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https://en.wikipedia.org/wiki/Medial%20condyle%20of%20femur
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The medial condyle is one of the two projections on the lower extremity of femur, the other being the lateral condyle.
The medial condyle is larger than the lateral (outer) condyle due to more weight bearing caused by the centre of mass being medial to the knee. On the posterior surface of the condyle the linea aspera (a ridge with two lips: medial and lateral; running down the posterior shaft of the femur) turns into the medial and lateral supracondylar ridges, respectively. The outermost protrusion on the medial surface of the medial condyle is referred to as the "medial epicondyle" and can be palpated by running fingers medially from the patella with the knee in flexion.
It is important to take into consideration the difference in the length of the condyles in a cross section to better understand the geometry of the knee. The medial femoral condyle has an extra segment which is the cause for the passive rotation of the knee joint.
Additional images
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https://en.wikipedia.org/wiki/Lateral%20condyle%20of%20femur
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The lateral condyle is one of the two projections on the lower extremity of the femur. The other one is the medial condyle. The lateral condyle is the more prominent and is broader both in its front-to-back and transverse diameters.
Clinical significance
The most common injury to the lateral femoral condyle is an osteochondral fracture combined with a patellar dislocation. The osteochondral fracture occurs on the weight-bearing portion of the lateral condyle. Typically, the condyle will fracture (and the patella may dislocate) as a result of severe impaction from activities such as downhill skiing and parachuting.
Open reduction and internal fixation surgery is typically used to repair an osteochondral fracture. For a Type B1 partial articular fracture of the lateral condyle, interfragmentary lag screws are used to secure the bone back together. Supplementation of buttress screws or a buttress plate is used if the fracture extends to the proximal metaphysis or distal diaphysis.
Additional images
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https://en.wikipedia.org/wiki/Long%20plantar%20ligament
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The long plantar ligament (long calcaneocuboid ligament; superficial long plantar ligament) is a long ligament on the underside of the foot that connects the calcaneus with the 2nd to 5th metatarsal.
Structure
The long plantar ligament is the longest of all the ligaments of the tarsus. It is attached behind to the plantar surface of the calcaneus in front of the tuberosity, and in front to the tuberosity on the plantar surface of the cuboid bone, the more superficial fibers being continued forward to the bases of the second, third, and fourth metatarsal bones.
This ligament converts the groove on the plantar surface of the cuboid into a canal for the tendon of the fibularis longus.
Deep to this ligament is the short plantar ligament.
The long plantar ligament separates the two heads of the quadratus plantae muscle.
See also
Plantar calcaneonavicular ligament
Short plantar ligament
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https://en.wikipedia.org/wiki/Fibular%20retinacula
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The fibular retinacula (also known as peroneal retinacula) are fibrous retaining bands that bind down the tendons of the fibularis longus and fibularis brevis muscles as they run across the side of the ankle. (Retinaculum is Latin for "retainer.")
These bands consist of the superior fibular retinaculum and the inferior fibular retinaculum. The superior fibers are attached above to the lateral malleolus and below to the lateral surface of the calcaneus. The inferior fibers are continuous in front with those of the inferior extensor retinaculum of the foot; behind they are attached to the lateral surface of the calcaneus; some of the fibers are fixed to the calcaneal tubercle, forming a septum between the tendons of the fibularis longus and fibularis brevis.
See also
Fibularis longus
Fibularis brevis
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https://en.wikipedia.org/wiki/Parametric%20oscillator
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A parametric oscillator is a driven harmonic oscillator in which the oscillations are driven by varying some parameters of the system at some frequencies, typically different from the natural frequency of the oscillator. A simple example of a parametric oscillator is a child pumping a playground swing by periodically standing and squatting to increase the size of the swing's oscillations. The child's motions vary the moment of inertia of the swing as a pendulum. The "pump" motions of the child must be at twice the frequency of the swing's oscillations. Examples of parameters that may be varied are the oscillator's resonance frequency and damping .
Parametric oscillators are used in several areas of physics. The classical varactor parametric oscillator consists of a semiconductor varactor diode connected to a resonant circuit or cavity resonator. It is driven by varying the diode's capacitance by applying a varying bias voltage. The circuit that varies the diode's capacitance is called the "pump" or "driver". In microwave electronics, waveguide/YAG-based parametric oscillators operate in the same fashion. Another important example is the optical parametric oscillator, which converts an input laser light wave into two output waves of lower frequency ().
When operated at pump levels below oscillation, the parametric oscillator can amplify a signal, forming a parametric amplifier (paramp). Varactor parametric amplifiers were developed as low-noise amplifiers in the radio and microwave frequency range. The advantage of a parametric amplifier is that it has much lower noise than an amplifier based on a gain device like a transistor or vacuum tube. This is because in the parametric amplifier a reactance is varied instead of a (noise-producing) resistance. They are used in very low noise radio receivers in radio telescopes and spacecraft communication antennas.
Parametric resonance occurs in a mechanical system when a system is parametrically excited and oscillates at o
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https://en.wikipedia.org/wiki/Fibular%20collateral%20ligament
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The lateral collateral ligament (LCL, long external lateral ligament or fibular collateral ligament) is an extrinsic ligament of the knee located on the lateral side of the knee. Its superior attachment is at the lateral epicondyle of the femur (superoposterior to the popliteal groove); its inferior attachment is at the lateral aspect of the head of fibula (anterior to the apex). The LCL is not fused with the joint capsule. Inferiorly, the LCL splits the tendon of insertion of the biceps femoris muscle.
Structure
The LCL measures some 5 cm in length. It is rounded, and is more narrow and less broad compared to the medial collateral ligament. It extends obliquely inferoposteriorly from its superior attachment to its inferior attachment.
In contrast to the medial collateral ligament, it is not fused with either the capsular ligament nor the lateral meniscus. Because of this, the LCL is more flexible than its medial counterpart, and is therefore less susceptible to injury.
Relations
Immediately below its origin is the groove for the tendon of the popliteus.
The greater part of its lateral surface is covered by the tendon of the biceps femoris; the tendon, however, divides at its insertion into two parts, which are separated by the ligament.
Deep to the ligament are the tendon of the popliteus, and the inferior lateral genicular vessels and nerve.
Function
Both collateral ligaments are taut when the knee joint is in extension. With the knee in flexion, the radius of curvatures of the condyles is decreased and the origin and insertions of the ligaments are brought closer together which make them lax. The pair of ligaments thus stabilize the knee joint in the coronal plane. Therefore, damage and rupture of these ligaments can be diagnosed by examining the knee's stability in the mediolateral axis.
Clinical significance
Causes of injury
The LCL is usually injured as a result of varus force across the knee, which is a force pushing the knee from the medial (inn
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https://en.wikipedia.org/wiki/Flora%20of%20North%20America
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The Flora of North America North of Mexico (usually referred to as FNA) is a multivolume work describing the native plants and naturalized plants of North America, including the United States, Canada, St. Pierre and Miquelon, and Greenland. It includes bryophytes and vascular plants. All taxa are described and included in dichotomous keys, distributions of all species and infraspecific taxa are mapped, and about 20% of species are illustrated with line drawings prepared specifically for FNA. It is expected to fill 30 volumes when completed and will be the first work to treat all of the known flora north of Mexico; in 2015 it was expected that the series would conclude in 2017. Twenty-nine of the volumes have been published as of 2022.
Soon after publication, the contents are made available online.
FNA is a collaboration of about 1,000 authors, artists, reviewers, and editors from throughout the world.
Reception
The series has been praised for "the comprehensive treatments [that] allow botanists to examine taxonomic and geographical traits of genera across the North American continent, rather than being limited by keys developed for one's own state or region".
Reviewing volume 3, Paula Wolfe found the series worth recommending, and praised it for high standards.
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https://en.wikipedia.org/wiki/Lateral%20supracondylar%20ridge
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The lateral supracondylar ridge is a prominent, rough margin on the lower part of the lateral border of the humerus. It presents an anterior lip for the origin of forearm extensors, including the brachioradialis muscle above, and the extensor carpi radialis longus muscle below. It also presents a posterior lip for the triceps brachii, and an intermediate ridge for the attachment of the lateral intermuscular septum.
Clinical significance
The lateral supracondylar ridge may be broken in a supracondylar humerus fracture, common in children.
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https://en.wikipedia.org/wiki/Permeation
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In physics and engineering, permeation (also called imbuing) is the penetration of a permeate (a fluid such as a liquid, gas, or vapor) through a solid. It is directly related to the concentration gradient of the permeate, a material's intrinsic permeability, and the materials' mass diffusivity. Permeation is modeled by equations such as Fick's laws of diffusion, and can be measured using tools such as a minipermeameter.
Description
The process of permeation involves the diffusion of molecules, called the permeant, through a membrane or interface. Permeation works through diffusion; the permeant will move from high concentration to low concentration across the interface. A material can be semipermeable, with the presence of a semipermeable membrane. Only molecules or ions with certain properties will be able to diffuse across such a membrane. This is a very important mechanism in biology where fluids inside a blood vessel need to be regulated and controlled. Permeation can occur through most materials including metals, ceramics and polymers. However, the permeability of metals is much lower than that of ceramics and polymers due to their crystal structure and porosity.
Permeation is something that must be considered carefully in many polymer applications, due to their high permeability. Permeability depends on the temperature of the interaction as well as the characteristics of both the polymer and the permeant component. Through the process of sorption, molecules of the permeant can be either absorbed or desorbed at the interface. The permeation of a material can be measured through numerous methods that quantify the permeability of a substance through a specific material.
Permeability due to diffusion is measured in SI units of mol/(m･s･Pa) although Barrers are also commonly used. Permeability due to diffusion is not to be confused with Permeability (earth sciences) due to fluid flow in porous solids measured in Darcy.
Related terms
Permeant: The substanc
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https://en.wikipedia.org/wiki/List%20of%20triangle%20inequalities
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In geometry, triangle inequalities are inequalities involving the parameters of triangles, that hold for every triangle, or for every triangle meeting certain conditions. The inequalities give an ordering of two different values: they are of the form "less than", "less than or equal to", "greater than", or "greater than or equal to". The parameters in a triangle inequality can be the side lengths, the semiperimeter, the angle measures, the values of trigonometric functions of those angles, the area of the triangle, the medians of the sides, the altitudes, the lengths of the internal angle bisectors from each angle to the opposite side, the perpendicular bisectors of the sides, the distance from an arbitrary point to another point, the inradius, the exradii, the circumradius, and/or other quantities.
Unless otherwise specified, this article deals with triangles in the Euclidean plane.
Main parameters and notation
The parameters most commonly appearing in triangle inequalities are:
the side lengths a, b, and c;
the semiperimeter s = (a + b + c) / 2 (half the perimeter p);
the angle measures A, B, and C of the angles of the vertices opposite the respective sides a, b, and c (with the vertices denoted with the same symbols as their angle measures);
the values of trigonometric functions of the angles;
the area T of the triangle;
the medians ma, mb, and mc of the sides (each being the length of the line segment from the midpoint of the side to the opposite vertex);
the altitudes ha, hb, and hc (each being the length of a segment perpendicular to one side and reaching from that side (or possibly the extension of that side) to the opposite vertex);
the lengths of the internal angle bisectors ta, tb, and tc (each being a segment from a vertex to the opposite side and bisecting the vertex's angle);
the perpendicular bisectors pa, pb, and pc of the sides (each being the length of a segment perpendicular to one side at its midpoint and reaching to one of the other sides);
t
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https://en.wikipedia.org/wiki/Thomson%20%28unit%29
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The thomson (symbol: Th) is a unit that has appeared infrequently in scientific literature relating to the field of mass spectrometry as a unit of mass-to-charge ratio. The unit was proposed by Cooks and Rockwood naming it in honour of J. J. Thomson who measured the mass-to-charge ratio of electrons and ions.
Definition
The thomson is defined as
where Da is the symbol for the unit dalton (also called the unified atomic mass unit, symbol u), and e is the elementary charge which is the unit of electric charge in the system of Hartree atomic units.
For example, the ion C7H72+ has a mass of 91 Da. Its charge number is +2, and hence its charge is 2e. The ion will be observed at 45.5 Th in a mass spectrum.
The thomson allows for negative values for negatively charged ions. For example, the benzoate anion would be observed at −121 Th since the charge is −e.
Use
The thomson has been used by some mass spectrometrists, for example Alexander Makarov—the inventor of the Orbitrap—in a scientific poster, and a 2015 presentation. Other uses of the thomson include papers,
and (notably) one book. The journal Rapid Communications in Mass Spectrometry (in which the original article appeared) states that "the thomson (Th) may be used for such purposes as a unit of mass-to-charge ratio although it is not currently approved by IUPAP or IUPAC." Even so, the term has been called "controversial" by RCM's former Editor-in Chief (in a review the Hoffman text cited above). The book, Mass Spectrometry Desk Reference, argues against the use of the thomson. However, the editor-in-chief of the Journal of the Mass Spectrometry Society of Japan has written an editorial in support of the thomson unit.
The thomson is not an SI unit, nor has it been defined by IUPAC.
Since 2013, the thomson is deprecated by IUPAC (Definitions of Terms Relating to Mass Spectrometry). Since 2014, Rapid Communications in Mass Spectrometry regards the thomson as a "term that should be avoided in mass spectrometry p
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https://en.wikipedia.org/wiki/Geomagnetic%20latitude
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Geomagnetic latitude, or magnetic latitude (MLAT), is a parameter analogous to geographic latitude, except that, instead of being defined relative to the geographic poles, it is defined by the axis of the geomagnetic dipole, which can be accurately extracted from the International Geomagnetic Reference Field (IGRF).
See also
Earth's magnetic field
Geomagnetic equator
Ionosphere
L-shell
Magnetosphere
World Magnetic Model (WMM)
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https://en.wikipedia.org/wiki/Geocast
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Geocast refers to the delivery of information to a subset of destinations in a wireless peer-to-peer network identified by their geographical locations. It is used by some mobile ad hoc network routing protocols, but not applicable to Internet routing.
Geographic addressing
A geographic destination address is expressed in three ways: point, circle (with center point and radius), and polygon (a list of points, e.g., P(1), P(2), ..., P(n–1), P(n)). A geographic router (Geo Router) calculates its service area (geographic area it serves) as the union of the geographic areas covered by the networks attached to it. This service area is approximated by a single closed polygon. Geo Routers exchange service area polygons to build routing tables. The routers are organized in a hierarchy.
Applications
Geographic addressing and routing has many potential applications in geographic messaging, geographic advertising, delivery of geographically restricted services, and presence discovery of a service or mobile network participant in a limited geographic area (see Navas, Imieliński, 'GeoCast - Geographic Addressing and Routing'.)
See also
Abiding Geocast / Stored Geocast
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https://en.wikipedia.org/wiki/Lametasaurus
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Lametasaurus ( - meaning "Lameta lizard") named for the Lameta Formation, Jabalpur, India, is the generic name given to a possibly chimeric dinosaur species.
History of discovery
Between October 1917 and 1919 Charles Alfred Matley excavated fossils near Jabalpur. In 1921 he reported the find in the "Carnosaur Bed" of what he considered to be two megalosaurians, theropod dinosaurs. In 1923/1924 he named one of these as the type species Lametasaurus indicus. The generic name refers to the Lameta Formation, dating from the Maastrichtian, the specific name refers to India. However, Matley no longer identified it as a theropod but as a member of the Stegosauria instead, which concept at the time also included the armoured dinosaurs today assigned to the Ankylosauria; at first Matley had seen it as a stegosaurian in the modern sense and even intended to name it as a species of Omosaurus. The type specimen consisted of a number of dermal scutes, a sacrum of at least five sacral vertebrae, a pelvis, a tibia and teeth. In 1933 Matley and Friedrich von Huene described some more remains collected by Barnum Brown, thought to have been part of a tail club; later this was shown to be a large osteoderm.
However, in 1935 Dhirendra Kishore Chakravarti contested the interpretation as an armoured dinosaur. He claimed that the specimen was a chimera including titanosaurid armor, crocodile teeth and theropod hindlimb material. In 1964 Alick Walker chose the scutes as the lectotype, thus removing the teeth and the bones from the type material. The name Lametasaurus now designated the scutes only and was generally considered to represent a member of the Nodosauridae. The pelvis and hindlimb bones have in 2003 been suggested to belong to Rajasaurus, based on shared features in the . In 2008 Matthew Carrano e.a. discarded the possibility the scutes were ankylosaurian, stating they were probably titanosaurian, but noted that a comparison to the osteoderms of Ceratosaurus would help in dete
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https://en.wikipedia.org/wiki/Unrestricted%20grammar
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In automata theory, the class of unrestricted grammars (also called semi-Thue, type-0 or phrase structure grammars) is the most general class of grammars in the Chomsky hierarchy. No restrictions are made on the productions of an unrestricted grammar, other than each of their left-hand sides being non-empty. This grammar class can generate arbitrary recursively enumerable languages.
Formal definition
An unrestricted grammar is a formal grammar , where
is a finite set of nonterminal symbols,
is a finite set of terminal symbols with and disjoint,
is a finite set of production rules of the form where and are strings of symbols in and is not the empty string, and
is a specially designated start symbol.
As the name implies, there are no real restrictions on the types of production rules that unrestricted grammars can have.
Equivalence to Turing machines
The unrestricted grammars characterize the recursively enumerable languages. This is the same as saying that for every unrestricted grammar there exists some Turing machine capable of recognizing and vice versa. Given an unrestricted grammar, such a Turing machine is simple enough to construct, as a two-tape nondeterministic Turing machine. The first tape contains the input word to be tested, and the second tape is used by the machine to generate sentential forms from . The Turing machine then does the following:
Start at the left of the second tape and repeatedly choose to move right or select the current position on the tape.
Nondeterministically choose a production from the productions in .
If appears at some position on the second tape, replace by at that point, possibly shifting the symbols on the tape left or right depending on the relative lengths of and (e.g. if is longer than , shift the tape symbols left).
Compare the resulting sentential form on tape 2 to the word on tape 1. If they match, then the Turing machine accepts the word. If they don't, the Turing machine w
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https://en.wikipedia.org/wiki/Depression%20%28physiology%29
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In physiology and medicine, depression refers to a lowering, in particular a reduction in a specific biological variable or the functions of an organ. It is the opposite of elevation. For example, it is possible to refer to "depressed thyroid function" or to a depression of blood flow in a particular area.
Further examples:
Depression of the central nervous system of an animal may be expressed as drowsiness or sleep, lack of coordination and unconsciousness.
Respiratory depression or hypoventilation.
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https://en.wikipedia.org/wiki/History%20of%20mass%20spectrometry
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The history of mass spectrometry has its roots in physical and chemical studies regarding the nature of matter. The study of gas discharges in the mid 19th century led to the discovery of anode and cathode rays, which turned out to be positive ions and electrons. Improved capabilities in the separation of these positive ions enabled the discovery of stable isotopes of the elements. The first such discovery was with the element neon, which was shown by mass spectrometry to have at least two stable isotopes: 20Ne (neon with 10 protons and 10 neutrons) and 22Ne (neon with 10 protons and 12 neutrons). Mass spectrometers were used in the Manhattan Project for the separation of isotopes of uranium necessary to create the atomic bomb.
Prout's Hypothesis
Prout's hypothesis was an early 19th-century attempt to explain the properties of the chemical elements using the internal structure of the atom. In 1815, the English chemist William Prout observed that the atomic weights that had been measured were integer multiples of the atomic weight of hydrogen. Prout's hypothesis remained influential in chemistry throughout the 1820s. However, more careful measurements of the atomic weights, such as those compiled by Jöns Jakob Berzelius in 1828 or Edward Turner in 1832, appeared to disprove it. In particular the atomic weight of chlorine, which is 35.45 times that of hydrogen, could not at the time be explained in terms of Prout's hypothesis. It would take the better part of a century for this problem to be resolved.
Canal rays
In the mid-nineteenth century, Julius Plücker investigated the light emitted in discharge tubes and the influence of magnetic fields on the glow. Later, in 1869, Johann Wilhelm Hittorf studied discharge tubes with energy rays extending from a negative electrode, the cathode. These rays produced a fluorescence when they hit a tube's glass walls, and when interrupted by a solid object they cast a shadow.
Canal rays, also called anode rays, were observed by
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https://en.wikipedia.org/wiki/Hyper-encryption
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Hyper-encryption is a form of encryption invented by Michael O. Rabin which uses a high-bandwidth source of public random bits, together with a secret key that is shared by only the sender and recipient(s) of the message. It uses the assumptions of Ueli Maurer's bounded-storage model as the basis of its secrecy. Although everyone can see the data, decryption by adversaries without the secret key is still not feasible, because of the space limitations of storing enough data to mount an attack against the system.
Unlike almost all other cryptosystems except the one-time pad, hyper-encryption can be proved to be information-theoretically secure, provided the storage bound cannot be surpassed. Moreover, if the necessary public information cannot be stored at the time of transmission, the plaintext can be shown to be impossible to recover, regardless of the computational capacity available to an adversary in the future, even if they have access to the secret key at that future time.
A highly energy-efficient implementation of a hyper-encryption chip was demonstrated by Krishna Palem et al. using the Probabilistic CMOS or PCMOS technology and was shown to be ~205 times more efficient in terms of Energy-Performance-Product.
See also
Perfect forward secrecy
Randomness extractor
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https://en.wikipedia.org/wiki/GRASP%20%28object-oriented%20design%29
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General Responsibility Assignment Software Patterns (or Principles), abbreviated GRASP, is a set of "nine fundamental principles in object design and responsibility assignment" first published by Craig Larman in his 1997 book Applying UML and Patterns.
The different patterns and principles used in GRASP are controller, creator, indirection, information expert, low coupling, high cohesion, polymorphism, protected variations, and pure fabrication. All these patterns solve some software problems common to many software development projects. These techniques have not been invented to create new ways of working, but to better document and standardize old, tried-and-tested programming principles in object-oriented design.
Larman states that "the critical design tool for software development is a mind well educated in design principles. It is not UML or any other technology." Thus, the GRASP principles are really a mental toolset, a learning aid to help in the design of object-oriented software.
Patterns
In object-oriented design, a pattern is a named description of a problem and solution that can be applied in new contexts; ideally, a pattern advises us on how to apply its solution in varying circumstances and considers the forces and trade-offs. Many patterns, given a specific category of problem, guide the assignment of responsibilities to objects.
Information expert
Problem: What is a basic principle by which to assign responsibilities to objects?
Solution: Assign responsibility to the class that has the information needed to fulfill it.
Information expert (also expert or the expert principle) is a principle used to determine where to delegate responsibilities such as methods, computed fields, and so on.
Using the principle of information expert, a general approach to assigning responsibilities is to look at a given responsibility, determine the information needed to fulfill it, and then determine where that information is stored.
This will lead to placing t
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https://en.wikipedia.org/wiki/Glial%20cell%20line-derived%20neurotrophic%20factor
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Glial cell line-derived neurotrophic factor (GDNF) is a protein that, in humans, is encoded by the GDNF gene. GDNF is a small protein that potently promotes the survival of many types of neurons. It signals through GFRα receptors, particularly GFRα1.
It is also responsible for the determination of spermatogonia into primary spermatocytes, i.e. it is received by RET proto-oncogene (RET) and by forming gradient with SCF it divides the spermatogonia into two cells. As the result there is retention of spermatogonia and formation of spermatocyte.
GDNF family of ligands (GFL)
GDNF was discovered in 1991, and is the first member of the GDNF family of ligands (GFL) found.
Function
GDNF is highly distributed throughout both the peripheral and central nervous system. It can be secreted by astrocytes, oligodendrocytes, Schwann cells, motor neurons, and skeletal muscle during the development and growth of neurons and other peripheral cells.
The GDNF gene encodes a highly conserved neurotrophic factor. The recombinant form of this protein was shown to promote the survival and differentiation of dopaminergic neurons in culture, and was able to prevent apoptosis of motor neurons induced by axotomy. GDNF is synthesized as a 211 amino acid-long protein precursor, pro-GDNF. The pre-sequence leads the protein to the endoplasmic reticulum for secretion. While secretion takes place, the protein precursor folds via a sulfide-sulfide bond and dimerizes. The protein then is modified by N-linked glycosylation during packaging and preparation in the Golgi apparatus. Finally, the protein precursor undergoes proteolysis due to a proteolytic consensus sequence in its C-terminus end and is cleaved to 134 amino acids. Proteases that play a role in the proteolysis of pro-GDNF into mature GDNF include furin, PACE4, PC5A, PC5B, and PC7. Because multiple proteases can cleave the protein precursor, four different mature forms of GDNF can be produced. The proteolytic processing of GDNF requires Sor
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https://en.wikipedia.org/wiki/Truncated%20regression%20model
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Truncated regression models are a class of models in which the sample has been truncated for certain ranges of the dependent variable. That means observations with values in the dependent variable below or above certain thresholds are systematically excluded from the sample. Therefore, whole observations are missing, so that neither the dependent nor the independent variable is known. This is in contrast to censored regression models where only the value of the dependent variable is clustered at a lower threshold, an upper threshold, or both, while the value for independent variables is available.
Sample truncation is a pervasive issue in quantitative social sciences when using observational data, and consequently the development of suitable estimation techniques has long been of interest in econometrics and related disciplines. In the 1970s, James Heckman noted the similarity between truncated and otherwise non-randomly selected samples, and developed the Heckman correction.
Estimation of truncated regression models is usually done via parametric maximum likelihood method. More recently, various semi-parametric and non-parametric generalisation were proposed in the literature, e.g., based on the local least squares approach or the local maximum likelihood approach, which are kernel based methods.
See also
Censored regression model
Sampling bias
Truncated distribution
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https://en.wikipedia.org/wiki/Weyl%27s%20inequality
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In linear algebra, Weyl's inequality is a theorem about the changes to eigenvalues of an Hermitian matrix that is perturbed. It can be used to estimate the eigenvalues of a perturbed Hermitian matrix.
Weyl's inequality about perturbation
Let and be n×n Hermitian matrices, with their respective eigenvalues ordered as follows:
Then the following inequalities hold:
and, more generally,
In particular, if is positive definite then plugging into the above inequalities leads to
Note that these eigenvalues can be ordered, because they are real (as eigenvalues of Hermitian matrices).
Weyl's inequality between eigenvalues and singular values
Let have singular values and eigenvalues ordered so that . Then
For , with equality for .
Applications
Estimating perturbations of the spectrum
Assume that is small in the sense that its spectral norm satisfies for some small . Then it follows that all the eigenvalues of are bounded in absolute value by . Applying Weyl's inequality, it follows that the spectra of the Hermitian matrices M and N are close in the sense that
Note, however, that this eigenvalue perturbation bound is generally false for non-Hermitian matrices (or more accurately, for non-normal matrices). For a counterexample, let be arbitrarily small, and consider
whose eigenvalues and do not satisfy .
Weyl's inequality for singular values
Let be a matrix with . Its singular values are the positive eigenvalues of the Hermitian augmented matrix
Therefore, Weyl's eigenvalue perturbation inequality for Hermitian matrices extends naturally to perturbation of singular values. This result gives the bound for the perturbation in the singular values of a matrix due to an additive perturbation :
where we note that the largest singular value coincides with the spectral norm .
Notes
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https://en.wikipedia.org/wiki/The%20Eyes%20of%20Darkness
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The Eyes of Darkness is a thriller novel by American writer Dean Koontz, released in 1981. The book focuses on a mother who sets out on a quest to find out if her son indeed died one year ago, or if he's still alive.
Plot
A year after her son Danny dies in an alleged accident on a camping trip, stage producer Tina Evans starts receiving paranormal signals insinuating that the boy is still alive. Having never seen Danny's deceased body, she plans to exhume his corpse to put her mind to rest. Assisting Tina is a newly acquainted lawyer Elliot Stryker, formerly working for Army Intelligence, with whom she is having an affair. They are soon targeted by assassins hired by Project Pandora and barely escape alive. Tina, strongly convinced that Danny is still alive, sets out to discover what really happened to her son and rescue him. Elliot accompanies her and the pair are chased by other agents instructed to kill them. Tina is telepathically guided by Danny to an underground lab in Sierra Nevada where her son has been subjected to horrific experiments by a top secret governmental organisation.
Characters
Christina (Tina) Evans – Danny's mother
Michael Evans – Danny's father and Tina's ex-husband
Elliot Stryker – Tina's partner and love interest
Danny Evans – Tina and Michael's son
Harold Kennebeck – judge
Carlton Dombey – scientist for Project Pandora
Aaron Zachariah – scientist for Project Pandora
George Alexander – boss of Project Pandora
Jack Morgan – pilot
Vivienne Neddler – Tina's house maid
Willis Bruckster – assassin hired by Project Pandora
Bob – assassin hired by Project Pandora
Vince – assassin hired by Project Pandora
Planned television adaptation
According to author Dean Koontz in the afterword of a 2008 paperback reissue, television producer Lee Rich purchased the rights for the book along with The Face of Fear, Darkfall, and a fourth unnamed novel for a television series based on Koontz's work. The Eyes of Darkness was assigned to Ann Powell a
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https://en.wikipedia.org/wiki/Pelvic%20pain
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Pelvic pain is pain in the area of the pelvis. Acute pain is more common than chronic pain. If the pain lasts for more than six months, it is deemed to be chronic pelvic pain. It can affect both the male and female pelvis.
Common causes in include: endometriosis in women, bowel adhesions, irritable bowel syndrome, and interstitial cystitis. The cause may also be a number of poorly understood conditions that may represent abnormal psychoneuromuscular function.
The role of the nervous system in the genesis and moderation of pain is explored. The importance of psychological factors is discussed, both as a primary cause of pain and as a factor which affects the pain experience. As with other chronic syndromes, the biopsychosocial model offers a way of integrating physical causes of pain with psychological and social factors.
Terminology
Pelvic pain is a general term that may have many causes, listed below.
The subcategorical term urologic chronic pelvic pain syndrome (UCPPS) is an umbrella term adopted for use in research into urologic pain syndromes associated with the male and female pelvis. UCPPS specifically refers to chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) in men and interstitial cystitis or painful bladder syndrome (IC/PBS) in women.
Cause
Genital pain and pelvic pain can arise from a variety of conditions, crimes, trauma, medical treatments, physical diseases, mental illness and infections. In some instances the pain is consensual and self-induced. Self-induced pain can be a cause for concern and may require a psychiatric evaluation.
Female
Many different conditions can cause female pelvic pain including:
Related to pregnancy
Pelvic girdle pain
Ectopic pregnancy—a pregnancy implanted outside the uterus.
Gynecologic (from more common to less common)
Dysmenorrhea—pain during the menstrual period.
Endometriosis—pain caused by uterine tissue that is outside the uterus. Endometriosis can be visually confirmed by laparoscopy in approxim
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https://en.wikipedia.org/wiki/Trabeculae%20carneae
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The trabeculae carneae (columnae carneae, or meaty ridges) are rounded or irregular muscular columns which project from the inner surface of the right and left ventricle of the heart. These are different from the pectinate muscles, which are present in the atria of the heart. In development, trabeculae carneae are among the first of the cardiac structures to develop in the embryonic cardiac tube. Further, throughout development some trabeculae carneae condense to form the myocardium, papillary muscles, chordae tendineae, and septum.
Types
There are two kinds:
Some are attached along their entire length on one side and merely form prominent ridges,
Others are fixed at their extremities but free in the middle, as in the moderator band in the right ventricle, or the papillary muscles that holds chordae tendinae, which are connected to cusps of valves to control flow of blood into the heart
Function
Trabeculae lie at the interface between intracardiac flow and the compact myocardium. Their fractal branching pattern helps to maintain cardiac performance in both healthy and failing hearts by increasing contractility and stroke work. Trabecular morphology is also important to intraventricular conduction, suggesting these complex structures are involved in cardiac electrophysiology as well as mechanical function. A condensation of trabecular fibres forms the moderator band which carries the right branch of the bundle of His.
The trabeculae carneae also serve a function similar to that of papillary muscles in that their contraction pulls on the chordae tendineae, preventing inversion of the mitral (bicuspid) and tricuspid valves towards the atrial chambers, which would lead to subsequent leakage of the blood back into the atria. By this action on the atrioventricular valves, backflow of the blood from the ventricles into the atria is prevented.
The trabeculae carneae and the papillary muscles make up a significant percentage of the ventricular mass in the heart (12-
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https://en.wikipedia.org/wiki/Infundibulum%20%28heart%29
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The infundibulum (also known as conus arteriosus) is a conical pouch formed from the upper and left angle of the right ventricle in the chordate heart, from which the pulmonary trunk arises. It develops from the bulbus cordis. Typically, the infundibulum refers to the corresponding internal structure, whereas the conus arteriosus refers to the external structure. Defects in infundibulum development can result in a heart condition known as tetralogy of Fallot.
A tendinous band extends upward from the right atrioventricular fibrous ring and connects the posterior surface of the infundibulum to the aorta. The infundibulum is the entrance from the right ventricle into the pulmonary artery and pulmonary trunk. The wall of the infundibulum is smooth.
Additional images
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https://en.wikipedia.org/wiki/Umbilic%20torus
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The umbilic torus or umbilic bracelet is a single-edged 3-dimensional shape. The lone edge goes three times around the ring before returning to the starting point. The shape also has a single external face. A cross section of the surface forms a deltoid.
The umbilic torus occurs in the mathematical subject of singularity theory, in particular in the classification of umbilical points which are determined by real cubic forms . The equivalence classes of such cubics form a three-dimensional real projective space and the subset of parabolic forms define a surface – the umbilic torus. Christopher Zeeman named this set the umbilic bracelet in 1976.
The torus is defined by the following set of parametric equations.
In sculpture
John Robinson created a sculpture Eternity based on the shape in 1989, this had a triangular cross-section rather than a deltoid of a true Umbilic bracelet. This appeared on the cover of Geometric Differentiation by Ian R. Porteous.
Helaman Ferguson has created a 27-inch (69 centimeters) bronze sculpture, Umbilic Torus, and it is his most widely known piece of art. In 2010, it was announced that Jim Simons had commissioned an Umbilic Torus sculpture to be constructed outside the Math and Physics buildings at Stony Brook University, in proximity to the Simons Center for Geometry and Physics. The torus is made out of cast bronze, and is mounted on a stainless steel column. The total weight of the sculpture is 65 tonnes, and has a height of . The torus has a diameter of , the same diameter as the granite base. Various mathematical formulas defining the torus are inscribed on the base. Installation was completed in September, 2012.
In literature
In the short story What Dead Men Tell by Theodore Sturgeon, the main action takes place in a seemingly endless corridor with the cross section of an equilateral triangle. At the end the protagonist speculates that the corridor is actually a triangular shape twisted back on itself like a Möbius strip but
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https://en.wikipedia.org/wiki/Baudline
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The baudline time-frequency browser is a signal analysis tool designed for scientific visualization. It runs on several Unix-like operating systems under the X Window System. Baudline is useful for real-time spectral monitoring, collected signals analysis, generating test signals, making distortion measurements, and playing back audio files.
Applications
Acoustic cryptanalysis
Audio codec lossy compression analysis
Audio signal processing
Bioacoustics research
Data acquisition (DAQ)
Gravitational Wave analysis
Infrasound monitoring
Musical acoustics
radar
Seismic data processing
SETI
Signal analysis
Software Defined Radio
Spectral analysis
Very low frequency (VLF) reception
WWV frequency measurement
Features
Spectrogram, Spectrum, Waveform, and Histogram displays
Fourier, Correlation, and Raster transforms
SNR, THD, SINAD, ENOB, SFDR distortion measurements
Channel equalization
Function generator
Digital down converter
Audio playing with real-time DSP effects like speed control, pitch scaling, frequency shifting, matrix surround panning, filtering, and digital gain boost
Audio recording of multiple channels
JACK Audio Connection Kit sound server support
Import AIFF, AU, WAV, FLAC, MP3, Ogg Vorbis, AVI, MOV, and other file formats
License
The old baudline version comes with no warranty and is free to download. The binaries may be used for any purpose, though no form of redistribution is permitted. The new baudline version is available via a subscription model and site license.
See also
Linux audio software
List of information graphics software
List of numerical analysis software
Digital signal processing
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https://en.wikipedia.org/wiki/Anterior%20median%20fissure%20of%20spinal%20cord
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The anterior median fissure of the spinal cord is a deep midline groove of the anterior/ventral spinal cord. It divides the white matter of the anterior spinal cord nearly in two. The spinal pia mater extends into the fissure to line the surfaces of the spinal cord.
Anatomy
It has an average depth of about 3 mm, but this is increased in the lower part of the spinal cord. It contains a double fold of pia mater. Its floor is formed by a transverse band of white matter - the anterior white commissure - which is perforated by blood vessels on their way to or from the central part of the spinal cord.
Relations
The anterior median fissure provides a groove in which the anterior spinal artery sits.
Clinical significance
Imaging
The anterior median fissure may be identified on computerized tomography (CT) myelograms, but more commonly on magnetic resonance imaging (MRI) scans. The AMF has a characteristic appearance on MRI scans that differs from the MRI appearance of the central canal.
Additional images
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https://en.wikipedia.org/wiki/Anterior%20funiculus
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In the spinal cord, the most lateral of the bundles of the ventral nerve roots is generally taken as a dividing line that separates the antero-lateral region into two parts: an anterior funiculus (or anterior column), between the anterior median fissure and the most lateral of the ventral nerve roots; and a lateral funiculus, between the exit of these roots and the posterolateral sulcus.
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https://en.wikipedia.org/wiki/Lateral%20funiculus
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The most lateral of the bundles of the anterior nerve roots is generally taken as a dividing line that separates the anterolateral system into two parts. These are the anterior funiculus, between the anterior median fissure and the most lateral of the anterior nerve roots, and the lateral funiculus (or lateral column) between the exit of these roots and the posterolateral sulcus.
The lateral funiculus transmits the contralateral corticospinal and spinothalamic tracts. A lateral cutting of the spinal cord results in the transection of both ipsilateral posterior column and lateral funiculus and this produces Brown-Séquard syndrome.
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https://en.wikipedia.org/wiki/Genghis%20Khan%20%28video%20game%29
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Genghis Khan, original full title , is a 1987 turn-based strategy game developed by Koei, originally released for the NEC PC-9801, MSX and Sharp X68000 in 1988, the DOS and NES in 1990, and the Amiga in 1990. It is actually the second game in the series, after a 1985 Aoki Ōkami to Shiroki Mejika, also for PC-88, PC-98, and MSX.
Plot
The game takes the player inside the virtual life of either Genghis Khan or one of his archrivals. The player must arrange marriages, father children, appoint family members to governmental positions, and fight in order to conquer the Old World. Armies must be drafted and soldiers must be trained if the player is to rule the lands from England to Japan.
Gameplay
The game has two different ways to play. The first is Mongol Conquest, which begins in the year 1175 A.D, which is a one player mode. Players assume control of Lord Temujin and they must conquer the land by keeping their economy stable, having their army ready to fight, and by attacking other lands. The second is World Conquest, where the goal is to conquer every opposing country.
World Conquest, which begins in the year 1206 A.D, is started by choosing the number of players and difficulty. It supports 1-4 players. Players must choose who they want to be; Genghis Khan (Mongols), Alexios I (Byzantine), Richard (England), or Yoritomo (Japan). Then each player must randomly select the stats of their leader and successors. The player must stop a random number to choose the certain stat. This is done until all stats are chosen for the certain character, but they can be redone. After everyone is ready to go, the game begins. The countries of Eurasia cycle through; when it goes through a country, it means they have used their turn. When it comes to a player's country, they get to make three choices. These choices include training the troops, buying a certain product/quantity from a merchant, drafting soldiers, sending a treaty, or going to war. Each act takes one choice away until th
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https://en.wikipedia.org/wiki/Postictal%20state
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The postictal state is the altered state of consciousness after an epileptic seizure. It usually lasts between 5 and 30 minutes, but sometimes longer in the case of larger or more severe seizures, and is characterized by drowsiness, confusion, nausea, hypertension, headache or migraine, and other disorienting symptoms.
The ictal period is the seizure itself; the interictal period is the time between seizures, when brain activity is more normal; and the preictal period is the time leading up to a seizure:
Ictal period refers to a physiologic state or event such as a seizure, stroke, or headache. The word originates from the Latin word ictus, meaning a blow or a stroke. In electroencephalography (EEG), the recording during a seizure is said to be "ictal". The following definitions refer to the temporal relation with seizures.
Pre-ictal refers to the state immediately before the actual seizure, stroke, or headache.
Post-ictal refers to the state shortly after the event.
Interictal refers to the period between seizures, or convulsions, that are characteristic of an epilepsy disorder. For most people with epilepsy, the interictal state corresponds to more than 99% of their life. The interictal period is often used by neurologists when diagnosing epilepsy since an EEG trace will often show small interictal spiking and other abnormalities known by neurologists as subclinical seizures. Interictal EEG discharges are those abnormal waveforms not associated with seizure symptoms.
Signs and symptoms
Jerome Engel defines the postictal state as "manifestations of seizure-induced reversible alterations in neuronal function but not structure." Commonly after a seizure, a person feels mentally and physically exhausted for up to one or two days. The most common complaint is an inability to think clearly, specifically "poor attention and concentration, poor short term memory, decreased verbal and interactive skills, and a variety of cognitive defects specific to individuals."
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https://en.wikipedia.org/wiki/Posterior%20median%20sulcus%20of%20spinal%20cord
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The posterior median sulcus is the posterior end of the posterior median septum of neuroglia of the spinal cord. The septum varies in depth from 4 to 6 mm, but diminishes considerably in the lower part of the spinal cord.
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https://en.wikipedia.org/wiki/Selcall
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Selcall (selective calling) is a type of squelch protocol used in radio communications systems, in which transmissions include a brief burst of sequential audio tones. Receivers that are set to respond to the transmitted tone sequence will open their squelch, while others will remain muted.
Selcall is a radio signalling protocol mainly in use in Europe, Asia, Australia and New Zealand, and continues to be incorporated in radio equipment marketed in those areas.
Details
The transmission of a selcall code involves the generation and sequencing of a series of predefined, audible tones. Both the tone frequencies, and sometimes the tone periods, must be known in advance by both the transmitter and the receiver. Each predefined tone represents a single digit. A series of tones therefore represents a series of digits that represents a number. The number encoded in a selcall burst is used to address one or more receivers. If the receiver is programmed to recognise a certain number, then it will un-mute its speaker so that the transmission can be heard; an unrecognised number is ignored and therefore the receiver remains muted.
Tone Sets
A selcall tone set contains 16 tones that represent 16 digits. The digits correspond to the 16 hexadecimal digits, i.e. 0-9 and A-F. Digits A-F are typically reserved for control purposes. For example, digit "E" is typically used as the repeat digit.
There are eight, well known, selcall tone sets.
Tone Periods
The physical characteristics of the transmitted sequence of tones is tightly controlled. Each tone is generated for a predefined period, in the order of tens of milliseconds. Each subsequent tone is transmitted immediately after the preceding one for the same period, until the sequence is complete.
Typical tone periods include; 20ms, 30ms (sometimes 33ms), 40ms, 50ms, 60ms, 70ms, 80ms, 90ms and 100ms.
The longer the tone period, the more reliable the decoding of the tone sequence. Naturally, the longer the tone period, the great
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https://en.wikipedia.org/wiki/Arrow%20%28symbol%29
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An arrow is a graphical symbol, such as ← or →, or a pictogram, used to point or indicate direction. In its simplest form, an arrow is a triangle, chevron, or concave kite, usually
affixed to a line segment or rectangle, and in more complex forms a representation of an actual arrow (e.g. ➵ U+27B5). The direction indicated by an arrow is the one along the length of the line or rectangle toward the single pointed end.
History
An older (medieval) convention is the manicule (pointing hand, 👈).
Pedro Reinel in c. 1504 first used the fleur-de-lis as indicating north in a compass rose;
the convention of marking the eastern direction with a cross is older (medieval).
Use of the arrow symbol does not appear to pre-date the 18th century. An early arrow symbol is found in an illustration of Bernard Forest de Bélidor's treatise L'architecture hydraulique, printed in France in 1737. The arrow is here used to illustrate the direction of the flow of water and of the water wheel's rotation. At about the same time, arrow symbols were used to indicate the flow of rivers in maps.
A trend toward abstraction, in which the arrow's fletching is removed, can be observed in the mid-to-late 19th century. The arrow can be seen in the work of Paul Klee. In a further abstraction of the symbol, John Richard Green's A Short History of the English People of 1874 contained maps by cartographer Emil Reich, which indicated army movements by curved lines, with solid triangular arrowheads placed intermittently along the lines.
Use of arrow symbols in mathematical notation is still younger and develops in the first half of the 20th century.
David Hilbert in 1922 introduced the arrow symbol representing logical implication.
The double-headed arrow representing logical equivalence was introduced by Albrecht Becker in Die Aristotelische Theorie der Möglichkeitsschlüsse, Berlin, 1933.
Usage
Arrows are universally recognised for indicating directions. They are widely used on signage and for wayfin
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https://en.wikipedia.org/wiki/Institut%20national%20de%20l%27audiovisuel
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The (abbrev. INA), () is a repository of all French radio and television audiovisual archives. Additionally it provides free access to archives of countries such as Afghanistan and Cambodia. It has its headquarters in Bry-sur-Marne.
Since 2006, it has allowed free online consultation on a website called ina.fr with a search tool indexing 100,000 archives of historical programs, for a total of 20,000 hours.
Recordings
In the 1980s, it issued a large number of recordings on the label France's Concert Records. In the 1990s it launched its own label INA mémoire as the historical recording label of the Institut national de l'audiovisuel, and of the archives of Radio France.
History
The was founded in 1975 by a law of 1974 with the purpose of conserving archives of audiovisual materials, research relating to them and professional training. In 1992, legal deposit was extended to television and radio, and the institute was to be the depository. This led to the establishment of the in 1995, with the aim of conserving and making its holdings available to researchers and students. It was opened to the public in October 1998, at the . In 2002, legal deposit was extended to cable and satellite television and in 2005 to terrestrial digital television. From September 2006, the institute has been responsible for archiving 17 radio and 45 television services amounting to 300,000 hours per year.
Presidents
See also
Groupe de Recherches Musicales
François Bayle
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https://en.wikipedia.org/wiki/Windows%20Live%20Mesh
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Windows Live Mesh (formerly known as Windows Live FolderShare, Live Mesh, and Windows Live Sync) is a discontinued free-to-use Internet-based file synchronization application by Microsoft designed to allow files and folders between two or more computers to be in sync with each other on Windows (Vista and later) and Mac OS X (v. 10.5 Leopard and later, Intel processors only) computers or the Web via SkyDrive. Windows Live Mesh also enabled remote desktop access via the Internet.
Windows Live Mesh was part of the Windows Live Essentials 2011 suite of software. However this application was replaced by SkyDrive for Windows application in Windows Essentials 2012 and later OneDrive in Windows 8/8.1/10. Microsoft announced on December 13, 2012, that Windows Live Mesh would be discontinued on February 13, 2013.
Features
Features of Windows Live Mesh include:
Ability to sync up to 200 folders with 100,000 files each (each file up to 40 GB) for PC-to-PC synchronization
Ability to sync up to 5 GB of files to "SkyDrive synced storage" in the cloud
Remote Desktop access via Windows Live Mesh and the Windows Live Devices web service
PC-to-PC synchronisation of application settings for applications such as:
Windows Internet Explorer - synchronisation of favorites and recently typed URLs between computers
Microsoft Office - synchronisation of dictionaries, Outlook email signatures, styles and templates between computers
History
FolderShare and Windows Live Sync
Microsoft bought FolderShare from ByteTaxi Inc. on November 3, 2005, and subsequently made it a part of their Windows Live range of services.
On March 10, 2008, Microsoft released its first user visible update to the then Windows Live FolderShare. This comprised a rewrite of the FolderShare website and an updated Windows Live FolderShare client. Support for discussion groups and Remote Desktop Search was also removed in the update. The new client had some user interface and branding updates and contained several bug fi
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https://en.wikipedia.org/wiki/Uranium%20mining
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Uranium mining is the process of extraction of uranium ore from the ground. Over 50 thousand tons of uranium were produced in 2019. Kazakhstan, Canada, and Australia were the top three uranium producers, respectively, and together account for 68% of world production. Other countries producing more than 1,000 tons per year included Namibia, Niger, Russia, Uzbekistan, the United States, and China. Nearly all of the world's mined uranium is used to power nuclear power plants. Historically uranium was also used in applications such as uranium glass or ferrouranium but those applications have declined due to the radioactivity of uranium and are nowadays mostly supplied with a plentiful cheap supply of depleted uranium which is also used in uranium ammunition. In addition to being cheaper, depleted uranium is also less radioactive due to a lower content of short-lived and than natural uranium.
Uranium is mined by in-situ leaching (57% of world production) or by conventional underground or open-pit mining of ores (43% of production). During in-situ mining, a leaching solution is pumped down drill holes into the uranium ore deposit where it dissolves the ore minerals. The uranium-rich fluid is then pumped back to the surface and processed to extract the uranium compounds from solution. In conventional mining, ores are processed by grinding the ore materials to a uniform particle size and then treating the ore to extract the uranium by chemical leaching. The milling process commonly yields dry powder-form material consisting of natural uranium, "yellowcake," which is nowadays commonly sold on the uranium market as U3O8. While some nuclear power plants – most notably heavy water reactors like the CANDU – can operate with natural uranium (usually in the form of uranium dioxide), the vast majority of commercial nuclear power plants and many research reactors require uranium enrichment, which raises the content of from the natural 0.72% to 3–5% (for use in light water reacto
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https://en.wikipedia.org/wiki/Sulfur%20assimilation
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Sulfur assimilation is the process by which living organisms incorporate sulfur into their biological molecules. In plants, sulfate is absorbed by the roots and then be transported to the chloroplasts by the transipration stream where the sulfur are reduced to sulfide with the help of a series of enzymatic reactions. Furthermore, the reduced sulfur is incorporated into cysteine, an amino acid that is a precursor to many other sulfur-containing compounds. In animals, sulfur assimilation occurs primarily through the diet, as animals cannot produce sulfur-containing compounds directly. Sulfur is incorporated into amino acids such as cysteine and methionine, which are used to build proteins and other important molecules. Besides, With the rapid development of economy, the increase emission of sulfur results in environmental issues, such as acid rain and hydrogen sulfilde.
Sulfate uptake by plants
Sulfate is taken up by the roots that have high affinity. The maximal sulfate uptake rate is generally already reached at sulfate levels of 0.1 mM and lower. The uptake of sulfate by the roots and its transport to the shoot is strictly controlled and it appears to be one of the primary regulatory sites of sulfur assimilation.
Sulfate is actively taken up across the plasma membrane of the root cells, subsequently loaded into the xylem vessels and transported to the shoot by the transpiration stream. The uptake and transport of sulfate is energy dependent (driven by a proton gradient generated by ATPases) through a proton/sulfate co-transport. In the shoot the sulfate is unloaded and transported to the chloroplasts where it is reduced. The remaining sulfate in plant tissue is predominantly present in the vacuole, since the concentration of sulfate in the cytoplasm is kept rather constant.
Distinct sulfate transporter proteins mediate the uptake, transport and subcellular distribution of sulfate. According to their cellular and subcellular gene expression, and possible functio
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https://en.wikipedia.org/wiki/IDRO%20Group
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The Industrial Development & Renovation Organization of Iran (IDRO) known as IDRO Group was established in 1967 in Iran. IDRO Group is one of the largest companies in Iran. It is also one of the largest conglomerates in Asia. IDRO's objective is to develop Iran's industry sector and to accelerate the industrialization process of the country and to export Iranian products worldwide. Today, IDRO owns 117 subsidiaries and affiliated companies both domestically as well as internationally.
Businesses
In the course of its 40 years of activity, IDRO has gradually become a major shareholder of some key industries in Iran. In recent years and in accordance with the country's privatization policy, IDRO has made great efforts to privatize its affiliated companies. While carrying on its privatization policies and lessening its role as a holding company, IDRO intends to concentrate on its prime missions and to turn into an industrial development agency.
IDRO has focused its activities on the following areas in order to materialize such strategy and to expedite the industrial development of Iran:
Promotion of local and foreign investments with minority holdings owned by IDRO (less than 50% of the shares) with particular emphasis on new, hi-tech and export-oriented industries.
Restructuring the existing industries through participation of reputable foreign companies in order to transfer new technologies and to enhance the non-oil exports of Iran.
Development of general contracting activities with the participation of the Iranian private sector and credible foreign companies.
Rendering consultancy and support services to foreign investors.
Privatization of the existing subsidiaries.
Industrial Investment
Management Development
Automotive Industry
Industrial Equipment Machinery
Marine Industry
Railway Industry
Hi-Tech Industries Development
General Contracting
Health care
Banking
Privatization
IDRO had privatized 140 of its companies worth about 2,000 billion rials ($200 milli
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https://en.wikipedia.org/wiki/Random%20permutation%20statistics
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The statistics of random permutations, such as the cycle structure of a random permutation are of fundamental importance in the analysis of algorithms, especially of sorting algorithms, which operate on random permutations. Suppose, for example, that we are using quickselect (a cousin of quicksort) to select a random element of a random permutation. Quickselect will perform a partial sort on the array, as it partitions the array according to the pivot. Hence a permutation will be less disordered after quickselect has been performed. The amount of disorder that remains may be analysed with generating functions. These generating functions depend in a fundamental way on the generating functions of random permutation statistics. Hence it is of vital importance to compute these generating functions.
The article on random permutations contains an introduction to random permutations.
The fundamental relation
Permutations are sets of labelled cycles. Using the labelled case of the Flajolet–Sedgewick fundamental theorem and writing for the set of permutations and for the singleton set, we have
Translating into exponential generating functions (EGFs), we have
where we have used the fact that the EGF of the combinatorial species of permutations (there are n! permutations of n elements) is
This one equation allows one to derive a large number of permutation statistics. Firstly, by dropping terms from , i.e. exp, we may constrain the number of cycles that a permutation contains, e.g. by restricting the EGF to we obtain permutations containing two cycles. Secondly, note that the EGF of labelled cycles, i.e. of , is
because there are k! / k labelled cycles. This means that by dropping terms from this generating function, we may constrain the size of the cycles that occur in a permutation and obtain an EGF of the permutations containing only cycles of a given size.
Instead of removing and selecting cycles, one can also put different weights on different size cycles. If
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https://en.wikipedia.org/wiki/Midy%27s%20theorem
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In mathematics, Midy's theorem, named after French mathematician E. Midy, is a statement about the decimal expansion of fractions a/p where p is a prime and a/p has a repeating decimal expansion with an even period . If the period of the decimal representation of a/p is 2n, so that
then the digits in the second half of the repeating decimal period are the 9s complement of the corresponding digits in its first half. In other words,
For example,
Extended Midy's theorem
If k is any divisor of h (where h is the number of digits of the period of the decimal expansion of a/p (where p is again a prime)), then Midy's theorem can be generalised as follows. The extended Midy's theorem states that if the repeating portion of the decimal expansion of a/p is divided into k-digit numbers, then their sum is a multiple of 10k − 1.
For example,
has a period of 18. Dividing the repeating portion into 6-digit numbers and summing them gives
Similarly, dividing the repeating portion into 3-digit numbers and summing them gives
Midy's theorem in other bases
Midy's theorem and its extension do not depend on special properties of the decimal expansion, but work equally well in any base b, provided we replace 10k − 1 with bk − 1 and carry out addition in base b.
For example, in octal
In duodecimal (using inverted two and three for ten and eleven, respectively)
Proof of Midy's theorem
Short proofs of Midy's theorem can be given using results from group theory. However, it is also possible to prove Midy's theorem using elementary algebra and modular arithmetic:
Let p be a prime and a/p be a fraction between 0 and 1. Suppose the expansion of a/p in base b has a period of ℓ, so
where N is the integer whose expansion in base b is the string a1a2...aℓ.
Note that b ℓ − 1 is a multiple of p because (b ℓ − 1)a/p is an integer. Also bn−1 is not a multiple of p for any value of n less than ℓ, because otherwise the repeating period of a/p in base b would be less than ℓ.
Now
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https://en.wikipedia.org/wiki/Database%20machine
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A database machines or back end processor is a computer or special hardware that stores and retrieves data from a database. It is specially designed for database access and is tightly coupled to the main (front-end) computer(s) by a high-speed channel, whereas a database server is a general-purpose computer that holds a database and it's loosely coupled via a local area network to its clients.
Database machines can retrieve large amount of data using hundreds to thousands of microprocessors with database software. The front end processor asks the back end (typically sending a query expressed in a query language) the data and further processes it. The back end processor on the other hand analyzes and stores the data from the front end processor. Back end processors result in higher performance, increasing host main memory, increasing database recovery and security, and decreasing cost to manufacture.
Britton-Lee (IDM), Tandem (Non-Stop System), and Teradata (DBC) all offered early commercial specialized database machines. A more recent example was Oracle Exadata.
Criticism and suggested remedy
According to Julie McCann,
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https://en.wikipedia.org/wiki/Pizzino
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Pizzino (; plural as pizzini) is an Italian language word derived from the Sicilian language equivalent pizzinu meaning "small piece of paper". The word has been widely used to refer to small slips of paper that the Sicilian Mafia uses for high-level communications.
Sicilian Mafia boss Bernardo Provenzano is among those best known for using pizzini, most notably in his instruction that Matteo Messina Denaro become his successor. The pizzini of other mafiosi have significantly aided police investigations.
Provenzano case
Provenzano used a version of the Caesar cipher, used by Julius Caesar in wartime communications. The Caesar code involves shifting each letter of the alphabet forward three places; Provenzano's pizzini code did the same, then replaced letters with numbers indicating their position in the alphabet.
For example, one reported note by Provenzano read "I met 512151522 191212154 and we agreed that we will see each other after the holidays...". This name was decoded as "Binnu Riina".
Discovery Channel News quotes cryptography expert Bruce Schneier saying "Looks like kindergarten cryptography to me. It will keep your kid sister out, but it won't keep the police out. But what do you expect from someone who is computer illiterate?".
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https://en.wikipedia.org/wiki/Inverse%20scattering%20transform
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In mathematics, the inverse scattering transform is a method for solving some non-linear partial differential equations. The method is a non-linear analogue, and in some sense generalization, of the Fourier transform, which itself is applied to solve many linear partial differential equations. The name "inverse scattering method" comes from the key idea of recovering the time evolution of a potential from the time evolution of its scattering data: inverse scattering refers to the problem of recovering a potential from its scattering matrix, as opposed to the direct scattering problem of finding the scattering matrix from the potential.
The inverse scattering transform may be applied to many of the so-called exactly solvable models, that is to say completely integrable infinite dimensional systems.
Overview
The inverse scattering transform was first introduced by for the Korteweg–de Vries equation, and soon extended to the nonlinear Schrödinger equation, the Sine-Gordon equation, and the Toda lattice equation. It was later used to solve many other equations, such as the Kadomtsev–Petviashvili equation, the Ishimori equation, the Dym equation, and so on. A further family of examples is provided by the Bogomolny equations (for a given gauge group and oriented Riemannian 3-fold), the solutions of which are magnetic monopoles.
A characteristic of solutions obtained by the inverse scattering method is the existence of solitons, solutions resembling both particles and waves, which have no analogue for linear partial differential equations. The term "soliton" arises from non-linear optics.
The inverse scattering problem can be written as a Riemann–Hilbert factorization problem, at least in the case of equations of one space dimension. This formulation can be generalized to differential operators of order greater than 2 and also to periodic potentials.
In higher space dimensions one has instead a "nonlocal" Riemann–Hilbert factorization problem (with convolution i
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https://en.wikipedia.org/wiki/CCKM
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Cisco Centralized Key Management (CCKM) is a form of Fast Roaming and a subset of the Cisco Compatible EXtensions (CCX) specification.
When a wireless LAN is configured for fast reconnection, a Lightweight Extensible Authentication Protocol (LEAP) enabled client device can roam from one wireless access point to another without involving the main server. Using CCKM, an access point configured to provide Wireless Domain Services (WDS) takes the place of the RADIUS server, and authenticates the client without perceptible delay in voice or other time-sensitive applications.
The WDS (which can be run as a service on a Cisco Access Point or on various router modules) caches the user credentials after the initial log-on. The user must authenticate with the Radius server the first time – then they can roam between access points using cached credentials. This saves time in the roaming process, especially valuable for VoIP devices.
The current implementation of CCKM requires Cisco compatible hardware and either LEAP, EAP-FAST (CCXv3) or PEAP-GTC, PEAP-MSCHAP, EAP-TLS (CCXv4).
External links
http://www.cisco.com/web/partners/pr46/pr147/program_additional_information_new_release_features.html
Wireless networking
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https://en.wikipedia.org/wiki/Smithy%20code
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The Smithy code is a series of letters embedded, as a private amusement, within the April 2006 approved judgement of Mr Justice Peter Smith on The Da Vinci Code copyright case. It was first broken, in the same month, by Dan Tench, a lawyer who writes on media issues for The Guardian, after he received a series of email clues about it from Justice Smith.
How the code works
The letters in question are part of the actual text of the judgement, but italicised in contrast to the rest of the text. The following sequence of unusually emphasised letters can be extracted from the judgement document:
The italicised letters only occur up to paragraph 43 (which is page 13 of a 71-page document). Meanwhile, paragraph 52 concludes with this sentence: "The key to solving the conundrum posed by this judgment is in reading HBHG and DVC." (These abbreviations are used by Smith throughout the judgement in referring to the books at issue, The Holy Blood and the Holy Grail and The Da Vinci Code.)
There are 70 sections in the judgement. The source words from the judgement for the letters (with intervening words removed):
Letter frequencies
Excluding leading letters "s m i t h y c o d e", the letter frequencies are as follows:
a – 4
e – 3
g, m, p, q, s, t – 2
c, d, f, i, j, k, o, r, v, w, x, z – 1
Letter location
Paragraph numbers for cipher letters:
1 Claimant(s)
2
3
4
5 f(o)r
6
7
8
9
11
13
14
16
18 (t)he
19
20
21 u(s)ed
23 w(a)s
25
26
27
29
30
31 o(f)
34 (k)ey
35
37
38
40
42
43
Hints
From article "'Da Vinci' judgement code puzzles lawyers":
Solution
The cipher was a type of polyalphabetic cipher known as a Variant Beaufort, using a keyword based on the Fibonacci sequence, namely AAYCEHMU. This is the reverse of the Vigenère cipher, which here enables decryption rather than encryption.
Assigning each letter its place in the alphabet, the keyword corresponds to 1, 1, 25, 3, 5, 8, 13, 21. It is possible that the reason
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https://en.wikipedia.org/wiki/Binomial%20regression
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In statistics, binomial regression is a regression analysis technique in which the response (often referred to as Y) has a binomial distribution: it is the number of successes in a series of independent Bernoulli trials, where each trial has probability of success . In binomial regression, the probability of a success is related to explanatory variables: the corresponding concept in ordinary regression is to relate the mean value of the unobserved response to explanatory variables.
Binomial regression is closely related to binary regression: a binary regression can be considered a binomial regression with , or a regression on ungrouped binary data, while a binomial regression can be considered a regression on grouped binary data (see comparison). Binomial regression models are essentially the same as binary choice models, one type of discrete choice model: the primary difference is in the theoretical motivation (see comparison). In machine learning, binomial regression is considered a special case of probabilistic classification, and thus a generalization of binary classification.
Example application
In one published example of an application of binomial regression, the details were as follows. The observed outcome variable was whether or not a fault occurred in an industrial process. There were two explanatory variables: the first was a simple two-case factor representing whether or not a modified version of the process was used and the second was an ordinary quantitative variable measuring the purity of the material being supplied for the process.
Specification of model
The response variable Y is assumed to be binomially distributed conditional on the explanatory variables X. The number of trials n is known, and the probability of success for each trial p is specified as a function θ(X). This implies that the conditional expectation and conditional variance of the observed fraction of successes, Y/n, are
The goal of binomial regression is to estimate the fun
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https://en.wikipedia.org/wiki/Pubic%20tubercle
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The pubic tubercle is a prominent tubercle on the superior ramus of the pubis bone of the pelvis.
Structure
The pubic tubercle is a prominent forward-projecting tubercle on the upper border of the medial portion of the superior ramus of the pubis bone. The inguinal ligament attaches to it. Part of the abdominal external oblique muscle inserts onto it. The inferior epigastric artery passes between the pubic tubercle and the anterior superior iliac spine. The pubic spine is a rough ridge that extends from the pubic tubercle to the upper border of the pubic symphysis.
Clinical significance
The pubic tubercle may be palpated. It serves as a landmark for local anaesthetic of the genital branch of the genitofemoral nerve, which lies slightly lateral to the pubic tubercle. This may also be used for the obturator nerve.
Hernias
The pubic tubercle is a useful landmark for identifying hernias. An inguinal hernia will lie anteromedial to the pubic tubercle. A femoral hernia will lie inferolateral to the pubic tubercle.
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https://en.wikipedia.org/wiki/Co-occurrence%20matrix
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A co-occurrence matrix or co-occurrence distribution (also referred to as : gray-level co-occurrence matrices GLCMs) is a matrix that is defined over an image to be the distribution of co-occurring pixel values (grayscale values, or colors) at a given offset. It is used as an approach to texture analysis with various applications especially in medical image analysis.
Method
Given a grey-level image , co-occurrence matrix computes how often pairs of pixels with a specific value and offset occur in the image.
The offset, , is a position operator that can be applied to any pixel in the image (ignoring edge effects): for instance, could indicate "one down, two right".
An image with different pixel values will produce a co-occurrence matrix, for the given offset.
The value of the co-occurrence matrix gives the number of times in the image that the and pixel values occur in the relation given by the offset.
For an image with different pixel values, the co-occurrence matrix C is defined over an image , parameterized by an offset , as:
where: and are the pixel values; and are the spatial positions in the image I; the offsets define the spatial relation for which this matrix is calculated; and indicates the pixel value at pixel .
The 'value' of the image originally referred to the grayscale value of the specified pixel, but could be anything, from a binary on/off value to 32-bit color and beyond. (Note that 32-bit color will yield a 232 × 232 co-occurrence matrix!)
Co-occurrence matrices can also be parameterized in terms of a distance, , and an angle, , instead of an offset .
Any matrix or pair of matrices can be used to generate a co-occurrence matrix, though their most common application has been in measuring texture in images, so the typical definition, as above, assumes that the matrix is an image.
It is also possible to define the matrix across two different images. Such a matrix can then be used for color mapping.
Aliases
Co-occurrence mat
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https://en.wikipedia.org/wiki/Duhamel%27s%20integral
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In theory of vibrations, Duhamel's integral is a way of calculating the response of linear systems and structures to arbitrary time-varying external perturbation.
Introduction
Background
The response of a linear, viscously damped single-degree of freedom (SDOF) system to a time-varying mechanical excitation p(t) is given by the following second-order ordinary differential equation
where m is the (equivalent) mass, x stands for the amplitude of vibration, t for time, c for the viscous damping coefficient, and k for the stiffness of the system or structure.
If a system initially rests at its equilibrium position, from where it is acted upon by a unit-impulse at the instance t=0, i.e., p(t) in the equation above is a Dirac delta function δ(t), , then by solving the differential equation one can get a fundamental solution (known as a unit-impulse response function)
where is called the damping ratio of the system, is the natural angular frequency of the undamped system (when c=0) and is the angular frequency when damping effect is taken into account (when ). If the impulse happens at t=τ instead of t=0, i.e. , the impulse response is
，
Conclusion
Regarding the arbitrarily varying excitation p(t) as a superposition of a series of impulses:
then it is known from the linearity of system that the overall response can also be broken down into the superposition of a series of impulse-responses:
Letting , and replacing the summation by integration, the above equation is strictly valid
Substituting the expression of h(t-τ) into the above equation leads to the general expression of Duhamel's integral
Mathematical Proof
The above SDOF dynamic equilibrium equation in the case p(t)=0 is the homogeneous equation:
, where
The solution of this equation is:
The substitution: leads to:
One partial solution of the non-homogeneous equation: , where , could be obtained by the Lagrangian method for deriving partial solution of non-homogeneous ordinary differential equations
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https://en.wikipedia.org/wiki/Neural%20groove
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The neural groove is a shallow median groove of the neural plate between the neural folds of an embryo. The neural plate is a thick sheet of ectoderm surrounded on either side by the neural folds, two longitudinal ridges in front of the primitive streak of the developing embryo.
The groove gradually deepens as the neural folds become elevated, and ultimately the folds meet and coalesce in the middle line and convert the groove into a closed tube, the neural tube or canal, the ectodermal wall of which forms the rudiment of the nervous system.
After the coalescence of the neural folds over the anterior end of the primitive streak, the blastopore no longer opens on the surface but into the closed canal of the neural tube, and thus a transitory communication, the neurenteric canal, is established between the neural tube and the primitive digestive tube. The coalescence of the neural folds occurs first in the region of the hind-brain, and from there extends forward and backward; toward the end of the third week the front opening (anterior neuropore) of the tube finally closes at the anterior end of the future brain, and forms a recess which is in contact, for a time, with the overlying ectoderm; the hinder part of the neural groove presents for a time a rhomboidal shape, and to this expanded portion the term sinus rhomboidalis has been applied. Before the neural groove is closed a ridge of ectodermal cells appears along the prominent margin of each neural fold; this is termed the neural crest or ganglion ridge, and from it, the spinal and cranial nerve ganglia and the ganglia of the sympathetic nervous system are developed. By the upward growth of the mesoderm the neural tube is ultimately separated from the overlying ectoderm.
The cephalic end of the neural groove exhibits several dilatations, which, when the tube is closed, assume the form of three vesicles; these constitute the three primary cerebral vesicles and correspond respectively to the future fore-brain (p
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https://en.wikipedia.org/wiki/N-body%20simulation
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In physics and astronomy, an N-body simulation is a simulation of a dynamical system of particles, usually under the influence of physical forces, such as gravity (see n-body problem for other applications). N-body simulations are widely used tools in astrophysics, from investigating the dynamics of few-body systems like the Earth-Moon-Sun system to understanding the evolution of the large-scale structure of the universe. In physical cosmology, N-body simulations are used to study processes of non-linear structure formation such as galaxy filaments and galaxy halos from the influence of dark matter. Direct N-body simulations are used to study the dynamical evolution of star clusters.
Nature of the particles
The 'particles' treated by the simulation may or may not correspond to physical objects which are particulate in nature. For example, an N-body simulation of a star cluster might have a particle per star, so each particle has some physical significance. On the other hand, a simulation of a gas cloud cannot afford to have a particle for each atom or molecule of gas as this would require on the order of particles for each mole of material (see Avogadro constant), so a single 'particle' would represent some much larger quantity of gas (often implemented using Smoothed Particle Hydrodynamics). This quantity need not have any physical significance, but must be chosen as a compromise between accuracy and manageable computer requirements.
Dark Matter Simulation
Dark matter plays an important role in the formation of galaxies. The time evolution of the density f (in phase space) of dark matter particles, can be described by the collisionless Boltzmann equation
In the equation, is the velocity, and Φ is the gravitational potential given by Poisson's Equation. These two coupled equations are solved in an expanding background Universe, which is governed by the Friedmann equations, after determining the initial conditions of dark matter particles. The conventional meth
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https://en.wikipedia.org/wiki/Wright%20%28ADL%29
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In software architecture, Wright is an architecture description language developed at Carnegie Mellon University. Wright formalizes a software architecture in terms of concepts such as components, connectors, roles, and ports. The dynamic behavior of different ports of an individual component is described using the Communicating Sequential Processes (CSP) process algebra. The roles that different components interacting through a connector can take are also described using CSP. Due to the formal nature of the behavior descriptions, automatic checks of port/role compatibility, and overall system consistency can be performed.
Wright was principally developed by Robert Allen and David Garlan.
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https://en.wikipedia.org/wiki/Optic%20stalk
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The optic vesicles project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk.
Closure of the choroidal fissure in the optic stalk occurs during the seventh week of development. The former optic stalk is then called the optic nerve. In short, the optic stalks are the structures that precede the optic nerves embryologically.
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https://en.wikipedia.org/wiki/Optic%20vesicle
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The eyes begin to develop as a pair of diverticula (pouches) from the lateral aspects of the forebrain. These diverticula make their appearance before the closure of the anterior end of the neural tube; after the closure of the tube around the 4th week of development, they are known as the optic vesicles. Previous studies of optic vesicles suggest that the surrounding extraocular tissues – the surface ectoderm and extraocular mesenchyme – are necessary for normal eye growth and differentiation.
They project toward the sides of the head, and the peripheral part of each expands to form a hollow bulb, while the proximal part remains narrow and constitutes the optic stalk, which goes on to form the optic nerve.
Additional images
See also
Eye development
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https://en.wikipedia.org/wiki/Truth-bearer
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A truth-bearer is an entity that is said to be either true or false and nothing else. The thesis that some things are true while others are false has led to different theories about the nature of these entities. Since there is divergence of opinion on the matter, the term truth-bearer is used to be neutral among the various theories. Truth-bearer candidates include propositions, sentences, sentence-tokens, statements, beliefs, thoughts, intuitions, utterances, and judgements but different authors exclude one or more of these, deny their existence, argue that they are true only in a derivative sense, assert or assume that the terms are synonymous,
or seek to avoid addressing their distinction or do not clarify it.
Introduction
Some distinctions and terminology as used in this article, based on Wolfram 1989
(Chapter 2 Section1) follow.
It should be understood that the terminology described is not always used in the ways set out, and it is introduced solely for the purposes of discussion in this article. Use is made of the type–token and use–mention distinctions. Reflection on occurrences of numerals might be helpful.
In grammar a sentence can be a declaration, an explanation, a question, a command. In logic a declarative sentence is considered to be a sentence that can be used to communicate truth. Some sentences which are grammatically declarative are not logically so.
A character is a typographic character (printed or written) etc.
A word-token is a pattern of characters.
A word-type
is an identical pattern of characters.
A meaningful-word-token
is a meaningful pattern of characters.
Two word-tokens which mean the same are of the same word-meaning
A sentence-token is a pattern of word-tokens.
A meaningful-sentence-token
is a meaningful sentence-token or a meaningful pattern of meaningful-word-tokens.
Two sentence-tokens are of the same sentence-type if they are identical patterns of word-tokens characters
A declarative-sentence-token is a sentence-token wh
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https://en.wikipedia.org/wiki/Patlak%20plot
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A Patlak plot (sometimes called Gjedde–Patlak plot, Patlak–Rutland plot, or Patlak analysis) is a graphical analysis technique based on the compartment model that uses linear regression to identify and analyze pharmacokinetics of tracers involving irreversible uptake, such as in the case of deoxyglucose. It is used for the evaluation of nuclear medicine imaging data after the injection of a radioopaque or radioactive tracer.
The method is model-independent because it does not depend on any specific compartmental model configuration for the tracer, and the minimal assumption is that the behavior of the tracer can be approximated by two compartments – a "central" (or reversible) compartment that is in rapid equilibrium with plasma, and a "peripheral" (or irreversible) compartment, where tracer enters without ever leaving during the time of the measurements. The amount of tracer in the region of interest is accumulating according to the equation:
where represents time after tracer injection, is the amount of tracer in region of interest, is the concentration of tracer in plasma or blood, is the clearance determining the rate of entry into the peripheral (irreversible) compartment, and is the distribution volume of the tracer in the central compartment. The first term of the right-hand side represents tracer in the peripheral compartment, and the second term tracer in the central compartment.
By dividing both sides by , one obtains:
The unknown constants and can be obtained by linear regression from a graph of against .
See also
Logan plot
Positron emission tomography
Multi-compartment model
Binding potential
Deconvolution
Albert Gjedde
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https://en.wikipedia.org/wiki/John%20Guttag
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John Vogel Guttag (born March 6, 1949) is an American computer scientist, professor, and former head of the department of electrical engineering and computer science at MIT.
Education and career
John Guttag was raised in Larchmont, New York, the son of Irwin Guttag (1916–2005) and Marjorie Vogel Guttag.
John Vogel Guttag received a bachelor's degree in English from Brown University in 1971, and a master's degree in applied mathematics from Brown in 1972. In 1975, he received a doctorate in Computer Science from the University of Toronto. He was a member of the faculty at the University of Southern California from 1975 to 1978, and joined the Massachusetts Institute of Technology faculty in 1979.
From 1993 to 1998, he served as associate department head for computer science of MIT's electrical engineering and computer science Department. From January 1999 through August 2004, he served as head of that department. EECS, with approximately 2000 students and 125 faculty members, is the largest department at MIT.
He helped student Vanu Bose start a company with software-defined radio technology developed at MIT.
Guttag also co-heads the MIT Computer Science and Artificial Intelligence Laboratory's Networks and Mobile Systems Group. This group studies issues related to computer networks, applications of networked and mobile systems, and advanced software-based medical instrumentation and decision systems. He has also done research, published, and lectured in the areas of software engineering, mechanical theorem proving, hardware verification, compilation, software radios, and medical computing.
Guttag serves on the board of directors of Empirix and Avid Technology, and on the board of trustees of the Massachusetts General Hospital Institute of Health Professions. He is a member of the American Academy of Arts and Sciences. In 2006 he was inducted as a fellow of the Association for Computing Machinery.
He is one of the founders of Health[at]Scale Technologies, a mach
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https://en.wikipedia.org/wiki/Star-free%20language
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A regular language is said to be star-free if it can be described by a regular expression constructed from the letters of the alphabet, the empty set symbol, all boolean operators – including complementation – and concatenation but no Kleene star. The condition is equivalent to having generalized star height zero.
For instance, the language of all finite words over an alphabet can be shown to be star-free by taking the complement of the empty set, . Then, the language of words over the alphabet that do not have consecutive a's can be defined as , first constructing the language of words consisting of with an arbitrary prefix and suffix, and then taking its compliment, which must be all words which do not contain the substring .
An example of a regular language which is not star-free is , i.e. the language of strings consisting of an even number of "a". For where , the language can be defined as , taking the set of all words and removing from it words starting with , ending in or containing or . However, when , this definition does not create .
Marcel-Paul Schützenberger characterized star-free languages as those with aperiodic syntactic monoids. They can also be characterized logically as languages definable in FO[<], the first-order logic over the natural numbers with the less-than relation, as the counter-free languages and as languages definable in linear temporal logic.
All star-free languages are in uniform AC0.
See also
Star height
Generalized star height problem
Star height problem
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https://en.wikipedia.org/wiki/Raider%20Red
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Raider Red is one of the mascots of Texas Tech University. The university's primary mascot is The Masked Rider who rides a live horse. Raider Red is used at events where The Masked Rider is not allowed or would not be appropriate.
Around the 1971 football season, the Southwest Conference created a rule forbidding the bringing of live animal mascots to away games unless the host school permitted it. Since the Masked Rider's horse might have been prohibited from attending some games under this rule, Raider Red was created as an alternate mascot. Texas Tech now plays in the Big 12 Conference, but the tradition of having both mascots continues.
Jim Gaspard, a member of the Texas Tech Saddle Tramps student spirit organization, created the original design for the Raider Red costume based on a character created by Lubbock, Texas, cartoonist and former mayor Dirk West. Raider Red is a Wild West character with an oversized cowboy hat. He carries two guns which he fires into the air after Texas Tech scores.
The student serving as Raider Red is a member of the Saddle Tramps or High Riders. Although The Masked Rider's identity is public knowledge, Raider Red's identity is normally kept secret until the end of his or her tenure as mascot. The first Saddle Tramp to become Red Raider after Jim Gaspard was Stan Alcott from 1971 to 1973. The identity of Red Raider was known and Stan would wear the costume to the game. On March 15, 2007, it was revealed that, for the first time, two different people (one man and one woman) served as Raider Red during the same period of time.
In 2012, Raider Red won the Capital One Mascot Challenge, beating the University of South Carolina's Cocky in the final. He is known to his loyal fans as Jeffrey, thanks to the popular podcaster Dan "Big Cat" Katz.
In 2021 Raider Red took the National Cheerleading Associations Mascot Championships stage in Daytona, Florida for the first time in his 50 year lifespan. Raider Red won his first NCA Mascot Nat
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https://en.wikipedia.org/wiki/Obturator%20membrane
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The obturator membrane is a thin fibrous sheet, which almost completely closes the obturator foramen.
Its fibers are arranged in interlacing bundles mainly transverse in direction; the uppermost bundle is attached to the obturator tubercles and completes the obturator canal for the passage of the obturator vessels and nerve.
The membrane is attached to the sharp margin of the obturator foramen except at its lower lateral angle, where it is fixed to the pelvic surface of the inferior ramus of the ischium, i. e., within the margin.
Both obturator muscles are connected with this membrane.
Additional images
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https://en.wikipedia.org/wiki/Plasma%20channel
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A plasma channel is a conductive channel of plasma. A plasma channel can be formed in the following ways.
With a high-powered laser that operates at a certain frequency that will provide enough energy for an atmospheric gas to break into its ions, or form a plasma, such as in a Laser-Induced Plasma Channel, for example in an electrolaser.
With a voltage higher than the dielectric breakdown voltage applied across a dielectric, and dielectric breakdown occurs.
A plasma channel has a low electrical resistance and, once formed, will permit continuous current flow if the energy source that heats the plasma can be maintained. Unlike a normal electrical conductor, the resistance (and voltage drop) across an unconfined plasma channel decreases with increasing current flow, a property called negative resistance. As a result, an electric spark that initially required a very high voltage to initiate avalanche breakdown within the insulating gas will rapidly evolve into a hot, low-voltage electric arc if the electrical power source can continue to deliver sufficient power to the arc. Plasma channels tend to self constrict (see plasma pinch) due to magnetic forces stemming from the current flowing through the plasma.
On Earth, plasma channels are most frequently encountered in lightning storms.
See also
List of plasma (physics) articles
Plasma physics
Electromagnetism
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https://en.wikipedia.org/wiki/Ischial%20spine
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The ischial spine is part of the posterior border of the body of the ischium bone of the pelvis. It is a thin and pointed triangular eminence, more or less elongated in different subjects.
Structure
The pudendal nerve travels close to the ischial spine.
Clinical significance
The ischial spine can serve as a landmark in pudendal anesthesia, as the pudendal nerve lies close to the ischial spine.
Additional images
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https://en.wikipedia.org/wiki/Squared%20triangular%20number
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In number theory, the sum of the first cubes is the square of the th triangular number. That is,
The same equation may be written more compactly using the mathematical notation for summation:
This identity is sometimes called Nicomachus's theorem, after Nicomachus of Gerasa (c. 60 – c. 120 CE).
History
Nicomachus, at the end of Chapter 20 of his Introduction to Arithmetic, pointed out that if one writes a list of the odd numbers, the first is the cube of 1, the sum of the next two is the cube of 2, the sum of the next three is the cube of 3, and so on. He does not go further than this, but from this it follows that the sum of the first cubes equals the sum of the first odd numbers, that is, the odd numbers from 1 to . The average of these numbers is obviously , and there are of them, so their sum is
Many early mathematicians have studied and provided proofs of Nicomachus's theorem. claims that "every student of number theory surely must have marveled at this miraculous fact". finds references to the identity not only in the works of Nicomachus in what is now Jordan in the first century CE, but also in those of Aryabhata in India in the fifth century, and in those of Al-Karaji circa 1000 in Persia. mentions several additional early mathematical works on this formula, by Al-Qabisi (tenth century Arabia), Gersonides (circa 1300 France), and Nilakantha Somayaji (circa 1500 India); he reproduces Nilakantha's visual proof.
Numeric values; geometric and probabilistic interpretation
The sequence of squared triangular numbers is
These numbers can be viewed as figurate numbers, a four-dimensional hyperpyramidal generalization of the triangular numbers and square pyramidal numbers.
As observes, these numbers also count the number of rectangles with horizontal and vertical sides formed in an grid. For instance, the points of a grid (or a square made up of three smaller squares on a side) can form 36 different rectangles. The number of squares in a square gri
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https://en.wikipedia.org/wiki/Structure%20factor
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In condensed matter physics and crystallography, the static structure factor (or structure factor for short) is a mathematical description of how a material scatters incident radiation. The structure factor is a critical tool in the interpretation of scattering patterns (interference patterns) obtained in X-ray, electron and neutron diffraction experiments.
Confusingly, there are two different mathematical expressions in use, both called 'structure factor'. One is usually written ; it is more generally valid, and relates the observed diffracted intensity per atom to that produced by a single scattering unit. The other is usually written or and is only valid for systems with long-range positional order — crystals. This expression relates the amplitude and phase of the beam diffracted by the planes of the crystal ( are the Miller indices of the planes) to that produced by a single scattering unit at the vertices of the primitive unit cell. is not a special case of ; gives the scattering intensity, but gives the amplitude. It is the modulus squared that gives the scattering intensity. is defined for a perfect crystal, and is used in crystallography, while is most useful for disordered systems. For partially ordered systems such as crystalline polymers there is obviously overlap, and experts will switch from one expression to the other as needed.
The static structure factor is measured without resolving the energy of scattered photons/electrons/neutrons. Energy-resolved measurements yield the dynamic structure factor.
Derivation of
Consider the scattering of a beam of wavelength by an assembly of particles or atoms stationary at positions . Assume that the scattering is weak, so that the amplitude of the incident beam is constant throughout the sample volume (Born approximation), and absorption, refraction and multiple scattering can be neglected (kinematic diffraction). The direction of any scattered wave is defined by its scattering vector . ,
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https://en.wikipedia.org/wiki/Tendinous%20arch%20of%20pelvic%20fascia
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At the level of a line extending from the lower part of the pubic symphysis to the spine of the ischium is a thickened whitish band in this upper layer of the diaphragmatic part of the pelvic fascia. It is termed the tendinous arch or white line of the pelvic fascia, and marks the line of attachment of the special fascia (pars endopelvina fasciae pelvis) which is associated with the pelvic viscera.
It joins the fascia of the pubocervical fascia that covers the anterior wall of the vagina. If this fascia falls, the ipsilateral side of the vagina falls, carrying with it the bladder and the urethra, and thus contributing to urinary incontinence.
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https://en.wikipedia.org/wiki/Vertex%20model
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A vertex model is a type of statistical mechanics model in which the Boltzmann weights are associated with a vertex in the model (representing an atom or particle). This contrasts with a nearest-neighbour model, such as the Ising model, in which the energy, and thus the Boltzmann weight of a statistical microstate is attributed to the bonds connecting two neighbouring particles. The energy associated with a vertex in the lattice of particles is thus dependent on the state of the bonds which connect it to adjacent vertices. It turns out that every solution of the Yang–Baxter equation with spectral parameters in a tensor product of vector spaces yields an exactly-solvable vertex model.
Although the model can be applied to various geometries in any number of dimensions, with any number of possible states for a given bond, the most fundamental examples occur for two dimensional lattices, the simplest being a square lattice where each bond has two possible states. In this model, every particle is connected to four other particles, and each of the four bonds adjacent to the particle has two possible states, indicated by the direction of an arrow on the bond. In this model, each vertex can adopt possible configurations. The energy for a given vertex can be given by , with a state of the lattice is an assignment of a state of each bond, with the total energy of the state being the sum of the vertex energies. As the energy is often divergent for an infinite lattice, the model is studied for a finite lattice as the lattice approaches infinite size. Periodic or domain wall boundary conditions may be imposed on the model.
Discussion
For a given state of the lattice, the Boltzmann weight can be written as the product over the vertices of the Boltzmann weights of the corresponding vertex states
where the Boltzmann weights for the vertices are written
,
and the i, j, k, l range over the possible statuses of each of the four edges attached to the vertex. The vertex states
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https://en.wikipedia.org/wiki/Anterior%20humeral%20circumflex%20artery
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The anterior humeral circumflex artery (anterior circumflex artery, anterior circumflex humeral artery) is an artery in the arm. It is one of two circumflexing arteries that branch from the axillary artery, the other being the posterior humeral circumflex artery. The anterior humeral circumflex artery is considerably smaller than the posterior and arises nearly opposite to it, from the lateral side of the axillary artery.
Anatomy
Course and relations
The anterior humeral circumflex artery passes horizontally posterior to the coracobrachialis muscle and short head of the biceps brachii muscle, in and anterior to of the surgical neck of the humerus. Upon reaching the intertubercular sulcus, it issues off an ascending branch which ascends along the sulcus to supply the head of the humerus and the shoulder-joint. It continues laterally, deep to the long head of the biceps brachii and the deltoideus muscle before anastomosing with the posterior humeral circumflex artery.
Additional Images
See also
Posterior humeral circumflex artery
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https://en.wikipedia.org/wiki/Posterior%20humeral%20circumflex%20artery
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The posterior humeral circumflex artery (posterior circumflex artery, or posterior circumflex humeral artery) arises from the third part of the axillary artery at the distal border of the subscapularis.
Anatomy
Course and relations
It passes posteriorward with the axillary nerve through the quadrangular space. It winds laterally around the surgical neck of the humerus.
Distribution
It is distributed to the shoulder joint, teres major, teres minor, deltoid, and (long and lateral heads of) triceps brachii.
Anastomoses
It forms anastomoses with the anterior humeral circumflex artery, (deltoid branch of) profunda brachii artery, (acromial branches of) suprascapular artery, (acromial branches of) and thoracoacromial artery.
Additional images
See also
Anterior humeral circumflex artery
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https://en.wikipedia.org/wiki/Infraspinous%20fossa
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The infraspinous fossa (infraspinatus fossa or infraspinatous fossa) of the scapula is much larger than the supraspinatous fossa; toward its vertebral margin a shallow concavity is seen at its upper part; its center presents a prominent convexity, while near the axillary border is a deep groove which runs from the upper toward the lower part.
The medial two-thirds of the fossa give origin to the Infraspinatus; the lateral third is covered by this muscle.
Additional images
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https://en.wikipedia.org/wiki/Supraspinous%20fossa
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The supraspinous fossa (supraspinatus fossa, supraspinatous fossa) of the posterior aspect of the scapula (the shoulder blade) is smaller than the infraspinous fossa, concave, smooth, and broader at its vertebral than at its humeral end. Its medial two-thirds give origin to the Supraspinatus.
Structure
The fossa can be exposed by the removal of skin and the superficial fascia of the back and the trapezius muscle.
The supraspinous fossa is bounded by the spine of scapula on the inferior side, acromion process on the lateral side and the superior angle of scapula on the superior side.
Supraspinatus muscle originates from the supraspinous fossa. Distal attachment of the levator scapulae muscle is also on the medial aspect of the fossa.
Function
The suprascapular artery and nerve are found within the fossa. The posterior branch of the suprascapular artery supplies the supraspinatous muscle. Dorsal scapular artery also gives off a collateral branch and anastomoses with the suprascapular artery. Suprascapular nerve from the brachial plexus passes through the suprascapular notch as it approaches the fossa to supply the supraspinatus muscle. Suprascapular artery and nerve descend together but are separated by the superior transverse scapular ligament at the suprascapular notch.
Clinical significance
Rotator cuff tear
Hollowing in the supraspinous and the infraspinous area is frequently seen as chronic rotator cuff tear resulting in wasting. The wasting may be caused by the supraglenoid cyst compressing the suprascapular nerve and causes a loss of innervation to supraspinatus and infraspinatus muscles. Such wasting or hollowing can be differentially diagnosed as nerve compression or tendon rupture.
Additional images
See also
Supraspinatus muscle
Scapula
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https://en.wikipedia.org/wiki/Glenoid%20fossa
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The glenoid fossa of the scapula or the glenoid cavity is a bone part of the shoulder. The word glenoid is pronounced or (both are common) and is from , "socket", reflecting the shoulder joint's ball-and-socket form. It is a shallow, pyriform articular surface, which is located on the lateral angle of the scapula. It is directed laterally and forward and articulates with the head of the humerus; it is broader below than above and its vertical diameter is the longest.
This cavity forms the glenohumeral joint along with the humerus. This type of joint is classified as a synovial, ball and socket joint. The humerus is held in place within the glenoid cavity by means of the long head of the biceps tendon. This tendon originates on the superior margin of the glenoid cavity and loops over the shoulder, bracing humerus against the cavity. The rotator cuff also reinforces this joint more specifically with the supraspinatus tendon to hold the head of the humerus in the glenoid cavity.
The cavity surface is covered with cartilage in the fresh state, and its margins, slightly raised, give attachment to a fibrocartilaginous structure, the glenoid labrum, which deepens the cavity. This cartilage is very susceptible to tearing. When torn, it is most commonly known as a SLAP lesion which is generally caused by repetitive shoulder movements.
Compared to the acetabulum (at the hip-joint) the glenoid cavity is relatively shallow. This makes the shoulder joint prone to dislocation (luxation). Strong glenohumeral ligaments and muscles prevents dislocation in most cases.
By being so shallow the glenoid cavity allows the shoulder joint to have the greatest mobility of all joints in the body, allowing 120 degrees of unassisted flexion. Additional range of motion in shoulder flexion (typically up to 180 degrees in humans) is also accomplished by the great mobility of the scapula (shoulder blade) through a process known as scapulohumeral rhythm.
Evolution
Interpretations of the foss
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https://en.wikipedia.org/wiki/FCO-IM
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Fully Communication Oriented Information Modeling (FCO-IM) is a method for building conceptual information models. Such models can then be automatically transformed into entity-relationship models (ERM), Unified Modeling Language (UML), relational or dimensional models with the FCO-IM Bridge toolset, and it is possible to generate complete end-user applications from them with the IMAGine toolset. Both toolsets were developed by the Research and Competence Group Data Architectures & Metadata Management of the HAN University of Applied Sciences in Arnhem, the Netherlands.
Overview
FCO-IM is widely taught in the Netherlands and worldwide, amongst which are universities of Professional Education in the Netherlands. The method has proven its value, and is still actively used in multiple large-scale corporate environments. Branches covered vary from retail, logistics (KLM, ProRail), banking, insurance to medical companies (Erasmus MC).
FCO-IM includes an operational procedure specifying how to construct an information model as described in the book Fact Oriented Modeling.
The distinguishing feature of FCO-IM is that it models the communication about a certain Universe of Discourse (UoD) completely and exclusively, i.e.: it does not model the UoD itself, but rather the facts users exchange when they communicate about the UoD. FCO-IM is therefore a member of the family of information modeling techniques known as fact-oriented modeling (FOM), as are Object-Role Modeling (ORM), predicator set model (PSM) and natural language information analysis method (NIAM). Fact-oriented modeling is sometimes also indicated as fact-based modeling.
There are two main reasons why FCO-IM claims to be "fully communication-oriented".
FCO-IM is the only FOM technique that completely incorporates the actual verbalizations of facts by domain experts (fact expressions) in an information model. An FCO-IM model therefore contains the soft semantics – i.e.: the meaning of the facts – as well as
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https://en.wikipedia.org/wiki/Software%20management%20review
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A Software management review is a management study into a project's status and allocation of resources. It is different from both a software engineering peer review, which evaluates the technical quality of software products, and a software audit, which is an externally conducted audit into a project's compliance to specifications, contractual agreements, and other criteria.
Process
A management review can be an informal process, but generally requires a formal structure and rules of conduct, such as those advocated in the IEEE 1028 standard, which are:
Evaluate entry?
Management preparation?
Plan the structure of the review
Overview of review procedures?
[Individual] Preparation?
[Group] Examination?
Rework/follow-up?
[Exit evaluation]?
Definition
In software engineering, a management review is defined by the IEEE as:
A systematic evaluation of a software acquisition, supply, development, operation, or maintenance process performed by or on behalf of management ... [and conducted] to monitor progress, determine the status of plans and schedules, confirm requirements and their system allocation, or evaluate the effectiveness of management approaches used to achieve fitness for purpose. Management reviews support decisions about corrective actions, changes in the allocation of resources, or changes to the scope of the project.
Management reviews are carried out by, or on behalf of, the management personnel having direct responsibility for the system. Management reviews identify consistency with and deviations from plans, or adequacies and inadequacies of management procedures. This examination may require more than one meeting. The examination need not address all aspects of the product."
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https://en.wikipedia.org/wiki/Software%20peer%20review
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In software development, peer review is a type of software review in which a work product (document, code, or other) is examined by author's colleagues, in order to evaluate the work product's technical content and quality.
Purpose
The purpose of a peer review is to provide "a disciplined engineering practice for detecting and correcting defects in software artifacts, and preventing their leakage into field operations" according to the Capability Maturity Model.
When performed as part of each Software development process activity, peer reviews identify problems that can be fixed early in the lifecycle. That is to say, a peer review that identifies a requirements problem during the Requirements analysis activity is cheaper and easier to fix than during the Software architecture or Software testing activities.
The National Software Quality Experiment, evaluating the effectiveness of peer reviews, finds, "a favorable return on investment for software inspections; savings exceeds costs by 4 to 1". To state it another way, it is four times more costly, on average, to identify and fix a software problem later.
Distinction from other types of software review
Peer reviews are distinct from management reviews, which are conducted by management representatives rather than by colleagues, and for management and control purposes rather than for technical evaluation. They are also distinct from software audit reviews, which are conducted by personnel external to the project, to evaluate compliance with specifications, standards, contractual agreements, or other criteria.
Review processes
Peer review processes exist across a spectrum of formality, with relatively unstructured activities such as "buddy checking" towards one end of the spectrum, and more Informal approaches such as walkthroughs, technical peer reviews, and software inspections, at the other. The IEEE defines formal structures, roles, and processes for each of the last three.
Management representatives ar
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https://en.wikipedia.org/wiki/Null%20move
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In game theory, a null move or pass is a decision by a player to not make a move when it is that player's turn to move. Even though null moves are against the rules of many games, they are often useful to consider when analyzing these games. Examples of this include the analysis of zugzwang (a situation in chess or other games in which a null move, if it were allowed, would be better than any other move), and the null-move heuristic in game tree analysis (a method of pruning game trees involving making a null move and then searching to a lower depth).
The reason a reduced-depth null move is effective in game tree alpha-beta search reduction is that tactical threats tend to show up very quickly, in just one or two moves. If the opponent has no tactical threats revealed by null move search, the position may be good enough to exceed the best result obtainable in another branch of the tree (i.e. "beta"), so that no further search need be done from the current node, and the result from the null move can be returned as the search value. Even if the null move search value doesn't exceed beta, the returned value may set a higher floor on the valuation of the position than the present alpha, so more cutoffs will occur at descendant sibling nodes from the position.
The underlying assumption is that at least some legal move available to the player on move at the node is better than no move at all. In the case of the player on move being in zugzwang, that assumption is false, and the null move result is invalid (in that case, it actually sets a ceiling on the value of the position). Therefore it is necessary to have logic to exclude null moves at nodes in the tree where zugzwang is possible. In chess, zugzwang positions can occur in king and pawn endgames, and sometimes in end games that include other pieces as well.
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https://en.wikipedia.org/wiki/Colony%20%28video%20game%29
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Colony is an action-adventure game written by Ste Cork and released in 1987 for the Amstrad CPC, Atari 8-bit family, Commodore 64, MSX, and ZX Spectrum by Mastertronic on their Bulldog label.
Plot
Overpopulation has caused humanity to grow food in colonies on other planets. Unfortunately, the mushroom-growing planet that the player is responsible for is also inhabited by hostile native aliens which resemble giant insects. The player must use the droid under their control to maintain and harvest the mushrooms as well as look after and protect the colony itself.
Gameplay
Gameplay takes place in a flip-screen environment consisting of the colony itself (which is made-up of storehouses, some specialist buildings, mushroom fields and areas for solar panels) and the surrounding desert of the alien planet which is filled with various giant insects.
There are numerous things that the player must look-after.
Mushrooms
The purpose of the colony is to grow mushrooms for shipment back to Earth. These mushrooms will only grow in the green (i.e. lush) areas. They begin as seeds and quickly grow, eventually reaching a stage of maturity at which point they can be collected in order to be deposited for money and later for pick-up by a spacecraft. Unfortunately, the mushrooms are one of many things that the insects like to eat. The player can pick mature mushrooms which have been partially eaten by aliens but when deposited these will award no payment as they are unfit for human consumption.
Security fencing
The colony is surrounded by a security fence which keeps the giant insects out of the colony and from causing mischief therein. Unfortunately, the fence is constantly under attack by the insects who can chew their way through them. The player's droid must maintain the fence by destroying the marauding insects and replacing damaged or destroyed pieces of fence. Damaged fence sections can be deposited at a fence storehouse for repair. There are three different types of sec
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https://en.wikipedia.org/wiki/Mesonephric%20tubules
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Mesonephric tubules are genital ridges that are next to the mesonephros.
In males, some of the mesonephric kidney tubules, instead of being used to filter blood like the rest, "grow" over to the developing testes, penetrate them, and become connected to the seminiferous tubules of the testes. They also form the epididymis and the paradidymis.
The sperm differentiate inside the seminiferous tubules, then swim down these tubes, then through these special mesonephric tubules, and go down inside Wolffian duct, to the coelom and finally to the organ the animal uses to transport sperm into females.
In females, it gives rise to the epoophoron and the paroöphoron.
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https://en.wikipedia.org/wiki/Perron%27s%20formula
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In mathematics, and more particularly in analytic number theory, Perron's formula is a formula due to Oskar Perron to calculate the sum of an arithmetic function, by means of an inverse Mellin transform.
Statement
Let be an arithmetic function, and let
be the corresponding Dirichlet series. Presume the Dirichlet series to be uniformly convergent for . Then Perron's formula is
Here, the prime on the summation indicates that the last term of the sum must be multiplied by 1/2 when x is an integer. The integral is not a convergent Lebesgue integral; it is understood as the Cauchy principal value. The formula requires that c > 0, c > σ, and x > 0.
Proof
An easy sketch of the proof comes from taking Abel's sum formula
This is nothing but a Laplace transform under the variable change Inverting it one gets Perron's formula.
Examples
Because of its general relationship to Dirichlet series, the formula is commonly applied to many number-theoretic sums. Thus, for example, one has the famous integral representation for the Riemann zeta function:
and a similar formula for Dirichlet L-functions:
where
and is a Dirichlet character. Other examples appear in the articles on the Mertens function and the von Mangoldt function.
Generalizations
Perron's formula is just a special case of the Mellin discrete convolution
where
and
the Mellin transform. The Perron formula is just the special case of the test function for the Heaviside step function.
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https://en.wikipedia.org/wiki/DomainKeys%20Identified%20Mail
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DomainKeys Identified Mail (DKIM) is an email authentication method designed to detect forged sender addresses in email (email spoofing), a technique often used in phishing and email spam.
DKIM allows the receiver to check that an email that claimed to have come from a specific domain was indeed authorized by the owner of that domain. It achieves this by affixing a digital signature, linked to a domain name, to each outgoing email message. The recipient system can verify this by looking up the sender's public key published in the DNS. A valid signature also guarantees that some parts of the email (possibly including attachments) have not been modified since the signature was affixed. Usually, DKIM signatures are not visible to end-users, and are affixed or verified by the infrastructure rather than the message's authors and recipients.
DKIM is an Internet Standard. It is defined in RFC 6376, dated September 2011, with updates in RFC 8301 and RFC 8463.
Overview
The need for email validated identification arises because forged addresses and content are otherwise easily created—and widely used in spam, phishing and other email-based fraud. For example, a fraudster may send a message claiming to be from sender@example.com, with the goal of convincing the recipient to accept and to read the email—and it is difficult for recipients to establish whether to trust this message. System administrators also have to deal with complaints about malicious email that appears to have originated from their systems, but did not.
DKIM provides the ability to sign a message, and allows the signer (author organization) to communicate which email it considers legitimate. It does not directly prevent or disclose abusive behavior.
DKIM also provides a process for verifying a signed message. Verifying modules typically act on behalf of the receiver organization, possibly at each hop.
All of this is independent of Simple Mail Transfer Protocol (SMTP) routing aspects, in that it operates
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https://en.wikipedia.org/wiki/Marley%20%26%20Me
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Marley & Me: Life and Love with the World's Worst Dog is an autobiographical book by journalist John Grogan, published in 2005, about the 13 years he and his family spent with their yellow Labrador Retriever, Marley. The dog is poorly behaved and destructive, and the book covers the issues this causes in the family as they learn to accept him in addition to their grief following Marley's death. It was subsequently adapted by the author into three separate books, as well as into a comedy-drama film released in 2008.
Story
Told in first-person narrative, the book portrays Grogan and his family's life during the 13 years that they lived with their dog Marley, and the relationships and lessons from this period. Marley, a yellow Labrador Retriever, is described as a high-strung, boisterous, and somewhat uncontrolled dog. He is strong, powerful, endlessly hungry, eager to be active, and often destructive of their property (but completely without malice). Marley routinely fails to "get the idea" of what humans expect of him; at one point, mental illness is suggested as a plausible explanation for his behavior. His acts and behaviors are forgiven, however, since it is clear that he has a heart of gold and is merely living within his nature.
Marley was filmed for a two-minute credited appearance in the 1996 movie The Last Home Run.
The strong contrast between the problems and tensions caused by his neuroses and behavior, and the undying devotion, love and trust shown towards the human family as they themselves have children and grow up to accept him for what he is, and their grief when he finally dies from gastric dilatation volvulus (a stomach torsion condition) in old age, form the backdrop for the biographical material of the story.
In the autobiography, Grogan states that the eulogy he wrote in his newspaper following the death of his dog received more responses than any other column he had written in his professional life up until that point. In a discussion on his
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https://en.wikipedia.org/wiki/Primitive%20ventricle
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The primitive ventricle or embryonic ventricle of the developing heart, together with the bulbus cordis that lies in front of it, gives rise to the left and right ventricles. The primitive ventricle provides the trabeculated parts of the walls, and the bulbus cordis the smooth parts.
The primitive ventricle becomes divided by the septum inferius which develops into the interventricular septum. The septum grows upward from the lower part of the ventricle, at a position marked on the heart's surface by a furrow.
Its dorsal part increases more rapidly than its ventral portion, and fuses with the dorsal part of the septum intermedium.
For a time an interventricular foramen exists above its ventral portion, but this foramen is ultimately closed by the fusion of the aortic septum with the ventricular septum.
Additional images
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https://en.wikipedia.org/wiki/Primitive%20atrium
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The primitive atrium is a stage in the embryonic development of the human heart. It grows rapidly and partially encircles the bulbus cordis; the groove against which the bulbus cordis lies is the first indication of a division into right and left atria.
The cavity of the primitive atrium becomes subdivided into right and left chambers by a septum, the septum primum, which grows downward into the cavity.
For a time the atria communicate with each other by an opening, the primary interatrial foramen, below the free margin of the septum.
This opening is closed by the union of the septum primum with the septum intermedium, and the communication between the atria is re-established through an opening which is developed in the upper part of the septum primum; this opening is known as the foramen ovale (ostium secundum of Born) and persists until birth.
A second septum, the septum secundum, semilunar in shape, grows downward from the upper wall of the atrium immediately to the right of the primary septum and foramen ovale.
Shortly after birth it fuses with the primary septum, and by this means the foramen ovale is closed, but sometimes the fusion is incomplete and the upper part of the foramen remains patent. The limbus fossæ ovalis denotes the free margin of the septum secundum.
Issuing from each lung is a pair of pulmonary veins; each pair unites to form a single vessel, and these in turn join in a common trunk which opens into the left atrium.
Subsequently, the common trunk and the two vessels forming it expand and form the vestibule or greater part of the atrium, the expansion reaching as far as the openings of the four vessels, so that in the adult all four veins open separately into the left atrium.
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https://en.wikipedia.org/wiki/Cryptographic%20primitive
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Cryptographic primitives are well-established, low-level cryptographic algorithms that are frequently used to build cryptographic protocols for computer security systems. These routines include, but are not limited to, one-way hash functions and encryption functions.
Rationale
When creating cryptographic systems, designers use cryptographic primitives as their most basic building blocks. Because of this, cryptographic primitives are designed to do one very specific task in a precisely defined and highly reliable fashion.
Since cryptographic primitives are used as building blocks, they must be very reliable, i.e. perform according to their specification. For example, if an encryption routine claims to be only breakable with number of computer operations, and it is broken with significantly fewer than operations, then that cryptographic primitive has failed. If a cryptographic primitive is found to fail, almost every protocol that uses it becomes vulnerable. Since creating cryptographic routines is very hard, and testing them to be reliable takes a long time, it is essentially never sensible (nor secure) to design a new cryptographic primitive to suit the needs of a new cryptographic system. The reasons include:
The designer might not be competent in the mathematical and practical considerations involved in cryptographic primitives.
Designing a new cryptographic primitive is very time-consuming and very error-prone, even for experts in the field.
Since algorithms in this field are not only required to be designed well but also need to be tested well by the cryptologist community, even if a cryptographic routine looks good from a design point of view it might still contain errors. Successfully withstanding such scrutiny gives some confidence (in fact, so far, the only confidence) that the algorithm is indeed secure enough to use; security proofs for cryptographic primitives are generally not available.
Cryptographic primitives are similar in some ways to prog
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https://en.wikipedia.org/wiki/Jesus%20%28video%20game%29
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is a graphic adventure game developed and published by Enix. It was first released in 1987 on the PC-8801, FM-77AV, X1, and the MSX2 and was later ported to the Famicom in 1989 as (Jesus: Terror of Bio Monster). A sequel, Jesus II, was released on the PC-8801, PC-9801, and X68000 in 1991.
The game's name refers to a space station called J.E.S.U.S., named after the central Christian figure Jesus. The ship is shaped like a double-edged sword a la Book of Revelation. Its inhabitants go on to fight a mysterious demonic alien from Halley's Comet.
Plot
The game takes place in 2061. Halley's Comet has been approaching Mars and the nations of Earth send a mission to investigate.
Musou Hayao is stationed on the space lab Jesus. He speaks with his commanding officer on the station, who requests that he track down the members of the two crews being sent to the comet to deliver access cards. Hayao meets with 7 different crew members during this time: a Chinese doctor, German captain, Soviet captain, American xenobiologist, French mathematician, Italian computer engineer, and Brazilian astronomer. The mathematician is also Hayao's love interest, Eline. They share a heartfelt goodbye, as they would be boarding different ships for the mission which depart two weeks apart from another, with Eline's ship leaving for the comet first. Eline is a musician, and plays him a song that she wrote before he leaves.
Hayao's ship arrives at Halley's comet. Hayao is sent to investigate the first ship and finds most of the crew missing. Eline's intelligent robot pet Fojii is found in the ship's docking bay, and after updating its data offers Hayao assistance in tracking down the missing crew members. Unfortunately, many are found dead or dying, whispering dire warnings to Hayao about something sinister on board. A crew member tells Hayao that fire cannot hurt "it". None of the dead crew display any physical signs of harm except for a small pinprick on one of their fingers.
Hayao accesses
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https://en.wikipedia.org/wiki/Smallest%20grammar%20problem
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In data compression and the theory of formal languages, the smallest grammar problem is the problem of finding the smallest context-free grammar that generates a given string of characters (but no other string). The size of a grammar is defined by some authors as the number of symbols on the right side of the production rules.
Others also add the number of rules to that. The (decision version of the) problem is NP-complete.
The smallest context-free grammar that generates a given string is always a straight-line grammar without useless rules.
See also
Grammar-based code
Kolmogorov Complexity
Lossless data compression
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https://en.wikipedia.org/wiki/Purification%20theorem
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In game theory, the purification theorem was contributed by Nobel laureate John Harsanyi in 1973. The theorem aims to justify a puzzling aspect of mixed strategy Nash equilibria: that each player is wholly indifferent amongst each of the actions he puts non-zero weight on, yet he mixes them so as to make every other player also indifferent.
The mixed strategy equilibria are explained as being the limit of pure strategy equilibria for a disturbed game of incomplete information in which the payoffs of each player are known to themselves but not their opponents. The idea is that the predicted mixed strategy of the original game emerge as ever improving approximations of a game that is not observed by the theorist who designed the original, idealized game.
The apparently mixed nature of the strategy is actually just the result of each player playing a pure strategy with threshold values that depend on the ex-ante distribution over the continuum of payoffs that a player can have. As that continuum shrinks to zero, the players strategies converge to the predicted Nash equilibria of the original, unperturbed, complete information game.
The result is also an important aspect of modern-day inquiries in evolutionary game theory where the perturbed values are interpreted as distributions over types of players randomly paired in a population to play games.
Example
Consider the Hawk–Dove game shown here. The game has two pure strategy equilibria (Defect, Cooperate) and (Cooperate, Defect). It also has a mixed equilibrium in which each player plays Cooperate with probability 2/3.
Suppose that each player i bears an extra cost ai from playing Cooperate, which is uniformly distributed on [−A, A]. Players only know their own value of this cost. So this is a game of incomplete information which we can solve using Bayesian Nash equilibrium. The probability that ai ≤
. If player 2 Cooperates when , then player 1's expected utility from Cooperating is ; his expected utility from
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https://en.wikipedia.org/wiki/Radial%20spoke
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The radial spoke is a multi-unit protein structure found in the axonemes of eukaryotic cilia and flagella. Although experiments have determined the importance of the radial spoke in the proper function of these organelles, its structure and mode of action remain poorly understood.
Cellular location and structure
Radial spokes are T-shaped structures present inside the axoneme. Each spoke consists of a "head" and a "stalk," while each of these sub-structures is itself made up of many protein subunits. In all, the radial spoke is known to contain at least 17 different proteins, with 5 located in the head and at least 12 making up the stalk. The spoke stalk binds to the A-tubule of each microtubule outer doublet, and the spoke head faces in towards the center of the axoneme (see illustration at right).
Function
The radial spoke is known to play a role in the mechanical movement of the flagellum/cilium. For example, mutant organisms lacking properly functioning radial spokes have flagella and cilia that are immotile. Radial spokes also influence the cilium "waveform"; that is, the exact bending pattern the cilium repeats.
How the radial spoke carries out this function is poorly understood. Radial spokes are believed to interact with both the central pair microtubules and the dynein arms, perhaps in a way that maintains the rhythmic activation of the dynein motors. For example, one of the radial spoke subunits, RSP3, is an anchor protein predicted to hold another protein called protein kinase A (PKA). PKA would theoretically then be able to activate/inactivate the adjacent dynein arms via its kinase activity.
However, the identities and functions of the many radial spoke subunits are just beginning to be elucidated.
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https://en.wikipedia.org/wiki/Stationary%20state
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A stationary state is a quantum state with all observables independent of time. It is an eigenvector of the energy operator (instead of a quantum superposition of different energies). It is also called energy eigenvector, energy eigenstate, energy eigenfunction, or energy eigenket. It is very similar to the concept of atomic orbital and molecular orbital in chemistry, with some slight differences explained below.
Introduction
A stationary state is called stationary because the system remains in the same state as time elapses, in every observable way. For a single-particle Hamiltonian, this means that the particle has a constant probability distribution for its position, its velocity, its spin, etc. (This is true assuming the particle's environment is also static, i.e. the Hamiltonian is unchanging in time.) The wavefunction itself is not stationary: It continually changes its overall complex phase factor, so as to form a standing wave. The oscillation frequency of the standing wave, times Planck's constant, is the energy of the state according to the Planck–Einstein relation.
Stationary states are quantum states that are solutions to the time-independent Schrödinger equation:
where
This is an eigenvalue equation: is a linear operator on a vector space, is an eigenvector of , and is its eigenvalue.
If a stationary state is plugged into the time-dependent Schrödinger equation, the result is
Assuming that is time-independent (unchanging in time), this equation holds for any time . Therefore, this is a differential equation describing how varies in time. Its solution is
Therefore, a stationary state is a standing wave that oscillates with an overall complex phase factor, and its oscillation angular frequency is equal to its energy divided by .
Stationary state properties
As shown above, a stationary state is not mathematically constant:
However, all observable properties of the state are in fact constant in time. For example, if represents a simple one
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https://en.wikipedia.org/wiki/Pathophysiology%20of%20multiple%20sclerosis
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Multiple sclerosis is an inflammatory demyelinating disease of the CNS in which activated immune cells invade the central nervous system and cause inflammation, neurodegeneration, and tissue damage. The underlying cause is currently unknown. Current research in neuropathology, neuroimmunology, neurobiology, and neuroimaging, together with clinical neurology, provide support for the notion that MS is not a single disease but rather a spectrum.
There are three clinical phenotypes: relapsing-remitting MS (RRMS), characterized by periods of neurological worsening following by remissions; secondary-progressive MS (SPMS), in which there is gradual progression of neurological dysfunction with fewer or no relapses; and primary-progressive MS (MS), in which neurological deterioration is observed from onset.
Pathophysiology is a convergence of pathology with physiology. Pathology is the medical discipline that describes conditions typically observed during a disease state; whereas physiology is the biological discipline that describes processes or mechanisms operating within an organism. Referring to MS, the physiology refers to the different processes that lead to the development of the lesions and the pathology refers to the condition associated with the lesions.
Pathology
Multiple sclerosis can be pathologically defined as the presence of distributed glial scars (or sclerosis) in the central nervous system disseminated in time (DIT) and space (DIS). The gold standard for MS diagnosis is pathological correlation, though given its limited availability, other diagnosis methods are normally used. The scleroses that define the disease are the remainders of previous demyelinating lesions in the CNS white matter of a patient (encephalomyelitis) showing special characteristics, such as confluent instead of perivenous demyelination.
There are three phases for how an unknown underlying condition may cause damage in MS:
An unknown soluble factor (produced by CD8+ T-cells or CD2
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https://en.wikipedia.org/wiki/Granuloma%20annulare
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Granuloma annulare (GA) is a common, sometimes chronic skin condition which presents as reddish bumps on the skin arranged in a circle or ring. It can initially occur at any age, though two-thirds of patients are under 30 years old, and it is seen most often in children and young adults. Females are two times as likely to have it as males.
Signs and symptoms
Aside from the visible rash, granuloma annulare is usually asymptomatic. Sometimes the rash may burn or itch. People with GA usually notice a ring of small, firm bumps (papules) over the backs of the forearms, hands or feet, often centered on joints or knuckles. The bumps are caused by the clustering of T cells below the skin. These papules start as very small, pimple looking bumps, which spread over time from that size to dime, quarter, half-dollar size and beyond. Occasionally, multiple rings may join into one. Rarely, GA may appear as a firm nodule under the skin of the arms or legs. It also occurs on the sides and circumferential at the waist and without therapy can continue to be present for many years. Outbreaks continue to develop at the edges of the aging rings.
Causes
The condition is usually seen in otherwise healthy people. Occasionally, it may be associated with diabetes or thyroid disease. It has also been associated with autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, Lyme disease and Addison's disease. At this time, no conclusive connection has been made between patients.
Pathology
Granuloma annulare microscopically consists of dermal epithelioid histiocytes around a central zone of mucin—a so-called palisaded granuloma.
Pathogenesis
Granuloma annulare is an idiopathic condition, though many catalysts have been proposed. Among these is skin trauma, UV exposure, vaccinations, tuberculin skin testing, and Borrelia and viral infections.
The mechanisms proposed at a molecular level vary even more. In 1977, Dahl et al. proposed that since the lesions of GA often
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https://en.wikipedia.org/wiki/Semantic%20web%20service
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A semantic web service, like conventional web services, is the server end of a client–server system for machine-to-machine interaction via the World Wide Web. Semantic services are a component of the semantic web because they use markup which makes data machine-readable in a detailed and sophisticated way (as compared with human-readable HTML which is usually not easily "understood" by computer programs).
The problem addressed by Semantic Web Services
The mainstream XML standards for interoperation of web services specify only syntactic interoperability, not the semantic meaning of messages. For example, Web Services Description Language (WSDL) can specify the operations available through a web service and the structure of data sent and received but cannot specify semantic meaning of the data or semantic constraints on the data. This requires programmers to reach specific agreements on the interaction of web services and makes automatic web service composition difficult.
Semantic web services are built around universal standards for the interchange of semantic data, which makes it easy for programmers to combine data from different sources and services without losing meaning. Web services can be activated "behind the scenes" when a web browser makes a request to a web server, which then uses various web services to construct a more sophisticated reply than it would have been able to do on its own. Semantic web services can also be used by automatic programs that run without any connection to a web browser.
A semantic-web-services platform that uses OWL (Web Ontology Language) to allow data and service providers to semantically describe their resources using third-party ontologies is SSWAP: Simple Semantic Web Architecture and Protocol. SSWAP establishes a lightweight protocol (few OWL classes and predicates; see the SSWAP Protocol) and the concept of a "canonical graph" to enable providers to logically describe a service. A service is essentially a transformati
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https://en.wikipedia.org/wiki/Retail%2C%20Wholesale%20and%20Department%20Store%20Union
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Retail, Wholesale and Department Store Union (RWDSU) is a labor union in the United States. Founded in 1937, the RWDSU represents about 60,000 workers in a wide range of industries, including but not limited to retail, grocery stores, poultry processing, dairy processing, cereal processing, soda bottlers, bakeries, health care, hotels, manufacturing, public sector workers like crossing guards, sanitation, and highway workers, warehouses, building services, and distribution.
History
Montgomery Ward strike (1940s)
In 1943, the union organized a labor strike at the Montgomery Ward & Co. department store, after company management refused to comply with a War Labor Board order to recognize the union and institute the terms of a collective bargaining agreement the board had worked out. The strike involved nearly 12,000 workers in Jamaica, New York; Detroit, Michigan; Chicago, Illinois; St. Paul, Minnesota; Denver, Colorado; San Rafael, California; and Portland, Oregon. Ward's then cut wages and fired many union activists, with company chairman Sewell Avery later alleging "government has been coercing both employers and employees to accept a brand of unionism which in all too many cases is engineered by people who are not employees of the plant".
On April 26, 1944, President Franklin D. Roosevelt ordered US Army troops to seize the company's property in Chicago and remove Avery, who was forced out of his office by two troops. This ouster of Avery was based on charges he was impeding distribution of vital products during war. Jesse Holman Jones, the United States Secretary of Commerce, was installed as manager of the company's Chicago plant.
The workers again chose (via a National Labor Relations Board election) to form a collective bargaining organization in the summer of 1944, but Montgomery Ward continued to refuse to recognize the union. On December 27, 1944, Roosevelt issued an executive order authorizing the Secretary of War to seize all company property nation
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https://en.wikipedia.org/wiki/Software%20review
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A software review is "a process or meeting during which a software product is examined by a project personnel, managers, users, customers, user representatives, or other interested parties for comment or approval".
In this context, the term "software product" means "any technical document or partial document, produced as a deliverable of a software development activity", and may include documents such as contracts, project plans and budgets, requirements documents, specifications, designs, source code, user documentation, support and maintenance documentation, test plans, test specifications, standards, and any other type of specialist work product.
Varieties of software review
Software reviews may be divided into three categories:
Software peer reviews are conducted by one or more colleagues of the author, to evaluate the technical content and/or quality of the work.
Software management reviews are conducted by management representatives to evaluate the status of work done and to make decisions regarding downstream activities.
Software audit reviews are conducted by personnel external to the software project, to evaluate compliance with specifications, standards, contractual agreements, or other criteria.
Different types of peer reviews
Code review is systematic examination (often as peer review) of computer source code.
Pair programming is a type of code review where two persons develop code together at the same workstation.
Inspection is a very formal type of peer review where the reviewers are following a well-defined process to find defects.
Walkthrough is a form of peer review where the author leads members of the development team and other interested parties go through a software product and the participants ask questions and make comments about defects.
Technical review is a form of peer review in which a team of qualified personnel examines the suitability of the software product for its intended use and identifies discrepancies from specificat
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https://en.wikipedia.org/wiki/MagneRide
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MagneRide is an automotive adaptive suspension with magnetorheological damper system developed by the Delphi Automotive corporation, during a period when the company was a subsidiary of General Motors (GM), that uses magnetically controlled dampers, or shock absorbers, for a highly adaptive ride. As opposed to traditional suspension systems, MagneRide has no mechanical valves or even small moving parts that can wear out. This system consists of four monotube dampers, one on each corner of the vehicle, a sensor set, and an ECU (electronic control unit) to maintain the system.
Background
The dampers are filled with magnetorheological fluid, a mixture of easily magnetized iron particles in a synthetic hydrocarbon oil. In each of the monotube dampers is a piston containing two electromagnetic coils and two small fluid passages through the piston. The electromagnets are able to create a variable magnetic field across the fluid passages. When the magnets are off, the fluid travels through the passages freely. When the magnets are turned on, the iron particles in the fluid create a fibrous structure through the passages in the same direction as the magnetic field. The strength of the bonds between the magnetized iron particles causes the effective viscosity of the fluid to increase resulting in a stiffer suspension. Altering the strength of the current results in an instantaneous change in force of the piston. If the sensors sense any body roll, they communicate the information to the ECU. The ECU will compensate for this by changing the strength of the current to the appropriate dampers.
Differentiating features
Low-velocity damping control
Ability to "draw" force-velocity curve
Fast response
History
The first generation was created by Delphi Corporation during a period when it was a subsidiary of General Motors (GM), and debuted on the 2002.5 Cadillac Seville STS. The first sports car to use the technology was the 2003 C5 Corvette. The piston inside these dampers c
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https://en.wikipedia.org/wiki/International%20Year%20of%20Older%20Persons
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In its Proclamation on Aging, the United Nations General Assembly decided to declare 1999 as the International Year of Older Persons (IYOP). The proclamation was launched on 1 October 1998, the International Day of Older Persons, by United Nations Secretary General Kofi Annan.
Worldwide, within the next generations, the proportion of the population aged 60 and over will increase from one in four, bringing about significant social, economic and spiritual change. The proclamation was meant to draw attention to the recognition of humanity's demographic coming of age and the promise it holds for maturing attitudes and capabilities in social, economic, cultural and spiritual undertakings, not least for global peace and development in the next century.
Numerous events took place within the UN and in member countries to mark the event.
Theme
With these transformations in mind, the UN chose "towards a society for All Ages" to serve as the theme for IYOP. Throughout the year, participating countries will foster awareness of seniors' roles in society and the need for intergenerational respect and support, emphasizing the fact that older persons are the repository of their societies' histories.
The theme of this International Year, however, elicits the full engagement of all segments of society. It calls for "solidarity", "respect" and "exchanges" between generations. It calls for opportunities to share between the young and the not-so-young such that each may learn from the other.
History
Since 1959, World Refugee Year, the UN has designated specific years in order to draw attention to important issues. Governments of Member States, assisted by civil society, are encouraged to take the themes as opportunities to raise awareness and promote policy initiatives among citizens (The same rationale is applied to a lengthy list of annual days and special decades).
The work of many UN Agencies and programmes has direct connections with aging issues and will reflect IYOP prior
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https://en.wikipedia.org/wiki/Blood%20fractionation
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Blood fractionation is the process of fractionating whole blood, or separating it into its component parts. This is typically done by centrifuging the blood.
The resulting components are:
a clear solution of blood plasma in the upper phase (which can be separated into its own fractions, see Blood plasma fractionation),
the buffy coat, which is a thin layer of leukocytes (white blood cells) mixed with platelets in the middle, and
erythrocytes (red blood cells) at the bottom of the centrifuge tube.
Serum separation tubes (SSTs) are tubes used in phlebotomy containing a silicone gel; when centrifuged the silicone gel forms a layer on top of the buffy coat, allowing the blood serum to be removed more effectively for testing and related purposes.
As an alternative to energy-consuming centrifugation, more energy-efficient technologies have been studied, such as ultrasonic fractionation.
Plasma protein fractionation
Plasma proteins are separated by using the inherent differences of each protein. Fractionation involves changing the conditions of the pooled plasma (e.g., the temperature or the acidity) so that proteins that are normally dissolved in the plasma fluid become insoluble, forming large clumps, called precipitate. The insoluble protein can be collected by centrifugation. One of the very effective ways for carrying out this process is the addition of alcohol to the plasma membrane pool while simultaneously cooling the pool. This process is sometimes called cold alcohol fractionation or ethanol fractionation. It was described by and bears the eponym of Dr Edwin J. Cohn. This procedure is carried out in a series of steps so that a single pool of plasma yields several different protein products, such as albumin and immune globulin. Human serum albumin prepared by this process is used in some vaccines, for treating burn victims, and other medical applications.
See also
Blood plasma fractionation
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https://en.wikipedia.org/wiki/TiVo%20digital%20video%20recorders
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TiVo digital video recorders encompass a number of digital video recorder (DVR) models that TiVo Corporation designed. Features may vary, but a common feature is that all of the units listed here require TiVo service and use its operating system.
TiVo units have been manufactured by various OEMs, including Philips, Sony, Pioneer, Toshiba, and Humax. Cisco Systems and Samsung joined forces with pay TV Provider Virgin Media (UK-only) to create the Virgin Media TiVo box. The OEMs license the software from TiVo Corporation.
To date, there have been seven "series" of TiVo units produced, with the seventh series, the Edge, released in October 2019.
DVR models
Series1 (1999)
The Series1 (retronym) was the original TiVo digital video recorder.
Series1 TiVo systems are based on PowerPC processors connected to MPEG-2 encoder/decoder chips and IDE/ATA hard drives. Series1 TiVo units used one or two drives of 13–60 GB. Although not supported by TiVo or equipment manufacturers, larger drives can be added.
Series1 standalone
All standalone TiVo systems have coax/RF-in and an internal cable-ready tuner, analog video input—composite/RCA, and S-Video—for use with an external cable box or satellite receiver. The TiVo unit can use a serial cable or IR blasters to control the external receiver. They have coax/RF, composite/RCA, and S-Video output, and the DVD systems also have component out. Audio is RCA stereo, and the DVD systems also have digital optical out.
CPU: IBM PowerPC 403GCX at 54 MHz
RAM: 16 MB
Series1 DirecTV
Some TiVo systems are integrated with DirecTV receivers. These "DirecTiVo" recorders record the incoming satellite MPEG-2 digital stream directly to the hard disk without conversion. Because of this, and the fact that they have two tuners, DirecTiVos are able to record two programs at once. In addition, the lack of digital conversion allows recorded video to be of the same quality as live video. DirecTiVos have no MPEG encoder chip, and can only record D
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