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https://en.wikipedia.org/wiki/X86%20debug%20register
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On the x86 architecture, a debug register is a register used by a processor for program debugging. There are six debug registers, named DR0...DR7, with DR4 and DR5 as obsolete synonyms for DR6 and DR7. The debug registers allow programmers to selectively enable various debug conditions associated with a set of four debug addresses.
Two of these registers are used to control debug features. These registers are accessed by variants of the MOV instruction. A debug register may be either the source operand or destination operand. The debug registers are privileged resources; the MOV instructions that access them can only be executed at privilege level zero. An attempt to read or write the debug registers when executing at any other privilege level causes a general protection fault.
DR0 to DR3
Each of these registers contains the linear address associated with one of four breakpoint conditions. Each breakpoint condition is further defined by bits in DR7.
The debug address registers are effective whether or not paging is enabled. The addresses in these registers are linear addresses. If paging is enabled, the linear addresses are translated into physical addresses by the processor's paging mechanism. If paging is not enabled, these linear addresses are the same as physical addresses.
Note that when paging is enabled, different tasks may have different linear-to-physical address mappings. When this is the case, an address in a debug address register may be relevant to one task but not to another. For this reason the x86 has both global and local enable bits in DR7. These bits indicate whether a given debug address has a global (all tasks) or local (current task only) relevance.
DR6 - Debug status
The debug status register permits the debugger to determine which debug conditions have occurred. When the processor detects an enabled debug exception, it will set the corresponding bits of this register before entering the debug exception handler.
DR7 - Debug control
The de
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https://en.wikipedia.org/wiki/Interosseous%20sacroiliac%20ligament
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The interosseous sacroiliac ligament, also known as the axial interosseous ligament, is a ligament of the sacroiliac joint that lies deep to the posterior ligament. It connects the tuberosities of the sacrum and the ilium of the pelvis.
Structure
The interosseous sacroiliac ligament consists of a series of short, strong fibers connecting the tuberosities of the sacrum and ilium. It is one of the strongest ligaments in the body.
Function
The major function of the interosseous sacroiliac ligament is to keep the sacrum and ilium together. This prevents abduction or distraction of the sacroiliac joint. It also helps to bear the weight of the thorax, upper limbs, head, and neck. This is performed by the nearly horizontal direction of the fibers running perpendicular from the sacrum to the ilium.
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https://en.wikipedia.org/wiki/Flags%20of%20Africa
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These are the various flags of Africa.
Supranational and international flags
An incomplete list of flags representing all African international and supranational organisations, which omits intercontinental organisations such as the United Nations:
Flags of African sovereign states
Disputed or partially recognised states
Flags of African dependencies
Flags of African subdivisions
Angola
Comoros
Egypt
Ethiopia
Kenya
Liberia
Nigeria
São Tomé and Príncipe
Somalia
South Africa
Tanzania
Flags of African cities
Flags of cities with over 1 million inhabitants.
Ethnic flags
Historical flags
{| class="wikitable"
|-
! style="width:100px;"|Flag !! style="width:100px;"|Date !! style="width:200px;"|Use !! style="width:700px;"|Description
|-
| || 2012–2013 || Flag of Azawad ||
|-
| || 1975–1990 || Flag of the People's Republic of Benin ||
|-
| || 1967 || Flag of the Republic of Benin ||
|-
| || 1967–1970 || Flag of the Republic of Biafra ||
|-
| || 1962–1966 || Flag of the Kingdom of Burundi ||
|-
| || 1966 || Flag of the Republic of Burundi ||
|-
| || 1966–1967 || Flag of the Republic of Burundi ||
|-
| || 1967–1982 || Flag of the Republic of Burundi ||
|-
| || 1922–1961 || Flag of British Cameroon ||
|-
| || 1957–1961 || Flag of Cameroon ||
|-
| || 1961–1975 || Flag of Cameroon ||
|-
| || 1876–1910 || Flag of the Cape Colony ||
|-
| || 1975–1992 || Flag of Cape Verde ||
|-
| || 1963–1975 || Flag of the Comoros ||
|-
| || 1975–1978 || Flag of the Comoros ||
|-
| || 1978–1992 || Flag of the Comoros ||
|-
| || 1992–1996 || Flag of the Comoros ||
|-
| || 1996–2001 || Flag of the Comoros ||
|-
| || 1885–1960 || Flag of the Congo Free State / the Belgian Congo ||
|-
| || 1960–1963 || Flag of Congo-Léopoldville ||
|-
| || 1963–1966 || Flag of Congo-Léopoldville / the Democratic Republic of the Congo ||
|-
| || 1966–1971 || Flag of the Democratic Republic of the Congo ||
|-
| || 1997–2003 || Flag of the Democratic Republic of the Congo ||
|-
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https://en.wikipedia.org/wiki/Inferior%20tibiofibular%20joint
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The inferior tibiofibular joint, also known as the distal tibiofibular joint (tibiofibular syndesmosis), is formed by the rough, convex surface of the medial side of the distal end of the fibula, and a rough concave surface on the lateral side of the tibia.
Below, to the extent of about 4 mm, these surfaces are smooth and covered with cartilage, which is continuous with that of the ankle joint.
The ligaments are:
Anterior ligament of the lateral malleolus
Posterior ligament of the lateral malleolus
Interosseous membrane of leg
The inferior transverse ligament of the tibiofibular syndesmosis is included in older versions of Gray's Anatomy, but not in Terminologia Anatomica. However, it still appears in some anatomy textbooks.
It should not be confused with the superior tibiofibular joint, which is the only synovial tibiofibular joint, and is sometimes simply called the "tibiofibular articulation".
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https://en.wikipedia.org/wiki/Superior%20tibiofibular%20joint
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The superior tibiofibular articulation (also called proximal tibiofibular joint) is an arthrodial joint between the lateral condyle of tibia and the head of the fibula.
The contiguous surfaces of the bones present flat, oval facets covered with cartilage and connected together by an articular capsule and by anterior and posterior cruciate ligaments.
When the term tibiofibular articulation is used without a modifier, it refers to the proximal, not the distal (i.e., inferior) tibiofibular articulation.
Clinical significance
Injuries to the proximal tibiofibular joint are uncommon and usually associated with other injuries to the lower leg. Dislocations can be classified into the following five types:
Anterolateral dislocation (most common)
Posteromedial dislocation
Superior dislocation (uncommon, associated with shortened tibia fractures or severe ankle injuries)
Inferior dislocation (rare, associated with lengthened tibia fractures or avulsion of the foot, usually extensive soft tissue injury and poor prognosis)
Chronic instability (subluxation)
As there are often concomitant fractures and ligamentous injuries (e.g., ankle fracture), anterolateral and posteromedial dislocations may be overlooked on first examination, with the potential to cause chronic instability. If the dislocation is recognized and treated properly, prognosis is typically good, although injury to the common peroneal nerve may occur. Inferior dislocations are exceptional as they usually only occur in avulsion (traumatic amputation) injuries. Subluxation may also occur in diseases with ligamentous laxity (e.g., Ehlers-Danlos Syndrome), muscle weakness (e.g., muscular dystrophy), or secondarily to degeneration (e.g., in rheumatoid arthritis).
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https://en.wikipedia.org/wiki/Posterior%20ligament%20of%20the%20head%20of%20the%20fibula
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The posterior ligament of the head of the fibula is a part of the knee. It is a single thick and broad band, which passes obliquely upward from the back of the head of the fibula to the back of the lateral condyle of the tibia.
It is covered by the tendon of the Popliteus.
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https://en.wikipedia.org/wiki/Anterior%20tibiofibular%20ligament
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The anterior ligament of the lateral malleolus (anterior tibiofibular ligament or anterior inferior ligament) is a flat, trapezoidal band of fibers, broader below than above, which extends obliquely downward and lateralward between the adjacent margins of the tibia and fibula, on the front aspect of the syndesmosis.
It is in relation, in front, with the fibularis tertius, the aponeurosis of the leg, and the integument; behind, with the interosseous ligament; and lies in contact with the cartilage covering the talus.
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https://en.wikipedia.org/wiki/Multimedia%20over%20Coax%20Alliance
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The Multimedia over Coax Alliance (MoCA) is an international standards consortium that publishes specifications for networking over coaxial cable. The technology was originally developed to distribute IP television in homes using existing cabling, but is now used as a general-purpose Ethernet link where it is inconvenient or undesirable to replace existing coaxial cable with optical fiber or twisted pair cabling.
MoCA 1.0 was approved in 2006, MoCA 1.1 in April 2010, MoCA 2.0 in June 2010, and MoCA 2.5 in April 2016. The most recently released version of the standard, MoCA 3.0, supports speeds of up to .
Membership
The Alliance currently has 45 members including pay TV operators, OEMs, CE manufacturers and IC vendors.
MoCA's board of directors consists of Arris, Comcast, Cox Communications, DirecTV, Echostar, Intel, InCoax, MaxLinear and Verizon.
Technology
Within the scope of the Internet protocol suite, MoCA is a protocol that provides the link layer. In the 7-layer OSI model, it provides definitions within the data link layer (layer 2) and the physical layer (layer 1). DLNA approved of MoCA as a layer 2 protocol. A MoCA network can contain up to 16 nodes for MoCA 1.1 and higher, with a maximum of 8 for MoCA 1.0. The network provides a shared-medium, half-duplex link between all nodes using time-division multiplexing; within each timeslot, any pair of nodes communicates directly with each other using the highest mutually-supported version of the standard.
Versions
MoCA 1.0 The first version of the standard, MoCA 1.0, was ratified in 2006 and supports transmission speeds of up to 135 Mb/s.
MoCA 1.1 MoCA 1.1 provides 175 Mbit/s net throughputs (275 Mbit/s PHY rate) and operates in the 500 to 1500 MHz frequency range.
MoCA 2.0 MoCA 2.0 offers actual throughputs (MAC rate) up to 1 Gbit/s. Operating frequency range is 500 to 1650 MHz. Packet error rate is 1 packet error in 100 million. MoCA 2.0 also offers lower power modes of sleep and standby and is backw
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https://en.wikipedia.org/wiki/Araucania%20%28wasp%29
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Araucania is an invalid genus of braconid wasps in the family Braconidae, found in South America. There are at least two described species in Araucania.
The valid genus Araucania Pate 1947, in the family Sapygidae, has nomenclatural precedence over the braconid name, published in 1993, so the latter name must be replaced, following the International Code of Zoological Nomenclature Article 52.2.
Species
Araucania maculipennis Marsh, 1993
Araucania penai Marsh, 1993
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https://en.wikipedia.org/wiki/Inferior%20transverse%20ligament%20of%20the%20tibiofibular%20syndesmosis
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The inferior transverse ligament of the tibiofibular syndesmosis is a connective tissue structure in the lower leg that lies in front of the posterior ligament. It is a strong, thick band, of yellowish fibers which passes transversely across the back of the ankle joint, from the lateral malleolus to the posterior border of the articular surface of the tibia, almost as far as its malleolar process.
This ligament projects below the margin of the bones, and forms part of the articulating surface for the talus.
It is not included in Terminologia Anatomica, but it still appears in some anatomy textbooks.
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https://en.wikipedia.org/wiki/Superghost
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For the game, see Lexicant, a variant of ghost (game).
In a supersymmetric quantum field theory, a superghost is a fermionic Faddeev–Popov ghost, which is used in the gauge fixing of a fermionic symmetry generator.
Supersymmetric quantum field theory
String theory
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https://en.wikipedia.org/wiki/Posterior%20tibiofibular%20ligament
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The posterior ligament of the lateral malleolus (posterior tibiofibular ligament, posterior inferior ligament) is smaller than the anterior ligament of the lateral malleolus and is disposed in a similar manner on the posterior surface of the syndesmosis. It connects the tibia and fibular on the inferior part of both bones.
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https://en.wikipedia.org/wiki/Sacrococcygeal%20symphysis
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The sacrococcygeal symphysis (sacrococcygeal articulation, articulation of the sacrum and coccyx) is an amphiarthrodial joint, formed between the oval surface at the apex of the sacrum, and the base of the coccyx.
It is a slightly moveable joint which is frequently, partially or completely, obliterated in old age, homologous with the joints between the bodies of the vertebrae.
Structure
Articular disc
The sacrococcygeal disc or interosseus ligament is similar to the intervertebral discs but thinner, thicker in front and behind than at the sides, and with a firmer texture. The articular surfaces are elliptical with longer transversal axes. The surface on the sacrum is convex and that on the coccyx concave. Occasionally the coccyx is freely movable on the sacrum, most notably during pregnancy; in such cases a synovial membrane is present.
Ligaments
The joint is strengthened by a series of ligaments:
The ventral or anterior sacrococcygeal ligament is an extension of the anterior longitudinal ligament (ALL) that runs down along the spine on the anterior sides of the bodies of the vertebrae. It consists of a few irregular fibers that attach to the anterior sides of the sacrum and coccyx and blend with the periosteum.
The dorsal or posterior sacrococcygeal ligament has a deep and a superficial part:
The deep dorsal ligament is a flat band which corresponds to the posterior longitudinal ligament (PLL) that run down inside the vertebral canal on the posterior surfaces of the bodies of the vertebrae. From the posterior side of the fifth sacral body inside the sacral canal, the dorsal ligament stretches to the posterior side of the coccyx, to attach deep to the superficial dorsal ligament.
The superficial dorsal ligament corresponds to the ligamenta flava and closes the posterior aspect of the distal end of the vertebral canal. It stretches from median sacral crest and the free margin of the sacral hiatus to the dorsal surface of the coccyx.
The lateral sacro
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https://en.wikipedia.org/wiki/Condyloid%20joint
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A condyloid joint (also called condylar, ellipsoidal, or bicondylar) is an ovoid articular surface, or condyle that is received into an elliptical cavity. This permits movement in two planes, allowing flexion, extension, adduction, abduction, and circumduction.
Examples
Examples include:
the wrist-joint
metacarpophalangeal joints
metatarsophalangeal joints
atlanto-occipital joints
These are also called ellipsoid joints. The oval-shaped condyle of one bone fits into the elliptical cavity of the other bone. These joints allow biaxial movements — i.e., forward and backward, or from side to side, but not rotation. Radiocarpal joint and Metacarpo-phalangeal joint are examples of condyloid joints.
An example of an Ellipsoid joint is the wrist; it functions similarly to the ball and socket joint except is unable to rotate 360 degrees; it prohibits axial rotation.
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https://en.wikipedia.org/wiki/Saddle%20joint
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A saddle joint (sellar joint, articulation by reciprocal reception) is a type of synovial joint in which the opposing surfaces are reciprocally concave and convex. It is found in the thumb, the thorax, the middle ear, and the heel.
Structure
In a saddle joint, one bone surface is concave while another is convex. This creates significant stability.
Movements
The movements of saddle joints are similar to those of the condyloid joint and include flexion, extension, adduction, abduction, and circumduction. However, axial rotation is not allowed. Saddle joints are said to be biaxial, allowing movement in the sagittal and frontal planes.
Examples of saddle joints in the human body include the carpometacarpal joint of the thumb, the sternoclavicular joint of the thorax, the incudomalleolar joint of the middle ear, and the calcaneocuboid joint of the heel.
Name
The term "saddle" arises because the concave-convex bone interaction is compared to a horse rider riding a horse, with both bone surfaces being saddle-shaped. The saddle joint is also known as the sellar joint.
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https://en.wikipedia.org/wiki/Pivot%20joint
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In animal anatomy, a pivot joint (trochoid joint, rotary joint or lateral ginglymus) is a type of synovial joint whose movement axis is parallel to the long axis of the proximal bone, which typically has a convex articular surface.
According to one classification system, a pivot joint like the other synovial joint —the hinge joint has one degree of freedom. Note that the degrees of freedom of a joint is not the same as the same as joint's range of motion.
Movements
Pivot joints allow for rotation, which can be external (for example when rotating an arm outward), or internal (as in rotating an arm inward). When rotating the forearm, these movements are typically called pronation and supination. In the standard anatomical position, the forearms are supinated, which means that the palms are facing forward, and the thumbs are pointing away from the body. In contrast, a forearm in pronation would have the palm facing backward and the thumb would be closer to the body, pointing medially.
Examples
Examples of a pivot joint include:
Proximal radioulnar joint
Distal radioulnar joint
Median atlanto-axial joint
In contrast, spherical joints (or ball and socket joints) such as the hip joint permit rotation and all other directional movement, while pivot joints only permit rotation.
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https://en.wikipedia.org/wiki/Plane%20joint
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A plane joint (arthrodial joint, gliding joint, plane articulation) is a synovial joint which, under physiological conditions, allows only gliding movement.
Plane joints permit sliding movements in the plane of articular surfaces. The opposed surfaces of the bones are flat or almost flat, with movement limited by their tight joint capsules. Based only on their shape, plane joints can allow multiple movements, including rotation. Thus plane joints can be functionally classified as multiaxial joints. Plane joints are numerous and are nearly always small, such as the acromioclavicular joint between the acromion of the scapula and the clavicle. Typically, they are found in the wrists, ankles, the 2nd through 7th sternocostal joints, vertebral transverse and spinous processes.
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https://en.wikipedia.org/wiki/Progenitor%20cell
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A progenitor cell is a biological cell that can differentiate into a specific cell type. Stem cells and progenitor cells have this ability in common. However, stem cells are less specified than progenitor cells. Progenitor cells can only differentiate into their "target" cell type. The most important difference between stem cells and progenitor cells is that stem cells can replicate indefinitely, whereas progenitor cells can divide only a limited number of times. Controversy about the exact definition remains and the concept is still evolving.
The terms "progenitor cell" and "stem cell" are sometimes equated.
Properties
Most progenitors are identified as oligopotent. In this point of view, they can compare to adult stem cells, but progenitors are said to be in a further stage of cell differentiation. They are "midway" between stem cells and fully differentiated cells. The kind of potency they have depends on the type of their "parent" stem cell and also on their niche. Some research found that progenitor cells were mobile and that these progenitor cells could move through the body and migrate towards the tissue where they are needed. Many properties are shared by adult stem cells and progenitor cells.
Research
Progenitor cells have become a hub for research on a few different fronts. Current research on progenitor cells focuses on two different applications: regenerative medicine and cancer biology. Research on regenerative medicine has focused on progenitor cells, and stem cells, because their cellular senescence contributes largely to the process of aging. Research on cancer biology focuses on the impact of progenitor cells on cancer responses, and the way that these cells tie into the immune response.
The natural aging of cells, called their cellular senescence, is one of the main contributors to aging on an organismal level. There are a few different ideas to the cause behind why aging happens on a cellular level. Telomere length has been shown to positive
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https://en.wikipedia.org/wiki/Pathfinder%20network
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A method for pruning dense networks to highlight key links
Rationale
Relationships among a set of elements are often represented as a square matrix with entries representing the relations between all pairs of the elements. Relations such as distances, dissimilarities, similarities, relatedness, correlations, co-occurrences, conditional probabilities, etc., can be represented by such matrices. Such data can also be represented as networks with weighted links between the elements. Such matrices and networks are extremely dense and are not easily apprehended without some form of data reduction or pruning.
A pathfinder network results from applying a pruning method that removes weaker links from a (usually dense) network according to the lengths of alternative paths (see below). It is used as a psychometric scaling method based on graph theory and used in the study of expertise, education, knowledge acquisition, mental models, and knowledge engineering. It is also employed in generating communication networks, software debugging, visualizing scientific citation patterns, information retrieval, and other forms of data visualization. Pathfinder networks are potentially applicable to any problem addressed by network theory.
Overview
Network pruning aims to highlight the more important links between elements represented in a network. It helps to simplify the collection of connections involved which is valuable in data visualization and in comprehending essential relations among the elements represented in the network.
Several psychometric scaling methods start from pairwise data and yield structures revealing the underlying organization of the data. Data clustering and multidimensional scaling are two such methods. Network scaling represents another method based on graph theory. Pathfinder networks are derived from matrices of data for pairs of entities. Because the algorithm uses distances, similarity data are inverted to yield dissimilarities for the computat
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https://en.wikipedia.org/wiki/Pipe%20organ%20tuning
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This article describes the process and techniques involved in the tuning of a pipe organ. Electronic organs typically do not require tuning.
A pipe organ produces sound via hundreds or thousands of organ pipes, each of which produces a single pitch and timbre. The goal of tuning a pipe organ is to adjust the pitch of each pipe so that they all sound in tune with each other.
Pitch
For many years, there was no pitch standard across Europe. The frequency of (the standard note for tuning musical instruments), for example, could range from =392 Hz in parts of France to =465 Hz (Cornet-ton pitch) in parts of Germany. Organs were often tuned differently than ensembles, even within the same region or town. The modern tuning standard of =440 Hz (=262 Hz) was proposed in 1939, and accepted by the International Organization for Standardization (as ISO 16) in 1955 and again in 1975.
Process
The first task of an organ tuner is to select a temperament. Generally speaking, the temperament of a pipe organ is part of its design, and is not lightly changed during its lifetime. Equal temperament is very common, but by no means universal. Along with the temperament goes the overall concert pitch of the instrument, often A=440 Hz in modern instruments, but this also is far from universal. The pitch of an organ cannot be significantly changed without major work, as pipes need to be shortened or lengthened.
Another important preparation step is to stabilize the temperature of the building in which the organ resides. Ideally, the temperature should be the same as that at which the organ will be typically used, and the temperature should have been stable for many hours before beginning the tuning. The reason for this is that the pitch of organ pipes vary significantly with temperature, and not all pipes vary at the same rate relative to temperature.
The actual tuning process begins with the tuning of the "tuning stop", the stop to which most or all other stops will be tuned
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https://en.wikipedia.org/wiki/Lymphology%20Association%20of%20North%20America
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The Lymphology Association of North America, formerly known as the American Society of Lymphology, is a non-profit organization based in Kansas City, Missouri. The society provides current information and resources for professionals and patients interested in the healthy function and disorders of the lymphatic system, such as immune response, allergies, infectious disease and circulatory disorders lymphedema, relation to other systems of the body (integument, cardiac, venous, etc.), anatomical structures and functions, cancers, and integrative therapies. It organizes resources, conferences, and produces various publications.
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https://en.wikipedia.org/wiki/Lax%20pair
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In mathematics, in the theory of integrable systems, a Lax pair is a pair of time-dependent matrices or operators that satisfy a corresponding differential equation, called the Lax equation. Lax pairs were introduced by Peter Lax to discuss solitons in continuous media. The inverse scattering transform makes use of the Lax equations to solve such systems.
Definition
A Lax pair is a pair of matrices or operators dependent on time and acting on a fixed Hilbert space, and satisfying Lax's equation:
where is the commutator.
Often, as in the example below, depends on in a prescribed way, so this is a nonlinear equation for as a function of .
Isospectral property
It can then be shown that the eigenvalues and more generally the spectrum of L are independent of t. The matrices/operators L are said to be isospectral as varies.
The core observation is that the matrices are all similar by virtue of
where is the solution of the Cauchy problem
where I denotes the identity matrix. Note that if P(t) is skew-adjoint, U(t,s) will be unitary.
In other words, to solve the eigenvalue problem Lψ = λψ at time t, it is possible to solve the same problem at time 0 where L is generally known better, and to propagate the solution with the following formulas:
(no change in spectrum)
Through principal invariants
The result can also be shown using the invariants for any . These satisfy
due to the Lax equation, and since the characteristic polynomial can be written in terms of these traces, the spectrum is preserved by the flow.
Link with the inverse scattering method
The above property is the basis for the inverse scattering method. In this method, L and P act on a functional space (thus ψ = ψ(t,x)), and depend on an unknown function u(t,x) which is to be determined. It is generally assumed that u(0,x) is known, and that P does not depend on u in the scattering region where .
The method then takes the following form:
Compute the spectrum of , giving and ,
In the sc
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https://en.wikipedia.org/wiki/Kenji%20Urada
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Kenji Urada (c. 1944 – July 4, 1981) was a Japanese factory worker who was killed by a robot. Urada is often incorrectly reported to be the first person killed by a robot, but Robert Williams, a worker at the Ford Motor Company's Michigan Casting Center, had been killed by a robot over two years earlier, on January 25, 1979.
Urada was a maintenance worker at the Kawasaki Heavy Industries plant in Akashi. He died while checking a malfunctioning robot; after jumping over a safety barrier, which was designed to shut down power to the machine when open, he apparently started the robot inadvertently. The robot, built by Kawasaki under a license from Unimation, pinned him against an adjacent machine and either crushed him or stabbed him in the back. Other workers in the factory were unable to stop the machine as they were unfamiliar with its operation.
International newswire service UPI reported Urada was the first human killed by a robot on December 8, 1981. The circumstances of his death were not made public until after an investigation by the Hyōgo labor standards bureau was completed. The investigation concluded that workers were not sufficiently familiar with the machines and the machines were not sufficiently regulated. The robot that killed Urada was removed from the Akashi plant, and man-high fences were erected around the other two robots in the plant in the wake of the accident.
See also
List of unusual deaths
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https://en.wikipedia.org/wiki/Zeek
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Zeek is a free and open-source software network analysis framework. Vern Paxson began development work on Zeek in 1995 at Lawrence Berkeley National Lab. Zeek is a network security monitor (NSM) but can also be used as a network intrusion detection system (NIDS). The Zeek project releases the software under the BSD license.
Output
Zeek's purpose is to inspect network traffic and generate a variety of logs describing the activity it sees. A complete list of log files is available at the project documentation site.
Log example
The following is an example of one entry in JSON format from the conn.log:
Threat hunting
One of Zeek's primary use cases involves cyber threat hunting.
Name
It principal author, Paxson, originally named the software "Bro" as a warning regarding George Orwell's Big Brother from the novel Nineteen Eighty-Four. In 2018 the project leadership team decided to rename the software. At LBNL in the 1990s, the developers ran their sensors as a pseudo-user named "zeek", thereby inspiring the name change in 2018.
Zeek deployment
Security teams identify locations on their network where they desire visibility. They deploy one or more network taps or enable switch SPAN ports for port mirroring to gain access to traffic. They deploy Zeek on servers with access to those visibility points. The Zeek software on the server deciphers network traffic as logs, writing them to local disk or remote storage.
Zeek application architecture and analyzers
Zeek's event engine analyzes live or recorded network traffic to generate neutral event logs. Zeek uses common ports and dynamic protocol detection (involving signatures as well as behavioral analysis) to identify network protocols.
Developers write Zeek policy scripts in the Turing complete Zeek scripting language. By default Zeek logs information about events to files, but analysts can also configure Zeek to take other actions, such as sending an email, raising an alert, executing a system command, updating an
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https://en.wikipedia.org/wiki/Stress%E2%80%93energy%E2%80%93momentum%20pseudotensor
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In the theory of general relativity, a stress–energy–momentum pseudotensor, such as the Landau–Lifshitz pseudotensor, is an extension of the non-gravitational stress–energy tensor that incorporates the energy–momentum of gravity. It allows the energy–momentum of a system of gravitating matter to be defined. In particular it allows the total of matter plus the gravitating energy–momentum to form a conserved current within the framework of general relativity, so that the total energy–momentum crossing the hypersurface (3-dimensional boundary) of any compact space–time hypervolume (4-dimensional submanifold) vanishes.
Some people (such as Erwin Schrödinger) have objected to this derivation on the grounds that pseudotensors are inappropriate objects in general relativity, but the conservation law only requires the use of the 4-divergence of a pseudotensor which is, in this case, a tensor (which also vanishes). Also, most pseudotensors are sections of jet bundles, which are now recognized as perfectly valid objects in general relativity.
Landau–Lifshitz pseudotensor
The Landau–Lifshitz pseudotensor, a stress–energy–momentum pseudotensor for gravity, when combined with terms for matter (including photons and neutrinos), allows the energy–momentum conservation laws to be extended into general relativity.
Requirements
Landau and Lifshitz were led by four requirements in their search for a gravitational energy momentum pseudotensor, :
that it be constructed entirely from the metric tensor, so as to be purely geometrical or gravitational in origin.
that it be index symmetric, i.e. , (to conserve angular momentum)
that, when added to the stress–energy tensor of matter, , its total 4-divergence vanishes (this is required of any conserved current) so that we have a conserved expression for the total stress–energy–momentum.
that it vanish locally in an inertial frame of reference (which requires that it only contains first order and not second or higher order derivatives o
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https://en.wikipedia.org/wiki/Sex%20allocation
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Sex allocation is the allocation of resources to male versus female reproduction in sexual species. Sex allocation theory tries to explain why many species produce equal number of males and females.
In dioecious species, where individuals are either male or female for their entire lifetimes, the allocation decision lies between producing male or female offspring. In sequential hermaphrodites, where individuals function as one sex early in life and then switch to the other, the allocation decisions lie in what sex to be first and when to change sex. Animals may be dioecious or sequential hermaphrodites. Sex allocation theory also applies to flowering plants, which can be dioecious, simultaneous hermaphrodites, have unisexual plants and hermaphroditic plants in the same population, have unisexual flowers and hermaphroditic flowers on the same plant or to have only hermaphroditic flowers.
Fisher’s principle and equal sex allocation
R.A. Fisher developed an explanation, known as Fisher's principle, of why sex ratios in many animals are 1:1. If there were 10 times more females in a population than males, a male would on average be able to mate with more partners than a female would. Parents who preferentially invested in producing male offspring would have a fitness advantage over those who preferentially produced females. This strategy would result in increasing numbers of males in the population, thus eliminating the original advantage of males. The same would occur if there were originally more males than females in a population. The evolutionarily stable strategy (ESS) in this case would be for parents to produce a 1:1 ratio of males and females.
This explanation assumed that males and females are equally costly for parents to produce. However, if one sex were more costly than the other, parents would allot their resources to their offspring differentially. If parents could have two daughters for the same cost as one male because males took twice the energy to re
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https://en.wikipedia.org/wiki/Fundamental%20thermodynamic%20relation
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In thermodynamics, the fundamental thermodynamic relation are four fundamental equations which demonstrate how four important thermodynamic quantities depend on variables that can be controlled and measured experimentally. Thus, they are essentially equations of state, and using the fundamental equations, experimental data can be used to determine sought-after quantities like G (Gibbs free energy) or H (enthalpy). The relation is generally expressed as a microscopic change in internal energy in terms of microscopic changes in entropy, and volume for a closed system in thermal equilibrium in the following way.
Here, U is internal energy, T is absolute temperature, S is entropy, P is pressure, and V is volume.
This is only one expression of the fundamental thermodynamic relation. It may be expressed in other ways, using different variables (e.g. using thermodynamic potentials). For example, the fundamental relation may be expressed in terms of the enthalpy H as
in terms of the Helmholtz free energy F as
and in terms of the Gibbs free energy G as
.
The first and second laws of thermodynamics
The first law of thermodynamics states that:
where and are infinitesimal amounts of heat supplied to the system by its surroundings and work done by the system on its surroundings, respectively.
According to the second law of thermodynamics we have for a reversible process:
Hence:
By substituting this into the first law, we have:
Letting be reversible pressure-volume work done by the system on its surroundings,
we have:
This equation has been derived in the case of reversible changes. However, since U, S, and V are thermodynamic state functions that depends on only the initial and final states of a thermodynamic process, the above relation holds also for non-reversible changes. If the composition, i.e. the amounts of the chemical components, in a system of uniform temperature and pressure can also change, e.g. due to a chemical reaction, the fundamental thermodynam
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https://en.wikipedia.org/wiki/Least-concern%20species
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A least-concern species is a species that has been categorized by the International Union for Conservation of Nature (IUCN) as evaluated as not being a focus of species conservation because the specific species is still plentiful in the wild. They do not qualify as threatened, near threatened, or (before 2001) conservation dependent.
Species cannot be assigned the "Least Concern" category unless they have had their population status evaluated. That is, adequate information is needed to make a direct, or indirect, assessment of its risk of extinction based on its distribution or population status.
Evaluation
Since 2001 the category has had the abbreviation "LC", following the IUCN 2001 Categories & Criteria (version 3.1). Before 2001 "least concern" was a subcategory of the "Lower Risk" category and assigned the code "LR/lc" or lc. Around 20% of least concern taxa (3261 of 15,636) in the IUCN database still use the code "LR/lc", which indicates they have not been re-evaluated since 2000.
Number of species
While "least concern" is not considered a red listed category by the IUCN, the 2006 IUCN Red List still assigns the category to 15,636 taxa. The number of animal species listed in this category totals 14,033 (which includes several undescribed species such as a frog from the genus Philautus). There are also 101 animal subspecies listed and 1500 plant taxa (1410 species, 55 subspecies, and 35 varieties). No fungi or protista have the classification, though only four species in those kingdoms have been evaluated by the IUCN. Humans were formally assessed as a species of least concern in 2008.
List of LC species
See also
Conservation status
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https://en.wikipedia.org/wiki/Oncofetal%20antigen
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Oncofetal antigens are proteins which are typically present only during fetal development but are found in adults with certain kinds of cancer. These proteins are often measurable in the blood of individuals with cancer and may be used to both diagnose and follow treatment of the tumors. One example of an oncofetal antigen is alpha-fetoprotein, which is produced by hepatocellular carcinoma and some germ cell tumors. Another example is carcinoembryonic antigen, which is elevated in people with colon cancer and other tumors. Other oncofetal antigens are trophoblast glycoprotein precursor and immature laminin receptor protein (also known as oncofetal antigen protein). Oncofetal antigens are promising targets for vaccination against several types of cancers.
External links
Entrez protein entry for trophoblast glycoprotein precursor
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https://en.wikipedia.org/wiki/TechnoSphere%20%28virtual%20environment%29
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TechnoSphere was an online digital environment launched on September 1, 1995 and hosted on a computer at a UK university. Created by Jane Prophet and Dr. Gordon Selley, TechnoSphere was a place where users from around the globe could create creatures and release them into the 3D environment, described by the creators as a "digital ecology." Earlier incarnations of TechnoSphere did not have the advantage of web-accessible 3D graphics, but was still governed by chaos theory and similar algorithms that determined each creature's unique behavior based on their components and interactions with each other and their environment.
The online program was one of many digital artificial life simulations that evolved as the World Wide Web began to grow. Many museums and classrooms found the tool to be a valuable complement to learning material on natural selection and ecosystems. The experiment operated online until 2002. It was relaunched on January 15, 2007, but became offline again as of November 2012.
Description
TechnoSphere was a real-time, 3D simulation of an environment that was populated by virtual creatures. Users across the globe had the capability to create their own creatures through a website. TechnoSphere III, one of many incarnations of the original design, used an artificial life program and fractal landscapes, which were governed by a complex set of rules and algorithms that determined how the virtual ecosystem reacted. The program was capable of modeling such concepts as simple evolution and carrying capacity. Despite limited available creature designs, no two would ever behave in the same way, due to chance interactions with its environment and other creatures.
Physically, the virtual landscape of TechnoSphere consisted of 16 km2 of terrain. It was capable of supporting approximately 4,000 creatures, though other sources suggest that as many as 20,000 creatures typically would coexist in the virtual environment at one time. After the relaunch, it was expl
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https://en.wikipedia.org/wiki/Thermal%20transmittance
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Thermal transmittance is the rate of transfer of heat through matter. The thermal transmittance of a material (such as insulation or concrete) or an assembly (such as a wall or window) is expressed as a U-value. The thermal insulance of a structure is the reciprocal of its thermal transmittance.
U-value
Although the concept of U-value (or U-factor) is universal, U-values can be expressed in different units. In most countries, U-value is expressed in SI units, as watts per square metre-kelvin:
W/(m2⋅K)
In the United States, U-value is expressed as British thermal units (Btu) per hour-square feet-degrees Fahrenheit:
Btu/(h⋅ft2⋅°F)
Within this article, U-values are expressed in SI unless otherwise noted. To convert from SI to US customary values, divide by 5.678.
Well-insulated parts of a building have a low thermal transmittance whereas poorly insulated parts of a building have a high thermal transmittance. Losses due to thermal radiation, thermal convection and thermal conduction are taken into account in the U-value. Although it has the same units as heat transfer coefficient, thermal transmittance is different in that the heat transfer coefficient is used to solely describe heat transfer in fluids while thermal transmittance is used to simplify an equation that has several different forms of thermal resistances.
It is described by the equation:
Φ = A × U × (T1 - T2)
where Φ is the heat transfer in watts, U is the thermal transmittance, T1 is the temperature on one side of the structure, T2 is the temperature on the other side of the structure and A is the area in square metres.
Thermal transmittances of most walls and roofs can be calculated using ISO 6946, unless there is metal bridging the insulation in which case it can be calculated using ISO 10211. For most ground floors it can be calculated using ISO 13370. For most windows the thermal transmittance can be calculated using ISO 10077 or ISO 15099. ISO 9869 describes how to measure the thermal transmi
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https://en.wikipedia.org/wiki/Siemens%20Communications
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Siemens Communications was the communications and information business arm of German industrial conglomerate Siemens AG, until 2006. It was the largest division of Siemens, and had two business units – Mobile Networks and Fixed Networks; and Enterprise.
Siemens Communications division was founded in 1998 through the amalgamation of a number of early groups / divisions of Siemens AG, the oldest of which traces back to the company 'Siemens & Halske Telegraph Construction Company' founded in 1847, and the most prominent predecessor being the 1978-founded 'Siemens Communication Systems'. On October 1, 2006, Siemens AG decided to divide Siemens Communications into two companies: 'Siemens Networks GmbH & Co. KG' and 'Siemens Enterprise Communications GmbH & Co. KG'.
The company remains extant, through a series of mergers and divisions, as Siemens Enterprise Communications – a 2008 joint venture with the Gores Group where Siemens AG hold 49% with the balance of 51% held by the American partner.
History
Origins (1847–1978)
Siemens Communications traces its origins to the company Siemens & Halske Telegraph Construction Company (German legal name: Telegraphen-Bauanstalt von Siemens & Halske) founded by Werner von Siemens on 12 October 1847. Based on the telegraph, his invention used a needle to point to the sequence of letters, instead of using Morse code.
In 1848, the company built the first long-distance telegraph line in Europe – 500 km from Berlin to Frankfurt am Main – and by the early 1850s the company was involved in building long distance telegraph networks in Russia. In 1867, Siemens completed the monumental Indo-European telegraph line stretching over 11,000 km from London to Calcutta. In 1897, Siemens & Halske went public.
During the first half of the 20th century, there were a series of mergers and divisions, which led to formation of three separate companies. First was the original company, Siemens & Halske, which focused on communications engineering; the
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https://en.wikipedia.org/wiki/Limes%20Saxoniae
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The (Latin for "Limit of Saxony"), also known as the Limes Saxonicus or Sachsenwall ("Saxon Dyke"), was an unfortified limes or border between the Saxons and the Slavic Obotrites, established about 810 in present-day Schleswig-Holstein.
After Charlemagne had removed Saxons from some of their lands and given it to the Obotrites (who were allies of Charlemagne), he finally managed to conquer the Saxons in the Saxon Wars. In 811 he signed the Treaty of Heiligen with the neighbouring Danes and may at the same time have reached a border agreement with the Polabian Slavs in the east. This border should not be thought of as a fortified line, however, but rather a defined line running through the middle of the border zone, an area of bog and thick forest that was difficult to pass through. According to Adam of Bremen's description in the Gesta Hammaburgensis ecclesiae pontificum about 1075, it ran from the Elbe river near Boizenburg northwards along the Bille river to the mouth of the Schwentine at the Kiel Fjord and the Baltic Sea.
It was breached several times by the Slavic Obotrites (983 and 1086) and Mieszko II Lambert of Poland (1028 and 1030). The Limes was dissolved during the first phase of the Ostsiedlung, when Count Henry of Badewide campaigned in Wagrian lands in 1138/39 and the Slavic population was Germanized by German, mostly Saxon, settlers.
Bibliography
Matthias Hardt: "Hesse, Elbe, Saale and the Frontiers of the Carolingian Empire." In: Walther Pool / Ian N. Wood / Helmut Reimitz (Hrsg.): The Transformation of Frontiers from Late Antiquity to the Carolingians. The Transformation of the Roman World 10. Leiden-Boston-Köln 2001, S. 219–232, .
Matthias Hardt: "Limes Saxoniae." In: Reallexikon der Germanischen Altertumskunde, Bd. 18, Landschaftsrecht – Loxstedt. Berlin-New York 2001, S. 442–446, .
Günther Bock: "Böhmische Dörfer“ in Stormarn? – Verlauf und Bedeutung des Limes Saxoniae zwischen Bille und Trave." In: Derselbe: Studien zur Geschichte Stormarn
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https://en.wikipedia.org/wiki/Flavodoxin
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Flavodoxins (Fld) are small, soluble electron-transfer proteins. Flavodoxins contains flavin mononucleotide as prosthetic group. The structure of flavodoxin is characterized by a five-stranded parallel beta sheet, surrounded by five alpha helices. They have been isolated from prokaryotes, cyanobacteria, and some eukaryotic algae.
Background
Originally found in cyanobacteria and clostridia, flavodoxins were discovered over 50 years ago. These proteins evolved from an anaerobic environment, due to selective pressures. Ferredoxin, another redox protein, was the only protein able to be used in this manner. However, when oxygen became present in the environment, iron became limited. Ferredoxin is iron-dependant as well as oxidant-sensitive. Under these limited iron conditions, ferredoxin was no longer preferred. Flavodoxin on the other hand is the opposite of these traits, as it is oxidant-resistant and has iron-free isofunctional counterparts. Therefore, for some time flavodoxin was the primary redox protein. Now however, when ferredoxin and flavodoxin are present in the same genome, ferredoxin is still used but under low iron conditions, flavodoxin is induced.
Structure
Three forms of flavodoxin exist: Oxidized, (OX) semiquinone, (SQ) and hydroquinone (HQ). While relatively small (Mw = 15-22 kDa), flavodoxins exist in "long" and "short" chain classifications. Short chain flavodoxins contain between 140 and 180 amino acid residues, while long chain flavodoxins include a 20 amino acid insertion into the last beta-strand. These residues form a loop which may be used to increase the binding affinity of flavin mononucleotide as well as assist in the formation of folded intermediates. However, it is still not certain what the loops true function is. In addition, the flavin mononucleotide is non-covalently bound to the flavodoxin protein and works to shuttle electrons.
Medical applications
Heliobacter pylori (Hp), the most prevalent human gastric pathogen, requires fla
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https://en.wikipedia.org/wiki/Interactive%20design
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Interactive design is a user-oriented field of study that focuses on meaningful communication using media to create products through cyclical and collaborative processes between people and technology. Successful interactive designs have simple, clearly defined goals, a strong purpose and intuitive screen interface.
Interactive design compared to interaction design
In some cases interactive design is equated to interaction design; however, in the specialized study of interactive design there are defined differences.
To assist in this distinction, interaction design can be thought of as:
Making devices usable, useful, and fun, focusing on the efficiency and intuitive hardware
A fusion of product design, computer science, and communication design
A process of solving specific problems under a specific set of contextual circumstances
The creation of form for the behavior of products, services, environments, and systems
Making dialogue between technology and user invisible, i.e. reducing the limitations of communication through and with technology.
About connecting people through various products and services,
Whereas interactive design can be thought of as:
Giving purpose to interaction design through meaningful experiences
Consisting of six main components including User control, Responsiveness, Real-Time Interactions, Connectedness, Personalization, and Playfulness
Focuses on the use and experience of the software
Retrieving and processing information through on-demand responsiveness
Acting upon information to transform it
The constant changing of information and media, regardless of changes in the device
Providing interactivity through a focus on the capabilities and constraints of human cognitive processing
While both definitions indicate a strong focus on the user, the difference arises from the purposes of interactive design and interaction design. In essence interactive design involves the creation of interactive products and services, whi
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https://en.wikipedia.org/wiki/Fatty%20acid%20transport%20proteins
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Fatty acid transport proteins (FATPs, SLC27, SLC27A) are a family of trans-membrane transport proteins, which allow and enhance the uptake of long chain fatty acids into cells. This subfamily is part of the solute carrier protein family. Within humans this family contains six very homologous proteins, which are expressed in all tissues of the body which use fatty acids:
SLC27A1 (FATP1) Long-chain fatty acid transport protein 1
SLC27A2 (FATP2) Very long-chain acyl-CoA synthetase
SLC27A3 (FATP3) Solute carrier family 27 member 3
SLC27A4 (FATP4) Long-chain fatty acid transport protein 4
SLC27A5 (FATP5) Bile acyl-CoA synthetase
SLC27A6 (FATP6) Long-chain fatty acid transport protein 6
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https://en.wikipedia.org/wiki/Ideal%20triangle
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In hyperbolic geometry an ideal triangle is a hyperbolic triangle whose three vertices all are ideal points. Ideal triangles are also sometimes called triply asymptotic triangles or trebly asymptotic triangles. The vertices are sometimes called ideal vertices. All ideal triangles are congruent.
Properties
Ideal triangles have the following properties:
All ideal triangles are congruent to each other.
The interior angles of an ideal triangle are all zero.
An ideal triangle has infinite perimeter.
An ideal triangle is the largest possible triangle in hyperbolic geometry.
In the standard hyperbolic plane (a surface where the constant Gaussian curvature is −1) we also have the following properties:
Any ideal triangle has area π.
Distances in an ideal triangle
The inscribed circle to an ideal triangle has radius
.
The distance from any point in the triangle to the closest side of the triangle is less than or equal to the radius r above, with equality only for the center of the inscribed circle.
The inscribed circle meets the triangle in three points of tangency, forming an equilateral contact triangle with side length where is the golden ratio.
A circle with radius d around a point inside the triangle will meet or intersect at least two sides of the triangle.
The distance from any point on a side of the triangle to another side of the triangle is equal or less than , with equality only for the points of tangency described above.
a is also the altitude of the Schweikart triangle.
If the curvature is −K everywhere rather than −1, the areas above should be multiplied by 1/K and the lengths and distances should be multiplied by 1/.
Thin triangle condition
Because the ideal triangle is the largest possible triangle in hyperbolic geometry, the measures above are maxima possible for any hyperbolic triangle, this fact is important in the study of δ-hyperbolic space.
Models
In the Poincaré disk model of the hyperbolic plane, an ideal triangle
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https://en.wikipedia.org/wiki/Neurophysins
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Neurophysins are carrier proteins which transport the hormones oxytocin and vasopressin to the posterior pituitary from the paraventricular and supraoptic nucleus of the hypothalamus, respectively. Inside the neurosecretory granules, the analogous neurophysin I and II form stabilizing complexes via covalent interactions. Stabilizing neurophysin-hormone complexes that are formed within neurosecretory granules located in the posterior pituitary gland aid in intra-axonal transport. During intra-axonal transport, the neurophysin's are believed to prevent the bound hormone from leaking into the cytoplasmic space and proteolytic digestion via enzymes. However, due to the low concentration of neurophysin in the blood, it is likely the protein-hormone complex dissociates, indicating the neurophysin does not aid in transporting the hormone through the circulatory system.
Neurophysins are also secreted out of the posterior pituitary hypothalamus, each carrying their respective associated passenger hormone. When the posterior pituitary hypothalamus secretes vasopressin and its neurophysin carrier, it also secretes a glycopeptide.
There are two types:
Neurophysin I - Oxytocin
Neurophysin II - Vasopressin (Also known as "antidiuretic hormone" or ADH)
Biosynthesis of Neurophysins
These proteins are synthesized in the cell bodies of the supraoptic and paraventricular regions of the hypothalamus.
The disulfide-rich neurophysin protein is suggested to be congruent with the synthesis of insulin in which a precursor molecule of higher molecular weight is proteolytically cleaved and forms disulfide linkages.
Although not enough data has been obtained, it is hypothesized that there is a common precursor molecule between neurophysin and the two hormones it stabilizes.
Structure
Neurophysins are acidic proteins with a molecular weight of approximately 10,000 Da that are rich in cysteine, glycine, and proline residues . The protein is double domain with a polypeptide chain of 9
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https://en.wikipedia.org/wiki/AEGIS%20SecureConnect
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AEGIS SecureConnect (or simply AEGIS) is the former name of a network authentication system used in IEEE 802.1X networks. It was developed by Meetinghouse Data Communications, Inc.; the system was renamed "Cisco Secure Services Client" when Meetinghouse was acquired by Cisco Systems. The AEGIS Protocol is an 802.1X supplicant (i.e. handles authentication for wired and wireless networks, such as those that use WPA-PSK, WPA-Radius, or Certificate-based authentication), and is commonly installed along with a Network Interface Card's (NIC) or VPN drivers.
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https://en.wikipedia.org/wiki/Directional%20stability
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Directional stability is stability of a moving body or vehicle about an axis which is perpendicular to its direction of motion. Stability of a vehicle concerns itself with the tendency of a vehicle to return to its original direction in relation to the oncoming medium (water, air, road surface, etc.) when disturbed (rotated) away from that original direction. If a vehicle is directionally stable, a restoring moment is produced which is in a direction opposite to the rotational disturbance. This "pushes" the vehicle (in rotation) so as to return it to the original orientation, thus tending to keep the vehicle oriented in the original direction.
Directional stability is frequently called "weather vaning" because a directionally stable vehicle free to rotate about its center of mass is similar to a weather vane rotating about its (vertical) pivot.
With the exception of spacecraft, vehicles generally have a recognisable front and rear and are designed so that the front points more or less in the direction of motion. Without this stability, they may tumble end over end, spin or orient themselves at a high angle of attack, even broadside on to the direction of motion. At high angles of attack, drag forces may become excessive, the vehicle may be impossible to control, or may even experience structural failure. In general, land, sea, air and underwater vehicles are designed to have a natural tendency to point in the direction of motion.
Example: road vehicle
Arrows, darts, rockets, and airships have tail surfaces (fins or feathers) to achieve directional stability; an airplane uses its vertical stabilizer for the same purpose. A road vehicle does not have elements specifically designed to maintain stability, but relies primarily on the distribution of mass.
Introduction
These points are best illustrated with an example. The first stage of studying the stability of a road vehicle is the derivation of a reasonable approximation to the equations of motion.
The diag
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https://en.wikipedia.org/wiki/CCAAT-enhancer-binding%20proteins
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CCAAT-enhancer-binding proteins (or C/EBPs) is a family of transcription factors composed of six members, named from C/EBPα to C/EBPζ. They promote the expression of certain genes through interaction with their promoters. Once bound to DNA, C/EBPs can recruit so-called co-activators (such as CBP) that in turn can open up chromatin structure or recruit basal transcription factors.
Function
C/EBP proteins interact with the CCAAT (cytosine-cytosine-adenosine-adenosine-thymidine) box motif, which is present in several gene promoters. They are characterized by a highly conserved basic-leucine zipper (bZIP) domain at the C-terminus. This domain is involved in dimerization and DNA binding, as are other transcription factors of the leucine zipper domain-containing family (c-Fos and c-jun). The bZIP domain structure of C/EBPs is composed of an α-helix that forms a "coiled coil" structure when it dimerizes. Members of the C/EBP family can form homodimers or heterodimers with other C/EBPs and with other transcription factors, which may or may not contain the leucine zipper domain. The dimerization is necessary to enable C/EBPs to bind specifically to DNA through a palindromic sequence in the major groove of the DNA. C/EBP proteins also contain activation domains at the N-terminus and regulatory domains.
These proteins are found in hepatocytes, adipocytes, hematopoietic cells, spleen, kidney, brain, and many other organs. C/EBP proteins are involved in different cellular responses, such as in the control of cellular proliferation, growth and differentiation, in metabolism, and in immunity. Nearly all the members of the C/EBP family can induce transcription through their activation domains by interacting with components of the basal transcription apparatus. (C/EBPγ is an exception that lacks a functional transcriptional activation domain.) Their expression is regulated at multiple levels, including through hormones, mitogens, cytokines, nutrients, and other factors.
This p
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https://en.wikipedia.org/wiki/Landscape%20connectivity
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In landscape ecology, landscape connectivity is, broadly, "the degree to which the landscape facilitates or impedes movement among resource patches". Alternatively, connectivity may be a continuous property of the landscape and independent of patches and paths. Connectivity includes both structural connectivity (the physical arrangements of disturbance and/or patches) and functional connectivity (the movement of individuals across contours of disturbance and/or among patches). Functional connectivity includes actual connectivity (requires observations of individual movements) and potential connectivity in which movement paths are estimated using the life-history data.
A similar but different concept proposed by Jacques Baudry, landscape connectedness, refers to structural links between elements of spatial structures of a landscape, which concerns the topology of landscape features and not ecological processes.
Definition
The concept of "landscape connectivity" was first introduced by Dr. Gray Merriam in 1984. Merriam noted that movement among habitat patches was not merely a function of an organism's attributes, but also, a quality of the landscape elements through which it must move. To emphasize this fundamental interaction in determining a particular movement pathway, Merriam (1984), defined landscape connectivity as "the degree to which absolute isolation is prevented by landscape elements which allow organisms to move among habitat patches." Nine years later, Merriam and colleagues, revised the definition to "the degree to which the landscape impedes or facilitates movement among resource patches. Although this definition has undoubtedly become the most accepted and cited meaning within the scientific literature, many authors have continued to create their own definitions. With et al (1997), presented their interpretation as "the functional relationship among habitat patches, owing to the spatial contagion of habitat and the movement responses of organisms t
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https://en.wikipedia.org/wiki/Interferon%20regulatory%20factors
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Interferon regulatory factors (IRF) are proteins which regulate transcription of interferons (see regulation of gene expression). Interferon regulatory factors contain a conserved N-terminal region of about 120 amino acids, which folds into a structure that binds specifically to the IRF-element (IRF-E) motifs, which is located upstream of the interferon genes. Some viruses have evolved defense mechanisms that regulate and interfere with IRF functions to escape the host immune system. For instance, the remaining parts of the interferon regulatory factor sequence vary depending on the precise function of the protein. The Kaposi sarcoma herpesvirus, KSHV, is a cancer virus that encodes four different IRF-like genes; including vIRF1, which is a transforming oncoprotein that inhibits type 1 interferon activity. In addition, the expression of IRF genes is under epigenetic regulation by promoter DNA methylation.
Role in IFN signaling
IRFs primarily regulate type I IFNs in the host after pathogen invasion and are considered the crucial mediators of an antiviral response. Following a viral infection, pathogens are detected by Pattern Recognition Receptors (PRRs), including various types of Toll-like Receptors (TLR) and cytosolic PRRs, in the host cell. The downstream signaling pathways from PRR activation phosphorylate ubiquitously expressed IRFs (IRF1, IRF3, and IRF7) through IRF kinases, such as TANK-binding kinase 1 (TBK1). Phosphorylated IRFs are translocated to the nucleus where they bind to IRF-E motifs and activate the transcription of Type I IFNs. In addition to IFNs, IRF1 and IRF5 has been found to induce transcription of pro-inflammatory cytokines.
Some IFNs like IRF2 and IRF4 regulate the activation of IFNs and pro-inflammatory cytokines through inhibition. IRF2 contains a repressor region that downregulates expression of type I IFNs. IRF4 competes with IRF5, and inhibits its sustained activity.
Role in immune cell development
In addition to the signal transd
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https://en.wikipedia.org/wiki/E-selectin
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E-selectin, also known as CD62 antigen-like family member E (CD62E), endothelial-leukocyte adhesion molecule 1 (ELAM-1), or leukocyte-endothelial cell adhesion molecule 2 (LECAM2), is a selectin cell adhesion molecule expressed only on endothelial cells activated by cytokines. Like other selectins, it plays an important part in inflammation. In humans, E-selectin is encoded by the SELE gene.
Structure
E selectin has a cassette structure: an N-terminal, C-type lectin domain, an EGF (epidermal-growth-factor)-like domain, 6 Sushi domain (SCR repeat) units, a transmembrane domain (TM) and an intracellular cytoplasmic tail (cyto). The three-dimensional structure of the ligand-binding region of human E-selectin has been determined at 2.0 Å resolution in 1994. The structure reveals limited contact between the two domains and a coordination of Ca2+ not predicted from other C-type lectins. Structure/function analysis indicates a defined region and specific amino-acid side chains that may be involved in ligand binding. The E-selectin bound to sialyl-LewisX (SLeX; NeuNAcα2,3Galβ1,4[Fucα1,3]GlcNAc) tetrasaccharide was solved in 2000.
Gene and regulation
In humans, E-selectin is encoded by the SELE gene. Its C-type lectin domain, EGF-like, SCR repeats, and transmembrane domains are each encoded by separate exons, whereas the E-selectin cytosolic domain derives from two exons. The E-selectin locus flanks the L-selectin locus on chromosome 1.
Different from P-selectin, which is stored in vesicles called Weibel-Palade bodies, E-selectin is not stored in the cell and has to be transcribed, translated, and transported to the cell surface. The production of E-selectin is stimulated by the expression of P-selectin which in turn, is stimulated by tumor necrosis factor α (TNFα), interleukin-1 (IL-1) and lipopolysaccharide (LPS). It takes about two hours, after cytokine recognition, for E-selectin to be expressed on the endothelial cell's surface. Maximal expression of E-selectin
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https://en.wikipedia.org/wiki/Membranous%20labyrinth
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The membranous labyrinth is a collection of fluid filled tubes and chambers which contain the receptors for the senses of equilibrium and hearing. It is lodged within the bony labyrinth in the inner ear and has the same general form; it is, however, considerably smaller and is partly separated from the bony walls by a quantity of fluid, the perilymph.
In certain places, it is fixed to the walls of the cavity.
The membranous labyrinth contains fluid called endolymph. The walls of the membranous labyrinth are lined with distributions of the cochlear nerve, one of the two branches of the vestibulocochlear nerve. The other branch is the vestibular nerve.
Within the vestibule, the membranous labyrinth does not quite preserve the form of the bony labyrinth, but consists of two membranous sacs, the utricle, and the saccule.
The membranous labyrinth is also the location for the receptor cells found in the inner ear.
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https://en.wikipedia.org/wiki/FX8010
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The FX8010, is a DSP architecture, designed for realtime audio effects, designed by E-mu, around their E-mu 10K1 chip. One key feature of the architecture, is not providing any branching instructions, but rather running the whole program in a sample locked constant loop, i.e. a constant number of instructions is executed per sample. Instructions are given conditional execution flag akin to some RISC processors (notably the ARM), thus providing a constant runtime.
External links
kxProject documentation page - Some documentation available here
Digital signal processors
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https://en.wikipedia.org/wiki/Matching%20pursuit
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Matching pursuit (MP) is a sparse approximation algorithm which finds the "best matching" projections of multidimensional data onto the span of an over-complete (i.e., redundant) dictionary . The basic idea is to approximately represent a signal from Hilbert space as a weighted sum of finitely many functions (called atoms) taken from . An approximation with atoms has the form
where is the th column of the matrix and is the scalar weighting factor (amplitude) for the atom . Normally, not every atom in will be used in this sum. Instead, matching pursuit chooses the atoms one at a time in order to maximally (greedily) reduce the approximation error. This is achieved by finding the atom that has the highest inner product with the signal (assuming the atoms are normalized), subtracting from the signal an approximation that uses only that one atom, and repeating the process until the signal is satisfactorily decomposed, i.e., the norm of the residual is small,
where the residual after calculating and is denoted by
.
If converges quickly to zero, then only a few atoms are needed to get a good approximation to . Such sparse representations are desirable for signal coding and compression. More precisely, the sparsity problem that matching pursuit is intended to approximately solve is
where is the pseudo-norm (i.e. the number of nonzero elements of ). In the previous notation, the nonzero entries of are . Solving the sparsity problem exactly is NP-hard, which is why approximation methods like MP are used.
For comparison, consider the Fourier transform representation of a signal - this can be described using the terms given above, where the dictionary is built from sinusoidal basis functions (the smallest possible complete dictionary). The main disadvantage of Fourier analysis in signal processing is that it extracts only the global features of the signals and does not adapt to the analysed signals .
By taking an extremely redundant dictionary, we can look
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https://en.wikipedia.org/wiki/Ductus%20reuniens
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The ductus reuniens also the canalis reuniens of Hensen is part of the human inner ear. It connects the lower part of the saccule to the cochlear duct near its vestibular extremity.
See also
Victor Hensen
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https://en.wikipedia.org/wiki/Whangee
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Whangee ( ) refers to any of over forty Asian grasses of the genus Phyllostachys, a genus of bamboos. They are a hardy evergreen plant from Japan, China, and the Himalayas whose woody stems are sometimes used to make canes and umbrella handles. The word derives from the Chinese (Mandarin) huáng lí. It can also refer to a cane made from whangee.
John Steed, the dapper secret agent from television's The Avengers, carried an umbrella with a whangee handle made by British Umbrella maker Swaine Adeney Brigg. Charlie Chaplin's character, The Little Tramp, is famously known for his whangee cane.
The firm of Dunhill created custom smoking pipes and cigarette holders out of whangee, lacquering the surface of the plant stems and adding a black plastic or Bakelite mouthpiece. Terry-Thomas, the well-known British comedic actor, habitually used an 8-inch (20 cm)-long custom black lacquered whangee cigarette holder. It became his trademark and is seen in most of his publicity photographs. His collection included a valuable holder with a spiral of diamonds set in gold over the black lacquered whangee. It was stolen from his dressing room by a young Jimmy Tarbuck and was recovered in a damaged state.
Bertie Wooster in The Inimitable Jeeves (chapter 1) says, "Then bring me my whangee, my yellowest shoes, and the old green Homburg. I'm going into the park to do pastoral dances." The author, P.G. Wodehouse, does not elaborate on the meaning of whangee, assuming that any of his audience would immediately know to what it refers.
Sylvester McCoy used an umbrella with a whangee handle during his early days as The Doctor.
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https://en.wikipedia.org/wiki/Endolymphatic%20duct
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From the posterior wall of the saccule a canal, the endolymphatic duct, is given off; this duct is joined by the ductus utriculosaccularis, and then passes along the aquaeductus vestibuli and ends in a blind pouch (endolymphatic sac) on the posterior surface of the petrous portion of the temporal bone, where it is in contact with the dura mater.
Disorders of the endolymphatic duct include Meniere's Disease and Enlarged Vestibular Aqueduct.
Additional images
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https://en.wikipedia.org/wiki/Lagena%20%28anatomy%29
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The lagena (from Greek λάγηνος : lágēnos for flask) is a structure found in humans and in animals.
In human anatomy
In the ear, the extremities of the ductus cochlearis are closed; the upper is termed the lagena and is attached to the cupula at the upper part of the helicotrema; the lower is lodged in the recessus cochlearis of the vestibule.
In fish and amphibians
The lagena is part of the vestibular system in fish and amphibians. It contains the otoliths asterisci. In fish, the lagena is implicated in hearing and the registration of vertical linear acceleration, in amphibians is the latter only.
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https://en.wikipedia.org/wiki/Space-time%20adaptive%20processing
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Space-time adaptive processing (STAP) is a signal processing technique most commonly used in radar systems. It involves adaptive array processing algorithms to aid in target detection. Radar signal processing benefits from STAP in areas where interference is a problem (i.e. ground clutter, jamming, etc.). Through careful application of STAP, it is possible to achieve order-of-magnitude sensitivity improvements in target detection.
STAP involves a two-dimensional filtering technique using a phased-array antenna with multiple spatial channels. Coupling multiple spatial channels with pulse-Doppler waveforms lends to the name "space-time." Applying the statistics of the interference environment, an adaptive STAP weight vector is formed. This weight vector is applied to the coherent samples received by the radar.
History
The theory of STAP was first published by Lawrence E. Brennan and Irving S. Reed in the early 1970s. At the time of publication, both Brennan and Reed were at Technology Service Corporation (TSC). While it was formally introduced in 1973, it has theoretical roots dating back to 1959.
Motivation and applications
For ground-based radar, cluttered returns tend to be at DC, making them easily discriminated by Moving Target Indication (MTI). Thus, a notch filter at the zero-Doppler bin can be used. Airborne platforms with ownship motion experience relative ground clutter motion dependent on the angle, resulting in angle-Doppler coupling at the input. In this case, 1D filtering is not sufficient, since clutter can overlap the desired target's Doppler from multiple directions. The resulting interference is typically called a "clutter ridge," since it forms a line in the angle-Doppler domain. Narrowband jamming signals are also a source of interference, and exhibit significant spatial correlation. Thus receiver noise and interference must be considered, and detection processors must attempt to maximize the signal-to-interference and noise ratio (SINR).
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https://en.wikipedia.org/wiki/Gauss%27s%20principle%20of%20least%20constraint
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The principle of least constraint is one variational formulation of classical mechanics enunciated by Carl Friedrich Gauss in 1829, equivalent to all other formulations of analytical mechanics. Intuitively, it says that the acceleration of a constrained physical system will be as similar as possible to that of the corresponding unconstrained system.
Statement
The principle of least constraint is a least squares principle stating that the true accelerations of a mechanical system of masses is the minimum of the quantity
where the jth particle has mass , position vector , and applied non-constraint force acting on the mass.
The notation indicates time derivative of a vector function , i.e. position. The corresponding accelerations satisfy the imposed constraints, which in general depends on the current state of the system, .
It is recalled the fact that due to active and reactive (constraint) forces being applied, with resultant , a system will experience an acceleration .
Connections to other formulations
Gauss's principle is equivalent to D'Alembert's principle.
The principle of least constraint is qualitatively similar to Hamilton's principle, which states that the true path taken by a mechanical system is an extremum of the action. However, Gauss's principle is a true (local) minimal principle, whereas the other is an extremal principle.
Hertz's principle of least curvature
Hertz's principle of least curvature is a special case of Gauss's principle, restricted by the three conditions that there are no externally applied forces, no interactions (which can usually be expressed as a potential energy), and all masses are equal. Without loss of generality, the masses may be set equal to one. Under these conditions, Gauss's minimized quantity can be written
The kinetic energy is also conserved under these conditions
Since the line element in the -dimensional space of the coordinates is defined
the conservation of energy may also be written
Dividing
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https://en.wikipedia.org/wiki/Vestibular%20aqueduct
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At the hinder part of the medial wall of the vestibule is the orifice of the vestibular aqueduct, which extends to the posterior surface of the petrous portion of the temporal bone.
It transmits a small vein, and contains a tubular prolongation of the membranous labyrinth, the ductus endolymphaticus, which ends in a cul-de-sac, the endolymphatic sac, between the layers of the dura mater within the cranial cavity.
Pathology
Enlargement of the vestibular aqueduct to greater than 2 mm is associated with enlarged vestibular aqueduct syndrome, a disease entity that is associated with one-sided hearing loss in children. The diagnosis can be made by high resolution CT or MRI, with comparison to the adjacent posterior semicircular canal. If the vestibular aqueduct is larger in size, and the clinical presentation is consistent, the diagnosis can be made. Treatment is with mechanical hearing implants. There is an association with Pendred syndrome and incomplete cochlear partition (so called "Mondini dysplasia").
Additional images
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https://en.wikipedia.org/wiki/Transverse%20mass
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The transverse mass is a useful quantity to define for use in particle physics as it is invariant under Lorentz boost along the z direction. In natural units, it is:
where the z-direction is along the beam pipe and so
and are the momentum perpendicular to the beam pipe and
is the (invariant) mass.
This definition of the transverse mass is used in conjunction with the definition of the (directed) transverse energy
with the transverse momentum vector . It is easy to see that for vanishing mass () the three quantities are the same: .
The transverse mass is used together with the rapidity, transverse momentum and polar angle in the parameterization of the four-momentum of a single particle:
Using these definitions (in particular for ) gives for the mass of a two particle system:
Looking at the transverse projection of this system (by setting ) gives:
These are also the definitions that are used by the software package ROOT, which is commonly used in high energy physics.
Transverse mass in two-particle systems
Hadron collider physicists use another definition of transverse mass (and transverse energy), in the case of a decay into two particles. This is often used when one particle cannot be detected directly but is only indicated by missing transverse energy. In that case, the total energy is unknown and the above definition cannot be used.
where is the transverse energy of each daughter, a positive quantity defined using its true invariant mass as:
,
which is coincidentally the definition of the transverse mass for a single particle given above.
Using these two definitions, one also gets the form:
(but with slightly different definitions for !)
For massless daughters, where , we again have , and the transverse mass of the two particle system becomes:
where is the angle between the daughters in the transverse plane.
The distribution of has an end-point at the invariant mass of the system with . This has been used to determine the mass at the Tevatro
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https://en.wikipedia.org/wiki/Nitrate%20reductase
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Nitrate reductases are molybdoenzymes that reduce nitrate (NO) to nitrite (NO). This reaction is critical for the production of protein in most crop plants, as nitrate is the predominant source of nitrogen in fertilized soils.
Types
Eukaryotic
Eukaryotic nitrate reductases are part of the sulfite oxidase family of molybdoenzymes. They transfer electrons from NADH or NADPH to nitrate.
Prokaryotic
Prokaryotic nitrate reductases belong to the DMSO reductase family of molybdoenzymes and have been classified into three groups, assimilatory nitrate reductases (Nas), respiratory nitrate reductase (Nar), and periplasmic nitrate reductases (Nap). The active site of these enzymes is a Mo ion that is bound to the four thiolate functions of two pterin molecules. The coordination sphere of the Mo is completed by one amino-acid side chain and oxygen and/or sulfur ligands. The exact environment of the Mo ion in certain of these enzymes (oxygen versus sulfur as a sixth molybdenum ligand) is still debated. The Mo is covalently attached to the protein by a cysteine ligand in Nap, and an aspartate in Nar.
Structure
Prokaryotic nitrate reductases have two major types, transmembrane nitrate reductases and periplasmic nitrate reductases. The transmembrane nitrate reductase (NAR) does proton translocation and can contribute to the generation of ATP by the proton motive force. The periplasmic nitrate reductase (NAP) does not do proton translocation and does not contribute to the proton motive force.
The transmembrane respiratory nitrate reductase is composed of three subunits; an 1 alpha, 1 beta and 2 gamma. It is the second nitrate reductase enzyme which it can substitute for the NRA enzyme in Escherichia coli allowing it to use nitrate as an electron acceptor during anaerobic respiration. A transmembrane nitrate reductase that can function as a proton pump (similar to the case of anaerobic respiration) has been discovered in a diatom Thalassiosira weissflogii.
The nitrate reduct
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https://en.wikipedia.org/wiki/Stria%20vascularis%20of%20cochlear%20duct
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The stria vascularis of the cochlear duct is a capillary loop in the upper portion of the spiral ligament (the outer wall of the cochlear duct). It produces endolymph for the scala media in the cochlea.
Structure
The stria vascularis is part of the lateral wall of the cochlear duct. It is a somewhat stratified epithelium containing primarily three cell types:
marginal cells, which are involved in K+ transport, and line the endolymphatic space of the scala media.
intermediate cells, which are pigment-containing cells scattered among capillaries.
basal cells, which separate the stria vascularis from the underlying spiral ligament. They are connected to basal cells with gap junctions.
The stria vascularis also contains pericytes, melanocytes, and endothelial cells. It also contains intraepithelial capillaries - it is the only epithelial tissue that is not avascular (completely lacking blood vessels and lymphatic vessels).
Function
The stria vascularis produces endolymph for the scala media, one of the three fluid-filled compartments of the cochlea. This maintains the ion balance of the endolymph that surround inner hair cells and outer hair cells of the organ of Corti. It secretes lots of K+, and may also secrete H+.
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https://en.wikipedia.org/wiki/Nuclear%20power%20by%20country
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Nuclear power plants operate in 32 countries and generate about a tenth of the world's electricity.
Most are in Europe, North America, East Asia and South Asia.
The United States is the largest producer of nuclear power, while France has the largest share of electricity generated by nuclear power, at about 70%.
China has the fastest growing nuclear power programme with 16 new reactors under construction, followed by India, which has 8 under construction.
Some countries operated nuclear reactors in the past but have no operating nuclear plants.
Among them, Italy closed all of its nuclear stations by 1990 and nuclear power has since been discontinued because of the 1987 referendums.
Kazakhstan is planning to reintroduce nuclear power in the future. Belarus began operating one unit of its first nuclear power plant in June 2021 and was expecting to bring the second unit into operation in 2023.
Germany completed the shut down of its nuclear fleet on April 15, 2023 and any restart has been ruled out on technical grounds. Austria (Zwentendorf Nuclear Power Plant) and the Philippines (Bataan Nuclear Power Plant) never started to use their first nuclear plants that were completely built.
Sweden and Belgium originally had phase-out policies however they have now moved away from their original plans. The Philippines relaunched their nuclear programme on February 28, 2022 and may soon operate the mothballed Bataan Plant.
Due to financial, political and technical reasons, Cuba, Libya and Poland never completed the construction of their first nuclear plants, and Australia, Azerbaijan, Georgia, Ghana, Ireland, Kuwait, Oman, Peru and Singapore never built their planned first nuclear plants. Some of these countries are still planning to introduce nuclear power. As of 2020, Poland was in advanced planning phase for 1.5 GW and planned to have up to 9 GW by 2040.
Hong Kong has no nuclear power plants within its boundary, but imports 80% of the electricity generated from Daya Ba
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https://en.wikipedia.org/wiki/Osseous%20spiral%20lamina
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The osseous spiral lamina is a bony shelf or ledge which projects from the modiolus into the interior of the canal, and, like the canal, takes two-and-three-quarter turns around the modiolus.
It reaches about half-way toward the outer wall of the tube, and partially divides its cavity into two passages or scalae, of which the upper is named the scala vestibuli, while the lower is termed the scala tympani.
Near the summit of the cochlea the lamina ends in a hook-shaped process, the hamulus laminae spiralis; this assists in forming the boundary of a small opening, the helicotrema, through which the two scalae communicate with each other.
From the spiral canal of the modiolus numerous canals pass outward through the osseous spiral lamina as far as its free edge.
In the lower part of the first turn a second bony lamina, the secondary spiral lamina, projects inward from the outer wall of the bony tube; it does not, however, reach the primary osseous spiral lamina, so that if viewed from the vestibule a narrow fissure, the vestibule fissure, is seen between them.
See also
Basilar membrane
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https://en.wikipedia.org/wiki/Endolymphatic%20sac
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From the posterior wall of the saccule a canal, the endolymphatic duct, is given off; this duct is joined by the utriculosaccular duct, and then passes along the vestibular aqueduct and ends in a blind pouch, the endolymphatic sac, on the posterior surface of the petrous portion of the temporal bone, where it is in contact with the dura mater. Studies suggest that the endolymphatic duct and endolymphatic sac perform both absorptive and secretory, as well as phagocytic and immunodefensive, functions.
Neoplasms of the endolymphatic sac are very rare tumors.
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https://en.wikipedia.org/wiki/LED%20circuit
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In electronics, an LED circuit or LED driver is an electrical circuit used to power a light-emitting diode (LED). The circuit must provide sufficient current to light the LED at the required brightness, but must limit the current to prevent damaging the LED. The voltage drop across an LED is approximately constant over a wide range of operating current; therefore, a small increase in applied voltage greatly increases the current. Very simple circuits are used for low-power indicator LEDs. More complex, current source circuits are required when driving high-power LEDs for illumination to achieve correct current regulation.
Basic circuit
The simplest circuit to drive an LED is through a series resistor. It is commonly used for indicators and digital displays in many consumer appliances. However, this circuit is not energy-efficient, because energy is dissipated in the resistor as heat.
An LED has a voltage drop specified at the intended operating current. Ohm's law and Kirchhoff's circuit laws are used to calculate the appropriate resistor value, by subtracting the LED voltage drop from the supply voltage and dividing by the desired operating current. With a sufficiently high supply voltage, multiple LEDs in series can be powered with one resistor.
If the supply voltage is close or equal to the LED forward voltage, then no reasonable value for the resistor can be calculated, so some other method of current limiting is used.
Power source considerations
The voltage versus current characteristics of an LED is similar to any diode. Current is approximately an exponential function of voltage according to the Shockley diode equation, and a small voltage change may result in a large change in current. If the voltage is below or equal to the threshold no current flows and the result is an unlit LED. If the voltage is too high, the current will exceed the maximum rating, overheating and potentially destroying the LED.
LED drivers are designed to handle fluctuation load,
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https://en.wikipedia.org/wiki/Digital%20channel%20election
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A digital channel election was the process by which television stations in the United States chose which physical radio-frequency TV channel they would permanently use after the analog shutdown in 2009. The process was managed and mandated by the Federal Communications Commission for all full-power TV stations. Low-powered television (LPTV) stations are going through a somewhat different process, and are also allowed to flash-cut to digital.
Process
Stations could choose to keep their initial digital TV channel allocation, do a flash-cut to their former analog TV channel, or attempt to select another channel, often an analog channel or pre-transition digital channel from another station that had been orphaned. Stations on channels 52 to 69 did not have the first option, as the FCC and then the U.S. Congress revoked them from the bandplan.
Many stations have chosen to keep their new channels permanently, after being forced to buy all new transmitters and television antennas. In some cases where the station's current analog tower could not handle the stress of the new digital antenna's weight and wind load, station owners had to construct entirely new broadcast towers in order to comply with the FCC's DTV mandate.
Most broadcasters were bitter at having to purchase digital equipment and broadcast a digital signal when very few homeowners had digital television sets. The FCC allowed broadcasters the opportunity to petition the Federal Communications Commission (FCC) for special temporary authority (STA) to operate their digital facilities at low power, thereby allowing broadcasters additional time in which to purchase their full-power digital facilities. However, the FCC gave a stern July 2006 deadline for all full-power television stations to at least replicate 80% of their current analog coverage area, or run the risk of losing protection from encroachment by other stations.
Most stations made an election in the first round, and most of those received
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https://en.wikipedia.org/wiki/Vieraella
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Vieraella is an extinct genus of frog from the Lower Jurassic (Early Pliensbachian to Toarcian) Roca Blanca Formation of Argentina, and one of the oldest true frogs known. This genus is known by a single excepcionally well preserved specimen, P.V.L. 2188, with at least eight presacrals vertebrae, free ribs, ulna and radius not fused, bony skull with some discoglossid characters.
Description
Despite living around 188 million years ago, Vieraella was anatomically very similar to modern frogs. For example, its hind legs were adapted for jumping, and the skull already possessed the lattice-like form found in modern species. It was, however, an unusually small frog, measuring only in length. Although older frog-like creatures are known, such as Triadobatrachus, these possessed many primitive characteristics, and cannot be said to be "true" frogs.
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https://en.wikipedia.org/wiki/Triadobatrachus
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Triadobatrachus is an extinct genus of salientian frog-like amphibians, including only one known species, Triadobatrachus massinoti. It is the oldest member of the frog lineage known, and an excellent example of a transitional fossil. It lived during the Early Triassic about 250 million years ago, in what is now Madagascar.
Triadobatrachus was long, and still retained many primitive characteristics, such as possessing at least 26 vertebrae, where modern frogs have only four to nine. At least 10 of these vertebrae formed a short tail, which the animal may have retained as an adult. It probably swam by kicking its hind legs, although it could not jump, as most modern frogs can. Its skull resembled that of modern frogs, consisting of a latticework of thin bones separated by large openings.
This creature, or a relative, evolved eventually into modern frogs, the earliest example of which is Prosalirus, millions of years later in the Early Jurassic.
It was first discovered in the 1930s, when Adrien Massinot, near the village of Betsiaka in northern Madagascar, found an almost complete skeleton in the Induan Middle Sakamena Formation of the Sakamena Group. The animal must have fossilized soon after its death, because all bones lay in their natural anatomical position. Only the anterior part of the skull and the ends of the limbs were missing. This fossil was initially described under the name Protobatrachus massinoti by the French paleontologist Jean Piveteau in 1936. Much more detailed description were published more recently.
Although it was found in marine deposits, the general structure of Triadobatrachus shows that it probably lived for part of the time on land and breathed air. Its proximity to the mainland is further borne out by the remains of terrestrial plants found with it, and because most extant amphibians do not tolerate saltwater, and that this saltwater intolerance was probably present in the earliest lissamphibians.
Gallery
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https://en.wikipedia.org/wiki/Ethnolichenology
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Ethnolichenology is the study of the relationship between lichens and people. Lichens have and are being used for many different purposes by human cultures across the world. The most common human use of lichens is for dye, but they have also been used for medicine, food and other purposes.
Lichens for dye
Lichens are a common source of natural dyes. The lichen dye is usually extracted by either boiling water or ammonia fermentation. Although usually called ammonia fermentation, this method is not actually a fermentation and involves letting the lichen steep in ammonia (traditionally urine) for at least two to three weeks.
In North America the most significant lichen dye is Letharia vulpina. Indigenous people through most of this lichen's range in North America traditionally make a yellow dye from this lichen by boiling it in water.
Many of the traditional dyes of the Scottish Highlands were made from lichens including red dyes from the cudbear lichen, Lecanora tartarea, the common orange lichen, Xanthoria parietina, and several species of leafy Parmelia lichens. Brown or yellow lichen dyes (called crottle or crotal), made from Parmelia saxatilis scraped off rocks, and red lichen dyes (called corkir) were used extensively to produce tartans.
Purple dyes from lichens were historically very important throughout Europe from the 15th to 17th centuries. They were generally extracted from Roccella spp. lichens imported from the Canary Islands, Cape Verde Islands, Madagascar, or India. These lichens, and the dye extracted from them, are called orchil (variants archil, orchilla). The same dye was also produced from Ochrolechia spp. lichens in Britain and was called cudbear. Both Roccella spp. and Ochrolechia spp. contain the lichen substance orcin, which converts into the purple dye orcein in the ammonia fermentation process.
Litmus, a water-soluble pH indicator dye mixture, is extracted from Roccella species.
Lichens for medicine
Many lichens have been used medicinall
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https://en.wikipedia.org/wiki/Miroslav%20Fiedler
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Miroslav Fiedler (7 April 1926 – 20 November 2015) was a Czech mathematician known for his contributions to linear algebra, graph theory and algebraic graph theory.
His article, "Algebraic Connectivity of Graphs", published in the Czechoslovak Math Journal in 1973, established the use of the eigenvalues of the Laplacian matrix of a graph to create tools for measuring algebraic connectivity in algebraic graph theory. Fiedler is honored by the Fiedler eigenvalue (the second smallest eigenvalue of the graph Laplacian), with its associated Fiedler eigenvector, as the names for the quantities that characterize algebraic connectivity. Since Fiedler's original contribution, this structure has become essential to large areas of research in network theory, flocking, distributed control, clustering, multi-robot applications and image segmentation.
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https://en.wikipedia.org/wiki/Borel%20hierarchy
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In mathematical logic, the Borel hierarchy is a stratification of the Borel algebra generated by the open subsets of a Polish space; elements of this algebra are called Borel sets. Each Borel set is assigned a unique countable ordinal number called the rank of the Borel set. The Borel hierarchy is of particular interest in descriptive set theory.
One common use of the Borel hierarchy is to prove facts about the Borel sets using transfinite induction on rank. Properties of sets of small finite ranks are important in measure theory and analysis.
Borel sets
The Borel algebra in an arbitrary topological space is the smallest collection of subsets of the space that contains the open sets and is closed under countable unions and complementation. It can be shown that the Borel algebra is closed under countable intersections as well.
A short proof that the Borel algebra is well-defined proceeds by showing that the entire powerset of the space is closed under complements and countable unions, and thus the Borel algebra is the intersection of all families of subsets of the space that have these closure properties. This proof does not give a simple procedure for determining whether a set is Borel. A motivation for the Borel hierarchy is to provide a more explicit characterization of the Borel sets.
Boldface Borel hierarchy
The Borel hierarchy or boldface Borel hierarchy on a space X consists of classes , , and for every countable ordinal greater than zero. Each of these classes consists of subsets of X. The classes are defined inductively from the following rules:
A set is in if and only if it is open.
A set is in if and only if its complement is in .
A set is in for if and only if there is a sequence of sets such that each is in for some and .
A set is in if and only if it is both in and in .
The motivation for the hierarchy is to follow the way in which a Borel set could be constructed from open sets using complementation and countable un
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https://en.wikipedia.org/wiki/Line%E2%80%93sphere%20intersection
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In analytic geometry, a line and a sphere can intersect in three ways:
No intersection at all
Intersection in exactly one point
Intersection in two points.
Methods for distinguishing these cases, and determining the coordinates for the points in the latter cases, are useful in a number of circumstances. For example, it is a common calculation to perform during ray tracing.
Calculation using vectors in 3D
In vector notation, the equations are as follows:
Equation for a sphere
: points on the sphere
: center point
: radius of the sphere
Equation for a line starting at
: points on the line
: origin of the line
: distance from the origin of the line
: direction of line (a non-zero vector)
Searching for points that are on the line and on the sphere means combining the equations and solving for , involving the dot product of vectors:
Equations combined
Expanded and rearranged:
The form of a quadratic formula is now observable. (This quadratic equation is an instance of Joachimsthal's equation.)
where
Simplified
Note that in the specific case where is a unit vector, and thus , we can simplify this further to (writing instead of to indicate a unit vector):
If , then it is clear that no solutions exist, i.e. the line does not intersect the sphere (case 1).
If , then exactly one solution exists, i.e. the line just touches the sphere in one point (case 2).
If , two solutions exist, and thus the line touches the sphere in two points (case 3).
See also
Intersection_(geometry)#A_line_and_a_circle
Analytic geometry
Line–plane intersection
Plane–plane intersection
Plane–sphere intersection
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https://en.wikipedia.org/wiki/Azinphos-methyl
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Azinphos-methyl (Guthion) (also spelled azinophos-methyl) is a broad spectrum organophosphate insecticide manufactured by Bayer CropScience, Gowan Co., and Makhteshim Agan. Like other pesticides in this class, it owes its insecticidal properties (and human toxicity) to the fact that it is an acetylcholinesterase inhibitor (the same mechanism is responsible for the toxic effects of the V-series nerve agent chemical weapons). It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.
History and uses
Azinphos-methyl is a neurotoxin derived from nerve agents developed during World War II. It was first registered in the US in 1959 as an insecticide and is also used as active ingredient in organophosphate (OP) pesticides. It is not registered for consumer or residential use. It has been linked to health problems of farmers who apply it, and the U.S. Environmental Protection Agency (EPA) considered a denial of reregistration, citing, “concern to farm workers, pesticide applicators, and aquatic ecosystems. The use of AZM has been fully banned in the USA since 30 September 2013, ending a phase-out period of twelve years.
Azinphos-methyl has been banned in the European Union since 2006 and in Turkey since 2013.
The New Zealand Environmental Risk Management Authority made a decision to phase out azinphos-methyl over a five-year period starting from 2009. In 2014, it was still used in Australia and partly in New Zealand.
Available forms
AzM is often used as active ingredient in organophosphate pesticides like Guthion, Gusathion (GUS), Gusathion-M, Crysthyron, Cotnion, Cotnion-methyl, Metriltrizotion, Carfene, Bay 9027, Bay 17147, and R-1852. This is why Guthion is often used as a nickname for AzM.
Studies have shown that pure AzM is
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https://en.wikipedia.org/wiki/Beta%20globulin
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Beta globulins are a group of globular proteins in plasma that are more mobile in alkaline or electrically charged solutions than gamma globulins, but less mobile than alpha globulins.
Examples of beta globulins include:
beta-2 microglobulin
plasminogen
angiostatins
properdin
sex hormone-binding globulin
transferrin
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https://en.wikipedia.org/wiki/Java%204K%20Game%20Programming%20Contest
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The Java 4K Game Programming Contest, also known as Java 4K and J4K, is an informal contest that was started by the Java Game Programming community to challenge their software development abilities.
Concept
The goal of the contest is to develop the best game possible within four kibibytes (4096 bytes) of data. While the rules originally allowed for nearly any distribution method, recent years have required that the games be packaged as either an executable JAR file, a Java Webstart application, or a Java Applet, and now only an applet.
Because the Java class file format incurs quite a bit of overhead, creating a complete game in 4K can be quite a challenge. As a result, contestants must choose how much of their byte budget they wish to spend on graphics, sound, and gameplay. Finding the best mix of these factors can be extremely difficult. Many new entrants believe that impressive graphics alone are enough to carry a game. However, entries with more modest graphics and focus on gameplay have regularly scored higher than such technology demonstrations.
Prizes
When first conceived, the "prize" for winning the contest was a bundle of "Duke Dollars", a virtual currency used on Sun Microsystems' Java forums. This currency could theoretically be redeemed for physical prizes such as watches and pens. The artificial currency was being downplayed by the introduction of the 4K contest, thus leaving no real prize at all. While there has been some discussion of providing prizes for the contest, it has continued to thrive without them.
Spin-offs
Following the creation of the Java4K contest, spin-offs targeting 8K, 16K, or a specific API like LWJGL have been launched, usually without success. While there has been a great deal of debate on why the Java 4K contest is so successful, the consensus from the contestants seems to be that it provides a very appealing challenge: not only do the entrants get the chance to show off how much they know about Java programming, but th
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https://en.wikipedia.org/wiki/Yotari
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The yotari mouse is an autosomal recessive mutant. It has a mutated disabled homolog 1 (Dab1) gene. This mutant mouse is recognized by unstable gait ("Yota-ru" in Japanese means "unstable gait") and tremor and by early deaths around the time of weaning. The cytoarchitectures of cerebellar and cerebral cortices and hippocampal formation of the yotari mouse are abnormal. These malformations resemble those of reeler mouse.
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https://en.wikipedia.org/wiki/Australian%20Bird%20Count
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The Australian Bird Count (ABC) was a project of the Royal Australasian Ornithologists Union (RAOU). Following the first and successful Atlas of Australian Birds project, which led to the publication of a book on the distribution of Australian birds in 1984, it was suggested by Ken Rogers that the RAOU should next look at bird migration and other movements in Australia. Methodology for a suitable project involving volunteers was worked out through experimental fieldwork and a workshop on ‘Monitoring the Populations and Movements of Australian Birds’.
A project manager, [Stephen Ambrose], was appointed and project fieldwork ran from January 1989 to August 1995. Some 950 volunteer observers carried out 79,000 surveys, for fixed 20-minute periods in 1700 three-hectare locations over Australia.
Project management started at the Australian Museum in Sydney and was later moved to the RAOU National Office in Melbourne. Financial support came at first from the Australian Nature Conservation Agency and subsequently from BP Australia which pledged A$260,000 to the project over five years.
While much of the data has yet to be analysed, significant seasonal movements of several species of birds, (demonstrated through geographical shifts in seasonal abundance) have been quantified. A report on some of the findings of the project was published as a supplement to the RAOU's magazine Wingspan in 1999.
See also
Aussie Backyard Bird Count
BioBlitz ("24-hour inventory")
Breeding Bird Survey
Christmas Bird Count (CBC) (in the Western Hemisphere)
Systematic Census of Australian Plants
Tucson Bird Count (TBC) (in Arizona in the US)
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https://en.wikipedia.org/wiki/Microwave%20transmission
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Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz (1 m - 1 mm wavelength) of the electromagnetic spectrum. Microwave signals are normally limited to the line of sight, so long-distance transmission using these signals requires a series of repeaters forming a microwave relay network. It is possible to use microwave signals in over-the-horizon communications using tropospheric scatter, but such systems are expensive and generally used only in specialist roles.
Although an experimental microwave telecommunication link across the English Channel was demonstrated in 1931, the development of radar in World War II provided the technology for practical exploitation of microwave communication. During the war, the British Army introduced the Wireless Set No. 10, which used microwave relays to multiplex eight telephone channels over long distances. A link across the English Channel allowed General Bernard Montgomery to remain in continual contact with his group headquarters in London.
In the post-war era, the development of microwave technology was rapid, which led to the construction of several transcontinental microwave relay systems in North America and Europe. In addition to carrying thousands of telephone calls at a time, these networks were also used to send television signals for cross-country broadcast, and later, computer data. Communication satellites took over the television broadcast market during the 1970s and 80s, and the introduction of long-distance fibre optic systems in the 1980s and especially 90s led to the rapid rundown of the relay networks, most of which are abandoned.
In recent years, there has been an explosive increase in use of the microwave spectrum by new telecommunication technologies such as wireless networks, and direct-broadcast satellites which broadcast television and radio directly into consumers' homes. Larger line-of-sight links are
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https://en.wikipedia.org/wiki/Gated%20reverb
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Gated reverb or gated ambience is an audio processing technique that combines strong reverb and a noise gate that cuts the tail of the reverb. The effect is typically applied to recordings of drums (or live sound reinforcement of drums in a PA system) to make the hits sound powerful and "punchy" while keeping the overall mix clean and transparent sounding.
As one of the more prominent effects in many British pop and rock songs of the 1980s, it was brought to mainstream attention in 1979 by producer Steve Lillywhite and engineer Hugh Padgham while working on Peter Gabriel's self-titled third solo album, after Phil Collins played drums without using cymbals at London's Townhouse Studios. The effect is most quintessentially demonstrated in Collins' hit song "In the Air Tonight".
Unlike many reverberation or delay effects, the gated reverb effect does not try to emulate any kind of reverb that occurs in nature. In addition to drums, the effect has occasionally been applied to vocals.
History
Producer Steve Lillywhite claimed he first experimented the "ambience thing" on drums during the recording of Siouxsie and the Banshees' album The Scream (1978), when drummer Kenny Morris played without using cymbals on several songs. Lillywhite explained to journalist John Robb: "When you listen, you can hear elements of this gated room sound, big compressed room sound that I did on the Banshees." He also listed his production's work on Psychedelic Furs's single "Sister Europe"; this was "all done before the Peter Gabriel album". Lillywhite recognized that the gated reverb drum sound first really showed its head in that form during the recording of the Peter Gabriel 1980 album with engineer Hugh Padgham.
Lillywhite's and Padgham's work on Peter Gabriel 3 was bookended with their work on XTC's Drums and Wires (1979) and Black Sea (1980). In this period they perfected their technique on Terry Chambers' drums, which can be heard most distinctively on Black Sea (particularly song
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https://en.wikipedia.org/wiki/Fragrance%20extraction
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Fragrance extraction refers to the separation process of aromatic compounds from raw materials, using methods such as distillation, solvent extraction, expression, sieving, or enfleurage. The results of the extracts are either essential oils, absolutes, concretes, or butters, depending on the amount of waxes in the extracted product.
To a certain extent, all of these techniques tend to produce an extract with an aroma that differs from the aroma of the raw materials. Heat, chemical solvents, or exposure to oxygen in the extraction process may denature some aromatic compounds, either changing their odour character or rendering them odourless, and the proportion of each aromatic component that is extracted can differ.
Maceration/solvent extraction
Certain plant materials contain too little volatile oil to undergo expression, or their chemical components are too delicate and easily denatured by the high heat used in steam distillation. Instead, the oils are extracted using their solvent properties.
Organic solvent extraction
Organic solvent extraction is the most common and most economically important technique for extracting aromatics in the modern perfume industry. Raw materials are submerged and agitated in a solvent that can dissolve the desired aromatic compounds. Commonly used solvents for maceration/solvent extraction include hexane, and dimethyl ether.
In organic solvent extraction, aromatic compounds as well as other hydrophobic soluble substances such as wax and pigments are also obtained. The extract is subjected to vacuum processing, which removes the solvent for re-use. The process can last anywhere from hours to months. Fragrant compounds for woody and fibrous plant materials are often obtained in this matter as are all aromatics from animal sources. The technique can also be used to extract odorants that are too volatile for distillation or easily denatured by heat. The remaining waxy mass is known as a concrete, which is a mixture of essential oil,
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https://en.wikipedia.org/wiki/POTS%20codec
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A POTS codec is a type of audio coder-decoder (codec) that uses digital signal processing to transmit audio digitally over standard telephone lines (plain old telephone service, POTS) at a higher level of audio quality than the telephone line would normally provide in its analog mode. The POTS codec is one of a family of broadcast codecs differentiated by the type of telecommunications circuit used for transmission. The ISDN codec, which instead uses ISDN lines, and the IP codec which uses private or public IP networks are also common.
Primarily used in broadcast engineering to link remote broadcast locations to the host studio, a hardware codec, implemented with digital signal processing, is used to compress the audio data enough to travel through a pair of a 33.6k modems.
POTS codecs have the disadvantages of being restricted to relatively low bit rates and being susceptible to variable line quality. ISDN and IP codecs have the advantage of being natively digital, and operate at much higher bitrates, which results in fewer compression artifacts. Special lines must be run to a location, however, and must be ordered well in advance of the event so that there is ample time for installation of equipment. Since POTS lines are almost universally available, the POTS codec can be set up nearly anywhere with little or no notice.
Uses
The main use of a broadcast codec is for remote broadcasting by radio stations.
Functions
Codecs usually come in two types of units: rackmount for the studio and portable for the remote. Audio can be sent in either direction, and most can also pass low-speed non-audio data, allowing the remote DJ to control broadcast automation or other studio equipment via RS-232. Many have an automatic redial if the line should become disconnected. The remote unit usually has some basic mixer functions, while the studio unit usually has some kind of digital output.
Some codecs can be configured to use ISDN, POTS or IP rather than requiring a differe
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https://en.wikipedia.org/wiki/Bil%20Herd
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Bil Herd is a computer engineer who created several designs for 8-bit home computers while working for Commodore Business Machines in the early to mid-1980s.
Biography
He attended the Indiana school system. Herd did not have a college degree, and did not graduate high school, though he was working as an engineer by the age of 20.
Military service
Military service:
1977–1980: 238th Cavalry - 38th Division Indiana Army National Guard
1980–1982: 103rd Medical Battalion - 28th Division Pennsylvania Army National Guard
1981: Army Commendation Medal for meritorious service.
Working for Commodore
After first acting as the principal engineer on the Commodore Plus/4, C16/116, C264, and C364 machines, Herd designed the significantly more successful Commodore 128, a dual-CPU, triple-OS, compatible successor to the Commodore 64. Prior to the C128, Herd had done the initial architecture of the Commodore LCD computer, which was not released.
After Commodore
After leaving Commodore, Herd continued to design faster and more powerful computers with emphasis on machine vision and is a co-author on a patent involving n-dimensional pattern matching. He also designed an ultrasonic backup sensor for vehicles while working for Indian Valley Mfg. in 1986, a feature found on many modern vehicles today.
Voluntary health care work:
1989–1996: Fellowship First Aid Squad / Mount Laurel EMS Inc. Highest rank: Captain (also served as president)
1991–1995: Cooper Trauma Center - Camden, NJ: Trauma Technician
Herd has undertaken an entrepreneurial role and is owner of several small companies. As for recent low-level computer hacking, he did a "cameo appearance" by contributing a snippet of sprite logic code to the C64 DTV product designed by Jeri Ellsworth.
Herd appeared in and narrated the documentary "Growing the 8 Bit Generation" (a.k.a. "The Commodore Wars") about the early days of Commodore and the home computers explosion. Subsequently, he narrated the documentary "Easy to l
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https://en.wikipedia.org/wiki/Race%20to%20Space
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Race to Space is a 2001 fictional American family drama film. The film was shot on location at Cape Canaveral and Cocoa Beach and Edwards AFB in cooperation with NASA and the U.S. Air Force.
Plot
During the 1960s space race between the United States and the Soviet Union, Dr. Wilhelm von Huber, a top NASA scientist, relocates to Cape Canaveral with his 12-year-old son, Billy. Their relationship has become strained in the wake of the recent death of Billy's mother, and the ever-widening gap between father and son has become obvious.
Billy finds his father old-fashioned and boring. He wants to lead an exciting life: to be a hero like the astronaut Alan Shepard.
However, Billy's life takes an exciting turn when he is hired by Dr. Donni McGuinness, the Director of Veterinary Sciences, to help train the chimpanzees for NASA space missions. Billy begins to develop a close bond with one particular chimpanzee named Mac. With Billy's help and companionship, Mac is chosen to become the first American astronaut launched into space.
All seems like a wonderful game until Billy realizes that his new friend is being prepared to be hurled hundreds of miles into orbit on a historical mission - and that someone at NASA is about to sabotage the mission. Mac's big chance to explore the farthest frontier and hurtle America ahead in the race to space might easily cost him his life.
Cast
James Woods as Dr. Wilhelm von Huber
Annabeth Gish as Dr. Donni McGuinness
Alex D. Linz as Wilhelm 'Billy' von Huber
William Devane as Roger Thornhill
William Atherton as Ralph Stanton
Wesley Mann as Rudolph
Mark Moses as Alan Shepard
Tony Jay as Narrator
Reception
Common Sense Media rated the film 3 out of 5 stars.
See also
Monkeys and apes in space
Ham, the first chimpanzee in space
Enos, the second chimpanzee in space and only one to orbit the Earth
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https://en.wikipedia.org/wiki/Neutral%20mutation
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Neutral mutations are changes in DNA sequence that are neither beneficial nor detrimental to the ability of an organism to survive and reproduce. In population genetics, mutations in which natural selection does not affect the spread of the mutation in a species are termed neutral mutations. Neutral mutations that are inheritable and not linked to any genes under selection will be lost or will replace all other alleles of the gene. That loss or fixation of the gene proceeds based on random sampling known as genetic drift. A neutral mutation that is in linkage disequilibrium with other alleles that are under selection may proceed to loss or fixation via genetic hitchhiking and/or background selection.
While many mutations in a genome may decrease an organism’s ability to survive and reproduce, also known as fitness, those mutations are selected against and are not passed on to future generations. The most commonly-observed mutations that are detectable as variation in the genetic makeup of organisms and populations appear to have no visible effect on the fitness of individuals and are therefore neutral. The identification and study of neutral mutations has led to the development of the neutral theory of molecular evolution, which is an important and often-controversial theory that proposes that most molecular variation within and among species is essentially neutral and not acted on by selection. Neutral mutations are also the basis for using molecular clocks to identify such evolutionary events as speciation and adaptive or evolutionary radiations.
History
Charles Darwin commented on the idea of neutral mutation in his work, hypothesizing that mutations that do not give an advantage or disadvantage may fluctuate or become fixed apart from natural selection. "Variations neither useful nor injurious would not be affected by natural selection, and would be left either a fluctuating element, as perhaps we see in certain polymorphic species, or would ultimately become
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https://en.wikipedia.org/wiki/Ragone%20plot
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A Ragone plot ( ) is a plot used for comparing the energy density of various energy-storing devices. On such a chart the values of specific energy (in W·h/kg) are plotted versus specific power (in W/kg). Both axes are logarithmic, which allows comparing performance of very different devices. Ragone plots can reveal information about gravimetric energy density, but do not convey details about volumetric energy density.
The Ragone plot was first used to compare performance of batteries. However, it is suitable for comparing any energy-storage devices, as well as energy devices such as engines, gas turbines, and fuel cells. The plot is named after David V. Ragone.
Conceptually, the vertical axis describes how much energy is available per unit mass, while the horizontal axis shows how quickly that energy can be delivered, otherwise known as power per unit mass. A point in a Ragone plot represents a particular energy device or technology.
The amount of time (in hours) during which a device can be operated at its rated power is given as the ratio between the specific energy (Y-axis) and the specific power (X-axis). This is true regardless of the overall scale of the device, since a larger device would have proportional increases in both power and energy. Consequently, the iso curves (constant operating time) in a Ragone plot are straight lines.
For electrical systems, the following equations are relevant:
where V is voltage (V), I electric current (A), t time (s) and m mass (kg).
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https://en.wikipedia.org/wiki/Tripedalism
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Tripedalism (from the Latin tri = three + ped = foot) is locomotion by the use of three limbs. It has been said that parrots (Psittaciformes) display tripedalism during climbing gaits, which was tested and proven in a 2022 paper on the subject, making parrots the only creatures to truly use tripedal forms of locomotion. Tripedal gaits were also observed by K. Hunt in primates. This is usually observed when the animal is using one limb to grasp a carried object and is thus a non-standard gait. Apart from climbing in parrots, there are no known animal behaviours where the same three extremities are routinely used to contact environmental supports, although the movement of some macropods such as kangaroos, which can alternate between resting their weight on their muscular tails and their two hind legs and hop on all three, may be an example of tripedal locomotion in animals. There are also the tripod fish. Several species of these fish rest on the ocean bottom on two rays from their two pelvic fins and one ray from their caudal fin.
Real-world tripedalism is rare, in contrast to the common bipedalism of two-legged animals and quadrupedalism of four-legged animals. The code for bilateral symmetry seems to have become entrenched very early in evolution, appearing even before appendages like legs, fins or flippers had evolved; with that template came a built-in bias toward even-numbered limb configurations.
Quadrupedal amputees and mutations
There are some three-legged creatures in the world today, namely four-legged animals (such as pet dogs and cats) which have had one limb amputated. With proper medical treatment most of these injured animals can go on to live fairly normal lives, despite being artificially tripedal. There are also cases of mutations or birth abnormalities in animals (including humans) which have resulted in three legs.
Tripedalism in mythology, folklore and fiction
Although largely absent from biology, three-legged creatures feature in the mytho
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https://en.wikipedia.org/wiki/Sambucus%20canadensis
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Sambucus canadensis, the American black elderberry, Canada elderberry, or common elderberry, is a species of elderberry native to a large area of North America east of the Rocky Mountains, south to Bolivia. It grows in a variety of conditions including both wet and dry soils, primarily in sunny locations.
Description
It is a deciduous suckering shrub growing to tall. The leaves are arranged in opposite pairs, pinnate with five to nine leaflets, the leaflets around long and 5 cm broad. In summer, it bears large ( diameter) corymbs of white flowers above the foliage, the individual flowers diameter, with five petals.
The fruit (known as an elderberry) is a dark purple to black berry 3–5 mm diameter, produced in drooping clusters in the fall.
Taxonomy
It is closely related to the European Sambucus nigra. Some authors treat it as conspecific, under the name Sambucus nigra subsp. canadensis.
Toxicity
Inedible parts of the plant, such as the leaves, stems, roots, seeds and unripe fruits, can be toxic at lethal doses due to the presence of cyanogenic glycosides and alkaloids. Traditional methods of consuming elderberry includes jams, jellies, and syrups, all of which cook down the fruit and strain out the seeds.
Unpublished research may show that S. canadensis (American elderberry) has lower cyanide levels than apple juice, and that its fruit does not contain enough beta-glucosidase (which convert glucosides into cyanide) to create cyanide within that biochemical pathway. For comparisons, assuming S. nigra has levels of no more than 25 micrograms of cyanogenic glycosides/milligram of berry weight, assuming all of the glycosides were converted to cyanide, and assuming a toxicity of 50 mg for a 50 kg vertebrate, one would need to eat 2 kilograms (~4.4 pounds) of berries in one sitting to reach the lower limits of lethal toxicity (1 mg cyanide/kg of weight). For the upper limits (3 mg/kg), one would need to eat 6 kg or ~13 pounds.
Uses
The flower, known as elderflo
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https://en.wikipedia.org/wiki/Near-threatened%20species
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A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature (IUCN) as that may be vulnerable to endangerment in the near future, but it does not currently qualify for the threatened status.
The IUCN notes the importance of re-evaluating near-threatened taxon at appropriate intervals.
The rationale used for near-threatened taxa usually includes the criteria of vulnerable which are plausible or nearly met, such as reduction in numbers or range. Near-threatened species evaluated from 2001 onwards may also be ones which are dependent on conservation efforts to prevent their becoming threatened, whereas before this conservation-dependent species were given a separate category ("Conservation Dependent").
Additionally, the 402 conservation-dependent taxa may also be considered near-threatened.
IUCN Categories and Criteria version 2.3
Before 2001, the IUCN used the version 2.3 Categories and Criteria to assign conservation status, which included a separate category for conservation-dependent species ("Conservation Dependent", LR/cd). With this category system, Near Threatened and Conservation Dependent were both subcategories of the category "Lower Risk". Taxa which were last evaluated before 2001 may retain their LR/cd or LR/nt status, although had the category been assigned with the same information today the species would be designated simply "Near Threatened (NT)" in either case.
Gallery
See also
IUCN Red List near threatened species, ordered by taxonomic rank.
:Category:IUCN Red List near threatened species, ordered alphabetically.
List of near threatened amphibians
List of near threatened arthropods
List of near threatened birds
List of near threatened fishes
List of near threatened insects
List of near threatened invertebrates
List of near threatened mammals
List of near threatened molluscs
List of near threatened reptiles
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https://en.wikipedia.org/wiki/Ascending%20cholangitis
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Ascending cholangitis, also known as acute cholangitis or simply cholangitis, is inflammation of the bile duct, usually caused by bacteria ascending from its junction with the duodenum (first part of the small intestine). It tends to occur if the bile duct is already partially obstructed by gallstones.
Cholangitis can be life-threatening, and is regarded as a medical emergency. Characteristic symptoms include yellow discoloration of the skin or whites of the eyes, fever, abdominal pain, and in severe cases, low blood pressure and confusion. Initial treatment is with intravenous fluids and antibiotics, but there is often an underlying problem (such as gallstones or narrowing in the bile duct) for which further tests and treatments may be necessary, usually in the form of endoscopy to relieve obstruction of the bile duct. The word is from Greek chol-, bile + ang-, vessel + -itis, inflammation.
Signs and symptoms
A person with cholangitis may complain of abdominal pain (particularly in the right upper quadrant of the abdomen), fever, rigors (uncontrollable shaking) and a feeling of uneasiness (malaise). Some may report jaundice (yellow discoloration of the skin and the whites of the eyes).
Physical examination findings typically include jaundice and right upper quadrant tenderness. Charcot's triad is a set of three common findings in cholangitis: abdominal pain, jaundice, and fever. This was assumed in the past to be present in 50–70% of cases, although more recently the frequency has been reported as 15–20%. Reynolds' pentad includes the findings of Charcot's triad with the presence of septic shock and mental confusion. This combination of symptoms indicates worsening of the condition and the development of sepsis, and is seen less commonly still.
In the elderly, the presentation may be atypical; they may directly collapse due to sepsis without first showing typical features. Those with an indwelling stent in the bile duct (see below) may not develop jaundice.
C
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https://en.wikipedia.org/wiki/Ingress%20router
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An ingress router is a label switch router that is a starting point (source) for a given label-switched path (LSP). An ingress router may be an egress router or an intermediate router for any other LSP(s). Hence the role of ingress and egress routers is LSP specific. Usually, the MPLS label is attached with an IP packet at the ingress router and removed at the egress router, whereas label swapping is performed on the intermediate routers. However, in special cases (such as LSP Hierarchy in RFC 4206, LSP Stitching and MPLS local protection) the ingress router could be pushing label in label stack of an already existing MPLS packet (instead of an IP packet). Note that, although the ingress router is the starting point of an LSP, it may or may not be the source of the under-lying IP packets.
MPLS networking
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https://en.wikipedia.org/wiki/Florentine%20flask
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A florentine flask, also known as florentine receiver, florentine separator or essencier (from the French), other shapes called florentine vase or florentine vessel, is an oil–water separator fed with condensed vapors of a steam distillation in a fragrance extraction process.
Description
When the raw material is heated with steam from boiling water, volatile fragrant compounds and steam leave the still. The vapours are cooled in the condenser and become liquid. The liquid runs into the florentine receiver where the water and essential oil phases separate.
The essential oils phase separates from water because the oils have a different density than water, and are not water-soluble.
There are two main types of florentines in use. One separates essential oils of lower density than water, for example lavender oil, accumulating in a layer floating on the water. This kind of florentine has to be airtight to reduce the loss of volatile substances. The other type is intended for oils that are denser than water, where the oil accumulates beneath the water phase, for instance cinnamon, wintergreen, vetiver, patchouli or cloves. The floating water phase avoids the loss of volatile compounds from the oil. There are also florentines that are able to accommodate oils that are denser or less dense than water.
The separated water is a herbal distillate and can be fed back into the still or may in some cases be sold as herbal water. Because small droplets of oil are entrained with the water flowing out of the florentine, the yield can sometimes be increased by using more than one florentine in series.
For laboratory use, a small glass florentine without a base is called a florentine vase, as it has a slight resemblance to a small amphora. Larger glass receivers with base are called florentine flasks or essenciers.
Glass is normally only used up to 15 liter vessels; above this size, glass is too fragile, so that metal is used for larger capacities.
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https://en.wikipedia.org/wiki/OSSIM
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OSSIM (Open Source Security Information Management) is an open source security information and event management system, integrating a selection of tools designed to aid network administrators in computer security, intrusion detection and prevention.
The project began in 2003 as a collaboration between Dominique Karg, Julio Casal and later Alberto Román. In 2008 it became the basis for their company AlienVault. Following the acquisition of the Eureka project label and completion of R&D, AlienVault began selling a commercial derivative of OSSIM ('AlienVault Unified Security Management'). AlienVault was acquired by AT&T Communications and renamed AT&T Cybersecurity in 2019.
OSSIM has had four major-version releases since its creation and is on a 5.x.x version numbering. An information visualization of the contributions to the source code for OSSIM was published at 8 years of OSSIM. The project has approximately 7.4 million lines of code. The current version of OSSIM is 5.7.5 and was released on September 16, 2019. Information about this release and past versions can be found here
As a SIEM system, OSSIM is intended to give security analysts and administrators a more complete view of all the security-related aspects of their system, by combining log management which can be extended with plugins and asset management and discovery with information from dedicated information security controls and detection systems. This information is then correlated together to create contexts to the information not visible from one piece alone. Alarm and availability views along with reporting capabilities are provided to enhance the capabilities of the tool and its utility to the security and systems engineers.
OSSIM performs these functions using other well-known open-source software security components, unifying them under a single browser-based user interface. The interface provides graphical analysis tools for information collected from the underlying open source software compo
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https://en.wikipedia.org/wiki/Recombinase
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Recombinases are genetic recombination enzymes.
Site specific recombinases
DNA recombinases are widely used in multicellular organisms to manipulate the structure of genomes, and to control gene expression. These enzymes, derived from bacteria (bacteriophages) and fungi, catalyze directionally sensitive DNA exchange reactions between short (30–40 nucleotides) target site sequences that are specific to each recombinase. These reactions enable four basic functional modules: excision/insertion, inversion, translocation and cassette exchange, which have been used individually or combined in a wide range of configurations to control gene expression.
Types include:
Cre recombinase
Hin recombinase
Tre recombinase
FLP recombinase
Homologous recombination
Recombinases have a central role in homologous recombination in a wide range of organisms. Such recombinases have been described in archaea, bacteria, eukaryotes and viruses.
Archaea
The archaeon Sulfolobus solfataricus RadA recombinase catalyzes DNA pairing and strand exchange, central steps in recombinational repair. The RadA recombinase has greater similarity to the eukaryotic Rad51 recombinase than to the bacterial RecA recombinase.
Bacteria
RecA recombinase appears to be universally present in bacteria. RecA has multiple functions, all related to DNA repair. RecA has a central role in the repair of replication forks stalled by DNA damage and in the bacterial sexual process of natural genetic transformation.
Eukaryotes
Eukaryotic Rad51 and its related family members are homologous to the archaeal RadA and bacterial RecA recombinases. Rad51 is highly conserved from yeast to humans. It has a key function in the recombinational repair of DNA damages, particularly double-strand damages such as double-strand breaks. In humans, over- or under-expression of Rad51 occurs in a wide variety of cancers.
During meiosis Rad51 interacts with another recombinase, Dmc1, to form a presynaptic filament that is
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https://en.wikipedia.org/wiki/ASMO%20449
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ASMO 449 is a, now technologically obsolete, 7-bit coded character set to encode the Arabic language.
History
This character set was devised by the now extinct Arab Standardization and Metrology Organization in 1982 to be the 7-bit standard to be used in Arabic-speaking countries. The design of this character set is derived from the 7-bit ISO 646 (version of 1973) but with modifications suited for the Arabic language. In code points ranging from 0x41 to 0x72 (hexadecimal), Latin letters were replaced with Arabic letters. Punctuation marks which were identical in the Latin and Arabic scripts remained the same, but where they differed (comma, semicolon, question mark), the Latin ones were replaced by Arabic ones. Only nominal letters are encoded, no preshaped forms of the letters, so shaping processing is required for display. This character set is not bidirectional and was intended to be used in right to left writing. Therefore, symmetrical punctuation marks ("(", ")", "<", ">", "[", "]", "{" and "}") appears as reversed (")", "(", ">", "<", "]", "[", "}" and "{").
ASMO 449 was registered in the International Register of Coded Character Sets as IR 089 in 1985 and approved as an ISO standard as ISO 9036:1987 Information processing - Arabic 7-bit coded character set for information interchange.
Character set
There is a variant, sometimes named ASMO 449+ which adds the characters NBSP in 0x75, "ﹳ" in 0x76, "لآ" in 0x77, "لأ" in 0x78, "لإ" in 0x79 and "لا" in 0x7A.
Relationship with other character sets
ASMO 449 is a 7-bit character set. Although some encodings allocate this 7-bit character set in the upper part of the 8-bit character set, it should not be confused with ASMO 708. In the character sets that allocate ASMO 449 (or some variant of it) in the upper part of the 8-bit character set, the existence of apparently repeated characters is due to the fact that the characters in the lower part are for left-to-right script while the characters in the upper part are
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https://en.wikipedia.org/wiki/Christian%20Topography
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The Christian Topography (, ) is a 6th-century work, one of the earliest essays in scientific geography written by a Christian author. It originally consisted of five books written by Cosmas Indicopleustes and expanded to ten and eventually to twelve books at around 550 AD.
Cosmology
Cosmas Indicopleustes, the author of the Christian Topography, put forward the idea that the world is flat. Originally written in Greek with illustrations and maps, his view of the flatness of the world may have been influenced by some Jewish and Eastern contemporaries. While most of the Christians of the same period maintained that the Earth was a sphere, the work advances the idea that the world is flat, and that the heavens form the shape of a box with a curved lid, and especially attacks the idea that the heavens were spherical and in motion, now known as the geocentric model of the universe. The author cites passages of scripture which he interprets originally in order to support his thesis, and attempts to argue down the idea of a spherical earth by stigmatizing it as "pagan". An early surviving reference to the work is by Patriarch Photios I of Constantinople in the 9th century AD. Photius condemns the style and syntax of the text as well as the honesty of the author. More recent authors tend to agree with Photius on the stylistic points, but to find the work generally reliable for geographical and historical references. Edward Gibbon, for example, said "the nonsense of the Monk was, nevertheless, mingled with the practical knowledge of the traveller" and used it in writing The History of the Decline and Fall of the Roman Empire.
The Topography is often erroneously cited as evidence that Christianity introduced the idea of the flat-earth into the world, and brought in the age of ignorance. The latter pages of his work are devoted to rebutting the criticism of his fellow monks. He repeatedly denounces "those reprobate Christians who, ..., prefer, through their perverse f
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https://en.wikipedia.org/wiki/Prony%27s%20method
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Prony analysis (Prony's method) was developed by Gaspard Riche de Prony in 1795. However, practical use of the method awaited the digital computer. Similar to the Fourier transform, Prony's method extracts valuable information from a uniformly sampled signal and builds a series of damped complex exponentials or damped sinusoids. This allows the estimation of frequency, amplitude, phase and damping components of a signal.
The method
Let be a signal consisting of evenly spaced samples. Prony's method fits a function
to the observed . After some manipulation utilizing Euler's formula, the following result is obtained, which allows more direct computation of terms:
where
are the eigenvalues of the system,
are the damping components,
are the angular-frequency components,
are the phase components,
are the amplitude components of the series,
is the imaginary unit ().
Representations
Prony's method is essentially a decomposition of a signal with complex exponentials via the following process:
Regularly sample so that the -th of samples may be written as
If happens to consist of damped sinusoids, then there will be pairs of complex exponentials such that
where
Because the summation of complex exponentials is the homogeneous solution to a linear difference equation, the following difference equation will exist:
The key to Prony's Method is that the coefficients in the difference equation are related to the following polynomial:
These facts lead to the following three steps within Prony's method:
1) Construct and solve the matrix equation for the values:
Note that if , a generalized matrix inverse may be needed to find the values .
2) After finding the values, find the roots (numerically if necessary) of the polynomial
The -th root of this polynomial will be equal to .
3) With the values, the values are part of a system of linear equations that may be used to solve for the values:
where unique values are used. It is possible to
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https://en.wikipedia.org/wiki/Coloured%20Book%20protocols
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The Coloured Book protocols were a set of communication protocols for computer networks developed in the United Kingdom in the 1970s. These protocols were designed to enable communication and data exchange between different computer systems and networks. The name originated with each protocol being identified by the colour of the cover of its specification document. The protocols were in use until the 1990s when the Internet protocol suite came into widespread use.
History
In the mid-1970s, the British Post Office Telecommunications division (BPO-T) worked with the academic community in the United Kingdom and the computer industry to develop a set of standards to enable interoperability among different computer systems based on the X.25 protocol suite for packet-switched wide area network (WAN) communication. First defined in 1975, the standards evolved through experience developing protocols for the NPL network in the late 1960s and the Experimental Packet Switched Service in the early 1970s.
The Coloured Book protocols were used on SERCnet from 1980, and SWUCN from 1982, both of which became part of the JANET academic network from 1984. The protocols were influential in the development of computer networks, particularly in the UK, gained some acceptance internationally as the first complete X.25 standard, and gave the UK "several years lead over other countries".
From late 1991, Internet protocols were adopted on the Janet network instead; they were operated simultaneously for a while, until X.25 support was phased out entirely in August 1997.
Protocols
The standards were defined in several documents, each addressing different aspects of computer network communication. They were identified by the colour of the cover:
Pink Book
The Pink Book defined protocols for transport over Ethernet. The protocol was basically X.25 level 3 running over LLC2.
Orange Book
The Orange Book defined protocols for transport over local networks using the Cambridge Ring (computer
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https://en.wikipedia.org/wiki/Vacuum%20deposition
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Vacuum deposition is a group of processes used to deposit layers of material atom-by-atom or molecule-by-molecule on a solid surface. These processes operate at pressures well below atmospheric pressure (i.e., vacuum). The deposited layers can range from a thickness of one atom up to millimeters, forming freestanding structures. Multiple layers of different materials can be used, for example to form optical coatings. The process can be qualified based on the vapor source; physical vapor deposition uses a liquid or solid source and chemical vapor deposition uses a chemical vapor.
Description
The vacuum environment may serve one or more purposes:
reducing the particle density so that the mean free path for collision is long
reducing the particle density of undesirable atoms and molecules (contaminants)
providing a low pressure plasma environment
providing a means for controlling gas and vapor composition
providing a means for mass flow control into the processing chamber.
Condensing particles can be generated in various ways:
thermal evaporation
sputtering
cathodic arc vaporization
laser ablation
decomposition of a chemical vapor precursor, chemical vapor deposition
In reactive deposition, the depositing material reacts either with a component of the gaseous environment (Ti + N → TiN) or with a co-depositing species (Ti + C → TiC). A plasma environment aids in activating gaseous species (N2 → 2N) and in decomposition of chemical vapor precursors (SiH4 → Si + 4H). The plasma may also be used to provide ions for vaporization by sputtering or for bombardment of the substrate for sputter cleaning and for bombardment of the depositing material to densify the structure and tailor properties (ion plating).
Types
When the vapor source is a liquid or solid the process is called physical vapor deposition (PVD). When the source is a chemical vapor precursor, the process is called chemical vapor deposition (CVD). The latter has several variants: low-pressure chemi
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https://en.wikipedia.org/wiki/Mode%20of%20action
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In pharmacology and biochemistry, mode of action (MoA) describes a functional or anatomical change, resulting from the exposure of a living organism to a substance. In comparison, a mechanism of action (MOA) describes such changes at the molecular level.
A mode of action is important in classifying chemicals, as it represents an intermediate level of complexity in between molecular mechanisms and physiological outcomes, especially when the exact molecular target has not yet been elucidated or is subject to debate. A mechanism of action of a chemical could be "binding to DNA" while its broader mode of action would be "transcriptional regulation". However, there is no clear consensus and the term mode of action is also often used, especially in the study of pesticides, to describe molecular mechanisms such as action on specific nuclear receptors or enzymes.
See also
Mechanism of action in pharmaceuticals
Adverse outcome pathway
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https://en.wikipedia.org/wiki/Coding%20best%20practices
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Coding best practices or programming best practices are a set of informal rules (best practices) that many software developers in computer programming follow to improve software quality.
Many computer programs remain in use for long periods of time, so any rules need to facilitate both initial development and subsequent maintenance and enhancement of source code by people other than the original authors.
In the ninety-ninety rule, Tom Cargill is credited with an explanation as to why programming projects often run late: "The first 90% of the code accounts for the first 90% of the development time. The remaining 10% of the code accounts for the other 90% of the development time." Any guidance which can redress this lack of foresight is worth considering.
The size of a project or program has a significant effect on error rates, programmer productivity, and the amount of management needed.
Software quality
As listed below, there are many attributes associated with good software. Some of these can be mutually contradictory (e.g. being very fast versus performing extensive error checking), and different customers and participants may have different priorities. Weinberg provides an example of how different goals can have a dramatic effect on both effort required and efficiency. Furthermore, he notes that programmers will generally aim to achieve any explicit goals which may be set, probably at the expense of any other quality attributes.
Sommerville has identified four generalized attributes which are not concerned with what a program does, but how well the program does it:
Maintainability
Dependability
Efficiency
Usability
Weinberg has identified four targets which a good program should meet:
Does a program meet its specification ("correct output for each possible input")?
Is the program produced on schedule (and within budget)?
How adaptable is the program to cope with changing requirements?
Is the program efficient enough for the environment in which i
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https://en.wikipedia.org/wiki/Figure%20of%20merit
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A figure of merit (FOM) is a performance metric that characterizes the performance of a device, system, or method, relative to its alternatives.
Examples
Accuracy of a rifle
Audio amplifier figures of merit such as gain or efficiency
Battery life of a laptop computer
Calories per serving
Clock rate of a CPU is often given as a figure of merit, but is of limited use in comparing between different architectures. FLOPS may be a better figure, though these too aren't completely representative of the performance of a CPU.
Contrast ratio of an LCD
Frequency response of a speaker
Fill factor of a solar cell
Resolution of the image sensor in a digital camera
Measure of the detection performance of a sonar system, defined as the propagation loss for which a 50% detection probability is achieved
Noise figure of a radio receiver
The thermoelectric figure of merit, zT, a material constant proportional to the efficiency of a thermoelectric couple made with the material
The figure of merit of digital-to-analog converter, calculated as (power dissipation)/(2ENOB × effective bandwidth) [J/Hz]
Luminous efficacy of lighting
Profit of a company
Residual noise remaining after compensation in an aeromagnetic survey
Heat absorption and transfer quality for a solar cooker
Computational benchmarks are synthetic figures of merit that summarize the speed of algorithms or computers in performing various typical tasks.
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https://en.wikipedia.org/wiki/Unlicensed%20Personal%20Communications%20Services
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Unlicensed Personal Communications Services or UPCS band is the 1920–1930 MHz frequency band allocated by the United States Federal Communications Commission (FCC) for short range Personal Communications Services (PCS) applications in the United States, such as the Digital Enhanced Cordless Telecommunications (DECT) wireless protocol.
History
Prior to an FCC rules change in April 2005, the band also included the frequencies 1910-1920 MHz and 2390–2400 MHz. These were used for a variety of short range communications, including point-to-point microwave links.
Allocation
These allocation rules are described in Title 47, Part 15 of the Code of Federal Regulations.
Licensed PCS, although not necessarily distinguished as such from UPCS, is used for digital mobile phone services.
DECT devices designed to operate in this band in the US use the marketing term DECT 6.0.
See also
Amateur radio (Licence Required)
Citizens band radio
Family Radio Service
General Mobile Radio Service
Multi-Use Radio Service
Bandplans
Telephone services
Consumer electronics
Radio technology
Radio regulations
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https://en.wikipedia.org/wiki/Carlos%20J.%20Finlay%20Prize%20for%20Microbiology
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The Carlos J. Finlay Prize is a biennial scientific prize sponsored by the Government of Cuba and awarded since 1980 by the United Nations Educational, Scientific and Cultural Organization (UNESCO) to people or organizations for their outstanding contributions to microbiology (including immunology, molecular biology, genetics, etc.) and its applications. Winners receive a grant of $5,000 USD donated by the Government of Cuba and an Albert Einstein Silver Medal from UNESCO.
The Prize is awarded in odd years (to coincide with UNESCO's General Conference) and is named after Carlos Juan Finlay (1833 – 1915), a Cuban physician and microbiologist widely known for his pioneering discoveries in the field of yellow fever.
Winners
Source: UNESCO
1980 - Roger Y. Stanier (Canada)
1983 - César Milstein, FRS (Argentina, United Kingdom)
1985 - Victor Nussenzweig and Ruth Nussenzweig (Brazil)
1987 - Hélio Gelli Pereira (Brazil) and Peter Reichard (Sweden)
1989 - Georges Cohen (France) and Walter Fiers (Belgium)
1991 - Margarita Salas and Eladio Viñuela (Spain) and Jean-Marie Ghuysen (Belgium)
1993 - International Society of Soil Science, James Michael Lynch (UK), James Tiedje (USA), Johannes Antonie Van Veen (Netherlands)
1995 - Jan Balzarini (Belgium) and Pascale Cossart (France)
1996 - Etienne Pays (Belgium) and Sheikh Riazzudin (Pakistan)
1999 - Ádám Kondorosi (Hungary)
2001 - Susana López Charreton and Carlos Arias Ortiz (Mexico)
2003 - Antonio Peña Díaz (Mexico)
2005 - Khatijah Binti Mohamad Yusoff (Malaysia)
2015 - Yoshihiro Kawaoka (Japan)
2017 - Samir Kumar Saha (Bangladesh) and Shahida Hasnain (Pakistan)
2020 - Kenya Honda (Japan)
See also
List of biology awards
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https://en.wikipedia.org/wiki/Pixel%20aspect%20ratio
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A Pixel aspect ratio (often abbreviated PAR) is a mathematical ratio that describes how the width of a pixel in a digital image compared to the height of that pixel.
Most digital imaging systems display an image as a grid of tiny, square pixels. However, some imaging systems, especially those that must be compatible with standard-definition television motion pictures, display an image as a grid of rectangular pixels, in which the pixel width and height are different. Pixel aspect ratio describes this difference.
Use of pixel aspect ratio mostly involves pictures pertaining to standard-definition television and some other exceptional cases. Most other imaging systems, including those that comply with SMPTE standards and practices, use square pixels.
PAR is also known as sample aspect ratio and abbreviated SAR, though it can be confused with storage aspect ratio.
Introduction
The ratio of the width to the height of an image is known as the aspect ratio, or more precisely the display aspect ratio (DAR) – the aspect ratio of the image as displayed; for TV, DAR was traditionally 4:3 (a.k.a. fullscreen), with 16:9 (a.k.a. widescreen) now the standard for HDTV. In digital images, there is a distinction with the storage aspect ratio (SAR), which is the ratio of pixel dimensions. If an image is displayed with square pixels, then these ratios agree; if not, then non-square, "rectangular" pixels are used, and these ratios disagree. The aspect ratio of the pixels themselves is known as the pixel aspect ratio (PAR) – for square pixels this is 1:1 – and these are related by the identity:
{| class="wikitable"
|-
| SAR × PAR = DAR
|}
Rearranging (solving for PAR) yields:
{| class="wikitable"
|-
| PAR = DAR / SAR
|}
For example:
A 640 × 480 VGA image has a SAR of 640/480 = 4:3, and if displayed on a 4:3 display (DAR = 4:3) has square pixels, hence a PAR of 1:1.
By contrast, a 720 × 576 D-1 PAL image has a SAR of 720/576 = 5:4, but if displayed on a 4:3 display (DAR = 4:3)
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