also referred to as the "bifocal tensor". As a tensor it is a two-point tensor in that it is a bilinear form relating points in distinct coordinate systems.
The above relation which defines the fundamental matrix was published in 1992 by both Olivier Faugeras and Richard Hartley. Although H. Christopher Longuet-Higgins' essential matrix satisfies a similar relationship, the essential matrix is a metric object pertaining to calibrated cameras, while the fundamental matrix describes the correspondence in more general and fundamental terms of projective geometry.
This is captured mathematically by the relationship between a fundamental matrix
and its corresponding essential matrix ,
which is
and being the intrinsic calibration
matrices of the two images involved.
Introduction
The fundamental matrix is a relationship between any two images of the same scene that constrains where the projection of points from the scene can occur in both images. Given the projection of a scene point into one of the images the corresponding point in the other image is constrained to a line, helping the search, and allowing for the detection of wrong correspondences. The relation between corresponding points, which the fundamental
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https://en.wikipedia.org/wiki/Chlorosome
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A chlorosome is a photosynthetic antenna complex found in green sulfur bacteria (GSB) and many green non-sulfur bacteria (GNsB), together known as green bacteria. They differ from other antenna complexes by their large size and lack of protein matrix supporting the photosynthetic pigments. Green sulfur bacteria are a group of organisms that generally live in extremely low-light environments, such as at depths of 100 metres in the Black Sea. The ability to capture light energy and rapidly deliver it to where it needs to go is essential to these bacteria, some of which see only a few photons of light per chlorophyll per day. To achieve this, the bacteria contain chlorosome structures, which contain up to 250,000 chlorophyll molecules. Chlorosomes are ellipsoidal bodies, in GSB their length varies from 100 to 200 nm, width of 50-100 nm and height of 15 – 30 nm, in GNsB the chlorosomes are somewhat smaller.
Structure
Chlorosome shape can vary between species, with some species containing ellipsoidal shaped chlorosomes and others containing conical or irregular shaped chlorosomes.
Inside green sulfur bacteria, the chlorosomes are attached to type-I reaction centers in the cell membrane via FMO-proteins and a chlorosome baseplate composed of CsmA proteins. Filamentous anoxygenic phototrophs of the phylum Chloroflexota lack the FMO complex, but instead use a protein complex called B808-866. Unlike the FMO proteins in green sulfur bacteria, B808-866 proteins are embedded in the cytoplasmic membrane and surround type-II reaction centers, providing the link between the reaction centers and the baseplate.
The composition of the chlorosomes is mostly bacteriochlorophyll (BChl) with small amounts of carotenoids and quinones surrounded by a galactolipid monolayer. In Chlorobi, chlorosome monolayers can contain up to eleven different proteins. The proteins of Chlorobi are the ones currently best understood in terms of structure and function. These proteins are named CsmA thr
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https://en.wikipedia.org/wiki/TCP%20sequence%20prediction%20attack
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A TCP sequence prediction attack is an attempt to predict the sequence number used to identify the packets in a TCP connection, which can be used to counterfeit packets.
The attacker hopes to correctly guess the sequence number to be used by the sending host. If they can do this, they will be able to send counterfeit packets to the receiving host which will seem to originate from the sending host, even though the counterfeit packets may in fact originate from some third host controlled by the attacker. One possible way for this to occur is for the attacker to listen to the conversation occurring between the trusted hosts, and then to issue packets using the same source IP address. By monitoring the traffic before an attack is mounted, the malicious host can figure out the correct sequence number. After the IP address and the correct sequence number are known, it is basically a race between the attacker and the trusted host to get the correct packet sent. One common way for the attacker to send it first is to launch another attack on the trusted host, such as a denial-of-service attack. Once the attacker has control over the connection, they are able to send counterfeit packets without getting a response.
If an attacker can cause delivery of counterfeit packets of this sort, they may be able to cause various sorts of mischief, including the injection into an existing TCP connection of data of the attacker's choosing, and the premature closure of an existing TCP connection by the injection of counterfeit packets with the RST bit set, a TCP reset attack.
Theoretically, other information such as timing differences or information from lower protocol layers could allow the receiving host to distinguish authentic TCP packets from the sending host and counterfeit TCP packets with the correct sequence number sent by the attacker. If such other information is available to the receiving host, if the attacker can also fake that other information, and if the receiving host ga
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https://en.wikipedia.org/wiki/Operation%20Stella%20Polaris
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Operation Stella Polaris was the cover name for an operation in which Finnish signals intelligence records, equipment and personnel were transported to Sweden in late September 1944 after the end of combat on the Finnish-Soviet front in the Second World War. The purpose was to enable the signals intelligence activities against the advancing Russians to continue in Sweden and to prevent the equipment falling into the hands of the Soviet Union. A Soviet invasion was considered likely and plans were made to support guerrilla warfare in Finland after a possible occupation. The operation had its base in the small fishing village of Nämpnäs in Närpes, Ostrobothnia region, from where the archives were shipped to Swedish ports. The leaders of the operation were Colonel Aladár Paasonen, chief of Finnish military intelligence, and Colonel Reino Hallamaa, head of the Finnish signals intelligence section.
Transportation to Sweden
On 20September 1944 a large part of the Finnish signals intelligence unit was moved to Sweden. From the Swedish side Major Carl Petersén, head of the Defence Staff's intelligence section C-byrån, was responsible for the operation. Approximately 750 people were transported across the Gulf of Bothnia: by three ships from Närpes to Härnösand; and one ship from Uusikaupunki to Gävle. The ships also carried boxes of archives and signals intelligence equipment.
After the Soviet Union was ceded parts of Karelia and Salla from Finland on 19September 1944, in accord with the Moscow Armistice, the majority of the Finnish personnel and their families returned home, except those hired by Sweden's National Defence Radio Establishment (FRA). They crossed the border at the Torne River in secret. Sweden offered to take over the equipment and some of the documents. The FRA thus had access to technical equipment and seven boxes of files, which became important in the newly established activities of the FRA.
Operation Stella Polaris led to Sweden gaining access to a l
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https://en.wikipedia.org/wiki/Sizeof
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sizeof is a unary operator in the programming languages C and C++. It generates the storage size of an expression or a data type, measured in the number of char-sized units. Consequently, the construct sizeof (char) is guaranteed to be 1. The actual number of bits of type char is specified by the preprocessor macro , defined in the standard include file limits.h. On most modern computing platforms this is eight bits. The result of sizeof has an unsigned integer type that is usually denoted by size_t.
The operator has a single operand, which is either an expression or the cast of a data type, which is a data type enclosed in parentheses. Data types may not only be primitive types, such as integer and floating-point types, but also pointer types, and compound datatypes (unions, structs, and C++ classes).
Purpose
Many programs must know the storage size of a particular datatype. Though for any given implementation of C or C++ the size of a particular datatype is constant, the sizes of even primitive types in C and C++ may be defined differently for different platforms of implementation. For example, runtime allocation of array space may use the following code, in which the sizeof operator is applied to the cast of the type int:
int *pointer = malloc(10 * sizeof (int));
In this example, function malloc allocates memory and returns a pointer to the memory block. The size of the block allocated is equal to the number of bytes for a single object of type int multiplied by 10, providing space for ten integers.
It is generally not safe to assume the size of any datatype. For example, even though most implementations of C and C++ on 32-bit systems define type int to be four octets, this size may change when code is ported to a different system, breaking the code. The exception to this is the data type char, which always has the size 1 in any standards-compliant C implementation. In addition, it is frequently difficult to predict the sizes of compound datatypes such as
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https://en.wikipedia.org/wiki/Ochratoxin%20A
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Ochratoxin A—a toxin produced by different Aspergillus and Penicillium species — is one of the most-abundant food-contaminating mycotoxins. It is also a frequent contaminant of water-damaged houses and of heating ducts. Human exposure can occur through consumption of contaminated food products, particularly contaminated grain and pork products, as well as coffee, wine grapes, and dried grapes. The toxin has been found in the tissues and organs of animals, including human blood and breast milk. Ochratoxin A, like most toxic substances, has large species- and sex-specific toxicological differences.
Impact on human and animal health
Carcinogenicity
Ochratoxin A is potentially carcinogenic to humans (Group 2B), and has been shown to be weakly mutagenic, possibly by induction of oxidative DNA damage.
The evidence in experimental animals is sufficient to indicate carcinogenicity of ochratoxin A. It was tested for carcinogenicity by oral administration in mice and rats. It slightly increased the incidence of hepatocellular carcinomas in mice of each sex. and produced renal adenomas and carcinomas in male mice and in rats (carcinomas in 46% of males and 5% of females).
In humans, very little histology data are available, so a relationship between ochratoxin A and renal cell carcinoma has not been found. However, the incidence of transitional cell (urothelial) urinary cancers seems abnormally high in Balkan endemic nephropathy patients, especially for the upper urinary tract.
The molecular mechanism of ochratoxin A carcinogenicity has been under debate due to conflicting literature, however this mycotoxin has been proposed to play a major role in reducing antioxidant defenses.
Neurotoxicity
Ochratoxin A has a strong affinity for the brain, especially the cerebellum (Purkinje cells), ventral mesencephalon, and hippocampal structures. The affinity for the hippocampus could be relevant to the pathogenesis of Alzheimer's disease, and subchronic administration to rodents in
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https://en.wikipedia.org/wiki/Standard%20model%20%28cryptography%29
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In cryptography the standard model is the model of computation in which the adversary is only limited by the amount of time and computational power available. Other names used are bare model and plain model.
Cryptographic schemes are usually based on complexity assumptions, which state that some problems, such as factorization, cannot be solved in polynomial time. Schemes that can be proven secure using only complexity assumptions are said to be secure in the standard model. Security proofs are notoriously difficult to achieve in the standard model, so in many proofs, cryptographic primitives are replaced by idealized versions. The most common example of this technique, known as the random oracle model, involves replacing a cryptographic hash function with a genuinely random function. Another example is the generic group model, where the adversary is given access to a randomly chosen encoding of a group, instead of the finite field or elliptic curve groups used in practice.
Other models used invoke trusted third parties to perform some task without cheating; for example, the public key infrastructure (PKI) model requires a certificate authority, which if it were dishonest, could produce fake certificates and use them to forge signatures, or mount a man in the middle attack to read encrypted messages. Other examples of this type are the common random string model, where it is assumed that all parties have access to some string chosen uniformly at random, and its generalization, the common reference string model, where a string is chosen according to some other probability distribution. These models are often used for non-interactive zero-knowledge proofs (NIZK). In some applications, such as the Dolev–Dwork–Naor encryption scheme, it makes sense for a particular party to generate the common reference string, while in other applications, the common reference string must be generated by a trusted third party. Collectively, these models are referred to as models with
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https://en.wikipedia.org/wiki/Inferior%20mesenteric%20plexus
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The inferior mesenteric plexus is derived chiefly from the aortic plexus.
It surrounds the inferior mesenteric artery, and divides into a number of secondary plexuses, which are distributed to all the parts supplied by the artery, viz., the left colic and sigmoid plexuses, which supply the descending and sigmoid parts of the colon; and the superior hemorrhoidal plexus, which supplies the rectum and joins in the pelvis with branches from the pelvic plexuses.
Additional images
See also
Inferior mesenteric artery
Superior mesenteric plexus
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https://en.wikipedia.org/wiki/Hydraulic%20power%20network
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A hydraulic power network is a system of interconnected pipes carrying pressurized liquid used to transmit mechanical power from a power source, like a pump, to hydraulic equipment like lifts or motors. The system is analogous to an electrical grid transmitting power from a generating station to end-users. Only a few hydraulic power transmission networks are still in use; modern hydraulic equipment has a pump built into the machine. In the late 19th century, a hydraulic network might have been used in a factory, with a central steam engine or water turbine driving a pump and a system of high-pressure pipes transmitting power to various machines.
The idea of a public hydraulic power network was suggested by Joseph Bramah in a patent obtained in 1812. William Armstrong began installing systems in England from the 1840s, using low-pressure water, but a breakthrough occurred in 1850 with the introduction of the hydraulic accumulator, which allowed much higher pressures to be used. The first public network, supplying many companies, was constructed in Kingston upon Hull, England. The Hull Hydraulic Power Company began operation in 1877, with Edward B. Ellington as its engineer. Ellington was involved in most of the British networks, and some further afield. Public networks were constructed in Britain at London, Liverpool, Birmingham, Manchester and Glasgow. There were similar networks in Antwerp, Melbourne, Sydney, Buenos Aires and Geneva. All of the public networks had ceased to operate by the mid-1970s, but Bristol Harbour still has an operational system, with an accumulator situated outside the main pumphouse, enabling its operation to be easily visualised.
History
Joseph Bramah, an inventor and locksmith living in London, registered a patent at the London Patent Office on 29 April 1812, which was principally about a provision of a public water supply network, but included a secondary concept for the provision of a high-pressure water main, which would enable worksh
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https://en.wikipedia.org/wiki/Roman%20pot
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The Roman pot is the name of a technique (and of the relevant device) used in accelerator physics. Named after its implementation by the CERN-Rome collaboration in the early 1970s, it is an important tool to measure the total cross section of two particle beams in a collider. They are called pots because the detectors are housed in cylindrical vessels. The first generation of Roman pots was purpose-built by the CERN Central Workshops and used in the measurement of the total cross-section of proton-proton inter-actions in the ISR.
Roman pots are located as close to the beamline as possible, to capture the accelerated particles which scatter by very small angles.
Roman pots used at the Large Hadron Collider (LHC)
Roman pots were first used in the TOTEM experiment and later by the ATLAS and the CMS collaborations at the LHC. The figure below shows a detector used on the beamline near IP5 (interaction point 5), the location of the CMS detector. Three of these are used per Roman pot unit. Each is shoved into place to within 10 microns of the beamline. Two detectors are placed above and below the beamline, and a third to the side. These detectors will record any protons that are not travelling precisely along the beamline, and thus record the elastic scattering of the protons. This is used to measure the total elastic cross-section, including Coulomb scattering as well as diffractive scattering (i.e. diffraction because the protons are not point particles, and have an internal structure (i.e. quarks)). Effectively, these are detectors for studying Regge theory. The goal is to search for elastic scattering effects beyond the Standard Model, such as hypothetical "colorless gluons", as well confirming ideas of pomeron exchange, and the possible existence of an odderon.
Odderons were potentially observed only in 2017 by the TOTEM experiment at the LHC. This observation was later confirmed in a joint analysis with the DØ experiment at the Tevatron.
The figure below shows a
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https://en.wikipedia.org/wiki/Mental%20nerve
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The mental nerve is a sensory nerve of the face. It is a branch of the posterior trunk of the inferior alveolar nerve, itself a branch of the mandibular nerve (CN V3), itself a branch of the trigeminal nerve (CN V). It provides sensation to the front of the chin and the lower lip, as well as the gums of the anterior mandibular (lower) teeth. It can be blocked with local anaesthesia for procedures on the chin, lower lip, and mucous membrane of the inner cheek. Problems with the nerve cause chin numbness.
Structure
The mental nerve is a branch of the posterior trunk of the inferior alveolar nerve. This is a branch of the mandibular nerve (CN V3), itself a branch of the trigeminal nerve (CN V). It emerges from the mental foramen in the mandible. It divides into three branches beneath the depressor anguli oris muscle. One branch descends to the skin of the chin. Two branches ascend to the skin and mucous membrane of the lower lip. These branches communicate freely with the facial nerve.
Function
The mental nerve provides sensation to the front of the chin and the lower lip. It also provides sensation to some of the gums of the anterior mandibular (lower) teeth.
Clinical significance
Anaesthesia
The mental nerve can be blocked with local anesthesia. This can be used in surgery of the chin, the lower lip, and the buccal mucosa from midline to the second premolar. In animals, it can be used in surgery of the lower lip, and lower teeth anterior to the site of administration. Local anesthetic is injected into the soft tissue surrounding the mental foramen, or more rarely into the mental foramen itself (although this can cause damage).
Chin numbness
Problems with the mental nerve can cause numbness over the chin. This can be caused by many different illnesses.
Reflexes
When the mental nerve is stimulated with electricity, muscles that close the jaw (particularly temporalis muscle and masseter muscle) are inhibited. This is a brainstem reflex.
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https://en.wikipedia.org/wiki/Superior%20laryngeal%20nerve
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The superior laryngeal nerve is a branch of the vagus nerve. It arises from the middle of the inferior ganglion of vagus nerve and additionally also receives a sympathetic branch from the superior cervical ganglion.
The superior laryngeal nerve produces of two branches: the internal laryngeal nerve (its sensory branch) which supplies sensory fibers to the laryngeal mucosa, and the external laryngeal nerve (its motor branch) which innervates the cricothyroid muscle.
Structure
Origin
The superior laryngeal nerve arises from the middle of the inferior ganglion of vagus nerve.
Course
The superior laryngeal nerve descends by the side of the pharynx deep to the internal carotid artery before dividing into two branches —the external laryngeal nerve and the internal laryngeal nerve.
Branches
External laryngeal nerve
The external laryngeal nerve is the smaller, external branch. It descends on the larynx, beneath the sternothyroid muscle, to supply the cricothyroid muscle. The external branch functions to tense the vocal cords by activating the cricothyroid muscle, increasing pitch. The external laryngeal nerve gives branches to pharyngeal plexus and the superior portion of the inferior pharyngeal constrictor, and communicates with the superior cardiac nerve behind the common carotid artery.
Internal laryngeal nerve
The internal laryngeal nerve is the internal branch. It descends to the thyrohyoid membrane, piercing it in company with the superior laryngeal artery, and is distributed to the mucous membrane of the larynx. Of these sensory branches, some are distributed to the epiglottis, the base of the tongue, and the epiglottic glands; others pass posteriorly, in the aryepiglottic fold, to supply the mucous membrane surrounding the entrance of the larynx, and the mucous lining of the larynx as far down as the vocal folds.
A filament descends beneath the mucous membrane on the inner surface of the thyroid cartilage and joins the recurrent laryngeal nerve. Above th
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https://en.wikipedia.org/wiki/CDC%20display%20code
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Display code is the six-bit character code used by many computer systems manufactured by Control Data Corporation, notably the CDC 6000 series in 1964, the 7600 in 1967 and the following Cyber series in 1971. The CDC 6000 series and their successors had 60 bit words. As such, typical usage packed 10 characters per word. It is a six-bit extension of the four-bit BCD encoding, and was referred to as BCDIC (BCD interchange code.)
There were several variations of display code, notably the 63-character character set, and the 64-character character set. There were also 'CDC graphic' and 'ASCII graphic' variants of both the 63- and 64-character sets. The choice between 63- or 64-character character set, and between CDC or ASCII graphic was site-selectable. Generally, early CDC customers started out with the 63-character character set, and CDC graphic print trains on their line printers. As time-sharing became prevalent, almost all sites used the ASCII variant - so that line printer output would match interactive usage. Later CDC customers were also more likely to use the 64-character character set.
A later variation, called 6/12 display code, was used in the Kronos and NOS timesharing systems in order to support full ASCII capabilities. In 6/12 mode, an escape character (the circumflex, octal 76) would indicate that the following letter was lower case. Thus, upper case and other characters were 6 bits in length, and lower case characters were 12 bits in length.
The PLATO system used a further variant of 6/12 display code. Noting that lower case letters were most common in typical PLATO usage, the roles were reversed. Lower case letters were the norm, and the escape character preceded upper case letters.
The typical text file format used a zero-byte terminator to signify the end of each record. The zero-byte terminator was indicated by, at least, the final twelve bits of a 60-bit word being set to zero. The terminator could actually be anywhere from 12- to
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https://en.wikipedia.org/wiki/Nasopalatine%20nerve
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The nasopalatine nerve (also long sphenopalatine nerve) is a nerve of the head. It is a sensory branch of the maxillary nerve (CN V2) that passes through the pterygopalatine ganglion (without synapsing) and then through the sphenopalatine foramen to enter the nasal cavity, and finally out of the nasal cavity through the incisive canal and then the incisive fossa to enter the hard palate. It provides sensory innervation to the posteroinferior part of the nasal septum, and gingiva just posterior to the upper incisor teeth.
The nasopalatine nerve is the largest of the medial posterior superior nasal nerves.
Structure
Course
It exits the pterygopalatine fossa through the sphenopalatine foramen to enter the nasal cavity. It passes across the roof of the nasal cavity below the orifice of the sphenoidal sinus to reach the posterior part of the nasal septum. It passes anteroinferiorly upon the nasal septum along a groove upon the vomer, running between the periosteum and mucous membrane of the lower part of the nasal septum. It then passes through the hard palate by descending through the incisive canal to reach the roof of the mouth.
Distribution
The nasopalatine nerve provides sensory innervation to the posteroinferior portion of the nasal septum, and the anterior-most portion of the hard palate (i.e. the gingiva/mucous membrane of the palate just posterior to the upper incisors).
Communications
The nasopalatine nerve communicates with the corresponding nerve of the opposite side and with the greater palatine nerve.
Clinical significance
The nasopalatine nerve may be anaesthetised in order to perform surgery on the hard palate or the soft palate.
History
The nasopalatine nerve was first identified by Domenico Cotugno.
Additional images
See also
Foramina of Scarpa
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https://en.wikipedia.org/wiki/Perineal%20nerve
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The perineal nerve is a nerve of the pelvis. It arises from the pudendal nerve in the pudendal canal. It gives superficial branches to the skin, and a deep branch to muscles. It supplies the skin and muscles of the perineum. Its latency is tested with electrodes.
Structure
The perineal nerve is a branch of the pudendal nerve. It lies below the internal pudendal artery. It accompanies the perineal artery. It passes through the pudendal canal for around 2 or 3 cm. Whilst still in the canal, it divides into superficial branches and a deep branch. The superficial branches of the perineal nerve become the posterior scrotal nerves in men, and the posterior labial nerves in women. The deep branch of the perineal nerve (also known as the "muscular" branch) travels to the muscles of the perineum. Both of these are superficial to the dorsal nerve of the penis or the dorsal nerve of the clitoris.
Function
The perineal nerve supplies the skin and muscles of the perineum. The superficial branches supply sensation to the perineum, and the scrotum in men or the labia majora in women. The deep branch supplies superficial transverse perineal muscle, the bulbospongiosus muscle, the ischiocavernosus muscle, the bulb of penis, levator ani, and the external anal sphincter.
Clinical significance
The latency of the perineal nerve can be measured with electrodes. It is used to test nerve function.
Additional images
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https://en.wikipedia.org/wiki/Zygomaticotemporal%20nerve
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The zygomaticotemporal nerve (zygomaticotemporal branch, temporal branch) is a cutaneous (sensory) nerve of the head. It is a branch of the zygomatic nerve (itself a branch of the maxillary nerve (CN V2)). It arises in the orbit and exits the orbit through the zygomaticotemporal foramen in the zygomatic bone to enter the temporal fossa. It is distributed to the skin of the side of the forehead. It also contains a parasympathetic secretomotor component for the lacrimal gland which it confers to the lacrimal nerve (which then delivers it to the gland).
Structure
Origin
The zygomaticotemporal nerve is a branch of the zygomatic nerve.
Course
It passes along the lateral wall of the orbit in a groove in the zygomatic bone.
It passes through the zygomaticotemporal foramen of the zygomatic bone to emerge (at the anterior portion of) the temporal fossa.
In the temporal fossa, it passes superior-ward between the two layers of the temporal fascia, between the temporal bone and temporalis muscle. It pierces the temporal fascia about 2 cm superior to the zygomatic arch.
As it pierces the deep layer of temporal fascia, it issues a small branch which runs between the two layers of the temporalis fascia to the lateral angle of the orbit.
Distribution
The nerve provides sensory innervation to a small area of skin over the temple superior to the zygomatic arch.
Communications
The zygomaticotemporal nerve communicates with the facial nerve (CN VII) (in most individuals), the lacrimal nerve (a branch of the ophthalmic nerve (CN V1)), and the auriculotemporal nerve (a branch of the mandibular nerve (CN V3)).
The zygomaticotemporal nerve confers a parasympathetic secretomotor communicating branch (containing post-ganglionic fibres for the lacrimal gland from the pterygopalatine ganglion) to the lacrimal nerve at the superior portion of the lateral wall of the orbit.
Variation
Sometimes, the zygomaticotemporal nerve replaces the lacrimal nerve and vice versa.
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https://en.wikipedia.org/wiki/Lower%20subscapular%20nerve
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The lower subscapular nerve, also known as the inferior subscapular nerve, is the third branch of the posterior cord of the brachial plexus. It innervates the inferior portion of the subscapularis muscle and the teres major muscle.
Structure
The lower subscapular nerve contains axons from the ventral rami of the C5 and C6 cervical spinal nerves. It is the third branch of the posterior cord of the brachial plexus. It gives branches to 2 muscles:
subscapularis muscle. It usually gives 4 branches to innervate the subscapularis, and can give up to 8 branches.
teres major muscle.
Function
The lower subscapular nerve innervates the subscapularis muscle and the teres major muscle. These muscles medially rotate and adduct the humerus.
Additional images
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https://en.wikipedia.org/wiki/Renal%20plexus
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The renal plexus is a complex network of nerves formed by filaments from the celiac ganglia and plexus, aorticorenal ganglia, lower thoracic splanchnic nerves and first lumbar splanchnic nerve and aortic plexus.
The nerves from these sources, fifteen or twenty in number, have a few ganglia developed upon them.
It enters the kidneys on arterial branches to supply the vessels, Renal glomerulus, and tubules with branches to the ureteric plexus. Some filaments are distributed to the spermatic plexus and, on the right side, to the inferior vena cava.
The ovarian plexus arises from the renal plexus, and is one of two sympathetic supplies distributed to the ovary and fundus of the uterus.
Additional images
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https://en.wikipedia.org/wiki/Desulfovibrio
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Desulfovibrio is a genus of Gram-negative sulfate-reducing bacteria. Desulfovibrio species are commonly found in aquatic environments with high levels of organic material, as well as in water-logged soils, and form major community members of extreme oligotrophic habitats such as deep granitic fractured rock aquifers.
High amounts of Desulfovibrio bacteria have been associated with inflammatory bowel disease, bacteremia infections and Parkinson's disease.
Some Desulfovibrio species have in recent years been shown to have bioremediation potential for toxic radionuclides such as uranium by a reductive bioaccumulation process, such as converting highly water-soluble U(VI) to relatively insoluble U(IV) precipitate, thus removing the toxic uranium from contaminated water.
Phylogeny
The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
Unassigned species:
"D. caledoniensis" Tardy-Jacquenod et al. 1996
"D. cavernae" Sass & Cypionka 2004
"D. diazotrophica" Sayavedra et al. 2021
"D. halohydrocarbonoclasticus" Zobell 1947
"D. hontreensis" Tarasov et al. 2015
"D. lacusfryxellense" Sattley & Madigan 2010
"D. multispirans" Czechowski et al. 1984
"D. oliviopondense" Qatabi Sr. 2007
"D. oryzae" Ouattara et al. 2000b
"D. rubentschikii" (Baars 1930) ZoBell 1948
"D. singaporenus" Sheng et al. 2007
See also
List of bacterial orders
List of bacteria genera
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https://en.wikipedia.org/wiki/Intercostobrachial%20nerve
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The intercostobrachial nerve is the name applied to the lateral cutaneous branch of the second intercostal nerve. It arises anterior to the long thoracic nerve. It provides sensory innervation to the skin of the axilla, and a variable region of the medial side of the upper arm.
Anatomy
The lateral cutaneous branch of the second intercostal nerve does not divide like other intercostal nerves into an anterior and a posterior branch.
Course
It pierces the intercostalis externus muscle and the serratus anterior muscle, crosses the axilla to the medial side of the arm, and joins with a filament from the medial brachial cutaneous nerve. It then pierces the fascia, and supplies the skin of the upper half of the medial and posterior part of the arm, communicating with the posterior brachial cutaneous branch of the radial nerve.
Relations
The size of the intercostobrachial nerve is in inverse relationship to that of the medial brachial cutaneous nerve.
Variation
An additional intercostobrachial nerve is frequently given off from the lateral cutaneous branch of the third intercostal nerves; it supplies filaments to the axilla and medial side of the arm.
Clinical significance
It is often the source of referred cardiac pain.
The intercostobrachial nerve is sometimes divided in axillary node clearance (ANC), such as that done for breast cancer surgery which requires the removal of the axillary nodes. Sensation to the cutaneous region supplied by the nerve is affected.
See also
Cutaneous innervation of the upper limbs
Additional images
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https://en.wikipedia.org/wiki/First%20quantization
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A first quantization of a physical system is a possibly semiclassical treatment of quantum mechanics, in which particles or physical objects are treated using quantum wave functions but the surrounding environment (for example a potential well or a bulk electromagnetic field or gravitational field) is treated classically.
However, this need not be the case. In particular, a fully quantum version of the theory can be created by interpreting the interacting fields and their associated potentials as operators of multiplication, provided the potential is written in the canonical coordinates that are compatible with the Euclidean coordinates of standard classical mechanics. First quantization is appropriate for studying a single quantum-mechanical system (not to be confused with a single particle system, since a single quantum wave function describes the state of a single quantum system, which may have arbitrarily many complicated constituent parts, and whose evolution is given by just one uncoupled Schrödinger equation) being controlled by laboratory apparatuses that are governed by classical mechanics, for example an old fashion voltmeter (one devoid of modern semiconductor devices, which rely on quantum theory—however though this is sufficient, it is not necessary), a simple thermometer, a magnetic field generator, and so on.
History
Published in 1901, Max Planck deduced the existence and value of the constant now bearing his name from considering only Wien's displacement law, statistical mechanics, and electromagnetic theory. Four years later in 1905, Albert Einstein went further to elucidate this constant and its deep connection to the stopping potential of photons emitted in the photoelectric effect. The energy in the photoelectric effect depended not only on the number of incident photons (the intensity of light) but also the frequency of light, a novel phenomena at the time, which would earn Einstein the 1921 Nobel Prize in Physics. It can then be concluded t
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https://en.wikipedia.org/wiki/CER-10
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CER model 10 was a vacuum tube, transistor and electronic relay based computer developed at IBK-Vinča and the Mihajlo Pupin Institute (Belgrade) in 1960. It was the first digital computer developed in SFR Yugoslavia, and in Southern Europe.
CER-10 was designed by Tihomir Aleksić and his associates (Rajko Tomović, Vukašin Masnikosa, Ahmed Mandžić, Dušan Hristović, Petar Vrbavac and Milojko Marić) and was developed over four years. The team included 10 engineers and 10 technicians, as well as many others. After initial prototype testing at Vinča and a redesign at the M. Pupin Institute, it was fully deployed at the Tanjug Agency building and worked there for the SKNE from 1961 and the Yugoslav government's SIV, from 1963 to 1967.
The first CER-10 system was located at the SKNE (Federal secretary of internal affairs) building in 1961, which would later belong to Tanjug. The M. Pupin Institute donated the computer's case and some parts of the CER-10 along with its documentation to the Museum of Science and Technology in Belgrade in March 2006, where the computer's CPU is now displayed.
Specifications
1750 vacuum tubes
1500 transistors
14000 Germanium diodes
Magnetic core primary memory: 4096 of 30-bit words
Secondary memory: punched tape
Capable of performing min. 1600 additions per second
Gallery
See also
CER Computers
Mihajlo Pupin Institute
History of computer hardware in the SFRY
List of vacuum tube computers
Rajko Tomović
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https://en.wikipedia.org/wiki/Load%20profile
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In electrical engineering, a load profile is a graph of the variation in the electrical load versus time. A load profile will vary according to customer type (typical examples include residential, commercial and industrial), temperature and holiday seasons. Power producers use this information to plan how much electricity they will need to make available at any given time. Teletraffic engineering uses a similar load curve.
Power generation
In a power system, a load curve or load profile is a chart illustrating the variation in demand/electrical load over a specific time. Generation companies use this information to plan how much power they will need to generate at any given time. A load duration curve is similar to a load curve. The information is the same but is presented in a different form. These curves are useful in the selection of generator units for supplying electricity.
Electricity distribution
In an electricity distribution grid, the load profile of electricity usage is important to the efficiency and reliability of power transmission. The power transformer or battery-to-grid are critical aspects of power distribution and sizing and modelling of batteries or transformers depends on the load profile. The factory specification of transformers for the optimization of load losses versus no-load losses is dependent directly on the characteristics of the load profile that the transformer is expected to be subjected to. This includes such characteristics as average load factor, diversity factor, utilization factor, and demand factor, which can all be calculated based on a given load profile.
On the power market so-called EFA blocks are used to specify the traded forward contract on the delivery of a certain amount of electrical energy at a certain time.
Retail energy markets
In retail energy markets, supplier obligations are settled on an hourly or subhourly basis. For most customers, consumption is measured on a monthly basis, based on meter reading s
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https://en.wikipedia.org/wiki/EGS%20%28program%29
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The EGS (Electron Gamma Shower) computer code system is a general purpose package for the Monte Carlo simulation of the coupled transport of electrons and photons in an arbitrary geometry for particles with energies from a few keV up to several hundreds of GeV. It originated at SLAC but National Research Council of Canada and KEK have been involved in its development since the early 80s.
Development of the original EGS code ended with version EGS4. Since then two groups have re-written the code with new physics:
EGSnrc, maintained by the Ionizing Radiation Standards Group, Measurement Science and Standards, National Research Council of Canada
EGS5, maintained by KEK, the Japanese particle physics research facility.
EGSnrc
EGSnrc is a general-purpose software toolkit that can be applied to build Monte Carlo simulations of coupled electron-photon transport, for particle energies ranging from 1 keV to 10 GeV. It is widely used internationally in a variety of radiation-related fields. The EGSnrc implementation improves the accuracy and precision of the charged particle transport mechanics and the atomic scattering cross-section data. The charged particle multiple scattering algorithm allows for large step sizes without sacrificing accuracy - a key feature of the toolkit that leads to fast simulation speeds. EGSnrc also includes a C++ class library called egs++ that can be used to model elaborate geometries and particle sources.
EGSnrc is open source and distributed on GitHub under the GNU Affero General Public License. Download EGSnrc for free, submit bug reports, and contribute pull requests on a group GitHub page. The documentation for EGSnrc is also available online.
EGSnrc is distributed with a wide range of applications that utilize the radiation transport physics to calculate specific quantities. These codes have been developed by numerous authors over the lifetime of EGSnrc to support the large user community. It is possible to calculate quantities such a
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https://en.wikipedia.org/wiki/Lateral%20pectoral%20nerve
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The lateral pectoral nerve (also known as the lateral anterior thoracic nerve) arises from the lateral cord of the brachial plexus, and through it from the C5-7.
It passes across the axillary artery and vein, pierces the clavipectoral (coracoclavicular) fascia, and enters the deep surface of the pectoralis major to innervate it.
Function
The lateral pectoral nerve provides motor innervation to the pectoralis major muscle.
Although this nerve is described as mostly motor, it also has been considered to carry proprioceptive and nociceptive fibers. It arises either from the lateral cord or directly from the anterior divisions of the upper and middle trunks of the brachial plexus. This is unlike the medial pectoral nerve, which derives from the medial cord (or directly from the anterior division of the lower trunk). It splits into four to seven branches that pierce the clavipectoral fascia to innervate the entire pectoralis major or its superior portion.
The medial and lateral pectoral nerves form a connection, around the axillary artery, called the ansa pectoralis. The lateral pectoral nerve has been described as double, while the medial pectoral nerve has been described as single.
Clinical significance
Postoperative Care
The lateral pectoral nerve is important in the pain response after breast augmentation and mastectomy, and especially in breast implant surgery, when the implant is inserted by the subpectoral route. The pectoral nerves can be anesthetized (blocked) intraoperatively by the surgeon under direct vision by three injections - one to block the medial pectoral nerve, the second to block the perforating branches of the medial pectoral nerve, and the third to block the lateral pectoral nerve. An ultrasound-guided pectoral nerve block can also be performed preventively before the operation by an anesthesiologist, experienced in regional anesthesia. It is safe and relies on ultrasound imaging to localize the pectoralis major and minor muscles, the presu
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https://en.wikipedia.org/wiki/Mihajlo%20Pupin%20Institute
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Mihajlo Pupin Institute () is an institute based in Belgrade, Serbia. It is named after Mihajlo Idvorski Pupin and is part of the University of Belgrade.
It is notable for manufacturing numerous computer systems used in SFR Yugoslavia - especially early CER and later TIM line of computers.
Departments
The institute is well known in wide range of fields. In the science community, it is known for early work in humanoid robotics.
The institute and companies owned by it compete in fields such as:
System integration and networking,
Information systems for government and industry, Internet/Intranet IS
E-commerce, e-government applications
Decision support systems, expert systems, intelligent Internet applications,
Power systems control, supervision and optimization
Process control and supervision,
Traffic control, GPS
Telecommunications
Digital signal processing
Simulators, training aids, specialised H/S systems
Image processing
Real-time systems (large scale and embedded)
Turn-key engineering solutions
Robotics
Subsidiaries
IMP-Automatika d.o.o. Belgrade
IMP-Računarski sistemi d.o.o. Belgrade
IMP-Telekomunikacije d.o.o. Belgrade
Idvorski laboratorije d.o.o. Belgrade
IMP-Piezotehnologija d.o.o. Belgrade
IMP-Poslovne usluge d.o.o. Belgrade
IMP-Naučnotehnološki park d.o.o. Belgrade
See also
CER Computers
HRS-100 computer
TIM-100 and TIM-011
Michael I. Pupin - Serbian scientist after whom this institute is named.
History of computer hardware in the SFRY
Rajko Tomović
Miomir Vukobratović
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https://en.wikipedia.org/wiki/Logarithmic%20mean
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In mathematics, the logarithmic mean is a function of two non-negative numbers which is equal to their difference divided by the logarithm of their quotient.
This calculation is applicable in engineering problems involving heat and mass transfer.
Definition
The logarithmic mean is defined as:
for the positive numbers .
Inequalities
The logarithmic mean of two numbers is smaller than the arithmetic mean and the generalized mean with exponent one-third but larger than the geometric mean, unless the numbers are the same, in which case all three means are equal to the numbers.
Toyesh Prakash Sharma generalizes the arithmetic logarithmic geometric mean inequality for any belongs to the whole number as
Now, for :
This is the arithmetic logarithmic geometric mean inequality. similarly, one can also obtain results by putting different values of as below
For :
for the proof go through the bibliography.
Derivation
Mean value theorem of differential calculus
From the mean value theorem, there exists a value in the interval between and where the derivative equals the slope of the secant line:
The logarithmic mean is obtained as the value of by substituting for and similarly for its corresponding derivative:
and solving for :
Integration
The logarithmic mean can also be interpreted as the area under an exponential curve.
The area interpretation allows the easy derivation of some basic properties of the logarithmic mean. Since the exponential function is monotonic, the integral over an interval of length 1 is bounded by and . The homogeneity of the integral operator is transferred to the mean operator, that is .
Two other useful integral representations areand
Generalization
Mean value theorem of differential calculus
One can generalize the mean to variables by considering the mean value theorem for divided differences for the -th derivative of the logarithm.
We obtain
where denotes a divided difference of the logarithm.
For this leads
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https://en.wikipedia.org/wiki/Barton%27s%20pendulums
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First demonstrated by Prof Edwin Henry Barton FRS FRSE (1858–1925), Professor of Physics at University College, Nottingham, who had a particular interest in the movement and behavior of spherical bodies, the Barton's pendulums experiment demonstrates the physical phenomenon of resonance and the response of pendulums to vibration at, below and above their resonant frequencies. In its simplest construction, approximately 10 different pendulums are hung from one common string. This system vibrates at the resonance frequency of a driver pendulum, causing the target pendulum to swing with the maximum amplitude. The other pendulums to the side do not move as well, thus demonstrating how torquing a pendulum at its resonance frequency is most efficient.
The driver may be a very heavy pendulum also attached to this common string; the driver is set to swing and move the whole system.
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https://en.wikipedia.org/wiki/Tagged%20Command%20Queuing
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Tagged Command Queuing (TCQ) is a technology built into certain ATA and SCSI hard drives. It allows the operating system to send multiple read and write requests to a hard drive. ATA TCQ is not identical in function to the more efficient Native Command Queuing (NCQ) used by SATA drives. SCSI TCQ does not suffer from the same limitations as ATA TCQ.
Without TCQ, an operating system was limited to sending one request at a time. To boost performance, the OS had to determine the order of the requests based on its own possibly incorrect perspective of the hard drive activity (otherwise known as I/O scheduling). With TCQ, the drive can make its own decisions about how to order the requests (and in turn relieve the operating system from having to do so). Thus TCQ can improve the overall performance of a hard drive if it is implemented correctly.
Overview
For increased efficiency the sectors should be serviced in order of proximity to the current head position, not the order received. The queue is constantly receiving new requests, fulfilling and removing existing requests, and re-ordering the queue according to the current pending read/write requests and the changing position of the head. The exact reordering algorithm may depend upon the controller and the drive itself, but the host computer simply makes requests as needed, leaving the controller to handle the details.
This queuing mechanism is sometimes referred to as "elevator seeking", as the image of a modern elevator in a building servicing multiple calls and processing them to minimise travel illustrates the idea well.
If the buttons for floors 5, 2, and 4 are pressed in that order with the elevator starting on floor 1, an old elevator would go to the floors in the order requested. A modern elevator processes the requests to stop at floors in the logical order 2, 4, and 5, without unnecessary travel. Non-queueing disk drives service the requests in the order received, like an old elevator; queueing drives serv
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https://en.wikipedia.org/wiki/VeryCD
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VeryCD is a Chinese website that shares files via eD2k links. The website was begun in September 2003 by Huang Yimeng (). In June 2005, Shanghai Source Networking Technology Co., Ltd (, or VeryCD company) was established. It is a for-profit organization headquartered in Shanghai, China. Today, VeryCD is one of the most popular file-sharing (via ed2k links) websites in China.
Aims
According to VeryCD company, VeryCD.com "aims to be the biggest and the most user-friendly P2P seed database website in the world. […] Its declaration against corruption from capitalized operation kept the website organized and free of advertisement abuse." But some people thought that it was contradictory, since VeryCD was already a commercial company which had a lot of advertisement on the website. The creator of the website and leader of the VeryCD company, Huang Yimeng was also listed in a "list of Chinese multimillionaires born in 1980s" by some Chinese media.
Software
Two eDonkey network clients, eMule VeryCD Mod and easyMule, are developed by VeryCD company.
eMule VeryCD Mod
eMule VeryCD Mod developed since 2003 is based on eMule and open-sourced. It has a built-in browser to access the Web.
Due to the censorship in China, eMule VeryCD Mod has a search word filter to prevent users from searching some political or pornographic words.
easyMule
easyMule developed since 2007 is now the company's primary client. It removes the category, message, IRC, custom skin and some other features from eMule, adds BHO (Browser Helper Object) plug-in to users' IE browser. The browser built in easyMule can only access VeryCD.com site.
easyMule's users can't search via eDonkey servers or Kad network, it is only allowed to search from the links indexed by VeryCD.com.
easyMule version 1 is eMule-based and open-sourced. Since v2.0, easyMule has closed its source. VeryCD company's developer claimed that easyMule 2.0 is written from scratch by them. On 1 July 2009, an aMule developer wrote a topic on
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https://en.wikipedia.org/wiki/Emergent%20gravity
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Emergent gravity may refer to
Induced gravity, a theory proposed by Andrei Sakharov in 1967,
Entropic gravity, a theory proposed by Erik Verlinde in 2009.
Theories of gravity
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https://en.wikipedia.org/wiki/NEC%20SX-8
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The SX-8 is a supercomputer built by NEC Corporation. The SX-8 Series implements an eight-way SMP system in a compact node module and uses an enhanced version of the single chip vector processor that was introduced with the SX-6. The NEC SX-8 processors run at 2 GHz for vectors and 1 GHz for scalar operations. The SX-8 CPU operates at 16 GFLOPS and can address up to 128 GB of memory. Up to 8 CPUs may be used in a single node, and a complete system may have up to 512 nodes. The SX-8 series ranges from the single-CPU SX-8b system to the SX-8/4096M512, with 512 nodes, 4,096 CPUs, and a peak performance of 65 TFLOPS. There is up to 512 GB/s bandwidth per node (64 GB/s per processor). The SX-8 runs SUPER-UX, a Unix-like operating system developed by NEC.
The first production SX-8 was installed at the UK Met Office in early 2005. In October 2006, an upgraded SX-8 was announced, the SX-8R. The NEC SX-8R processors run at 2.2 GHz for vectors and 1.1 GHz for scalar operations. The SX-8R can process double the number of vector operations per clock compared to the SX-8. The SX-8R CPU has a peak vector performance 35.2 GFLOPS (10% frequency increase and double the number of vector operations) and can address up to 256 GB of memory in a single node (up from 128 GB).
The French national meteorological service, Météo-France, rents a SX-8R for 3.7 million euros a year.
NEC published product highlights
16 GFLOPS peak vector performance, with eight operations per clock running at 2 GHz or 0.5 ns (1 GHz for scalar)
88 million transistors per CPU, 1.0 V, 8,210 pins (1,923 signal pins)
Up to 8 CPUs per node, manufactured in 90 nm Cu technology, 9 copper layers, bare chip packaging
Up to 16 GB of memory per CPU, 128 GB in a single node
Up to 512 GB/s bandwidth per node, 64 GB/s per CPU
IXS Super-Switch between nodes, up to 512 nodes supported, 32 GB/s per node (16 GB/s for each direction)
Air cooled
Runs SUPER-UX, System V port, 4.3 BSD with enhancements for multinode systems;
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https://en.wikipedia.org/wiki/Tautology%20%28logic%29
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In mathematical logic, a tautology (from ) is a formula or assertion that is true in every possible interpretation. An example is "x=y or x≠y". Similarly, "either the ball is green, or the ball is not green" is always true, regardless of the colour of the ball.
The philosopher Ludwig Wittgenstein first applied the term to redundancies of propositional logic in 1921, borrowing from rhetoric, where a tautology is a repetitive statement. In logic, a formula is satisfiable if it is true under at least one interpretation, and thus a tautology is a formula whose negation is unsatisfiable. In other words, it cannot be false. It cannot be untrue.
Unsatisfiable statements, both through negation and affirmation, are known formally as contradictions. A formula that is neither a tautology nor a contradiction is said to be logically contingent.
Such a formula can be made either true or false based on the values assigned to its propositional variables. The double turnstile notation is used to indicate that S is a tautology. Tautology is sometimes symbolized by "Vpq", and contradiction by "Opq". The tee symbol is sometimes used to denote an arbitrary tautology, with the dual symbol (falsum) representing an arbitrary contradiction; in any symbolism, a tautology may be substituted for the truth value "true", as symbolized, for instance, by "1".
Tautologies are a key concept in propositional logic, where a tautology is defined as a propositional formula that is true under any possible Boolean valuation of its propositional variables. A key property of tautologies in propositional logic is that an effective method exists for testing whether a given formula is always satisfied (equiv., whether its negation is unsatisfiable).
The definition of tautology can be extended to sentences in predicate logic, which may contain quantifiers—a feature absent from sentences of propositional logic.
Indeed, in propositional logic, there is no distinction between a tautology and a logically v
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https://en.wikipedia.org/wiki/Gavin%20de%20Beer
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Sir Gavin Rylands de Beer (1 November 1899 – 21 June 1972) was a British evolutionary embryologist, known for his work on heterochrony as recorded in his 1930 book Embryos and Ancestors. He was director of the Natural History Museum, London, president of the Linnean Society of London, and a winner of the Royal Society's Darwin Medal for his studies on evolution.
Biography
Born on 1 November 1899 in Malden, Surrey (now part of London), de Beer spent most of his childhood in France, where he was educated at the Parisian École Pascal. During this time, he also visited Switzerland, a country with which he remained fascinated for the rest of his life. His education continued at Harrow and Magdalen College, Oxford, where he graduated with a degree in zoology in 1921, after a pause to serve in the First World War in the Grenadier Guards and the Army Education Corps. In 1923 he was made a fellow of Merton College, Oxford, and began to teach at the university's zoology department. In 1938, he was made reader in embryology at University College, London.
During the Second World War, he again served with the Grenadier Guards reaching the rank of temporary lieutenant colonel. He worked in intelligence, propaganda and psychological warfare. In 1940, he was elected as a Fellow of the Royal Society.
In 1945, de Beer became professor of zoology and was, from 1946 to 1949, president of the Linnean Society. Then he was director of the British Museum (Natural History) (now the Natural History Museum), from 1950 until his retirement in 1960. He was knighted in 1954, and awarded the Darwin Medal of the Royal Society in 1957.
In 1958, he delivered the British Academy's Master-Mind Lecture, on Charles Darwin. In 1961 he gave the Royal Society of London's Wilkins Lecture.
After his retirement, de Beer moved to Switzerland and worked on several publications on Charles Darwin, including first publication of Darwin's manuscripts including his private notebooks, opening them to scholars
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https://en.wikipedia.org/wiki/Jordan%20matrix
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In the mathematical discipline of matrix theory, a Jordan matrix, named after Camille Jordan, is a block diagonal matrix over a ring (whose identities are the zero 0 and one 1), where each block along the diagonal, called a Jordan block, has the following form:
Definition
Every Jordan block is specified by its dimension n and its eigenvalue , and is denoted as . It is an matrix of zeroes everywhere except for the diagonal, which is filled with and for the superdiagonal, which is composed of ones.
Any block diagonal matrix whose blocks are Jordan blocks is called a Jordan matrix. This square matrix, consisting of diagonal blocks, can be compactly indicated as or , where the i-th Jordan block is .
For example, the matrix
is a Jordan matrix with a block with eigenvalue , two blocks with eigenvalue the imaginary unit , and a block with eigenvalue 7. Its Jordan-block structure is written as either or .
Linear algebra
Any square matrix whose elements are in an algebraically closed field is similar to a Jordan matrix , also in , which is unique up to a permutation of its diagonal blocks themselves. is called the Jordan normal form of and corresponds to a generalization of the diagonalization procedure. A diagonalizable matrix is similar, in fact, to a special case of Jordan matrix: the matrix whose blocks are all .
More generally, given a Jordan matrix , that is, whose th diagonal block, , is the Jordan block and whose diagonal elements may not all be distinct, the geometric multiplicity of for the matrix , indicated as , corresponds to the number of Jordan blocks whose eigenvalue is . Whereas the index of an eigenvalue for , indicated as , is defined as the dimension of the largest Jordan block associated to that eigenvalue.
The same goes for all the matrices similar to , so can be defined accordingly with respect to the Jordan normal form of for any of its eigenvalues . In this case one can check that the index of for is equal to its
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https://en.wikipedia.org/wiki/LR-attributed%20grammar
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LR-attributed grammars are a special type of attribute grammars. They allow the attributes to be evaluated on LR parsing. As a result, attribute evaluation in LR-attributed grammars can be incorporated conveniently in bottom-up parsing. zyacc is based on LR-attributed grammars. They are a subset of the L-attributed grammars, where the attributes can be evaluated in one left-to-right traversal of the abstract syntax tree. They are a superset of the S-attributed grammars, which allow only synthesized attributes. In yacc, a common hack is to use global variables to simulate some kind of inherited attributes and thus LR-attribution.
External links
http://www.cs.binghamton.edu/~zdu/zyacc/doc/zyacc_4.html
Reinhard Wilhelm: LL- and LR-Attributed Grammars. Programmiersprachen und Programmentwicklung, 7. Fachtagung, veranstaltet vom Fachausschuß 2 der GI (1982), 151–164, Informatik-Fachberichte volume 53.
J. van Katwijk: A preprocessor for YACC or A poor man's approach to parsing attributed grammars. Sigplan Notices 18:10 (1983), 12–15.
Formal languages
Compiler construction
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https://en.wikipedia.org/wiki/ECLR-attributed%20grammar
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ECLR-attributed grammars are a special type of attribute grammars.
They are a variant of LR-attributed grammars where an equivalence relation on inherited attributes is used to optimize attribute evaluation. EC stands for equivalence class. Rie is based on ECLR-attributed grammars.
External links
http://www.is.titech.ac.jp/~sassa/lab/rie-e.html
M. Sassa, H. Ishizuka and I. Nakata: ECLR-attributed grammars: a practical class of LR-attributed grammars. Inf. Process. Lett. 24 (1987), 31–41.
M. Sassa, H. Ishizuka and I. Nakata: Rie, a Compiler Generator Based on a One-pass-type Attribute Grammar. Software—practice and experience 25:3 (March 1995), 229–250.
Formal languages
Compiler construction
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https://en.wikipedia.org/wiki/Trimming%20%28computer%20programming%29
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In computer programming, trimming (trim) or stripping (strip) is a string manipulation in which leading and trailing whitespace is removed from a string.
For example, the string (enclosed by apostrophes)
' this is a test '
would be changed, after trimming, to
'this is a test'
Variants
Left or right trimming
The most popular variants of the trim function strip only the beginning or end of the string. Typically named ltrim and rtrim respectively, or in the case of Python: lstrip and rstrip. C# uses TrimStart and TrimEnd, and Common Lisp string-left-trim and string-right-trim. Pascal and Java do not have these variants built-in, although Object Pascal (Delphi) has TrimLeft and TrimRight functions.
Whitespace character list parameterization
Many trim functions have an optional parameter to specify a list of characters to trim, instead of the default whitespace characters. For example, PHP and Python allow this optional parameter, while Pascal and Java do not. With Common Lisp's string-trim function, the parameter (called character-bag) is required. The C++ Boost library defines space characters according to locale, as well as offering variants with a predicate parameter (a functor) to select which characters are trimmed.
Special empty string return value
An uncommon variant of trim returns a special result if no characters remain after the trim operation. For example, Apache Jakarta's StringUtils has a function called stripToNull which returns null in place of an empty string.
Space normalization
Space normalization is a related string manipulation where in addition to removing surrounding whitespace, any sequence of whitespace characters within the string is replaced with a single space. Space normalization is performed by the function named Trim() in spreadsheet applications (including Excel, Calc, Gnumeric, and Google Docs), and by the normalize-space() function in XSLT and XPath,
In-place trimming
While most algorithms return a new (trimmed) string,
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https://en.wikipedia.org/wiki/Topological%20quantum%20computer
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A topological quantum computer is a theoretical quantum computer proposed by Russian-American physicist Alexei Kitaev in 1997. It employs quasiparticles in two-dimensional systems, called anyons, whose world lines pass around one another to form braids in a three-dimensional spacetime (i.e., one temporal plus two spatial dimensions). These braids form the logic gates that make up the computer. The advantage of a quantum computer based on quantum braids over using trapped quantum particles is that the former is much more stable. Small, cumulative perturbations can cause quantum states to decohere and introduce errors in the computation, but such small perturbations do not change the braids' topological properties. This is like the effort required to cut a string and reattach the ends to form a different braid, as opposed to a ball (representing an ordinary quantum particle in four-dimensional spacetime) bumping into a wall.
While the elements of a topological quantum computer originate in a purely mathematical realm, experiments in fractional quantum Hall systems indicate these elements may be created in the real world using semiconductors made of gallium arsenide at a temperature of near absolute zero and subjected to strong magnetic fields.
Introduction
Anyons are quasiparticles in a two-dimensional space. Anyons are neither fermions nor bosons, but like fermions, they cannot occupy the same state. Thus, the world lines of two anyons cannot intersect or merge, which allows their paths to form stable braids in space-time. Anyons can form from excitations in a cold, two-dimensional electron gas in a very strong magnetic field, and carry fractional units of magnetic flux. This phenomenon is called the fractional quantum Hall effect. In typical laboratory systems, the electron gas occupies a thin semiconducting layer sandwiched between layers of aluminium gallium arsenide.
When anyons are braided, the transformation of the quantum state of the system depends only o
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https://en.wikipedia.org/wiki/Reproductive%20value%20%28population%20genetics%29
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Reproductive value is a concept in demography and population genetics that represents the discounted number of future female children that will be born to a female of a specific age. Ronald Fisher first defined reproductive value in his 1930 book The Genetical Theory of Natural Selection where he proposed that future offspring be discounted at the rate of growth of the population; this implies that sexually reproductive value measures the contribution of an individual of a given age to the future growth of the population.
Definition
Consider a species with a life history table with survival and reproductive parameters given by and , where
= probability of surviving from age 0 to age
and
= average number of offspring produced by an individual of age
In a population with a discrete set of age classes, Fisher's reproductive value is calculated as
where is the long-term population growth rate given by the dominant eigenvalue of the Leslie matrix. When age classes are continuous,
where is the intrinsic rate of increase or Malthusian growth rate.
See also
Population dynamics
Euler–Lotka equation
Leslie matrix
Senescence
Notes
Fisher, R. A. 1930. The Genetical Theory of Natural Selection. Oxford University Press, Oxford.
Keyfitz, N. and Caswell, H. 2005. Applied Mathematical Demography. Springer, New York. 3rd edition. doi:10.1007/b139042
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https://en.wikipedia.org/wiki/Old%20man%27s%20car
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An old man's car (or old person's car or old folk's car) is stereotype of a car that appeals to older buyers rather than to younger ones. It is widely held in the United States automobile industry that such cars are difficult to sell. Several automobile manufacturers have taken steps to shake the perception that their cars are intended for an older generation because it tarnishes the brand's image in the eyes of younger buyers.
Market focus
Two automobile company executives are associated with the adage that "You can sell a young man's car to an old man, but you cannot sell an old man's car to a young man." Lynn Townsend, who became president of Chrysler in 1961, and Semon Knudsen who became General Manager of Pontiac in July 1956. Knudsen espoused this philosophy during the changes that he made to Pontiac from 1957 to 1959, which began with the release of the Bonneville, intended to be a high profile announcement to the U.S. public that Pontiac was "no longer an old man's car company". Townsend had two teenage sons, who, according to Hoover (the engineering coordinator for the engineering division for the race programme in 1961), when Townsend took on the position of president "made it known to dad straightaway that this stuff was nowhere. He was highly sensitive to the fact that the product line was nowhere out there with the young people.". Townsend used this rationale in his directive to change the image of the product line in October 1961.
Advertising
Ford employed this adage in its advertising for the Ford Focus in the United States. One advertisement showed a group of youths climbing out of the rear of the car after having pulled into a parking space too narrow for them to open the side doors. Another showed a similar group of youths nervously holding coffee cups as the car passed over a series of railway tracks. Mueller observes that Ford "could just as easily have demonstrated the ease of entry or exit for a cane user [...] or a number of other features e
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https://en.wikipedia.org/wiki/European%20Data%20Format
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European Data Format (EDF) is a standard file format designed for exchange and storage of medical time series. Being an open and non-proprietary format, EDF(+) is commonly used to archive, exchange and analyse data from commercial devices in a format that is independent of the acquisition system. In this way, the data can be retrieved and analyzed by independent software. EDF(+) software (browsers, checkers, ...) and example files are freely available.
EDF was published in 1992 and stores multichannel data, allowing different sample rates for each signal. Internally it includes a header and one or more data records. The header contains some general information (patient identification, start time...) and technical specs of each signal (calibration, sampling rate, filtering, ...), coded as ASCII characters. The data records contain samples as little-endian 16-bit integers. EDF is a popular format for polysomnography (PSG) recordings.
EDF+ was published in 2003 and is largely compatible to EDF: all existing EDF viewers also show EDF+ signals. But EDF+ files also allow coding discontinuous recordings as well as annotations, stimuli and events in UTF-8 format. EDF+ has applications in PSG, electroencephalography (EEG), electrocardiography (ECG), electromyography (EMG), and Sleep scoring. EDF+ can also be used for nerve conduction studies, evoked potentials and other data acquisition studies.
Other "EDF" formats
The file extension "edf" may also stand for the ESRF data format, defined by the European Synchrotron Radiation Facility and frequently used for small-angle scattering data.
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https://en.wikipedia.org/wiki/Non-Euclidean%20crystallographic%20group
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In mathematics, a non-Euclidean crystallographic group, NEC group or N.E.C. group is a discrete group of isometries of the hyperbolic plane. These symmetry groups correspond to the wallpaper groups in euclidean geometry. A NEC group which contains only orientation-preserving elements is called a Fuchsian group, and any non-Fuchsian NEC group has an index 2 Fuchsian subgroup of orientation-preserving elements.
The hyperbolic triangle groups are notable NEC groups. Others are listed in Orbifold notation.
See also
Non-Euclidean geometry
Isometry group
Fuchsian group
Uniform tilings in hyperbolic plane
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