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https://en.wikipedia.org/wiki/Mobile%20media
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Mobile media has been defined as: "as a personal, interactive, internet-enabled and user-controlled portable platform that provides for the exchange of and sharing of personal and non-personal information among users who are inter-connected." The notion of making media mobile can be traced back to the “first time someone thought to write on a tablet that could be lifted and hauled – rather than on a cave wall, a cliff face, a monument that usually was stuck in place, more or less forever”. In his book Cellphone, Paul Levinson refers to mobile media as “the media-in-motion business.” Since their incarnation, mobile phones as a means of communication have been a focus of great fascination as well as debate. In the book, Studying Mobile Media: Cultural Technologies, Mobile Communication, and the iPhone, Gerard Goggin notes how the ability of portable voice communication to provide ceaseless contact complicates the relationship between the public and private spheres of society. Lee Humphreys' explains in her book that now, "more people in the world today have a mobile phone than have an Internet connection".
The development of the portable telephone can be traced back to its use by the military in the late nineteenth-century. By the 1930s, police cars in several major U.S. cities were equipped with one-way mobile radios. In 1931, the Galvin Manufacturing Corporation designed a mass market two-way radio. This radio was named Motorola, which also became the new name for the company in 1947. In 1943, Motorola developed the first portable radiotelephone, the Walkie-Talkie, for use by the American forces during World War II. After the war, two-way radio technology was developed for civilian use. In 1946, AT&T and Southwestern Bell made available the first commercial mobile radiotelephone. This service allowed calls to be made from a fixed phone to a mobile one.
"Many scholars have noted and praised the mobility of reading brought about the emergence of the book and the adv
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https://en.wikipedia.org/wiki/Root%20cellar
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A root cellar (American English), fruit cellar (Mid-Western American English) or earth cellar (British English) is a structure, usually underground or partially underground, used for storage of vegetables, fruits, nuts, or other foods. Its name reflects the traditional focus on root crops stored in an underground cellar, which is still often true; but the scope is wider, as a wide variety of foods can be stored for weeks to months, depending on the crop and conditions, and the structure may not always be underground.
Root cellaring has been vitally important in various eras and places for winter food supply. Although present-day food distribution systems and refrigeration have rendered root cellars unnecessary for many people, they remain important for those who value self-sufficiency, whether by economic necessity or by choice and for personal satisfaction. Thus, they are popular among diverse audiences, including gardeners, organic farmers, DIY fans, homesteaders, anyone seeking some emergency preparedness (most extensively, preppers), subsistence farmers, and enthusiasts of local food, slow food, heirloom plants, and traditional culture.
Function
Root cellars are for keeping food supplies at controlled temperatures and steady humidity. Many crops keep longest just above freezing () and at high humidity (90–95%), but the optimal temperature and humidity ranges vary by crop, and various crops keep well at temperatures further above near-freezing but below room temperature, which is usually . A few crops keep better in low humidity. Root cellars keep food from freezing during the winter and keep food cool during the summer to prevent the spoiling and rotting of the roots, for example, potatoes, onions, garlic, carrots, parsnips, etc.. Typically, a variety of vegetables is placed in the root cellar in the autumn after harvesting. A secondary use for the root cellar is as a place to store wine, beer, or other homemade alcoholic beverages.
Vegetables stored in the
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https://en.wikipedia.org/wiki/Abstract%20algebraic%20logic
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In mathematical logic, abstract algebraic logic is the study of the algebraization of deductive systems
arising as an abstraction of the well-known Lindenbaum–Tarski algebra, and how the resulting algebras are related to logical systems.
History
The archetypal association of this kind, one fundamental to the historical origins of algebraic logic and lying at the heart of all subsequently developed subtheories, is the association between the class of Boolean algebras and classical propositional calculus. This association was discovered by George Boole in the 1850s, and then further developed and refined by others, especially C. S. Peirce and Ernst Schröder, from the 1870s to the 1890s. This work culminated in Lindenbaum–Tarski algebras, devised by Alfred Tarski and his student Adolf Lindenbaum in the 1930s. Later, Tarski and his American students (whose ranks include Don Pigozzi) went on to discover cylindric algebra, whose representable instances algebraize all of classical first-order logic, and revived relation algebra, whose models include all well-known axiomatic set theories.
Classical algebraic logic, which comprises all work in algebraic logic until about 1960, studied the properties of specific classes of algebras used to "algebraize" specific logical systems of particular interest to specific logical investigations. Generally, the algebra associated with a logical system was found to be a type of lattice, possibly enriched with one or more unary operations other than lattice complementation.
Abstract algebraic logic is a modern subarea of algebraic logic that emerged in Poland during the 1950s and 60s with the work of Helena Rasiowa, Roman Sikorski, Jerzy Łoś, and Roman Suszko (to name but a few). It reached maturity in the 1980s with the seminal publications of the Polish logician Janusz Czelakowski, the Dutch logician Wim Blok and the American logician Don Pigozzi. The focus of abstract algebraic logic shifted from the study of specific classes of a
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https://en.wikipedia.org/wiki/Genevestigator
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Genevestigator is an application consisting of a gene expression database and tools to analyse the data. It exists in two versions, biomedical and plant, depending on the species of the underlying microarray and RNAseq as well as single-cell RNA-sequencing data. It was started in January 2004 by scientists from ETH Zurich and is currently developed and commercialized by Nebion AG.
Researchers and scientists from academia and industry use it to identify, characterize and validate novel drug targets and biomarkers, identify appropriate research models and in general to understand how gene expression changes with different treatments.
Gene expression database
The Genevestigator database comprises transciptomic data from numerous public repositories including GEO, Array Express and renowned cancer research projects as TCGA. Depending on the license agreement, it may also contain data from private gene expression studies. All data are manually curated, quality-controlled and enriched for sample and experiment descriptions derived from corresponding scientific publications.
The number of species from where the samples are derived is constantly increasing. Currently, the biomedical version contains data from human, mouse, and rat used in biomedical research. Gene expression studies are from various research areas including oncology, immunology, neurology, dermatology and cardiovascular diseases. Samples comprise tissue biopsies and cell lines.
The plant version (no longer available) contained both, widely used model species such as arabidopsis and medicago as well as major crop species such as maize, rice, wheat and soybean. After the acquisition of Nebion AG by Immunai Inc. in July 2021, plant data began to be phased out as the biotech company prioritized their focus on biopharma data. As of 2023, the plant data is being maintained on a separate server for remaining users with a license to the plant version of Genevestigator.
Gene expression tools
More than 60,000 s
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https://en.wikipedia.org/wiki/Inferior%20cerebral%20veins
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The inferior cerebral veins are veins that drain the undersurface of the cerebral hemispheres and empty into the cavernous and transverse sinuses.
Those on the orbital surface of the frontal lobe join the superior cerebral veins, and through these open into the superior sagittal sinus.
Those of the temporal lobe anastomose with the middle cerebral and basal veins, and join the cavernous, sphenoparietal, and superior petrosal sinuses.
Image
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https://en.wikipedia.org/wiki/Squamous%20part%20of%20temporal%20bone
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The squamous part of temporal bone, or temporal squama, forms the front and upper part of the temporal bone, and is scale-like, thin, and translucent.
Surfaces
Its outer surface is smooth and convex; it affords attachment to the temporal muscle, and forms part of the temporal fossa; on its hinder part is a vertical groove for the middle temporal artery. A curved line, the temporal line, or supramastoid crest, runs backward and upward across its posterior part; it serves for the attachment of the temporal fascia, and limits the origin of the temporalis muscle. The boundary between the squamous part and the mastoid portion of the bone, as indicated by traces of the original suture, lies about 1 cm. below this line.
Projecting from the lower part of the squamous part is a long, arched process, the zygomatic process. This process is at first directed lateralward, its two surfaces looking upward and downward; it then appears as if twisted inward upon itself, and runs forward, its surfaces now looking medialward and lateralward. The superior border is long, thin, and sharp, and serves for the attachment of the temporal fascia; the inferior, short, thick, and arched, has attached to it some fibers of the masseter. The lateral surface is convex and subcutaneous; the medial is concave, and affords attachment to the masseter. The anterior end is deeply serrated and articulates with the zygomatic bone. The posterior end is connected to the squamous part by two roots, the anterior and posterior roots. The posterior root, a prolongation of the upper border, is strongly marked; it runs backward above the external auditory meatus, and is continuous with the temporal line. The anterior root, continuous with the lower border, is short but broad and strong; it is directed medialward and ends in a rounded eminence, the articular tubercle (eminentia articularis).
This tubercle forms the front boundary of the mandibular fossa, and in the fresh state is covered with cartilage. In fro
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https://en.wikipedia.org/wiki/Mastoid%20part%20of%20the%20temporal%20bone
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The mastoid part of the temporal bone is the posterior (back) part of the temporal bone, one of the bones of the skull. Its rough surface gives attachment to various muscles (via tendons) and it has openings for blood vessels. From its borders, the mastoid part articulates with two other bones.
Etymology
The word "mastoid" is derived from the Greek word for "breast", a reference to the shape of this bone.
Surfaces
Outer surface
Its outer surface is rough and gives attachment to the occipitalis and posterior auricular muscles. It is perforated by numerous foramina (holes); for example, the mastoid foramen is situated near the posterior border and transmits a vein to the transverse sinus and a small branch of the occipital artery to the dura mater. The position and size of this foramen are very variable; it is not always present; sometimes it is situated in the occipital bone, or in the suture between the temporal and the occipital.
Mastoid process
The mastoid process is located posterior and inferior to the ear canal, lateral to the styloid process, and appears as a conical or pyramidal projection. It forms a bony prominence behind and below the ear. It has variable size and form (e.g. it is larger in the male than in the female). It is also filled with sinuses, or mastoid cells. The mastoid process serves for the attachment of the sternocleidomastoid, the posterior belly of the digastric muscle, splenius capitis, and longissimus capitis. On the medial side of the process is a deep groove, the mastoid notch, for the attachment of the digastric muscle; medial to this is a shallow furrow, the occipital groove, which lodges the occipital artery. The facial nerve passes close to the mastoid process.
Inner surface
The inner surface of the mastoid portion presents a deep, curved groove, the sigmoid sulcus, which lodges part of the transverse sinus; in it may be seen in the opening of the mastoid foramen.
The groove for the transverse sinus is separated from the in
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https://en.wikipedia.org/wiki/Petrous%20part%20of%20the%20temporal%20bone
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The petrous part of the temporal bone is pyramid-shaped and is wedged in at the base of the skull between the sphenoid and occipital bones. Directed medially, forward, and a little upward, it presents a base, an apex, three surfaces, and three angles, and houses in its interior, the components of the inner ear. The petrous portion is among the most basal elements of the skull and forms part of the endocranium. Petrous comes from the Latin word petrosus, meaning "stone-like, hard". It is one of the densest bones in the body. In other mammals, it is a separate bone, the petrosal bone.
The petrous bone is important for studies of ancient DNA from skeletal remains, as it tends to contain extremely well-preserved DNA.
Base
The base is fused with the internal surfaces of the squamous and mastoid parts.
Apex
The apex, which is rough and uneven, is received into the angular interval between the posterior border of the great wing of the sphenoid bone and the basilar part of the occipital bone; it presents the anterior or internal opening of the carotid canal, and forms the postero-lateral boundary of the foramen lacerum.
Surfaces
Anterior surface
The anterior surface forms the posterior part of the middle cranial fossa of the base of the skull, and is continuous with the inner surface of the squamous portion, to which it is united by the petrosquamous suture, remains of which are distinct even at a late period of life. It is marked by depressions for the convolutions of the brain, and presents six notable points:
near the center, the arcuate eminence (eminentia arcuata), which indicates the location of the superior semicircular canal.
in front of and a little lateral to this eminence, a depression indicating the position of the tympanic cavity: Here, the layer of bone that separates the tympanic from the cranial cavity is extremely thin, and is known as the tegmen tympani
a shallow groove, sometimes double, leading lateralward and backward to an oblique opening, th
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https://en.wikipedia.org/wiki/Tympanic%20part%20of%20the%20temporal%20bone
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The tympanic part of the temporal bone is a curved plate of bone lying below the squamous part of the temporal bone, in front of the mastoid process, and surrounding the external part of the ear canal.
It originates as a separate bone (tympanic bone), which in some mammals stays separate through life.
Evolutionarily, a portion of it is derived from the angular bone of the reptilian lower jaw.
Surfaces
Its postero-superior surface is concave, and forms the anterior wall, the floor, and part of the posterior wall of the bony ear canal.
Medially, it presents a narrow furrow, the tympanic sulcus, for the attachment of the tympanic membrane.
Its antero-inferior surface is quadrilateral and slightly concave; it constitutes the posterior boundary of the mandibular fossa, and is in contact with the retromandibular part of the parotid gland.
Borders
Its lateral border is free and rough, and gives attachment to the cartilaginous part of the ear canal. Internally, the tympanic part is fused with the petrous portion, and appears in the retreating angle between it and the squama, where it lies below and lateral to the orifice of the auditory tube. Posteriorly, it blends with the squama and mastoid part, and forms the anterior boundary of the tympanomastoid fissure.
Its upper border fuses laterally with the back of the postglenoid process, while medially it bounds the petrotympanic fissure.
The medial part of the lower border is thin and sharp; its lateral part splits to enclose the root of the styloid process, and is therefore named the vaginal process.
Ear canal
The central portion of the tympanic part is thin, as it gives rise to the bony inner two-thirds of the ear canal, and in 5 - 20% of skulls the lower surface is perforated by a hole, the foramen of Huschke that opens onto the temporomandibular joint due to incomplete fusion of the anterior and posterior prominences during development.
The bony portion of the ear canal is nearly 2 cm long and is directed inwa
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https://en.wikipedia.org/wiki/Temporal%20styloid%20process
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The temporal styloid process is a slender bony process of the temporal bone extending downward and forward from the undersurface of the temporal bone just below the ear. The styloid process gives attachments to several muscles, and ligaments.
Structure
The styloid process is a slender and pointed bony process of the temporal bone projecting anteroinferiorly from the inferior surface of the temporal bone just below the ear. Its length normally ranges from just under 3 cm to just over 4 cm. It is usually nearly straight, but may be curved in some individuals.
Its proximal (tympanohyal) part is ensheathed by the tympanic part of the temporal bone (vaginal process), whereas its distal (stylohyal) part gives attachment to several structures.
Attachments
The styloid process gives attachments to several muscles, and ligaments. It serves as an anchor point for several muscles associated with the tongue and larynx.
stylohyoid ligament
stylomandibular ligament
styloglossus muscle (innervated by the hypoglossal nerve)
stylohyoid muscle (innervated by the facial nerve)
stylopharyngeus muscle (innervated by the glossopharyngeal nerve)
Relations
The parotid gland is situated laterally to the styloid process, the external carotid artery passes by its apex, the facial nerve crosses its base, and the attachment of the stylopharyngeus muscle separates it from the internal jugular vein medially.
Clinical significance
A small percentage of the population will suffer from an elongation of the styloid process and stylohyoid ligament calcification. This condition is also known as Eagle syndrome. The tissues in the throat rub on the styloid process during the act of swallowing with resulting pain along the glossopharyngeal nerve. There is also pain upon turning the head or extending the tongue. Other symptoms may include voice alteration, cough, dizziness, migraines, occipital neuralgia, pain in teeth and jaw and sinusitis or bloodshot eyes.
Development
The styloid process a
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https://en.wikipedia.org/wiki/Connect%3ADirect
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Connect:Direct—originally named Network Data Mover (NDM)— is a computer software product that transfers files between mainframe computers and/or midrange computers. It was developed for mainframes, with other platforms being added as the product grew. NDM was renamed to Connect:Direct in 1993, following the acquisition of Systems Center, Inc. by Sterling Software. In 1996, Sterling Software executed a public spinoff of a new entity called Sterling Commerce, which consisted of the Communications Software Group (the business unit responsible for marketing the Connect:Direct product and other file transfer products sourced from the pre-1993 Sterling Software (e.g. Connect:Mailbox)) and the Sterling EDI Network business. In 2000, SBC Communications acquired Sterling Commerce and held it until 2010. AT&T merged with SBC effective November 2005. In 2010, IBM completed the purchase of Sterling Commerce from AT&T.
Technology
Traditionally, Sterling Connect:Direct used IBM's Systems Network Architecture (SNA) via dedicated private lines between the parties involved to transfer the data. In the early 1990s TCP/IP support was added. Connect:Direct's primary advantage over FTP was that it made file transfers routine and reliable.
IBM Sterling Connect:Direct is used within the financial services industry, government agencies and other large organizations that have multiple computing platforms: mainframes, midrange, Linux or Windows systems. In terms of speed, Connect:Direct typically performs slightly faster than FTP, reaching the maximum that the interconnecting link can support. If CPU cycles are available, Connect:Direct has several compression modes that can greatly enhance the throughput of the transfer, but care must be exercised in multi-processing environments as Connect:Direct can consume large amounts of processing cycles, impacting other workloads.
Connect:Direct originally did not support encrypted and secure data transfers, however an add-on, Connect:Direc
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https://en.wikipedia.org/wiki/Domestic%20canary
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The domestic canary, often simply known as the canary (Serinus canaria forma domestica), is a domesticated form of the wild canary, a small songbird in the finch family originating from the Macaronesian Islands (the Azores, Madeira and the Canary Islands).
Canaries were first bred in captivity in the 17th century, having been brought to Europe by Spanish sailors. This bird became expensive and fashionable to breed in courts of Spanish and English kings. Monks started breeding them and only sold the males (which sing). This kept the birds in short supply and drove the price up. Eventually, Italians obtained hens and were able to breed the birds. This made them very popular, resulting in many breeds arising, and the birds being bred all over Europe.
The same occurred in England. First the birds were only owned by the rich, but eventually the local citizens started to breed them and, again, they became very popular. Many breeds arose through selective breeding, and they are still very popular today for their voices.
From the 18th up to the 20th centuries, canaries and finches were used in the UK, Canada and the US in the coal mining industry to detect carbon monoxide. In the UK, this practice ceased in 1986.
Typically, the domestic canary is kept as a popular cage and aviary bird. Given proper housing and care, a canary's lifespan ranges from 10 to 15 years.
Etymology
The birds are named after Spain's Canary Islands, which derive their name from the Latin (after one of the larger islands, Gran Canaria), meaning 'island of dogs', due to its "vast multitudes of dogs of very large size".
Varieties
Domestic canaries are generally divided into three main groups:
Colour-bred canaries (bred for their many colour mutations – Ino, Eumo, Satinette, Bronze, Ivory, Onyx, Mosaic, Brown, red factor, Green (Wild Type): darkest black and brown melanin shade in yellow ground birds, Yellow Melanin: mutation showing yellow ground colour with brown and black pigment, Yellow Lipoch
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https://en.wikipedia.org/wiki/Basilar%20part%20of%20occipital%20bone
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The basilar part of the occipital bone (also basioccipital) extends forward and upward from the foramen magnum, and presents in front an area more or less quadrilateral in outline.
In the young skull this area is rough and uneven, and is joined to the body of the sphenoid by a plate of cartilage.
By the twenty-fifth year this cartilaginous plate is ossified, and the occipital and sphenoid form a continuous bone.
Surfaces
On its lower surface, about 1 cm. in front of the foramen magnum, is the pharyngeal tubercle which gives attachment to the fibrous raphe of the pharynx.
On either side of the middle line the longus capitis and rectus capitis anterior are inserted, and immediately in front of the foramen magnum the anterior atlantooccipital membrane is attached.
The upper surface, which constitutes the lower half of the clivus, presents a broad, shallow groove which inclines upward and forward from the foramen magnum; it supports the medulla oblongata, and near the margin of the foramen magnum gives attachment to the tectorial membrane
On the lateral margins of this surface are faint grooves for the inferior petrosal sinuses.
Additional images
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https://en.wikipedia.org/wiki/Lateral%20parts%20of%20occipital%20bone
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The lateral parts of the occipital bone (also called the exoccipitals) are situated at the sides of the foramen magnum; on their under surfaces are the condyles for articulation with the superior facets of the atlas.
Description
The condyles are oval or reniform (kidney-shaped) in shape, and their anterior extremities, directed forward and medialward, are closer together than their posterior, and encroach on the basilar portion of the bone; the posterior extremities extend back to the level of the middle of the foramen magnum.
The articular surfaces of the condyles are convex from before backward and from side to side, and look downward and lateralward.
To their margins are attached the capsules of the atlantoöccipital articulations, and on the medial side of each is a rough impression or tubercle for the alar ligament.
At the base of either condyle the bone is tunnelled by a short canal, the hypoglossal canal (anterior condyloid foramen).
This begins on the cranial surface of the bone immediately above the foramen magnum, and is directed lateralward and forward above the condyle.
It may be partially or completely divided into two by a spicule of bone; it gives exit to the hypoglossal or twelfth cerebral nerve, and entrance to a meningeal branch of the ascending pharyngeal artery.
Behind either condyle is a depression, the condyloid fossa, which receives the posterior margin of the superior facet of the atlas when the head is bent backward; the floor of this fossa is sometimes perforated by the condyloid canal, through which an emissary vein passes from the transverse sinus.
Extending lateralward from the posterior half of the condyle is a quadrilateral plate of bone, the jugular process, excavated in front by the jugular notch, which, in the articulated skull, forms the posterior part of the jugular foramen.
The jugular notch may be divided into two by a bony spicule, the intrajugular process, which projects lateralward above the hypoglossal canal.
The un
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https://en.wikipedia.org/wiki/Squamous%20part%20of%20occipital%20bone
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The squamous part of occipital bone is situated above and behind the foramen magnum, and is curved from above downward and from side to side.
External surface
The external surface is convex and presents midway between the summit of the bone and the foramen magnum a prominence, the external occipital protuberance and inion.
Extending lateralward from this on either side are two curved lines, one a little above the other. The upper, often faintly marked, is named the highest nuchal line, and to it the epicranial aponeurosis is attached.
The lower is termed the superior nuchal line. That area of the squamous part, which lies above the highest nuchal lines is named the occipital plane (planum occipitale) and is covered by the occipitalis muscle. That below, termed the nuchal plane, is rough and irregular for the attachment of several muscles.
From the external occipital protuberance, an often faintly marked ridge or crest, the median nuchal line, descends to the foramen magnum and affords attachment to the nuchal ligament. Running from the middle of this line across either half of the nuchal plane is the inferior nuchal line.
Several muscles are attached to the outer surface of the squamous part, thus the superior nuchal line gives origin to the occipitalis and trapezius muscles, and insertion to the sternocleidomastoid and splenius capitis muscles. Into the surface between the superior and inferior nuchal lines the semispinalis capitis and the obliquus capitis superior are inserted, while the inferior nuchal line and the area below it receive the insertions of the rectus capitis posterior major and minor.
The posterior atlantooccipital membrane is attached around the postero-lateral part of the foramen magnum, just outside the margin of the foramen.
Internal surface
The internal surface is deeply concave and divided into four fossae by the cruciform eminence.
The upper two fossae are triangular and lodge the occipital lobes of the cerebrum; the lower two are
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https://en.wikipedia.org/wiki/Meta-learning%20%28computer%20science%29
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Meta learning
is a subfield of machine learning where automatic learning algorithms are applied to metadata about machine learning experiments. As of 2017, the term had not found a standard interpretation, however the main goal is to use such metadata to understand how automatic learning can become flexible in solving learning problems, hence to improve the performance of existing learning algorithms or to learn (induce) the learning algorithm itself, hence the alternative term learning to learn.
Flexibility is important because each learning algorithm is based on a set of assumptions about the data, its inductive bias. This means that it will only learn well if the bias matches the learning problem. A learning algorithm may perform very well in one domain, but not on the next. This poses strong restrictions on the use of machine learning or data mining techniques, since the relationship between the learning problem (often some kind of database) and the effectiveness of different learning algorithms is not yet understood.
By using different kinds of metadata, like properties of the learning problem, algorithm properties (like performance measures), or patterns previously derived from the data, it is possible to learn, select, alter or combine different learning algorithms to effectively solve a given learning problem. Critiques of meta learning approaches bear a strong resemblance to the critique of metaheuristic, a possibly related problem. A good analogy to meta-learning, and the inspiration for Jürgen Schmidhuber's early work (1987) and Yoshua Bengio et al.'s work (1991), considers that genetic evolution learns the learning procedure encoded in genes and executed in each individual's brain. In an open-ended hierarchical meta learning system using genetic programming, better evolutionary methods can be learned by meta evolution, which itself can be improved by meta meta evolution, etc.
Definition
A proposed definition for a meta learning system combines three
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https://en.wikipedia.org/wiki/Amniocyte
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An amniocyte (literally "lamb cell") is a cell of a fetus which is suspended in the amniotic fluid.
To study a person's chromosomes, it can be used in DNA-based analysis, via microscopic analysis of the cells in amniotic fluid. After circa 16 weeks of pregnancy the fluid can be collected. It then contains shed fetal cells, which are put in culture and grow out slow. After around 2 weeks of culture the cells should have divided enough for proper DNA analysis.
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https://en.wikipedia.org/wiki/Squamous%20part%20of%20the%20frontal%20bone
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The squamous part of the frontal bone is the superior (approximately two thirds) portion when viewed in standard anatomical orientation. There are two surfaces of the squamous part of the frontal bone: the external surface, and the internal surface.
External surface
The external surface is convex and usually exhibits, in the lower part of the middle line, the remains of the frontal suture; in infancy this suture divides the frontal bone into two and later fuses. A condition where fusion has not taken place, may persist throughout life and is referred to as a metopic suture.
On either side of this suture, about 3 cm. above the supraorbital margin, is a rounded elevation, the frontal eminence (tuber frontale).
These eminences vary in size in different individuals, are occasionally unsymmetrical, and are especially prominent in young skulls; the surface of the bone above them is smooth, and covered by the epicranial aponeurosis.
Below the frontal eminences, and separated from them by a shallow groove, are two arched elevations, the superciliary arches; these are prominent medially, and are joined to one another by a smooth elevation named the glabella. They are larger in the male than in the female, and their degree of prominence depends to some extent on the size of the frontal air sinuses; prominent ridges are, however, occasionally associated with small air sinuses.
Beneath each superciliary arch is a curved and prominent margin, the supraorbital margin, which forms the upper boundary of the base of the orbit, and separates the squamous part from the orbital portion of the bone.
The lateral part of this margin is sharp and prominent, affording to the eye, in that situation, considerable protection from injury; the medial part is rounded.
At the junction of its medial and intermediate thirds is a notch, sometimes converted into a foramen, the supraorbital notch or foramen, which transmits the supraorbital vessels and nerve.
A small aperture in the upper part
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https://en.wikipedia.org/wiki/Vincent%20Wigglesworth
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Sir Vincent Brian Wigglesworth CBE FRS (17 April 1899 – 11 February 1994) was a British entomologist who made significant contributions to the field of insect physiology. He established the field in a textbook which was updated in a number of editions.
In particular, he studied metamorphosis. His most significant contribution was the discovery that neurosecretory cells in the brain of the South American kissing bug, Rhodnius prolixus, secrete a crucial hormone that triggers the prothoracic gland to release prothoracicotropic hormone (PTTH), which regulates the process of metamorphosis. This was the first experimental confirmation of the function of neurosecretory cells. He went on to discover another hormone, called the juvenile hormone, which prevented the development of adult characteristics in R. prolixus until the insect had reached the appropriate larval stage. Wigglesworth was able to distort the developmental phases of the insect by controlling levels of this hormone. From these observations, Wigglesworth was able to develop a coherent theory of how an insect's genome can selectively activate hormones which determine its development and morphology.
Personal life
Wigglesworth served in the Royal Field Artillery in France in World War I. He received his degree from the University of Cambridge and lectured at the London School of Hygiene and Tropical Medicine, the University of London, and finally at the University of Cambridge.
He was named Quick Professor of Biology at the University of Cambridge in 1952, appointed CBE in 1951, and knighted in 1964.
Wigglesworth was President of the Royal Entomological Society from 1963 to 1964 and the Association of Applied Biologists from 1966 to 1967. He was elected to the American Academy of Arts and Sciences in 1960, the United States National Academy of Sciences in 1971, and the American Philosophical Society in 1982.
He married Mable K Semple in St Albans in 1922. They had four children.
The bacterium Wiggleswor
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https://en.wikipedia.org/wiki/Hydride%20vapour-phase%20epitaxy
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Hydride vapour-phase epitaxy (HVPE) is an epitaxial growth technique often employed to produce semiconductors such as GaN, GaAs, InP and their related compounds, in which hydrogen chloride is reacted at elevated temperature with the group-III metals to produce gaseous metal chlorides, which then react with ammonia to produce the group-III nitrides. Carrier gasses commonly used include ammonia, hydrogen and various chlorides.
HVPE technology can significantly reduce the cost of production compared to the most common method of vapor deposition of organometallic compounds (MOCVD). Cost reduction is achieved by significantly reducing the consumption of NH3, cheaper source materials than in MOCVD, reducing the capital equipment costs, due to the high growth rate.
Developed in the 1960s, it was the first epitaxial method used for the fabrication of single GaN crystals.
Hydride vapour-phase epitaxy (HVPE) is the only III–V and III–N semiconductor crystal growth process working close to equilibrium. This means that the condensation reactions exhibit fast kinetics: one observes immediate reactivity to an increase of the vapour-phase supersaturation towards condensation. This property is due to the use of chloride vapour precursors GaCl and InCl, of which dechlorination frequency is high enough so that there is no kinetic delay. A wide range of growth rates, from 1 to 100 micrometers per hour, can then be set as a function of the vapour-phase supersaturation. Another HVPE feature is that growth is governed by surface kinetics: adsorption of gaseous precursors, decomposition of ad-species, desorption of decomposition products, surface diffusion towards kink sites. This property is of benefit when it comes to selective growth on patterned substrates for the synthesis of objects and structures exhibiting a 3D morphology. The morphology is only dependent on the intrinsic growth anisotropy of crystals. By setting experimental growth parameters of temperature and composition of
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https://en.wikipedia.org/wiki/Countercurrent%20multiplication
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A countercurrent mechanism system is a mechanism that expends energy to create a concentration gradient.
It is found widely in nature and especially in mammalian organs. For example, it can refer to the process that is underlying the process of urine concentration, that is, the production of hyperosmotic urine by the mammalian kidney. The ability to concentrate urine is also present in birds.
Countercurrent multiplication is frequently mistaken for countercurrent exchange, a similar but different mechanism where gradients are maintained, but not established.
Physiological principles
The term derives from the form and function of the loop of Henle, which consists of two parallel limbs of renal tubules running in opposite directions, separated by the interstitial space of the renal medulla.
The descending limb of the loop of Henle is permeable to water but impermeable to solutes, due to the presence of aquaporin 1 in its tubular wall. Thus, water moves across the tubular wall into the medullary space, making the filtrate hypertonic (with a lower water potential). This is the filtrate that continues to the ascending limb.
The ascending limb is impermeable to water (because of a lack of aquaporin, a common transporter protein for water channels in all cells except the walls of the ascending limb of the loop of Henle) but permeable to solutes, but here Na+, Cl−, and K+ are actively transported into the medullary space, making the filtrate hypotonic (with a higher water potential). The interstitium is now "salty" or hypertonic, and will attract water as below. This constitutes the single effect of the countercurrent multiplication process.
Active transport of these ions from the thick ascending limb creates an osmotic pressure drawing water from the descending limb into the hyperosmolar medullary space, making the filtrate hypertonic (with a lower water potential).
The countercurrent flow within the descending and ascending limb thus increases, or multiplies th
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https://en.wikipedia.org/wiki/Kazuya%20Kato
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is a Japanese mathematician who works at the University of Chicago and specializes in number theory and arithmetic geometry.
Early life and education
Kazuya Kato grew up in the prefecture of Wakayama in Japan. He attended college at the University of Tokyo, from which he also obtained his master's degree in 1975, and his PhD in 1980.
Career
Kato was a professor at Tokyo University, Tokyo Institute of Technology and Kyoto University. He joined the faculty of the University of Chicago in 2009.
A special volume of Documenta Mathematica was published in honor of his 50th birthday, together with research papers written by leading number theorists and former students it contains Kato's song on Prime Numbers.
Research
Kato's first work was in the higher-dimensional generalisations of local class field theory using algebraic K-theory. His theory was then extended to higher global class field theory in which several of his papers were written jointly with Shuji Saito.
He contributed to various other areas such as p-adic Hodge theory, logarithmic geometry (he was one of its creators together with Jean-Marc Fontaine and Luc Illusie), comparison conjectures, special values of zeta functions including applications to the Birch-Swinnerton-Dyer conjecture, the Bloch-Kato conjecture on Tamagawa numbers, and Iwasawa theory.
Awards and honors
In 2005, Kato received the Imperial Prize of the Japan Academy for "Research on Arithmetic Geometry".
Books
Kato has published several books in Japanese, of which some have already been translated into English.
He wrote a book on Fermat's Last Theorem and is also the coauthor of two volumes of the trilogy on Number Theory, which have been translated into English.
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https://en.wikipedia.org/wiki/Endocannabinoid%20system
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The endocannabinoid system (ECS) is a biological system composed of endocannabinoids, which are endogenous lipid-based retrograde neurotransmitters that bind to cannabinoid receptors (CBRs), and cannabinoid receptor proteins that are expressed throughout the vertebrate central nervous system (including the brain) and peripheral nervous system. The endocannabinoid system remains under preliminary research, but may be involved in regulating physiological and cognitive processes, including fertility, pregnancy, pre- and postnatal development, various activity of immune system, appetite, pain-sensation, mood, and memory, and in mediating the pharmacological effects of cannabis. The ECS plays an important role in multiple aspects of neural functions, including the control of movement and motor coordination, learning and memory, emotion and motivation, addictive-like behavior and pain modulation, among others.
Two primary cannabinoid receptors have been identified: CB1, first cloned (or isolated) in 1990; and CB2, cloned in 1993. CB1 receptors are found predominantly in the brain and nervous system, as well as in peripheral organs and tissues, and are the main molecular target of the endogenous partial agonist, anandamide (AEA), as well as exogenous THC, the most known active component of cannabis. Endocannabinoid 2-arachidonoylglycerol (2-AG), which was found to be two and three orders of magnitude more abundant in mammalian brain than AEA, acts as a full agonist at both CB receptors.
Basic overview
The endocannabinoid system, broadly speaking, includes:
The endogenous arachidonate-based lipids, anandamide (N-arachidonoylethanolamide) and 2-AG, besides other N-acylethanolamines (NAEs); these are known as "endocannabinoids" and are physiological ligands for the cannabinoid receptors. Endocannabinoids are all eicosanoids.
The enzymes that synthesize and degrade the endocannabinoids, such as fatty acid amide hydrolase or monoacylglycerol lipase.
The cannabinoid recep
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https://en.wikipedia.org/wiki/Comparison%20of%20VoIP%20software
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This is a comparison of voice over IP (VoIP) software used to conduct telephone-like voice conversations across Internet Protocol (IP) based networks. For residential markets, voice over IP phone service is often cheaper than traditional public switched telephone network (PSTN) service and can remove geographic restrictions to telephone numbers, e.g., have a PSTN phone number in a New York area code ring in Tokyo.
For businesses, VoIP obviates separate voice and data pipelines, channelling both types of traffic through the IP network while giving the telephony user a range of advanced abilities.
Softphones are client devices for making and receiving voice and video calls over the IP network with the standard functions of most original telephones and usually allow integration with VoIP phones and USB phones instead of using a computer's microphone and speakers (or headset). Most softphone clients run on the open Session Initiation Protocol (SIP) supporting various codecs. Skype runs on a closed proprietary networking protocol but additional business telephone system (PBX) software can allow a SIP based telephone system to connect to the Skype network. Online chat programs now also incorporate voice and video communications.
Other VoIP software applications include conferencing servers, intercom systems, virtual foreign exchange services (FXOs) and adapted telephony software which concurrently support VoIP and public switched telephone network (PSTN) like Interactive Voice Response (IVR) systems, dial in dictation, on hold and call recording servers.
Some entries below are Web-based VoIP; most are standalone Desktop applications.
Desktop applications
Discontinued softphone service
Mobile phones
For mobile VoIP clients:
Frameworks and libraries
Server software
Secure VoIP software
VoIP software with client-to-client encryption
The following table is an overview of those VoIP clients which (can) provide end-to-end encryption.
VoIP software with client-to-
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https://en.wikipedia.org/wiki/Leyland%20number
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In number theory, a Leyland number is a number of the form
where x and y are integers greater than 1. They are named after the mathematician Paul Leyland. The first few Leyland numbers are
8, 17, 32, 54, 57, 100, 145, 177, 320, 368, 512, 593, 945, 1124 .
The requirement that x and y both be greater than 1 is important, since without it every positive integer would be a Leyland number of the form x1 + 1x. Also, because of the commutative property of addition, the condition x ≥ y is usually added to avoid double-covering the set of Leyland numbers (so we have 1 < y ≤ x).
Leyland primes
A Leyland prime is a Leyland number that is also a prime. The first such primes are:
17, 593, 32993, 2097593, 8589935681, 59604644783353249, 523347633027360537213687137, 43143988327398957279342419750374600193, ...
corresponding to
32+23, 92+29, 152+215, 212+221, 332+233, 245+524, 563+356, 3215+1532.
One can also fix the value of y and consider the sequence of x values that gives Leyland primes, for example x2 + 2x is prime for x = 3, 9, 15, 21, 33, 2007, 2127, 3759, ... ().
By November 2012, the largest Leyland number that had been proven to be prime was 51226753 + 67535122 with 25050 digits. From January 2011 to April 2011, it was the largest prime whose primality was proved by elliptic curve primality proving. In December 2012, this was improved by proving the primality of the two numbers 311063 + 633110 (5596 digits) and 86562929 + 29298656 (30008 digits), the latter of which surpassed the previous record. There are many larger known probable primes such as 3147389 + 9314738, but it is hard to prove primality of large Leyland numbers. Paul Leyland writes on his website: "More recently still, it was realized that numbers of this form are ideal test cases for general purpose primality proving programs. They have a simple algebraic description but no obvious cyclotomic properties which special purpose algorithms can exploit."
There is a project called XYYXF to factor composite
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https://en.wikipedia.org/wiki/Telenet
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Telenet was an American commercial packet-switched network which went into service in 1975. It was the first FCC-licensed public data network in the United States. Various commercial and government interests paid monthly fees for dedicated lines connecting their computers and local networks to this backbone network. Free public dialup access to Telenet, for those who wished to access these systems, was provided in hundreds of cities throughout the United States.
The original founding company, Telenet Inc., was established by Bolt Beranek and Newman (BBN) and recruited Larry Roberts (former head of the ARPANet) as President of the company, and Barry Wessler. GTE acquired Telenet in 1979. It was later acquired by Sprint and called "Sprintnet". Sprint migrated customers from Telenet to the modern-day Sprintlink IP network, one of many networks composing today's Internet.
Telenet had its first offices in downtown Washington, D.C., then moved to McLean, Virginia. It was acquired by GTE while in McLean, and then moved to offices in Reston, Virginia.
History
After establishing that commercial operation of "value added carriers" was legal in the U.S., Bolt Beranek and Newman (BBN), who were the private contractors for the ARPANET, set out to create a private sector version. In January 1975, Telenet Communications Corporation announced that they had acquired the necessary venture capital after a two-year quest, and on August 16 of the same year they began operating the first public data network.
Coverage
Originally, the public network had switching nodes in seven US cities:
Washington, D.C. (network operations center as well as switching)
Boston, Massachusetts
New York, New York
Chicago, Illinois
Dallas, Texas
San Francisco, California
Los Angeles, California
The switching nodes were fed by Telenet Access Controller (TAC) terminal concentrators both colocated and remote from the switches. By 1980, there were over 1000 switches in the public network. At that time, t
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https://en.wikipedia.org/wiki/Serosorting
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Serosorting, also known as serodiscrimination, is the practice of using HIV status as a decision-making point in choosing sexual behavior. The term is used to describe the behavior of a person who chooses a sexual partner assumed to be of the same HIV serostatus in order to engage in unprotected sex with them for a reduced risk of acquiring or transmitting HIV/AIDS.
Knowledge of HIV status is based on the result of a person's HIV test, with a positive result indicating that a person has HIV, and can potentially transmit the disease to others during any sexual contact involving an exchange of bodily fluids (e.g., unprotected anal or vaginal sex). There are many situations where determining their partner's serostatus outside of clinical settings cannot be done with complete certainty, limiting the efficacy in mitigating the transmission of HIV/AIDS (or other STIs). As people do not typically engage in sex practices with the expectation of contracting or transmitting HIV, failed attempts at serosorting are a leading cause of the contraction of HIV among partners.
Terms and etymology
The word serosorting comes from the Latin word serum, which refers to blood serum. Sorting refers to choosing partners based on HIV status, which can be determined from blood tests, among other methods. Serodiscordant sex refers to sex between an HIV-positive person and an HIV-negative person. Typically, partners practicing serosorting make an attempt to find someone with a matching HIV test result, otherwise known as a seroconcordant partner.
Risks
Failure to accurately determine HIV status
Failure to accurately determine HIV status may stem from people not being sure of their true HIV status or not admitting to having HIV. A recent negative result from an HIV test may not be definitive of a person's serostatus, because if they are still within the window period following a recent infection, the antibodies that the blood tests measure will not be present yet. In addition, testing negat
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https://en.wikipedia.org/wiki/Caenogenesis
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Caenogenesis (also variously spelled cenogenesis, kainogenesis, kenogenesis) is the introduction during embryonic development of characters or structure not present in the earlier evolutionary history of the strain or species, as opposed to palingenesis. Notable examples include the addition of the placenta in mammals.
Caenogenesis constitutes a violation to Ernst Haeckel's biogenetic law and was explained by Haeckel as adaptation to the peculiar conditions of the organism's individual development. Other authorities, such as Wilhelm His, Sr., on the contrary saw embryonic differences as precursors to adult differences.
See also
Ontogeny
Recapitulation theory
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https://en.wikipedia.org/wiki/Zapple%20Monitor
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The Zapple Monitor was a firmware-based product developed by Roger Amidon at Technical Design Laboratories (also known as TDL). TDL was based in Princeton, New Jersey, USA in the 1970s and early 1980s.
The Zapple monitor was a primitive operating system which could be expanded and used as a Basic Input/Output Services (BIOS) 8080 and Z80 based computers. Much of the functionality of Zapple would find its way into applications like 'Debug' in MS-DOS.
Zapple commands would allow a user to examine and modify memory, I/O, execute software (Goto or Call) and had a variety of other commands. The program required little in the way of then expensive Read Only Memory or RAM. An experienced user could use Zapple to test and debug code, verify hardware function, test memory, and so on.
A typical command line would start with a letter such as 'X' (examine memory) followed by a hexadecimal word (the memory address 01AB) and [enter] or [space]. After this sequence the content of the memory location would be shown [FF] and the user could enter a hexadecimal byte [00] to replace the contents of the address, or hit [space] or [enter] to move to the next address [01AB]. An experienced user could enter a small program in this manner, entering machine language from memory.
Because of the simple structure of the program, consisting of a vector table (one for each letter) and a small number of subroutines, and because the source code was readily available, adding or modifying Zapple was straightforward. The dominant operating system of the era, CP/M, required the computer manufacturer or hobbyist to develop hardware specific BIOS. Many users tested their BIOS subroutines using Zapple to verify, for example, a floppy disk track seek command, or read sector command, etc., was functioning correctly by extending Zapple to accommodate these operations in the hardware environment.
The general structure of Zapple lives on in the code of many older programmers working on embedded systems a
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https://en.wikipedia.org/wiki/Gross%20motor%20skill
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Gross motor skills are the abilities usually acquired during childhood as part of a child's motor learning. By the time they reach two years of age, almost all children are able to stand up, walk and run, walk up stairs, etc. These skills are built upon, improved and better controlled throughout early childhood, and continue in refinement throughout most of the individual's years of development into adulthood. These gross movements come from large muscle groups and whole body movement. These skills develop in a head-to-toe order. The children will typically learn head control, trunk stability, and then standing up and walking. It is shown that children exposed to outdoor play time activities will develop better gross motor skills.
Types of motor skills
Motor skills are movements and actions of the muscles. Typically, they are categorized into two groups: gross motor skills and fine motor skills. Gross motor skills are involved in movement and coordination of the arms, legs, and other large body parts and movements. Gross motor skills can be further divided into two subgroups of locomotor skills and object control skills. Gross locomotor skills would include running, jumping, sliding, and swimming. Object control skills would include throwing, catching and kicking. Fine motor skills are involved in smaller movements that occur in the wrists, hands, fingers, and the feet and toes. They participate in smaller actions such as picking up objects between the thumb and finger, writing carefully, and even blinking. These two motor skills work together to provide coordination. Less developed children focus on their gross movements, while more developed children have more control over their fine movements.
Development of posture
Gross motor skills, as well as many other activities, require postural control. Infants need to control the heads to stabilize their gaze and to track moving objects. They also must have strength and balance in their legs to walk.
Newborn infants c
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https://en.wikipedia.org/wiki/Taylor%20knock-out%20factor
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The Taylor knock-out factor, also called Taylor KO factor or TKOF, is a formulaic mathematical approach for evaluating the stopping power of hunting cartridges, developed by John "Pondoro" Taylor in the middle of the 20th century. Taylor, an elephant hunter and author who wrote two books about rifles and cartridges for African hunting, devised the formula as a means of comparing the ability of a cartridge to deliver a knock out blow to elephant from a shot to the head when the brain is missed.
Formula
The Taylor KO factor multiplies bullet mass (measured in grains) by muzzle velocity (measured in feet per second) by bullet diameter (measured in inches) and then divides the product by 7,000, converting the value from grains to pounds and giving a numerical value from 0 to ~150 for normal hunting cartridges. It is proportional to the momentum at the muzzle times the diameter of the bullet. Expressed as a fraction, the Taylor KO Factor is:
Example calculation
Using the standard 7.62×51mm NATO cartridge, the cartridge's characteristics are:
Bullet mass = 9.5 grams 147 grains
Muzzle velocity = 833 meters per second 2733 feet per second
Bullet diameter = 7.82 millimetres .308 inches
The calculation is:
Therefore the Taylor KO factor for the 7.62x51mm NATO cartridge is 17.7.
For metric values the calculation is :
7.62×51mm NATO in metric :
(note that 7.62mm is the land diameter of the caliber, however the actual bullet diam is 7,82mm)
Note: The product of mass and velocity is a quantity called, in modern physics, "momentum". Conservation of momentum is a characteristic of non-deformable collisions. A bullet, hitting hard bone, would transfer most of the impulse to that bone mass.
History
John "Pondoro" Taylor, an ivory hunter who over his career shot over 1,000 elephants along with a variety of other African game and who is renowned for writing two books about rifles and cartridges for African hunting, devised the Taylor KO factor to place a mathematical v
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https://en.wikipedia.org/wiki/Thigmonasty
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In biology, thigmonasty or seismonasty is the nastic (non-directional) response of a plant or fungus to touch or vibration. Conspicuous examples of thigmonasty include many species in the leguminous subfamily Mimosoideae, active carnivorous plants such as Dionaea and a wide range of pollination mechanisms.
Distinctive aspects
Thigmonasty differs from thigmotropism in that nastic motion is independent of the direction of the stimulus. For example, tendrils from a climbing plant are thigmotropic because they twine around any support they touch, responding in whichever direction the stimulus came from. However, the shutting of a venus fly trap is thigmonastic; no matter what the direction of the stimulus, the trap simply shuts (and later possibly opens).
The time scales of thigmonastic responses tend to be shorter than those of thigmotropic movements because many examples of thigmonasty depend on pre-accumulated turgor or on bistable mechanisms rather than growth or cell division. Certain dramatic examples of rapid plant movement such as the sudden drooping of Mimosa pudica or the trapping action of Dionaea or Utricularia are fast enough to observe without time lapse photography; some take less than a second. Speed is no clear distinction however; for example the re-erection of Mimosa leaves is nastic, but typically takes some 15 to 30 minutes, rather than a second or so. Similarly, re-opening of the Dionaea trap, though also nastic, typically takes days to complete.
Botanical physiologists have discovered signalling molecules called turgorins, that help mediate the loss of turgor. In species with the fastest response time, vacuoles are believed to provide temporary, high speed storage for calcium ions.
Examples of plants exhibiting thigmonasty
In the Asteraceae
Thigmonasty other than leaf closure occurs in various species of thistles. When an insect lands on a flower, the anthers shrink and rebound, loading the insect with pollen. The effect results from turgor
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https://en.wikipedia.org/wiki/Image%20gradient
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An image gradient is a directional change in the intensity or color in an image. The gradient of the image is one of the fundamental building blocks in image processing. For example, the Canny edge detector uses image gradient for edge detection. In graphics software for digital image editing, the term gradient or color gradient is also used for a gradual blend of color which can be considered as an even gradation from low to high values, as used from white to black in the images to the right. Another name for this is color progression.
Mathematically, the gradient of a two-variable function (here the image intensity function) at each image point is a 2D vector with the components given by the derivatives in the horizontal and vertical directions. At each image point, the gradient vector points in the direction of largest possible intensity increase, and the length of the gradient vector corresponds to the rate of change in that direction.
Since the intensity function of a digital image is only known at discrete points, derivatives of this function cannot be defined unless we assume that there is an underlying continuous intensity function which has been sampled at the image points. With some additional assumptions, the derivative of the continuous intensity function can be computed as a function on the sampled intensity function, i.e., the digital image. Approximations of these derivative functions can be defined at varying degrees of accuracy. The most common way to approximate the image gradient is to convolve an image with a kernel, such as the Sobel operator or Prewitt operator.
Image gradients are often utilized in maps and other visual representations of data in order to convey additional information. GIS tools use color progressions to indicate elevation and population density, among others.
Computer vision
In computer vision, image gradients can be used to extract information from images. Gradient images are created from the original image (generally
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https://en.wikipedia.org/wiki/Family-wise%20error%20rate
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In statistics, family-wise error rate (FWER) is the probability of making one or more false discoveries, or type I errors when performing multiple hypotheses tests.
Familywise and Experimentwise Error Rates
John Tukey developed in 1953 the concept of a familywise error rate as the probability of making a Type I error among a specified group, or "family," of tests. Ryan (1959) proposed the related concept of an experimentwise error rate, which is the probability of making a Type I error in a given experiment. Hence, an experimentwise error rate is a familywise error rate for all of the tests that are conducted within an experiment.
As Ryan (1959, Footnote 3) explained, an experiment may contain two or more families of multiple comparisons, each of which relates to a particular statistical inference and each of which has its own separate familywise error rate. Hence, familywise error rates are usually based on theoretically informative collections of multiple comparisons. In contrast, an experimentwise error rate may be based on a co-incidental collection of comparisons that refer to a diverse range of separate inferences. Consequently, some have argued that it may not be useful to control the experimentwise error rate. Indeed, Tukey was against the idea of experimentwise error rates (Tukey, 1956, personal communication, in Ryan, 1962, p. 302). More recently, Rubin (2021) criticised the automatic consideration of experimentwise error rates, arguing that “in many cases, the joint studywise [experimentwise] hypothesis has no relevance to researchers’ specific research questions, because its constituent hypotheses refer to comparisons and variables that have no theoretical or practical basis for joint consideration.”
Background
Within the statistical framework, there are several definitions for the term "family":
Hochberg & Tamhane (1987) defined "family" as "any collection of inferences for which it is meaningful to take into account some combined measure of error"
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https://en.wikipedia.org/wiki/Window%20period
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In medicine, the window period for a test designed to detect a specific disease (particularly infectious disease) is the time between first infection and when the test can reliably detect that infection. In antibody-based testing, the window period is dependent on the time taken for seroconversion.
The window period is important to epidemiology and safe sex strategies, and in blood and organ donation, because during this time, an infected person or animal cannot be detected as infected but may still be able to infect others. For this reason, the most effective disease-prevention strategies combine testing with a waiting period longer than the test's window period.
Examples
HIV
The window period for HIV may be up to three months, depending on the test method and other factors. RNA based HIV tests has the lowest window period. Modern and accurate testing abilities can cut this period to 25 days, 16 days, or even as low as 12 days, again, depending on the type of test and the quality of its administration and interpretation.
Hepatitis B
Two periods may be referred to as window period in hepatitis B infection:
(1) the period that elapses during HBsAg to HBsAb seroconversion, i.e. between the disappearance of surface antigen (HBsAg) from serum and the appearance of HBsAb (anti-HBs), and
(2) the period between infection and appearance of HBsAg.
During the window of HBsAg to HBsAb seroconversion, IgM anti-core (HBc-IgM) is the only detectable antibody. HBV DNA may be positive as well. This window period does not occur in persons who develop chronic hepatitis B, i.e. who continue to have detectable HBV DNA for greater than 6 months (HbsAg remains positive), or in people who develop isolated HBcAb positivity, i.e. who lose HBsAg, but do not develop HBsAb (HBV DNA may or may not remain positive).
See also
Incubation period, the time between infection and the appearance of symptoms
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https://en.wikipedia.org/wiki/Community%20Memory
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Community Memory (CM) was the first public computerized bulletin board system. Established in 1973 in Berkeley, California, it used an SDS 940 timesharing system in San Francisco connected via a 110 baud link to a teleprinter at a record store in Berkeley to let users enter and retrieve messages. Individuals could place messages in the computer and then look through the memory for a specific notice.
While initially conceived as an information and resource sharing network linking a variety of counter-cultural economic, educational, and social organizations with each other and the public, Community Memory was soon generalized to be an information flea market, by providing unmediated, two-way access to message databases through public computer terminals. Once the system became available, the users demonstrated that it was a general communications medium that could be used for art, literature, journalism, commerce, and social chatter.
People
Community Memory was created by Lee Felsenstein, Efrem Lipkin, Ken Colstad, Jude Milhon, and Mark Szpakowski, acting as The Community Memory Project within the Resource One computer center at Project One in San Francisco. This group of computer savvy friends and partners wanted to create a simple system that could function as a source of community information. Felsenstein took care of hardware, Lipkin software, and Szpakowski user interface and information husbandry. Community Memory in its first phase (1973–1975) was an experiment to see how people would react to using a computer to exchange information. At that time few people had any direct contact with computers. CM was conceived as a tool to help strengthen the Berkeley community. Their brochure states that "strong, free, non-hierarchical channels of communication--whether by computer and modem, pen and ink, telephone, or face-to-face--are the front line of reclaiming and revitalizing our communities."
The creators and founders of Community Memory shared the values of north
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https://en.wikipedia.org/wiki/Portapak
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A Portapak is a battery-powered, self-contained video tape analog recording system. Introduced to the market in 1967, it could be carried and operated by one person.
Earlier television cameras were large and heavy, required a specialized vehicle for transportation, and were mounted on a pedestal. The Portapak made it possible to shoot and record video easily outside of the studio without requiring a crew. Although it recorded at a lower quality than television studio cameras, the Portapak was adopted by both professionals and amateurs as a new method of video recording. Before Portapak cameras, remote television news footage was routinely photographed on 16mm film and telecined for broadcast.
The first portapak system, the Sony DV-2400 Video Rover, was a two-piece set consisting of a black-and-white composite video video camera and a separate record-only helical scan ½″ video tape recorder (VTR) unit. It required a Sony CV series VTR (such as the CV-2000) to play back the video. Following Sony’s introduction of the Video Rover, numerous other manufacturers sold their own versions of Portapak technology. Although it was light enough for a single person to carry and use, it was usually operated by a crew of two: one carrying and controlling the camera, and one carrying and operating the VTR.
This model was followed up by the AV-3400/AVC-3400, which used the EIAJ-1 format, and had 30-minute capacity, as well as playback capability. Later Portapaks by Sony, JVC, and others used such formats as U-Matic videocassettes (with reduced-size 20-minute "U-Matic S" cassettes) and Betacam SP (for which a Portapak, unlike a camera-mounted deck, allowed the use of the larger "L" cassettes, for up to 90-minute recording time).
The introduction of the Portapak had a great influence on the development of video art, guerrilla television, and activism. Video collectives such as TVTV and the Videofreex utilized Portapak technology to document countercultural movements apart from the
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https://en.wikipedia.org/wiki/Transient%20response
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In electrical engineering and mechanical engineering, a transient response is the response of a system to a change from an equilibrium or a steady state. The transient response is not necessarily tied to abrupt events but to any event that affects the equilibrium of the system. The impulse response and step response are transient responses to a specific input (an impulse and a step, respectively).
In electrical engineering specifically, the transient response is the circuit’s temporary response that will die out with time. It is followed by the steady state response, which is the behavior of the circuit a long time after an external excitation is applied.
Damping
The response can be classified as one of three types of damping that describes the output in relation to the steady-state response.
Underdamped
An underdamped response is one that oscillates within a decaying envelope. The more underdamped the system, the more oscillations and longer it takes to reach steady-state. Here damping ratio is always less than one.
Critically damped
A critically damped response is the response that reaches the steady-state value the fastest without being underdamped. It is related to critical points in the sense that it straddles the boundary of underdamped and overdamped responses. Here, the damping ratio is always equal to one. There should be no oscillation about the steady-state value in the ideal case.
Overdamped
An overdamped response is the response that does not oscillate about the steady-state value but takes longer to reach steady-state than the critically damped case. Here damping ratio is greater than one.
Properties
Transient response can be quantified with the following properties.
Rise time
Rise time refers to the time required for a signal to change from a specified low value to a specified high value. Typically, these values are 10% and 90% of the step height.
Overshoot
Overshoot is when a signal or function exceeds its target. It is often associated with ri
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https://en.wikipedia.org/wiki/List%20of%20longest-living%20organisms
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This is a list of the longest-living biological organisms: the individual(s) (or in some instances, clones) of a species with the longest natural maximum life spans. For a given species, such a designation may include:
The oldest known individual(s) that are currently alive, with verified ages.
Verified individual record holders, such as the longest-lived human, Jeanne Calment, or the longest-lived domestic cat, Creme Puff.
The definition of "longest-living" used in this article considers only the observed or estimated length of an individual organism's natural lifespan – that is, the duration of time between its birth or conception, or the earliest emergence of its identity as an individual organism, and its death – and does not consider other conceivable interpretations of "longest-living", such as the length of time between the earliest appearance of a species in the fossil record and the present (the historical "age" of the species as a whole), the time between a species' first speciation and its extinction (the phylogenetic "lifespan" of the species), or the range of possible lifespans of a species' individuals. This list includes long-lived organisms that are currently still alive as well as those that are dead.
Determining the length of an organism's natural lifespan is complicated by many problems of definition and interpretation, as well as by practical difficulties in reliably measuring age, particularly for extremely old organisms and for those that reproduce by asexual cloning. In many cases the ages listed below are estimates based on observed present-day growth rates, which may differ significantly from the growth rates experienced thousands of years ago. Identifying the longest-living organisms also depends on defining what constitutes an "individual" organism, which can be problematic, since many asexual organisms and clonal colonies defy one or both of the traditional colloquial definitions of individuality (having a distinct genotype and havin
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https://en.wikipedia.org/wiki/Beta-secretase%201
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Beta-secretase 1, also known as beta-site amyloid precursor protein cleaving enzyme 1, beta-site APP cleaving enzyme 1 (BACE1), membrane-associated aspartic protease 2, memapsin-2, aspartyl protease 2, and ASP2, is an enzyme that in humans is encoded by the BACE1 gene. Expression of BACE1 is observed mainly in neurons.
BACE1 is an aspartic acid protease important in the formation of myelin sheaths in peripheral nerve cells: in mice the expression of BACE1 is high in the postnatal stages, when myelination occurs. The transmembrane protein contains two active site aspartate residues in its extracellular protein domain and may function as a dimer, its cytoplasmic tail is required for the correct maturation and an efficient intracellular trafficking, but does not affect the activity. It is produced as a pro-enzyme, the endoproteolitc removal occurs after BACE leaves endoplasmic reticulum, in the Golgi apparatus. In addition the pro-peptide receives additional sugars to increase the molecular mass. and the tail became a palmitoylated.
The BACE1 expression is influenced by the inflammatory state: during AD the cytokines reduce the PPAR1 an inhibitor of BACE1 mRNA).
Role in Alzheimer's disease
BACE1 is the major beta secretase for the generation of amyloid-β peptides in the neurons.
Generation of the 40 or 42 amino acid-long amyloid-β peptides that aggregate in the brain of Alzheimer's patients requires two sequential cleavages of the amyloid precursor protein (APP). Extracellular cleavage of APP by BACE1 creates a soluble extracellular fragment and a cell membrane-bound fragment referred to as C99. Cleavage of C99 within its transmembrane domain by γ-secretase releases the intracellular domain of APP and produces amyloid-β. Since gamma-secretase cleaves APP closer to the cell membrane than BACE1 does, it removes a fragment of the amyloid-β peptide. Initial cleavage of APP by α-secretase rather than BACE1 prevents eventual generation of amyloid-β, forming P3, this de
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https://en.wikipedia.org/wiki/Nominal%20analogue%20blanking
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Nominal analogue blanking is the outermost part of the overscan of a standard definition digital television image. It consists of a gap of black (or nearly black) pixels at the left and right sides, which correspond to the end and start of the horizontal blanking interval: the front porch at the right side (the end of a line, before the sync pulse), and the back porch at the left side (the start of a line, after the sync pulse and before drawing the next line). Digital television ordinarily contains 720 pixels per line, but only 702 (PAL) to 704 (NTSC) of them contain picture content. The location is variable, since analogue equipment may shift the picture sideways in an unexpected amount or direction.
The exact width is determined by taking the definition of the time required for an active line in PAL or NTSC, and multiplying it by the pixel clock of 13.5 MHz of Digital SDTV. PAL is exactly 52μs, so it will equate to exactly 702 pixels.
Notably, screen shapes and aspect ratios were defined in an era of purely analogue broadcasting for TV. This means that any picture with nominal analogue blanking, whether it be 702, around 704, or less, will be — by definition — a 4:3 picture. Therefore, when cross-converting into a square-pixel environment (like MPEG-4 and its variants), this width must always scale to 768 (PAL) or 640 (NTSC). This has the outcome of causing a full picture of 720x576 or 720x480 to be wider than 4:3. In fact, a purely digitally sourced SDTV image, with no analogue blanking, will be close to 788x576 or 655x480 once stretched to square pixels.
Standard definition widescreen pictures were also defined in an analogue environment and must also be treated as such. This means that a purely digitally sourced widescreen SDTV image, with no analogue blanking, will be close to 1050x576 or 873x480.
For details, see the technical specifications of overscan amounts.
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https://en.wikipedia.org/wiki/Secretory%20protein
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A secretory protein is any protein, whether it be endocrine or exocrine, which is secreted by a cell. Secretory proteins include many hormones, enzymes, toxins, and antimicrobial peptides.
Secretory proteins are synthesized in the endoplasmic reticulum.
Production
The production of a secretory protein starts like any other protein. The mRNA is produced and transported to the cytosol where it interacts with a free cytosolic ribosome. The part that is produced first, the N-terminal, contains a signal sequence consisting of 6 to 12 amino acids with hydrophobic side chains. This sequence is recognised by a cytosolic protein, SRP (Signal Recognition Particle), which stops the translation and aids in the transport of the mRNA-ribosome complex to an SRP receptor found in the membrane of the endoplasmic reticulum. When it arrives at the ER, the signal sequence is transferred to the translocon, a protein-conducting channel in the membrane that allows the newly synthesized polypeptide to be translocated to the ER lumen. The dissociation of SRP from the ribosome restores the translation of the secretory protein. The signal sequence is removed and the translation continues while the produced chain moves through the translocon (cotranslational translocation).
Modification
After the production of the protein is completed, it interacts with several other proteins to gain its final state.
Endoplasmic reticulum
After translation, proteins within the ER make sure that the protein is folded correctly. If after a first attempt the folding is unsuccessful, a second folding is attempted. If this fails too the protein is exported to the cytosol and labelled for destruction.
Aside from the folding, there is also a sugar chain added to the protein.
After these changes, the protein is transported to the Golgi apparatus by a coated vesicle using coating protein COPII.
Golgi apparatus
In the Golgi apparatus, the sugar chains are modified by adding or removing certain sugars.
The secretory
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https://en.wikipedia.org/wiki/Monoidal%20adjunction
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Suppose that and are two monoidal categories. A monoidal adjunction between two lax monoidal functors
and
is an adjunction between the underlying functors, such that the natural transformations
and
are monoidal natural transformations.
Lifting adjunctions to monoidal adjunctions
Suppose that
is a lax monoidal functor such that the underlying functor has a right adjoint . This adjunction lifts to a monoidal adjunction ⊣ if and only if the lax monoidal functor is strong.
See also
Every monoidal adjunction ⊣ defines a monoidal monad .
Adjoint functors
Monoidal categories
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https://en.wikipedia.org/wiki/Mongolian%20idiocy
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The obsolete medical terms Mongolian idiocy and Mongolism referred to a specific type of mental deficiency, associated with the genetic disorder now known as Down syndrome. The obsolete term for a person with this syndrome was Mongolian idiot.
In the 21st century, these terms are no longer used as medical terminology, deemed an unacceptable, offensive and misleading description of those with Down syndrome. The terminology change was brought about both by scientific and medical experts, as well as people of Asian ancestry, including those from Mongolia.
The stand-alone term "idiot" itself has a similar history of meaning and connotation change.
"Idiot" as a former technical term
While the term "idiot" is, in the present day, not used in a medical, legal or psychiatric context, instead meaning a stupid or foolish person, the term previously held meaning as a technical term used in both legal and psychiatric contexts for some type of profound intellectual disability, wherein the disabled person's mental age was considered to be two years or less. Along with terms like "moron", "imbecile", and "cretin", "idiot" has become an archaic description in legal, medical and psychiatric contexts, becoming instead an offensive term deemed outdated and discriminatory towards those it was once used to describe.
The term was gradually replaced with "profound mental retardation", which has since experienced euphemistic evolution and been gradually replaced with other terms.
History
John Langdon Down first characterized what is now known as Down syndrome as a distinguishable form of mental disability in 1862, and in a more widely published report in 1866. Due to his perception that these children shared facial similarities with the populations that German physician Johann Friedrich Blumenbach described as the "Mongolian race", Down used the term "mongoloid" in his characterisation of these patients.
The term continued its usage into the 20th century. A study published in 1908 b
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https://en.wikipedia.org/wiki/Singular%20cardinals%20hypothesis
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In set theory, the singular cardinals hypothesis (SCH) arose from the question of whether the least cardinal number for which the generalized continuum hypothesis (GCH) might fail could be a singular cardinal.
According to Mitchell (1992), the singular cardinals hypothesis is:
If κ is any singular strong limit cardinal, then 2κ = κ+.
Here, κ+ denotes the successor cardinal of κ.
Since SCH is a consequence of GCH, which is known to be consistent with ZFC, SCH is consistent with ZFC. The negation of SCH has also been shown to be consistent with ZFC, if one assumes the existence of a sufficiently large cardinal number. In fact, by results of Moti Gitik, ZFC + ¬SCH is equiconsistent with ZFC + the existence of a measurable cardinal κ of Mitchell order κ++.
Another form of the SCH is the following statement:
2cf(κ) < κ implies κcf(κ) = κ+,
where cf denotes the cofinality function. Note that κcf(κ)= 2κ for all singular strong limit cardinals κ. The second formulation of SCH is strictly stronger than the first version, since the first one only mentions strong limits. From a model in which the first version of SCH fails at ℵω and GCH holds above ℵω+2, we can construct a model in which the first version of SCH holds but the second version of SCH fails, by adding ℵω Cohen subsets to ℵn for some n.
Jack Silver proved that if κ is singular with uncountable cofinality and 2λ = λ+ for all infinite cardinals λ < κ, then 2κ = κ+. Silver's original proof used generic ultrapowers. The following important fact follows from Silver's theorem: if the singular cardinals hypothesis holds for all singular cardinals of countable cofinality, then it holds for all singular cardinals. In particular, then, if is the least counterexample to the singular cardinals hypothesis, then .
The negation of the singular cardinals hypothesis is intimately related to violating the GCH at a measurable cardinal. A well-known result of Dana Scott is that if the GCH holds below a measurable cardina
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https://en.wikipedia.org/wiki/Spinous%20cell
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Spinous cells, or prickle cells, are keratin producing epidermal cells owing their prickly appearance to their numerous intracellular connections. They make up the stratum spinosum (prickly layer) of the epidermis and provide a continuous net-like layer of protection for underlying tissue. They are susceptible to mutations caused by sunlight and can become malignant.
Location
Spinous cells are found in the superficial layers of the skin. They are found in the stratum spinosum (prickly layer, spinosum layer), which lies above the stratum basale (basal layer) and below the stratum granulosum (granular layer) of the epidermis. The spinous cells are arranged several layers thick to form a net-like covering.
Origin
Spinous cells originate through mitosis in the basal layer (also known as the germinative layer). They are pushed upward into the stratum spinosum by the continuous formation of new cells in the basal layer. They reach the outmost layer of the skin as flattened dead flaking skin cells we shed daily. The journey from origin to shed takes 25 to 45 days.
Function
Spinous cells serve “as a physical and biological barrier to the environment, preventing penetration by irritants and allergens and loss of water while maintaining internal homeostasis. They accomplish this in two ways. First, they are keratinocytes (keratin cells) whose primary function is to produce keratin, a strong structural protein. The keratin accumulates within each spinous cell as it moves upward through the epidermis layers, until the cell is almost completely filled with hardening keratin (keratinisation). Second, the cells are bound together across their cytoplasm by keratin filaments that form cell-to-cell connections (desmosomes).
Cancer
Squamous cell carcinoma (prickle cell carcinoma) is relatively common in people over age 60, with fair skin, and a history of longer term sun exposure. It is not as commonly known as other skin cancers because it is less likely to metastasize,
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https://en.wikipedia.org/wiki/Throughfall
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In hydrology, throughfall is the process which describes how wet leaves shed excess water onto the ground surface. These drops have greater erosive power because they are heavier than rain drops. Furthermore, where there is a high canopy, falling drops may reach terminal velocity, about , thus maximizing the drop's erosive potential.
Rates of throughfall are higher in areas of forest where the leaves are broad-leaved. This is because the flat leaves allow water to collect. Drip-tips also facilitate throughfall. Rates of throughfall are lower in coniferous forests as conifers can only hold individual droplets of water on their needles.
Throughfall is a crucial process when designing pesticides for foliar application since it will condition their washing and the fate of potential pollutants in the environment.
See also
Stemflow
Canopy interception
Forest floor interception
Tree shape
Notes
Hydrology
Forest ecology
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https://en.wikipedia.org/wiki/Seckel%20syndrome
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Seckel syndrome, or microcephalic primordial dwarfism (also known as bird-headed dwarfism, Harper's syndrome, Virchow–Seckel dwarfism and bird-headed dwarf of Seckel) is an extremely rare congenital nanosomic disorder. Inheritance is autosomal recessive. It is characterized by intrauterine growth restriction and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with down-slanting palpebral fissures, receding mandible and intellectual disability.
A mouse model has been developed. This mouse model is characterized by a severe deficiency of ATR protein. These mice have high levels of replicative stress and DNA damage. Adult Seckel mice display accelerated aging. These findings are consistent with the DNA damage theory of aging.
History
The syndrome was named after German-American physician Helmut Paul George Seckel (1900–1960). The synonym Harper's syndrome was named after pediatrician Rita G. Harper.
Symptoms and signs
Symptoms include:
intellectual disability (more than half of the patients have an IQ below 50)
microcephaly
sometimes pancytopenia (low blood counts)
cryptorchidism in males
low birth weight
dislocations of pelvis and elbow
unusually large eyes
blindness or visual impairment
large, low-set ears
small chin due to receded lower jaw
Genetics
It is believed to be caused by defects of genes on chromosome 3 and 18. One form of Seckel syndrome can be caused by mutation in the gene encoding the ataxia telangiectasia and Rad3-related protein () which maps to chromosome 3q22.1-q24. This gene is central in the cell's DNA damage response and repair mechanism.
Types include:
Diagnosis
Treatment
See also
Koo-Koo the Bird Girl
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https://en.wikipedia.org/wiki/Backhaul%20%28telecommunications%29
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In a hierarchical telecommunications network, the backhaul portion of the network comprises the intermediate links between the core network, or backbone network, and the small subnetworks at the edge of the network.
The most common network type in which backhaul is implemented is a mobile network. A backhaul of a mobile network, also referred to as mobile-backhaul connects a cell site towards the core network. The two main methods of mobile backhaul implementations are fiber-based backhaul and wireless point-to-point backhaul. Other methods, such as copper-based wireline, satellite communications and point-to-multipoint wireless technologies are being phased out as capacity and latency requirements become higher in 4G and 5G networks.
In both the technical and commercial definitions, backhaul generally refers to the side of the network that communicates with the global Internet, paid for at wholesale commercial access rates to or at an Internet exchange point or other core network access location. Sometimes middle mile networks exist between the customer's own LAN and those exchanges. This can be a local WAN connection.
Cell phones communicating with a single cell tower constitute a local subnetwork; the connection between the cell tower and the rest of the world begins with a backhaul link to the core of the internet service provider's network (via a point of presence). A backhaul may include wired, fiber optic and wireless components. Wireless sections may include using microwave bands and mesh and edge network topologies that may use a high-capacity wireless channel to get packets to the microwave or fiber links.
Definition
Visualizing the entire hierarchical network as a human skeleton, the core network would represent the spine, the backhaul links would be the limbs, the edge networks would be the hands and feet, and the individual links within those edge networks would be the fingers and toes.
Other examples include:
Connecting wireless base stations
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https://en.wikipedia.org/wiki/Rhodospirillum%20rubrum
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Rhodospirillum rubrum (R. rubrum) is a Gram-negative, pink-coloured bacterium, with a size of 800 to 1000 nanometers. It is a facultative anaerobe, thus capable of using oxygen for aerobic respiration under aerobic conditions, or an alternative terminal electron acceptor for anaerobic respiration under anaerobic conditions. Alternative terminal electron acceptors for R. rubrum include dimethyl sulfoxide or trimethylamine oxide.
Under aerobic growth photosynthesis is genetically suppressed and R. rubrum is then colorless. After the exhaustion of oxygen, R. rubrum immediately starts the production of photosynthesis apparatus including membrane proteins, bacteriochlorophylls and carotenoids, i.e. the bacterium becomes photosynthesis active. The repression mechanism for the photosynthesis is poorly understood. The photosynthesis of R. rubrum differs from that of plants as it possesses not chlorophyll a, but bacteriochlorophylls. While bacteriochlorophyll can absorb light up to a maximum wavelength of 800 to 925 nm, chlorophyll absorbs light having a maximum wavelength of 660 to 680 nm. R. rubrum is a spiral-shaped bacterium (spirillum, plural form: spirilla).
R. rubrum is also a nitrogen fixing bacterium, i.e., it can express and regulate nitrogenase, a protein complex that can catalyse the conversion of atmospheric dinitrogen into ammonia. When the bacteria are exposed to ammonia, darkness, and phenazine methosulfate, nitrogen fixation stops. Due to this important property, R. rubrum has been the test subject of many different groups, so as to understand the complex regulatory schemes required for this reaction to occur. It was in R. rubrum that, for the first time, post-translational regulation of nitrogenase was demonstrated. Nitrogenase is modified by an ADP-ribosylation in the arginine residue 101 (Arg101) in response to the so-called "switch-off" effectors - glutamine or ammonia - and darkness.
R. rubrum has several potential uses in biotechnology:
Quantitati
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https://en.wikipedia.org/wiki/Glue%20code
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In computer programming, glue code is executable code (often source code) that serves solely to "adapt" different parts of code that would otherwise be incompatible. Glue code does not contribute any functionality towards meeting program requirements. Instead, it often appears in code that lets existing libraries or programs interoperate, as in language bindings or foreign function interfaces such as the Java Native Interface, when mapping objects to a database using object-relational mapping, or when integrating two or more commercial off-the-shelf programs. Glue code may be written in the same language as the code it is gluing together, or in a separate glue language. Glue code is very efficient in rapid prototyping environments, where several components are quickly put together into a single language or framework.
Consequences
Because each component is independent (i.e. it is unaware of its relations and is only connected to another component through glue code), the behavior of a component and its interactions can change during the execution of the script. In addition, a different version of one of the components may behave differently, breaking the glue code.
High-level programming languages can suffer from performance penalties because glue code must run through the language interpreter, even when connecting high-performance subsystems. If performance is crucial, using configuration scripting is often preferred to directly connecting binary interfaces of components. In object-oriented scripting languages, glue code often eliminates the need for class hierarchies and large numbers of classes.
See also
Adapter pattern
Scripting language
Shell script
SWIG
Lua (programming language)
Glue logic
WinGlue
Wrapper function
Wrapper library
Method stub
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https://en.wikipedia.org/wiki/Autogenic%20succession
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"Auto-" meaning self or same, and "-genic" meaning producing or causing. Autogenic succession refers to ecological succession driven by biotic factors within an ecosystem and although the mechanisms of autogenic succession have long been debated, the role of living things in shaping the progression of succession was realized early on. Presently, there is more of a consensus that the mechanisms of facilitation, tolerance, and inhibition all contribute to autogenic succession. The concept of succession is most often associated with communities of vegetation and forests, though it is applicable to a broader range of ecosystems. In contrast, allogenic succession is driven by the abiotic components of the ecosystem.
How it occurs
The plants themselves (biotic components) cause succession to occur.
Light captured by leaves
Production of detritus
Water and nutrient uptake
Nitrogen fixation
anthropogenic climate change
These aspects lead to a gradual ecological change in a particular spot of land, known as a progression of inhabiting species. Autogenic succession can be viewed as a secondary succession because of pre-existing plant life. A 2000 case study in the journal Oecologia tested the hypothesis that areas with high plant diversity could suppress weed growth more effectively than those with lower plant diversity.
Facilitation
Improvement of site factors like increased organic matter
Inhibition
Hinders species or growth
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https://en.wikipedia.org/wiki/Allogenic%20succession
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In ecology, allogenic succession is succession driven by the abiotic components of an ecosystem. In contrast, autogenic succession is driven by the biotic components of the ecosystem. An allogenic succession can be initiated in a number of ways which can include:
Volcanic eruptions
Meteor or comet strike
Flooding
Drought
Earthquakes
Non-anthropogenic climate change
Allogenic succession can happen on a time scale that is proportionate with the disturbance. For example, allogenic succession that is the result of non-anthropogenic climate change can happen over thousands of years.
Example
The majority of Salt Marsh development comes from allogenic succession. The constant exposure to water in the intertidal zone causes the soil of a salt marsh to change over time. This results in sedimentation and nutrient buildup that also slowly raises the level of the land. What started as a sandy soil with a slightly high pH level, eventually becomes a loamy soil with a more neutral pH level. During this period, the soil-salinity will also change by starting low and eventually rising to higher levels from continued seawater exposure.
Glacier forelands are another example of ecosystems that form from autogenic but also partly allogenic succession. The importance of which is estimated to be higher in earlier successional stages, regarding rock formations, slope angles and soil composition.
See also
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https://en.wikipedia.org/wiki/Symbiotic%20bacteria
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Symbiotic bacteria are bacteria living in symbiosis with another organism or each other. For example, rhizobia living in root nodules of legumes provide nitrogen fixing activity for these plants.
Types of symbiosis
Types of symbiotic relationships are mutualism, commensalism, parasitism, and amensalism.
Endosymbiosis
Endosymbionts live inside other organisms whether that be in their bodies or cells. The theory of endosymbiosis, as known as symbiogenesis, provides an explanation for the evolution of eukaryotic organisms. According to the theory of endosymbiosis for the origin of eukaryotic cells, scientists believe that eukaryotes originated from the relationship between two or more prokaryotic cells approximately 2.7 billion years ago. It is suggested that specifically ancestors of mitochondria and chloroplasts entered into an endosymbiotic relationship with another prokaryotic cell, eventually evolving into the eukaryotic cells that people are familiar with today.
Ectosymbiosis
Ectosymbiosis is defined as a symbiotic relationship in which one organism lives on the outside surface of a different organism. For instance, barnacles on whales is an example of an ectosymbiotic relationship where the whale provides the barnacle with a home, a ride, and access to food. The whale is not harmed, but it also does not receive any benefits so this is also an example of commensalism. An example of ectosymbiotic bacteria is cutibacterium acnes. These bacteria are involved in a symbiotic relationship with humans on whose skin they live. Cutibacterium acnes can cause acne when the skin becomes too oily, but they also reduce the skin's susceptibility to skin diseases caused by oxidative stress.
Symbiotic relationships
Certain plants establish a symbiotic relationship with bacteria, enabling them to produce nodules that facilitate the conversion of atmospheric nitrogen to ammonia. In this connection, cytokinins have been found to play a role in the development of root fixing n
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https://en.wikipedia.org/wiki/Derived%20unique%20key%20per%20transaction
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In cryptography, Derived Unique Key Per Transaction (DUKPT) is a key management scheme in which for every transaction, a unique key is used which is derived from a fixed key. Therefore, if a derived key is compromised, future and past transaction data are still protected since the next or prior keys cannot be determined easily. DUKPT is specified in ANSI X9.24 part 1.
Overview
DUKPT allows the processing of the encryption to be moved away from the devices that hold the shared secret. The encryption is done with a derived key, which is not re-used after the transaction. DUKPT is used to encrypt electronic commerce transactions. While it can be used to protect information between two companies or banks, it is typically used to encrypt PIN information acquired by Point-Of-Sale (POS) devices.
DUKPT is not itself an encryption standard; rather it is a key management technique. The features of the DUKPT scheme are:
enable both originating and receiving parties to be in agreement as to the key being used for a given transaction,
each transaction will have a distinct key from all other transactions, except by coincidence,
if a present derived key is compromised, past and future keys (and thus the transactional data encrypted under them) remain uncompromised,
each device generates a different key sequence,
originators and receivers of encrypted messages do not have to perform an interactive key-agreement protocol beforehand.
History
DUKPT was invented in the late 1980s at Visa but didn’t receive much acceptance until the 1990s, when industry practices shifted towards recommending, and later requiring, that each device have a distinct encryption key.
Before DUKPT, state of the art was known as Master/Session, which required every PIN-encrypting device to be initialized with a unique master key. In handling transactions originating from devices using Master/Session key management, an unwanted side effect was the need for a table of encryption keys as numerous
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https://en.wikipedia.org/wiki/Buchanan%20Medal
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The Buchanan Medal is awarded by the Royal Society "in recognition of distinguished contribution to the medical sciences generally". The award was created in 1897 from a fund to the memory of London physician Sir George Buchanan (1831–1895). It was to be awarded once every five years, but since 1990 the medal has been awarded every two years.
Since its creation, it has been awarded 28 times, and unlike other Royal Society medals such as the Royal Medal, it has never been awarded to the same individual multiple times. As a result of the criteria for the medal, most of the winners have been doctors or other medical professionals; an exception was Frederick Warner, an engineer who won the medal in 1982 "for his important role in reducing pollution of the River Thames and of his significant contributions to risk assessment".
Two winners have also won a Nobel Prize. The first, Barry Marshall, who was awarded the Buchanan Medal in 1998 "in recognition of his work on discovering the role of Helicobacter pylori as a cause of diseases such as duodenal ulcer, gastric ulcer, gastric cancer and gastritis-associated dyspepsia" and won the Nobel Prize in Physiology or Medicine in 2005. The second, Peter Ratcliffe, won the medal in 2017 "for his ground-breaking research on oxygen sensing and signalling pathways mediating cellular responses to hypoxia", and was awarded the Nobel Prize in 2019.
The first winner of the Buchanan Medal was John Simon, who won his medal in 1897 "for his distinguished services as an organizer of medical sanitary administration in this country, and as a promoter of scientific research relating to public health".
List of recipients
Source: Royal Society
See also
List of medicine awards
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https://en.wikipedia.org/wiki/Center%20for%20Biologics%20Evaluation%20and%20Research
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The Center for Biologics Evaluation and Research (CBER) is one of six main centers for the U.S. Food and Drug Administration (FDA), which is a part of the U.S. Department of Health and Human Services. The current Director of CBER is Peter Marks, M.D., PhD. CBER is responsible for assuring the safety, purity, potency, and effectiveness of biologics and related products (such as vaccines, live biotherapeutics (probiotics), blood products, and cell, tissue, and gene therapies). Not all biologics are regulated by CBER. Monoclonal antibodies and other therapeutic proteins are regulated by the FDA Center for Drug Evaluation and Research (CDER).
Scope
Blood for transfusion and as a raw material for drug products, as well as reagents used for blood typing and other related activities -and- plasma derivatives, including immunoglobulins, hyperimmune products, and antitoxins.
Blood and blood products activities are managed through the Office of Blood Research and Review (OBRR)
Human cells, tissues, and cellular and tissue-based products (HCT/Ps), except vascularized organs for transplantation and the associated blood vessels.
Vaccines for use in humans.
Diagnostic and therapeutic allergenic extracts.
Live biotherapeutics (probiotics).
Some medical devices, specifically test kits for HIV, tests used to screen blood donations, blood bank collection machines and equipment, and blood bank computer software.
Xenotransplantation
Historically, CBER was responsible for some therapeutic proteins, such as monoclonal antibodies. Control of these has been transferred to CDER. Some other drugs, such as certain anticoagulants and plasma volume expanders remain under the control of CBER.
Authority
As of July 2006 CBER's authority resides in sections 351 and 361 of the Public Health Service Act and in various sections of the Food, Drug and Cosmetic Act.
Section 351 of the Public Health Service Act requires licensure of biological products that travel in interstate commerce in the
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https://en.wikipedia.org/wiki/Aprotinin
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The drug aprotinin (Trasylol, previously Bayer and now Nordic Group pharmaceuticals), is a small protein bovine pancreatic trypsin inhibitor (BPTI), or basic trypsin inhibitor of bovine pancreas, which is an antifibrinolytic molecule that inhibits trypsin and related proteolytic enzymes. Under the trade name Trasylol, aprotinin was used as a medication administered by injection to reduce bleeding during complex surgery, such as heart and liver surgery. Its main effect is the slowing down of fibrinolysis, the process that leads to the breakdown of blood clots. The aim in its use was to decrease the need for blood transfusions during surgery, as well as end-organ damage due to hypotension (low blood pressure) as a result of marked blood loss. The drug was temporarily withdrawn worldwide in 2007 after studies suggested that its use increased the risk of complications or death; this was confirmed by follow-up studies. Trasylol sales were suspended in May 2008, except for very restricted research use. In February 2012 the European Medicines Agency (EMA) scientific committee reverted its previous standpoint regarding aprotinin, and has recommended that the suspension be lifted. Nordic became distributor of aprotinin in 2012.
Chemistry
Aprotinin is a monomeric (single-chain) globular polypeptide derived from bovine lung tissue. It has a molecular weight of 6512 Da and consists of 16 different amino acid types arranged in a chain 58 residues long that folds into a stable, compact tertiary structure of the 'small SS-rich" type, containing 3 disulfides, a twisted β-hairpin and a C-terminal α-helix.
The amino acid sequence for bovine BPTI is RPDFC LEPPY TGPCK ARIIR YFYNA KAGLC QTFVY GGCRA KRNNF KSAED CMRTC GGA. There are 10 positively charged lysine (K) and arginine (R) side chains and only 4 negative aspartate (D) and glutamates (E), making the protein strongly basic, which accounts for the basic in its name. (Because of the usual source organism, BPTI is sometimes refer
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https://en.wikipedia.org/wiki/Srm%20%28Unix%29
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srm (or Secure Remove) is a command line utility for Unix-like computer systems for secure file deletion. srm removes each specified file by overwriting, renaming, and truncating it before unlinking. This prevents other people from undeleting or recovering any information about the file from the command line.
Platform-specific behaviours and bugs
Filesystems with hard links
Attempting to secure delete a file with multiple hard links results in a warning from srm stating that the current access path has been unlinked, but the data itself was not overwritten or truncated. This is an undocumented feature of srm 1.2.8 on Mac OS X 10.9, and is erroneously documented in 1.2.11 as a behaviour activated by the OpenBSD rm-compatible option -P. However, in both the OS X and SourceForge srm implementations, the behaviour of unlinking but not overwriting multi-linked files is always active, as long as the platform reports hard links.
srm 1.2.8 on Mac OS X 10.9 has a -n option, which means "overwrite file, but do not rename or unlink it." However, if the file has multiple links, the multiple-link file data protection feature activates first, removing the file, even though the -n option specifies "do not rename or unlink the file". The -n option has been removed from the code and manual of srm version 1.2.11, the latest SourceForge.net version. As a consequence, this option/feature conflict does not occur.
OS X
A number of file systems support file forks (called resource forks and named forks on OS X (particularly HFS+), and alternate data streams on NTFS), or extended attributes. However, OS X is the only platform on which srm securely deletes any of this additional data in files.
On OS X, only the most common non-data fork, the resource fork, is handled in this way. This support was included in Apple’s 1.2.8 and SourceForge's 1.2.9.
srm was removed from OS X/macOS in v10.11 El Capitan, as part of the removal of the "Secure Empty Trash" feature for security reasons.
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https://en.wikipedia.org/wiki/Calix%2C%20Inc.
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Calix, Inc. is a telecommunications company that specializes in providing software platforms, systems, and services to support the delivery of broadband services. The company was founded in 1999 and is headquartered in San Jose, California.
Calix provides cloud, software platforms, systems and services to communications service providers.
Calix maintains facilities in Petaluma, CA, Minneapolis, MN, San Jose, CA, Richardson, TX in the USA and facilities in Nanjing, China and Bangalore, India..
Customers
Calix customers include SCTelcom, Verizon, ALLO Communications, CityFibre, Nex-Tech, Gibson Connect, ITS Fiber, Sogetel, and over 1,600 other broadband service providers globally, majority being in North America.
Competitors
Calix competitors include Cisco, Adtran, Nokia, Allied Telesis, Huawei, Tellabs, ZTE and DZS.
Industry News
With Amazon Alexa, Calix Translates Smart Home Opp Into Reality
Amazon expands white-box Alexa device lineup with new home hub and gateway hardware
How Verizon & Calix Unlocked NGPON2
Acquisitions history
In 2006, Calix purchased Optical Solutions, Inc., based in Minneapolis, MN.
In 2010, Calix announced acquisition of one-time rival Occam Networks, Inc., based in Santa Barbara, California. The acquisition was completed in February, 2011.
In Nov 2012, Calix completed acquisition of Ericsson’s fiber access assets.
Other Resources
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https://en.wikipedia.org/wiki/Pseudoautosomal%20region
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The pseudoautosomal regions, PAR1, PAR2, are homologous sequences of nucleotides on the X and Y chromosomes.
The pseudoautosomal regions get their name because any genes within them (so far at least 29 have been found for humans) are inherited just like any autosomal genes. PAR1 comprises 2.6 Mbp of the short-arm tips of both X and Y chromosomes in humans and great apes (X and Y are 154 Mbp and 62 Mbp in total). PAR2 is at the tips of the long arms, spanning 320 kbp.
Location
The locations of the PARs within GRCh38 are:
The locations of the PARs within GRCh37 are:
Inheritance and function
Normal male mammals have two copies of these genes: one in the pseudoautosomal region of their Y chromosome, the other in the corresponding portion of their X chromosome. Normal females also possess two copies of pseudoautosomal genes, as each of their two X chromosomes contains a pseudoautosomal region. Crossing over between the X and Y chromosomes is normally restricted to the pseudoautosomal regions; thus, pseudoautosomal genes exhibit an autosomal, rather than sex-linked, pattern of inheritance. So, females can inherit an allele originally present on the Y chromosome of their father.
The function of these pseudoautosomal regions is that they allow the X and Y chromosomes to pair and properly segregate during meiosis in males.
Genes
Pseudoautosomal genes are found in two different locations: PAR1 and PAR2. These are believed to have evolved independently.
PAR1
pseudoautosomal PAR1
AKAP17A
ASMT
ASMTL
CD99
CRLF2
CSF2RA
DHRSX
GTPBP6
IL3RA
P2RY8
PLCXD1
PPP2R3B
SHOX
SLC25A6
XG, which straddles the PAR1 region boundary
ZBED1
in mice, some PAR1 genes have transferred to autosomes.
PAR2
pseudoautosomal PAR2
IL9R
SPRY3
VAMP7, also known as SYBL1
CXYorf1, also known as FAM39A and now mapped to the pseudogene WASH6P, but of interest due to its proximity to the telomere.
Pathology
Pairing (synapsis) of the X and Y chromosomes and crossing over (recombinat
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https://en.wikipedia.org/wiki/Artificial%20cell
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An artificial cell, synthetic cell or minimal cell is an engineered particle that mimics one or many functions of a biological cell. Often, artificial cells are biological or polymeric membranes which enclose biologically active materials. As such, liposomes, polymersomes, nanoparticles, microcapsules and a number of other particles can qualify as artificial cells.
The terms "artificial cell" and "synthetic cell" are used in a variety of different fields and can have different meanings, as it is also reflected in the different sections of this article. Some stricter definitions are based on the assumption that the term "cell" directly relates to biological cells and that these structures therefore have to be alive (or part of a living organism) and, further, that the term "artificial" implies that these structures are artificially built from the bottom-up, i.e. from basic components. As such, in the area of synthetic biology, an artificial cell can be understood as a completely synthetically made cell that can capture energy, maintain ion gradients, contain macromolecules as well as store information and have the ability to replicate. This kind of artificial cell has not yet been made.
However, in other cases, the term "artificial" does not imply that the entire structure is man-made, but instead, it can refer to the idea that certain functions or structures of biological cells can be modified, simplified, replaced or supplemented with a synthetic entity.
In other fields, the term "artificial cell" can refer to any compartment that somewhat resembles a biological cell in size or structure, but is synthetically made, or even fully made from non-biological components. The term "artificial cell" is also used for structures with direct applications such as compartments for drug delivery. Micro-encapsulation allows for metabolism within the membrane, exchange of small molecules and prevention of passage of large substances across it. The main advantages of encapsulati
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https://en.wikipedia.org/wiki/Small%20nuclear%20RNA
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Small nuclear RNA (snRNA) is a class of small RNA molecules that are found within the splicing speckles and Cajal bodies of the cell nucleus in eukaryotic cells. The length of an average snRNA is approximately 150 nucleotides. They are transcribed by either RNA polymerase II or RNA polymerase III. Their primary function is in the processing of pre-messenger RNA (hnRNA) in the nucleus. They have also been shown to aid in the regulation of transcription factors (7SK RNA) or RNA polymerase II (B2 RNA), and maintaining the telomeres.
snRNA are always associated with a set of specific proteins, and the complexes are referred to as small nuclear ribonucleoproteins (snRNP, often pronounced "snurps"). Each snRNP particle is composed of a snRNA component and several snRNP-specific proteins (including Sm proteins, a family of nuclear proteins). The most common human snRNA components of these complexes are known, respectively, as: U1 spliceosomal RNA, U2 spliceosomal RNA, U4 spliceosomal RNA, U5 spliceosomal RNA, and U6 spliceosomal RNA. Their nomenclature derives from their high uridine content.
snRNAs were discovered by accident during a gel electrophoresis experiment in 1966. An unexpected type of RNA was found in the gel and investigated. Later analysis has shown that these RNA were high in uridylate and were established in the nucleus.
snRNAs and small nucleolar RNAs (snoRNAs) are not the same and neither is a subtype of the other. Both are different and are a class under small RNAs. These are small RNA molecules that play an essential role in RNA biogenesis and guide chemical modifications of ribosomal RNAs (rRNAs) and other RNA genes (tRNA and snRNAs). They are located in the nucleolus and the Cajal bodies of eukaryotic cells (the major sites of RNA synthesis), where they are called scaRNAs (small Cajal body-specific RNAs).
Classes
snRNA are often divided into two classes based upon both common sequence features as well as associated protein factors such as the R
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https://en.wikipedia.org/wiki/Postal%20Alpha%20Numeric%20Encoding%20Technique
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The Postal Alpha Numeric Encoding Technique (PLANET) barcode was used by the United States Postal Service to identify and track pieces of mail during delivery - the Post Office's "CONFIRM" services. It was fully superseded by Intelligent Mail Barcode by January 28, 2013.
Barcode
A PLANET barcode appears either 12 or 14 digits long. The barcode:
identifies mailpiece class and shape
identifies the Confirm Subscriber ID
includes up to 6 digits of additional information that the Confirm subscriber chose, such as a mailing number, mailing campaign ID or customer ID
ends with a check digit
Encoding
Like POSTNET, PLANET encodes the data in half- and full-height bars. Also like POSTNET, PLANET always starts and ends with a full bar (often called a guard rail), and each individual digit is represented by a set of five bars using a two-out-of-five code. However, in POSTNET, the two bars are full bars; in PLANET, the two-of-five are the short bars. As with POSTNET, the check digit is calculated by summing the other characters and calculating the single digit which, when added to the sum, makes the total divisible by 10.
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https://en.wikipedia.org/wiki/Perplexity
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In information theory, perplexity is a measurement of how well a probability distribution or probability model predicts a sample. It may be used to compare probability models. A low perplexity indicates the probability distribution is good at predicting the sample. Perplexity was originally introduced in 1977 in the context of speech recognition by Frederick Jelinek, Robert Leroy Mercer, Lalit R. Bahl, and James K. Baker.
Perplexity of a Probability Distribution
The perplexity PP of a discrete probability distribution p is a concept widely used in information theory, machine learning, and statistical modeling. It is defined as
where H(p) is the entropy (in bits) of the distribution, and x ranges over the events. The base of the logarithm need not be 2: The perplexity is independent of the base, provided that the entropy and the exponentiation use the same base. In some contexts, this measure is also referred to as the (order-1 true) diversity.
Perplexity of a random variable X may be defined as the perplexity of the distribution over its possible values x. It can be thought of as a measure of uncertainty or "surprise" related to the outcomes.
In the special case where p models a fair k-sided die (a uniform distribution over k discrete events), its perplexity is k. A random variable with perplexity k has the same uncertainty as a fair k-sided die. One is said to be "k-ways perplexed" about the value of the random variable. Unless it is a fair k-sided die, more than k values may be possible, but the overall uncertainty is not greater because some values may have a probability greater than 1/k.
Perplexity is sometimes used as a measure of the difficulty of a prediction problem. However, it's not always an accurate representation. For example, if you have two choices, one with probability 0.9, your chances of a correct guess using the optimal strategy are 90 percent. Yet, the perplexity is 2−0.9 log2 0.9 - 0.1 log2 0.1= 1.38. The inverse of the perplexity, 1/1.38
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https://en.wikipedia.org/wiki/David%20George%20Kendall
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David George Kendall FRS (15 January 1918 – 23 October 2007) was an English statistician and mathematician, known for his work on probability, statistical shape analysis, ley lines and queueing theory. He spent most of his academic life in the University of Oxford (1946–1962) and the University of Cambridge (1962–1985). He worked with M. S. Bartlett during World War II, and visited Princeton University after the war.
Life and career
David George Kendall was born on 15 January 1918 in Ripon, West Riding of Yorkshire, and attended Ripon Grammar School before attending Queen's College, Oxford, graduating in 1939.
He worked on rocketry at the Ministry of Supply's Projectile Development Establishment during the World War II, before moving to Magdalen College, Oxford, in 1946.
In 1962 he was appointed the first Professor of Mathematical Statistics in the Statistical Laboratory, University of Cambridge; in which post he remained until his retirement in 1985. He was elected to a professorial fellowship at Churchill College, and he was a founding trustee of the Rollo Davidson Trust. In 1986, he was awarded an Honorary Degree (Doctor of Science) by the University of Bath.
Kendall was an expert in probability and data analysis, and pioneered statistical shape analysis including the study of ley lines. He defined Kendall's notation for queueing theory.
The Royal Statistical Society awarded him the Guy Medal in Silver in 1955, followed in 1981 by the Guy Medal in Gold. In 1980 the London Mathematical Society awarded Kendall their Senior Whitehead Prize, and in 1989 their De Morgan Medal. He was elected a fellow of the Royal Society in 1964.
Kendall also played a key role in founding the Bernoulli Society in 1975, and was its initial president.
He was married to Diana Fletcher from 1952 until his death. They had two sons and four daughters, including Wilfrid Kendall, professor in the Department of Statistics at the University of Warwick, journalist Bridget Kendall MBE, Feli
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https://en.wikipedia.org/wiki/Multitape%20Turing%20machine
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A multi-tape Turing machine is a variant of the Turing machine that utilizes several tapes. Each tape has its own head for reading and writing. Initially, the input appears on tape 1, and the others start out blank.
This model intuitively seems much more powerful than the single-tape model, but any multi-tape machine—no matter how many tapes—can be simulated by a single-tape machine using only quadratically more computation time. Thus, multi-tape machines cannot calculate any more functions than single-tape machines, and none of the robust complexity classes (such as polynomial time) are affected by a change between single-tape and multi-tape machines.
Formal definition
-tape Turing machine can be formally defined as a 7-tuple , following the notation of a Turing machine:
is a finite, non-empty set of tape alphabet symbols;
is the blank symbol (the only symbol allowed to occur on the tape infinitely often at any step during the computation);
is the set of input symbols, that is, the set of symbols allowed to appear in the initial tape contents;
is a finite, non-empty set of states;
is the initial state;
is the set of final states or accepting states. The initial tape contents is said to be accepted by if it eventually halts in a state from .
is a partial function called the transition function, where L is left shift, R is right shift.
A -tape Turing machine computes as follows. Initially, receives its input on the leftmost positions of the first tape, the rest of the first tape as well as other tapes is blank (i.e., filled with blank symbols). All the heads start on the leftmost position of the tapes. Once has started, the computation proceeds according to the rules described by the transition function. The computation continues until it enters the accept states, at which point it halts.
Two-stack Turing machine
Two-stack Turing machines have a read-only input and two storage tapes. If a head moves left on either tape a blank is printed on
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https://en.wikipedia.org/wiki/Mastoid%20canaliculus
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In the lateral part of the jugular fossa of the temporal bone is the mastoid canaliculus for the entrance of the auricular branch of the vagus nerve.
Additional images
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https://en.wikipedia.org/wiki/Wireless%20Toronto
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Wireless Toronto is a volunteer not-for-profit community wireless network in Toronto. Wireless Toronto began in 2005 with the goal of setting up no-cost public wireless Internet access around the Greater Toronto Area and exploring ways to use Wi-Fi technology to strengthen local community and culture. At its peak, Wireless Toronto hotspots served over 1000 connections per day at 38 individual locations.
Wireless Toronto hotspots are created using Linksys WRT54G or Motorola WR850G wireless routers running OpenWrt and WifiDog.
Other free wireless services in the GTA
The Toronto Public Library (TPL) offers free public wireless access in all of its 99 branches.
The Markham Public Libraries (MPL) offers free public wireless access in the Angus Glen Library, the Markham Village Library, the Thornhill Community Library, and the Unionville Library
Viva offers free wireless access on its Rapid Transit Vehicles
TOwifi offers a free Wi-Fi hotspot map
The TTC offers free, ad supported wireless service at many of its stations
See also
Municipal wireless network
List of wireless community networks by region
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https://en.wikipedia.org/wiki/Bombieri%E2%80%93Vinogradov%20theorem
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In mathematics, the Bombieri–Vinogradov theorem (sometimes simply called Bombieri's theorem) is a major result of analytic number theory, obtained in the mid-1960s, concerning the distribution of primes in arithmetic progressions, averaged over a range of moduli. The first result of this kind was obtained by Mark Barban in 1961 and the Bombieri–Vinogradov theorem is a refinement of Barban's result. The Bombieri–Vinogradov theorem is named after Enrico Bombieri and A. I. Vinogradov, who published on a related topic, the density hypothesis, in 1965.
This result is a major application of the large sieve method, which developed rapidly in the early 1960s, from its beginnings in work of Yuri Linnik two decades earlier. Besides Bombieri, Klaus Roth was working in this area. In the late 1960s and early 1970s, many of the key ingredients and estimates were simplified by Patrick X. Gallagher.
Statement of the Bombieri–Vinogradov theorem
Let and be any two positive real numbers with
Then
Here is the Euler totient function, which is the number of summands for the modulus q, and
where denotes the von Mangoldt function.
A verbal description of this result is that it addresses the error term in the prime number theorem for arithmetic progressions, averaged over the moduli q up to Q. For a certain range of Q, which are around if we neglect logarithmic factors, the error averaged is nearly as small as . This is not obvious, and without the averaging is about of the strength of the Generalized Riemann Hypothesis (GRH).
See also
Elliott–Halberstam conjecture (a generalization of Bombieri–Vinogradov)
Vinogradov's theorem (named after Ivan Matveyevich Vinogradov)
Notes
External links
The Bombieri-Vinogradov Theorem, R.C. Vaughan's Lecture note.
Sieve theory
Theorems in analytic number theory
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https://en.wikipedia.org/wiki/Submandibular%20ganglion
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The submandibular ganglion (or submaxillary ganglion in older texts) is part of the human autonomic nervous system. It is one of four parasympathetic ganglia of the head and neck. (The others are the otic ganglion, pterygopalatine ganglion, and ciliary ganglion).
Location and relations
The submandibular ganglion is small and fusiform in shape. It is situated above the deep portion of the submandibular gland, on the hyoglossus muscle, near the posterior border of the mylohyoid muscle.
The ganglion 'hangs' by two nerve filaments from the lower border of the lingual nerve (itself a branch of the mandibular nerve, CN V3). It is suspended from the lingual nerve by two filaments, one anterior and one posterior. Through the posterior of these it receives a branch from the chorda tympani nerve which runs in the sheath of the lingual nerve.
Fibers
Like other parasympathetic ganglia of the head and neck, the submandibular ganglion is the site of synapse for parasympathetic fibers and carries other types of nerve fiber that do not synapse in the ganglion. In summary, the fibers carried in the ganglion are:
Sympathetic fibers from the external carotid plexus, via the facial nerve and its branches. These do not synapse in this ganglion.
Preganglionic parasympathetic fibers from the superior salivatory nucleus of the Pons, via the chorda tympani and lingual nerve, which synapse at this ganglion.
Postganglionic parasympathetic fibers to the oral mucosa and the submandibular and sublingual salivary glands. They are secretomotor to these glands. Some of the postganglionic fibers reach the sublingual gland after they re-enter the lingual nerve.
Additional images
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https://en.wikipedia.org/wiki/Middle%20cranial%20fossa
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The middle cranial fossa is formed by the sphenoid bones, and the temporal bones. It lodges the temporal lobes, and the pituitary gland. It is deeper than the anterior cranial fossa, is narrow medially and widens laterally to the sides of the skull. It is separated from the posterior cranial fossa by the clivus and the petrous crest.
It is bounded in front by the posterior margins of the lesser wings of the sphenoid bone, the anterior clinoid processes, and the ridge forming the anterior margin of the chiasmatic groove; behind, by the superior angles of the petrous portions of the temporal bones and the dorsum sellae; laterally by the temporal squamae, sphenoidal angles of the parietals, and greater wings of the sphenoid. It is traversed by the squamosal, sphenoparietal, sphenosquamosal, and sphenopetrosal sutures.
Anatomy
Features
Middle part
The middle part of the fossa presents, in front, the chiasmatic groove and tuberculum sellae; the chiasmatic groove ends on either side at the optic foramen, which transmits the optic nerve and ophthalmic artery to the orbital cavity.
Behind the optic foramen the anterior clinoid process is directed backward and medialward and gives attachment to the cerebellar tentorium .
Behind the tuberculum sellae is a deep depression, the sella turcica, containing the fossa hypophyseos, which lodges the pituitary gland, and presents on its anterior wall the middle clinoid processes.
The sella turcica is bounded posteriorly by a quadrilateral plate of bone, the dorsum sellae, the upper angles of which are surmounted by the posterior clinoid processes: these afford attachment to the cerebellar tentorium, and below each is a notch for the abducent nerve.
On either side of the sella turcica is the carotid groove, which is broad, shallow, and curved somewhat like the italic letter f.
It begins behind at the foramen lacerum, and ends on the medial side of the anterior clinoid process, where it is sometimes converted into a foramen (ca
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https://en.wikipedia.org/wiki/Anterior%20cranial%20fossa
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The anterior cranial fossa is a depression in the floor of the cranial base which houses the projecting frontal lobes of the brain. It is formed by the orbital plates of the frontal, the cribriform plate of the ethmoid, and the small wings and front part of the body of the sphenoid; it is limited behind by the posterior borders of the small wings of the sphenoid and by the anterior margin of the chiasmatic groove. The lesser wings of the sphenoid separate the anterior and middle fossae.
Structure
It is traversed by the frontoethmoidal, sphenoethmoidal, and sphenofrontal sutures.
Its lateral portions roof in the orbital cavities and support the frontal lobes of the cerebrum; they are convex and marked by depressions for the brain convolutions, and grooves for branches of the meningeal vessels.
The central portion corresponds with the roof of the nasal cavity, and is markedly depressed on either side of the crista galli.
It presents, in and near the median line, from before backward, the commencement of the frontal crest for the attachment of the falx cerebri; the foramen cecum, between the frontal bone and the crista galli of the ethmoid, which usually transmits a small vein from the nasal cavity to the superior sagittal sinus; behind the foramen cecum, the crista galli, the free margin of which affords attachment to the falx cerebri; on either side of the crista galli, the olfactory groove formed by the cribriform plate, which supports the olfactory bulb and presents foramina for the transmission of the olfactory nerves, and in front a slit-like opening for the nasociliary nerve.
Lateral to either olfactory groove are the internal openings of the anterior and posterior ethmoidal foramina; the anterior, situated about the middle of the lateral margin of the olfactory groove, transmits the anterior ethmoidal vessels and the nasociliary nerve; the nerve runs in a groove along the lateral edge of the cribriform plate to the slit-like opening above mentioned; the p
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https://en.wikipedia.org/wiki/Deep%20branch%20of%20radial%20nerve
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The radial nerve divides into a superficial (sensory) and deep (motor) branch at the cubital fossa. The deep branch of the radial nerve winds to the back of the forearm around the lateral side of the radius between the two planes of fibers of the Supinator, and is prolonged downward between the superficial and deep layers of muscles, to the middle of the forearm. The deep branch provides motor function to the muscles in the posterior compartment of the forearm, which is mostly the extensor muscles of the hand.
The radial nerve arises from the posterior cord of the brachial plexus. The posterior cord takes nerves from the upper, lower, and middle trunk, so ultimately the radial nerve is formed from the anterior rami of C5 through T1.
The radial nerve passes through the axilla, which makes it susceptible to injury. It can be compressed against the humerus by crutches, causing crutch paralysis. Symptoms of damage to the deep branch of the radial nerve typically include "wrist drop", which is the flexion of fingers, hand, and wrist, since the extensor muscles supplied by the nerve are paralyzed. Normal sensation of the skin is retained, since this nerve only provides sensory function to ligaments and articulations of the carpal and metacarpal joints.
Since the nerve passes dorsally around the head of the radius, it is susceptible to traction or compression injuries when the elbow joint is injured, in particular, radial dislocation. Another area of potential entrapment is the arcade of Frohse, a fibrous arch formed from the proximal part of the superficial head of the supinator, under which the deep branch of the radial nerve passes. The passage for the nerve varies in size. In some cases of spontaneous paralysis of the nerve, releasing this fibrous band released pressure on the nerve and restored function
Considerably diminished in size, it descends as the posterior interosseous nerve.
For some authors, the deep branch of the radial nerve is the same as the poster
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https://en.wikipedia.org/wiki/Superficial%20branch%20of%20radial%20nerve
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The superficial branch of the radial nerve passes along the front of the radial side of the forearm to the commencement of its lower third. It is a sensory nerve.
It lies at first slightly lateral to the radial artery, concealed beneath the Brachioradialis. In the middle third of the forearm, it lies behind the same muscle, close to the lateral side of the artery.
It quits the artery about 7 cm. above the wrist, passes beneath the tendon of the Brachioradialis, and, piercing the deep fascia, divides into two branches: lateral and medial.
Structure
Lateral branch
The lateral branch, the smaller, supplies the radial side of the thumb (by a digital nerve), the skin of the radial side and ball of the thumb, joining with the volar branch of the lateral antebrachial cutaneous nerve.
Medial branch
The medial branch communicates, above the wrist, with the dorsal branch of the lateral antebrachial cutaneous, and, on the back of the hand, with the dorsal branch of the ulnar nerve.
It then divides into four digital nerves, which are distributed as follows: the first supplies the ulnar side of the thumb; the second, the radial side of the index finger; the third, the adjoining sides of the index and middle fingers; the fourth communicates with a filament from the dorsal branch of the ulnar nerve, and supplies the adjacent sides of the middle and ring fingers.
Clinical significance
The superficial branch of radial nerve is associated with an entrapment neuropathy called Wartenberg's syndrome. The nerve may be compressed due to wearing a tight wristband, watch or bracelet.
Additional images
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https://en.wikipedia.org/wiki/Muscular%20branches%20of%20the%20radial%20nerve
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The muscular branches of the radial nerve supply the Triceps brachii, Anconæus, Brachioradialis, and Extensor carpi radialis longus, and are grouped as medial, posterior, and lateral.
Medial
The medial muscular branches supply the medial head of the Triceps brachii.
That to the medial head is a long, slender filament, which lies close to the ulnar nerve as far as the lower third of the arm, and is therefore frequently spoken of as the ulnar collateral nerve.
Posterior
The posterior muscular branch, of large size, arises from the nerve in the groove between the Triceps brachii and the humerus.
It divides into filaments, which supply the medial and lateral heads of the Triceps brachii and the Anconæus muscles.
The branch for the latter muscle is a long, slender filament, which descends in the substance of the medial head of the Triceps brachii.
Lateral
The lateral muscular branches supply the Brachioradialis, Extensor carpi radialis longus, and the lateral part of the Brachialis.
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https://en.wikipedia.org/wiki/Guard%20byte
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A guard byte is a part of a computer program's memory that helps software developers find buffer overflows while developing the program.
Principle
When a program is compiled for debugging, all memory allocations are prefixed and postfixed by guard bytes. Special memory allocation routines may then perform additional tasks to determine unwanted read and write attempts outside the allocated memory. These extra bytes help to detect that the program is writing into (or even reading from) inappropriate memory areas, potentially causing buffer overflows. In case of accessing these bytes by the program's algorithm, the programmer is warned with information assisting him/her to locate the problem.
Checking for the inappropriate access to the guard bytes may be done in two ways:
by setting a memory breakpoint on a condition of write and/or read to those bytes, or
by pre-initializing the guard bytes with specific values and checking the values upon deallocation.
The first way is possible only with a debugger that handles such breakpoints, but significantly increases the chance of locating the problem. The second way does not require any debuggers or special environments and can be done even on other computers, but the programmer is alerted about the overflow only upon the deallocation, which is sometimes quite late.
Because guard bytes require additional code to be executed and additional memory to be allocated, they are used only when the program is compiled for debugging. When compiled as a release, guard bytes are not used at all, neither the routines working with them.
Example
A programmer wants to allocate a buffer of 100 bytes of memory while debugging. The system memory allocating routine will allocate 108 bytes instead, adding 4 leading and 4 trailing guard bytes, and return a pointer shifted by the 4 leading guard bytes to the right, hiding them from the programmer. The programmer should then work with the received pointer without the knowledge of the presence
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https://en.wikipedia.org/wiki/Ultra%20Port%20Architecture
|
The Ultra Port Architecture (UPA) bus was developed by Sun Microsystems as a high-speed graphics card to CPU interconnect, beginning with the Ultra 1 workstation in 1995.
See also
List of device bandwidths
External links
UPA Bus Whitepaper
Computer buses
Sun Microsystems hardware
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https://en.wikipedia.org/wiki/Exec%20%28system%20call%29
|
In computing, exec is a functionality of an operating system that runs an executable file in the context of an already existing process, replacing the previous executable. This act is also referred to as an overlay. It is especially important in Unix-like systems, although it exists elsewhere. As no new process is created, the process identifier (PID) does not change, but the machine code, data, heap, and stack of the process are replaced by those of the new program.
The exec call is available for many programming languages including compilable languages and some scripting languages. In OS command interpreters, the built-in command replaces the shell process with the specified program.
Nomenclature
Interfaces to exec and its implementations vary. Depending on programming language it may be accessible via one or more functions, and depending on operating system it may be represented with one or more actual system calls. For this reason exec is sometimes described as a collection of functions.
Standard names of such functions in C are , , , , , and (see below), but not "exec" itself. The Linux kernel has one corresponding system call named "execve", whereas all aforementioned functions are user-space wrappers around it.
Higher-level languages usually provide one call named .
Unix, POSIX, and other multitasking systems
C language prototypes
The POSIX standard declares exec functions in the header file, in the C language. The same functions are declared in for DOS (see below), OS/2, and Microsoft Windows.
int execl(char const *path, char const *arg0, ...);
int execle(char const *path, char const *arg0, ..., char const *envp[]);
int execlp(char const *file, char const *arg0, ...);
int execv(char const *path, char const *argv[]);
int execve(char const *path, char const *argv[], char const *envp[]);
int execvp(char const *file, char const *argv[]);
int fexecve(int fd, char *const argv[], char *const envp[]);
Some implementations provide these functions named w
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https://en.wikipedia.org/wiki/Germ%20pore
|
A germ pore is a small pore in the outer wall of a fungal spore through which the germ tube exits upon germination. It can be apical or eccentric in its location, and, on light microscopy, may be visualized as a lighter coloured area on the cell wall.
Apical germ pore is mushroom spore which has a pore at one end. Some spores have a hole in the cell wall where the first strand of germinating mycelium emerges. If the cell wall is divided from one end to the other, this is called a germ slit. Commonly the germ pore is at one end of the mushroom spore and is called an apical pore.
Mushroom genera with apical germ pores include Agrocybe, Panaeolus, Psilocybe, and Pholiota.
See also
mycelium
spore
External links
IMA Mycological Glossary: Germ pore
Fungal morphology and anatomy
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https://en.wikipedia.org/wiki/Pileipellis
|
The pileipellis is the uppermost layer of hyphae in the pileus of a fungal fruit body. It covers the trama, the fleshy tissue of the fruit body. The pileipellis is more or less synonymous with the cuticle, but the cuticle generally describes this layer as a macroscopic feature, while pileipellis refers to this structure as a microscopic layer. Pileipellis type is an important character in the identification of fungi. Pileipellis types include the cutis, trichoderm, epithelium, and hymeniderm types.
Types
Cutis
A cutis is a type of pileipellis characterized by hyphae that are repent, that is, that run parallel to the pileus surface. In an ixocutis, the hyphae are gelatinous.
Trichoderm
In a trichoderm, the outermost hyphae emerge roughly parallel, like hairs, perpendicular to the cap surface. The prefix "tricho-" comes from a Greek word for "hair". In an ixotrichodermium, the outermost hyphae are gelatinous.
Epithelium
An epithelium is a pileipellis consisting of rounded cells in multiple layers, often connected in chains, and sometimes breaking off.
Hymeniderm
Also called hymeniform, or palisade at times. When viewed from above, a hymeniderm or "cellular cuticle" appears to be paved with roughly circular polygonal elements (similar to the fertile cells of the actual hymenium on the gills). The elements may be globular cells or may be the tips of hyphae extending deeper into the surface.
External links
IMA Mycological Glossary: Pileipellis
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https://en.wikipedia.org/wiki/Pileus%20%28mycology%29
|
The pileus is the technical name for the cap, or cap-like part, of a basidiocarp or ascocarp (fungal fruiting body) that supports a spore-bearing surface, the hymenium. The hymenium (hymenophore) may consist of lamellae, tubes, or teeth, on the underside of the pileus. A pileus is characteristic of agarics, boletes, some polypores, tooth fungi, and some ascomycetes.
Classification
Pilei can be formed in various shapes, and the shapes can change over the course of the developmental cycle of a fungus. The most familiar pileus shape is hemispherical or convex. Convex pilei often continue to expand as they mature until they become flat. Many well-known species have a convex pileus, including the button mushroom, various Amanita species and boletes.
Some, such as the parasol mushroom, have distinct bosses or umbos and are described as umbonate. An umbo is a knobby protrusion at the center of the cap. Some fungi, such as chanterelles have a funnel- or trumpet-shaped appearance. In these cases the pileus is termed infundibuliform.
See also
Lamella
Stipe
Notes
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https://en.wikipedia.org/wiki/Aluminium%20phosphide
|
Aluminium phosphide is a highly toxic inorganic compound with the chemical formula AlP, used as a wide band gap semiconductor and a fumigant. This colorless solid is generally sold as a grey-green-yellow powder due to the presence of impurities arising from hydrolysis and oxidation.
Properties
AlP crystals are dark grey to dark yellow in color and have a zincblende crystal structure with a lattice constant of 5.4510 Å at 300 K. They are thermodynamically stable up to .
Aluminium phosphide reacts with water or acids to release phosphine:
AlP + 3 H2O → Al(OH)3 + PH3
AlP + 3 H+ → Al3+ + PH3
This reaction is the basis of its toxicity.
Preparation
AlP is synthesized by combination of the elements:
4Al + P4 → 4AlP
Caution must be taken to avoid exposing the AlP to any sources of moisture, as this generates toxic phosphine gas. Phosphine also poses fire hazards, as it is a dangerous pyrophoric compound, igniting easily in air.
Uses
Pesticide
AlP is used as a rodenticide, insecticide, and fumigant for stored cereal grains. It is used to kill small verminous mammals such as moles and rodents. The tablets or pellets, known as "wheat pills", typically also contain other chemicals that evolve ammonia and carbon dioxide (e.g. ammonium carbamate), which help to reduce the potential for spontaneous ignition or explosion of the phosphine gas.
AlP is used as both a fumigant and an oral pesticide. As a rodenticide, aluminium phosphide pellets are provided as a mixture with food for consumption by the rodents. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic phosphine gas. Other pesticides similar to aluminium phosphide are zinc phosphide and calcium phosphide. In this application, aluminium phosphide can be encountered under various brand names, e.g. PestPhos,Quickphos, Celphos, Fostox, Fumitoxin, Phostek, Phostoxin, Talunex, Fieldphos, and Weevil-Cide. It generates phosphine gas according to the following hydrolysis equation
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https://en.wikipedia.org/wiki/Intensive%20gathering
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Intensive gathering entails the tending-to of wild plants. Intensive gathering or "tending" methods include weeding, discouraging predators, pot-irrigation, and limited harvesting to ensure reproduction. The same system of methods is involved in cultivation, a process which additionally requires systematic soil preparation and planting to tending and harvesting. This human manipulation results in the domestication of involved plant life.
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https://en.wikipedia.org/wiki/Dystrophy
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Dystrophy is the degeneration of tissue, due to disease or malnutrition, most likely due to heredity.
Types
Muscular dystrophy
Duchenne muscular dystrophy
Becker's muscular dystrophy
Myotonic dystrophy
Reflex neurovascular dystrophy
Retinal dystrophy
Cone dystrophy
Corneal dystrophy
Lipodystrophy
Nail dystrophy
See also
Muscle weakness
Muscle atrophy
Myotonia
List of biological development disorders
Medical terminology
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https://en.wikipedia.org/wiki/Paleolimnology
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Paleolimnology (from Greek: παλαιός, palaios, "ancient", λίμνη, limne, "lake", and λόγος, logos, "study") is a scientific sub-discipline closely related to both limnology and paleoecology. Paleolimnological studies focus on reconstructing the past environments of inland waters (e.g., lakes and streams) using the geologic record, especially with regard to events such as climatic change, eutrophication, acidification, and internal ontogenic processes.
Paleolimnological studies are mostly conducted using analyses of the physical, chemical, and mineralogical properties of sediments, or of biological records such as fossil pollen, diatoms, or chironomids.
History
Lake ontogeny
Most early paleolimnological studies focused on the biological productivity of lakes, and the role of internal lake processes in lake development. Although Einar Naumann had speculated that the productivity of lakes should gradually decrease due to leaching of catchment soils, August Thienemann suggested that the reverse process likely occurred. Early midge records seemed to support Thienemann's view.
Hutchinson and Wollack suggested that, following an initial oligotrophic stage, lakes would achieve and maintain a trophic equilibrium. They also stressed parallels between the early development of lake communities and the sigmoid growth phase of animal communities – implying that the apparent early developmental processes in lakes were dominated by colonization effects, and lags due to the limited reproductive potential of the colonizing organisms.
In a classic paper, Raymond Lindeman outlined a hypothetical developmental sequence, with lakes progressively developing through oligotrophic, mesotrophic, and eutrophic stages, before senescing to a dystrophic stage and then filling completely with sediment. A climax forest community would eventually be established on the peaty fill of the former lake basin. These ideas were further elaborated by Ed Deevey, who suggested that lake development was dom
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https://en.wikipedia.org/wiki/Rugged%20computer
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A rugged computer or ruggedized computer is a computer specifically designed to operate reliably in harsh usage environments and conditions, such as strong vibrations, extreme temperatures and wet or dusty conditions. They are designed from inception for the type of rough use typified by these conditions, not just in the external housing but in the internal components and cooling arrangements as well.
Typical environments for rugged laptops, tablet PCs and PDAs are public safety, field sales, field service, manufacturing, retail, healthcare, construction, transportation/distribution and the military. They are used in the agricultural industries, and by individuals for outdoor recreation activities.
Construction
Virtually all rugged computers share an underlying design philosophy of providing a controlled environment for the installed electronics. Rugged computers are engineered to operate in the face of multiple challenges including:
Shock and vibration
Temperature and humidity
Corrosion and abrasion
Minimal size, weight, and power (SWaP)
Acoustic noise reduction
Low pressure/altitude
Ingress protection
Electromagnetic interference
Optimizations on performance
Electronic components themselves may be selected for their ability to withstand higher and lower operating temperatures than typical commercial components. Design engineering decisions such as reduction of cabling, addition of liquid cooling and heat sinks, and rugged materials, are made to ensure performance in harsh environments.
Features include fully sealed keyboards to protect against intrusion by dust or liquids, and scratch-resistant screens that are readable in direct sunlight.
Rugged units have higher prices. However, one research study found that in environments where rugged computers are commonly used, total cost of ownership was 36% lower for rugged notebooks and 33% less for handhelds and PDAs, compared to conventional non-rugged versions. The lower overall cost is due to lower f
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https://en.wikipedia.org/wiki/Quinarian%20system
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The quinarian system was a method of zoological classification which was popular in the mid 19th century, especially among British naturalists. It was largely developed by the entomologist William Sharp Macleay in 1819. The system was further promoted in the works of Nicholas Aylward Vigors, William John Swainson and Johann Jakob Kaup. Swainson's work on ornithology gave wide publicity to the idea. The system had opponents even before the publication of Charles Darwin's On the Origin of Species (1859), which paved the way for evolutionary trees.
Classification approach
Quinarianism gets its name from the emphasis on the number five: it proposed that all taxa are divisible into five subgroups, and if fewer than five subgroups were known, quinarians believed that a missing subgroup remained to be found.
Presumably this arose as a chance observation of some accidental analogies between different groups, but it was erected into a guiding principle by the quinarians. It became increasingly elaborate, proposing that each group of five classes could be arranged in a circle, with those closer together having greater affinities. Typically they were depicted with relatively advanced groups at the top, and supposedly degenerate forms towards the bottom. Each circle could touch or overlap with adjacent circles; the equivalent overlapping of actual groups in nature was called osculation.
Another aspect of the system was the identification of analogies across groups:
Quinarianism was not widely popular outside the United Kingdom (some followers like William Hincks persisted in Canada); it became unfashionable by the 1840s, during which time more complex "maps" were made by Hugh Edwin Strickland and Alfred Russel Wallace. Strickland and others specifically rejected the use of relations of "analogy" in constructing natural classifications. These systems were eventually discarded in favour of principles of genuinely natural classification, namely based on evolutionary relations
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https://en.wikipedia.org/wiki/BitVault
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BitVault is a content-addressable distributed storage system, developed by Microsoft Research in China. BitVault uses peer-to-peer technology to distribute the tasks of storing and managing data. As such, there is no central authority responsible for management of the system. Rather, it is self-managing, provides high availability, reliability and scales up in a self-organizing manner, with low administrative overhead, which is almost constant irrespective of the size of the distributed overlay network.
BitVault system is best suited for reference data, which is large amount of data which changes very infrequently. Such data include archives of out-of-date data, as well as multimedia data like music and video, which, even though might be frequently used, changes very rarely.
Technology
Every participating peer node in BitVault architecture is a Smart Brick, which is a trimmed down PC with large disks. All Smart Bricks in a BitVault system are connected by a high-bandwidth, low latency network. A BitVault system can be easily scaled up – any computer can be configured to act as a Smart Brick by simply installing the BitVault software, and connecting it to the network, without any need for interrupting the already working nodes.
BitVault stores immutable data objects, i.e., objects which cannot be changed. The physical location of the objects is not fixed and can be on any of the bricks. Its location changes depending on its frequency of access; it can even be replicated at more than one brick. To get around this problem of changing locations, BitVault makes it accessible by means of a 160-bit key, which is unique for each object. The system dynamically references the location from which the object can be retrieved most efficiently, by using the key, and makes the object available. The unique key is generated from a hash of the data of the object, thus making the system content-addressable, as opposed to location-addressable. The hashes of the objects (key) are map
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https://en.wikipedia.org/wiki/Hypothetical%20protein
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In biochemistry, a hypothetical protein is a protein whose existence has been predicted, but for which there is a lack of experimental evidence that it is expressed in vivo. Sequencing of several genomes has resulted in numerous predicted open reading frames to which functions cannot be readily assigned. These proteins, either orphan or conserved hypothetical proteins, make up an estimated 20% to 40% of proteins encoded in each newly sequenced genome. The real evidences for the hypothetical protein functioning in the metabolism of the organism can be predicted by comparing its sequence or structure homology by considering the conserved domain analysis. Even when there is enough evidence that the product of the gene is expressed, by techniques such as microarray and mass spectrometry, it is difficult to assign a function to it given its lack of identity to protein sequences with annotated biochemical function. Nowadays, most protein sequences are inferred from computational analysis of genomic DNA sequence. Hypothetical proteins are created by gene prediction software during genome analysis. When the bioinformatic tool used for the gene identification finds a large open reading frame without a characterised homologue in the protein database, it returns "hypothetical protein" as an annotation remark.
The function of a hypothetical protein can be predicted by domain homology searches with various confidence levels. Conserved domains are available in the hypothetical proteins which need to be compared with the known family domains by which hypothetical protein could be classified into particular protein families even though they have not been in vivo investigated. The function of hypothetical protein could also be predicted by homology modelling, in which hypothetical protein has to align with known protein sequence whose three dimensional structure is known and by modelling method if structure predicted then the capability of hypothetical protein to function could b
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https://en.wikipedia.org/wiki/Admissible%20ordinal
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In set theory, an ordinal number α is an admissible ordinal if Lα is an admissible set (that is, a transitive model of Kripke–Platek set theory); in other words, α is admissible when α is a limit ordinal and Lα ⊧ Σ0-collection. The term was coined by Richard Platek in 1966.
The first two admissible ordinals are ω and (the least nonrecursive ordinal, also called the Church–Kleene ordinal). Any regular uncountable cardinal is an admissible ordinal.
By a theorem of Sacks, the countable admissible ordinals are exactly those constructed in a manner similar to the Church–Kleene ordinal, but for Turing machines with oracles. One sometimes writes for the -th ordinal that is either admissible or a limit of admissibles; an ordinal that is both is called recursively inaccessible. There exists a theory of large ordinals in this manner that is highly parallel to that of (small) large cardinals (one can define recursively Mahlo ordinals, for example). But all these ordinals are still countable. Therefore, admissible ordinals seem to be the recursive analogue of regular cardinal numbers.
Notice that α is an admissible ordinal if and only if α is a limit ordinal and there does not exist a γ < α for which there is a Σ1(Lα) mapping from γ onto α. is an admissible ordinal iff there is a standard model of KP whose set of ordinals is , in fact this may be take as the definition of admissibility. The th admissible ordinal is sometimes denoted by p.174 or .
The Friedman-Jensen-Sacks theorem states that countable is admissible iff there exists some such that is the least ordinal not recursive in .
See also
α-recursion theory
Large countable ordinals
Constructible universe
Regular cardinal
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https://en.wikipedia.org/wiki/Advantage%20%28cryptography%29
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In cryptography, an adversary's advantage is a measure of how successfully it can attack a cryptographic algorithm, by distinguishing it from an idealized version of that type of algorithm. Note that in this context, the "adversary" is itself an algorithm and not a person. A cryptographic algorithm is considered secure if no adversary has a non-negligible advantage, subject to specified bounds on the adversary's computational resources (see concrete security). "Negligible" usually means "within O(2−p)" where p is a security parameter associated with the algorithm. For example, p might be the number of bits in a block cipher's key.
Description of concept
Let F be an oracle for the function being studied, and let G be an oracle for an idealized function of that type. The adversary A is a probabilistic algorithm, given F or G as input, and which outputs 1 or 0. A's job is to distinguish F from G, based on making queries to the oracle that it's given. We say:
Examples
Let F be a random instance of the DES block cipher. This cipher has 64-bit blocks and a 56-bit key. The key therefore selects one of a family of 256 permutations on the 264 possible 64-bit blocks. A "random DES instance" means our oracle F computes DES using some key K (which is unknown to the adversary) where K is selected from the 256 possible keys with equal probability.
We want to compare the DES instance with an idealized 64-bit block cipher, meaning a permutation selected at random from the (264)! possible permutations on 64-bit blocks. Call this randomly selected permutation G. Note from Stirling's approximation that (264)! is around , so even specifying which permutation is selected requires writing down a number too large to represent exactly in any real computer. Viewed another way, G is an instance of a "cipher" whose "key length" is about 1021 bits, which again is too large to fit in a computer. (We can, however, implement G with storage space proportional to the number of q
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https://en.wikipedia.org/wiki/Access%20Linux%20Platform
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The Access Linux Platform (ALP) is a discontinued open-source software based operating system, once referred to as a "next-generation version of the Palm OS," for mobile devices developed and marketed by Access Co., of Tokyo, Japan. The platform included execution environments for Java, classic Palm OS, and GTK+-based native Linux applications. ALP was demonstrated in devices at a variety of conferences, including 3GSM, LinuxWorld, GUADEC, and Open Source in Mobile.
The ALP was first announced in February 2006. The initial versions of the platform and software development kits were officially released in February 2007. There was a coordinated effort by Access, Esteemo, NEC, NTT DoCoMo, and Panasonic to use the platform as a basis for a shared platform implementing a revised version of the i.mode Mobile Oriented Applications Platform (MOAP) (L) application programming interfaces (APIs), conforming to the specifications of the LiMo Foundation. The first smartphone to use the ALP was to be the Edelweiss by Emblaze Mobile that was scheduled for mid-2009. However, it was shelved before release. The First Else (renamed from Monolith) smartphone, that was being developed by Sharp Corporation in cooperation with Emblaze Mobile and seven other partners, was scheduled for 2009, but was never released and officially cancelled in June 2010. The platform is no longer referenced on Access's website, but Panasonic and NEC released a number of ALP phones for the Japanese market between 2010 and 2013.
Look and feel
The user interface was designed with similar general goals to earlier Palm OS releases, with an aim of preserving the Zen of Palm, a design philosophy centered on making the applications as simple as possible. Other aspects of the interface included a task-based orientation rather than a file/document orientation as is commonly found on desktop systems.
The appearance of the platform was intended to be highly customizable to provide differentiation for specific device
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https://en.wikipedia.org/wiki/Charge-transfer%20insulators
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Charge-transfer insulators are a class of materials predicted to be conductors following conventional band theory, but which are in fact insulators due to a charge-transfer process. Unlike in Mott insulators, where the insulating properties arise from electrons hopping between unit cells, the electrons in charge-transfer insulators move between atoms within the unit cell. In the Mott–Hubbard case, it's easier for electrons to transfer between two adjacent metal sites (on-site Coulomb interaction U); here we have an excitation corresponding to the Coulomb energy U with
.
In the charge-transfer case, the excitation happens from the anion (e.g., oxygen) p level to the metal d level with the charge-transfer energy Δ:
.
U is determined by repulsive/exchange effects between the cation valence electrons. Δ is tuned by the chemistry between the cation and anion. One important difference is the creation of an oxygen p hole, corresponding to the change from a 'normal' O^2- to the ionic O- state. In this case the ligand hole is often denoted as .
Distinguishing between Mott-Hubbard and charge-transfer insulators can be done using the Zaanen-Sawatzky-Allen (ZSA) scheme.
Exchange Interaction
Analogous to Mott insulators we also have to consider superexchange in charge-transfer insulators. One contribution is similar to the Mott case: the hopping of a d electron from one transition metal site to another and then back the same way. This process can be written as
.
This will result in an antiferromagnetic exchange (for nondegenerate d levels) with an exchange constant .
In the charge-transfer insulator case
.
This process also yields an antiferromagnetic exchange :
The difference between these two possibilities is the intermediate state, which has one ligand hole for the first exchange () and two for the second ().
The total exchange energy is the sum of both contributions:
.
Depending on the ratio of , the process is dominated by one of the terms and thus the resu
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https://en.wikipedia.org/wiki/Coefficient%20matrix
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In linear algebra, a coefficient matrix is a matrix consisting of the coefficients of the variables in a set of linear equations. The matrix is used in solving systems of linear equations.
Coefficient matrix
In general, a system with linear equations and unknowns can be written as
where are the unknowns and the numbers are the coefficients of the system. The coefficient matrix is the matrix with the coefficient as the th entry:
Then the above set of equations can be expressed more succinctly as
where is the coefficient matrix and is the column vector of constant terms.
Relation of its properties to properties of the equation system
By the Rouché–Capelli theorem, the system of equations is inconsistent, meaning it has no solutions, if the rank of the augmented matrix (the coefficient matrix augmented with an additional column consisting of the vector ) is greater than the rank of the coefficient matrix. If, on the other hand, the ranks of these two matrices are equal, the system must have at least one solution. The solution is unique if and only if the rank equals the number of variables. Otherwise the general solution has free parameters; hence in such a case there are an infinitude of solutions, which can be found by imposing arbitrary values on of the variables and solving the resulting system for its unique solution; different choices of which variables to fix, and different fixed values of them, give different system solutions.
Dynamic equations
A first-order matrix difference equation with constant term can be written as
where is and and are . This system converges to its steady-state level of if and only if the absolute values of all eigenvalues of are less than 1.
A first-order matrix differential equation with constant term can be written as
This system is stable if and only if all eigenvalues of have negative real parts.
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https://en.wikipedia.org/wiki/Matrix%20grammar
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A matrix grammar is a formal grammar in which instead of single productions, productions are grouped together into finite sequences. A production cannot be applied separately, it must be applied in sequence. In the application of such a sequence of productions, the rewriting is done in accordance to each production in sequence, the first one, second one etc. till the last production has been used for rewriting. The sequences are referred to as matrices.
Matrix grammar is an extension of context-free grammar, and one instance of a controlled grammar.
Formal definition
A matrix grammar is an ordered quadruple
where
is a finite set of non-terminals
is a finite set of terminals
is a special element of , viz. the starting symbol
is a finite set of non-empty sequences whose elements are ordered pairs where
The pairs are called productions, written as . The sequences are called matrices and can be written as
Let be the set of all productions appearing in the matrices of a matrix grammar . Then the matrix grammar is of type-, length-increasing, linear, -free, context-free or context-sensitive if and only if the grammar has the following property.
For a matrix grammar , a binary relation is defined; also represented as . For any , holds if and only if there exists an integer such that the words
over V exist and
and
is one of the matrices of
and for all such that
Let be the reflexive transitive closure of the relation . Then, the language generated by the matrix grammar is given by
Examples
Consider the matrix grammar
where is a collection containing the following matrices:
These matrices, which contain only context-free rules, generate the context-sensitive language
The associate word of
is
and
.
This example can be found on pages 8 and 9 of in the following form:
Consider the matrix grammar
where is a collection containing the following matrices:
These matrices, which contain only context-regular rules, generate the conte
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https://en.wikipedia.org/wiki/Neugebauer%20equations
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The Neugebauer equations are a set of equations used to model color printing systems, developed by Hans E. J. Neugebauer. They were intended to predict the color produced by a combination of halftones printed in cyan, magenta, and yellow inks.
The equations estimate the reflectance (in CIE XYZ coordinates or as a function of wavelength) as a function of the reflectance of the 8 possible combinations of CMY inks (or the 16 combinations of CMYK inks), weighted by the area they take up on the paper. In wavelength form:
where Ri(λ) is the reflectance of ink combination i, and wi is the relative proportions of the 16 colors in a uniformly colored patch. The weights are dependent on the halftone pattern and possibly subject to various forms of dot gain.
Light can interact with the paper and ink in more complex ways. The Yule–Nielsen correction takes into account light entering through blank regions and re-emerging through ink:
The factor n would be 2 for a perfectly diffusing Lambertian paper substrate, but can be adjusted based on empirical measurements. Further considerations of the optics, such as multiple internal reflections, can be added at the price of additional complexity.
In order to achieve a desired reflectance, these equations have to be inverted to produce the actual dot areas or digital values sent to the printer, a nontrivial operation that may have multiple solutions.
See also
CMYK color model
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https://en.wikipedia.org/wiki/Chorionic%20villi
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Chorionic villi are villi that sprout from the chorion to provide maximal contact area with maternal blood.
They are an essential element in pregnancy from a histomorphologic perspective, and are, by definition, a product of conception. Branches of the umbilical arteries carry embryonic blood to the villi. After circulating through the capillaries of the villi, blood returns to the embryo through the umbilical vein. Thus, villi are part of the border between maternal and fetal blood during pregnancy.
Structure
Villi can also be classified by their relations:
Floating villi float freely in the intervillous space. They exhibit a bi-layered epithelium consisting of cytotrophoblasts with overlaying syncytium (syncytiotrophoblast).
Anchoring (stem) villi stabilize the mechanical integrity of the placental-maternal interface.
Development
The chorion undergoes rapid proliferation and forms numerous processes, the chorionic villi, which invade and destroy the uterine decidua and at the same time absorb from it nutritive materials for the growth of the embryo. They undergo several stages, depending on their composition.
Until about the end of the second month of pregnancy, the villi cover the entire chorion, and are almost uniform in size—but after then, they develop unequally.
Microanatomy
The bulk of the villi consist of connective tissues that contain blood vessels. Most of the cells in the connective tissue core of the villi are fibroblasts. Macrophages known as Hofbauer cells are also present.
Clinical significance
Use for prenatal diagnosis
In 1983, an Italian biologist named Giuseppe Simoni discovered a new method of prenatal diagnosis using chorionic villi.
Stem cell
Chorionic villi are a rich source of stem cells. Biocell Center, a biotech company managed by Giuseppe Simoni, is studying and testing these types of stem cells. Chorionic stem cells, like amniotic stem cells, are uncontroversial multipotent stem cells.
Infections
Recent studies indicate th
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https://en.wikipedia.org/wiki/2010%20Biodiversity%20Target
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The 2010 Biodiversity Target was an overall conservation target aiming to halt the decline of biodiversity by the end of 2010. The world largely failed to meet the target.
History of the 2010 Biodiversity Target
It was first adopted by EU Heads of State at the EU Summit in Gothenburg, Sweden, in June 2001. They decided that "biodiversity decline should be halted with the aim of reaching this objective by 2010".
One year later, the Convention on Biological Diversity's sixth Conference of the Parties adopted the Strategic Plan for the Convention in Decision VI/26. The Decision says "Parties commit themselves to a more effective and coherent implementation of the three objectives of the Convention, to achieve by 2010 a significant reduction of the current rate of biodiversity loss at the global, regional and national level as a contribution to poverty alleviation and to the benefit of all life on earth."
The World Summit on Sustainable Development held in Johannesburg in 2002 confirmed the 2010 Biodiversity Target and called for "the achievement by 2010 of a significant reduction in the current rate of loss of biological diversity".
In 2003, Environment Ministers and Heads of delegation from 51 countries in the United Nations Economic Commission for Europe (UNECE) region adopted the Kiev Resolution on Biodiversity at the fifth Ministerial Conference "Environment for Europe" and decided to "reinforce our objective to halt the loss of biological diversity at all levels by the year 2010".
By the year 2006, the following nations have contributed extensively to establishment of individual Biodiversity Action Plans: Tanzania, New Zealand, Great Britain and the United States of America, called Species Recovery Plans in the USA.
Progress at the European Level
The 2004 Irish Presidency held a major stakeholder conference on the 2010 Biodiversity Target which resulted in a detailed roadmap to 2010 called the "Message from Malahide". At the same time, a number of organisat
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https://en.wikipedia.org/wiki/Comparison%20of%20video%20hosting%20services
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The following tables compare general and technical information for a number of current, notable video hosting services. Please see the individual products' articles for further information.
General information
Basic general information about the hosts: creator/company, license/price etc.
Supported input file formats
All services support the following input file formats:
Moving Picture Experts Group (.MPG/MPEG-1)
QuickTime File Format (.MOV)
Windows Media Video (.WMV)
Audio Video Interleave (.AVI)
H.264 MPEG-4/AVC (.MP4)
Unless otherwise indicated, they also support the following input file formats:
Matroska Multimedia Container (.MKV)
Theora (.OGV)
3rd Generation Partnership Project (.3GP)
Streaming video technical information
Site traffic
Specifically dedicated video hosting websites
* Website predominantly hosts live streaming video.
See also
Comparison of streaming media software
Content delivery network
Streaming television
Internet Protocol television
Comparison of music streaming services
List of streaming media systems
List of online video platforms
Multicast
One-click hosting
P2PTV
Protection of Broadcasts and Broadcasting Organizations Treaty
Push technology
Streaming media
Video on demand
Webcast
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