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https://en.wikipedia.org/wiki/Navier%E2%80%93Stokes%20existence%20and%20smoothness
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The Navier–Stokes existence and smoothness problem concerns the mathematical properties of solutions to the Navier–Stokes equations, a system of partial differential equations that describe the motion of a fluid in space. Solutions to the Navier–Stokes equations are used in many practical applications. However, theoretical understanding of the solutions to these equations is incomplete. In particular, solutions of the Navier–Stokes equations often include turbulence, which remains one of the greatest unsolved problems in physics, despite its immense importance in science and engineering.
Even more basic (and seemingly intuitive) properties of the solutions to Navier–Stokes have never been proven. For the three-dimensional system of equations, and given some initial conditions, mathematicians have neither proved that smooth solutions always exist, nor found any counter-examples. This is called the Navier–Stokes existence and smoothness problem.
Since understanding the Navier–Stokes equations is considered to be the first step to understanding the elusive phenomenon of turbulence, the Clay Mathematics Institute in May 2000 made this problem one of its seven Millennium Prize problems in mathematics. It offered a US$1,000,000 prize to the first person providing a solution for a specific statement of the problem:
The Navier–Stokes equations
In mathematics, the Navier–Stokes equations are a system of nonlinear partial differential equations for abstract vector fields of any size. In physics and engineering, they are a system of equations that model the motion of liquids or non-rarefied gases (in which the mean free path is short enough so that it can be thought of as a continuum mean instead of a collection of particles) using continuum mechanics. The equations are a statement of Newton's second law, with the forces modeled according to those in a viscous Newtonian fluid—as the sum of contributions by pressure, viscous stress and an external body force. Since th
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https://en.wikipedia.org/wiki/Pressure%20drop
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Pressure drop (often abbreviated as "dP" or "ΔP") is defined as the difference in total pressure between two points of a fluid carrying network. A pressure drop occurs when frictional forces, caused by the resistance to flow, act on a fluid as it flows through a conduit (such as a channel, pipe, or tube). This friction converts some of the fluid’s hydraulic energy to thermal energy (i.e., internal energy). Since the thermal energy cannot be converted back to hydraulic energy, the fluid experiences a drop in pressure, as is required by conservation of energy.
The main determinants of resistance to fluid flow are fluid velocity through the pipe and fluid viscosity. Pressure drop increases proportionally to the frictional shear forces within the piping network. A piping network containing a high relative roughness rating as well as many pipe fittings and joints, tube convergence, divergence, turns, surface roughness, and other physical properties will affect the pressure drop. High flow velocities or high fluid viscosities result in a larger pressure drop across a pipe section, valve, or elbow joint. Low velocity will result in less (or no) pressure drop. The fluid may also be biphasic as in pneumatic conveying with a gas and a solid; in this case, the friction of the solid must also be taken into consideration for calculating the pressure drop.
Applications
Fluid in a system will always flow from a region of higher pressure to a region of lower pressure, assuming it has a path to do so. All things being equal, a higher pressure drop will lead to a higher flow (except in cases of choked flow).
The pressure drop of a given system will determine the amount of energy needed to convey fluid through that system. For example, a larger pump could be required to move a set amount of water through smaller-diameter pipes (with higher velocity and thus higher pressure drop) as compared to a system with larger-diameter pipes (with lower velocity and thus lower pressure drop).
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https://en.wikipedia.org/wiki/Pemphigoid
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Pemphigoid is a group of rare autoimmune blistering diseases of the skin, and mucous membranes. As its name indicates, pemphigoid is similar in general appearance to pemphigus, but, unlike pemphigus, pemphigoid does not feature acantholysis, a loss of connections between skin cells.
Pemphigoid is more common than pemphigus, and is slightly more common in women than in men. It is also more common in people aged over 70 years than it is in younger people.
Classification
IgG
The forms of pemphigoid are considered to be connective tissue autoimmune skin diseases. There are several types:
Gestational pemphigoid (PG) (formerly called Herpes gestationis)
Bullous pemphigoid (BP) Rarely affects the mouth
Mucous membrane pemphigoid (MMP) or (cicatricial pemphigoid), (No skin involvement)
Bullous and mucous membrane pemphigoid usually affect persons who are over age 60. Gestational pemphigoid occurs during pregnancy, typically in the second or third trimester, or immediately following pregnancy.
IgA
Pemphigoid is usually considered to be mediated by IgG, but IgA-mediated forms have also been described.
IgA-mediated immunobullous diseases can often be difficult to treat even with usually effective medications such as rituximab.
Bullous pemphigoid
Bullous pemphigoid is a rare and chronic autoimmune disorder characterised by large sub-epidermal blisters called bullae, that predominantly involves the skin and less commonly the mucous membranes. It is the most common type of the pemphigoid group, representing 80% of sub-epidermal immunobullous cases. It is more commonly known as cutaneous pemphigoid.
Presentation
Primary lesions of small and large blisters, known as vesicles and bullae, are found on the skin and sometimes on the mucous membranes.
Non-bullous pemphigoid
In some patients, pemphigoid starts off with cutaneous manifestations of BP without bullae, as the only sign of the disease. Pruritic eczematous, papular, or urticaria-like skin lesions may also per
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https://en.wikipedia.org/wiki/PCB%20Piezotronics
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PCB Piezotronics is a manufacturer of piezoelectric sensors.
The name "PCB" is abbreviation for "PicoCoulomB" which is technical terminology defining an electrical charge of the type generated by the piezoelectric sensors they manufacture. It is also a registered trademark of the company. "Piezotronics" combines the science of Piezoelectricity and electronics. PCB® manufactures sensors and related instrumentation. Sensors are small electromechanical instruments for the measurement of acceleration, dynamic pressure, force, acoustics, torque, load, strain, shock, vibration and sound.
History
Founded by Robert W. Lally and James (Jim) F. Lally in 1967, PCB Piezotronics has evolved from a family business to a large company engineering and manufacturing operation, with technical emphasis on the incorporation of integrated circuit-piezoelectric sensor technology. In 1967 the integrated circuit piezoelectric sensor, also known as ICP sensors, incorporated microelectronic circuitry, were developed and marketed.
The 1970s for PCB Piezotronics saw expansion of its standard product offerings, to include other types of sensor technologies. In 1971, the company developed a 100,000 g high-shock, ICP® quartz accelerometer; Impulse Hammers for structural excitation were developed in 1972; and in 1973, the first rugged, industrial-grade ICP® accelerometer was introduced to serve the emerging machinery health monitoring market. Employment grew to 25 employees. By 1975, PCB® had become one of the largest U.S. manufacturers of piezoelectric sensors.
During the 1980s, PCB® continued to develop new products. In 1982, the Structural* Modal Array Sensing System was developed to ease sensor installation and reduce set-up time on larger-scale modal surveys. Modally-Tuned* Impulse Hammers won the IR-100 Award as one of the top 100 technical developments for 1983. The 128-channel Data Harvester was invented in 1984 to provide sensor power and speed modal analysis by offering automatic
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https://en.wikipedia.org/wiki/Prolonged%20sine
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The law of the prolonged sine was observed when measuring strength of the reaction of the plant stems and roots in response to turning from their usual vertical orientation. Such organisms maintained their usual vertical growth, and, if turned, start bending back toward the vertical. The prolonged sine law was observed when measuring the dependence of the bending speed from the angle of reorientation.
The observed law
It was observed that deviation from the desired growth direction by more than the 90 degrees causes further increase of the bending speed. After turning the 135 degrees the reoriented plant or fungi understands that it is placed "head down" and bends faster than turned by just 45 degrees. Poul Larsen in 1962 proposed, that the intensity of the gravitropic reaction (bending rate) is proportional to
where α is the angle of reorientation, g - gravity vector and constants a and b are determined experimentally.
Significance
Following the popular hypothesis of the mechanism of the plant spatial orientation, the bending from the horizontal position is caused by some small heavy particles that after turning put the pressure on the side cell (statocyte) wall, irritating some system and activating the bending process. The pressure of such particle to the cell was would be proportional to the sine of the reorientation angle, being maximal at 90° reorientation. It would be equal for the reorientations by both 45° and 135°. The prolonged sine law concludes that there are very significant deviations from such a predicted reaction.
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https://en.wikipedia.org/wiki/Anterior%20interosseous%20nerve
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The anterior interosseous nerve (volar interosseous nerve) is a branch of the median nerve that supplies the deep muscles on the anterior of the forearm, except the ulnar (medial) half of the flexor digitorum profundus. Its nerve roots come from C8 and T1.
It accompanies the anterior interosseous artery along the anterior of the interosseous membrane of the forearm, in the interval between the flexor pollicis longus and flexor digitorum profundus, supplying the whole of the former and (most commonly) the radial half of the latter, and ending below in the pronator quadratus and wrist joint.
Note that the median nerve supplies all flexor muscles of the forearm except for the ulnar half of flexor digitorum profundus and the flexor carpi ulnaris, which is a superficial muscle of the forearm.
Innervation
The anterior interosseous nerve classically innervates 2.5 muscles:
which are deep muscles of the forearm
flexor pollicis longus
pronator quadratus
the radial (lateral) half of flexor digitorum profundus (inserting on the second and third digits)
and the inferior radioulnar, wrist and carpal joints.
Injury
A branch of the median nerve, the anterior interosseous nerve (AIN) can be affected by either direct penetrating injury, possibly compression in a fashion similar to carpal tunnel syndrome, but most commonly an idiopathic inflammatory process (referred to an Anterior Interosseous Syndrome). As might be expected, the symptoms involve weakness in the muscle innervated by the AIN including the flexor digitorum profundus muscle to the index (and sometimes the middle) finger, the flexor pollicis longus muscle to the thumb and the pronator quadratus of the distal forearm. AIN also has large sensory nerve to the volar wrist bones and compression of the AIN branch of the median nerve at the elbow can cause referred pain in the volar wrist/distal volar forearm. Non-surgical treatment consists of splinting, proximal tissue massage and anti-inflammatory drugs. Surgical t
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https://en.wikipedia.org/wiki/Armadillo%20repeat
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An armadillo repeat is a characteristic, repetitive amino acid sequence of about 42 residues in length that is found in many proteins. Proteins that contain armadillo repeats typically contain several tandemly repeated copies. Each armadillo repeat is composed of a pair of alpha helices that form a hairpin structure. Multiple copies of the repeat form what is known as an alpha solenoid structure.
Examples of proteins that contain armadillo repeats include β-catenin, Sarm1 (SARM1), α-importin, plakoglobin, adenomatous polyposis coli (APC), and many others.
The term armadillo derives from the historical name of the β-catenin gene in the fruitfly Drosophila where the armadillo repeat was first discovered. Although β-catenin was previously believed to be a protein involved in linking cadherin cell adhesion proteins to the cytoskeleton, recent work indicates that β-catenin regulates the homodimerization of alpha-catenin, which in turn controls actin branching and bundling. But, the armadillo repeat is found in a wide range of proteins with other functions. This type of protein domain is important in transducing WNT signals during embryonic development.
Structure
The 3-dimensional fold of an armadillo repeat was first observed in the crystal structure of β-catenin, where the 12 tandem repeats form a superhelix of alpha helices with three helices per unit. The cylindrical structure features a positively charged groove, which presumably interacts with the acidic surfaces of the known interaction partners of β-catenin.
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https://en.wikipedia.org/wiki/Palmar%20branch%20of%20ulnar%20nerve
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The palmar branch of the ulnar nerve arises about five cm proximal to the wrist from where the ulnar nerve splits into palmar and dorsal branches. It supplies sensory innervation to a small area in the palmar surface of the wrist.
The palmar branch represents the continuation of the ulnar nerve as it crosses the flexor retinaculum of the hand on the lateral side of the pisiform bone, medial to and a little behind the ulnar artery.
Some sources state that it ends by dividing into a superficial and a deep branch. (Other sources state that the superficial branch of ulnar nerve and deep branch of ulnar nerve are the terminal branches of the ulnar nerve itself.)
Additional Images
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https://en.wikipedia.org/wiki/Red%20Storm%20%28computing%29
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Red Storm is a supercomputer architecture designed for the US Department of Energy’s National Nuclear Security Administration Advanced Simulation and Computing Program. Cray, Inc developed it based on the contracted architectural specifications provided by Sandia National Laboratories. The architecture was later commercially produced as the
Cray XT3.
Red Storm is a partitioned, space shared, tightly coupled, massively parallel processing machine with a high performance 3D mesh network. The processors are commodity AMD Opteron CPUs with off-the-shelf memory DIMMs. The NIC/router combination, called SeaStar, is the only custom ASIC component in the system and uses a PowerPC 440 based core. When deployed in 2005, Red Storm’s initial configuration consisted of 10,880 single-core 2.0 GHz Opterons, of which 10,368 were dedicated for scientific calculations. The remaining 512 Opterons were used to service the computations and also provide the user interface to the system and run a version of Linux. This initial installation consisted of 140 cabinets, taking up of floor space.
The Red Storm supercomputer was designed to be highly scalable from a single cabinet to hundreds of cabinets and has been scaled-up twice. In 2006 the system was upgraded to 2.4 GHz Dual-Core Opterons. An additional fifth row of computer cabinets were also brought online resulting in over 26,000 processor cores. This resulted in a peak performance of 124.4 teraflops, or 101.4 running the Linpack benchmark.
A second major upgrade in 2008 introduced Cray XT4 technology: Quad-core Opteron processors and an increase in memory to 2 GB per core. This resulted in a peak theoretical performance of 284 teraflops.
Top500 performance ranking for Red Storm after each upgrade:
November 2005: Rank 6 (36.19 TFLOPS)
November 2006: Rank 2 (101.4 TFLOPS)
November 2008: Rank 9 (204.2 TFLOPS)
Red Storm is intended for capability computing. That is, a single application can be run on the entire system. This is in
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https://en.wikipedia.org/wiki/Dorsal%20branch%20of%20ulnar%20nerve
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The dorsal branch of ulnar nerve arises about 5 cm. proximal to the wrist; it passes backward beneath the Flexor carpi ulnaris, perforates the deep fascia, and, running along the ulnar side of the back of the wrist and hand, divides into two dorsal digital branches; one supplies the ulnar side of the little finger; the other, the adjacent sides of the little and ring fingers.
It also sends a twig to join that given by the superficial branch of the radial nerve for the adjoining sides of the middle and ring fingers, and assists in supplying them.
A branch is distributed to the metacarpal region of the hand, communicating with a twig of the superficial branch of the radial nerve.
Additional images
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https://en.wikipedia.org/wiki/Alpha%20max%20plus%20beta%20min%20algorithm
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The alpha max plus beta min algorithm is a high-speed approximation of the square root of the sum of two squares. The square root of the sum of two squares, also known as Pythagorean addition, is a useful function, because it finds the hypotenuse of a right triangle given the two side lengths, the norm of a 2-D vector, or the magnitude of a complex number given the real and imaginary parts.
The algorithm avoids performing the square and square-root operations, instead using simple operations such as comparison, multiplication, and addition. Some choices of the α and β parameters of the algorithm allow the multiplication operation to be reduced to a simple shift of binary digits that is particularly well suited to implementation in high-speed digital circuitry.
The approximation is expressed as
where is the maximum absolute value of a and b, and is the minimum absolute value of a and b.
For the closest approximation, the optimum values for and are and , giving a maximum error of 3.96%.
Improvements
When , becomes smaller than (which is geometrically impossible) near the axes where is near 0.
This can be remedied by replacing the result with whenever that is greater, essentially splitting the line into two different segments.
Depending on the hardware, this improvement can be almost free.
Using this improvement changes which parameter values are optimal, because they no longer need a close match for the entire interval. A lower and higher can therefore increase precision further.
Increasing precision: When splitting the line in two like this one could improve precision even more by replacing the first segment by a better estimate than , and adjust and accordingly.
Beware however, that a non-zero would require at least one extra addition and some bit-shifts (or a multiplication), probably nearly doubling the cost and, depending on the hardware, possibly defeat the purpose of using an approximation in the first place.
See also
Hypot,
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https://en.wikipedia.org/wiki/Proper%20palmar%20digital%20nerves%20of%20median%20nerve
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In the palm of the hand the median nerve is covered by the skin and the palmar aponeurosis, and rests on the tendons of the flexor muscles. Immediately after emerging from under the transverse carpal ligament the median nerve becomes enlarged and flattened and splits into a smaller, lateral, and a larger, medial portion.
The lateral portion supplies a short, stout branch to certain of the muscles of the ball of the thumb, viz., the abductor pollicis brevis, the opponens pollicis, and the superficial head of the flexor brevis, and then divides into three proper palmar digital nerves of median nerve (proper volar digital nerves):
two of these supply the sides of the thumb,
while the third gives a twig to the first lumbricalis and is distributed to the radial side of the index finger.
It also divides into two common palmar digital nerves:
The first of these divides into two proper digital nerves for the adjoining sides of the index and middle fingers;
the second common palmar digital nerve splits into two proper digital nerves for the adjoining sides of the third and fourth digits.
Each proper digital nerve, opposite the base of the first phalanx, gives off a dorsal branch which joins the dorsal digital nerve from the superficial branch of the radial nerve, and supplies the integument on the dorsal aspect of the last phalanx.
At the end of the digit, the proper digital nerve divides into two branches,
one of which supplies the pulp of the finger,
the other ramifies around and beneath the nail.
The proper digital nerves, as they run along the fingers, are placed superficial to the corresponding arteries.
See also
Common palmar digital nerves of median nerve
Additional images
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https://en.wikipedia.org/wiki/Common%20palmar%20digital%20nerves%20of%20median%20nerve
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In the palm of the hand the median nerve is covered by the skin and the palmar aponeurosis, and rests on the tendons of the Flexor muscles. Immediately after emerging from under the transverse carpal ligament the median nerve becomes enlarged and flattened and splits into a smaller, lateral, and a larger, medial portion.
The medial portion of the nerve divides into two Common palmar digital nerves (common volar digital nerves).
The first of these gives a twig to the second Lumbricalis and runs toward the cleft between the index and middle fingers, where it divides into two proper digital nerves for the adjoining sides of these digits;
the second runs toward the cleft between the middle and ring fingers, and splits into two proper digital nerves for the adjoining sides of these digits; it communicates with a branch from the ulnar nerve and sometimes sends a twig to the third Lumbricalis.
Additional images
See also
Proper palmar digital nerves of median nerve
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https://en.wikipedia.org/wiki/Gaillardia%20%C3%97%20grandiflora
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Gaillardia × grandiflora, known as blanket flower, is a hybrid species of flowering plant in the sunflower family Asteraceae, which is a cross of garden origin between G. aristata × G. pulchella.
Description
This herbaceous perennial and its cultivars are valued for their large ornamental blooms in summer and autumn. 'Dazzler', with orange flowers tipped with yellow, grows to tall by broad.
Cultivation
It is usually grown as a half-hardy annual, especially in cooler climates. It has won the Royal Horticultural Society's Award of Garden Merit.
Several other cultivars exist, in the same range of colours (red, orange and yellow).
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https://en.wikipedia.org/wiki/Palmar%20branch%20of%20the%20median%20nerve
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The palmar branch of the median nerve is a branch of the median nerve which arises at the distal part of the forearm.
Branches
It pierces the palmar carpal ligament, and divides into a lateral and a medial branch;
The lateral branch supplies the skin over the ball of the thumb, and communicates with the volar branch of the lateral antebrachial cutaneous nerve.
The medial branch supplies the skin of the palm and communicates with the palmar cutaneous branch of the ulnar.
Clinical significance
Unlike most of the median nerve innervation of the hand, the palmar branch travels superficial to the Flexor retinaculum of the hand. Therefore, this portion of the median nerve usually remains functioning during carpal tunnel syndrome.
Additional images
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https://en.wikipedia.org/wiki/Bending%20moment
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In solid mechanics, a bending moment is the reaction induced in a structural element when an external force or moment is applied to the element, causing the element to bend. The most common or simplest structural element subjected to bending moments is the beam. The diagram shows a beam which is simply supported (free to rotate and therefore lacking bending moments) at both ends; the ends can only react to the shear loads. Other beams can have both ends fixed (known as encastre beam); therefore each end support has both bending moments and shear reaction loads. Beams can also have one end fixed and one end simply supported. The simplest type of beam is the cantilever, which is fixed at one end and is free at the other end (neither simple or fixed). In reality, beam supports are usually neither absolutely fixed nor absolutely rotating freely.
The internal reaction loads in a cross-section of the structural element can be resolved into a resultant force and a resultant couple. For equilibrium, the moment created by external forces/moments must be balanced by the couple induced by the internal loads. The resultant internal couple is called the bending moment while the resultant internal force is called the shear force (if it is transverse to the plane of element) or the normal force (if it is along the plane of the element). Normal force is also termed as axial force.
The bending moment at a section through a structural element may be defined as the sum of the moments about that section of all external forces acting to one side of that section. The forces and moments on either side of the section must be equal in order to counteract each other and maintain a state of equilibrium so the same bending moment will result from summing the moments, regardless of which side of the section is selected. If clockwise bending moments are taken as negative, then a negative bending moment within an element will cause "hogging", and a positive moment will cause "sagging". It is
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https://en.wikipedia.org/wiki/Form%20factor%20%28quantum%20field%20theory%29
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In elementary particle physics and mathematical physics, in particular in effective field theory, a form factor is a function that encapsulates the properties of a certain particle interaction without including all of the underlying physics, but instead, providing the momentum dependence of suitable matrix elements. It is further measured experimentally in confirmation or specification of a theory—see experimental particle physics.
Photon–nucleon example
For example, at low energies the interaction of a photon with a nucleon is a very complicated calculation involving interactions between the photon and a sea of quarks and gluons, and often the calculation cannot be fully performed from first principles. Often in this context, form factors are also called "structure functions", since they can be used to describe the structure of the nucleon.
However, the generic Lorentz-invariant form of the matrix element for the electromagnetic current interaction is known,
where represents the photon momentum (equal in magnitude to E/c, where E is the energy of the photon). The three functions: are associated to the electric and magnetic form factors for this interaction, and are routinely measured experimentally; these three effective vertices can then be used to check, or perform calculations that would otherwise be too difficult to perform from first principles. This matrix element then serves to determine the transition amplitude involved in the scattering interaction or the respective particle decay—cf. Fermi's golden rule.
In general, the Fourier transforms of form factor components correspond to electric charge or magnetic profile space distributions (such as the charge radius) of the hadron involved. The analogous QCD structure functions are a probe of the quark and gluon distributions of nucleons.
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https://en.wikipedia.org/wiki/ISO%2022000
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ISO 22000 is a food safety management system by the International Organization for Standardization (ISO) which is outcome focused, providing requirements for any organization in the food industry with objective to help to improve overall performance in food safety. These standards are intended to ensure safety in the global food supply chain. The standards involve the overall guidelines for food safety management and also focuses on traceability in the feed and food chain.
Food safety
Food safety refers to all those hazards, whether chronic or acute, that may make food injurious to the health of the consumer.
ISO 22000 standard
ISO 22000 is the most popular voluntary food safety international standard in the food industry with 51,535 total number of sites (as per the ISO Survey 2022). The ISO 22000 family are international voluntary consensus standards which align to Good Standardization Practices (GSP) and the World Trade Organization (WTO) Principles for the Development of International Standards. Defining the requirements for a Food Safety Management System (FSMS) and incorporating the following elements which as defined as FSMS principles:
interactive communication
system management
prerequisite programs
HACCP principles
Critical reviews of the above elements have been conducted by many scientists. Communication along the food chain is essential to ensure that all relevant food safety hazards are identified and adequately controlled at each step within the food chain. This implies communication between organizations both upstream and downstream in the food chain. Communication with customers and suppliers about identified hazards and control measures will assist in clarifying customer and supplier requirements.
Recognition of the organization's role and position within the food chain is essential to ensure effective interactive communication throughout the chain in order to deliver safe food products to the consumer.
ISO 22000 and HACCP
ISO 22000 has
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https://en.wikipedia.org/wiki/Layer%20%28object-oriented%20design%29
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In software object-oriented design, a layer is a group of classes that have the same set of link-time module dependencies to other modules. In other words, a layer is a group of reusable components that are reusable in similar circumstances. In programming languages, the layer distinction is often expressed as "import" dependencies between software modules.
Layers are often arranged in a tree-form hierarchy, with dependency relationships as links between the layers. Dependency relationships between layers are often either inheritance, composition or aggregation relationships, but other kinds of dependencies can also be used.
Layers is an architectural pattern described in many books, for example Pattern-Oriented Software Architecture
See also
Abstraction layer
Multitier architecture
Shearing layers
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https://en.wikipedia.org/wiki/FLP-FRT%20recombination
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In genetics, Flp-FRT recombination is a site-directed recombination technology, increasingly used to manipulate an organism's DNA under controlled conditions in vivo. It is analogous to Cre-lox recombination but involves the recombination of sequences between short flippase recognition target (FRT) sites by the recombinase flippase (Flp) derived from the 2 µ plasmid of baker's yeast Saccharomyces cerevisiae.
The 34bp minimal FRT site sequence has the sequence
5'3'
for which flippase (Flp) binds to both 13-bp 5'-GAAGTTCCTATTC-3' arms flanking the 8 bp spacer, i.e. the site-specific recombination (region of crossover) in reverse orientation. FRT-mediated cleavage occurs just ahead from the asymmetric 8bp core region (5'3') on the top strand and behind this sequence on the bottom strand. Several variant FRT sites exist, but recombination can usually occur only between two identical FRTs but generally not among non-identical ("heterospecific") FRTs.
Biological function
In yeast, this enzyme corrects decreases in 2 µ plasmid copy number caused by rare missegregation events. It does so by causing recombination between the two inverted repetitions on the 2 µ plasmid during DNA replication. This changes the direction of one replication fork, causing multiple rounds of copying in a single initiation.
Mutations of the FRT site sequence
Senecoff et al. (1987) investigated how nucleotide substitutions within the FRT affected the efficacy of the FLP-mediated recombination. The authors induced base substitutions in either one or both of the FRT sites and tested the concentration of FLP required to observe site-specific recombinations. Every base substitution was performed on each of the thirteen nucleotides within the FRT site (example G to A, T, and C). First, the authors showed that most mutations within the FRT sequence cause minimal effects if present within only one of the two sites. If mutations occurred within both sites, the efficiency of FLP is dramatically reduc
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https://en.wikipedia.org/wiki/Class%20formation
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In mathematics, a class formation is a topological group acting on a module satisfying certain conditions. Class formations were introduced by Emil Artin and John Tate to organize the various Galois groups and modules that appear in class field theory.
Definitions
A formation is a topological group G together with a topological G-module A on which G acts continuously.
A layer E/F of a formation is a pair of open subgroups E, F of G such that F is a finite index subgroup of E. It is called a normal layer if
F is a normal subgroup of E, and a cyclic layer if in addition the quotient group is cyclic.
If E is a subgroup of G, then AE is defined to be the elements of A fixed by E.
We write
Hn(E/F)
for the Tate cohomology group
Hn(E/F, AF) whenever E/F is a normal layer. (Some authors think of E and F as fixed fields rather than subgroup of G, so write F/E instead of E/F.)
In applications, G is often the absolute Galois group of a field, and in particular is profinite, and the open subgroups therefore correspond to the finite extensions of the field contained in some fixed separable closure.
A class formation is a formation
such that for every normal layer E/F
H1(E/F) is trivial, and
H2(E/F) is cyclic of order |E/F|.
In practice, these cyclic groups come provided with canonical generators uE/F ∈ H2(E/F),
called fundamental classes, that are compatible with each other in the sense that
the restriction (of cohomology classes) of a fundamental class is another fundamental class.
Often the fundamental classes are considered to be part of the structure of a class formation.
A formation that satisfies just the condition H1(E/F)=1 is sometimes called a field formation.
For example, if G is any finite group acting on a field L and A=L×, then this is a field formation by Hilbert's theorem 90.
Examples
The most important examples of class formations (arranged roughly in order of difficulty) are as follows:
Archimedean local class field theory: The module A is the group of
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https://en.wikipedia.org/wiki/Apoptosis%20regulator%20BAX
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Apoptosis regulator BAX, also known as bcl-2-like protein 4, is a protein that in humans is encoded by the BAX gene. BAX is a member of the Bcl-2 gene family. BCL2 family members form hetero- or homodimers and act as anti- or pro-apoptotic regulators that are involved in a wide variety of cellular activities. This protein forms a heterodimer with BCL2, and functions as an apoptotic activator. This protein is reported to interact with, and increase the opening of, the mitochondrial voltage-dependent anion channel (VDAC), which leads to the loss in membrane potential and the release of cytochrome c. The expression of this gene is regulated by the tumor suppressor P53 and has been shown to be involved in P53-mediated apoptosis.
Structure
The BAX gene was the first identified pro-apoptotic member of the Bcl-2 protein family. Bcl-2 family members share one or more of the four characteristic domains of homology entitled the Bcl-2 homology (BH) domains (named BH1, BH2, BH3 and BH4), and can form hetero- or homodimers. These domains are composed of nine α-helices, with a hydrophobic α-helix core surrounded by amphipathic helices and a transmembrane C-terminal α-helix anchored to the mitochondrial outer membrane (MOM). A hydrophobic groove formed along the C-terminal of α2 to the N-terminal of α5, and some residues from α8, binds the BH3 domain of other BAX or BCL-2 proteins in its active form. In the protein's inactive form, the groove binds its transmembrane domain, transitioning it from a membrane-bound to a cytosolic protein. A smaller hydrophobic groove formed by the α1 and α6 helices is located on the opposite side of the protein from the major groove, and may serve as a BAX activation site.
Orthologs of the BAX gene have been identified in most mammals for which complete genome data are available.
Function
In healthy mammalian cells, the majority of BAX is found in the cytosol, but upon initiation of apoptotic signaling, Bax undergoes a conformational shift. U
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https://en.wikipedia.org/wiki/Operational%20transconductance%20amplifier
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The operational transconductance amplifier (OTA) is an amplifier whose differential input voltage produces an output current. Thus, it is a voltage controlled current source (VCCS). There is usually an additional input for a current to control the amplifier's transconductance. The OTA is similar to a standard operational amplifier in that it has a high impedance differential input stage and that it may be used with negative feedback.
The first commercially available integrated circuit units were produced by RCA in 1969 (before being acquired by General Electric) in the form of the CA3080. Although most units are constructed with bipolar transistors, field effect transistor units are also produced. The OTA is not as useful by itself in the vast majority of standard op-amp functions as the ordinary op-amp because its output is a current. One of its principal uses is in implementing electronically controlled applications such as variable frequency oscillators and filters and variable gain amplifier stages which are more difficult to implement with standard op-amps.
Principal differences from standard operational amplifiers
Its output of a current contrasts to that of standard operational amplifier whose output is a voltage.
It is usually used "open-loop"; without negative feedback in linear applications. This is possible because the magnitude of the resistance attached to its output controls its output voltage. Therefore, a resistance can be chosen that keeps the output from going into saturation, even with high differential input voltages.
Basic operation
In the ideal OTA, the output current is a linear function of the differential input voltage, calculated as follows:
where Vin+ is the voltage at the non-inverting input, Vin− is the voltage at the inverting input and gm is the transconductance of the amplifier.
The amplifier's output voltage is the product of its output current and its load resistance:
The voltage gain is then the output voltage divided b
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https://en.wikipedia.org/wiki/Hannay%20angle
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In classical mechanics, the Hannay angle is a mechanics analogue of the whirling geometric phase (or Berry phase). It was named after John Hannay of the University of Bristol, UK. Hannay first described the angle in 1985, extending the ideas of the recently formalized Berry phase to classical mechanics.
Hannay angle in classical mechanics
The Hannay angle is defined in the context of action-angle coordinates. In an initially time-invariant system, an action variable is a constant. After introducing a periodic perturbation , the action variable becomes an adiabatic invariant, and the Hannay angle for its corresponding angle variable can be calculated according to the path integral that represents an evolution in which the perturbation gets back to the original value
where and are canonical variables of the Hamiltonian.
Example
The Foucault pendulum is an example from classical mechanics that is sometimes also used to illustrate the Berry phase. Below we study the Foucault pendulum using action-angle variables. For simplicity, we will avoid using the Hamilton-Jacobi equation, which is employed in the general protocol.
We consider a plane pendulum with frequency under the effect of Earth's rotation whose angular velocity is with amplitude denoted as . Here, the direction points from the center of the Earth to the pendulum. The Lagrangian for the pendulum is
The corresponding motion equation is
We then introduce an auxiliary variable that is in fact an angle variable. We now have an equation for :
From its characteristic equation
we obtain its characteristic root (we note that )
The solution is then
After the Earth rotates one full rotation that is , we have the phase change for
The first term is due to dynamic effect of the pendulum and is termed as the dynamic phase, while the second term representing a geometric phase that is essentially the Hannay angle
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https://en.wikipedia.org/wiki/Contact%20inhibition
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In cell biology, contact inhibition refers to two different but closely related phenomena: contact inhibition of locomotion (CIL) and contact inhibition of proliferation (CIP). CIL refers to the avoidance behavior exhibited by fibroblast-like cells when in contact with one another. In most cases, when two cells contact each other, they attempt to alter their locomotion in a different direction to avoid future collision. When collision is unavoidable, a different phenomenon occurs whereby growth of the cells of the culture itself eventually stops in a cell-density dependent manner. Both types of contact inhibition are well-known properties of normal cells and contribute to the regulation of proper tissue growth, differentiation, and development. It is worth noting that both types of regulation are normally negated and overcome during organogenesis during embryonic development and tissue and wound healing. However, contact inhibition of locomotion and proliferation are both aberrantly absent in cancer cells, and the absence of this regulation contributes to tumorigenesis.
Mechanism
Contact inhibition is a regulatory mechanism that functions to keep cells growing into a layer one cell thick (a monolayer). If a cell has plenty of available substrate space, it replicates rapidly and moves freely. This process continues until the cells occupy the entire substratum. At this point, normal cells will stop replicating.
As motile cells come into contact in confluent cultures, they exhibit decreased mobility and mitotic activity over time. Exponential growth has been shown to occur between colonies in contact for numerous days, with the inhibition of mitotic activity occurring far later. This delay between cell-cell contact and onset of proliferation inhibition is shortened as the culture becomes more confluent. Thus, it may be reasonably concluded that cell-cell contact is an essential condition for contact inhibition of proliferation, but is by itself insufficient for mit
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https://en.wikipedia.org/wiki/Istv%C3%A1n%20Hatvani
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István Hatvani (1718–1786) was a Hungarian mathematician. He worked on developing some of the earliest elements of probability theory.
External links
Biography at University of St Andrews, Scotland
1718 births
1786 deaths
18th-century Hungarian mathematicians
Probability theorists
Istvan
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https://en.wikipedia.org/wiki/August%20Adler
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August Adler (24 January 1863, Opava, Austrian Silesia – 17 October 1923, Vienna) was a Czech and Austrian mathematician noted for using the theory of inversion to provide an alternate proof of Mascheroni's compass and straightedge construction theorem.
External links
1863 births
1923 deaths
People from Opava
People from Austrian Silesia
Geometers
19th-century Austrian mathematicians
Czechoslovak mathematicians
Mathematicians from Austria-Hungary
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https://en.wikipedia.org/wiki/Palindromic%20sequence
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A palindromic sequence is a nucleic acid sequence in a double-stranded DNA or RNA molecule whereby reading in a certain direction (e.g. 5' to 3') on one strand is identical to the sequence in the same direction (e.g. 5' to 3') on the complementary strand. This definition of palindrome thus depends on complementary strands being palindromic of each other.
The meaning of palindrome in the context of genetics is slightly different from the definition used for words and sentences. Since a double helix is formed by two paired antiparallel strands of nucleotides that run in opposite directions, and the nucleotides always pair in the same way (adenine (A) with thymine (T) in DNA or uracil (U) in RNA; cytosine (C) with guanine (G)), a (single-stranded) nucleotide sequence is said to be a palindrome if it is equal to its reverse complement. For example, the DNA sequence ACCTAGGT is palindromic with its nucleotide-by-nucleotide complement TGGATCCA because reversing the order of the nucleotides in the complement gives the original sequence.
A palindromic nucleotide sequence is capable of forming a hairpin. The stem portion of the hairpin is a pseudo-double stranded portion since the entire hairpin is a part of same (single) strand of nucleic acid. Palindromic motifs are found in most genomes or sets of genetic instructions. They have been specially researched in bacterial chromosomes and in the so-called Bacterial Interspersed Mosaic Elements (BIMEs) scattered over them. In 2008, a genome sequencing project discovered that large portions of the human X and Y chromosomes are arranged as palindromes. A palindromic structure allows the Y chromosome to repair itself by bending over at the middle if one side is damaged.
Palindromes also appear to be found frequently in the peptide sequences that make up proteins, but their role in protein function is not clearly known. It has been suggested that the existence of palindromes in peptides might be related to the prevalence of l
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https://en.wikipedia.org/wiki/Shotgun%20lipidomics
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In lipidomics, the process of shotgun lipidomics (named by analogy with shotgun sequencing) uses analytical chemistry to investigate the biological function, significance, and sequelae of alterations in lipids and protein constituents mediating lipid metabolism, trafficking, or biological function in cells.
Lipidomics has been greatly facilitated by recent advances in, and novel applications of, electrospray ionization mass spectrometry (ESI/MS).
Lipidomics is a research field that studies the pathways and networks of cellular lipids in biological systems (i.e., lipidomes) on a large scale. It involves the identification and quantification of the thousands of cellular lipid molecular species and their interactions with other lipids, proteins, and other moieties in vivo. Investigators in lipidomics examine the structures, functions, interactions, and dynamics of cellular lipids and the dynamic changes that occur during pathophysiologic perturbations. Lipidomic studies play an essential role in defining the biochemical mechanisms of lipid-related disease processes through identifying alterations in cellular lipid metabolism, trafficking and homeostasis. The two major platforms currently used for lipidomic analyses are HPLC-MS and shotgun lipidomics.
History
Shotgun lipidomics was developed by Richard W. Gross and Xianlin Han, by employing ESI intrasource separation techniques. Individual molecular species of most major and many minor lipid classes can be fingerprinted and quantitated directly from biological lipid extracts without the need for chromatographic purification.
Advantages
Shotgun lipidomics is fast, highly sensitive, and it can identify hundreds of lipids missed by other methods — all with a much smaller tissue sample so that specific cells or minute biopsy samples can be examined.
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https://en.wikipedia.org/wiki/Deterministic%20acyclic%20finite%20state%20automaton
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In computer science, a deterministic acyclic finite state automaton (DAFSA),
also called a directed acyclic word graph (DAWG; though that name also refers to a related data structure that functions as a suffix index)
is a data structure that represents a set of strings, and allows for a query operation that tests whether a given string belongs to the set in time proportional to its length. Algorithms exist to construct and maintain such automata, while keeping them minimal.
A DAFSA is a special case of a finite state recognizer that takes the form of a directed acyclic graph with a single source vertex (a vertex with no incoming edges), in which each edge of the graph is labeled by a letter or symbol, and in which each vertex has at most one outgoing edge for each possible letter or symbol. The strings represented by the DAFSA are formed by the symbols on paths in the graph from the source vertex to any sink vertex (a vertex with no outgoing edges). In fact, a deterministic finite state automaton is acyclic if and only if it recognizes a finite set of strings.
Comparison to tries
By allowing the same vertices to be reached by multiple paths, a DAFSA may use significantly fewer vertices than the strongly related trie data structure. Consider, for example, the four English words "tap", "taps", "top", and "tops". A trie for those four words would have 12 vertices, one for each of the strings formed as a prefix of one of these words, or for one of the words followed by the end-of-string marker. However, a DAFSA can represent these same four words using only six vertices vi for 0 ≤ i ≤ 5, and the following edges: an edge from v0 to v1 labeled "t", two edges from v1 to v2 labeled "a" and "o", an edge from v2 to v3 labeled "p", an edge v3 to v4 labeled "s", and edges from v3 and v4 to v5 labeled with the end-of-string marker. There is a tradeoff between memory and functionality, because a standard DAFSA can tell you if a word exists within it, but it cannot point you to
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https://en.wikipedia.org/wiki/Plant%20cuticle
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A plant cuticle is a protecting film covering the outermost skin layer (epidermis) of leaves, young shoots and other aerial plant organs (aerial here meaning all plant parts not embedded in soil or other substrate) that have no periderm. The film consists of lipid and hydrocarbon polymers infused with wax, and is synthesized exclusively by the epidermal cells.
Description
The plant cuticle is a layer of lipid polymers impregnated with waxes that is present on the outer surfaces of the primary organs of all vascular land plants. It is also present in the sporophyte generation of hornworts, and in both sporophyte and gametophyte generations of mosses The plant cuticle forms a coherent outer covering of the plant that can be isolated intact by treating plant tissue with enzymes such as pectinase and cellulase.
Composition
The cuticle is composed of an insoluble cuticular membrane impregnated by and covered with soluble waxes. Cutin, a polyester polymer composed of inter-esterified omega hydroxy acids which are cross-linked by ester and epoxide bonds, is the best-known structural component of the cuticular membrane. The cuticle can also contain a non-saponifiable hydrocarbon polymer known as Cutan. The cuticular membrane is impregnated with cuticular waxes and covered with epicuticular waxes, which are mixtures of hydrophobic aliphatic compounds, hydrocarbons with chain lengths typically in the range C16 to C36.
Cuticular wax biosynthesis
Cuticular wax is known to be largely composed of compounds which derive from very-long-chain fatty acids (VLCFAs), such as aldehydes, alcohols, alkanes, ketones, and esters. Also present are other compounds in cuticular wax which are not VLCFA derivatives, such as terpenoids, flavonoids, and sterols, and thus have different synthetic pathways than those VLCFAs.
The first step of the biosynthesis pathway for the formation of cuticular VLCFAs, occurs with the de novo biosynthesis of C16 acyl chains (palmitate) by chloroplasts in t
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https://en.wikipedia.org/wiki/Pieter%20Hendrik%20Schoute
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Pieter Hendrik Schoute (21 January 1846, Wormerveer – 18 April 1913, Groningen) was a Dutch mathematician known for his work on regular polytopes and Euclidean geometry.
He started his career as a civil engineer, but became a professor of mathematics at Groningen and published some thirty papers on polytopes between 1878 and his death in 1913. He collaborated with Alicia Boole Stott on describing the sections of the regular 4-polytopes.
In 1886, he became member of the Royal Netherlands Academy of Arts and Sciences.
Citations
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https://en.wikipedia.org/wiki/Hendrik%20Kloosterman
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Hendrik Douwe Kloosterman (9 April 1900 – 6 May 1968) was a Dutch mathematician, known for his work in number theory (in particular, for introducing Kloosterman sums) and in representation theory.
After completing his master's degree at Leiden University from 1918–1922 he studied at the University of Copenhagen with Harald Bohr and the University of Oxford with G. H. Hardy. In 1924 he received his Ph.D. in Leiden under the supervision of J. C. Kluyver. From 1926 to 1928 he studied at the Universities of Göttingen and Hamburg, and he was an assistant at the University of Münster from 1928-1930. Kloosterman was appointed lector (associate professorship) at Leiden University in 1930 and full professor in 1947. In 1950 he was elected a member of the Royal Netherlands Academy of Arts and Sciences.
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https://en.wikipedia.org/wiki/List%20of%20phylogenetics%20software
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This list of phylogenetics software is a compilation of computational phylogenetics software used to produce phylogenetic trees. Such tools are commonly used in comparative genomics, cladistics, and bioinformatics. Methods for estimating phylogenies include neighbor-joining, maximum parsimony (also simply referred to as parsimony), UPGMA, Bayesian phylogenetic inference, maximum likelihood and distance matrix methods.
List
See also
List of phylogenetic tree visualization software
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https://en.wikipedia.org/wiki/DAML-S
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The DARPA agent markup language for services (DAML-S) is a semantic markup language for describing web services and related ontologies.
DAML-S is built on top of DAML+OIL.
DAML-S has been superseded by OWL-S
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https://en.wikipedia.org/wiki/Wilmagate
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WilmaGate is a collection of open-source tools for Authentication, Authorization and Accounting on an Open Access Network. It has been initially developed by the Computer Networks and Mobility Group at the University of Trento (Italy).
Its development has been part of the locally funded Wilma Project and is now being pursued by the Twelve Project under the name Uni-Fy. It is currently being used for wireless authentication at the Faculty of Science at the University of Trento and by the UniWireless network of Italian research groups participating in the Twelve Project.
Features
The system has been designed in order to separate the user authentication phase (which is usually performed by a possibly remote ISP) from internet access provided at the user's current location by a local carrier.
Therefore, a multiplicity of authentication providers and of access providers is envisioned. The WilmaGate system provides code for both purposes and for a variety of authentication methods. Its modular and object-oriented structure allows programmers to easily add plug-in code for new authentication or accounting protocols. See this article for details.
Steps
The following steps are performed in a normal user connection.
The user's mobile terminal (laptop or PDA) physically connects to a network, either by plugging in a cable (Ethernet or FireWire) or by associating with a wireless access point via Wi-Fi or Bluetooth.
The terminal automatically issues a DHCP handshake in order to set up an appropriate configuration for the network it is entering. By this action, the mobile terminal's existence is recognized by the Gateway component.
The client starts some form of authentication process, either by opening a web browser and having it redirected to an authentication provider of the admin's choice, or through some pre-installed authentication program.
After authentication the client has possibly full Internet access; however, some authentication-based restrictions are ap
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https://en.wikipedia.org/wiki/Rocks%20Cluster%20Distribution
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Rocks Cluster Distribution (originally NPACI Rocks) is a Linux distribution intended for high-performance computing (HPC) clusters. It was started by National Partnership for Advanced Computational Infrastructure and the San Diego Supercomputer Center (SDSC) in 2000. It was initially funded in part by an NSF grant (2000–07), but was funded by the follow-up NSF grant through 2011.
Distribution
Rocks was initially based on the Red Hat Linux (RHL) distribution, however modern versions of Rocks were based on CentOS, with a modified Anaconda installer that simplifies mass installation onto many computers. Rocks includes many tools (such as Message Passing Interface (MPI)) which are not part of CentOS but are integral components that make a group of computers into a cluster.
Installations can be customized with additional software packages at install-time by using special user-supplied CDs (called "Roll CDs"). The "Rolls" extend the system by integrating seamlessly and automatically into the management and packaging mechanisms used by base software, greatly simplifying installation and configuration of large numbers of computers. Over a dozen Rolls have been created, including the Sun Grid Engine (SGE) roll, the Condor roll, the Lustre roll, the Java roll, and the Ganglia roll.
By October 2010, Rocks was used for academic, government, and commercial organizations, employed in 1,376 clusters, on every continent except Antarctica. The largest registered academic cluster, having 8632 CPUs, is GridKa, operated by the Karlsruhe Institute of Technology in Karlsruhe, Germany. There are also a number of clusters ranging down to fewer than 10 CPUs, representing the early stages in the construction of larger systems, as well as being used for courses in cluster design. This easy scalability was a major goal in the development of Rocks, both for the researchers involved, and for the NSF:
Release history
See also
Scientific Linux – a Linux distribution by Fermilab and CERN
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https://en.wikipedia.org/wiki/Metamath
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Metamath is a formal language and an associated computer program (a proof assistant) for archiving and verifying mathematical proofs. Several databases of proved theorems have been developed using Metamath covering standard results in logic, set theory, number theory, algebra, topology and analysis, among others.
, the set of proved theorems using Metamath includes 74 of the 100 theorems of the "Formalizing 100 Theorems" challenge, making it fifth after Isabelle, HOL Light, Coq, and Lean.
There are at least 19 proof verifiers that use the Metamath format.
The Metamath website provides a database of formalized theorems which can be browsed interactively.
Metamath language
The Metamath language is a metalanguage for formal systems. The Metamath language has no specific logic embedded in it. Instead, it can be regarded as a way to prove that inference rules (asserted as axioms or proven later) can be applied.
The largest database of proved theorems follows conventional first-order logic and ZFC set theory.
The Metamath language design (employed to state the definitions, axioms, inference rules and theorems) is focused on simplicity; it contains only a handful of keywords. Proofs are checked using an algorithm based on variable substitution. The algorithm also has optional provisos for what variables must remain distinct after a substitution is made.
Language basics
The set of symbols that can be used for constructing formulas is declared using $c (constant symbols) and $v (variable symbols) statements; for example:
$( Declare the constant symbols we will use $)
$c 0 + = -> ( ) term wff |- $.
$( Declare the metavariables we will use $)
$v t r s P Q $.
The grammar for formulas is specified using a combination of $f (floating (variable-type)
hypotheses) and $a (axiomatic assertion) statements; for example:
$( Specify properties of the metavariables $)
tt $f term t $.
tr $f term r $.
ts $f term s $.
wp $f wff P $.
wq $f wff Q $.
$( Defin
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https://en.wikipedia.org/wiki/Graves%27%20ophthalmopathy
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Graves’ ophthalmopathy, also known as thyroid eye disease (TED), is an autoimmune inflammatory disorder of the orbit and periorbital tissues, characterized by upper eyelid retraction, lid lag, swelling, redness (erythema), conjunctivitis, and bulging eyes (exophthalmos). It occurs most commonly in individuals with Graves' disease, and less commonly in individuals with Hashimoto's thyroiditis, or in those who are euthyroid.
It is part of a systemic process with variable expression in the eyes, thyroid, and skin, caused by autoantibodies that bind to tissues in those organs. The autoantibodies target the fibroblasts in the eye muscles, and those fibroblasts can differentiate into fat cells (adipocytes). Fat cells and muscles expand and become inflamed. Veins become compressed and are unable to drain fluid, causing edema.
Annual incidence is 16/100,000 in women, 3/100,000 in men. About 3–5% have severe disease with intense pain, and sight-threatening corneal ulceration or compression of the optic nerve. Cigarette smoking, which is associated with many autoimmune diseases, raises the incidence 7.7-fold.
Mild disease will often resolve and merely requires measures to reduce discomfort and dryness, such as artificial tears and smoking cessation if possible. Severe cases are a medical emergency, and are treated with glucocorticoids (steroids), and sometimes ciclosporin. Many anti-inflammatory biological mediators, such as infliximab, etanercept, and anakinra are being tried. In January 2020, the US Food and Drug Administration approved teprotumumab-trbw for the treatment of Graves’ ophthalmopathy.
Signs and symptoms
In mild disease, patients present with eyelid retraction. In fact, upper eyelid retraction is the most common ocular sign of Graves' orbitopathy. This finding is associated with lid lag on infraduction (Von Graefe's sign), eye globe lag on supraduction (Kocher's sign), a widened palpebral fissure during fixation (Dalrymple's sign) and an incapacity of clos
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https://en.wikipedia.org/wiki/Star%20polygons%20in%20art%20and%20culture
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Star polygons and polygonal compounds are the basis for numerous figures of significance in arts and culture. The figure may be the border or interior of the polygon, or one or more closed polygonal paths that include all of the border and also have some legs crossing the interior. The name is derived from the polygon's similarity to the diffraction spikes of astronomical stars, but specific uses may exploit the connection or not. Stars often represent the unity of states within a country when they are used as a part of the flag.
Emblematic use
In heraldry, a mullet is a star with straight arms and typically five points. A star with wavy rather than straight rays is called an estoile. The mullet, used as an heraldic charge, is the ensign of knightly rank, and every order of knighthood incorporates this symbol in some way. It has traditionally been used in British heraldry as a mark of cadency for the third son.
In Christian art, St. Bruno bears a star on his breast; Saint Dominic, Saint Humbert and Saint Peter of Alcantara have a star on their head or forehead.
The star with six (or less commonly five, sometimes seven) points is associated with law enforcement in the United States, and forms the basis of the sheriff's badge.
Five-pointed stars
The five-pointed star, if drawn with points of equal length and angles of 36° at each point, is sometimes termed a golden five pointed star. If the colinear edges are joined, a pentagram is produced, which is the simplest of the unicursal star polygons, and a symbol of mystical and magical significance.
The golden five-pointed star is a very common ideogram in the western world, and has particularly strong associations with military power and war. Many communist countries (such as China and Vietnam) and symbols (the hammer and sickle) also incorporate five-pointed stars.
The five-pointed star appears in the flags of 35 countries, and also appears commonly in the heraldry of the United States, and stands in contrast to the
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https://en.wikipedia.org/wiki/Groundwater%20recharge
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Groundwater recharge or deep drainage or deep percolation is a hydrologic process, where water moves downward from surface water to groundwater. Recharge is the primary method through which water enters an aquifer. This process usually occurs in the vadose zone below plant roots and is often expressed as a flux to the water table surface. Groundwater recharge also encompasses water moving away from the water table farther into the saturated zone. Recharge occurs both naturally (through the water cycle) and through anthropogenic processes (i.e., "artificial groundwater recharge"), where rainwater and or reclaimed water is routed to the subsurface.
The most common methods to estimate recharge rates are: chloride mass balance (CMB); soil physics methods; environmental and isotopic tracers; groundwater-level fluctuation methods; water balance (WB) methods (including groundwater models (GMs)); and the estimation of baseflow (BF) to rivers.
Processes
Diffused or focused mechanisms
Groundwater recharge can occur through diffuse or focused mechanisms. Diffuse recharge occurs when precipitation infiltrates through the soil to the water table, and is by definition distributed over large areas. Focussed recharge occurs where water leaks from surface water sources (rivers, lakes, wadis, wetlands) or land surface depressions, and generally becomes more dominant with aridity.
Natural recharge
Water is recharged naturally by rain and snow melt and to a smaller extent by surface water (rivers and lakes). Recharge may be impeded somewhat by human activities including paving, development, or logging. These activities can result in loss of topsoil resulting in reduced water infiltration, enhanced surface runoff and reduction in recharge. Use of groundwater, especially for irrigation, may also lower the water tables. Groundwater recharge is an important process for sustainable groundwater management, since the volume-rate abstracted from an aquifer in the long term should be le
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https://en.wikipedia.org/wiki/Persistence%20%28computer%20science%29
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In computer science, persistence refers to the characteristic of state of a system that outlives (persists more than) the process that created it. This is achieved in practice by storing the state as data in computer data storage. Programs have to transfer data to and from storage devices and have to provide mappings from the native programming-language data structures to the storage device data structures.
Picture editing programs or word processors, for example, achieve state persistence by saving their documents to files.
Orthogonal or transparent persistence
Persistence is said to be "orthogonal" or "transparent" when it is implemented as an intrinsic property of the execution environment of a program. An orthogonal persistence environment does not require any specific actions by programs running in it to retrieve or save their state.
Non-orthogonal persistence requires data to be written and read to and from storage using specific instructions in a program, resulting in the use of persist as a transitive verb: On completion, the program persists the data.
The advantage of orthogonal persistence environments is simpler and less error-prone programs.
The term "persistent" was first introduced by Atkinson and Morrison in the sense of orthogonal persistence: they used an adjective rather than a verb to emphasize persistence as a property of the data, as distinct from an imperative action performed by a program. The use of the transitive verb "persist" (describing an action performed by a program) is a back-formation.
Adoption
Orthogonal persistence is widely adopted in operating systems for hibernation and in platform virtualization systems such as VMware and VirtualBox for state saving.
Research prototype languages such as PS-algol, Napier88, Fibonacci and pJama, successfully demonstrated the concepts along with the advantages to programmers.
Persistence techniques
System images
Using system images is the simplest persistence strategy. Notebook hibernati
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https://en.wikipedia.org/wiki/Plasma%20protein%20binding
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Plasma protein binding refers to the degree to which medications attach to blood proteins within the blood plasma. A drug's efficacy may be affected by the degree to which it binds. The less bound a drug is, the more efficiently it can traverse or diffuse through cell membranes. Common blood proteins that drugs bind to are human serum albumin, lipoprotein, glycoprotein, and α, β‚ and γ globulins.
Binding (drug distribution)
A drug in blood exists in two forms: bound and unbound. Depending on a specific drug's affinity for plasma proteins, a proportion of the drug may become bound to the proteins, with the remainder being unbound. If the protein binding is reversible, then a chemical equilibrium will exist between the bound and unbound states, such that:
Protein + drug ⇌ Protein-drug complex
Notably, it is the unbound fraction which exhibits pharmacologic effects. It is also the fraction that may be metabolized and/or excreted. For example, the "fraction bound" of the anticoagulant warfarin is 97%. This means that out of the amount of warfarin in the blood, 97% is bound to plasma proteins. The remaining 3% (the fraction unbound) is the fraction that is actually active and may be excreted.
Protein binding can influence the drug's biological half-life. The bound portion may act as a reservoir or depot from which the drug is slowly released as the unbound form. Since the unbound form is being metabolized and/or excreted from the body, the bound fraction will be released in order to maintain equilibrium.
Since albumin is alkalotic, acidic and neutral drugs will primarily bind to albumin. If albumin becomes saturated, then these drugs will bind to lipoprotein. Basic drugs will bind to the acidic alpha-1 acid glycoprotein. This is significant because various medical conditions may affect the levels of albumin, alpha-1 acid glycoprotein, and lipoproteins.
Impact of the altered protein binding
Only the unbound fraction of the drug undergoes metabolism in the liver a
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https://en.wikipedia.org/wiki/Weighted%20majority%20algorithm%20%28machine%20learning%29
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In machine learning, weighted majority algorithm (WMA) is a meta learning algorithm used to construct a compound algorithm from a pool of prediction algorithms, which could be any type of learning algorithms, classifiers, or even real human experts.
The algorithm assumes that we have no prior knowledge about the accuracy of the algorithms in the pool, but there are sufficient reasons to believe that one or more will perform well.
Assume that the problem is a binary decision problem. To construct the compound algorithm, a positive weight is given to each of the algorithms in the pool. The compound algorithm then collects weighted votes from all the algorithms in the pool, and gives the prediction that has a higher vote. If the compound algorithm makes a mistake, the algorithms in the pool that contributed to the wrong predicting will be discounted by a certain ratio β where 0<β<1.
It can be shown that the upper bounds on the number of mistakes made in a given sequence of predictions from a pool of algorithms is
if one algorithm in makes at most mistakes.
There are many variations of the weighted majority algorithm to handle different situations, like shifting targets, infinite pools, or randomized predictions. The core mechanism remains similar, with the final performances of the compound algorithm bounded by a function of the performance of the specialist (best performing algorithm) in the pool.
See also
Randomized weighted majority algorithm
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https://en.wikipedia.org/wiki/Axial%20symmetry
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Axial symmetry is symmetry around an axis; an object is axially symmetric if its appearance is unchanged if rotated around an axis. For example, a baseball bat without trademark or other design, or a plain white tea saucer, looks the same if it is rotated by any angle about the line passing lengthwise through its center, so it is axially symmetric.
Axial symmetry can also be discrete with a fixed angle of rotation, 360°/n for n-fold symmetry.
See also
Axiality (geometry)
Circular symmetry
Reflection symmetry
Rotational symmetry has a more general discussion
Chiral symmetry describes the use in quantum mechanics
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https://en.wikipedia.org/wiki/Monty%20Hall%20problem
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The Monty Hall problem is a brain teaser, in the form of a probability puzzle, loosely based on the American television game show Let's Make a Deal and named after its original host, Monty Hall. The problem was originally posed (and solved) in a letter by Steve Selvin to the American Statistician in 1975. It became famous as a question from reader Craig F. Whitaker's letter quoted in Marilyn vos Savant's "Ask Marilyn" column in Parade magazine in 1990:
Savant's response was that the contestant should switch to the other door. Under the standard assumptions, the switching strategy has a probability of winning the car, while the strategy of sticking with the initial choice has only a probability.
When the player first makes their choice, there is a chance that the car is behind one of the doors not chosen. This probability does not change after the host reveals a goat behind one of the unchosen doors. When the host provides information about the two unchosen doors (revealing that one of them does not have the car behind it), the chance of the car being behind one of the unchosen doors rests on the unchosen and unrevealed door, as opposed to the chance of the car being behind the door the contestant chose initially.
The given probabilities depend on specific assumptions about how the host and contestant choose their doors. A key insight is that, under these standard conditions, there is more information about doors 2 and 3 than was available at the beginning of the game when door 1 was chosen by the player: the host's action adds value to the door not eliminated, but not to the one chosen by the contestant originally. Another insight is that switching doors is a different action from choosing between the two remaining doors at random, as the former action uses the previous information and the latter does not. Other possible behaviors of the host than the one described can reveal different additional information, or none at all, and yield different probabilities
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https://en.wikipedia.org/wiki/Myogenesis
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Myogenesis is the formation of skeletal muscular tissue, particularly during embryonic development.
Muscle fibers generally form through the fusion of precursor myoblasts into multinucleated fibers called myotubes. In the early development of an embryo, myoblasts can either proliferate, or differentiate into a myotube. What controls this choice in vivo is generally unclear. If placed in cell culture, most myoblasts will proliferate if enough fibroblast growth factor (FGF) or another growth factor is present in the medium surrounding the cells. When the growth factor runs out, the myoblasts cease division and undergo terminal differentiation into myotubes. Myoblast differentiation proceeds in stages. The first stage, involves cell cycle exit and the commencement of expression of certain genes.
The second stage of differentiation involves the alignment of the myoblasts with one another. Studies have shown that even rat and chick myoblasts can recognise and align with one another, suggesting evolutionary conservation of the mechanisms involved.
The third stage is the actual cell fusion itself. In this stage, the presence of calcium ions is critical. Fusion in humans is aided by a set of metalloproteinases coded for by the ADAM12 gene, and a variety of other proteins. Fusion involves recruitment of actin to the plasma membrane, followed by close apposition and creation of a pore that subsequently rapidly widens.
Novel genes and their protein products that are expressed during the process are under active investigation in many laboratories. They include:
Myocyte enhancer factors (MEFs), which promote myogenesis.
Serum response factor (SRF) plays a central role during myogenesis, being required for the expression of striated alpha-actin genes. Expression of skeletal alpha-actin is also regulated by the androgen receptor; steroids can thereby regulate myogenesis.
Myogenic regulatory factors (MRFs): MyoD, Myf5, Myf6 and Myogenin.
Overview
There are a number o
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https://en.wikipedia.org/wiki/Noisy%20text%20analytics
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Noisy text analytics is a process of information extraction whose goal is to automatically extract structured or semistructured information from noisy unstructured text data. While Text analytics is a growing and mature field that has great value because of the huge amounts of data being produced, processing of noisy text is gaining in importance because a lot of common applications produce noisy text data. Noisy unstructured text data is found in informal settings such as online chat, text messages, e-mails, message boards, newsgroups, blogs, wikis and web pages. Also, text produced by processing spontaneous speech using automatic speech recognition and printed or handwritten text using optical character recognition contains processing noise. Text produced under such circumstances is typically highly noisy containing spelling errors, abbreviations, non-standard words, false starts, repetitions, missing punctuations, missing letter case information, pause filling words such as “um” and “uh” and other texting and speech disfluencies. Such text can be seen in large amounts in contact centers, chat rooms, optical character recognition (OCR) of text documents, short message service (SMS) text, etc. Documents with historical language can also be considered noisy with respect to today's knowledge about the language. Such text contains important historical, religious, ancient medical knowledge that is useful. The nature of the noisy text produced in all these contexts warrants moving beyond traditional text analysis techniques.
Techniques for noisy text analysis
Missing punctuation and the use of non-standard words can often hinder standard natural language processing tools such as part-of-speech tagging
and parsing. Techniques to both learn from the noisy data and then to be able to process the noisy data are only now being developed.
Possible source of noisy text
World Wide Web: Poorly written text is found in web pages, online chat, blogs, wikis, discussion forums,
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https://en.wikipedia.org/wiki/Phantasie%20II
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Phantasie II is the second game in the Phantasie series of role-playing video games.
Gameplay
In 1986, SSI published the next part of the Phantasie series, Phantasie II. Again, the Dark Lord Nikademus was the nemesis. This time Nikademus had fashioned an evil orb, and with it he cast a curse on a beautiful island named Ferronrah and enslaved its people. The player's mission was to find and destroy the orb.
Phantasie II used the same graphics and fighting as the original Phantasie game, with one improvement to combat: the ability of any character class to target any enemy rank with a thrown rock. There were improvements in the complexity of quests, but little was done to innovate the series. One option which endeared many veterans was the ability to transfer characters from Phantasie I to this sequel.
The manual included in Phantasie II was identical to the one included with Phantasie, plus a small card explaining the differences. Computer Gaming World noted this was advantageous in terms of how players of the original would have an easier time getting into the game, but disadvantageous as to some particularly tedious mechanisms of both games, particularly "the infamous Distribution and Selling rigamarole". The review continued to note that characters imported from the original have their equipment removed as well as most of their gold and experience, affording only a slight head start over newly created characters.
Reception
Phantasie II sold 30,100 copies. Compute! in 1986 recommended it to those seeking a more traditional role-playing game than SSI's Rings of Zilfin or who enjoyed Phantasie. Scorpia criticized Phantasie II for not changing its predecessor's "infamous Distribution and Selling rigamarole", including a bug with the handling of money. The magazine concluded that "although flawed in certain aspects, Phantasie II is an interesting, and overall good, game of the RPG type" and recommended it to fans of the first game. Reviewing the Atari ST version,
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https://en.wikipedia.org/wiki/Episcleritis
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Episcleritis is a benign, self-limiting inflammatory disease affecting part of the eye called the episclera. The episclera is a thin layer of tissue that lies between the conjunctiva and the connective tissue layer that forms the white of the eye (sclera). Episcleritis is a common condition, and is characterized by the abrupt onset of painless eye redness.
There are two types of episcleritis, nodular and simple. Nodular episcleritis lesions have raised surface. Simple episcleritis lesions are flat. There are two subtypes. In diffuse simple episcleritis, inflammation is generalized. In sectoral simple episcleritis, the inflammation is restricted to one region.
Most cases of episcleritis have no identifiable cause, although about a third of cases are associated with various systemic diseases. Often people with episcleritis experience it recurrently. Treatment focuses on decreasing discomfort, and includes lubricating eye drops. More severe cases may be treated with topical corticosteroids or oral anti-inflammatory medications (NSAIDs).
Signs and symptoms
Symptoms of episcleritis typically include painless redness of the eye (mild pain is possible but atypical), and watery eyes. The pain of episcleritis is typically mild, less severe than in scleritis, and may be tender to palpation.
There are two types of episcleritis: the diffuse type, where the redness involves the entire episclera, and the nodular type, where the redness appears more nodular, involving only a small, well-circumscribed area (sectoral). The diffuse type of episcleritis may be less painful than the nodular type. Sometimes, small nodules are present within the episclera, which move slightly over the sclera with gentle pressure.
Discharge is absent with episcleritis, and vision is unaffected. Patients with episcleritis experience far less photophobia than patients with uveitis. Episcleritis does not cause the presence of cells or flare in the anterior chamber of the eye. In 80 percent o
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https://en.wikipedia.org/wiki/Hammer%20and%20pick
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The hammer and pick, rarely referred to as hammer and chisel, is a symbol of mining, often used in heraldry. It can indicate mining, mines (especially on maps or in cartography), or miners, and is also borne as a charge in the coats of arms of mining towns.
The symbol represents the traditional tools of the miner, a hammer and a chisel on a handle, similar to a pickaxe, but with one blunt end. They are pictured in the way a right-handed worker would lay them down: the pick with the point to the right and the handle to the lower left, the hammer with the handle to the lower right and the head to the upper left. The handle of the pick protrudes over the head, because the head is not permanently fixed, but can be swapped for a newly sharpened head when it is blunt from use. In coats of arms the symbol is often shown in black (Johanngeorgenstadt, Hövels), but also in natural colours (Telnice) or in gold or silver (Abertamy, Bodenwöhr, Gelsenkirchen).
Examples
Other
The hammer and pick is used to indicate the working day, on timetables. As an emoji, it is often used as a symbol for fans of Premier League side West Ham United and for fans of Ukrainian Premier League club Shakhtar Donetsk.
Unicode
In Unicode, the "hammer and pick" symbol is U+2692 ⚒.
See also
Arm and hammer
Hammer and sickle
Political symbols
Heraldic charges
Mining culture and traditions
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https://en.wikipedia.org/wiki/Sexual%20dimorphism%20measures
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Although the subject of sexual dimorphism is not in itself controversial, the measures by which it is assessed differ widely. Most of the measures are used on the assumption that a random variable is considered so that probability distributions should be taken into account. In this review, a series of sexual dimorphism measures are discussed concerning both their definition and the probability law on which they are based. Most of them are sample functions, or statistics, which account for only partial characteristics, for example the mean or expected value, of the distribution involved. Further, the most widely used measure fails to incorporate an inferential support.
Introduction
It is widely known that sexual dimorphism is an important component of the morphological variation in biological populations (see, e.g., Klein and Cruz-Uribe, 1984; Oxnard, 1987; Kelley, 1993). In higher Primates, sexual dimorphism is also related to some aspects of the social organization and behavior (Alexander et al., 1979; Clutton-Brock, 1985). Thus, it has been observed that the most dimorphic species tend to polygyny and a social organization based on male dominance, whereas in the less dimorphic species, monogamy and family groups are more common. Fleagle et al. (1980) and Kay (1982), on the other hand, have suggested that the behavior of extinct species can be inferred on the basis of sexual dimorphism and, e.g. Plavcan and van Schaick (1992) think that sex differences in size among primate species reflect processes of an ecological and social nature. Some references on sexual dimorphism regarding human populations can be seen in Lovejoy (1981), Borgognini Tarli and Repetto (1986) and Kappelman (1996).
These biological facts do not appear to be controversial. However, they are based on a series of different sexual dimorphism measures, or indices. Sexual dimorphism, in most works, is measured on the assumption that a random variable is being taken into account. This means that th
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https://en.wikipedia.org/wiki/Open%20Hub
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Black Duck Open Hub, formerly Ohloh, is a website which provides a web services suite and online community platform that aims to index the open-source software development community. It was founded by former Microsoft managers Jason Allen and Scott Collison in 2004 and joined by the developer Robin Luckey. , the site lists 669,601 open-source projects, 681,345 source control repositories, 3,848,524 contributors and 31,688,426,179 lines of code.
In 2017, Black Duck Software (the company running the site) was acquired by Synopsys for $565 million.
History
Ohloh is a website that provides a web services suite and online community platform that aims to index the open-source software development community. It was founded by former Microsoft managers Jason Allen and Scott Collison in 2004 and joined by the developer Robin Luckey. , the site lists 669,601 open-source projects, 681,345 source control repositories, 3,848,524 contributors and 31,688,426,179 lines of code.
On 28 May 2009, Ohloh was acquired by Geeknet, owners of the popular open-source development platform SourceForge. However, Geeknet sold Ohloh to the open-source analysis company Black Duck Software on 5 October 2010. Black Duck integrated Ohloh's functionality with their existing products to advance the site into a major resource for FOSS development. On 18 July 2014, Ohloh became Black Duck Open Hub. In late August 2014, the Black Duck Open Hub's Organizations feature moved out of Beta and into Version 1.0.
Functionality and features
By retrieving data from revision control repositories (such as CVS, SVN, Git, Bazaar, and Mercurial), Black Duck Open Hub provides statistics about the longevity of projects, their licenses (including license conflict information) and software metrics such as source lines of code and commit statistics. The codebase history informs about the amount of activity for each project. Software stacks (list of software applications used by Black Duck Open Hub's members) and tags a
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https://en.wikipedia.org/wiki/Kendall%27s%20W
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Kendall's W (also known as Kendall's coefficient of concordance) is a non-parametric statistic for rank correlation. It is a normalization of the statistic of the Friedman test, and can be used for assessing agreement among raters and in particular inter-rater reliability. Kendall's W ranges from 0 (no agreement) to 1 (complete agreement).
Suppose, for instance, that a number of people have been asked to rank a list of political concerns, from the most important to the least important. Kendall's W can be calculated from these data. If the test statistic W is 1, then all the survey respondents have been unanimous, and each respondent has assigned the same order to the list of concerns. If W is 0, then there is no overall trend of agreement among the respondents, and their responses may be regarded as essentially random. Intermediate values of W indicate a greater or lesser degree of unanimity among the various responses.
While tests using the standard Pearson correlation coefficient assume normally distributed values and compare two sequences of outcomes simultaneously, Kendall's W makes no assumptions regarding the nature of the probability distribution and can handle any number of distinct outcomes.
Steps of Kendall's W
Suppose that object i is given the rank ri,j by judge number j, where there are in total n objects and m judges. Then the total rank given to object i is
and the mean value of these total ranks is
The sum of squared deviations, S, is defined as
and then Kendall's W is defined as
If the test statistic W is 1, then all the judges or survey respondents have been unanimous, and each judge or respondent has assigned the same order to the list of objects or concerns. If W is 0, then there is no overall trend of agreement among the respondents, and their responses may be regarded as essentially random. Intermediate values of W indicate a greater or lesser degree of unanimity among the various judges or respondents.
Kendall and Gibbons (1990) also
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https://en.wikipedia.org/wiki/UWB%20Forum
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The UWB Forum was an industry organization promoting interoperable ultra-wideband (UWB) wireless computer networking products from multiple vendors. It was founded in 2004 and disbanded around 2006.
History
The UWB Forum was founded in 2004, promoting acronyms such as DS-UWB and CSM.
Within the Institute of Electrical and Electronics Engineers, the IEEE_802.15.3a effort attempted to provide a higher speed ultra-wideband enhancement amendment to IEEE 802.15.3 for applications which involved imaging and multimedia.
That standardisation attempt failed due to contrasting approaches between the WiMedia Alliance and UWB Forum. On January 19, 2006 IEEE 802.15.3a task group (TG3a) members voted to withdraw the December 2002 project authorization request (PAR) that initiated the development of high data rate wireless standards. The IEEE 802.15.3a did consolidate 23 physical layer specifications into two proposals: multi-band orthogonal frequency-division multiplexing (MB-OFDM), supported by the WiMedia Alliance, and direct sequence - UWB (DS-UWB), supported by the UWB Forum.
Major members Motorola and Freescale Semiconductor left the group in April 2006 and the UWB Forum disbanded.
Its website remained into mid-2007.
UWB Alliance
On December 19, 2018, the UWB Alliance was officially launched to promote interoperable ultra-wideband (UWB) wireless computer networking products from multiple vendors. The founding members include: Hyundai, Kia, Zebra, Decawave, Alteros, Novelda, and Ubisense.
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https://en.wikipedia.org/wiki/David%20Syme
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David Syme (2 October 1827 – 14 February 1908) was a Scottish-Australian newspaper proprietor of The Age and regarded as "the father of protection in Australia" who had immense influence in the Government of Victoria. His first biographer, Ambrose Pratt, declared Syme "could hate as few men can [and] loved power as few men ever loved it".
Early life and family
Syme was born at North Berwick in Scotland, the youngest of the seven children and fourth son of George Alexander Syme (18?–1845), a parish schoolmaster. Syme's wife, David's mother, was Jean née Mitchell. George Syme was a radical in church and state, his income was comfortable yet moderate, but it was stretched to provide for his large family and send three of his sons to universities (which he successfully did, while providing David with a relentlessly demanding education himself.) David Syme's childhood was one of study with little companionship with other boys of his own age. George Syme was not physically unkind to his sons, but Syme would write later: "It was difficult to understand my father's attitude to we boys. He had naturally a kind disposition; he was a devoted husband and no-one ever asked him for help that he did not freely give … but his affection for us never found expression in words".
Syme married Annabella Garnett-Johnson, of the Lancashire Garnett family of Waddow Hall, Clitheroe, England. Annabella was connected through her Garnett relations to William Garnett.
David Syme was 17 years old when his father died and he continued his classical studies with some doubt to his future. He had thoughts of qualifying for the ministry but revolted from the Calvinistic teaching of the day; his brothers George and Ebenezer had renounced the Church of Scotland.
Syme studied under James Morison at Kilmarnock for two years, attended some classes at Heidelberg and returned to Scotland obtaining a position about 1850 as a proofreader's assistant on a Glasgow newspaper. With low pay and little prospect
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https://en.wikipedia.org/wiki/Spring%20Security
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Spring Security is a Java/Java EE framework that provides authentication, authorization and other security features for enterprise applications. The project was started in late 2003 as 'Acegi Security' (pronounced Ah-see-gee , whose letters are the first, third, fifth, seventh, and ninth characters from the English alphabet, in order to prevent name conflicts) by Ben Alex, with it being publicly released under the Apache License in March 2004. Subsequently, Acegi was incorporated into the Spring portfolio as Spring Security, an official Spring sub-project. The first public release under the new name was Spring Security 2.0.0 in April 2008, with commercial support and training available from SpringSource.
Authentication flow
Diagram 1 shows the basic flow of an authentication request using the Spring Security system. It shows the different filters and how they interact from the initial browser request, to either a successful authentication or an HTTP 403 error.
Key authentication features
LDAP (using both bind-based and password comparison strategies) for centralization of authentication information.
Single sign-on capabilities using the popular Central Authentication Service.
Java Authentication and Authorization Service (JAAS) LoginModule, a standards-based method for authentication used within Java. Note this feature is only a delegation to a JAAS Loginmodule.
Basic access authentication as defined through RFC 1945.
Digest access authentication as defined through RFC 2617 and RFC 2069.
X.509 client certificate presentation over the Secure Sockets Layer standard.
CA, Inc SiteMinder for authentication (a popular commercial access management product).
Su (Unix)-like support for switching principal identity over a HTTP or HTTPS connection.
Run-as replacement, which enables an operation to assume a different security identity.
Anonymous authentication, which means that even unauthenticated principals are allocated a security identity.
Container adapter (custom realm)
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https://en.wikipedia.org/wiki/Fortify%20Software
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Fortify Software, later known as Fortify Inc., is a California-based software security vendor, founded in 2003 and acquired by Hewlett-Packard in 2010, Micro Focus in 2017, and OpenText in 2022.
Fortify offerings included Static application security testing (SAST) and Dynamic application security testing products, as well as products and services that support Software Security Assurance. In 2011, Fortify introduced Fortify OnDemand, a static and dynamic application testing service.
History
Fortify Software was founded by Kleiner Perkins in 2003. Fortify Inc. was acquired by HP in 2010.
On September 7, 2016, HPE CEO Meg Whitman announced that the software assets of Hewlett Packard Enterprise, including Fortify, would be merged with Micro Focus to create an independent company of which HP Enterprise shareholders would retain majority ownership.
Micro Focus CEO Kevin Loosemore called the transaction "entirely consistent with our established acquisition strategy and our focus on efficient management of mature infrastructure products" and indicated that Micro Focus intended to "bring the core earnings margin for the mature assets in the deal - about 80 percent of the total - from 21 percent today to Micro Focus's existing 46 percent level within three years." The merge concluded on September 1, 2017.
Technical advisory board
Fortify's technical advisory board was composed of Avi Rubin, Bill Joy, David Wagner, Fred Schneider, Gary McGraw, Greg Morrisett, Li Gong, Marcus Ranum, Matt Bishop, William Pugh, and John Viega.
Security research
Fortify created a security research group that maintained the Java Open Review project and the Vulncat taxonomy of security vulnerabilities in addition to the security rules for Fortify's analysis software. Members of the group wrote the book Secure Coding with Static Analysis, and published research, including JavaScript Hijacking, Attacking the build: Cross build Injection, Watch what you write: Preventing Cross-site scripting by
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https://en.wikipedia.org/wiki/Limosilactobacillus%20reuteri
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Limosilactobacillus reuteri is a lactic acid bacterium found in a variety of natural environments, including the gastrointestinal tract of humans and other animals. It does not appear to be pathogenic and may have health effects.
Discovery
At the turn of the 20th century, L. reuteri was recorded in scientific classifications of lactic acid bacteria, though at this time it was mistakenly grouped as a member of Lactobacillus fermentum. In the 1960s, further work by microbiologist Gerhard Reuter, for whom the species eventually was named, reclassified the species as L. fermentum biotype II.
Significant differences were found between biotype II and other biotypes of L. fermentum, to the point that in 1980 it was identified as a distinct species and the formal species identity, L. reuteri, was proposed. In April 2020, L. reuteri was reassigned to the genus Limosilactobacillus.
Prevalence
Limosilactobacillus reuteri is found in a variety of natural environments. It has been isolated from many foods, especially meats and dairy products. It appears to be essentially ubiquitous in the animal kingdom, having been found in the gastrointestinal tracts and feces of healthy humans, sheep, chickens, pigs, and rodents. It is the only species to constitute a "major component" of the Lactobacillus species present in the gut of each of the tested host animals, and each host seems to harbor its own specific strain of L. reuteri. It is possible that L. reuteri contributes to the health of its host organism in some manner.
Limosilactobacillus reuteri is present as a dominant member of fermenting organisms in type II sourdoughs; several metabolic traits of L. reuteri, including exopolysaccharide formation and conversion of glutamine to glutamate, improve bread quality.
Effects
Antimicrobial
Limosilactobacillus reuteri is known to produce reuterin, reutericin 6 and reutericyclin.
Reuterin
In the late 1980s, Walter Dobrogosz, Ivan Casas and colleagues discovered that L. reuteri p
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https://en.wikipedia.org/wiki/Data%20General%20Eclipse%20MV/8000
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The Eclipse MV/8000 was the first in a family of 32-bit minicomputers produced by Data General during the 1980s. Codenamed Eagle during development, its architecture was a new 32-bit design backward compatible with the previous 16-bit Eclipse series. The development of the computer and the people who worked on it were the subject of Tracy Kidder's book The Soul of a New Machine. The MV/8000 was succeeded by the MV/6000, MV/8000-II, MV/2000, MV/2500, MV/4000, MV/10000, MV15000, MV/20000, MV/30000 and MV/40000. Later models such as the MV/40000 were SMP systems with hot-swappable components.
The Eclipse MV was a 32-bit CISC architecture with a 4 GB address space. The 4 GB address space was divided into eight rings of 512 MB each with a privilege mechanism mapped onto the rings. The outermost ring, ring-7, was the least privileged. The inner-most ring, ring-0, was the most privileged.
The AOS/VS operating system supported the notion of lightweight "tasks" as well as processes. A single process could start various tasks that would all share a global address space (similar to modern "threads"). Tasks were very easy to use from Data General's FORTRAN compiler, and allowed faster context switching than using full processes. One could also start subtasks, using so-called "Son" batch process. This was done using the CLI (Command Line Interpreter). It resulted (de facto) in an online batch process. This process would, however be killed as soon as the user would log off. The MV/8000 had only two "true" batch processes, as not to frustrate the online processes. The "plus" of the online batches was that they ran with the same priority as the normal online processes.
See also
DG/UX
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https://en.wikipedia.org/wiki/Leverage-point%20modeling
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Leverage-point modeling (LPM) is a demonstrated approach for improved planning and spending for operations and support (O&S) activities. LPM is a continuous-event simulation technique that uses the system dynamics approach of model building. Dr. Nathaniel Mass championed the potential of LPM, and adapted it for the Department of Defense (DoD) as a tool for jumping to a higher performance curve as a means of offsetting higher costs and declining budgets. The purpose of LPM is to test policies and investments that improve mission capability for a given level of investment or funding. It is particularly used to evaluate investments in component reliability and parts availability.
DoD context
DoD is moving towards a performance-based strategy and contracting focus as the preferred weapon systems sustainment plan, streamlining contracting and financing mechanisms in order to buy availability and readiness measured by performance criteria. Performance Based Logistics (PBL) strategy is applied to achieve near-term improvements in end-to-end sustainment, material readiness, and Total life-cycle systems management (TLCSM) through public-private partnerships that combine best practice capabilities of industry and organic support. Leverage point models illustrate where small differences in operational thinking can make a large impact on cost, readiness or productivity. In DoD context, these models are built with a perspective (e.g. O&S) that makes clear purpose, and emphasize variables such as the accumulations of end items and components in states of repair and disrepair. LPM identifies high-level leverage points such as reliability investment, improved parts availability, and investment in Diagnosis/Test. LPM results may be used to support Program Objective Memorandum (POM) or Reduced Total Ownership Cost (R-TOC) efforts.
Modeling approach
Leverage point models are typically expressed through differential equations that reflect analysis based on system dynamics, focusin
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https://en.wikipedia.org/wiki/Laplace%20no%20Ma
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is a Japanese video game released in 1987 for the NEC PC-8801 and NEC PC-9801. The game was also ported to Sharp X68000, MSX, the SNES and TurboGrafx-CD. It is part of the Ghost Hunter dungeon crawler series, which also includes Kurokishi no Kamen for the 3DO and Paracelsus no Maken for the NEC PC.
Summary
This video game is a mixture of the role-playing video game and survival horror genres and set in the vicinity of Boston, Massachusetts in a town called "Newcam", it is modeled after the fictional city Arkham created by H. P. Lovecraft.
The horror part of the game lies in the exploration of the fictional Weathertop Mansion, whose owner dabbled in black magic. The game's CRPG features include its character classes—Dilettante, Medium, Detective, Scientist, and Journalist—and that the player can leave the mansion to walk around the town to go to shops to buy items needed to defeat the monsters and complete the game.
Reception
On release, Famicom Tsūshin scored the Super Famicom version of the game a 26 out of 40.
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https://en.wikipedia.org/wiki/Esophageal%20gland
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The esophageal glands are glands that are part of the digestive system of various animals, including humans.
In humans
Esophageal glands in humans are a part of a human digestive system. They are a small compound racemose exocrine glands of the mucous type.
There are two types:
Esophageal glands proper- mucous glands located in the submucosa. They are compound tubulo-alveolar glands. Some serous cells are present. These glands are more numerous in the upper third of the esophagus. They secrete acid mucin for lubrication.
Esophageal cardiac glands- mucous glands located near the cardiac orifice (esophago-gastric junction) in the lamina propria mucosae. They secrete neutral mucin that protects the esophagus from acidic gastric juices. They are simple tubular or branched tubular glands.
There are also mucous glands present at the pharyngo-esophageal junction in the lamina propria mucosae. These are simple tubular or branched tubular glands.
Each opens upon the surface by a long excretory duct.
In monoplacophorans
Oesophageal gland is enlarged in large monoplacophoran species.
In gastropods
Oesophageal gland or oesophageal pouch is a part of the digestive system of some gastropods. Oesophageal gland or pouch is a common feature in so-called basal gastropod clades, including Patelloidea, Vetigastropoda, Cocculiniformia, Neritimorpha and Neomphalina.
The size of oesophageal gland of scaly-foot gastropod Chrysomallon squamiferum (family Peltospiridae within Neomphalina) is about two orders of magnitude over the usual size. The scaly-foot gastropod houses endosymbiotic Bacteria in the oesophageal gland. Chrysomallon squamiferum was thought to be the only species of Peltospiridae, that has enlarged oesophageal gland, but later it was shown that both species Gigantopelta has the oesophageal gland also enlarged. In other peltospirids, the posterior portion of the oesophagus forms a pair of blind mid-oesophageal pouches or gutters extending only to the anterior end o
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https://en.wikipedia.org/wiki/Claviceps%20purpurea
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Claviceps purpurea is an ergot fungus that grows on the ears of rye and related cereal and forage plants. Consumption of grains or seeds contaminated with the survival structure of this fungus, the ergot sclerotium, can cause ergotism in humans and other mammals. C. purpurea most commonly affects outcrossing species such as rye (its most common host), as well as triticale, wheat and barley. It affects oats only rarely.
Life cycle
An ergot kernel called Sclerotium clavus develops when a floret of flowering grass or cereal is infected by an ascospore of C. purpurea. The infection process mimics a pollen grain growing into an ovary during fertilization. Because infection requires access of the fungal spore to the stigma, plants infected by C. purpurea are mainly outcrossing species with open flowers, such as rye (Secale cereale) and Alopecurus.
The proliferating fungal mycelium then destroys the plant ovary and connects with the vascular bundle originally intended for feeding the developing seed. The first stage of ergot infection manifests itself as a white soft tissue (known as Sphacelia segetum) producing sugary honeydew, which often drops out of the infected grass florets. This honeydew contains millions of asexual spores (conidia) which are dispersed to other florets by insects or rain. Later, the Sphacelia segetum convert into a hard dry Sclerotium clavus inside the husk of the floret. At this stage, alkaloids and lipids (e.g. ricinoleic acid) accumulate in the Sclerotium.
When a mature Sclerotium drops to the ground, the fungus remains dormant until proper conditions trigger its fruiting phase (onset of spring, rain period, need of fresh temperatures during winter, etc.). It germinates, forming one or several fruiting bodies with head and stipe, variously colored (resembling a tiny mushroom). In the head, threadlike sexual spores (ascospores) are formed in perithecia, which are ejected simultaneously, when suitable grass hosts are flowering. Ergot infection
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https://en.wikipedia.org/wiki/Cutan%20%28polymer%29
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Cutan is one of two waxy biopolymers which occur in the cuticle of some plants. The other and better-known polymer is cutin. Cutan is believed to be a hydrocarbon polymer, whereas cutin is a polyester, but the structure and synthesis of cutan are not yet fully understood. Cutan is not present in as many plants as once thought; for instance it is absent in Ginkgo.
Cutan was first detected as a non-saponifiable component, resistant to de-esterification by alkaline hydrolysis, that increases in amount in cuticles of some species such as Clivia miniata as they reach maturity, apparently replacing the cutin secreted in the early stages of cuticle development. Evidence that cutan is a hydrocarbon polymer comes from the fact that its flash pyrolysis products are a characteristic homologous series of paired alkanes and alkenes, and through 13C-NMR analysis of present-day and fossil plants.
Cutan's preservation potential is much greater than that of cutin. Despite this, the low proportion of cutan found in fossilized cuticle shows that it is probably not the cause for the widespread preservation of cuticle in the fossil record.
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https://en.wikipedia.org/wiki/FMSX
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fMSX is a portable MSX emulator written by Marat Fayzullin. It is one of the earliest MSX emulators, and is also the most ported. fMSX is written in C with emphasis on portability. fMSX was a very influential and a number of emulators started as forks of fMSX, including blueMSX and paraMSX. The Z80 emulation code by Marat Fayzullin has been used on many other emulators.
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https://en.wikipedia.org/wiki/Anton%20Kapustin
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Anton Nikolayevich Kapustin (born November 10, 1971, Moscow) is a Russian-American theoretical physicist and the Earle C. Anthony Professor of Theoretical Physics at the California Institute of Technology. His interests lie in quantum field theory and string theory, and their applications to particle physics and condensed matter theory. He is the son of the pianist-composer Nikolai Kapustin.
Education
Kapustin obtained a B.S. in physics from Moscow State University in 1993. He received a Ph.D. in physics from the California Institute of Technology in 1997 with John Preskill as his advisor.
Research
He has made several contributions to dualities and other aspects of quantum field theories, in particular topological field theories and supersymmetric gauge theories. With Edward Witten he discovered deep connections between the S-duality of supersymmetric gauge theories and the geometric Langlands correspondence. In recent years, he has focused on mathematical structures in and classification schemes of topological field theories and symmetry-protected topological phases.
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https://en.wikipedia.org/wiki/Henle%27s%20layer
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Henle's layer is the third and the outermost layer of the inner root sheath of the hair follicle, consisting of a single layer of cubical cells with clear flattened nuclei. It is named after German physician, pathologist and anatomist Friedrich Gustav Jakob Henle.
See also
List of distinct cell types in the adult human body
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https://en.wikipedia.org/wiki/Pars%20flaccida%20of%20tympanic%20membrane
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In human anatomy, the pars flaccida of tympanic membrane or Shrapnell's membrane (also known as Rivinus' ligament) is the small, triangular, flaccid portion of the tympanic membrane, or eardrum. It lies above the malleolar folds attached directly to the petrous bone at the notch of Rivinus. On the inner surface of the tympanic membrane, the chorda tympani crosses this area.
The name Shrapnell's membrane refers to Henry Jones Shrapnell, and the name Rivinus' ligament to Augustus Quirinus Rivinus.
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https://en.wikipedia.org/wiki/Joseph%20Gilbert%20Hamilton
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Joseph Gilbert Hamilton (November 11, 1907 – February 18, 1957) was an American professor of Medical Physics, Experimental Medicine, General Medicine, and Experimental Radiology as well as director (1948-1957) of the Crocker Laboratory, part of the Lawrence Berkeley National Laboratory. Hamilton studied the medical effects of exposure to radioactive isotopes, which included the use of unsuspecting human subjects.
He was married to painter Leah Rinne Hamilton.
Early work
Hamilton received his B.S. in Chemistry in 1929 from the University of California. He studied medicine in Berkeley and interned at the University of California Hospital, San Francisco. He was awarded his M.D. degree in 1936. At that time the cyclotron in Berkeley was among the first to produce useful amounts of radioactive isotopes which could be used in studies of their effects on living tissue. In a series of papers published in 1937 Hamilton detailed early medical trials using radioactive sodium, followed by papers detailing the use of the radioactive isotopes of potassium, chlorine, bromine, and iodine. Radioactive iodine was found to be particularly useful in the diagnosis and treatment of thyroid disorders.
Human testing
Concern was expressed over the safety of Manhattan Project laboratory personnel working with newly isolated plutonium in 1944. Hamilton led a team to conduct toxicity experiments on rats. Finding the results unsatisfactory, Hamilton participated in the decision to continue the trials with human subjects. The teams conducted trials in secret from 1945 to 1947.
Three teams headed by Hamilton, Louis Hempelmann and Wright Haskell Langham carried out trials, injecting plutonium into 18 unsuspecting human patients and measuring its concentration in excreta. Joseph Gilbert Hamilton's team injected three of the subjects at University of California Hospital, San Francisco.
Albert Stevens, CAL-1, was diagnosed with terminal stomach cancer, which researchers soon found to have been
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https://en.wikipedia.org/wiki/Antiderivative%20%28complex%20analysis%29
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In complex analysis, a branch of mathematics, the antiderivative, or primitive, of a complex-valued function g is a function whose complex derivative is g. More precisely, given an open set in the complex plane and a function the antiderivative of is a function that satisfies .
As such, this concept is the complex-variable version of the antiderivative of a real-valued function.
Uniqueness
The derivative of a constant function is the zero function. Therefore, any constant function is an antiderivative of the zero function. If is a connected set, then the constant functions are the only antiderivatives of the zero function. Otherwise, a function is an antiderivative of the zero function if and only if it is constant on each connected component of (those constants need not be equal).
This observation implies that if a function has an antiderivative, then that antiderivative is unique up to addition of a function which is constant on each connected component of .
Existence
One can characterize the existence of antiderivatives via path integrals in the complex plane, much like the case of functions of a real variable. Perhaps not surprisingly, g has an antiderivative f if and only if, for every γ path from a to b, the path integral
Equivalently,
for any closed path γ.
However, this formal similarity notwithstanding, possessing a complex-antiderivative is a much more restrictive condition than its real counterpart. While it is possible for a discontinuous real function to have an anti-derivative, anti-derivatives can fail to exist even for holomorphic functions of a complex variable. For example, consider the reciprocal function, g(z) = 1/z which is holomorphic on the punctured plane C\{0}. A direct calculation shows that the integral of g along any circle enclosing the origin is non-zero. So g fails the condition cited above. This is similar to the existence of potential functions for conservative vector fields, in that Green's theorem is only able to gua
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https://en.wikipedia.org/wiki/Shubnikov%E2%80%93de%20Haas%20effect
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An oscillation in the conductivity of a material that occurs at low temperatures in the presence of very intense magnetic fields, the Shubnikov–de Haas effect (SdH) is a macroscopic manifestation of the inherent quantum mechanical nature of matter. It is often used to determine the effective mass of charge carriers (electrons and electron holes), allowing investigators to distinguish among majority and minority carrier populations.
The effect is named after Wander Johannes de Haas and Lev Shubnikov.
Physical process
At sufficiently low temperatures and high magnetic fields, the free electrons in the conduction band of a metal, semimetal, or narrow band gap semiconductor will behave like simple harmonic oscillators. When the magnetic field strength is changed, the oscillation period of the simple harmonic oscillators changes proportionally. The resulting energy spectrum is made up of Landau levels separated by the cyclotron energy. These Landau levels are further split by the Zeeman energy. In each Landau level the cyclotron and Zeeman energies and the number of electron states (eB/h) all increase linearly with increasing magnetic field. Thus, as the magnetic field increases, the spin-split Landau levels move to higher energy. As each energy level passes through the Fermi energy, it depopulates as the electrons become free to flow as current. This causes the material's transport and thermodynamic properties to oscillate periodically, producing a measurable oscillation in the material's conductivity. Since the transition across the Fermi 'edge' spans a small range of energies, the waveform is square rather than sinusoidal, with the shape becoming ever more square as the temperature is lowered.
Theory
Consider a two-dimensional quantum gas of electrons confined in a sample with given width and with edges. In the presence of a magnetic flux density B, the energy eigenvalues of this system are described by Landau levels. As shown in Fig 1, these levels are equid
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https://en.wikipedia.org/wiki/DEC%20Professional
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DEC Professional could refer to:
DEC Professional (computer), a line of PDP-11-based personal computers from Digital Equipment Corporation
The DEC Professional, a now-defunct magazine for administrators and managers of computer systems from Digital Equipment Corporation
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https://en.wikipedia.org/wiki/Newman%27s%20lemma
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In mathematics, in the theory of rewriting systems, Newman's lemma, also commonly called the diamond lemma, states that a terminating (or strongly normalizing) abstract rewriting system (ARS), that is, one in which there are no infinite reduction sequences, is confluent if it is locally confluent. In fact a terminating ARS is confluent precisely when it is locally confluent.
Equivalently, for every binary relation with no decreasing infinite chains and satisfying a weak version of the diamond property, there is a unique minimal element in every connected component of the relation considered as a graph.
Today, this is seen as a purely combinatorial result based on well-foundedness due to a proof of Gérard Huet in 1980. Newman's original proof was considerably more complicated.
Diamond lemma
In general, Newman's lemma can be seen as a combinatorial result about binary relations → on a set A (written backwards, so that a → b means that b is below a) with the following two properties:
→ is a well-founded relation: every non-empty subset X of A has a minimal element (an element a of X such that a → b for no b in X). Equivalently, there is no infinite chain . In the terminology of rewriting systems, → is terminating.
Every covering is bounded below. That is, if an element a in A covers elements b and c in A in the sense that and , then there is an element d in A such that and , where denotes the reflexive transitive closure of →. In the terminology of rewriting systems, → is locally confluent.
The lemma states that if the above two conditions hold, then → is confluent: whenever and , there is an element d such that and . In view of the termination of →, this implies that every connected component of → as a graph contains a unique minimal element a, moreover for every element b of the component.
Notes
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https://en.wikipedia.org/wiki/Apcupsd
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Apcupsd, short for APC UPS daemon, is a utility that runs on Linux, UNIX, macOS and Windows. It allows the computer to interact with APC UPSes. Apcupsd also works with some OEM-branded products (e.g. Hewlett-Packard) manufactured by APC.
Apcupsd is a free software equivalent of the APC's proprietary PowerChute software. As of version 3.14, Apcupsd has support for the PowerChute Network Shutdown function as well as many other features.
Apcupsd runs in daemon mode so to keep a live connection with the UPS. Depending on the settings and type of connection, Apcupsd either polls the UPS to learn about its current state, or receives messages from the UPS itself (e.g. via SNMP traps). Possible types of connections to the UPS are USB, RS-232 or Ethernet.
Apcupsd can communicate with other instances of Apcupsd on other computers and maintain a client-server relationship with them. This way it is possible to power multiple computers with one UPS, even though only one of them is connected to the data port of the UPS.
See also
APC Smart-UPS
Network UPS Tools, an alternative to Apcupsd, that supports some APC UPS
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https://en.wikipedia.org/wiki/Fibre%20Channel%20Protocol
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Fibre Channel Protocol (FCP) is the SCSI interface protocol utilising an underlying Fibre Channel connection. The Fibre Channel standards define a high-speed data transfer mechanism that can be used to connect workstations, mainframes, supercomputers, storage devices and displays. FCP addresses the need for very fast transfers of large volumes of information and could relieve system manufacturers from the burden of supporting a variety of channels and networks, as it provides one standard for networking, storage and data transfer.
Some Fibre Channel characteristics are:
Performance from 266 megabits/second to 16 gigabits/second
Support both optical and copper media, with distances up to 10 km.
Small connectors (sfp+ are most common)
High-bandwidth utilisation with distance insensitivity
Support for multiple cost/performance levels, from small systems to supercomputers
Ability to carry multiple existing interface command sets, including Internet Protocol (IP), SCSI, IPI, HIPPI-FP, and audio/video.
Fibre Channel consists of the following layers:
FC-0 -- The interface to the physical media
FC-1 -- The encoding and decoding of data and out-of-band physical link control information for transmission over the physical media
FC-2 -- The transfer of frames, sequences and exchanges comprising protocol information units.
FC-3 -- Common services required for advanced features such as striping, hunt group and multicast.
FC-4 -- Application interfaces that can execute over Fibre Channel such as the Fibre Channel Protocol for SCSI (FCS).
Unlike a layered network architecture, a Fibre Channel network is largely specified by functional elements and the interfaces between them. These consist, in part, of the following:
N_PORTs—The end points for traffic.
FC Devices—The devices to which the N_PORTs provide access.
Fabric Ports—The interfaces within a network that provide attachment for an N_PORT.
The network infrastructure for carrying frame traffic between N_PORTs.
Within a
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https://en.wikipedia.org/wiki/MAFOR
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MAFOR, an abbreviation of MArine FORecast, is a North American code used in the transmission of marine weather forecasts to compress a volume of meteorological and marine information into shorter code for convenience during radio broadcasting. The MAFOR forecast usually supplies the period of validity for the forecast, future wind speed and direction, weather, visibility and 'state of sea.'
Format
A MAFOR code begins with a date and time group, followed by the name of the area to which the forecast applies, followed by one or more groups of five figures, which may be followed by another optional group.
Date Group
YYG1G1/ where
YY is the day of the month in accordance with Coordinated Universal Time (UTC)
G1G1 is the time of the beginning of the valid period of the forecasts in Coordinated Universal Time (UTC).
"/" is the last digit of this group is not used.
Weather Group
1GDFmW1
1: is an identifying number required by international practice. Each code group following the name of the lake will begin with 1.
G: is the code figure for the period of time covered by the forecast given in the group.
Time Period of Forecast Coverage
0 - Existing weather conditions at the beginning of the forecast period
1 - Forecast valid for 3 hours
2 - Forecast valid for 6 hours
3 - Forecast valid for 9 hours
4 - Forecast valid for 12 hours
5 - Forecast valid for 18 hours
6 - Forecast valid for 24 hours
7 - Forecast valid for 48 hours
8 - Forecast valid for 72 hours
9 - Occasionally
D: is the code figure for the forecast direction of the wind.
Direction of Wind
0 - Calm
1 - Northeast
2 - East
3 - Southeast
4 - South
5 - Southwest
6 - West
7 - Northwest
8 - North
9 - Variable
Fm: is the code figure for the forecast speed of the wind
Speed of Wind
0 - Beaufort Number 0-3 (0 - 10 knots)
1 - Beaufort Number 4 (11 - 16 knots)
2 - Beaufort Number 5 (17 - 21 knots)
3 - Beaufort Number 6 (22 - 27 knots)
4 - Beaufort Number 7
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https://en.wikipedia.org/wiki/Physiology%20of%20dinosaurs
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The physiology of dinosaurs has historically been a controversial subject, particularly their thermoregulation. Recently, many new lines of evidence have been brought to bear on dinosaur physiology generally, including not only metabolic systems and thermoregulation, but on respiratory and cardiovascular systems as well.
During the early years of dinosaur paleontology, it was widely considered that they were sluggish, cumbersome, and sprawling cold-blooded lizards. However, with the discovery of much more complete skeletons in western United States, starting in the 1870s, scientists could make more informed interpretations of dinosaur biology and physiology. Edward Drinker Cope, opponent of Othniel Charles Marsh in the Bone Wars, propounded at least some dinosaurs as active and agile, as seen in the painting of two fighting Laelaps produced under his direction by Charles R. Knight.
In parallel, the development of Darwinian evolution, and the discoveries of Archaeopteryx and Compsognathus, led Thomas Henry Huxley to propose that dinosaurs were closely related to birds. Despite these considerations, the image of dinosaurs as large reptiles had already taken root, and most aspects of their paleobiology were interpreted as being typically reptilian for the first half of the twentieth century. Beginning in the 1960s and with the advent of the Dinosaur Renaissance, views of dinosaurs and their physiology have changed dramatically, including the discovery of feathered dinosaurs in Early Cretaceous age deposits in China, indicating that birds evolved from highly agile maniraptoran dinosaurs.
History
Early interpretations
The study of dinosaurs began in the 1820s in England. Pioneers in the field, such as William Buckland, Gideon Mantell, and Richard Owen, interpreted the first, very fragmentary remains as belonging to large quadrupedal beasts. Their early work can be seen today in the Crystal Palace Dinosaurs, constructed in the 1850s, which present known dinosaurs a
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https://en.wikipedia.org/wiki/Testicular%20artery
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The testicular artery (the male gonadal artery, also called the internal spermatic arteries in older texts) is a branch of the abdominal aorta that supplies blood to the testis. It is a paired artery, with one for each of the testes.
It is the male equivalent of the ovarian artery. Because the testis is found in a different location than that of its female equivalent, it has a different course than the ovarian artery.
They are two slender vessels of considerable length, and arise from the front of the aorta a little below the renal arteries.
Each passes obliquely downward and lateralward behind the peritoneum, resting on the psoas major, the right lying in front of the inferior vena cava and behind the middle colic and ileocolic arteries and the terminal part of the ileum, the left behind the left colic and sigmoid arteries and the iliac colon.
Each crosses obliquely over the ureter and the lower part of the external iliac artery to reach the abdominal inguinal ring, through which it passes, and accompanies the other constituents of the spermatic cord along the inguinal canal to the scrotum, where it becomes tortuous, and divides into several branches.
Two or three of these accompany the ductus deferens, and supply the epididymis, anastomosing with the artery of the ductus deferens; others pierce the back part of the tunica albuginea, and supply the substance of the testis.
The internal spermatic artery supplies one or two small branches to the ureter, and in the inguinal canal gives one or two twigs to the cremaster.
Additional images
See also
Testicular vein
Ovarian vein
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https://en.wikipedia.org/wiki/Testicular%20vein
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The testicular vein (or spermatic vein), the male gonadal vein, carries deoxygenated blood from its corresponding testis to the inferior vena cava or one of its tributaries. It is the male equivalent of the ovarian vein, and is the venous counterpart of the testicular artery.
Structure
It is a paired vein, with one supplying each testis:
the right testicular vein generally joins the inferior vena cava;
the left testicular vein, unlike the right one, joins the left renal vein instead of the inferior vena cava.
The veins emerge from the back of the testis, and receive tributaries from the epididymis. They unite and form a convoluted plexus, called the pampiniform plexus, which constitutes the greater mass of the spermatic cord; the vessels composing this plexus are very numerous, and ascend along the cord, in front of the ductus deferens.
Below the subcutaneous inguinal ring, they unite to form three or four veins, which pass along the inguinal canal, and, entering the abdomen through the abdominal inguinal ring, coalesce to form two veins, which ascend on the Psoas major, behind the peritoneum, lying one on either side of the internal spermatic artery.
These unite to form a single vein, which opens, on the right side, into the inferior vena cava (at an acute angle), on the left side into the left renal vein (at a right angle).
The left spermatic vein passes behind the iliac colon and is thus exposed to pressure from the contents of that part of the bowel.
Variation
The testicular veins usually have valves. However, in post-mortem examinations it was found that up to 40% of left testicular veins lack valves, and up to 23% of right testicular veins lack valves.
Clinical significance
Varicocele
Valveless testicular veins are a major contributing factor to varicocele. Since the left testicular vein goes all the way up to the left renal vein before it empties, this results in a higher tendency for the left testicle to develop varicocele because of the gravity
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https://en.wikipedia.org/wiki/Airy%20points
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Airy points (after George Biddell Airy) are used for precision measurement (metrology) to support a length standard in such a way as to minimise bending or drop of a horizontally supported beam.
Choice of support points
A kinematic support for a one-dimensional beam requires exactly two support points. Three or more support points will not share the load evenly (unless they are hinged in a non-rigid whiffle tree or similar). The position of those points can be chosen to minimize various forms of gravity deflection.
A beam supported at the ends will sag in the middle, resulting in the ends moving closer together and tilting upward. A beam supported only in the middle will sag at the ends, making a similar shape but upside down.
Airy points
Supporting a uniform beam at the Airy points produces zero angular deflection of the ends. The Airy points are symmetrically arranged around the centre of the length standard and are separated by a distance equal to
of the length of the rod.
"End standards", that is standards whose length is defined as the distance between their flat ends such as long gauge blocks or the , must be supported at the Airy points so that their length is well-defined; if the ends are not parallel, the measurement uncertainty is increased because the length depends on which part of the end is measured. For this reason, the Airy points are commonly identified by inscribed marks or lines. For example, a 1000 mm length gauge would have an Airy point separation of 577.4 mm. A line or pair of lines would be marked onto the gauge 211.3 mm in from each end. Supporting the artifact at these points ensures that the calibrated length is preserved.
Airy's 1845 paper derives the equation for equally spaced support points. In this case, the distance between each support is the fraction
the length of the rod. He also derives the formula for a rod which extends beyond the reference marks.
Bessel points
"Line standards" are measured between line
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https://en.wikipedia.org/wiki/Nathan%20Fine
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Nathan Jacob Fine (22 October 1916 in Philadelphia – 18 November 1994 in Deerfield Beach, Florida) was an American mathematician who worked on basic hypergeometric series. He is best known for his lecture notes on the subject which for four decades served as an inspiration to experts in the field until they were finally published as a book. He solved the Jeep problem in 1946.
Nathan Fine retired in 1978 as a professor at Pennsylvania State University. Prior to that he had been on the faculties of the University of Pennsylvania and Cornell University. For a brief period (1946–1947) he also worked at the Operations Evaluation Group, affiliated with the Massachusetts Institute of Technology. Beside the book he published about 40 papers in several fields of mathematics. He is known for the Rogers-Fine identity.
Nathan Fine received his Ph.D. in 1946 from University of Pennsylvania, where he was a student of Antoni Zygmund. Fine was at the Institute for Advanced Study for the three academic years 1953–1954, 1958–1959, and 1959–1960. Fine's doctoral students include J. J. Price.
He wrote the book Basic Hypergeometric Series and Applications .
Selected publications
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https://en.wikipedia.org/wiki/Herbrand%20quotient
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In mathematics, the Herbrand quotient is a quotient of orders of cohomology groups of a cyclic group. It was invented by Jacques Herbrand. It has an important application in class field theory.
Definition
If G is a finite cyclic group acting on a G-module A, then the cohomology groups Hn(G,A) have period 2 for n≥1; in other words
Hn(G,A) = Hn+2(G,A),
an isomorphism induced by cup product with a generator of H2(G,Z). (If instead we use the Tate cohomology groups then the periodicity extends down to n=0.)
A Herbrand module is an A for which the cohomology groups are finite. In this case, the Herbrand quotient h(G,A) is defined to be the quotient
h(G,A) = |H2(G,A)|/|H1(G,A)|
of the order of the even and odd cohomology groups.
Alternative definition
The quotient may be defined for a pair of endomorphisms of an Abelian group, f and g, which satisfy the condition fg = gf = 0. Their Herbrand quotient q(f,g) is defined as
if the two indices are finite. If G is a cyclic group with generator γ acting on an Abelian group A, then we recover the previous definition by taking f = 1 - γ and g = 1 + γ + γ2 + ... .
Properties
The Herbrand quotient is multiplicative on short exact sequences. In other words, if
0 → A → B → C → 0
is exact, and any two of the quotients are defined, then so is the third and
h(G,B) = h(G,A)h(G,C)
If A is finite then h(G,A) = 1.
For A is a submodule of the G-module B of finite index, if either quotient is defined then so is the other and they are equal: more generally, if there is a G-morphism A → B with finite kernel and cokernel then the same holds.
If Z is the integers with G acting trivially, then h(G,Z) = |G|
If A is a finitely generated G-module, then the Herbrand quotient h(A) depends only on the complex G-module C⊗A (and so can be read off from the character of this complex representation of G).
These properties mean that the Herbrand quotient is usually relatively easy to calculate, and is often much easier to calculate than the orders
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https://en.wikipedia.org/wiki/Lofoten%20Stockfish%20Museum
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Lofoten Stockfish Museum (Lofoten Tørrfiskmuseum) is located in the village of Å in the municipality of Moskenes, in the Lofoten islands in the county of Nordland, Norway.
The Lofoten Stockfish Museum is devoted to the production of Norwegian stockfish, one of Norway's oldest export commodity. The Museum is located in an old fish landing station. The museum displays the process from when the fish is brought ashore until it is finally packaged and ready for export.
There are two museums located at Å in Lofoten, the other being the Norwegian Fishing Village Museum (Norsk Fiskeværsmuseum).
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https://en.wikipedia.org/wiki/Locus%20control%20region
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A locus control region (LCR) is a long-range cis-regulatory element that enhances expression of linked genes at distal chromatin sites. It functions in a copy number-dependent manner and is tissue-specific, as seen in the selective expression of β-globin genes in erythroid cells. Expression levels of genes can be modified by the LCR and gene-proximal elements, such as promoters, enhancers, and silencers. The LCR functions by recruiting chromatin-modifying, coactivator, and transcription complexes. Its sequence is conserved in many vertebrates, and conservation of specific sites may suggest importance in function. It has been compared to a super-enhancer as both perform long-range cis regulation via recruitment of the transcription complex.
History
The β-globin LCR was identified over 20 years ago in studies of transgenic mice. These studies determined that the LCR was required for normal regulation of beta-globin gene expression. Evidence of the presence of this additional regulatory element came from a group of patients that lacked a 20 kb region upstream of the β-globin cluster that was vital for expression of any of the β-globin genes. Even though all of the genes themselves and the other regulatory elements were intact, without this domain, none of the genes in the β-globin cluster were expressed.
Examples
Although the name implies that the LCR is limited to a single region, this implication only applies to the β-globin LCR (HBB-LCR). Other studies have found that a single LCR can be distributed in multiple areas around and inside the genes it controls. The β-globin LCR in mice and humans is found 6–22 kb upstream of the first globin gene (epsilon). It controls the following genes:
HBE1, hemoglobin subunit epsilon (embryonic)
HBG2, hemoglobin subunit gamma-2 (fetal)
HBG1, hemoglobin subunit gamma-1 (fetal)
HBD, hemoglobin subunit delta (adult)
HBB, hemoglobin subunit beta (adult)
There is an opsin LCR (OPSIN-LCR) controlling the expression of OPN1LW
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https://en.wikipedia.org/wiki/Dual-polarization%20interferometry
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Dual-polarization interferometry (DPI) is an analytical technique that probes molecular layers adsorbed to the surface of a waveguide using the evanescent wave of a laser beam. It is used to measure the conformational change in proteins, or other biomolecules, as they function (referred to as the conformation activity relationship).
Instrumentation
DPI focuses laser light into two waveguides. One of these functions as the "sensing" waveguide having an exposed surface while the second one functions to maintain a reference beam. A two-dimensional interference pattern is formed in the far field by combining the light passing through the two waveguides. The DPI technique rotates the polarization of the laser, to alternately excite two polarization modes of the waveguides. Measurement of the interferogram for both polarizations allows both the refractive index and the thickness of the adsorbed layer to be calculated. The polarization can be switched rapidly, allowing real-time measurements of chemical reactions taking place on a chip surface in a flow-through system. These measurements can be used to infer conformational information about the molecular interactions taking place, as the molecule size (from the layer thickness) and the fold density (from the RI) change. DPI is typically used to characterize biochemical interactions by quantifying any conformational change at the same time as measuring reaction rates, affinities and thermodynamics.
The technique is quantitative and real-time (10 Hz) with a dimensional resolution of 0.01 nm.
Extensions of dual-polarization interferometry also exist, namely multiple pathlength dual-polarization interferometry (MPL-DPI) and absorption enhanced DPI. In MPL-DPI quantification of both layer thickness and refractive index (density) and therefore mass per unit area can be made for in situ and ex-situ coated films, where normal DPI can only calculate film properties if the interferogram is constantly monitored. Absorption enhance
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https://en.wikipedia.org/wiki/It%27s%20Raining%2C%20It%27s%20Pouring
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"It's Raining, It's Pouring" is an English language nursery rhyme and children's song. It has a Roud Folk Song Index number of 16814.
Origins
The first two lines of this rhyme can be found in The Little Mother Goose, published in the US in 1912. The melody is associated with "A Tisket, A Tasket" and "What Are Little Boys Made Of?"
The earliest known audio recording of the song was made in 1939 in New York by anthropologist and folklorist Herbert Halpert and is held in the Library of Congress. Charles Ives added musical notes 1939, and a version of it was copyrighted in 1944 by Freda Selicoff.
The poem goes as follows:
It's raining, it's pouring,
The old man is snoring,
He went to bed and bumped his head,
And couldn't get up in the morning.
Interpretation
It has been suggested that the verse is a "classic description" of a head injury ("bumped his head"), followed by a lucid interval and an inability to resume normal activity ("couldn't get up in the morning"). Andrew Kaye in Essential Neurosurgery suggested that, in regard to the first verse at least, the rhyme is an interpretation of an accidental death ("couldn't get up in the morning"; indicating that no attempt or ability to get up was made).
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https://en.wikipedia.org/wiki/Haber%E2%80%93Weiss%20reaction
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The Haber–Weiss reaction generates •OH (hydroxyl radicals) from H2O2 (hydrogen peroxide) and superoxide (•O2−) catalyzed by iron ions. It was first proposed by Fritz Haber and his student Joseph Joshua Weiss in 1932.
This reaction has long been studied and revived in different contexts, including organic chemistry, free radicals, radiochemistry, and water radiolysis. In the 1970, with the emerging interest for the effect of free radicals onto the ageing mechanisms of living cells due to oxygen (O2), it was proposed that the Haber–Weiss reaction was a source of radicals responsible for cellular oxidative stress. However, this hypothesis was later disproved by several research works. The oxidative stress toxicity is not caused by the Haber–Weiss reaction as a whole, but by the Fenton reaction, which is one specific part of it.
The reaction is kinetically slow, but is catalyzed by dissolved iron ions. The first step of the catalytic cycle involves the reduction of the ferric (Fe3+) ion into the ferrous (Fe2+) ion:
Fe3+ + •O2− → Fe2+ + O2
The second step is the Fenton reaction:
Fe2+ + H2O2 → Fe3+ + OH− + •OH
Net reaction:
•O2− + H2O2 → •OH + OH− + O2
Haber-Weiss chain reaction
The main finding of Haber and Weiss was that hydrogen peroxide (H2O2) is decomposed by a chain reaction.
The Haber–Weiss reaction chain proceeds by successive steps: (i) initiation, (ii) propagation and (iii) termination.
The chain is initiated by the Fenton reaction:
Fe2+ + H2O2 → Fe3+ + HO– + HO• (step 1: initiation)
Then, the reaction chain propagates by means of two successive steps:
HO• + H2O2 → H2O + O2•– + H+ (step 2: propagation)
O2•– + H+ + H2O2 → O2 + HO• + H2O (step 3: propagation)
Finally, the chain is terminated when the hydroxyl radical is scavenged by a ferrous ion:
Fe2+ + HO• + H+ → Fe3+ + H2O (step 4: termination)
George showed in 1947 that, in water, step 3 cannot compete with the spontaneous disproportionation of superoxide
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https://en.wikipedia.org/wiki/Disease%20theory%20of%20alcoholism
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The modern disease theory of alcoholism states that problem drinking is sometimes caused by a disease of the brain, characterized by altered brain structure and function.
The largest association of physicians – the American Medical Association (AMA) – declared that alcoholism was an illness in 1956. In 1991, the AMA further endorsed the dual classification of alcoholism by the International Classification of Diseases under both psychiatric and medical sections.
Theory
Alcoholism is a chronic problem. However, if managed properly, damage to the brain can be stopped and to some extent reversed. In addition to problem drinking, the disease is characterized by symptoms including an impaired control over alcohol, compulsive thoughts about alcohol, and distorted thinking. Alcoholism can also lead indirectly, through excess consumption, to physical dependence on alcohol, and diseases such as cirrhosis of the liver.
The risk of developing alcoholism depends on many factors, such as environment. Those with a family history of alcoholism are more likely to develop it themselves (Enoch & Goldman, 2001); however, many individuals have developed alcoholism without a family history of the disease. Since the consumption of alcohol is necessary to develop alcoholism, the availability of and attitudes towards alcohol in an individual's environment affect their likelihood of developing the disease. Current evidence indicates that in both men and women, alcoholism is 50–60% genetically determined, leaving 40-50% for environmental influences.
In a review in 2001, McLellan et al. compared the diagnoses, heritability, etiology (genetic and environmental factors), pathophysiology, and response to treatments (adherence and relapse) of drug dependence vs type 2 diabetes mellitus, hypertension, and asthma. They found that genetic heritability, personal choice, and environmental factors are comparably involved in the etiology and course of all of these disorders, providing evidenc
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https://en.wikipedia.org/wiki/Faber%E2%80%93Jackson%20relation
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The Faber–Jackson relation provided the first empirical power-law relation between the luminosity and the central stellar velocity dispersion of elliptical galaxy, and was presented by the astronomers Sandra M. Faber and Robert Earl Jackson in 1976. Their relation can be expressed mathematically as:
with the index approximately equal to 4.
In 1962, Rudolph Minkowski had discovered and wrote that a "correlation between velocity dispersion and [luminosity] exists, but it is poor" and that "it seems important to extend the observations to more objects, especially at low and medium absolute magnitudes". This was important because the value of depends on the range of galaxy luminosities that is fitted, with a value of 2 for low-luminosity elliptical galaxies discovered by a team led by Roger Davies, and a value of 5 reported by Paul L. Schechter for luminous elliptical galaxies.
The Faber–Jackson relation is understood as a projection of the fundamental plane of elliptical galaxies. One of its main uses is as a tool for determining distances to external galaxies.
Theory
The gravitational potential of a mass distribution of radius and mass is given by the expression:
Where α is a constant depending e.g. on the density profile of the system and G is the gravitational constant. For a constant density,
The kinetic energy is:
(Recall is the 1-dimensional velocity dispersion. Therefore, .) From the virial theorem ( ) it follows
If we assume that the mass to light ratio, , is constant, e.g. we can use this and the above expression to obtain a relation between and :
Let us introduce the surface brightness, and assume this is a constant
(which from a fundamental theoretical point of view, is a totally unjustified assumption) to get
Using this and combining it with the relation between and , this results in
and by rewriting the above expression, we finally obtain the relation between luminosity and velocity dispersion:
that is
Given that mass
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https://en.wikipedia.org/wiki/Raman%20Research%20Institute
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The Raman Research Institute (RRI) is an institute for scientific research located in Bengaluru, India. It was founded by Nobel laureate C. V. Raman in 1948. Although it began as an institute privately owned by Sir C. V. Raman, it is now funded by the government of India.
History
Before Raman considered founding a research institute, he had approached the former Maharaja of Mysore seeking land to build office and conference premises for the Indian Academy of Sciences (IAS). The Maharaja acceded to Raman's request and a plot of land in the Malleshwaram suburb of Bengaluru was allotted to the Indian Academy of Sciences in 1934. However, the Academy (then headed by Raman) made no use of the land for seven years. According to the terms of the deal with the Maharaja, the land could be to another use by the government of Mysore if it still remained unused at the end of 1941.
Raman, as President of the IAS, held an extraordinary meeting of the academy in 1941, and proposed that a research institute (to be named after himself) be built on the land. The proposal was approved and a foundational stone was laid on the ground, signifying that the land was now in use. However, it was not until 1948 that the institute was opened. Raman had planned the institute much before he retired as the head of the Physics Department of the Indian Institute of Science. His idea had been to move directly to his newly founded institute when he retired from IISc. This happened in 1948 - Thus, the Raman Research Institute began under the umbrella of the Indian Academy of Sciences, and both under Raman's leadership.
Raman had an apparent hatred for writing project reports or having to give periodic status reports to project funders. For this reason, Raman refused to accept any funds from the Indian government and other sources. "He was of the firm belief that science could not be done that way,” said Prof. N. V Madhusudana, Dean of Research at the RRI and a liquid crystal scientist. As a Nobe
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https://en.wikipedia.org/wiki/Convalescence
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Convalescence is the gradual recovery of health and strength after illness or injury.
Details
It refers to the later stage of an infectious disease or illness when the patient recovers and returns to previous health, but may continue to be a source of infection to others even if feeling better. In this sense, "recovery" can be considered a synonymous term. This also sometimes includes patient care after a major surgery, under which they are required to visit the doctor for regular check-ups.
Convalescent care facilities are sometimes recognized by the acronym TCF (Transitional Convalescent Facilities).
Traditionally, time has been allowed for convalescence to happen. Nowadays, in some instances, where there is a shortage of hospital beds or of trained staff, medical settings can feel rushed and may have drifted away from a focus on convalescence.
See also
Rehabilitation, therapy to control a medical condition such as an addiction
Recuperation (recovery), a period of physical or mental recovery
Recuperation (sociology), a sociological concept
Relapse, reappearance of symptoms
Remission, absence of symptoms in chronic diseases
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https://en.wikipedia.org/wiki/Map%20%28higher-order%20function%29
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In many programming languages, map is the name of a higher-order function that applies a given function to each element of a collection, e.g. a list or set, returning the results in a collection of the same type. It is often called apply-to-all when considered in functional form.
The concept of a map is not limited to lists: it works for sequential containers, tree-like containers, or even abstract containers such as futures and promises.
Examples: mapping a list
Suppose we have a list of integers [1, 2, 3, 4, 5] and would like to calculate the square of each integer. To do this, we first define a function to square a single number (shown here in Haskell):
square x = x * x
Afterwards we may call
>>> map square [1, 2, 3, 4, 5]
which yields [1, 4, 9, 16, 25], demonstrating that map has gone through the entire list and applied the function square to each element.
Visual example
Below, you can see a view of each step of the mapping process for a list of integers X = [0, 5, 8, 3, 2, 1] that we want to map into a new list X' according to the function :
The map is provided as part of the Haskell's base prelude (i.e. "standard library") and is implemented as:
map :: (a -> b) -> [a] -> [b]
map _ [] = []
map f (x : xs) = f x : map f xs
Generalization
In Haskell, the polymorphic function map :: (a -> b) -> [a] -> [b] is generalized to a polytypic function fmap :: Functor f => (a -> b) -> f a -> f b, which applies to any type belonging the Functor type class.
The type constructor of lists [] can be defined as an instance of the Functor type class using the map function from the previous example:
instance Functor [] where
fmap = map
Other examples of Functor instances include trees:
-- a simple binary tree
data Tree a = Leaf a | Fork (Tree a) (Tree a)
instance Functor Tree where
fmap f (Leaf x) = Leaf (f x)
fmap f (Fork l r) = Fork (fmap f l) (fmap f r)
Mapping over a tree yields:
>>> fmap square (Fork (Fork (Leaf 1) (Leaf 2)) (Fork (Leaf 3)
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https://en.wikipedia.org/wiki/Key%20rollover
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Key rollover is the ability of a computer keyboard to correctly handle several simultaneous keystrokes. A keyboard with n-key rollover (NKRO) can correctly detect input from each key on the keyboard at the same time, regardless of how many other keys are also being pressed. Keyboards that lack full rollover will register an incorrect keystroke when certain combinations of keys are pressed simultaneously. Rollover has applications for stenotype, electronic music keyboards, gaming, and touch-typing generally.
Keyboard usage
During normal typing on a conventional computer keyboard, only one key is usually pressed at any given time, then released before the next key is pressed. However, this is not always the case. When using modifier keys such as Shift or Control, the user intentionally holds the modifier key(s) while pressing and releasing another key.
Rapid typists may also sometimes inadvertently press a key before releasing the previous one.
Certain unusual forms of keyboarding require multiple keys to be pressed or held down simultaneously;
for example:
Braille2000 keying requires as many as six keys to be pressed at once analogous to the six dot keys of a Braille typewriter.
Stenographic typing also requires the ability to press multiple keys at once to form "chords."
Some computer games require multiple keys (other than the usual modifier keys) to be held down while others are pressed and released, in order to perform actions simultaneously;
a common scenario would be the holding down of two Arrow keys or WASD keys in order to move the player in a diagonal direction.
Other scenarios might be pressing a key to interact with an object or item in the game while holding down an Arrow key to signify movement.
n-key rollover
Certain high-end keyboards have -key rollover (NKRO). This means that each key is scanned completely independently by the keyboard hardware, so that each keypress is correctly detected regardless of how many other keys are being pressed
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https://en.wikipedia.org/wiki/STD%208
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STD 8 refers to two Internet Engineering Task Force standards proposed by Jonathan B. Postel and Joyce K. Reynolds from University of Southern California Information Sciences Institute in their Request for Comments published in May 1983.
Among other features Telnet protocol was assigned server port 23.
STD 8 (RFC 854): Telnet Protocol Specification
STD 8 (RFC 855): Telnet Option Specifications
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https://en.wikipedia.org/wiki/Twisted%20nematic%20field%20effect
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The twisted nematic effect (TN-effect) was a main technology breakthrough that made LCDs practical. Unlike earlier displays, TN-cells did not require a current to flow for operation and used low operating voltages suitable for use with batteries. The introduction of TN-effect displays led to their rapid expansion in the display field, quickly pushing out other common technologies like monolithic LEDs and CRTs for most electronics. By the 1990s, TN-effect LCDs were largely universal in portable electronics, although since then, many applications of LCDs adopted alternatives to the TN-effect such as in-plane switching (IPS) or vertical alignment (VA).
Many monochrome alphanumerical displays without picture information still use TN LCDs.
TN displays benefit from fast pixel response times and less smearing than other LCD display technology, but suffer from poor color reproduction and limited viewing angles, especially in the vertical direction. Colors will shift, potentially to the point of completely inverting, when viewed at an angle that is not perpendicular to the display.
Description
The twisted nematic effect is based on the precisely controlled realignment of liquid crystal molecules between different ordered molecular configurations under the action of an applied electric field. This is achieved with little power consumption and at low operating voltages. The underlying phenomenon of alignment of liquid crystal molecules in applied field is called Fréedericksz transition and was discovered by Russian physicist Vsevolod Frederiks in 1927.
The illustrations to the right show both the OFF and the ON-state of a single picture element (pixel) of a twisted nematic light modulator liquid crystal display operating in the "normally white" mode, i.e., a mode in which light is transmitted when no electrical field is applied to the liquid crystal.
In the OFF state, i.e., when no electrical field is applied, a twisted configuration (aka helical structure or helix) of n
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https://en.wikipedia.org/wiki/4-Hydroxycoumarins
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4-Hydroxycoumarins are a class of vitamin K antagonist (VKA) anticoagulant drug molecules derived from coumarin by adding a hydroxy group at the 4 position to obtain 4-hydroxycoumarin, then adding a large aromatic substituent at the 3-position (the ring-carbon between the hydroxyl and the carbonyl). The large 3-position substituent is required for anticoagulant activity.
The primary mechanism of the 4-hydroxycoumarin drugs is the inhibition of vitamin K epoxide reductase. These compounds are not direct antagonists (in the pharmaceutical sense) of vitamin K, but rather act to deplete reduced vitamin K in tissues. For this reason vitamin K antagonizes their effect, and this has led to the loose terminology of vitamin K antagonism.
Origin
Although 4-hydroxycoumarin itself is not an anticoagulant, it is an important fungal metabolite from the precursor coumarin, which is also not an anticoagulant, and its production leads to further fermentative production of the natural anticoagulant dicoumarol. This happens in the presence of naturally occurring formaldehyde, which allows attachment of a second 4-hydroxycoumarin molecule through the linking carbon of the formaldehyde, to the 3-position of the first 4-hydroxycoumarin molecule, giving the semi-dimer the motif of the drug class. Dicoumarol appears in spoiled sweet clover silages and is considered a natural chemical substance of combined plant and fungal origin; mycotoxin also shares these properties. The identification of dicoumarol in 1940 is the precursor of the drug class known as 4-hydroxycoumarins.
Effect
The synthetic drugs in the 4-hydroxycoumarin class are all noted primarily for their use as anticoagulants, though they can have several additional effects. All affect the normal metabolism of vitamin K in the body by inhibiting the enzyme vitamin K epoxide reductase which recycles vitamin K to active form. As such, these compounds form the most important and widely used subset of vitamin K antagonist drugs, bu
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https://en.wikipedia.org/wiki/Nuclear%20War%20Survival%20Skills
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Nuclear War Survival Skills or NWSS, by Cresson Kearny, is a civil defense manual. It contains information gleaned from research performed at Oak Ridge National Laboratory during the Cold War, as well as from Kearny's extensive jungle living and international travels.
Nuclear War Survival Skills aims to provide a general audience with advice on how to survive conditions likely to be encountered in the event of a nuclear catastrophe, as well as encouraging optimism in the face of such a catastrophe by asserting the survivability of a nuclear war.
The 2022 edition is entitled "Nuclear War Survival Skills Updated and Expanded 2022 Edition Regarding Ukraine Russia and the World: The Best Book on Any Nuclear Incident Ever ... New Methods and Tools As New Threat Emerge".
Overview
The main chapters are preceded by forewords from Edward Teller and Eugene Wigner. Following this is an introduction which explains that even the fruition of the Strategic Defense Initiative program would not make "self-help civil defense" obsolete. A comparison is made of the civil defense preparations of Switzerland, Russia, and the United States, where it is concluded that: "Switzerland has the best civil defense system"; "The rulers of the Soviet Union... continue to prepare the Russians to fight, survive, and win all types of wars"; and that "the United States has advocated... a strategy that purposely leaves its citizens unprotected hostages to its enemies." Thus, "The emphasis in this book is on survival preparations that can be made in the last few days of a worsening crisis."
The Dangers from Nuclear Weapons: Myths and Facts
The first chapter aims to give background information to dispel various demoralizing myths and reaffirm the potential survivability and reality of nuclear weapons. "An all-out nuclear war between Russia and the United States would... be far from the end of human life on earth." Myths listed include: "Fallout radiation from a nuclear war would poison the air and a
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https://en.wikipedia.org/wiki/Tuberculosis%20Structural%20Genomics%20Consortium
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The TB Structural Genomics Consortium (TBSGC) is a worldwide consortium of scientists developing a foundation for tuberculosis diagnosis and treatment by determining the three-dimensional structures of proteins from M. tuberculosis founded in 2000 as a part of the Protein Structure Initiative. The consortium seeks to solve structures of proteins that are of great interest to the TB biology community. A major goal of the consortium is to have a putative function for every ORF in the TB genome.
Activities
As of June 2006, 82 TB protein structures have been determined, 15 since January 1, 2006. The database of linked structural and functional information that has been constructed using this information can form a lasting basis for understanding M. tuberculosis pathogenesis and for structure-based drug design.
As of June 2006, the TB Structural Genomics Consortium consists of 430 active members in 148 laboratories from 83 institutions across 15 countries. Consortium laboratories are collectively responsible for 3.3% of all protein structures in the protein data bank and have extensive records of methods development. Consortium members have carried out a pilot project on the structural genomics of a hyperthermophile that has identified bottlenecks in the structure determination process and resulted in the development of methodologies for high-throughput structure determination and analysis. The consortium has five core facilities (located at Lawrence Livermore National Laboratory, Los Alamos National Lab, Lawrence Berkeley National Laboratory, University of California, Los Angeles and Texas A&M University) that carry out an increasing fraction of routine tasks such as protein production, crystallization and X-ray data collection. Members of the consortium improve their productivity by sending materials to these facilities, receiving the resulting products or data, and reporting this activity to the database. This helps to minimize redundant pursuits of targets. This s
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https://en.wikipedia.org/wiki/Step%20potential
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In quantum mechanics and scattering theory, the one-dimensional step potential is an idealized system used to model incident, reflected and transmitted matter waves. The problem consists of solving the time-independent Schrödinger equation for a particle with a step-like potential in one dimension. Typically, the potential is modeled as a Heaviside step function.
Calculation
Schrödinger equation and potential function
The time-independent Schrödinger equation for the wave function is
where Ĥ is the Hamiltonian, ħ is the reduced Planck constant, m is the mass, E the energy of the particle. The step potential is simply the product of V0, the height of the barrier, and the Heaviside step function:
The barrier is positioned at x = 0, though any position x0 may be chosen without changing the results, simply by shifting position of the step by −x0.
The first term in the Hamiltonian, is the kinetic energy of the particle.
Solution
The step divides space in two parts: x < 0 and x > 0. In any of these parts the potential is constant, meaning the particle is quasi-free, and the solution of the Schrödinger equation can be written as a superposition of left and right moving waves (see free particle)
where subscripts 1 and 2 denote the regions x < 0 and x > 0 respectively, the subscripts (→) and (←) on the amplitudes A and B denote the direction of the particle's velocity vector: right and left respectively.
The wave vectors in the respective regions being
both of which have the same form as the De Broglie relation (in one dimension)
.
Boundary conditions
The coefficients A, B have to be found from the boundary conditions of the wave function at x = 0. The wave function and its derivative have to be continuous everywhere, so:
Inserting the wave functions, the boundary conditions give the following restrictions on the coefficients
Transmission and reflection
It is useful to compare the situation to the classical case. In both cases, the particle behaves as a fr
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