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https://en.wikipedia.org/wiki/The%20Ambidextrous%20Universe | The Ambidextrous Universe is a popular science book by Martin Gardner, covering aspects of symmetry and asymmetry in human culture, science and the wider universe. It culminates in a discussion of whether nature's conservation of parity (the symmetry of mirrored quantum systems) is ever violated, which had been proven experimentally in 1956.
The book was originally published in 1964 with the subtitle Left, Right, and the Fall of Parity, with a revised version following in 1969. A second edition was released in 1979 with the new subtitle Mirror Asymmetry and Time-Reversed Worlds. The third edition was released in 1990 under the title The New Ambidextrous Universe: Symmetry and Asymmetry from Mirror Reflections to Superstrings; this was with minor revisions in 2005.
Content
The book begins with the subject of mirror reflection, and from there passes through symmetry in geometry, poetry, art, music, galaxies, stars, planets and living organisms. It then moves down into the molecular scale and looks at how symmetry and asymmetry have evolved from the beginning of life on Earth. There is a chapter on carbon and its versatility and on chirality in biochemistry.
The last several chapters deal with a conundrum called the Ozma Problem, which examines whether there is any fundamental asymmetry to the universe. This discussion concerns various aspects of atomic and subatomic physics and how they relate to mirror asymmetry and the related concepts of chirality, antimatter, magnetic and electrical polarity, parity, charge and spin. Time invariance (and reversal) is discussed. Implications for particle physics, theoretical physics and cosmology are covered and brought up to date (in later editions of the book) with regard to Grand Unified Theories, theories of everything, superstring theory and .
The Ozma Problem
The 18th chapter, "The Ozma Problem", poses a problem that Gardner claims would arise if Earth should ever enter into communication with life on another planet thro |
https://en.wikipedia.org/wiki/Vessel%20emergency%20codes | In addition to distress signals like Mayday and pan-pan, most vessels, especially passenger ships, use some emergency signals to alert the crew on board. In some cases, the signals may alert the passengers to danger, but, in others, the objective is to conceal the emergency from unaffected passengers so as to avoid panic or undue alarm. Signals can be in the form of blasts on alarm bells, sounds on the ship's whistle or code names paged over the PA system.
Alpha, Alpha, Alpha is the code for a medical emergency aboard Royal Caribbean ships.
Alpha Team, Alpha Team, Alpha Team is the code for a fire emergency aboard Carnival Cruise Line ships.
Assemble at Muster Stations (General Emergency Signal), seven short blasts followed by one long blast of the ships horn and internal alarm bell system.
Bravo, Bravo, Bravo is used by many cruise lines to alert crew to a fire or other serious incident on board without alarming passengers.
Operation Brightstar designates a medical emergency, such as cardiac or stroke on Carnival and Disney Cruise Line vessels. It can only be requested to be announced by one of the medical team or an officer with advanced medical training. The spoken word Brightstar over the PA, sometimes supplemented by a group signal on the pager system will alert the medical team including all doctors and nurses to attend the location. The ventilation officer (VO) is also alerted during a Brightstar. The VO will start the power to the cooling in the morgue (presuming it is not already in use) as a precaution.
Charlie, Charlie, Charlie is the code for a security threat aboard Royal Caribbean ships and the code for upcoming helicopter winch operations aboard c-bed accommodation vessels.
Code Blue usually means a medical emergency.
Delta, Delta, Delta is the code for a possible bio-hazard among some cruise lines. More commonly used to alert crew to hull damage on board some lines as well.
Echo, Echo, Echo is the code for a possible collision with another ship or t |
https://en.wikipedia.org/wiki/Acceleration%20%28human%20development%29 | Acceleration in human development process is the phenomenon which has been registered in many populations around the world. This applies equally to the growth of certain anthropometric parameters and the speed of reaching sexual maturity. These facts illustrate the results of secular changes in body height and appearance of the first menstruation (menarche).
Increases in human stature are a main indicator of improvements in the average health of populations. The newest data set for the average height of adult male birth cohorts, from the mid-nineteenth century to 1980, in 15 European countries was studied (in the populations listed).
During a century average height increased by 11 cm representing a dramatic improvement of this phenomenon. The apparent acceleration of body height occurred during the periods around the two World Wars and after the Great Depression.
In the mid-nineteenth century European girls' menarche occurred at the average age of 16.5 years. One hundred years later, this age was reduced to under 12 years.
Increase in adult height of birth cohorts (cm/decade)
See also
Human body development |
https://en.wikipedia.org/wiki/Common%20integrals%20in%20quantum%20field%20theory | Common integrals in quantum field theory are all variations and generalizations of Gaussian integrals to the complex plane and to multiple dimensions. Other integrals can be approximated by versions of the Gaussian integral. Fourier integrals are also considered.
Variations on a simple Gaussian integral
Gaussian integral
The first integral, with broad application outside of quantum field theory, is the Gaussian integral.
In physics the factor of 1/2 in the argument of the exponential is common.
Note:
Thus we obtain
Slight generalization of the Gaussian integral
where we have scaled
Integrals of exponents and even powers of x
and
In general
Note that the integrals of exponents and odd powers of x are 0, due to odd symmetry.
Integrals with a linear term in the argument of the exponent
This integral can be performed by completing the square:
Therefore:
Integrals with an imaginary linear term in the argument of the exponent
The integral
is proportional to the Fourier transform of the Gaussian where is the conjugate variable of .
By again completing the square we see that the Fourier transform of a Gaussian is also a Gaussian, but in the conjugate variable. The larger is, the narrower the Gaussian in and the wider the Gaussian in . This is a demonstration of the uncertainty principle.
This integral is also known as the Hubbard–Stratonovich transformation used in field theory.
Integrals with a complex argument of the exponent
The integral of interest is (for an example of an application see Relation between Schrödinger's equation and the path integral formulation of quantum mechanics)
We now assume that and may be complex.
Completing the square
By analogy with the previous integrals
This result is valid as an integration in the complex plane as long as is non-zero and has a semi-positive imaginary part. See Fresnel integral.
Gaussian integrals in higher dimensions
The one-dimensional integrals can be generalized to multiple dimensions.
Her |
https://en.wikipedia.org/wiki/Lexell%27s%20theorem | In spherical geometry, Lexell's theorem holds that every spherical triangle with the same surface area on a fixed base has its apex on a small circle, called Lexell's circle or Lexell's locus, passing through two points antipodal to the two base vertices.
The theorem is named for Anders Johan Lexell, who presented a paper about it (published 1784) including both a trigonometric proof and a geometric one. Lexell's colleague Leonhard Euler wrote another pair of proofs in 1778 (published 1797), and a variety of proofs have been written since by Adrien-Marie Legendre (1800), Jakob Steiner (1827), Carl Friedrich Gauss (1841), Paul Serret (1855), and Joseph-Émile Barbier (1864), among others.
The theorem is the analog of propositions 37 and 39 in Book I of Euclid's Elements, which prove that every planar triangle with the same area on a fixed base has its apex on a straight line parallel to the base. An analogous theorem can also be proven for hyperbolic triangles, for which the apex lies on a hypercycle.
Statement
Given a fixed base an arc of a great circle on a sphere, and two apex points and on the same side of great circle Lexell's theorem holds that the surface area of the spherical triangle is equal to that of if and only if lies on the small-circle arc where and are the points antipodal to and respectively.
As one analog of the planar formula for the area of a triangle, the spherical excess of spherical triangle can be computed in terms of the base (the angular length of arc and "height" (the angular distance between the parallel small circles
In the limit for triangles much smaller than the radius of the sphere, this reduces to the planar formula.
The small circles and each intersect the great circle at an angle of
Proofs
There are several ways to prove Lexell's theorem, each illuminating a different aspect of the relationships involved.
Isosceles triangles
The main idea in Lexell's geometric proof – also adopted by Eugène Cat |
https://en.wikipedia.org/wiki/Projective%20differential%20geometry | In mathematics, projective differential geometry is the study of differential geometry, from the point of view of properties of mathematical objects such as functions, diffeomorphisms, and submanifolds, that are invariant under transformations of the projective group. This is a mixture of the approaches from Riemannian geometry of studying invariances, and of the Erlangen program of characterizing geometries according to their group symmetries.
The area was much studied by mathematicians from around 1890 for a generation (by J. G. Darboux, George Henri Halphen, Ernest Julius Wilczynski, E. Bompiani, G. Fubini, Eduard Čech, amongst others), without a comprehensive theory of differential invariants emerging. Élie Cartan formulated the idea of a general projective connection, as part of his method of moving frames; abstractly speaking, this is the level of generality at which the Erlangen program can be reconciled with differential geometry, while it also develops the oldest part of the theory (for the projective line), namely the Schwarzian derivative, the simplest projective differential invariant.
Further work from the 1930s onwards was carried out by J. Kanitani, Shiing-Shen Chern, A. P. Norden, G. Bol, S. P. Finikov and G. F. Laptev. Even the basic results on osculation of curves, a manifestly projective-invariant topic, lack any comprehensive theory. The ideas of projective differential geometry recur in mathematics and its applications, but the formulations given are still rooted in the language of the early twentieth century.
See also
Affine geometry of curves |
https://en.wikipedia.org/wiki/NSA%20Suite%20A%20Cryptography | NSA Suite A Cryptography is NSA cryptography which "contains classified algorithms that will not be released." "Suite A will be used for the protection of some categories of especially sensitive information (a small percentage of the overall national security-related information assurance market)."
Incomplete list of Suite A algorithms:
ACCORDION
BATON
CDL 1
CDL 2
FFC
FIREFLY
JOSEKI
KEESEE
MAYFLY
MEDLEY
MERCATOR
SAVILLE
SHILLELAGH
WALBURN
WEASEL
See also
Commercial National Security Algorithm Suite
NSA Suite B Cryptography |
https://en.wikipedia.org/wiki/The%20Sixth%20Extinction%3A%20An%20Unnatural%20History | The Sixth Extinction: An Unnatural History is a 2014 non-fiction book written by Elizabeth Kolbert and published by Henry Holt and Company. The book argues that the Earth is in the midst of a modern, man-made, sixth extinction. In the book, Kolbert chronicles previous mass extinction events, and compares them to the accelerated, widespread extinctions during our present time. She also describes specific species extinguished by humans, as well as the ecologies surrounding prehistoric and near-present extinction events. The author received the Pulitzer Prize for General Non-Fiction for the book in 2015.
The target audience is the general reader, and scientific descriptions are rendered in understandable prose. The writing blends explanations of her treks to remote areas with interviews of scientists, researchers, and guides, without advocating a position, in pursuit of objectivity. Hence, the sixth mass extinction theme is applied to flora and fauna existing in diverse habitats, such as the Panamanian rainforest, the Great Barrier Reef, the Andes, Bikini Atoll, city zoos, and the author's own backyard. The book also applies this theme to a number of other habitats and organisms throughout the world. After researching the current mainstream view of the relevant peer-reviewed science, Kolbert estimates flora and fauna loss by the end of the 21st century to be between 20 and 50 percent "of all living species on earth".
Anthropocene
Kolbert equates current, general unawareness of this issue to previous widespread disbelief of it during the centuries preceding the late 1700s; at that time, it was believed that prehistoric mass extinctions had never occurred. It was also believed there were no natural forces powerful enough to extinguish species en masse. Likewise, in our own time, the possible finality presented by this issue results in denialism. But scientific studies have shown that human behavior disrupts Earth's balanced and interconnected systems, "putting our own |
https://en.wikipedia.org/wiki/Shark%20agonistic%20display | Agonism is a broad term which encompasses many behaviours that result from, or are triggered by biological conflict between competing organisms. Approximately 23 shark species are capable of producing such displays when threatened by intraspecific or interspecific competitors, as an evolutionary strategy to avoid unnecessary combat. The behavioural, postural, social and kinetic elements which comprise this complex, ritualized display can be easily distinguished from normal, or non-display behaviour, considered typical of that species' life history. The display itself confers pertinent information to the foe regarding the displayer's physical fitness, body size, inborn biological weaponry, confidence and determination to fight. This behaviour is advantageous because it is much less biologically taxing for an individual to display its intention to fight than the injuries it would sustain during conflict, which is why agonistic displays have been reinforced through evolutionary time, as an adaptation to personal fitness. Agonistic displays are essential to the social dynamics of many biological taxa, extending far beyond sharks.
Characteristics
Definition
Agonistic displays are ritualized sequences of actions, produced by animals belonging to almost all biological taxa, in response to conflict with other organisms. If challenged or threatened, animals may employ a suite of adaptive behaviours, which are used to reinforce the chances of their own survival. Behaviours which arise from agonistic conflict include:
fight or flight response
threat display to warn competitors and signal honest intentions
defence behaviour
simulated paralysis
avoidance behaviour
withdrawal
settling behaviour.
Each of these listed strategies constitute some manifestation of agonistic behaviour, and have been observed in numerous shark species, among many higher taxa in Kingdom Animalia. Displays of this nature are influenced and reinforced by natural selection, as an optimal strategy for |
https://en.wikipedia.org/wiki/Scar | A scar (or scar tissue) is an area of fibrous tissue that replaces normal skin after an injury. Scars result from the biological process of wound repair in the skin, as well as in other organs, and tissues of the body. Thus, scarring is a natural part of the healing process. With the exception of very minor lesions, every wound (e.g., after accident, disease, or surgery) results in some degree of scarring. An exception to this are animals with complete regeneration, which regrow tissue without scar formation.
Scar tissue is composed of the same protein (collagen) as the tissue that it replaces, but the fiber composition of the protein is different; instead of a random basketweave formation of the collagen fibers found in normal tissue, in fibrosis the collagen cross-links and forms a pronounced alignment in a single direction. This collagen scar tissue alignment is usually of inferior functional quality to the normal collagen randomised alignment. For example, scars in the skin are less resistant to ultraviolet radiation, and sweat glands and hair follicles do not grow back within scar tissues. A myocardial infarction, commonly known as a heart attack, causes scar formation in the heart muscle, which leads to loss of muscular power and possibly heart failure. However, there are some tissues (e.g. bone) that can heal without any structural or functional deterioration.
Types
All scarring is composed of the same collagen as the tissue it has replaced, but the composition of the scar tissue, compared to the normal tissue, is different. Scar tissue also lacks elasticity unlike normal tissue which distributes fiber elasticity. Scars differ in the amounts of collagen overexpressed. Labels have been applied to the differences in overexpression. Two of the most common types are hypertrophic and keloid scarring, both of which experience excessive stiff collagen bundled growth overextending the tissue, blocking off regeneration of tissues. Another form is atrophic scarrin |
https://en.wikipedia.org/wiki/OS4000 | OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers. OS4000 was developed through to late 1990s, and has been in a support-only mode since then.
History
The first operating systems for the GEC 4000 series were COS (Core Operating System) and DOS (Disk Operating System). These were basically single-user multi-tasking operating systems, designed for developing and running Process control type applications.
OS4000 was first released around 1977. It reused many of the parts of DOS, but added multi-user access, OS4000 JCL Command-line interpreter, Batch processing, OS4000 hierarchical filesystem (although on-disk format very similar to the non-hierarchical DOS filesystem). OS4000 JCL was based on the Cambridge University Phoenix command interpreter.
OS4000 Rel 3 arrived around 1980, and included Linked-OS — support for Linked OS4000 operating systems to enable multi-node systems to be constructed. The main customer for this was the central computing service of University College London (Euclid), where a multi-node system consisting of a Hub file server and multiple Rim multi-access compute server systems provided service for over 100 simultaneous users. Linked-OS was also used to construct fail-over Process control systems with higher resilience.
OS4000 Rel 4 arrived around 1983, and upped the maximum number of user modules to 150 (again, mainly for the University College London Euclid system), together with an enhanced Batch processing system. It also included support for the GEC 4090 processor, which introduced a 32-bit addressing mode.
OS4000 Rel 5 introduced a modified version of the OS4000 filesystem called CFSX, in order to allow easier use of larger disks. The initial Rel 5 only supported the CFSX filesystem, but support for the original CFS1 filesystem was reintroduced as well quite quickly.
OS4000 Rel 6 introduced support |
https://en.wikipedia.org/wiki/ShEx | Shape Expressions (ShEx) is a data modelling language for validating and describing a Resource Description Framework (RDF).
It was proposed at the 2012 RDF Validation Workshop as a high-level, concise language for RDF validation.
The shapes can be defined in a human-friendly compact syntax called ShExC or using any RDF serialization formats like JSON-LD or Turtle.
ShEx expressions can be used both to describe RDF and to automatically check the conformance of RDF data.
The syntax of ShEx is similar to Turtle and SPARQL while the semantics is inspired by regular expression languages like RelaxNG.
Example
PREFIX : <http://example.org/>
PREFIX schema: <http://schema.org/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
:Person {
schema:name xsd:string ;
schema:knows @:Person * ;
}
The previous example declares that nodes conforming to shape Person must have one property schema:name with a string value and zero or more properties schema:knows whose values must conform with shape Person.
Implementations
Online playgrounds and demos
ShExSimple: Online demo based on shex.js
rdfshape: online demo based on shaclex |
https://en.wikipedia.org/wiki/Ficus%20pumila | Ficus pumila, commonly known as the creeping fig or climbing fig, is a species of flowering plant in the mulberry family, native to East Asia (China, Japan, Vietnam) and naturalized in parts of the southeastern and south-central United States. It is also found in cultivation as a houseplant. The Latin specific epithet pumila means "dwarf", and refers to the very small leaves of the plant.
Description
Ficus pumila is a woody evergreen liana, growing to . It can grow up to tall if it isn't regularly pruned. The juvenile foliage is much smaller and thinner than mature leaves produced as the plant ages. The leaves are oval, cordate, asymmetrical, with opposite veins. It is creeping or can behave like a liana and also climb trees, rocks, etc. up to 4 m in height or more. The aerial roots secrete a translucent latex that hardens on drying, allowing the sticks to adhere to their support.
Cultivation
As the common name, "creeping fig" indicates, the plant has a creeping/vining habit and is often used in gardens and landscapes where it covers the ground and climbs up trees and walls. It is hardy down to and does not tolerate frost. Therefore in temperate regions it is often seen as a houseplant. It is fast-growing and requires little in the way of care. It can be invasive when environmental conditions are favorable. Its secondary roots or tendrils can cause structural damage to certain buildings with fragile mortar or structures made of fragile materials.
It has gained the Royal Horticultural Society's Award of Garden Merit.
The plant requires the fig wasp Blastophaga pumilae for pollination, and is fed upon by larvae of the butterfly Marpesia petreus.
Varieties and cultivars
Ficus pumila var. awkeotsang — awkeotsang creeping fig
Ficus pumila var. quercifolia — oak leaf creeping fig
Ficus pumila 'Curly' — curly creeping fig; crinkled leaf form
Ficus pumila 'Variegata' and Ficus pumila 'Snowflake' — variegated creeping fig; variegated foliage
Cuisine
The fruit of |
https://en.wikipedia.org/wiki/The%20European%20%282009%20magazine%29 | The European is a German magazine published in Berlin, Germany. The magazine's name does not describe a thematic of geographic focus but alludes to the discursive tradition of European culture and politics.
History and profile
The European was first published in September 2009. Its publisher and editor-in-chief is Alexander Görlach, former editor-in-chief of Cicero Online, who previously worked for both ZDF and Frankfurter Allgemeine Zeitung. The magazine's office is located in Berlin, Germany.
The European features opinion articles, regular columns and interviews. Its claim is "Views, not News". According to its mission statement, "The European is an opinion magazine". Its authors "debate important political and cultural issues within the framework of journalistic news analysis."
Opinion articles are grouped into thematically focused debates and are contributed by outside "experts" from academia, media, politics, business, science, and culture. Prominent contributors include José Manuel Barroso, Fareed Zakaria, Nicholas Siegel, Martti Ahtisaari, Gareth Evans, Joseph Stiglitz, and Steven Pinker. According to Görlach, The European does not have a specific political leaning but strives to bring differing opinions into dialogue with each other. The German version of the magazine also features a growing circle of regular columnists who write about topics that range from domestic politics to gender issues, European economics, digital culture, and the media.
The magazine is financed through advertising, event organizing and through the work of a separate consulting business, which aims to aid companies and organizations with their social media and outreach strategies. Political parties, publishing houses, religious organizations, unions or interest groups have no investment in The European.
The European in English
In October 2010, The European launched an English version of the magazine that is aimed at an international audience. It features debates on geopolitical i |
https://en.wikipedia.org/wiki/Radeon%20200%20series | The Radeon 200 series is a series of graphics processors developed by AMD. These GPUs are manufactured on a 28 nm Gate-Last process through TSMC or Common Platform Alliance.
Release
The Rx 200 series was announced on September 25, 2013, at the AMD GPU14 Tech Day event. Non-disclosure agreements were lifted on October 15, except for the R9 290X, and pre-orders opened on October 3.
Architecture
Graphics Core Next 3 (Volcanic Islands) is found on the R9 285 (Tonga Pro) branded products.
Graphics Core Next 2 (Sea Islands) is found on R7 260 (Bonaire), R7 260X (Bonaire XTX), R9 290 (Hawaii Pro), R9 290X (Hawaii XT), and R9 295X2 (Vesuvius) branded products.
Graphics Core Next 1 (Southern Islands) is found on R9 270, 270X, 280, 280X, R7 240, 250, 250X, 265, and R5 240 branded products.
TeraScale 2 (VLIW5) (Northern Islands or Evergreen) is found on R5 235X and below branded products.
OpenGL 4.x compliance requires supporting FP64 shaders. These are implemented by emulation on some TeraScale (microarchitecture) GPUs.
Vulkan 1.0 requires GCN-Architecture. Vulkan 1.1 requires GCN 2 or higher.
Multi-monitor support
The AMD Eyefinity-branded on-die display controllers were introduced in September 2009 in the Radeon HD 5000 Series and have been present in all products since.
AMD TrueAudio
AMD TrueAudio was introduced with the AMD Radeon Rx 200 Series, but can only be found on the dies of GCN 2/3 products.
Video acceleration
AMD's SIP core for video acceleration, Unified Video Decoder and Video Coding Engine, are found on all GPUs and supported by AMD Catalyst and by the free and open-source graphics device driver.
Use in cryptocurrency mining
During 2014 the Radeon R9 200 series GPUs offered a very competitive price for usage in cryptocurrency mining. This led to limited supply and huge price increases of up to 164% over the MSRP in Q4 of 2013 and Q1 of 2014. Since Q2 of 2018 availability of AMD GPUs as well as pricing has, in most cases, returned to normal.
Cros |
https://en.wikipedia.org/wiki/Cellulose%20acetate%20phthalate | Cellulose acetate phthalate (CAP), also known as cellacefate (INN) and cellulosi acetas phthalas, is a commonly used polymer phthalate in the formulation of pharmaceuticals, such as the enteric coating of tablets or capsules and for controlled release formulations. It is a cellulose polymer where about half of the hydroxyls are esterified with acetyls, a quarter are esterified with one or two carboxyls of a phthalic acid, and the remainder are unchanged. It is a hygroscopic white to off-white free-flowing powder, granules, or flakes. It is tasteless and odorless, though may have a weak odor of acetic acid. Its main use in pharmaceutics is with enteric formulations. It can be used together with other coating agents, e.g. ethyl cellulose. Cellulose acetate phthalate is commonly plasticized with diethyl phthalate, a hydrophobic compound, or triethyl citrate, a hydrophilic compound; other compatible plasticizers are various phthalates, triacetin, dibutyl tartrate, glycerol, propylene glycol, tripropionin, triacetin citrate, acetylated monoglycerides, etc.
Synthesis
The most common way to prepare cellulose acetate phthalate consists of the reaction of a partially substituted cellulose acetate (CA) with phthalic anhydride in the presence of an organic solvent and a basic catalyst. The organic solvents widely used as reaction media for the phthaloylation of cellulose acetate are acetic acid, acetone, or pyridine. The basic catalysts employed are anhydrous sodium acetate when using acetic acid, amines when using acetone, and the organic solvent itself when using pyridine as reaction medium.
Malm et al., records the preparation of phthalic acid derivatives of ethyl-cellulose and cellulose acetate without the use of pyridine by substituting sodium acetate as catalyst and acetic acid as a reaction solvent. Phthalyl content of the derivatives produced by this method is inversely dependent on the reaction temperature, although the rate of phthalyl introduction is faster at h |
https://en.wikipedia.org/wiki/Andreaea%20blyttii | Andreaea blyttii, also commonly known as Blytt's rock moss, is a moss belonging to the family Andreaeaceae, commonly known as rock moss, granite moss, or lantern moss because of this family's unique sporangium. It is part of the genus Andreaea which is known for forming dark brownish or reddish-black carpets in high elevations. This species was first described by Schimper in 1855.
Description
The shoots of A. blyttii vary in length. They are distinctively known for being small and dark red or black. They form tuffs and have acrocarpus growth. Depending on the frequency of desiccation, the branching pattern can vary from unbranched to irregularly branched. The number of leaves per shoot increases in dry environments. The stem walls are made up of pigmented cells and the stem lacks a conducting strand which is a character of the genus Andreaea. Rhizoids are attached at the base of the shoot. The spores are uniquely small in this species and grow into a thalloid protonema. The leaves of this species are known to vary in morphology. Leaf length and curvature, costa width and cell length are reduced in response to desiccation. Leaf curvature can be erect, falcate-secund, or curved. Larger more curved leaves with a smaller subula have been noted as a deviant morphology. Most leaves are erect and have a short and wide basal lamina with rectangular unistratose cells and a long subula also known as a limb with a costa spanning the entire length of the leaf. The costa is multistratose. This moss is closely related to Andreaea nivalis but A. blyttii lacks the denticulate leaf margins and very papillose upper cells of A. nivalis.
Habitat
Andreaea blyttii is usually found on rocks such as gneiss and granite. It also found in late to extremely late snow beds at low to high latitudes and elevations. It forms dense mats in mountain alpines where few other mosses can survive and is able to colonize sites of deglaciation. In Norway, it has commonly been observed growing in ass |
https://en.wikipedia.org/wiki/NHL%20repeat | The NHL repeat, named after ncl-1, HT2A and lin-41, is an amino acid sequence found largely in a large number of eukaryotic and prokaryotic proteins. For example, the repeat is found in a variety of enzymes of the copper type II, ascorbate-dependent monooxygenase family which catalyse the C-terminus alpha-amidation of biological peptides. In many it occurs in tandem arrays, for example in the RING finger beta-box, coiled-coil (RBCC) eukaryotic growth regulators. The arthropod 'Brain Tumor' protein (Brat; ) is one such growth regulator that contains a 6-bladed NHL-repeat beta-propeller.
The NHL repeats are also found in serine/threonine protein kinase (STPK) in diverse range of pathogenic bacteria. These STPK are transmembrane receptors with an intracellular N-terminal kinase domain and extracellular C-terminal sensor domain. In the STPK, PknD, from Mycobacterium tuberculosis, the sensor domain forms a rigid, six-bladed b-propeller composed of NHL repeats with a flexible tether to the transmembrane domain.
The NHL repeat has also been used to design a family of fully symmetrical 6-blade beta-propeller proteins called "Pizza". These proteins can also be engineered to bind mineral nanocrystals. |
https://en.wikipedia.org/wiki/Siam%207X | The Siam 7x is an Android dual-screen smartphone which launched in December 2015 and was designed by Darius Allen. This phone was the first phone produced by CRBT Siam, and the first dual-screen phone to be marketed to American consumers.
History
Several manufacturers, including Samsung, LG and Kyocera had made attempts to create a dual-screen smartphone. However, they proved unsuccessful as their second screens were located within a difficult to access clam-shell design. The Siam 7x overcame this by placing the second screen on the outside, using a black and white E Ink Corporation screen to conserve power. A similar design was created by Yotaphone but its parent company targeted this phone to European, Asian and Middle Eastern markets. The Siam 7x was the first dual-screen phone designed for the North American market.
The phone was available only with the Android operating system, and only as a GSM carrier phone. It allows users to insert two SIM cards simultaneously. The phone was designed in Dallas, and manufactured in Shenzhen, China.
Hardware
Processor: MTK6735A, Quad-Core Cortex A53
GPU: ARM MaliT760-MP3@450 MHz
Hard-drive: 1664GB
RAM: 2GB
Operating System: Android 5.1
Screen Size: 5.0" 1280 x 720 HD IPS 2.5D
Furthermore, the phone has a biometric ear print recognition system which employs the Descartes Bio-metric Helix system
Reception
The Siam 7x dual-screen smartphone was released to the public on November 27, 2015, (Black Friday). 10,000 of these phones were produced for its release date, targeting a relatively small sales volume. |
https://en.wikipedia.org/wiki/Ramaria%20araiospora | Ramaria araiospora, commonly known as the red coral, is a coral mushroom in the family Gomphaceae. First described in 1974, it is found in North America, and the Himalaya. An edible species, it is sold in local markets in Mexico.
Taxonomy
The species was first described scientifically by mycologists Currie Marr and Daniel Stuntz in their 1974 monograph, "Ramaria of western Washington". The holotype was collected in 1967 in Pierce County, Washington. Marr and Stuntz also published the variety rubella, which was originally collected in 1967 about south of Elbe, Washington. Ramaria araiospora is classified in the subgenus Laeticolora of Ramaria. The mushroom is commonly known as the "red coral".
Description
The fruit bodies of Ramaria araiospora typically measure tall by wide. There is a single, somewhat bulbous stipe measuring long by thick, which is branched up to six times. The branches are slender, usually about in diameter, while branches near the base are thicker, up to thick. The terminal branches are forked or finely divided into sharp tips. The context is fleshy to fibrous in young specimens, but becomes brittle when dried. The branches are red initially, fading to a lighter red in maturity, while the base, including the stipe, is white to yellowish-white. Branch tips are yellow. When dried, fruit bodies become yellowish white in the base and dull red in the branches. The fruit bodies have no distinctive taste or odor.
In deposit, the spores are white, cream, or yellowish. They are somewhat cylindrical, ornamented with lobed warts, and measure 9.9 by 3.7 μm. The basidia (spore-bearing cells) are club-shaped, one- to four-spored (although four spores is most typical), and have dimensions of 43–75 by 7–12 μm. The variety rubella differs from the main type in having slightly more "bluish or crimson" branches in mature specimens, and slightly smaller basidia that measure 30–70 by 6–10 μm.
Edibility
Ramaria araiospora fruit bodies are edible, but can |
https://en.wikipedia.org/wiki/Spy%20pixel | Spy pixels or tracker pixels are hyperlinks to remote image files in HTML email messages that have the effect of spying on the person reading the email if the image is downloaded. They are commonly embedded in the HTML of an email as small, imperceptible, transparent graphic files. Spy pixels are commonly used in marketing, and there are several countermeasures in place that aim to block email tracking pixels. However, there are few regulations in place that effectively guard against email tracking approaches.
History
Invented in 1971 by Ray Tomlinson, emails have made it much more convenient to send and receive messages as opposed to traditional postal mail. In 2020, there were 4 billion email users worldwide and approximately 306 billion emails sent and received daily. The email sender, however, still has to wait for a reply email from the recipient in order to confirm that their message was delivered. There are some situations where the recipient doesn't respond to the sender even when they have read the email, which is why the email tracking method emerged. Most email services do not provide indicators as to whether an email was read, so third-party applications and plug-ins have provided the convenience of email tracking. The most common method is the email tracking beacon or spy pixel.
Spy pixels were described as "endemic" in February 2021. The "Hey" email service, contacted by BBC News, estimated that it blocked spy pixels in about 600,000 out of 1,000,000 messages per day.
Mechanism
HTML email messages typically contain hyperlinks to online resources. Common software used by a recipient of email may, by default, automatically download remote image files from hyperlinks, without asking the user for confirmation. After downloading an image file, the software displays the image to the recipient. A spy pixel is an image file that is deliberately made small, often of a single pixel and of a colour that makes it "impossible to spot with the naked eye even if y |
https://en.wikipedia.org/wiki/List%20of%20human%20endocrine%20organs%20and%20actions |
Hypothalamic-pituitary axis
Hypothalamus
Pineal body (epiphysis)
Pituitary gland (hypophysis)
The pituitary gland (or hypophysis) is an endocrine gland about the size of a pea and weighing in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain, and rests in a small, bony cavity (sella turcica) covered by a dural fold (diaphragma sellae). The pituitary is functionally connected to the hypothalamus by the median eminence via a small tube called the infundibular stem or pituitary stalk. The anterior pituitary (adenohypophysis) is connected to the hypothalamus via the hypothalamo–hypophyseal portal vessels, which allows for quicker and more efficient communication between the hypothalamus and the pituitary.
Anterior pituitary lobe (adenohypophysis)
Posterior pituitary lobe (neurohypophysis)
Oxytocin and anti-diuretic hormone are not secreted in the posterior lobe, merely stored.
Thyroid
Digestive system
Stomach
Duodenum (small intestine)
Liver
Pancreas
The pancreas is a heterocrine gland as it functions both as an endocrine and as an exocrine gland.
Kidney
Adrenal glands
Adrenal cortex
Adrenal medulla
Reproductive
Testes
Ovarian follicle and corpus luteum
Placenta (when pregnant)
Uterus (when pregnant)
Calcium regulation
Parathyroid
Skin
Other
Heart
Bone
Skeletal muscle
In 1998, skeletal muscle was identified as an endocrine organ due to its now well-established role in the secretion of myokines. The use of the term myokine to describe cytokines and other peptides produced by muscle as signalling molecules was proposed in 2003.
Adipose tissue
Signalling molecules released by adipose tissue are referred to as adipokines. |
https://en.wikipedia.org/wiki/Lateral%20talocalcaneal%20ligament | The lateral talocalcaneal ligament (external calcaneo-astragaloid ligament) is a ligament in the ankle. It is a short, strong fasciculus, passing from the lateral surface of the talus, immediately beneath its fibular facet to the lateral surface of the calcaneus.
It is placed in front of, but on a deeper plane than, the calcaneofibular ligament, with the fibers of which it is parallel. |
https://en.wikipedia.org/wiki/E-patient | An e-patient is a health consumer who participates fully in his/her medical care, primarily by gathering information about medical conditions that impact them and their families, using the Internet and other digital tools. The term encompasses those who seek guidance for their own ailments and the friends and family members who go online on their behalf. E-patients report two effects of their health research: "better health information and services, and different, but not always better, relationships with their doctors."
E-patients are active in their care and demonstrate the power of the participatory medicine or Health 2.0 / Medicine 2.0. model of care. The "e" can stand for "electronic" but has also been used to refer to other terms, such as "equipped", "enabled", "empowered" and "expert".
The current state of knowledge on the impact of e-patients on the healthcare system and the quality of care received indicates:
A growing number of people say the internet played a crucial or important role as they helped another person cope with a major illness.
Many clinicians underestimated the benefits and overestimated the risks of online health resources for patients.
Medical online support groups are an important healthcare resource.
"the net friendliness of clinicians and provider organizations—as rated by the e-patients they serve—is becoming an important new aspect of healthcare quality."
According to one study, the advent of patients as partners is one of the most important cultural medical revolutions of the past century.
In order to understand the impact of the e-patient, clinicians will likely need to move beyond "pre-internet medical constructs".
Medical education must adapt to take the e-patient into account, and to prepare students for medical practice that includes the e-patient.
A 2011 study of European e-patients found that they tended to be "inquisitive and autonomous" and that they noted that the number of e-patients in Europe appeared to be rising. A |
https://en.wikipedia.org/wiki/Autonomy | In developmental psychology and moral, political, and bioethical philosophy, autonomy is the capacity to make an informed, uncoerced decision. Autonomous organizations or institutions are independent or self-governing. Autonomy can also be defined from a human resources perspective, where it denotes a (relatively high) level of discretion granted to an employee in his or her work. In such cases, autonomy is known to generally increase job satisfaction. Self-actualized individuals are thought to operate autonomously of external expectations. In a medical context, respect for a patient's personal autonomy is considered one of many fundamental ethical principles in medicine.
Sociology
In the sociology of knowledge, a controversy over the boundaries of autonomy inhibited analysis of any concept beyond relative autonomy, until a typology of autonomy was created and developed within science and technology studies. According to it, the institution of science's existing autonomy is "reflexive autonomy": actors and structures within the scientific field are able to translate or to reflect diverse themes presented by social and political fields, as well as influence them regarding the thematic choices on research projects.
Institutional autonomy
Institutional autonomy is having the capacity as a legislator to be able to implant and pursue official goals. Autonomous institutions are responsible for finding sufficient resources or modifying their plans, programs, courses, responsibilities, and services accordingly. But in doing so, they must contend with any obstacles that can occur, such as social pressure against cut-backs or socioeconomic difficulties. From a legislator's point of view, to increase institutional autonomy, conditions of self-management and institutional self-governance must be put in place. An increase in leadership and a redistribution of decision-making responsibilities would be beneficial to the research of resources.
Institutional autonomy was often |
https://en.wikipedia.org/wiki/Living%20Earth%20Simulator%20Project | The Living Earth simulator is a proposed massive computer simulation system intended to simulate the interactions of all aspects of life, human economic activity, climate, and other physical processes on the planet Earth as part of the FuturICT project, in response to the European FP7 "Future and Emerging Technologies Flagship" initiative.
The Future and Emerging Technologies 'flagship' competition offered a 10-years, ~€1 billion funding to the winning teams; the competition attracted over 300 international teams.
The FuturICT project was not selected and thus the Living Earth Simulator was never developed. The two winners, announced as of March 2013, were Graphene and Human Brain. |
https://en.wikipedia.org/wiki/MiMedx | MiMedx Group is a biomedical company based in Marietta, Georgia, founded in 2008. It is traded on the NASDAQ as MDXG. The CEO is Tim Wright. Using tissues from birth such as the placenta, amniotic sac, and umbilical cord, MiMedx creates skin for skin grafts.
With the arrival of Wright in May 2019, the company accelerated the process of working with auditors and regulators to resolve legal and financial issues created by the previous management (see ‘History’). Wright also began a cultural and financial turnaround, assembling a new senior management team by August 2019 to instill “transparency, truthfulness, and timeliness” in communications and business dealings. As of December 2020, the company had approximately 735 employees.
By August 2020, MiMedx had raised $150 million in concurrent private equity and debt financings; completed a required financial restatement; and filed its 2019 annual report and 2020 first-quarter report.
MiMedx's application to relist its common stock on the NASDAQ was approved on October 30, 2020. The company had been delisted from the NASDAQ in November 2018 and had traded on OTC Pink until relisting.
As of November 2020, MiMedx had supplied more than two million allografts for skin grafts to address persistent wounds such as diabetic foot ulcers that often result in amputation, burns, and other urgent health issues.
History
In 2008, Parker H. Petit, who formed Life Systems in the 1970s, founded MiMedx and became CEO in 2009. Life Systems went public as Healthdyne Inc. in 1981. Healthdyne split into multiple companies, one of which became Matria Healthcare and Petit was named CEO in 2000. He retired from Matria in 2008 when it was acquired by Alere. MiMedx joined the NASDAQ exchange in April 2012 as MDXG. The company's 2012 revenue was around $27 million and MiMedx was named one of Fortune's fastest-growing companies in 2017. MXDG was delisted in November 2018 after fraud and other impropriety and began trading on OTC Pink. Motley Fool |
https://en.wikipedia.org/wiki/Technetium-99m | Technetium-99m (99mTc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99mTc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical radioisotope in the world.
Technetium-99m is used as a radioactive tracer and can be detected in the body by medical equipment (gamma cameras). It is well suited to the role, because it emits readily detectable gamma rays with a photon energy of 140 keV (these 8.8 pm photons are about the same wavelength as emitted by conventional X-ray diagnostic equipment) and its half-life for gamma emission is 6.0058 hours (meaning 93.7% of it decays to 99Tc in 24 hours). The relatively "short" physical half-life of the isotope and its biological half-life of 1 day (in terms of human activity and metabolism) allows for scanning procedures which collect data rapidly but keep total patient radiation exposure low. The same characteristics make the isotope unsuitable for therapeutic use.
Technetium-99m was discovered as a product of cyclotron bombardment of molybdenum. This procedure produced molybdenum-99, a radionuclide with a longer half-life (2.75 days), which decays to 99mTc. This longer decay time allows for 99Mo to be shipped to medical facilities, where 99mTc is extracted from the sample as it is produced. In turn, 99Mo is usually created commercially by fission of highly enriched uranium in a small number of research and material testing nuclear reactors in several countries.
History
Discovery
In 1938, Emilio Segrè and Glenn T. Seaborg isolated for the first time the metastable isotope technetium-99m, after bombarding natural molybdenum with 8 MeV deuterons in the cyclotron of Ernest Orlando Lawrence's Radiation laboratory. In 1970 Seaborg explained that:
Later in 1940, Emilio Segrè and Chien-Shiung Wu published experimental results of an analysis of fission products of uranium-235, including molybdenum-99, and detected the pres |
https://en.wikipedia.org/wiki/Dark%20flow | In astrophysics, dark flow is a theoretical non-random component of the peculiar velocity of galaxy clusters. The actual measured velocity is the sum of the velocity predicted by Hubble's Law plus a possible small and unexplained (or dark) velocity flowing in a common direction.
According to standard cosmological models, the motion of galaxy clusters with respect to the cosmic microwave background should be randomly distributed in all directions. However, analyzing the three-year Wilkinson Microwave Anisotropy Probe (WMAP) data using the kinematic Sunyaev–Zeldovich effect, a team of astronomers lead by Alexander Kashlinsky found evidence of a "surprisingly coherent" 600–1000 km/s flow of clusters toward a 20-degree patch of sky between the constellations of Centaurus and Vela.
The researchers had suggested that the motion may be a remnant of the influence of no-longer-visible regions of the universe prior to inflation. Telescopes cannot see events earlier than about 380,000 years after the Big Bang, when the universe became transparent (the cosmic microwave background); this corresponds to the particle horizon at a distance of about 46 billion (4.6×10) light years. Since the matter causing the net motion in this proposal is outside this range, it would in a certain sense be outside our visible universe; however, it would still be in our past light cone.
The results appeared in the October 20, 2008, issue of Astrophysical Journal Letters.
In 2013, data from the Planck space telescope showed no evidence of "dark flow" on that sort of scale, discounting the claims of evidence for either gravitational effects reaching beyond the visible universe or existence of a multiverse. However, in 2015 Atrio-Barandela et al. claim to have found support for its existence using both Planck and WMAP data. The paper stated that a more complete analysis was in preparation to exploit the full Planck cluster sample to further build evidence, however the team have published no further |
https://en.wikipedia.org/wiki/Telalginite | Telalginite is a structured organic matter (alginite) in sapropel, composed of large discretely occurring colonial or thick-walled unicellular algae such as Botryococcus, Tasmanites and Gloeocapsomorpha prisca. Telalginite is present in large algal bodies. It fluoresce brightly in shades of yellow under blue/ultraviolet light. The term of telalginite was introduced by Adrian C. Hutton of the University of Wollongong.
See also
Lamalginite |
https://en.wikipedia.org/wiki/3-Phosphoglyceric%20acid | 3-Phosphoglyceric acid (3PG, 3-PGA, or PGA) is the conjugate acid of 3-phosphoglycerate or glycerate 3-phosphate (GP or G3P). This glycerate is a biochemically significant metabolic intermediate in both glycolysis and the Calvin-Benson cycle. The anion is often termed as PGA when referring to the Calvin-Benson cycle. In the Calvin-Benson cycle, 3-phosphoglycerate is typically the product of the spontaneous scission of an unstable 6-carbon intermediate formed upon CO2 fixation. Thus, two equivalents of 3-phosphoglycerate are produced for each molecule of CO2 that is fixed. In glycolysis, 3-phosphoglycerate is an intermediate following the dephosphorylation (reduction) of 1,3-bisphosphoglycerate.
Glycolysis
In the glycolytic pathway, 1,3-bisphosphoglycerate is dephosphorylated to form 3-phosphoglyceric acid in a coupled reaction producing two ATP via substrate-level phosphorylation. The single phosphate group left on the 3-PGA molecule then moves from an end carbon to a central carbon, producing 2-phosphoglycerate. This phosphate group relocation is catalyzed by phosphoglycerate mutase, an enzyme that also catalyzes the reverse reaction.
Calvin-Benson cycle
In the light-independent reactions (also known as the Calvin-Benson cycle), two 3-phosphoglycerate molecules are synthesized. RuBP, a 5-carbon sugar, undergoes carbon fixation, catalyzed by the rubisco enzyme, to become an unstable 6-carbon intermediate. This intermediate is then cleaved into two, separate 3-carbon molecules of 3-PGA. One of the resultant 3-PGA molecules continues through the Calvin-Benson cycle to be regenerated into RuBP while the other is reduced to form one molecule of glyceraldehyde 3-phosphate (G3P) in two steps: the phosphorylation of 3-PGA into 1,3-bisphosphoglyceric acid via the enzyme phosphoglycerate kinase (the reverse of the reaction seen in glycolysis) and the subsequent catalysis by glyceraldehyde 3-phosphate dehydrogenase into G3P. G3P eventually reacts to form the sugars such |
https://en.wikipedia.org/wiki/MusicMaster%20%28software%29 | MusicMaster is a music scheduling software produced by A-Ware Software (aka MusicMaster, Inc. of Dallas, Texas USA) and used by radio, Internet and television stations. Their main office is located in Dallas, Texas.
History
MusicMaster was created in 1983 by Joseph Knapp, an engineer, radio programmer and on-air personality for several stations in Ohio and Wisconsin, United States. Knapp believed that the decision-making process of selecting music for airplay could best be done using computers. In 1983, Knapp began writing a program he called Revolve, meant to improve the rotation of songs for airplay. Previously, music scheduling had been done by hand, as disc jockeys selected a song card from the front of a stack, played the track, and returned the card to the back of the stack to ensure that it was equally rotated with all available songs. With the use of computers, better decisions could be made based on a set of programmable rules. For instance, the rule of artist separation would ensure that two songs by the same artist needed to be separated by a given amount of time.
After selling the first copy of MusicMaster to WCXI-FM/Detroit, Knapp rewrote the program for the Radio Shack TRS-80 and then for the IBM PC. By 1985, it was licensed for distribution by Tapscan and sold as MusicScan. When a legal dispute ended A-ware's relationship with Tapscan in 1994, Knapp formed his own company and distributed the program as MusicMaster. In 2001, MusicMaster was ported to Microsoft Windows.
Overview
The heart of MusicMaster is a music database, which is custom built to the user's specifications. This database can include information such as song title, artist, trivia, and any other information the user needs to identify each song. The users can also add attributes to each song to identify the type, era, tempo, mood and other factors that will be used by MusicMaster to control the flow, balance and mix of the scheduled playlists using scheduling rules. The user creates ru |
https://en.wikipedia.org/wiki/National%20Interagency%20Confederation%20for%20Biological%20Research | The National Interagency Confederation for Biological Research (NICBR, pronounced "Nick Burr") is a biotechnology and biodefense partnership and collaborative environment of eight U.S. Federal government agencies at Fort Detrick, Maryland, US.
Structure
Four federal cabinet level departments are represented in the NICBR: The DoD (2 agencies), the DHHS (4), the DHS (1) and the USDA (1). The NICBR agencies are:
U.S. Army Medical Research and Materiel Command (USAMRMC), DoD
National Institute of Allergy and Infectious Diseases (NIAID), DHHS
National Cancer Institute (NCI), DHHS
Agricultural Research Service, USDA
DHS Science and Technology Directorate, DHS
Centers for Disease Control and Prevention (CDC), DHHS
Naval Medical Research Center (NMRC), DoD
U.S. Food and Drug Administration (FDA), DHHS
Some NICBR laboratories are physically consolidated on the National Interagency Biodefense Campus (NIBC) which includes all NICBR partners except NCI, which maintains its own campus on the Rosemont Avenue side of Fort Detrick. The Fort Detrick Interagency Coordinating Committee (FDICC) is the central hub of the NICBR governance structure, which is chaired by the Fort Detrick U.S. Army garrison commander. It is composed of all NICBR partner representatives.
Leadership and personnel
The FDICC meets twice a month and reports to the Executive Steering Committee (ESC), which is chaired by the commander, U. S. Army Medical Research and Materiel Command and is composed of equivalents across the partner agencies. The ESC reports to the NICBR Board of Directors (BOD), consisting of the chair, currently Army Surgeon General, and her equivalents across the partnership. Collectively, the NICBR governance bodies provide strategic direction and oversight.
Working groups and subcommittees
Reporting to the FDICC are seven subcommittees and three working groups:
The Sustainment Subcommittee
The Financial and Business Planning Subcommittee
The Public Affairs and Community Rel |
https://en.wikipedia.org/wiki/JAD%20%28software%29 | Jad (Java Decompiler) is, , an unmaintained decompiler for the Java programming language.
Jad provides a command-line user interface to extract source code from class files.
See also
Java Decompiler
Mocha |
https://en.wikipedia.org/wiki/Bank%20switching | Bank switching is a technique used in computer design to increase the amount of usable memory beyond the amount directly addressable by the processor instructions. It can be used to configure a system differently at different times; for example, a ROM required to start a system from diskette could be switched out when no longer needed. In video game systems, bank switching allowed larger games to be developed for play on existing consoles.
Bank switching originated in minicomputer systems. Many modern microcontrollers and microprocessors use bank switching to manage random-access memory, non-volatile memory, input-output devices and system management registers in small embedded systems. The technique was common in 8-bit microcomputer systems. Bank-switching may also be used to work around limitations in address bus width, where some hardware constraint prevents straightforward addition of more address lines, and to work around limitations in the ISA, where the addresses generated are narrower than the address bus width. Some control-oriented microprocessors use a bank-switching technique to access internal I/O and control registers, which limits the number of register address bits that must be used in every instruction.
Unlike memory management by paging, data is not exchanged with a mass storage device like disk storage. Data remains in quiescent storage in a memory area that is not currently accessible to the processor (although it may be accessible to the video display, DMA controller, or other subsystems of the computer) without the use of special prefix instructions.
Technique
Bank switching can be considered as a way of extending the address space of processor instructions with some register. Examples:
The follow-on system to a processor with a 12 bit address has a 15 bit address bus, but there is no way to directly specify the high three bits on the address bus. Internal bank registers can be used to provide those bits.
The follow-on system to a processor |
https://en.wikipedia.org/wiki/Palmtop%20PC | A Palmtop PC was an approximately pocket calculator-sized, battery-powered computer compatible with the IBM Personal Computer in a horizontal clamshell design with integrated keyboard and display. It could be used like a subnotebook, but was light enough to be comfortably used handheld as well. Most Palmtop PCs were small enough to be stored in a user's shirt or jacket pockets.
Palmtop PCs distinguish from other palmtop computers by using a mostly IBM-compatible PC architecture and BIOS as well as an Intel-compatible x86 processor. All such devices were DOS-based, with DOS stored in ROM. While many Palmtop PCs came with a number of PDA and office applications pre-installed in ROM, most of them could also run generic, off-the-shelf PC software with no or little modifications. Some could also run other operating systems such as GEOS, Windows 1.0-3.0 (in Real mode only), or MINIX 2.0.
Most Palmtop PCs were based on a static hardware design for low power consumption and instant-on/off without the need to reboot. Depending on the model, the battery could power the device for a period ranging from several hours up to several days while running, or between a week and a year in standby mode. Combined with the instant-on/off feature, a battery would typically last from a week up to several months in practical use as PDA.
The first Palmtop PC was the DIP Pocket PC (aka Atari Portfolio) in 1989.
Palmtop PCs include:
DIP Pocket PC (DIP DOS 2.11, 1989)
Atari Portfolio (DIP DOS 2.11, 1989)
Poqet PC Classic (MS-DOS 3.3, 80C88, 1989)
Poqet PC Prime (MS-DOS 3.3, 80C88)
Poqet PC Plus (MS-DOS 5.0, NEC V30)
ZEOS Pocket PC (MS-DOS 5.0, 1991)
Sharp PC-3000 (MS-DOS 3.3, 1991)
Sharp PC-3100 (MS-DOS 3.3, 1991)
Hewlett-Packard 95LX (MS-DOS 3.22, NEC V20, 1991)
Hewlett-Packard 100LX (MS-DOS 5.0, 80186-compatible HP Hornet, 1993)
Hewlett-Packard Palmtop FX (MS-DOS 5.0, 80186-compatible HP Hornet, 1993)
Hewlett-Packard 200LX (MS-DOS 5.0, 80186-compatible HP Hornet, 1994)
Hewlett-Packard 10 |
https://en.wikipedia.org/wiki/Cap%20product | In algebraic topology the cap product is a method of adjoining a chain of degree p with a cochain of degree q, such that q ≤ p, to form a composite chain of degree p − q. It was introduced by Eduard Čech in 1936, and independently by Hassler Whitney in 1938.
Definition
Let X be a topological space and R a coefficient ring. The cap product is a bilinear map on singular homology and cohomology
defined by contracting a singular chain with a singular cochain by the formula:
Here, the notation indicates the restriction of the simplicial map to its face spanned by the vectors of the base, see Simplex.
Interpretation
In analogy with the interpretation of the cup product in terms of the Künneth formula, we can explain the existence of the cap product in the following way. Using CW approximation we may assume that is a CW-complex and (and ) is the complex of its cellular chains (or cochains, respectively). Consider then the composition
where we are taking tensor products of chain complexes, is the diagonal map which induces the map
on the chain complex, and is the evaluation map (always 0 except for ).
This composition then passes to the quotient to define the cap product , and looking carefully at the above composition shows that it indeed takes the form of maps , which is always zero for .
Fundamental Class
For any point in , we have the long-exact sequence in homology (with coefficients in ) of the pair (M, M - {x}) (See Relative homology)
An element of is called the fundamental class for if is a generator of . A fundamental class of exists if is closed and R-orientable. In fact, if is a closed, connected and -orientable manifold, the map is an isomorphism for all in and hence, we can choose any generator of as the fundamental class.
Relation with Poincaré duality
For a closed -orientable n-manifold with fundamental class in (which we can choose to be any generator of ), the cap product map
is an isomorphism for all . This result i |
https://en.wikipedia.org/wiki/National%20Centers%20for%20Environmental%20Information | The National Centers for Environmental Information (NCEI) is a U.S. government agency that manages one of the world’s largest archives of atmospheric, coastal, geophysical, and oceanic data. The current director is Derek Arndt.
NCEI is operated by the National Environmental Satellite, Data, and Information Service (NESDIS), an office of the National Oceanic and Atmospheric Administration (NOAA), which operates under the U.S. Department of Commerce.
In addition to archiving data, NCEI develops products and services that make data readily available to scientists, government officials, the business community, academia, non-governmental organizations, and the general public.
NCEI provides environmental data, products, and services covering the depths of the ocean to the surface of the Sun.
History
NCEI was created in 2015 from the merger of three NOAA data centers:
National Climatic Data Center (NCDC)
National Geophysical Data Center (NGDC)
National Oceanographic Data Center (NODC), which includes the National Coastal Data Development Center (NCDDC)
NCEI was established by the in Consolidated and Further Continuing Appropriations Act, 2015, Public Law 113-235 response to increasing demand for environmental information. The organization was created by merging existing National Data Centers for Weather and Climate, Oceans, Coasts, and Geophysics with the goal of streamlining the collection and preservation of environmental data.
The merger, which came in response to increasing demand for environmental information, was intended to make NOAA's data more useful through the application of consistent data stewardship practices across all science disciplines. NCEI works with the ISC World Data System to make data free and accessible.
Data and services
The NCEI archive contains more than 60 petabytes of data, equivalent to more than 700 million filing cabinets filled with documents. NCEI offers users access to tens of thousands of datasets and hundreds of products. |
https://en.wikipedia.org/wiki/Slewing | Slewing is the rotation of an object around an axis, usually the z axis. An example is a radar scanning 360 degrees by slewing around the z axis. This is also common terminology in astronomy. The process of rotating a telescope to observe a different region of the sky is referred to as slewing.
The term slewing is also found in motion control applications. Often the slew axis is combined with another axis to form a motion profile.
In crane terminology, slewing is the angular movement of a crane boom or crane jib in a horizontal plane.
The term is also used in the computer game Microsoft Flight Simulator wherein the user presses a key and he or she can rotate and move the virtual aircraft along all three spatial planes.
In the modern day use of CNC programs, slewing is a vital part of the process.
Mechanics |
https://en.wikipedia.org/wiki/Australian%20wormy%20chestnut | Australian wormy chestnut or firestreak is a common name for lumber of Eucalyptus obliqua, Eucalyptus sieberi and Eucalyptus fastigata grown in Victoria, southern New South Wales, and Tasmania in Australia. It is a hardwood species commonly used in flooring applications. |
https://en.wikipedia.org/wiki/Gauge%20group%20%28mathematics%29 | A gauge group is a group of gauge symmetries of the Yang–Mills gauge theory of principal connections on a principal bundle. Given a principal bundle with a structure Lie group , a gauge group is defined to be a group of its vertical automorphisms. This group is isomorphic to the group of global sections of the associated group bundle whose typical fiber is a group which acts on itself by the adjoint representation. The unit element of is a constant unit-valued section of .
At the same time, gauge gravitation theory exemplifies field theory on a principal frame bundle whose gauge symmetries are general covariant transformations which are not elements of a gauge group.
In the physical literature on gauge theory, a structure group of a principal bundle often is called the gauge group.
In quantum gauge theory, one considers a normal subgroup of a gauge group which is the stabilizer
of some point of a group bundle . It is called the pointed gauge group. This group acts freely on a space of principal connections. Obviously, . One also introduces the effective gauge group where is the center of a gauge group . This group acts freely on a space of irreducible principal connections.
If a structure group is a complex semisimple matrix group, the Sobolev completion of a gauge group can be introduced. It is a Lie group. A key point is that the action of on a Sobolev completion of a space of principal connections is smooth, and that an orbit space is a Hilbert space. It is a configuration space of quantum gauge theory. |
https://en.wikipedia.org/wiki/Spectral%20dimension | The spectral dimension is a real-valued quantity that characterizes a spacetime geometry and topology. It characterizes a spread into space over time, e.g. a ink drop diffusing in a water glass or the evolution of a pandemic in a population. Its definition is as follow: if a phenomenon spreads as , with the time, then the spectral dimension is . The spectral dimension depends on the topology of the space, e.g., the distribution of neighbors in a population, and the diffusion rate.
In physics, the concept of spectral dimension is used, among other things, in
quantum gravity,
percolation theory,
superstring theory, or
quantum field theory.
Examples
The diffusion of ink in an isotropic homogeneous medium like still water evolves as , giving a spectral dimension of 3.
Ink in a 2D Sierpiński triangle diffuses following a more complicated path and thus more slowly, as , giving a spectral dimension of 1.3652.
See also
Dimension
Fractal dimension
Hausdorff dimension |
https://en.wikipedia.org/wiki/Harmonic%20pitch%20class%20profiles | Harmonic pitch class profiles (HPCP) is a group of features that a computer program extracts from an audio signal, based on a pitch class profile—a descriptor proposed in the context of a chord recognition system. HPCP are an enhanced pitch distribution feature that are sequences of feature vectors that, to a certain extent, describe tonality, measuring the relative intensity of each of the 12 pitch classes of the equal-tempered scale within an analysis frame. Often, the twelve pitch spelling attributes are also referred to as chroma and the HPCP features are closely related to what is called chroma features or chromagrams.
By processing musical signals, software can identify HPCP features and use them to estimate the key of a piece, to measure similarity between two musical pieces (cover version identification), to perform content-based audio retrieval (audio matching),
to extract the musical structure (audio structure analysis),
and to classify music in terms of composer, genre or mood. The process is related to time-frequency analysis. In general, chroma features are robust to noise (e.g., ambient noise or percussive sounds), independent of timbre and instrumentation and independent of loudness and dynamics.
HPCPs are tuning independent and consider the presence of harmonic frequencies, so that the reference frequency can be different from the standard A 440 Hz. The result of HPCP computation is a 12, 24, or 36-bin octave-independent histogram depending on the desired resolution, representing the relative intensity of each 1, 1/2, or 1/3 of the 12 semitones of the equal tempered scale.
General HPCP feature extraction procedure
The block diagram of the procedure is shown in Fig.1 and is further detailed in.
The General HPCP feature extraction procedure is summarized as follows:
Input musical signal.
Do spectral analysis to obtain the frequency components of the music signal.
Use Fourier transform to convert the signal into a spectrogram. (The Fourier transfor |
https://en.wikipedia.org/wiki/Weyl%27s%20lemma%20%28Laplace%20equation%29 | In mathematics, Weyl's lemma, named after Hermann Weyl, states that every weak solution of Laplace's equation is a smooth solution. This contrasts with the wave equation, for example, which has weak solutions that are not smooth solutions. Weyl's lemma is a special case of elliptic or hypoelliptic regularity.
Statement of the lemma
Let be an open subset of -dimensional Euclidean space , and let denote the usual Laplace operator. Weyl's lemma states that if a locally integrable function is a weak solution of Laplace's equation, in the sense that
for every smooth test function with compact support, then (up to redefinition on a set of measure zero) is smooth and satisfies pointwise in .
This result implies the interior regularity of harmonic functions in , but it does not say anything about their regularity on the boundary .
Idea of the proof
To prove Weyl's lemma, one convolves the function with an appropriate mollifier and shows that the mollification satisfies Laplace's equation, which implies that has the mean value property. Taking the limit as and using the properties of mollifiers, one finds that also has the mean value property, which implies that it is a smooth solution of Laplace's equation. Alternative proofs use the smoothness of the fundamental solution of the Laplacian or suitable a priori elliptic estimates.
Generalization to distributions
More generally, the same result holds for every distributional solution of Laplace's equation: If satisfies for every , then is a regular distribution associated with a smooth solution of Laplace's equation.
Connection with hypoellipticity
Weyl's lemma follows from more general results concerning the regularity properties of elliptic or hypoelliptic operators. A linear partial differential operator with smooth coefficients is hypoelliptic if the singular support of is equal to the singular support of for every distribution . The Laplace operator is hypoelliptic, so if , then the sing |
https://en.wikipedia.org/wiki/Optical%20lattice | An optical lattice is formed by the interference of counter-propagating laser beams, creating a spatially periodic polarization pattern. The resulting periodic potential may trap neutral atoms via the Stark shift. Atoms are cooled and congregate at the potential extrema (at maxima for blue-detuned lattices, and minima for red-detuned lattices). The resulting arrangement of trapped atoms resembles a crystal lattice and can be used for quantum simulation.
Atoms trapped in the optical lattice may move due to quantum tunneling, even if the potential well depth of the lattice points exceeds the kinetic energy of the atoms, which is similar to the electrons in a conductor. However, a superfluid–Mott insulator transition may occur, if the interaction energy between the atoms becomes larger than the hopping energy when the well depth is very large. In the Mott insulator phase, atoms will be trapped in the potential minima and cannot move freely, which is similar to the electrons in an insulator. In the case of Fermionic atoms, if the well depth is further increased the atoms are predicted to form an antiferromagnetic, i.e. Néel state at sufficiently low temperatures.
Parameters
There are two important parameters of an optical lattice: the potential well depth and the periodicity.
Control of potential depth
The potential experienced by the atoms is related to the intensity of the laser used to generate the optical lattice. The potential depth of the optical lattice can be tuned in real time by changing the power of the laser, which is normally controlled by an acousto-optic modulator (AOM). The AOM is tuned to deflect a variable amount of the laser power into the optical lattice. Active power stabilization of the lattice laser can be accomplished by feedback of a photodiode signal to the AOM.
Control of periodicity
The periodicity of the optical lattice can be tuned by changing the wavelength of the laser or by changing the relative angle between the two laser beams. |
https://en.wikipedia.org/wiki/Negative-feedback%20amplifier | A negative-feedback amplifier (or feedback amplifier) is an electronic amplifier that subtracts a fraction of its output from its input, so that negative feedback opposes the original signal. The applied negative feedback can improve its performance (gain stability, linearity, frequency response, step response) and reduces sensitivity to parameter variations due to manufacturing or environment. Because of these advantages, many amplifiers and control systems use negative feedback.
An idealized negative-feedback amplifier as shown in the diagram is a system of three elements (see Figure 1):
an amplifier with gain AOL,
a feedback network β, which senses the output signal and possibly transforms it in some way (for example by attenuating or filtering it),
a summing circuit that acts as a subtractor (the circle in the figure), which combines the input and the transformed output.
Overview
Fundamentally, all electronic devices that provide power gain (e.g., vacuum tubes, bipolar transistors, MOS transistors) are nonlinear. Negative feedback trades gain for higher linearity (reducing distortion) and can provide other benefits. If not designed correctly, amplifiers with negative feedback can under some circumstances become unstable due to the feedback becoming positive, resulting in unwanted behavior such as oscillation. The Nyquist stability criterion developed by Harry Nyquist of Bell Laboratories is used to study the stability of feedback amplifiers.
Feedback amplifiers share these properties:
Pros:
Can increase or decrease input impedance (depending on type of feedback).
Can increase or decrease output impedance (depending on type of feedback).
Reduces total distortion if sufficiently applied (increases linearity).
Increases the bandwidth.
Desensitizes gain to component variations.
Can control step response of amplifier.
Cons:
May lead to instability if not designed carefully.
Amplifier gain decreases.
Input and output impedances of a negative-feedba |
https://en.wikipedia.org/wiki/Suspension%20array%20technology | Suspension array technology (or SAT) is a high throughput, large-scale, and multiplexed screening platform used in molecular biology. SAT has been widely applied to genomic and proteomic research, such as single nucleotide polymorphism (SNP) genotyping, genetic disease screening, gene expression profiling, screening drug discovery and clinical diagnosis. SAT uses microsphere beads (5.6 um in diameter) to prepare arrays. SAT allows for the simultaneous testing of multiple gene variants through the use of these microsphere beads as each type of microsphere bead has a unique identification based on variations in optical properties, most common is fluorescent colour. As each colour and intensity of colour has a unique wavelength, beads can easily be differentiated based on their wavelength intensity. Microspheres are readily suspendable in solution and exhibit favorable kinetics during an assay. Similar to flat microarrays (e.g. DNA microarray), an appropriate receptor molecule, such as DNA oligonucleotide probes, antibodies, or other proteins, attach themselves to the differently labeled microspheres. This produces thousands of microsphere array elements. Probe-target hybridization is usually detected by optically labeled targets, which determines the relative abundance of each target in the sample.
Overview of SAT using DNA hybridization
DNA is extracted from cells used to create test fragments. These test fragments are added to a solution containing a variety of microsphere beads. Each type of microsphere bead contains a known DNA probe with a unique fluorescent identity. Test fragments and probes on the microsphere beads are allowed to hybridize to each other. Once hybridized, the microsphere beads are sorted, usually using flow cytometry. This allows for the detection of each of the gene variants from the original sample. The resulting data collected will indicate the relative abundance of each hybridized sample to the microsphere.
Multiplexing
Since microsphere |
https://en.wikipedia.org/wiki/Wylie%20Dufresne | Wylie Dufresne (born 1970) is the chef and owner of Du's Donuts and the former chef and owner of the wd~50 and Alder restaurants in Manhattan. Dufresne is a leading American proponent of molecular gastronomy, the movement to incorporate science and new techniques in the preparation and presentation of food.
Early life
Born in 1970 in Providence, Rhode Island, Dufresne is a graduate of Friends Seminary and The French Culinary Institute (now known as The International Culinary Center) in New York. In 1992, he completed a B.A. in philosophy at Colby College in Waterville, Maine.
Career
From 1994 through 1999, he worked for Jean-Georges Vongerichten, where he was eventually named sous chef at Vongerichten's eponymous Jean Georges. In 1998 he was chef de cuisine at Vongerichten's Prime in The Bellagio, Las Vegas. In 1999, he left to become the first chef at 71 Clinton Fresh Food. In April 2003, he opened his 70-seat restaurant, wd~50 (named for the chef's initials and the street address, as well as a pun on WD-40) on Clinton Street on Manhattan's Lower East Side. In March 2013, he opened a second restaurant Alder in the East Village. wd-50 closed 30 November 2014 and Alder closed in August 2015.
Dufresne was a James Beard Foundation nominee for Rising Star Chef of the Year in 2000 and chosen the same year by New York Magazine for their New York Awards. Food & Wine magazine named him one of 2001 America's Ten Best Chefs award and, in 2006, New York Magazine's Adam Platt placed wd-50 fourth in his list of New York's 101 best restaurants. He was awarded a star in Michelin's New York City Guide, 2006, 2007, and 2008, the first Red Guide for North America, and was nominated for Best Chef New York by the James Beard Foundation. His signature preparations include Pickled Beef Tongue with Fried Mayonnaise and Carrot-Coconut Sunnyside-Up.
In 2006, Dufresne lost to Mario Batali on Iron Chef America. In 2007, he began making appearances as a judge on Bravo's Top Chef, which in |
https://en.wikipedia.org/wiki/Sustentacular%20cell | A sustentacular cell is a type of cell primarily associated with structural support, they can be found in various tissues.
Sustentacular cells of the olfactory epithelium (also called supporting cells or Sertoli cells) have been shown to be involved in the phagocytosis of dead neurons, odorant transformation and xenobiotic metabolism.
One type of sustentacular cell is the Sertoli cell, in the testicle. It is located in the walls of the seminiferous tubules and supplies nutrients to sperm. They are responsible for the differentiation of spermatids, the maintenance of the blood-testis barrier, and the secretion of inhibin, androgen-binding protein and Mullerian-inhibiting factor.
The organ of Corti in the inner ear and taste buds also contain sustentacular cells.
Another type of sustentacular cell is found with glomus cells of the carotid and aortic bodies.
About 40% of carcinoids have a scattering of sustentacular cells, which stain positive for S-100. |
https://en.wikipedia.org/wiki/Proof%20of%20space | Proof of space (PoS) is a type of consensus algorithm achieved by demonstrating one's legitimate interest in a service (such as sending an email) by allocating a non-trivial amount of memory or disk space to solve a challenge presented by the service provider. The concept was formulated in 2013 by Dziembowski et al. and (with a different formulation) by Ateniese et al..
Proofs of space are very similar to proofs of work (PoW), except that instead of computation, storage is used to earn cryptocurrency. Proof-of-space is different from memory-hard functions in that the bottleneck is not in the number of memory access events, but in the amount of memory required.
After the release of Bitcoin, alternatives to its PoW mining mechanism were researched, and PoS was studied in the context of cryptocurrencies. Proofs of space are seen as a fairer and greener alternative by blockchain enthusiasts due to the general-purpose nature of storage and the lower energy cost required by storage.
In 2014, Signum (formerly Burstcoin) became the first practical implementation of a PoS (initially as proof of capacity) blockchain technology and is still actively developed. Other than Signum, several theoretical and practical implementations of PoS have been released and discussed, such as SpaceMint and Chia, but some were criticized for increasing demand and shortening the life of storage devices due to greater disc reading requirements than Signum.
Concept description
A proof-of-space is a piece of data that a prover sends to a verifier to prove that the prover has reserved a certain amount of space. For practicality, the verification process needs to be efficient, namely, consume a small amount of space and time. For security, it should be hard for the prover to pass the verification if it does not actually reserve the claimed amount of space.
One way of implementing PoS is by using hard-to-pebble graphs. The verifier asks the prover to build a labeling of a hard-to-pebble graph. Th |
https://en.wikipedia.org/wiki/Helmholtz%E2%80%93Kohlrausch%20effect | The Helmholtz–Kohlrausch effect (after Hermann von Helmholtz and V. A. Kohlrausch) is a perceptual phenomenon wherein the intense saturation of spectral hue is perceived as part of the color's luminance. This brightness increase by saturation, which grows stronger as saturation increases, might better be called chromatic luminance, since "white" or achromatic luminance is the standard of comparison. It appears in both self-luminous and surface colors, although it is most pronounced in spectral lights.
Lightness
Even when they have the same luminance, colored lights seem brighter to human observers than white light does. The way humans perceive the brightness of the lights is different for everyone. When the colors are more saturated, our eyes interpret it as the color's luminance and chroma. This makes us believe that the colors are actually brighter. An exception to this is when the human observer is red-green colorblind, they cannot distinguish the differences between the lightness of the colors. Certain colors do not have significant effect, however; any hue of colored lights still seem brighter than white light that has the same luminance. Two colors that do not have as great of an Helmholtz–Kohlrausch effect as the others are green and yellow.
The Helmholtz–Kohlrausch effect is affected by the viewing environment. This includes the surroundings of the object and the lighting that the object is being viewed under. The Helmholtz–Kohlrausch effect works best in darker environments where there are not any other outside factors influencing the colors. For example, this is why theaters are all dark environments.
An example of this lightness factor would be if there were different colors on a grey background that all are of the same lightness. Obviously the colors look different because they are different colors not just grey, but if the image were converted all to grey scale, all of the colors would match the grey background because they all have the same lightnes |
https://en.wikipedia.org/wiki/IEEE%20802.8 | The Fiber Optic Technical Advisory Group was to create a LAN standard for fiber optic media used in token passing computer networks like FDDI. This was part of the IEEE 802 group of standards.
The group had given up and disbanded itself and is no longer a part of IEEE standards. |
https://en.wikipedia.org/wiki/List%20of%20countries%20by%20average%20yearly%20temperature | Average yearly temperature is calculated by averaging the minimum and maximum daily temperatures in the country, averaged for the years 1961–1990, based on gridded climatologies from the Climatic Research Unit elaborated in 2011.
Data source: Mitchell, T.D., Carter, T.R., Jones, P.D., Hulme, M., New, M., 2003: A Comprehensive Set of High-Resolution Grids of Monthly Climate for Europe and the Globe: the Observed Record (1901-2000) and 16 Scenarios (2001-2100). J. Climate: submitted.
See also
List of countries by average annual precipitation
Notes |
https://en.wikipedia.org/wiki/Theoretical%20strength%20of%20a%20solid | The theoretical strength of a solid is the maximum possible stress a perfect solid can withstand. It is often much higher than what current real materials can achieve. The lowered fracture stress is due to defects, such as interior or surface cracks. One of the goals for the study of mechanical properties of materials is to design and fabricate materials exhibiting strength close to the theoretical limit.
Definition
When a solid is in tension, its atomic bonds stretch, elastically. Once a critical strain is reached, all the atomic bonds on the fracture plane rupture and the material fails mechanically. The stress at which the solid fractures is the theoretical strength, often denoted as . After fracture, the stretched atomic bonds return to their initial state, except that two surfaces have formed.
The theoretical strength is often approximated as:
where
is the maximum theoretical stress the solid can withstand.
E is the Young's Modulus of the solid.
Derivation
The stress-displacement, or vs x, relationship during fracture can be approximated by a sine curve, , up to /4. The initial slope of the vs x curve can be related to Young's modulus through the following relationship:
where
is the stress applied.
E is the Young's Modulus of the solid.
is the strain experienced by the solid.
x is the displacement.
The strain can be related to the displacement x by , and is the equilibrium inter-atomic spacing. The strain derivative is therefore given by
The relationship of initial slope of the vs x curve with Young's modulus thus becomes
The sinusoidal relationship of stress and displacement gives a derivative:
By setting the two together, the theoretical strength becomes:
The theoretical strength can also be approximated using the fracture work per unit area, which result in slightly different numbers. However, the above derivation and final approximation is a commonly used metric for evaluating the advantages of a material's mechanical properti |
https://en.wikipedia.org/wiki/Field%20strength%20meter | In telecommunications, a field strength meter is an instrument that measures the electric field strength emanating from a transmitter.
The relation between the electric field and the transmitted power
In ideal free space, the electric field strength produced by a transmitter with an isotropic radiator is readily calculated.
where
is the electric field strength in volts per meter
is the transmitter power output in watts
is the distance from the radiator in meters
The factor is an approximation of
where is the impedance of free space. is the symbol for ohms.
It is clear that electric field strength is inversely proportional to the distance between the transmitter and the receiver. However, this relation is impractical for calculating the field strength produced by terrestrial transmitters, where reflections and attenuation caused by objects around the transmitter or receiver may affect the electrical field strength considerably.
Field strength meter
Field strength meter is actually a simple receiver. The RF signal is detected and fed to a microammeter, which is scaled in dBμ. The frequency range of the tuner is usually within the terrestrial broadcasting bands. Some FS meters can also receive satellite (TVRO and RRO) frequencies. Most modern FS meters have AF and VF circuits and can be used as standard receivers. Some FS meters are also equipped with printers to record received field strength.
Antennas
When measuring with a field strength meter it is important to use a calibrated antenna such as the standard antenna supplied with the meter. For precision measurements the antenna must be at a standard height. A value of standard height frequently employed for VHF and UHF measurements is . Gain correction tables may be provided with the meter, that take into account the change of antenna gain with frequency.
Minimum field strength criteria
The CCIR defines the minimum field strength for satisfactory reception. These are shown in the table below. |
https://en.wikipedia.org/wiki/TF1 | TF1 (; standing for Télévision Française 1) is a French commercial television network owned by TF1 Group, controlled by the Bouygues conglomerate. TF1's average market share of 24% makes it the most popular domestic network.
TF1 is part of the TF1 Group of mass media companies, which also includes the news channel LCI. It previously owned the satellite TV provider TPS, which was sold to Canal+ Group.
The network is a supporter of the Hybrid Broadcast Broadband TV (HBBTV) initiative promoting and establishing an open European standard for hybrid set-top boxes for the reception of terrestrial TV and broadband multimedia applications with a single user interface.
History
It was the only television channel in France for 28 years, and has changed its name numerous times since the creation of Radio-PTT Vision on 26 April 1935, making it among the oldest television stations in the world, and one of the very few prewar television stations to remain in existence to the present day. It became Radiodiffusion nationale Télévision (RN Télévision) in 1937, Fernsehsender Paris (Paris Television) during German occupation in 1943, RDF Télévision française in 1944, RTF Télévision in 1949, la Première chaîne de la RTF in 1963 following the creation of the second channel, la Première chaîne de l'ORTF in 1964 and finally, Télévision Française 1 (TF1) in 1975.
Radio-PTT Vision (1935–1937)
The first public demonstration of a 30-line mechanical television took place on April 14, 1931. The image rendering was an improvement upon Baird's thanks to the development of the "moving light point" system and the use of a camera with Weiller mirror drums by the engineer René Barthélemy, head of the radio laboratory of the Compagnie desmètres (CdC) of Montrouge. In charge of French broadcasting, the PTT administration carried out some rudimentary television experiments from December 1931 by broadcasting experimental 30 to 45 minute broadcasts at variable times from Monday to Saturday with Baird |
https://en.wikipedia.org/wiki/Fitts%27s%20law | Fitts's law (often cited as Fitts' law) is a predictive model of human movement primarily used in human–computer interaction and ergonomics. The law predicts that the time required to rapidly move to a target area is a function of the ratio between the distance to the target and the width of the target. Fitts's law is used to model the act of pointing, either by physically touching an object with a hand or finger, or virtually, by pointing to an object on a computer monitor using a pointing device. It was initially developed by Paul Fitts.
Fitts's law has been shown to apply under a variety of conditions; with many different limbs (hands, feet, the lower lip, head-mounted sights), manipulanda (input devices), physical environments (including underwater), and user populations (young, old, special educational needs, and drugged participants).
Original model formulation
The original 1954 paper by Paul Morris Fitts proposed a metric to quantify the difficulty of a target selection task.
The metric was based on an information analogy, where the distance to the center of the target (D) is like a signal and the tolerance or width of the target (W) is like noise.
The metric is Fitts's index of difficulty (ID, in bits):
Fitts also proposed an index of performance (IP, in bits per second) as a measure of human performance. The metric combines a task's index of difficulty (ID) with the movement time (MT, in seconds) in selecting the target. In Fitts's words,
"The average rate of information generated by a series of movements is the average information per movement divided by the time per movement." Thus,
Today, IP is more commonly called throughput (TP). It is also common to include an adjustment for accuracy in the calculation.
Researchers after Fitts began the practice of building linear regression equations and examining the correlation (r) for goodness of fit. The equation expresses the relationship between
MT and the D and W task parameters:
where:
MT is the avera |
https://en.wikipedia.org/wiki/Rademacher%20complexity | In computational learning theory (machine learning and theory of computation), Rademacher complexity, named after Hans Rademacher, measures richness of a class of real-valued functions with respect to a probability distribution.
Definitions
Rademacher complexity of a set
Given a set , the Rademacher complexity of A is defined as follows:
where are independent random variables drawn from the Rademacher distribution i.e. for , and . Some authors take the absolute value of the sum before taking the supremum, but if is symmetric this makes no difference.
Rademacher complexity of a function class
Let be a sample of points and consider a function class of real-valued functions over . Then, the empirical Rademacher complexity of given is defined as:
This can also be written using the previous definition:
where denotes function composition, i.e.:
Let be a probability distribution over .
The Rademacher complexity of the function class with respect to for sample size is:
where the above expectation is taken over an identically independently distributed (i.i.d.) sample generated according to .
Intuition
The Rademacher complexity is typically applied on a function class of models that are used for classification, with the goal of measuring their ability to classify points drawn from a probability space under arbitrary labellings. When the function class is rich enough, it contains functions that can appropriately adapt for each arrangement of labels, simulated by the random draw of under the expectation, so that this quantity in the sum is maximised.
Examples
1. contains a single vector, e.g., . Then:
The same is true for every singleton hypothesis class.
2. contains two vectors, e.g., . Then:
Using the Rademacher complexity
The Rademacher complexity can be used to derive data-dependent upper-bounds on the learnability of function classes. Intuitively, a function-class with smaller Rademacher complexity is easier to learn.
Bounding the repre |
https://en.wikipedia.org/wiki/Vaccinia | Vaccinia virus (VACV or VV) is a large, complex, enveloped virus belonging to the poxvirus family. It has a linear, double-stranded DNA genome approximately 190 kbp in length, which encodes approximately 250 genes. The dimensions of the virion are roughly 360 × 270 × 250 nm, with a mass of approximately 5–10 fg. The vaccinia virus is the source of the modern smallpox vaccine, which the World Health Organization (WHO) used to eradicate smallpox in a global vaccination campaign in 1958–1977. Although smallpox no longer exists in the wild, vaccinia virus is still studied widely by scientists as a tool for gene therapy and genetic engineering.
Smallpox had been an endemic human disease that had a 30% fatality rate. In 1796, the British doctor Edward Jenner proved that an infection with the relatively mild cowpox virus would also confer immunity to the deadly smallpox. Jenner referred to cowpox as variolae vaccinae (smallpox of the cow). However, the origins of the smallpox vaccine became murky over time, especially after Louis Pasteur developed laboratory techniques for creating vaccines in the 19th century. Allan Watt Downie demonstrated in 1939 that the modern smallpox vaccine was serologically distinct from cowpox, and vaccinia was subsequently recognized as a separate viral species. Whole-genome sequencing has revealed that vaccinia is most closely related to horsepox, and the cowpox strains found in Great Britain are the least closely related to vaccinia.
Classification of vaccinia infections
In addition to the morbidity of uncomplicated primary vaccination, transfer of infection to other sites by scratching, and post-vaccinial encephalitis, other complications of vaccinia infections may be divided into the following types:
Generalized vaccinia
Eczema vaccinatum
Progressive vaccinia (vaccinia gangrenosum, vaccinia necrosum)
Roseola vaccinia
Origin
Vaccinia virus is closely related to the virus that causes cowpox; historically the two were often considered |
https://en.wikipedia.org/wiki/Goldbach%27s%20conjecture | Goldbach's conjecture is one of the oldest and best-known unsolved problems in number theory and all of mathematics. It states that every even natural number greater than 2 is the sum of two prime numbers.
The conjecture has been shown to hold for all integers less than , but remains unproven despite considerable effort.
History
On 7 June 1742, the Prussian mathematician Christian Goldbach wrote a letter to Leonhard Euler (letter XLIII), in which he proposed the following conjecture:
Goldbach was following the now-abandoned convention of considering 1 to be a prime number, so that a sum of units would be a sum of primes.
He then proposed a second conjecture in the margin of his letter, which implies the first:
Euler replied in a letter dated 30 June 1742 and reminded Goldbach of an earlier conversation they had had (), in which Goldbach had remarked that the first of those two conjectures would follow from the statement
This is in fact equivalent to his second, marginal conjecture.
In the letter dated 30 June 1742, Euler stated:
Each of the three conjectures above has a natural analog in terms of the modern definition of a prime, under which 1 is excluded.
A modern version of the first conjecture is:
A modern version of the marginal conjecture is:
And a modern version of Goldbach's older conjecture of which Euler reminded him is:
These modern versions might not be entirely equivalent to the corresponding original statements. For example, if there were an even integer larger than 4, for a prime, that could not be expressed as the sum of two primes in the modern sense, then it would be a counterexample to the modern version of the third conjecture (without being a counterexample to the original version). The modern version is thus probably stronger (but in order to confirm that, one would have to prove that the first version, freely applied to any positive even integer , could not possibly rule out the existence of such a specific counterexample ). In any |
https://en.wikipedia.org/wiki/Pectin | Pectin ( : "congealed" and "curdled") is a heteropolysaccharide, a structural acid contained in the primary lamella, in the middle lamella, and in the cell walls of terrestrial plants. The principal, chemical component of pectin is galacturonic acid (a sugar acid derived from galactose) which was isolated and described by Henri Braconnot in 1825. Commercially produced pectin is a white-to-light-brown powder, produced from citrus fruits for use as an edible gelling agent, especially in jams and jellies, dessert fillings, medications, and sweets; and as a food stabiliser in fruit juices and milk drinks, and as a source of dietary fiber.
Biology
Pectin is composed of complex polysaccharides that are present in the primary cell walls of a plant, and are abundant in the green parts of terrestrial plants.
Pectin is the principal component of the middle lamella, where it binds cells. Pectin is deposited by exocytosis into the cell wall via vesicles produced in the Golgi apparatus. The amount, structure and chemical composition of pectin is different among plants, within a plant over time, and in various parts of a plant. Pectin is an important cell wall polysaccharide that allows primary cell wall extension and plant growth. During fruit ripening, pectin is broken down by the enzymes pectinase and pectinesterase, in which process the fruit becomes softer as the middle lamellae break down and cells become separated from each other. A similar process of cell separation caused by the breakdown of pectin occurs in the abscission zone of the petioles of deciduous plants at leaf fall.
Pectin is a natural part of the human diet, but does not contribute significantly to nutrition. The daily intake of pectin from fruits and vegetables can be estimated to be around 5 g if approximately 500 g of fruits and vegetables are consumed per day.
In human digestion, pectin binds to cholesterol in the gastrointestinal tract and slows glucose absorption by trapping carbohydrates. Pectin is |
https://en.wikipedia.org/wiki/DOS%20Navigator | DOS Navigator (DN) is an orthodox file manager for DOS, OS/2, and Windows.
Influence
DOS Navigator is an influential early implementation of orthodox file manager (OFM). By implementing three additional types of virtual file systems (VFS): XTree, Briefcase and list-based, DN launched a new generation of OFMs. It offers unlimited panels and many new important features, making it one of the most powerful (and complex) OFMs.
History
The initial version of DN I (v 0.90) was released in 1991, and written by Stefan Tanurkov, Andrew Zabolotny and Sergey Melnik (all from Chișinău, Moldova). After that, DN was rewritten using Turbo Vision by Stefan Tanurkov and Dmitry Dotsenko (Dotsenko developed DN at Moscow State University). These versions are sometimes referred as DN II.
In 1993, Slava Filimonov invited Stefan to join him to continue producing and publishing DN with joint efforts. Slava programmed new components, design and made countless optimizations and improvements. He wrote a new software key protection system that remained unbroken for almost four years after its introduction.
DN II was actively developed until the start of 1995, until version 1.35. Several other programmers participated in development after version 1.35. Starting from version 1.37, Filimonov and Ilya Bagdasarov were in charge of bug-fixing. Filimonov and Bagdasarov solely maintained, developed and released versions 1.37 through 1.39. After they left, DN was maintained again by Tanurkov and Maxim Masiutin.
In 1998, the development mostly took a bug-fixing direction as Ritlabs' product The Bat! became a more promising software product with much better commercial potential. The last shareware version was 1.50. In late 1999, Ritlabs decided to make version 1.51 of the DOS Navigator completely free with freely available source code.
Several open source DN branches currently exist including win32/dpmi/os2 version "dn/2" and Linux port attempt "dn2l".
Disadvantages
The original DN contains a la |
https://en.wikipedia.org/wiki/%C3%82u%20C%C6%A1 | Âu Cơ (chữ Hán: 甌姬; ) was, according to the creation myth of the Vietnamese people, an immortal mountain snow goddess who married Lạc Long Quân (), and bore an egg sac that hatched a hundred children known collectively as Bách Việt, ancestors to the Vietnamese people. Âu Cơ is often honored as the mother of Vietnamese civilization.
Mythology
Âu Cơ was a beautiful young tiên who lived high in the snow-capped mountains. She traveled to help those who suffered from illnesses since she was very skillful in medicine and had a sympathetic heart. One day, a monster suddenly appeared before her while she was on her travels. It frightened her, so she transformed into a crane to fly away. Lạc Long Quân, the dragon king from the sea, passed by and saw the crane in danger. He grabbed a nearby rock and killed the monster with it. When Âu Cơ stopped flying to see the very person that saved her, she turned back into a tiên and instantly fell in love with her savior. She soon bore an egg sac, from which hatched a hundred children. However, despite their love for each other, Âu Cơ had always desired to be in the mountains again and Lạc Long Quân, too, yearned for the sea where the length of days are measured by seasons. They separated, each taking 50 children. Âu Cơ settled in the Vietnamese snow-covered mountains where she raised fifty young, intelligent, strong leaders, later known as the Hùng Vương, Hùng kings.
In Vietnamese literature
The books Đại Việt sử ký toàn thư (from the 15th century) and Lĩnh Nam chích quái (Wonders plucked from the dust of Linh-nam, from the 14th century) mention the legend. In Đại Việt sử ký toàn thư Âu Cơ is the daughter of Đế Lai (also known as Đế Ai 帝哀, or Emperor Ai, who was a descendant of Shennong), while in Lĩnh Nam chích quái, Âu Cơ was Đế Lai's concubine before she married off to Lạc Long Quân. Additionally in Lĩnh Nam chích quái, Âu Cơ gave birth to an egg sac but threw it away in the field, believing the egg sac to carry bad omens. Ngô Sĩ |
https://en.wikipedia.org/wiki/Surface%20plasmon%20resonance%20microscopy | Surface plasmon resonance microscopy (SPRM), also called surface plasmon resonance imaging (SPRI), is a label free analytical tool that combines the surface plasmon resonance of metallic surfaces with imaging of the metallic surface.
The heterogeneity of the refractive index of the metallic surface imparts high contrast images, caused by the shift in the resonance angle. SPRM can achieve a sub-nanometer thickness sensitivity and lateral resolution achieves values of micrometer scale. SPRM is used to characterize surfaces such as self-assembled monolayers, multilayer films, metal nanoparticles, oligonucleotide arrays, and binding and reduction reactions. Surface plasmon polaritons are surface electromagnetic waves coupled to oscillating free electrons of a metallic surface that propagate along a metal/dielectric interface. Since polaritons are highly sensitive to small changes in the refractive index of the metallic material, it can be used as a biosensing tool that does not require labeling. SPRM measurements can be made in real-time, such as measuring binding kinetics of membrane proteins in single cells, or DNA hybridization.
History
The concept of classical SPR has been since 1968 but the SPR imaging technique was introduced in 1988 by Rothenhäusler and Knoll. Capturing a high resolution image of low contrast samples for optical measuring techniques is a near impossible task until the introduction of SPRM technique that came into existence in the year 1988. In SPRM technique, plasmon surface polariton (PSP) waves are used for illumination. In simple words, SPRI technology is an advanced version of classical SPR analysis, where the sample is monitored without label through the use of a CCD camera. The SPRI technology with the aid of CCD camera gives advantage of recording the sensograms and SPR images, and simultaneously analyzes hundreds of interactions.
Principles
Surface plasmons or surface plasmon polaritons are generated by coupling of electrical field wit |
https://en.wikipedia.org/wiki/Credential%20lag | Credential lag usually occurs for a user who is attempting to log in to a system that relies on updating its cached or otherwise saved user credentials by conferring with Active Directory or similar database.
When a user changes or resets their password, it may take some time for the third party software to retrieve the new credentials from the active directory catalog; for instance, an intranet service that queries AD for permissions.
Example
User "ANOther" is prompted to change her password as it has expired on her windows domain account. Once changed, Active Directory is updated, and the user proceeds to log in.
However, it may be the case that the internal intranet site only refreshes every 15 minutes, therefore, until the intranet refreshes its credential database, the user is unable to log into the intranet service for up to 15 minutes. |
https://en.wikipedia.org/wiki/Centroacinar%20cell | Centroacinar cells are spindle-shaped cells in the exocrine pancreas. They represent an extension of the intercalated duct into each pancreatic acinus. These cells are commonly known as duct cells, and secrete an aqueous bicarbonate solution under stimulation by the hormone secretin. They also secrete mucin.
The intercalated ducts take the bicarbonate to intralobular ducts which become lobular ducts. These lobular ducts finally converge to form the main pancreatic duct.
See also
List of human cell types derived from the germ layers
List of distinct cell types in the adult human body |
https://en.wikipedia.org/wiki/Tasman%20Front | The Tasman Front is a relatively warm water east-flowing surface current and thermal boundary that separates the Coral Sea to the north and the Tasman Sea to the south.
Naming
The name was proposed by Denham and Crook in 1976, to describe a thermal front that extends from Australia and New Zealand between the Coral Sea and Tasman Sea.
Geography
Originating in the edge of the East Australian Current (EAC), the Tasman Front meanders eastward between longitudes 152° E and 164° E and latitudes 31° S and 37° S, then reattaches to the coastline at New Zealand, forming the East Auckland Current.
Topography plays a dominant role in establishing the Tasman Front. Data on the Tasman Front shows that the path of the front is influenced in part by the forcing of the flow over the major ridge systems. Meanders observed in the Tasman Front can be driven by meridional flows along ridges such as those observed at the New Caledonia Trough (166° E) and the Norfolk Ridge (167° E). Abyssal currents also drive meanders associated with the Lord Howe Rise (161° E) and Dampier Ridge (159° E).
Oceanography
There have been a number of observational and modeling studies on this front in addition to a number of paleo-oceanographic studies of marine sediments. Contrarily, there have been few biological observational studies, but those have been conducted resulted in relating the physical features of the front to properties of fish communities. Likewise, there are even fewer studies relating biogeochemical properties to physical processes of the Tasman Front.
See also
Lord Howe Marine Park |
https://en.wikipedia.org/wiki/Artificial%20skin | Artificial skin is a collagen scaffold that induces regeneration of skin in mammals such as humans. The term was used in the late 1970s and early 1980s to describe a new treatment for massive burns. It was later discovered that treatment of deep skin wounds in adult animals and humans with this scaffold induces regeneration of the dermis. It has been developed commercially under the name Integra and is used in massively burned patients, during plastic surgery of the skin, and in treatment of chronic skin wounds.
Alternatively, the term "artificial skin" sometimes is used to refer to skin-like tissue grown in a laboratory, although this technology is still quite a way away from being viable for use in the medical field. 'Artificial skin' can also refer to flexible semiconductor materials that can sense touch for those with prosthetic limbs (also experimental).
Background
The skin is the largest organ in the human body. Skin is made up of three layers, the epidermis, dermis and the fat layer, also called the hypodermis. The epidermis is the outer layer of skin that keeps vital fluids in and harmful bacteria out of the body. The dermis is the inner layer of skin that contains blood vessels, nerves, hair follicles, oil, and sweat glands. Severe damage to large areas of skin exposes the human organism to dehydration and infections that can result in death.
Traditional ways of dealing with large losses of skin have been to use skin grafts from the patient (autografts) or from an unrelated donor or a cadaver. The former approach has the disadvantage that there may not be enough skin available, while the latter suffers from the possibility of rejection or infection. Until the late twentieth century, skin grafts were constructed from the patient's own skin. This became a problem when skin had been damaged extensively, making it impossible to treat severely injured patients with autografts only.
Regenerated skin: discovery and clinical use
A process for inducing regen |
https://en.wikipedia.org/wiki/Renata%20Mansini | Renata Mansini (born 22 August 1968) is an Italian applied mathematician, economist, and operations researcher known for her research on problems in mathematical optimization including portfolio optimization and vehicle routing. She is a professor of operations research at the University of Brescia.
Education
Mansini earned a laurea in economics and business from the University of Brescia in 1991–1992, winning a prize from the Associazione Italiana di Studio del Lavoro for the best thesis in applied mathematics. She completed a doctorate in 1996–1997 at the University of Bergamo, with the dissertation Modelli di programmazione lineare mista intera per problemi finanziari: analisi, algoritmi e risultati computazionali [mixed integer linear programming models for financial problems: analysis, algorithms, and computational results].
Book
Mansini is the co-author, with Włodzimierz Ogryczak and M. Grazia Speranza, of the book Linear and Mixed Integer Programming for Portfolio Optimization (EURO Advanced Tutorials on Operational Research, Springer, 2015). |
https://en.wikipedia.org/wiki/Minus%20Cube | The Minus Cube (aka BLOXBOX by Piet Hein; aka Varikon Box) is a 3D mechanical variant of the n-puzzle, which was manufactured in the Soviet Union. It consists of a bonded transparent plastic box containing seven small cubes, each glued together from two U-shape parts: one white and one coloured. The length of one side of the interior of the box is slightly more than twice the length of the side of a small cube. There is an empty space for one small cube inside the box, and the small cubes are moveable inside the box by tilting the box, causing a cube to fall into the space. The goal of the puzzle is to shuffle the cubes in such a way that on each side of the box, all of the faces of the small cubes have the same color.
There were two types of Minus Cubes manufactured: the so-called "Moscow Minus Cube" (red–white) and "Sverdlovsk Minus Cube" (blue–white), each named after the cities in which they were produced. They differed only in the orientation of one of the small cubes. Because of this difference, there are 12 times as many "solved" arrangements for the Moscow Minus Cube, and thus the Sverdlovsk Minus Cube is 12 times as difficult to solve. However, if one does not confine oneself to these two types of the Minus Cube, there are 48 Minus Cube variants that can be solved.
See also
15 puzzle
Combination puzzle
Mechanical puzzle |
https://en.wikipedia.org/wiki/SAP%20BI%20Accelerator | In computing, the SAP BW Accelerator is a computer appliance - preinstalled software on predefined hardware - which is used to speed up OLAP queries. The software was initially known as the BI Accelerator.
SAP BW Accelerator includes indexes that are vertically inverted reproductions of all the data included in InfoCubes (i.e., fact and dimension tables as well as master data). Note that there is no relational or other database management systems in BW Accelerator. There is only a file system, and indexes are essentially held as flat files. The second primary component of SAP BW Accelerator is the engine that processes the queries in memory - it uses the SAP TREX search engine. The software is running on an expandable rack of blade servers. The operating system used for BW Accelerator is 64-bit SUSE Linux Enterprise Server (SLES).
Hardware partners
The software is optimized for specific hardware and operating system combinations.
The list of partners which deliver the appliance is:
IBM BW Accelerator solution
HP
Fujitsu Siemens Computers
Sun BI Accelerator Offering |
https://en.wikipedia.org/wiki/Macbeath%20surface | In Riemann surface theory and hyperbolic geometry, the Macbeath surface, also called Macbeath's curve or the Fricke–Macbeath curve, is the genus-7 Hurwitz surface.
The automorphism group of the Macbeath surface is the simple group PSL(2,8), consisting of 504 symmetries.
Triangle group construction
The surface's Fuchsian group can be constructed as the principal congruence subgroup of the (2,3,7) triangle group in a suitable tower of principal congruence subgroups. Here the choices of quaternion algebra and Hurwitz quaternion order are described at the triangle group page. Choosing the ideal in the ring of integers, the corresponding principal congruence subgroup defines this surface of genus 7. Its systole is about 5.796, and the number of systolic loops is 126 according to R. Vogeler's calculations.
It is possible to realize the resulting triangulated surface as a non-convex polyhedron without self-intersections.
Historical note
This surface was originally discovered by , but named after Alexander Murray Macbeath due to his later independent rediscovery of the same curve. Elkies writes that the equivalence between the curves studied by Fricke and Macbeath "may first have been observed by Serre in a 24.vii.1990 letter to Abhyankar".
See also
Klein quartic
First Hurwitz triplet
Notes |
https://en.wikipedia.org/wiki/WPGF-LD | WPGF-LD (channel 6) is a low-power television station in Memphis, Tennessee, United States. The station's audio channel, transmitting at 87.75 MHz (or VHF channel 6), lies within the FM band; as a result, WPGF-LD's audio channel operates as a radio station at 87.7 FM. Owned by Flinn Broadcasting, the station airs an urban oldies format via the 87.75 MHz audio channel under the brand "Right On Radio". WPGF-LD's transmitter is located on the northeast side of Memphis near Bartlett, Tennessee, just off US 64.
Flinn Broadcasting surrendered WPGF-LD's license to the Federal Communications Commission on June 20, 2021, and the FCC canceled it the following day. At the time, it was an affiliate of Estrella TV. The station returned to the air in January 2022 under a new license and converted to ATSC 3.0 broadcasting that month. On July 20, 2023, an FCC "Report and Order" included this station as one of 13 "FM6" stations allowed to continue to operate an FM radio broadcast, as a "ancillary or supplementary" service. |
https://en.wikipedia.org/wiki/235%20%28number%29 | 235 (two hundred [and] thirty-five) is the integer following 234 and preceding 236.
Additionally, 235 is:
a semiprime.
a heptagonal number.
a centered triangular number.
therefore a figurate number in two ways.
palindromic in bases 4 (32234), 7 (4547), 8 (3538), 13 (15113), and 46 (5546).
a Harshad number in bases 6, 47, 48, 95, 116, 189 and 231.
a Smarandache–Wellin number
Also:
There are 235 different trees with 11 unlabeled nodes.
If an equilateral triangle is subdivided into smaller equilateral triangles whose side length is 1/9 as small, the resulting "matchstick arrangement" will have exactly 235 different equilateral triangles of varying sizes in it. |
https://en.wikipedia.org/wiki/Heino%20Meyer-Bahlburg | Heino F. L. Meyer-Bahlburg (born 1940) is a German-born psychologist best known for his work on biology of sexual orientation, gender identity, intersexuality, and HIV.
Education and career
Meyer-Bahlburg earned his Diplom from University of Hamburg in 1966 and his Dr. rer. nat. in Psychology from University of Düsseldorf in 1970. He took a position at State University of New York, Buffalo and at Children’s Hospital in Buffalo, New York in 1970. Since 1977 he has held appointments at New York State Psychiatric Institute and Columbia University where he has been Professor of Clinical Psychology since 1990. In 1978, he took a position at New York Presbyterian Hospital and has been a Full Professional Psychologist there since 1990. Since 1987, he has been affiliated with the HIV Center for Clinical and Behavioral Studies.
Meyer-Bahlburg believes homosexuality may be an issue of brain chemistry. He has observed that women who took the synthetic estrogen Diethylstilbestrol when pregnant were more likely to have daughters with bisexual or homosexual tendencies. His research interests include the effect of biological factors, medical treatments, gender assignment, and rearing conditions in the development of gender-related behavior, temperament, sexual orientation, and gender identity in various forms of intersexuality. He has published on the effect of genital ambiguity and genital surgery on later sexual functioning in 46,XX congenital adrenal hyperplasia. Meyer-Bahlburg published with John Money and others on the topic of psychoneuroendocrinology and its effects on sexual orientation and gender identity. In collaboration with Maria New, Meyer-Bahlburg published a long term analysis of the psychological effects of the use of prenatal dexamethasone to treat Congenital Adrenal Hyperplasia.
Meyer-Bahlburg served on the American Psychiatric Association DSM-III Gender Identity Disorder Committee, and the DSM-IV Subcommittee on Gender Identity Disorders. He was also Advise |
https://en.wikipedia.org/wiki/Clp%20protease%20family | In molecular biology, the CLP protease family is a family of serine peptidases belong to the MEROPS peptidase family S14 (ClpP endopeptidase family, clan SK). ClpP is an ATP-dependent protease that cleaves a number of proteins, such as casein and albumin. It exists as a heterodimer of ATP-binding regulatory A and catalytic P subunits, both of which are required for effective levels of protease activity in the presence of ATP, although the P subunit alone does possess some catalytic activity.
Proteases highly similar to ClpP have been found to be encoded in the genome of bacteria, in the mitochondria of metazoa, some viruses and in the chloroplast of plants. A number of the proteins in this family are classified as non-peptidase homologues as they have been found experimentally to be without peptidase activity, or lack amino acid residues that are believed to be essential for catalytic activity.
Mutations in mitochondrial CLPP are associated with Perrault syndrome and cause a variety of molecular defects, from the loss of ATPase docking, to the activation or inhibition of peptidase activity.
See also
Endopeptidase Clp
ATP-dependent Clp protease proteolytic subunit |
https://en.wikipedia.org/wiki/Henry%20Dudeney | Henry Ernest Dudeney (10 April 1857 – 23 April 1930) was an English author and mathematician who specialised in logic puzzles and mathematical games. He is known as one of the country's foremost creators of mathematical puzzles.
Early life
Dudeney was born in the village of Mayfield, East Sussex, England, one of six children of Gilbert and Lucy Dudeney. His grandfather, John Dudeney, was well known as a self-taught mathematician and shepherd; his initiative was much admired by his grandson. Dudeney learned to play chess at an early age, and continued to play frequently throughout his life. This led to a marked interest in mathematics and the composition of puzzles. Chess problems in particular fascinated him during his early years.
Career
Although Dudeney spent his career in the Civil Service, he continued to devise various problems and puzzles. Dudeney's first puzzle contributions were submissions to newspapers and magazines, often under the pseudonym of "Sphinx." Much of this earlier work was a collaboration with American puzzlist Sam Loyd; in 1890, they published a series of articles in the English penny weekly Tit-Bits.
Dudeney later contributed puzzles under his real name to publications such as The Weekly Dispatch, The Queen, Blighty, and Cassell's Magazine. For twenty years, he had a successful column, "Perplexities", in The Strand Magazine, edited by the former editor of Tit-Bits, George Newnes. Dudeney continued to exchange puzzles with fellow recreational mathematician Sam Loyd for a while, but broke off the correspondence and accused Loyd of stealing his puzzles and publishing them under his own name.
Some of Dudeney's most famous innovations were his 1903 success at solving the Haberdasher's Puzzle (Cut an equilateral triangle into four pieces that can be rearranged to make a square) and publishing the first known crossnumber puzzle, in 1926. He has also been credited with discovering new applications of digital roots. Dudeney was a leading exponent |
https://en.wikipedia.org/wiki/Biaugmented%20triangular%20prism | In geometry, the biaugmented triangular prism is one of the Johnson solids (). As the name suggests, it can be constructed by augmenting a triangular prism by attaching square pyramids () to two of its equatorial faces.
It is related to the augmented triangular prism () and the triaugmented triangular prism ().
External links
Johnson solids |
https://en.wikipedia.org/wiki/Exceptional%20inverse%20image%20functor | In mathematics, more specifically sheaf theory, a branch of topology and algebraic geometry, the exceptional inverse image functor is the fourth and most sophisticated in a series of image functors for sheaves. It is needed to express Verdier duality in its most general form.
Definition
Let f: X → Y be a continuous map of topological spaces or a morphism of schemes. Then the exceptional inverse image is a functor
Rf!: D(Y) → D(X)
where D(–) denotes the derived category of sheaves of abelian groups or modules over a fixed ring.
It is defined to be the right adjoint of the total derived functor Rf! of the direct image with compact support. Its existence follows from certain properties of Rf! and general theorems about existence of adjoint functors, as does the unicity.
The notation Rf! is an abuse of notation insofar as there is in general no functor f! whose derived functor would be Rf!.
Examples and properties
If f: X → Y is an immersion of a locally closed subspace, then it is possible to define
f!(F) := f∗ G,
where G is the subsheaf of F of which the sections on some open subset U of Y are the sections s ∈ F(U) whose support is contained in X. The functor f! is left exact, and the above Rf!, whose existence is guaranteed by abstract nonsense, is indeed the derived functor of this f!. Moreover f! is right adjoint to f!, too.
Slightly more generally, a similar statement holds for any quasi-finite morphism such as an étale morphism.
If f is an open immersion, the exceptional inverse image equals the usual inverse image.
Duality of the exceptional inverse image functor
Let be a smooth manifold of dimension and let be the unique map which maps everything to one point. For a ring , one finds that is the shifted -orientation sheaf.
On the other hand, let be a smooth -variety of dimension . If denotes the structure morphism then is the shifted canonical sheaf on .
Moreover, let be a smooth -variety of dimension and a prime invertible in . Then wher |
https://en.wikipedia.org/wiki/Fr%C3%A9chet%20surface | In mathematics, a Fréchet surface is an equivalence class of parametrized surfaces in a metric space. In other words, a Fréchet surface is a way of thinking about surfaces independently of how they are "written down" (parametrized). The concept is named after the French mathematician Maurice Fréchet.
Definitions
Let be a compact 2-dimensional manifold, either closed or with boundary, and let be a metric space. A parametrized surface in is a map
that is continuous with respect to the topology on and the metric topology on Let
where the infimum is taken over all homeomorphisms of to itself. Call two parametrized surfaces and in equivalent if and only if
An equivalence class of parametrized surfaces under this notion of equivalence is called a Fréchet surface; each of the parametrized surfaces in this equivalence class is called a parametrization of the Fréchet surface
Properties
Many properties of parametrized surfaces are actually properties of the Fréchet surface, that is, of the whole equivalence class, and not of any particular parametrization.
For example, given two Fréchet surfaces, the value of is independent of the choice of the parametrizations and and is called the Fréchet distance between the Fréchet surfaces. |
https://en.wikipedia.org/wiki/Software%20design%20pattern | In software engineering, a software design pattern is a general, reusable solution to a commonly occurring problem within a given context in software design. It is not a finished design that can be transformed directly into source or machine code. Rather, it is a description or template for how to solve a problem that can be used in many different situations. Design patterns are formalized best practices that the programmer can use to solve common problems when designing an application or system.
Object-oriented design patterns typically show relationships and interactions between classes or objects, without specifying the final application classes or objects that are involved. Patterns that imply mutable state may be unsuited for functional programming languages. Some patterns can be rendered unnecessary in languages that have built-in support for solving the problem they are trying to solve, and object-oriented patterns are not necessarily suitable for non-object-oriented languages.
Design patterns may be viewed as a structured approach to computer programming intermediate between the levels of a programming paradigm and a concrete algorithm.
History
Patterns originated as an architectural concept by Christopher Alexander as early as 1977 (c.f. "The Pattern of Streets," JOURNAL OF THE AIP, September, 1966, Vol. 32, No. 5, pp. 273–278). In 1987, Kent Beck and Ward Cunningham began experimenting with the idea of applying patterns to programming – specifically pattern languages – and presented their results at the OOPSLA conference that year. In the following years, Beck, Cunningham and others followed up on this work.
Design patterns gained popularity in computer science after the book Design Patterns: Elements of Reusable Object-Oriented Software was published in 1994 by the so-called "Gang of Four" (Gamma et al.), which is frequently abbreviated as "GoF". That same year, the first Pattern Languages of Programming Conference was held, and the following year th |
https://en.wikipedia.org/wiki/Ground%20pressure | Ground pressure is the pressure exerted on the ground by the tires or tracks of a motorized vehicle, and is one measure of its potential mobility, especially over soft ground. It also applies to the feet of a walking person or machine. Pressure is measured in the SI unit of pascals (Pa). Average ground pressure can be calculated using the standard formula for average pressure: P = F/A. In an idealised case, i.e. a static, uniform net force normal to level ground, this is simply the object's weight divided by contact area. The ground pressure of motorized vehicles is often compared with the ground pressure of a human foot, which can be 60 – 80 kPa while walking or as much as 13 MPa for a person in spike heels.
Increasing the size of the contact area on the ground (the footprint) in relation to the weight decreases the unit ground pressure. Ground pressure of 14 kPa (2 psi) or less is recommended for fragile ecosystems like marshes. Decreasing the ground pressure increases the flotation, allowing easier passage of the body over soft terrain. This is exemplified by use of equipment such as snowshoes.
Examples
All examples are approximate, and will vary based on conditions
Note:
The pressures for average human and horse are for standing still position. A walking human will exert more than double his standing pressure. A galloping horse will exert up to 3.5 MPa (500 psi). The ground pressure for a pneumatic tire is roughly equal to its inflation pressure.
See also
Contact patch
Tire load sensitivity
Related reading
Theory of Ground Vehicles |
https://en.wikipedia.org/wiki/263%20%28number%29 | 263 is the natural number between 262 and 264. It is also a prime number.
In mathematics
263 is
a balanced prime,
an irregular prime,
a Ramanujan prime, a Chen prime, and
a safe prime.
It is also a strictly non-palindromic number and a happy number. |
https://en.wikipedia.org/wiki/Automatic%20acoustic%20management | Automatic acoustic management (AAM) is a method for reducing acoustic emanations in AT Attachment (ATA) mass storage devices for computer data storage, such as ATA hard disk drives and ATAPI optical disc drives. AAM is an optional feature set for ATA/ATAPI devices; when a device supports AAM, the acoustic management parameters are adjustable through a software or firmware user interface.
Details
The ATA/ATAPI sub-command for setting the level of AAM operation is an 8-bit value from 0 to 255. Most modern drives ship with the vendor-defined value of 0x00 in the acoustic management setting. This often translates to the max-performance value of 254 stated in the standard. Values between 128 and 254 (0x80 - 0xFE) enable the feature and select most-quiet to most-performance settings along that range. Though hard drive manufacturers may support the whole range of values, the settings are allowed to be banded, so many values could provide the same acoustic performance.
Although there is no definition of the function implemented to provide acoustic management in the ATA standard, most drives use power control of the head-positioning servo to reduce vibration induced by the head positioning mechanism. Western Digital calls this IntelliSeek™ which uses only enough head acceleration to position the head at the target track and sector "just in time" to access data. Previous seek mechanisms used maximum power and acceleration to position the head. This operation induced the familiar clicking vibration emanating from a seeking hard drive. Western Digital provides a demonstration flash movie illustrating just-in-time head positioning on their web site.
To provide best acoustic performance, some drive manufacturers may limit the maximum seek velocity of the heads for AAM operation. This degrades performance by increasing the average seek time: some head movements are forced to wait an additional disk rotation before accessing data because the head was unable to move to the |
https://en.wikipedia.org/wiki/Common%20disease-common%20variant | The common disease-common variant (often abbreviated CD-CV) hypothesis predicts that common disease-causing alleles, or variants, will be found in all human populations which manifest a given disease. Common variants (not necessarily disease-causing) are known to exist in coding and regulatory sequences of genes. According to the CD-CV hypothesis, some of those variants lead to susceptibility to complex polygenic diseases. Each variant at each gene influencing a complex disease will have a small additive or multiplicative effect on the disease phenotype. These diseases, or traits, are evolutionarily neutral in part because so many genes influence the traits. The hypothesis has held in the case of putative causal variants in apolipoprotein E, including APOE ε4, associated with Alzheimer's disease. IL23R has been found to be associated with Crohn's disease; the at-risk allele has a frequency of 93% in the general population .
One common form of variation across human genomes is called a single nucleotide polymorphism (SNP). As indicated by the name, SNPs are single base changes in the DNA. SNP variants tend to be common in different human populations. These polymorphisms have been valuable as genomic signposts, or "markers", in the search for common variants that influence susceptibility to common diseases. Research has linked common SNPs to diseases such as type 2 diabetes, Alzheimer's, schizophrenia and hypertension.
See also
Rare functional variant |
https://en.wikipedia.org/wiki/Stomach%20oil | Stomach oil is the light oil composed of neutral dietary lipids found in the proventriculus (fore-gut) of birds in the order Procellariiformes. All albatrosses, procellarids (gadfly petrels and shearwaters) and northern and austral storm petrels use the oil. The only Procellariiformes that do not are the diving petrels.
The chemical make up of stomach oil varies from species to species and between individuals, but almost always contains both wax esters and triglycerides. Other compounds found in stomach oil include glycerol ethers, pristane and squalene. Stomach oil has low viscosity and will solidify into a hard wax if allowed to cool.
It was once thought that stomach oil was a secretion of the proventriculus, but it is now known to be a residue of the diet created by digestion of the prey items such as krill, squid, copepods and fish. It is thought to serve several functions for Procellariiformes, primarily as an energy store; its calorific value is around 40 MJ/kg (9.6 kcal per gram), which is only slightly lower than the value for diesel oil. For this reason a great deal more energy can be stored in oil form as opposed to undigested prey. This can be a real advantage for species that range over huge distances to provide food for hungry chicks, or as a store for lean times when ranging across the sea looking for patchy areas of prey.
Surface nesting petrels and albatross can eject this oil out of their mouths (not nostrils, as has sometimes been suggested) towards attacking predators or conspecific rivals. This oil can be deadly to birds, as it can cause matting of the feathers leading to the loss of flight or water repellency. Against threatening mammals (including humans) it is not outright dangerous, but due to its extremely offensive smell it is usually highly repulsive and liable to spoil a predator's hunting success for quite some time. The smell of the hydrophobic oil cannot be removed with water, and can persist (e.g. on clothing) for months or even |
https://en.wikipedia.org/wiki/Master%20of%20Quantitative%20Finance | A master's degree in quantitative finance concerns the application of mathematical methods to the solution of problems in financial economics. There are several like-titled degrees which may further focus on financial engineering, computational finance, mathematical finance, and/or financial risk management.
In general, these degrees aim to prepare students for roles as "quants" (quantitative analysts), including analysis, structuring, trading, and investing; in particular, these degrees emphasize derivatives and fixed income, and the hedging and management of the resultant market and credit risk.
Formal master's-level training in quantitative finance has existed since 1990.
Structure
The program is usually one to one and a half years in duration, and may include a thesis component. Entrance requirements are generally multivariable calculus, linear algebra, differential equations and some exposure to computer programming (usually C++); programs emphasizing financial mathematics may require some background in measure theory.
Initially, the curriculum builds quantitative skills, and simultaneously develops the underlying finance theory:
The quantitative component draws on applied mathematics, computer science and statistical modelling, and emphasizes stochastic calculus, numerical methods and simulation techniques; see . Some programs also focus on econometrics / time series analysis.
The theory component usually includes a formal study of financial economics, addressing asset pricing and financial markets; some programs may also include general coverage of economics, accounting, corporate finance and portfolio management.
The components are then integrated, addressing the modelling, valuation and hedging of equity derivatives, commodity derivatives, foreign exchange derivatives, and fixed income instruments and their related credit- and interest rate derivatives; see .
Programs often include dedicated modules in market risk and credit risk, with some degree |
https://en.wikipedia.org/wiki/Social%20selection | Social selection is a term used with varying meanings in biology.
Joan Roughgarden proposed a hypothesis called social selection as an alternative to sexual selection. Social selection is argued to be a mode of natural selection based on reproductive transactions and a two-tiered approach to evolution and the development of social behavior. Reproductive transactions refer to a situation where one organism offers assistance to another in exchange for access to reproductive opportunity. The two tiers of the theory are behavioral and population genetic. The genetic aspect states that anisogamy arose to maximize contact rate between gametes. The behavioral aspect is concerned with cooperative game theory and the formation of social groups to maximize the production of offspring. In her critique against the neo-Darwinian defense of sexual selection, Roughgarden outlines exceptions to many of the assumptions that come with sexual selection. These exceptions include sexually monomorphic species, species which reverse standard sex roles, species with template multiplicity, species with transgender presentation, frequencies of homosexual mating, and the lack of correlation between sexually selected traits and deleterious mutation.
An article published by Roughgarden's lab on her ideas received criticism in the journal Science. Forty scientists produced ten critical letters. The critics stated that the article was misleading, that it contained misunderstandings and misrepresentations, that sexual selection accounted for all the data presented and subsumed Roughgarden's theoretical analysis, and that sexual selection explained data that her theory could not.
Other researchers, such as biologist Mary Jane West-Eberhard and evolutionary medicine researcher Randolph M. Nesse, instead view sexual selection as a subcategory of social selection, with Nesse and anthropologist Christopher Boehm arguing further that altruism in humans held fitness advantages that enabled evolutionar |
https://en.wikipedia.org/wiki/Bite%20force%20quotient | Bite force quotient (BFQ) is a numerical value commonly used to represent the bite force of an animal, while also taking factors like the animal's size into account.
The BFQ is calculated as the regression of the quotient of an animal's bite force in newtons divided by its body mass in kilograms. The BFQ was first applied by Wroe et al. (2005) in a paper comparing bite forces, body masses and prey size in a range of living and extinct mammalian carnivores, later expanded on by Christiansen & Wroe (2007). Results showed that predators that take relatively large prey have large bite forces for their size, i.e., once adjusted for allometry. The authors predicted bite forces using beam theory, based on the directly proportional relationship between muscle cross-sectional area and the maximal force muscles can generate. Because body mass is proportional to volume the relationship between bite force and body mass is allometric. All else being equal, it would be expected to follow a 2/3 power rule. Consequently, small species would be expected to bite harder for their size than large species if a simple ratio of bite force to body mass is used, resulting in bias. Applying the BFQ normalizes the data allowing for fair comparison between species of different sizes in much the same way as an encephalization quotient normalizes data for brain size to body mass comparisons. It is a means for comparison, not an indicator of absolute bite force. In short, if an animal or species has a high BFQ this indicates that it bites hard for its size after controlling for allometry.
Hite et al., who include data from the widest range of living mammals of any bite force regression to date, produce from their regression the BFQ equation:
where BF = Bite Force (N), and BM = Body Mass (g)
Carnivore BFQs
Table sources (unless otherwise stated): |
https://en.wikipedia.org/wiki/RR%20Media | RR Media was a NASDAQ listed provider of global digital media services to the broadcast industry and content owners. Its services can be divided into four main groups: global content distribution network (satellite, fiber and the internet); content management & playout; sports, news & live events; and online video services.
The company was rebranded to RR Media from RRsat in September 2014.
In February 2016, it was announced that, subject to regulatory approvals, RR Media was to be acquired by SES, based in Betzdorf, Luxembourg, and merged with SES subsidiary company, SES Platform Services a media services provider for television broadcasters, production companies and platform operators, based in Unterföhring near Munich, Germany. In July 2016, the merged company was named MX1.
Digital media services
Global content distribution services RR Media's global distribution network uses a combination of satellite, fiber and the internet. The network includes satellite downlink and uplink; fiber connectivity to digital media hubs; connectivity to TV service providers; and internet-based content delivery. RR Media's network delivers live television channels, streaming media and Video on demand (VOD) content in all formats including Standard-definition television (SD), High-definition television (HD), 4K resolution (4K) & 3D television (3D).
End-to-end content management & playout services RR Media manages, prepares and plays out content from its media centers. Services include: content preparation (digitization, localization, conversion, ingest, multiple formatting, editing, restoration); content management (digital asset management, media ingest and library, streamlined workflows, metadata curation, Video on demand (VOD) delivery) and playout, channel creation, playlist management, advertising insertion/management, graphics, titles & overlay, live events operations). RR Media also creates branded or white label product television channels using live and archived materi |
https://en.wikipedia.org/wiki/Caldithrix | Caldithrix is a genus of thermophilic and anaerobic bacteria, currently assigned to its own phylum. |
https://en.wikipedia.org/wiki/COLT%20%28software%29 | COLT (Code Orchestra Livecoding Tool) is an ActionScript and JavaScript livecoding tool by Code Orchestra, available by subscription. As of 2019 it appears to be abandoned; the last activity in GitHub was 2015, and the domain name has been purchased by spammers.
History
The first version of COLT was released in May 2013, and at the time was the first available livecoding tool for the ActionScript Language. Further minor updates included mobile development support using Adobe AIR technology for iOS and Android devices. Version 1.1 included an upgraded Flex compiler boasting up to 3x compilation speed increase and allowed using the compiler bundled with an application as an external compiler for ActionScript IDEs using an external API. Version 1.2 featured JavaScript support and a completely reworked user interface.
Features
IDE integration
COLT is a separate tool that can be used with any IDE unlike most livecoding tools that limit a user to usage of a specific development environment. A code/resource routine is triggered on alteration of a file within COLT's project configured paths. It also provides an external API providing methods to export a project, run livecoding sessions and production build routines, etc. to ease the IDE integration.
Code Protection
To prevent an application from hanging or crashing due to the possible mistypes during live code updates, COLT manages to protect the running application from the following potentially dangerous cases:
Illegal syntax
Runtime errors
Infinite loops/recursions
Languages
Version 1.2.2 includes support for ActionScript and JavaScript programming languages
ActionScript
Runtime modifying and adding of fields, methods and classes
Runtime updates of asset resources
Adobe AIR support for iOS and Android livecoding
Higher-performance Flex compiler
JavaScript
Runtime modifying and adding of functions and variables
Runtime updates of asset resources
Live Reload capabilities (refreshing a browser page on |
https://en.wikipedia.org/wiki/Campylobacter | Campylobacter is a type of bacteria that can cause a diarrhea disease in people. Its name means "curved bacteria", as the germ typically appears in a comma or "s" shape. According to its scientific classification, it is a genus of gram-negative bacteria that is motile.
The germ is common in nature and in domestic animals. It is frequently found in raw food of vegetable and animal origin. Its numbers can be very high in some foods, like raw poultry. Due to their diverse natural reservoir, some Campylobacter can also be detected in the air, although not in an epidemiological significance. The disease that some of the species of the bacteria can cause is called campylobacteriosis.
At least a dozen species of Campylobacter have been implicated in human disease, with C. jejuni (80–90%) and C. coli (5-10%) being the most common. C. jejuni is recognized as one of the main causes of bacterial foodborne disease in many developed countries. It is the number one cause of bacterial gastroenteritis in Europe, with over 246,000 cases confirmed annually. C. jejuni infection can also cause bacteremia in immunocompromised people, while C. lari is a known cause of recurrent diarrhea in children. C. fetus can cause spontaneous abortions in cattle and sheep, and is an opportunistic pathogen in humans.
Morphology and Phenotype
Campylobacter spp. generally appear as curved or comma-shaped rods, and are able to move via unipolar or bipolar flagella. They grow best between 37–42 °C in a microaerophilic environment. When exposed to atmospheric oxygen, C. jejuni is able to change into a coccus form. Most species of Campylobacter are positive by the oxidase test and catalase test and are able to reduce nitrate. The number of known quinolone-resistant Campylobacter strains is growing. It is suggested that this is caused by the overuse of quinolone antibiotics in animal agriculture.
History
Theodor Escherich was the first to describe in 1886 what are known today as Campylobacters i |
https://en.wikipedia.org/wiki/Facing%20Identification%20Mark | The Facing Identification Mark, or FIM, is a bar code designed by the United States Postal Service to assist in the automated processing of mail. The FIM is a set of vertical bars printed on the envelope or postcard near the upper edge, just to the left of the postage area (the area where the postage stamp or its equivalent is placed). The FIM is intended for use primarily on preprinted envelopes and postcards and is applied by the company printing the envelopes or postcards, not by the USPS.
The FIM is a nine-bit code consisting of ones (vertical bars) and zeroes (blank spaces). The following five codes are in use:
FIM A: || | || (110010011)
FIM B: | || || | (101101101)
FIM C: || | | || (110101011)
FIM D: ||| | ||| (111010111)
FIM E: | | | | (101000101)
All defined FIMs start and end with a bar, and are palindromic, reading the same forward and backward. Thus, there are only 16 possible FIMs, 11 if the current limits of at most 3 consecutive bars or spaces are maintained.
The FIM allows the proper facing of mail for cancellation. It also identifies the manner in which postage is paid (e.g., business reply mail or Information Based Indicia (IBI) postage) and whether that business reply mail has a barcode, typically an Intelligent Mail Barcode or the older POSTNET barcode. If the barcode is present, the mail can be sent directly to a sorter.
The five codes have the following uses:
FIM A is used for mail bearing regular postage and an Intelligent Mail Barcode. It is commonly used by preprinted courtesy reply mail and metered reply mail, but may be applied to any mail to speed delivery.
FIM B is used for business reply mail without a preprinted barcode. Because this costs more than barcoded mail, it is rarely used.
FIM C is used for business reply mail with a preprinted Intelligent Mail Barcode.
FIM D is used only with IBI postage.
FIM E is used to mark Share Mail, where the Intelligent Mail Barcode is used as postage. |
https://en.wikipedia.org/wiki/Soboleva%20modified%20hyperbolic%20tangent | The Soboleva modified hyperbolic tangent, also known as (parametric) Soboleva modified hyperbolic tangent activation function ([P]SMHTAF), is a special S-shaped function based on the hyperbolic tangent, given by
History
This function was originally proposed as "modified hyperbolic tangent" by Ukrainian scientist Elena V. Soboleva () as a utility function for multi-objective optimization and choice modelling in decision-making.
Practical usage
The function has since been introduced into neural network theory and practice.
It was also used in economics for modelling consumption and investment, to approximate current-voltage characteristics of field-effect transistors and light-emitting diodes, to design antenna feeders, and analyze plasma temperatures and densities in the divertor region of fusion reactors.
Sensitivity to parameters
Derivative of the function is defined by the formula:
The following conditions are keeping the function limited on y-axes: a ≤ c, b ≤ d.
A family of recurrence-generated parametric Soboleva modified hyperbolic tangent activation functions (NPSMHTAF, FPSMHTAF) was studied with parameters a = c and b = d. It is worth noting that in this case, the function is not sensitive to flipping the left and right-sides parameters:
The function is sensitive to ratio of the denominator coefficients and often is used without coefficients in the numerator:
With parameters a = b = c = d = 1 the modified hyperbolic tangent function reduces to the conventional tanh(x) function, whereas for a = b = 1 and c = d = 0, the term becomes equal to sinh(x).
See also
Activation function
e (mathematical constant)
Equal incircles theorem, based on sinh
Hausdorff distance
Inverse hyperbolic functions
List of integrals of hyperbolic functions
Poinsot's spirals
Sigmoid function
Notes |
https://en.wikipedia.org/wiki/Gravitational%20energy | Gravitational energy or gravitational potential energy is the potential energy a massive object has in relation to another massive object due to gravity. It is the potential energy associated with the gravitational field, which is released (converted into kinetic energy) when the objects fall towards each other. Gravitational potential energy increases when two objects are brought further apart.
Formulation
For two pairwise interacting point particles, the gravitational potential energy is given by
where and are the masses of the two particles, is the distance between them, and is the gravitational constant.
Close to the Earth's surface, the gravitational field is approximately constant, and the gravitational potential energy of an object reduces to
where is the object's mass, is the gravity of Earth, and is the height of the object's center of mass above a chosen reference level.
Newtonian mechanics
In classical mechanics, two or more masses always have a gravitational potential. Conservation of energy requires that this gravitational field energy is always negative, so that it is zero when the objects are infinitely far apart. The gravitational potential energy is the potential energy an object has because it is within a gravitational field.
The force between a point mass, , and another point mass, , is given by Newton's law of gravitation:
To get the total work done by an external force to bring point mass from infinity to the final distance (for example the radius of Earth) of the two mass points, the force is integrated with respect to displacement:
Because , the total work done on the object can be written as:
In the common situation where a much smaller mass is moving near the surface of a much larger object with mass , the gravitational field is nearly constant and so the expression for gravitational energy can be considerably simplified. The change in potential energy moving from the surface (a distance from the center) to a height |
https://en.wikipedia.org/wiki/Pierolapithecus | Pierolapithecus catalaunicus is an extinct species of primate which lived around 12.5-13 million years ago during the Miocene in what is now Hostalets de Pierola, Catalonia, Spain. Some researchers believe that it is a candidate for common ancestor to the great ape clade, or is at least closer than any previous fossil discovery. Others suggest it being a pongine, or a dryopith. On 16 October 2023, scientists reported the facial reconstruction of the great ape.
History
The splanchnocranium was discovered in 2002 and systematic excavations took place during May and June 2003. The species was described by a team of Spanish paleoanthropologists led by Salvador Moyà-Solà on the basis of a fossil skeleton, IPS21350 (nicknamed Pau ("peace" in Catalan as it was announced alongside Spanish demonstrations against the Iraq War)), discovered in December 2002. The finding was first reported in the journal Science on November 19, 2004. The skeleton is of an adult male individual, composed of 83 bones that make up the splanchnocranium, both maxillae, a complete set of cheek teeth, both canines, a right central incisor, zygomatics, lacrimals, a partial frontal, carpals, metacarpals, manual phalanges from two hands, tarsals, metatarsals, pedal phalanges, right patellar distal epiphysis, a left radius, some long bone diaphyses, two pelvic pieces, three vertebrae, two intact ribs, and twelve rib fragments of large size. They named their new genus after the nearby village Els Hostalets de Pierola, and Catalonia respectively.
Description
Moyà-Solà et al. initially founded the species on a set of unique characteristics, of which are the following. The frontal processes of the face remain on the same plane, the nasals are flat and sit beneath the lower rims of the orbit, the glabella is posteriorly oriented, the face is low, the brows are thin, the zygomatic root is high, and the nasoalveolar clivus is high. The rear border of the incisive foramen is in line with the P3, the palate is |
https://en.wikipedia.org/wiki/Szarvas%20inscription | The Szarvas inscription refers to the inscription on a bone needle case found near Szarvas in southeastern Hungary and dating from the second half of the 8th century, the "Late Avar" period (700-791).
The needle case and its inscription
The name of the script of the Szarvas inscription
The Hungarian archeologist, historian and linguist Gábor Vékony named the script used on the needle case as "Kárpát-medencei rovásírás" ("Carpathian Basin Rovas script"). He often used this term in his book, A székely írás emlékei, kapcsolatai, története, e.g. in the chapter "A kárpát-medencei rovásábécé korabeli feljegyzése" ("The contemporary record of the Carpathian Basin Rovas alphabet").
Vékony analysed the similarities and the differences between the Old Hungarian and the Carpathian Basin scripts on page 154 of his book. On page 232, Vékony wrote: "- Aethicus Ister jelei azonosak az egykori Kárpát-medencei rovásírás jeleivel." ("The symbols of Aethicus Ister are identical to the symbols of the quondam Carpathian Basin script").
Vékony also writes : "E jel a Szarvason azonosított Kárpát-medencei f alig torzult megfelelője..." ("This symbol is identical to the Carpathian Basin 'f' identified in Szarvas". (referring to the bone needle case found in Szarvas)
In page 233, Vékony writes: "Erre utalhat az is, hogy ez a betűalak levezethető egy párthus alep formából. Feltehető tehát ennek a jelnek a megléte a Kárpát-medencei rovásírásban is (a székelybe is innen származhatott)." ("This could imply also that this glyph can be derived from the Parthian Aleph form. Consequently, the existence of this symbol can be supposed in the Carpathian Basin script as well (it could originate from this to the Székely)." Here the 'Szekely' refers to the Szekely-Hungarian Rovas script also known as Old Hungarian script. Vékony's writing suggests a proposal that a Carpathian Basin Rovas script may be one of the ancestors of the Szekely-Hungarian Rovas script.
The meaning of the inscription
Gábor V |
https://en.wikipedia.org/wiki/List%20of%20common%20coordinate%20transformations | This is a list of some of the most commonly used coordinate transformations.
2-dimensional
Let be the standard Cartesian coordinates, and the standard polar coordinates.
To Cartesian coordinates
From polar coordinates
From log-polar coordinates
By using complex numbers , the transformation can be written as
That is, it is given by the complex exponential function.
From bipolar coordinates
From 2-center bipolar coordinates
From Cesàro equation
To polar coordinates
From Cartesian coordinates
Note: solving for returns the resultant angle in the first quadrant (). To find one must refer to the original Cartesian coordinate, determine the quadrant in which lies (for example, (3,−3) [Cartesian] lies in QIV), then use the following to solve for
The value for must be solved for in this manner because for all values of , is only defined for , and is periodic (with period ). This means that the inverse function will only give values in the domain of the function, but restricted to a single period. Hence, the range of the inverse function is only half a full circle.
Note that one can also use
From 2-center bipolar coordinates
Where 2c is the distance between the poles.
To log-polar coordinates from Cartesian coordinates
Arc-length and curvature
In Cartesian coordinates
In polar coordinates
3-dimensional
Let (x, y, z) be the standard Cartesian coordinates, and (ρ, θ, φ) the spherical coordinates, with θ the angle measured away from the +Z axis (as , see conventions in spherical coordinates). As φ has a range of 360° the same considerations as in polar (2 dimensional) coordinates apply whenever an arctangent of it is taken. θ has a range of 180°, running from 0° to 180°, and does not pose any problem when calculated from an arccosine, but beware for an arctangent.
If, in the alternative definition, θ is chosen to run from −90° to +90°, in opposite direction of the earlier definition, it can be found uniquely from an arcsine, but beware of an arccota |
https://en.wikipedia.org/wiki/Porosity | Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure the "accessible void", the total amount of void space accessible from the surface (cf. closed-cell foam).
There are many ways to test porosity in a substance or part, such as industrial CT scanning.
The term porosity is used in multiple fields including pharmaceutics, ceramics, metallurgy, materials, manufacturing, petrophysics, hydrology, earth sciences, soil mechanics, rock mechanics, and engineering.
Void fraction in two-phase flow
In gas-liquid two-phase flow, the void fraction is defined as the fraction of the flow-channel volume that is occupied by the gas phase or, alternatively, as the fraction of the cross-sectional area of the channel that is occupied by the gas phase.
Void fraction usually varies from location to location in the flow channel (depending on the two-phase flow pattern). It fluctuates with time and its value is usually time averaged. In separated (i.e., non-homogeneous) flow, it is related to volumetric flow rates of the gas and the liquid phase, and to the ratio of the velocity of the two phases (called slip ratio).
Porosity in earth sciences and construction
Used in geology, hydrogeology, soil science, and building science, the porosity of a porous medium (such as rock or sediment) describes the fraction of void space in the material, where the void may contain, for example, air or water. It is defined by the ratio:
where VV is the volume of void-space (such as fluids) and VT is the total or bulk volume of material, including the solid and void components. Both the mathematical symbols and are used to denote porosity.
Porosity is a fraction between 0 and 1, typically ranging from less than 0.005 for solid granite to more than 0.5 for peat and clay.
The porosity of a rock, or sedimenta |
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