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https://en.wikipedia.org/wiki/Animal%20technology
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Animal technology refers to the practices of keeping, breeding and providing care for animals that are used for scientific purposes, such as captive in a laboratory. Animal technology is one of the recognized professional areas held by registered science technicians, and animal technologists, also called animal technicians, play a key role in supporting biomedical research by ensuring that animals are available for study. Principal areas of animal technology include animal husbandry and breeding, providing day-to-day care for laboratory animals, ensuring compliance with animal welfare practices and legal issues and performing essential scientific procedures. Technical qualifications for animal technologists and the regulations they must adhere to vary by country, but in many parts of the world animal technology is a highly structured profession that forms part of laboratory management. Animal technology is related to the field of animal management and technologists are often specialize in working with particular species of animals, either in the laboratory or in the field.
See also
Technology in veterinary medicine
History of wildlife tracking technology
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https://en.wikipedia.org/wiki/Five-pointed%20star
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A five-pointed star (☆), geometrically an equilateral concave decagon, is a common ideogram in modern culture.
Comparatively rare in classical heraldry, it was notably introduced for the flag of the United States in the Flag Act of 1777 and since has become widely used in flags.
It has also become a symbol of fame or "stardom" in Western culture, among other uses.
History of use
Early history
The Egyptian hieroglyph representing "star" had five points (N14 N14), while the "star" sign in Mesopotamian cuneiform had eight. Sopdet, the Egyptian personification of the star Sirius, is always shown with the five-pointed star hieroglyph on her head.
The star (or mullet) is comparatively rare in medieval heraldry, but from an early time, the five-pointed star was preferred in English and Scottish heraldry (e.g. in the Dering Roll, c. 1270), while the preferred number of points in German heraldry was six.
The star in the coat of arms of the De Vere family was in legend attributed to the First Crusade, when
"a white star [...] did light and arrest upon the standard of Aubre de Vere".
The de Vere star is notorious in English history, because in the Battle of Barnet in 1471, the star badge of the Earl of Oxford was mistaken for the sun badge of Edward IV by the Earl of Warwick, so that he erroneously attacked his own ally, losing the battle, which probably changed the outcome of the entire War of the Roses.
Modern flags and emblems
The five-pointed stars on the flag of the United States were introduced in the Flag Act of 1777.
The Flag Act did not specify any particular arrangement, number of points, nor orientation for the stars and the arrangement. Some flag makers arranged the stars into one big star, in a circle or in rows and some replaced a state's star with its initial. One arrangement features 13 five-pointed stars arranged in a circle, with the stars arranged pointing outwards from the circle (as opposed to up), the so-called Betsy Ross flag.
The American flag
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https://en.wikipedia.org/wiki/List%20of%20Chilean%20flags
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This is a list of flags used in Chile. For more information about the national flag, visit the article Flag of Chile.
National flags
Presidential standard
Ambassador flag
Military flags
Chilean Army
Chilean Navy
Chilean Air Force
Police flags
Vexillology Association flags
Regions
Unofficial regional flags
Communes
Political flags
Indigenous groups flags
Mapuche territories
Historical flags
House flags of Chilean freight companies
Burgees of Chile
Antarctic base flags
Political flags
Sources
The Flags of Chile. Flags of the World
National symbols of Chile. Chilean Government Official Website
Orígenes, mitos y hechos interesantes sobre los símbolos patrios chilenos
Decree 1534 of 1967 about National Symbols of Chile
Reino de Araucanía y Patagonia - Portal Mapuche
Chile
Flags of Chile
Flags
Chilean culture
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https://en.wikipedia.org/wiki/Solar%20plage
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A plage is a bright region in the Sun's chromosphere, typically found in and around active regions. Historically, they have been referred to as bright flocculi, in contrast to dark flocculi, and as chromospheric faculae, in contrast to photospheric faculae.
Etymology
The term is often believed to be poetically taken from the French word for "beach"; however, this is likely a misunderstanding of an 1893 article by Henri-Alexandre Deslandres where the name facular flames was suggested. In the article, Deslandres also refers to them as plages brillantes, meaning bright regions, which became the more commonly used term.
Description
Classically plage have been defined as regions that are bright in Hα and other chromospheric emission lines. but nowadays most researchers identify plage based on the photospheric magnetic field concentration of the faculae below. The magnetic field of plage is confined to the intergranular lanes in the photosphere with a strength of around 1500 G, but expands into a volume filling canopy in the chromosphere with a field of around 450G.
It is believed that plage is formed from decaying emerging flux regions, and often acts as a footprint for coronal loops and fibrils, which makes them an important interface for coronal heating.
See also
Solar cycle
Solar spicule
Solar granule
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https://en.wikipedia.org/wiki/Pastry%20%28DHT%29
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Pastry is an overlay network and routing network for the implementation of a distributed hash table (DHT) similar to Chord. The key–value pairs are stored in a redundant peer-to-peer network of connected Internet hosts. The protocol is bootstrapped by supplying it with the IP address of a peer already in the network and from then on via the routing table which is dynamically built and repaired. It is claimed that because of its redundant and decentralized nature there is no single point of failure and any single node can leave the network at any time without warning and with little or no chance of data loss. The protocol is also capable of using a routing metric supplied by an outside program, such as ping or traceroute, to determine the best routes to store in its routing table.
Overview
Although the distributed hash table functionality of Pastry is almost identical to other DHTs, what sets it apart is the routing overlay network built on top of the DHT concept. This allows Pastry to realize the scalability and fault tolerance of other networks, while reducing the overall cost of routing a packet from one node to another by avoiding the need to flood packets. Because the routing metric is supplied by an external program based on the IP address of the target node, the metric can be easily switched to shortest hop count, lowest latency, highest bandwidth, or even a general combination of metrics.
The hash table's key-space is taken to be circular, like the key-space in the Chord system, and node IDs are 128-bit unsigned integers representing position in the circular key-space. Node IDs are chosen randomly and uniformly so peers who are adjacent in node ID are geographically diverse. The routing overlay network is formed on top of the hash table by each peer discovering and exchanging state information consisting of a list of leaf nodes, a neighborhood list, and a routing table. The leaf node list consists of the L/2 closest peers by node ID in each direction around
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https://en.wikipedia.org/wiki/Comparison%20of%20open-source%20wireless%20drivers
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Wireless network cards for computers require control software to make them function (firmware, device drivers). This is a list of the status of some open-source drivers for 802.11 wireless network cards.
Linux
Status
Driver capabilities
DragonFly BSD
FreeBSD
Status
Driver capabilities
NetBSD
OpenBSD
The following is an incomplete list of supported wireless devices:
Status
Driver capabilities
Solaris and OpenSolaris
Darwin, OpenDarwin and macOS
Notes
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https://en.wikipedia.org/wiki/Stress%20relaxation
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In materials science, stress relaxation is the observed decrease in stress in response to strain generated in the structure. This is primarily due to keeping the structure in a strained condition for some finite interval of time hence causing some amount of plastic strain. This should not be confused with creep, which is a constant state of stress with an increasing amount of strain.
Since relaxation relieves the state of stress, it has the effect of also relieving the equipment reactions. Thus, relaxation has the
same effect as cold springing, except it occurs over a longer period of time.
The amount of relaxation which takes place is a function of time, temperature and stress level, thus the actual effect it has on the system is not precisely known, but can be bounded.
Stress relaxation describes how polymers relieve stress under constant strain. Because they are viscoelastic, polymers behave in a nonlinear, non-Hookean fashion. This nonlinearity is described by both stress relaxation and a phenomenon known as creep, which describes how polymers strain under constant stress. Experimentally, stress relaxation is determined by step strain experiments, i.e. by applying a sudden one-time strain and measuring the build-up and subsequent relaxation of stress in the material (see figure), in either extensional or shear rheology.
Viscoelastic materials have the properties of both viscous and elastic materials and can be modeled by combining elements that represent these characteristics. One viscoelastic model, called the Maxwell model predicts behavior akin to a spring (elastic element) being in series with a dashpot (viscous element), while the Voigt model places these elements in parallel. Although the Maxwell model is good at predicting stress relaxation, it is fairly poor at predicting creep. On the other hand, the Voigt model is good at predicting creep but rather poor at predicting stress relaxation (see viscoelasticity).
The extracellular matrix and most tissu
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https://en.wikipedia.org/wiki/Stirling%20radioisotope%20generator
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A Stirling radioisotope generator (SRG) is a type of radioisotope generator based on a Stirling engine powered by a large radioisotope heater unit. The hot end of the Stirling converter reaches high temperature and heated helium drives the piston, with heat being rejected at the cold end of the engine. A generator or alternator converts the motion into electricity. Given the very constrained supply of plutonium, the Stirling converter is notable for producing about four times as much electric power from the plutonium fuel as compared to a radioisotope thermoelectric generator (RTG).
The Stirling generators were extensively tested on Earth by NASA, but their development was cancelled in 2013 before they could be deployed on actual spacecraft missions. A similar NASA project still under development, called Kilopower, also utilizes Stirling engines, but uses a small uranium fission reactor as the heat source.
History
Stirling and Brayton-cycle technology development has been conducted at NASA Glenn Research Center (formerly NASA Lewis) since the early 1970s. The Space Demonstrator Engine (SPDE) was the earliest 12.5 kWe per cylinder engine that was designed, built and tested. A later engine of this size, the Component Test Power Converter (CTPC), used a "Starfish" heat-pipe heater head, instead of the pumped-loop used by the SPDE. In the 1992-93 time period, this work was stopped due to the termination of the related SP-100 nuclear power system work and NASA's new emphasis on "better, faster, cheaper" systems and missions.
In 2020, a free-piston Stirling power converter reached 15 years of maintenance-free and degradation-free cumulative operation in the Stirling Research Laboratory at NASA Glenn. This duration equals the operational design life of the MMRTG, and is representative of typical mission concepts designed to explore the outer planets or even more distant Kuiper Belt Objects. This unit, called the Technology Demonstration Converter (TDC) #13, is the old
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https://en.wikipedia.org/wiki/Crossed%20ladders%20problem
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The crossed ladders problem is a puzzle of unknown origin that has appeared in various publications and regularly reappears in Web pages and Usenet discussions.
The problem
Two ladders of lengths a and b lie oppositely across an alley, as shown in the figure. The ladders cross at a height of h above the alley floor. What is the width of the alley?
Martin Gardner presents and discusses the problem in his book of mathematical puzzles published in 1979 and cites references to it as early as 1895. The crossed ladders problem may appear in various forms, with variations in name, using various lengths and heights, or requesting unusual solutions such as cases where all values are integers. Its charm has been attributed to a seeming simplicity which can quickly devolve into an "algebraic mess" (characterization attributed by Gardner to D. F. Church).
Solution
The problem description implies that that and , that and that where A and B are the heights of the walls where sides of lengths b and a respectively lean (as in the above graph).
Both solution methods below rely on the property that , , and satisfy the optic equation, i.e. , which can be seen as follows:
Divide the baseline into two parts at the point where it meets , and call the left and right parts and respectively. The angle where meets is common to two similar triangles with bases and respectively. The angle where meets is common to two similar triangles with bases and respectively. This tells us that
which we can then re-arrange (using ) to get
First method
Two statements of the Pythagorean theorem (see figure above)
and
can be subtracted one from the other to eliminate w, and the result can be combined with with alternately A or B solved out to yield the quartic equations
These can be solved algebraically or numerically for the wall heights A and B, and the Pythagorean theorem on one of the triangles can be used to solve for the width w.
Second method
The problem m
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https://en.wikipedia.org/wiki/WISPr
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WISPr (pronounced "whisper") or Wireless Internet Service Provider roaming is a draft protocol submitted to the Wi-Fi Alliance that allows users to roam between wireless internet service providers in a fashion similar to that which allows cellphone users to roam between carriers. A RADIUS server is used to authenticate the subscriber's credentials.
It covers best practices for authenticating users via 802.1X or the Universal Access Method (UAM), the latter being another name for browser-based login at a captive portal hotspot. It requires that RADIUS be used for AAA and defines the required RADIUS attributes. For authentication by smart-clients, Appendix D defines the Smart Client to Access Gateway Interface Protocol, which is an XML-based protocol for authentication. Smart-client software (and devices that use it) use this so-called WISPr XML to seamlessly login to HotSpots without the need for the user to interact with a captive portal.
The draft WISPr specification is no longer available from the Wi-Fi Alliance. It was submitted in a manner that does not conform with current IPR policies within the Wi-Fi Alliance.
Intel and others have started a similar proposal — IRAP, which has now been rolled into ETSI Telecommunications and Internet converged Services and Protocols for Advanced Networking (TISPAN); TS 183 019 and TS 183 020.
The WISPr 2.0 specification was published by the Wireless Broadband Alliance in March 2010.
See also
IEEE 802.11
Wireless Internet service provider
ETSI
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https://en.wikipedia.org/wiki/Data%20and%20object%20carousel
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In digital video broadcasting (DVB), a data and object carousel is used for repeatedly delivering data in a continuous cycle. Carousels allow data to be pushed from a broadcaster to multiple receivers by transmitting a data set repeatedly in a standard format. A set-top box receiver may tune to the data stream at any time and is able to reconstitute the data into a virtual file system. The carousel may therefore be considered as a transport file system or file broadcasting system that allows data files to be transmitted from the broadcaster to multiple receivers or clients simultaneously.
In a unidirectional broadcast environment, the receiver is unable to request the retransmission of any data that was missed or received incorrectly. Repeated retransmission of data allows the receiver to cope with random tuning to a channel at an unpredictable time, for instance as the user changes a channel.
The carousel cycle period generally determines the maximum time required for a receiver to acquire an application or specific datum. It is possible to reduce the access time for commonly used files by broadcasting some data more often than others.
An individual object carousel is also called a service domain in some documents. To be precise, a service domain is a group of related DSM-CC objects. In broadcast systems, there is no difference between an object carousel and a service domain except for the terminology: an object carousel is a service domain, and vice versa.
Usage and applications
Data and object carousels are most commonly used in DVB, which has standards for broadcasting digital television content using carousels. The standard format for a carousel is defined in the Digital Storage Media Command and Control (DSM-CC) toolkit in ISO/IEC 13818-6 and is part of the Digital Audio Video Council (DAVIC) DVB standard for digital video broadcasting. The specification provides support for a variety of communication models, including provision for interactive transport
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https://en.wikipedia.org/wiki/Ribonuclease%20inhibitor
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Ribonuclease inhibitor (RI) is a large (~450 residues, ~49 kDa), acidic (pI ~4.7), leucine-rich repeat protein that forms extremely tight complexes with certain ribonucleases. It is a major cellular protein, comprising ~0.1% of all cellular protein by weight, and appears to play an important role in regulating the lifetime of RNA.
RI has a surprisingly high cysteine content (~6.5%, cf. 1.7% in typical proteins) and is sensitive to oxidation. RI is also rich in leucine (21.5%, compared to 9% in typical proteins) and commensurately lower in other hydrophobic residues, esp. valine, isoleucine, methionine, tyrosine, and phenylalanine.
Structure
RI is the classic leucine-rich repeat protein, consisting of alternating α-helices and β-strands along its backbone. These secondary structure elements wrap around in a curved, right-handed solenoid that resembles a horseshoe. The parallel β-strands and α-helices form the inner and outer wall of the horseshoe, respectively. The structure appears to be stabilized by buried asparagines at the base of each turn, as it passes from α-helix to β-strand. The αβ repeats alternate between 28 and 29 residues in length, effectively forming a 57-residue unit that corresponds to its genetic structure (each exon codes for a 57-residue unit).
Binding to ribonucleases
The affinity of RI for ribonucleases is among the highest for any protein-protein interaction; the dissociation constant of the RI-RNase A complex is in the femtomolar (fM) range under physiological conditions. Despite this high affinity, RI is able to bind a wide variety of RNases A despite their relatively low sequence identity. Both biochemical studies and crystallographic structures of RI-RNase A complexes suggest that the interaction is governed largely by electrostatic interactions, but also involves substantial buried surface area. RI's affinity for ribonucleases is important, since many ribonucleases have cytotoxic and cytostatic effects that correlate well with
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https://en.wikipedia.org/wiki/Abram%20Lyle
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Abram Lyle (14 December 1820 – 30 April 1891) was a Scottish food manufacturer and politician, who is noted for founding the sugar refiners Abram Lyle & Sons in 1887, which merged with the company of his rival Henry Tate to become Tate & Lyle in 1921.
Early life
He was born on 14 December 1820 in the seaport of Greenock, Renfrewshire, in Scotland, and at twelve years old became an apprentice in a lawyer's office. He then joined his father's cooperage businesses and in partnership with a friend, John Kerr, developed a shipping business, making the Lyle fleet one of the largest in Greenock. The area was heavily involved in the sugar trade with the West Indies, and his business included transporting sugar.
Sugar refining
Together with four partners he purchased the sugar house of the defunct Greenock Sugar Refining Company in 1865, forming the Glebe Sugar Refinery Company, and so added sugar refining to his other business interests. When John Kerr, the principal partner, died in 1872, Lyle sold his shares and began the search for a site for a new refinery.
Together with his three sons he bought two wharves at Plaistow in East London in 1881 to construct a refinery for producing golden syrup. The site happened to be around from the sugar refinery of his rival, Henry Tate. In the first year Lyle's refinery showed a loss of £30,000, with economies being made by asking staff to wait for their wages on occasion, but eventually the business came to dominate the United Kingdom market for golden syrup. Lyle Park, near the site of the syrup refinery at Plaistow Wharf, West Silvertown, was named after him.
Out of the strong came forth sweetness
The brand, sold in a distinctive green and gold lidded tin with an image of a lion surrounded by bees, is believed to be Britain's oldest. The design of the tin decoration, which includes a biblical quotation, has remained almost unchanged since 1885.
In the Book of Judges, Samson was travelling to the land of the Philistines i
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https://en.wikipedia.org/wiki/Conjugate%20coding
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Conjugate coding is a cryptographic tool, introduced by Stephen Wiesner in the late 1960s. It is part of the two applications Wiesner described for quantum coding, along with a method for creating fraud-proof banking notes. The application that the concept was based on was a method of transmitting multiple messages in such a way that reading one destroys the others. This is called quantum multiplexing and it uses photons polarized in conjugate bases as "qubits" to pass information. Conjugate coding also is a simple extension of a random number generator.
At the behest of Charles Bennett, Wiesner published the manuscript explaining the basic idea of conjugate coding with a number of examples but it was not embraced because it was significantly ahead of its time. Because its publication has been rejected, it was developed to the world of public-key cryptography in the 1980s as Oblivious Transfer, first by Michael Rabin and then by Shimon Even. It is used in the field of quantum computing. The initial concept of quantum cryptography developed by Bennett and Gilles Brassard was also based on this concept.
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https://en.wikipedia.org/wiki/MSX-DOS
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MSX-DOS is a discontinued disk operating system developed by Microsoft for the 8-bit home computer standard MSX, and is a cross between MS-DOS v1.25 and CP/M-80 v2.2.
MSX-DOS
MSX-DOS and the extended BASIC with 3½-inch floppy disk support were simultaneously developed by Microsoft and ASCII Corporation as a software and hardware standard for the MSX home computer standard, to add disk capabilities to BASIC and to give the system a cheaper software medium than Memory Cartridges, and a more powerful storage system than cassette tape. The standard BIOS of an unexpanded MSX computer had no built-in disk support, but provided hooks for a disk extension, so the additional floppy disk expansion system came with its own BIOS extension ROM (built-in on the disk controller) called the BDOS.
This BIOS not only added floppy disk support commands to MSX BASIC, but also a booting system, with which it was possible to boot a real disk operating system.
MSX-DOS was binary compatible with CP/M-80, allowing the MSX computer to easily have access to its vast library of software available for a very small cost for the time.
Boot processing
Once MSX-DOS has been loaded, the system searches the MSX-DOS disk for the COMMAND.COM file and loads it into memory. In that case, the BDOS bypassed the BASIC ROMs, so that the whole 64 KB of address space of the Z80 microprocessor inside the MSX computer could be used for the DOS or for other boot-able disks, for example disk based games. At the same time, the original BIOS ROMs could still be accessed through a "memory bank switch" mechanism, so that DOS-based software could still use BIOS calls to control the hardware and other software mechanisms the main ROMs supplied. Also, due to the BDOS ROM, basic file access capabilities were available even without a command interpreter by using extended BASIC commands.
At initial startup, COMMAND.COM looks for an optional batch file named AUTOEXEC.BAT and, if it exists, executes the commands specif
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https://en.wikipedia.org/wiki/Intermittent%20photic%20stimulation
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In medicine, Intermittent Photic Stimulation, or IPS, is a form of visual stimulation used in conjunction with electroencephalography to investigate anomalous brain activity triggered by specific visual stimuli, such as flashing lights or patterns.
IPS and EEGs are often used to diagnose conditions such as photosensitive epilepsy. The field is relatively new and the details of use of IPS have not been widely standardized. IPS is often used in conjunction with other controllable generators of visual stimuli, such as low-level visual stimulation LLVS.
Photic stimulation may also be used to elicit myoclonus, especially cortical reflex myoclonus when present in photo-sensitive forms.
IPS may be used to stimulate the visual system for patients with amblyopia. This system uses a visual stimulus that is usually red in color with a frequency of about 4 Hz to stimulate the neural pathway between the retina and the visual cortex. The objective is to improve the visual acuity of an amblyopic (lazy) eye.
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https://en.wikipedia.org/wiki/Variable%20Assembly%20Language
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Variable Assembly Language (VAL) is a computer-based control system and language designed specifically for use with Unimation Inc. industrial robots.
The VAL robot language is permanently stored as a part of the VAL system. This includes the programming language used to direct the system for individual applications. The VAL language has an easy to understand syntax. It uses a clear, concise, and generally self-explanatory instruction set. All commands and communications with the robot consist of easy to understand word and number sequences. Control programs are written on the same computer that controls the robot. As a real-time system, VAL's continuous trajectory computation permits complex motions to be executed quickly, with efficient use of system memory and reduction in overall system complexity. The VAL system continuously generates robot control commands, and can simultaneously interact with a human operator, permitting on-line program generation and modification.
A convenient feature or VAL is the ability to use libraries or manipulation routines. Thus, complex operations may be easily and quickly programmed by combining predefined subtasks.
The VAL language consists of monitor commands and program instructions.
The monitor commands are used to prepare the system for execution of user-written programs. Program instructions provide the repertoire necessary to create VAL programs for controlling robot actions.
Terminology
The following terms are frequently used in VAL related operations.
Monitor
The VAL monitor is an administrative computer program that oversees operation of a system. It accepts user input and initiates the appropriate response; follows instructions from user-written programs to direct the robot; and performs the computations necessary to control the robot.
Editor
The VAL editor is an aid for entering information into a computer system, and modifying existing text. It is used to enter and modify robot control programs. It has a list of i
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https://en.wikipedia.org/wiki/Computational%20mechanics
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Computational mechanics is the discipline concerned with the use of computational methods to study phenomena governed by the principles of mechanics. Before the emergence of computational science (also called scientific computing) as a "third way" besides theoretical and experimental sciences, computational mechanics was widely considered to be a sub-discipline of applied mechanics. It is now considered to be a sub-discipline within computational science.
Overview
Computational mechanics (CM) is interdisciplinary. Its three pillars are mechanics, mathematics, and computer science and physics.
Mechanics
Computational fluid dynamics, computational thermodynamics, computational electromagnetics, computational solid mechanics are some of the many specializations within CM.
Mathematics
The areas of mathematics most related to computational mechanics are partial differential equations, linear algebra and numerical analysis. The most popular numerical methods used are the finite element, finite difference, and boundary element methods in order of dominance. In solid mechanics finite element methods are far more prevalent than finite difference methods, whereas in fluid mechanics, thermodynamics, and electromagnetism, finite difference methods are almost equally applicable. The boundary element technique is in general less popular, but has a niche in certain areas including acoustics engineering, for example.
Computer Science
With regard to computing, computer programming, algorithms, and parallel computing play a major role in CM. The most widely used programming language in the scientific community, including computational mechanics, is Fortran. Recently, C++ has increased in popularity. The scientific computing community has been slow in adopting C++ as the lingua franca. Because of its very natural way of expressing mathematical computations, and its built-in visualization capacities, the proprietary language/environment MATLAB is also widely used, especially for ra
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https://en.wikipedia.org/wiki/Virosome
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A virosome is a drug or vaccine delivery mechanism consisting of unilamellar phospholipid membrane (either a mono- or bi-layer) vesicle incorporating virus derived proteins to allow the virosomes to fuse with target cells. Viruses are infectious agents that can replicate in their host organism, however virosomes do not replicate. The properties that virosomes share with viruses are based on their structure; virosomes are essentially safely modified viral envelopes that contain the phospholipid membrane and surface glycoproteins. As a drug or vaccine delivery mechanism they are biologically compatible with many host organisms and are also biodegradable. The use of reconstituted virally derived proteins in the formation of the virosome allows for the utilization of what would otherwise be the immunogenic properties of a live-attenuated virus, but is instead a safely killed virus. A safely killed virus can serve as a promising vector because it won't cause infection and the viral structure allows the virosome to recognize specific components of its target cells.
Virosomes structure
Virosomes are vehicles that have a spherical shape with a phospholipid mono/bilayer membrane. Inside of the virosome, there is a central cavity that holds the therapeutic molecules such as nucleic acids, proteins, and drugs. On the surface of the virosome, there can be different types of glycoproteins. Glycoproteins are a type of protein that have an oligosaccharide chain bonded to amino acid chains. The different types of glycoproteins on the surface of the virosome increases the specificity of the target cells because the surface glycoproteins help with recognition as well as the attachments of the virosomes to their target cells. In the case of the influenza virosome, the glycoproteins are antigen, haemagglutinin, and neuraminidase. Antigens are molecules that triggers an immune response when targeted by a specific antibody that corresponds to the shape of the antigen. Haemagglutinin is
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https://en.wikipedia.org/wiki/HippoDraw
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HippoDraw is a object-oriented statistical data analysis package written in C++, with user interaction via a Qt-based GUI and a Python-scriptable interface. It was developed by Paul Kunz at SLAC, primarily for the analysis and presentation of particle physics and astrophysics data, but can be equally well used in other fields where data handling is important.
About
HippoDraw can read and write files in an XML-based format, astrophysics FITS files, data objects produced by ROOT (optional), and through the Python bindings, anything that can be read/written by Python (HDF5, for instance, with PyTables).
HippoDraw can be used as a Python extension module, allowing users to use HippoDraw data objects with the full power of the Python language. This includes other scientific Python extension modules such Numeric and numarray, whose use with HippoDraw can lead to a large increase in processing speed, even for ROOT objects.
See also
Java Analysis Studio (JAS)
ROOT
AIDA
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https://en.wikipedia.org/wiki/Max%20Skladanowsky
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Max Skladanowsky (30 April 1863 – 30 November 1939) was a German inventor and early filmmaker. Along with his brother Emil, he invented the Bioscop, an early movie projector the Skladanowsky brothers used to display a moving picture show to a paying audience on 1 November 1895, shortly before the public debut of the Lumière Brothers' Cinématographe in Paris on 28 December 1895.
Career
Born as the fourth child of glazier Carl Theodor Skladanowsky (1830–1897) and Luise Auguste Ernestine Skladanowsky, Max Skladanowsky was apprenticed as a photographer and glass painter, which led to an interest in magic lanterns. In 1879, he began to tour Germany and Central Europe with his father Carl and elder brother Emil, giving dissolving magic lantern shows. While Emil mostly took care of promotion, Max was mostly involved with the technology and for instance developed special multi-lens devices that allowed simultaneous projection of up to nine separate image sequences. Carl retired from this show business, but Max and Emil continued and added other attractions, including a type of naumachia that involved electro-mechanical effects and pyrotechnics.
Max would later claim to have constructed their first film camera on 20 August 1892, but this more likely happened in the summer or autumn of 1894. He also single-handedly constructed the Bioskop projector. Partially based on the dissolving view lantern, it featured two lenses and two separate film reels, one frame being projected alternately from each. It was hand-cranked to transport 44.5mm-wide unperforated Eastman-Kodak film-stock, which was carefully cut, perforated and re-assembled by hand and coated with an emulsion developed by Max. The projector was placed behind a screen, which was made properly transparent by keeping it wet to show the images optimally.
The Skladanowsky brothers shot several films in May 1895. Their first film recorded Emil performing overstated movements on a rooftop with a panorama of Berlin in the
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https://en.wikipedia.org/wiki/Eden%20growth%20model
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The Eden growth model describes the growth of specific types of clusters such as bacterial colonies and deposition of materials. These clusters grow by random accumulation of material on their boundary. These are also an example of a surface fractal. The model, named after Murray Eden, was first described in 1961 as a way of studying biological growth, and was simulated on a computer for clusters up to about 32,000 cells. By the mid-1980s, clusters with a billion cells had been grown, and a slight anisotropy had been observed.
See also
Diffusion-limited aggregation
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https://en.wikipedia.org/wiki/Ansa%20lenticularis
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The ansa lenticularis (ansa lentiformis in older texts) is a part of the brain, making up the superior layer of the substantia innominata. Its fibers, derived from the medullary lamina of the lentiform nucleus, pass medially to end in the thalamus and subthalamic region, while others are said to end in the tegmentum and red nucleus.
It is classified by NeuroNames as part of the subthalamus.
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https://en.wikipedia.org/wiki/Torsion%20constant
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The torsion constant is a geometrical property of a bar's cross-section which is involved in the relationship between angle of twist and applied torque along the axis of the bar, for a homogeneous linear-elastic bar. The torsion constant, together with material properties and length, describes a bar's torsional stiffness. The SI unit for torsion constant is m4.
History
In 1820, the French engineer A. Duleau derived analytically that the torsion constant of a beam is identical to the second moment of area normal to the section Jzz, which has an exact analytic equation, by assuming that a plane section before twisting remains planar after twisting, and a diameter remains a straight line.
Unfortunately, that assumption is correct only in beams with circular cross-sections, and is incorrect for any other shape where warping takes place.
For non-circular cross-sections, there are no exact analytical equations for finding the torsion constant. However, approximate solutions have been found for many shapes.
Non-circular cross-sections always have warping deformations that require numerical methods to allow for the exact calculation of the torsion constant.
The torsional stiffness of beams with non-circular cross sections is significantly increased if the warping of the end sections is restrained by, for example, stiff end blocks.
Partial Derivation
For a beam of uniform cross-section along its length:
where
is the angle of twist in radians
T is the applied torque
L is the beam length
G is the Modulus of rigidity (shear modulus) of the material
J is the torsional constant
Torsional Rigidity (GJ) and Stiffness (GJ/L)
Inverting the previous relation, we can define two quantities: the torsional rigidity,
with SI units N⋅m2/rad
And the torsional stiffness,
with SI units N⋅m/rad
Examples for specific uniform cross-sectional shapes
Circle
where
r is the radius
This is identical to the second moment of area Jzz and is exact.
alternatively write:
where
D is th
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https://en.wikipedia.org/wiki/Illumination%20%28image%29
|
Illumination is an important concept in visual arts.
The illumination of the subject of a drawing or painting is a key element in creating an artistic piece, and the interplay of light and shadow is a valuable method in the artist's toolbox. The placement of the light sources can make a considerable difference in the type of message that is being presented. Multiple light sources can wash out any wrinkles in a person's face, for instance, and give a more youthful appearance. In contrast, a single light source, such as harsh daylight, can serve to highlight any texture or interesting features.
Processing of illumination is an important concept in computer vision and computer graphics.
See also
Chiaroscuro
Artistic techniques
Lighting
Computer graphics
Image processing
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https://en.wikipedia.org/wiki/Beta-propeller
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In structural biology, a beta-propeller (β-propeller) is a type of all-β protein architecture characterized by 4 to 8 highly symmetrical blade-shaped beta sheets arranged toroidally around a central axis. Together the beta-sheets form a funnel-like active site.
Structure
Each beta-sheet typically has four anti-parallel β-strands arranged in the beta-zigzag motif. The strands are twisted so that the first and fourth strands are almost perpendicular to each other. There are five classes of beta-propellers, each arrangement being a highly symmetrical structure with 4–8 beta sheets, all of which generally form a central tunnel that yields pseudo-symmetric axes.
While, the protein's official active site for ligand-binding is formed at one end of the central tunnel by loops between individual beta-strands, protein-protein interactions can occur at multiple areas around the domain. Depending on the packing and tilt of the beta-sheets and beta-strands, the beta-propeller may have a central pocket in place of a tunnel.
The beta-propeller structure is stabilized mainly through hydrophobic interactions of the beta-sheets, while additional stability may come from hydrogen bonds formed between the beta-sheets of the C- and N-terminal ends. In effect this closes the circle which can occur even more strongly in 4-bladed proteins via a disulfide bond. The chaperones Hsp70 and CCT have been shown to sequentially bind nascent beta-propellers as they emerge from the ribosome. These chaperones prevent non-native inter-blade interactions from forming until the entire beta-propeller is synthesized. Many beta-propellers are dependent on CCT for expression. In at least one case, ions have been shown to increase stability by binding deep in the central tunnel of the beta-propeller.
Murzin proposed a geometric model to describe the structural principles of the beta propeller. According to this model the seven bladed propeller was the most favored arrangement in geometric terms.
Despite
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https://en.wikipedia.org/wiki/DictyBase
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dictyBase is an online bioinformatics database for the model organism Dictyostelium discoideum.
Tools
dictyBase offers many ways of searching and retrieving data from the database:
dictyMart - a tool for retrieving varied information on many genes (or the sequences of those genes).
Genome Browser - browse the genes of D. discoideum in their genomic context.
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https://en.wikipedia.org/wiki/TIM%20barrel
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The TIM barrel (triose-phosphate isomerase), also known as an alpha/beta barrel, is a conserved protein fold consisting of eight alpha helices (α-helices) and eight parallel beta strands (β-strands) that alternate along the peptide backbone. The structure is named after triose-phosphate isomerase, a conserved metabolic enzyme. TIM barrels are ubiquitous, with approximately 10% of all enzymes adopting this fold. Further, five of seven enzyme commission (EC) enzyme classes include TIM barrel proteins. The TIM barrel fold is evolutionarily ancient, with many of its members possessing little similarity today, instead falling within the twilight zone of sequence similarity.
The inner beta barrel (β-barrel) is in many cases stabilized by intricate salt-bridge networks. Loops at the C-terminal ends of the β-barrel are responsible for catalytic activity while N-terminal end loops are important for the stability of the TIM-barrels. Structural inserts ranging from extended loops to independent protein domains may be inserted in place of these loops or at the N-terminus/C-terminals. TIM barrels appear to have evolved through gene duplication and domain fusion events of half-barrel proteins, with a majority of TIM barrels originating from a common ancestor. This led many TIM barrels to possess internal symmetries. Further gene duplication events of this ancestral TIM barrel led to diverging enzymes possessing the functional diversity observed today. TIM barrels have also been a longstanding target for protein designers. Successful TIM barrel designs include both domain fusions of existing proteins and de novo designs. Domain fusions experiments have resulted in many successful designs, whereas de novo designs only yielded successes after 28 years of incremental development.
Structure
Topology
The TIM barrel gets its name from the enzyme triose-phosphate isomerase (TIM), which was the first protein possessing the fold to be crystallized. TIM barrels contain 200-250 amino aci
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https://en.wikipedia.org/wiki/DGLAP%20evolution%20equations
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The Dokshitzer–Gribov–Lipatov–Altarelli–Parisi (DGLAP) evolution equations are equations in QCD describing the variation of parton distribution functions with varying energy scales. Experimentally observed scaling violation in deep inelastic scattering is important evidence for the correctness of the equations and of QCD in general. The equations were first published in the western world by Guido Altarelli and Giorgio Parisi in 1977, and so are still sometimes called the Altarelli–Parisi equations. Only later did it become known that an equivalent formula had been published in Russia by in 1977, and by Vladimir Gribov and Lev Lipatov in 1972.
The DGLAP QCD evolution equations are widely used in global determinations of parton distributions, like those from the CTEQ or NNPDF collaborations.
See also
Jet (particle physics)
HERA
APFEL (Software)
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https://en.wikipedia.org/wiki/Megamax%20C
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Megamax C is a K&R C-based development system originally written for Macintosh and ported to the Atari ST and Apple IIGS computers. Sold by Megamax, Inc., based in Richardson, Texas, the package includes a one-pass compiler, linker, text editor, resource construction kit, and documentation. Megamax C was written by Michael Bunnell with Eric Parker providing the linker and most of the standard library. A circa-1988 version of the compiler was renamed Laser C, while the company remained Megamax.
In the early days of the Atari ST, Megamax C was the primary competitor to the Alcyon C compiler from Digital Research included in the official developer kit from Atari Corporation, and the documentation covers Atari-specific features. The company advertised that Megamax C could be used on a 520 ST with a single floppy drive. The ST version includes the source code and assets for Megaroids, a clone of the Asteroids video game, written by Mike Bunnell with sound effects by Mitch Bunnell.
Technical details
On both the Atari ST and Macintosh, the size of a compiled module is limited to 32K of code, and arrays have the same 32K restriction. The limitation stems from a requirement on the Macintosh which was carried over to the Atari. This is despite the Motorola 68000 CPU in both machines having a 24-bit address range.
Reception
According to a review of the Atari ST version in Antic by Mike Fleishman, Megamax C compiled a small benchmark program six times faster than Digital Research's compiler. In a comparison of C compilers for the Atari ST, STart magazine wrote, "For a development compiler, Megamax C is, without question, the best available on the Atari. It will reduce your compile/test turn-around time by at least a factor of five." They also pointed out that the $200 price may be steep for hobbyists and students.
The compiler was used for development by Batteries Included and FTL Games.
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https://en.wikipedia.org/wiki/Harnack%27s%20curve%20theorem
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In real algebraic geometry, Harnack's curve theorem, named after Axel Harnack, gives the possible numbers of connected components that an algebraic curve can have, in terms of the degree of the curve. For any algebraic curve of degree in the real projective plane, the number of components is bounded by
The maximum number is one more than the maximum genus of a curve of degree , attained when the curve is nonsingular. Moreover, any number of components in this range of possible values can be attained.
A curve which attains the maximum number of real components is called an M-curve (from "maximum") – for example, an elliptic curve with two components, such as or the Trott curve, a quartic with four components, are examples of M-curves.
This theorem formed the background to Hilbert's sixteenth problem.
In a recent development a Harnack curve is shown to be a curve whose amoeba has area equal to the Newton polygon of the polynomial , which is called the characteristic curve of dimer models, and every Harnack curve is the spectral curve of some dimer model.()
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https://en.wikipedia.org/wiki/Slowly%20changing%20dimension
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A slowly changing dimension (SCD) in data management and data warehousing is a dimension which contains relatively static data which can change slowly but unpredictably, rather than according to a regular schedule. Some examples of typical slowly changing dimensions are entities such as names of geographical locations, customers, or products.
Some scenarios can cause referential integrity problems.
For example, a database may contain a fact table that stores sales records. This fact table would be linked to dimensions by means of foreign keys. One of these dimensions may contain data about the company's salespeople: e.g., the regional offices in which they work. However, the salespeople are sometimes transferred from one regional office to another. For historical sales reporting purposes it may be necessary to keep a record of the fact that a particular sales person had been assigned to a particular regional office at an earlier date, whereas that sales person is now assigned to a different regional office.
Dealing with these issues involves SCD management methodologies referred to as Type 0 through 6. Type 6 SCDs are also sometimes called Hybrid SCDs.
Type 0: retain original
The Type 0 dimension attributes never change and are assigned to attributes that have durable values or are described as 'Original'. Examples: Date of Birth, Original Credit Score. Type 0 applies to most date dimension attributes.
Type 1: overwrite
This method overwrites old with new data, and therefore does not track historical data.
Example of a supplier table:
In the above example, Supplier_Code is the natural key and Supplier_Key is a surrogate key. Technically, the surrogate key is not necessary, since the row will be unique by the natural key (Supplier_Code).
If the supplier relocates the headquarters to Illinois the record would be overwritten:
The disadvantage of the Type 1 method is that there is no history in the data warehouse. It has the advantage however that it's e
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https://en.wikipedia.org/wiki/Indianapolis%20Prize
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The Indianapolis Prize is a biennial prize awarded by the Indianapolis Zoo to individuals for "extraordinary contributions to conservation efforts" affecting one or more animal species.
Overview
The Indianapolis Prize was established by the Indianapolis Zoo to recognize and reward individuals who have achieved significant successes in the conservation of animal species.
Every two years, nominations of deserving individuals for the Indianapolis Prize are accepted. From those nominations, a group of conservation experts from around the world select six finalists. A second group of conservation experts, aided by representatives from the Indianapolis Zoo and the city of Indianapolis, serve as jurors to review the work of the six finalists and select the winner.
From 2006 through 2012, winners received an unrestricted cash award of US$100,000, which was increased to US$250,000 for 2014 and subsequent years. In addition, beginning in 2023, the five other finalists each receive a US$50,000 unrestricted cash award.
Many renowned conservationists and scientists have served on the nominating committee and jury, including E.O. Wilson, John Terborgh, Peter Raven, and Stuart Pimm. New nominating committee and jury members are chosen each two-year prize cycle.
The Eli Lilly and Company Foundation provides funding for the prize. In addition to the US$250,000 award, the winner also receives the Lilly Medal. The obverse of the Lilly Medal features a shepherd surrounded by nature and the rising sun. On the reverse is inscribed a quote from naturalist John Muir, "When we try to pick out anything by itself, we find it hitched to everything else in the Universe."
Indianapolis Prize Gala
The winner and finalists are celebrated at the Indianapolis Prize Gala held in downtown Indianapolis. It is designed to inspire guests to care more about animal conservation and place these dedicated heroes on the pedestal usually reserved for sports and entertainment stars.
Jane Alexander Global
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https://en.wikipedia.org/wiki/Engineering%20change%20order
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An engineering change order (ECO), also called an engineering change notice (ECN), engineering change (EC), or engineering release notice(ERN), is an artifact used to implement changes to components or end products. The ECO is utilized to control and coordinate changes to product designs that evolve over time.
The need for an engineering change may be triggered by a number of events and varies by industry. Typical engineering change categories are:
Product Evolution - a change resulting in applying an existing part to a new application and maintaining backwards compatibility
Cost Reduction - a change resulting in lower overall cost to produce or maintain
Product Performance - a change that improves the capabilities of the item
Safety - a change required to enhance the safety to those using or interacting with the item
Usage and contents
An ECO is defined as "[A] document approved by the design activity that describes and authorizes the implementation of an engineering change to the product and its approved configuration documentation".
In product development the need for change is caused by:
Correction of a design error that doesn't become evident until testing and modeling, or customer use reveals it.
A change in the customers' requirements necessitating the redesign of part of the product
A change in material or manufacturing method. This can be caused by a lack of material availability, a change in vendor, or to compensate for a design error.
An ECO must contain at least this information:
Identification of what needs to be changed. This should include the part number and name of the component and reference to the drawings that show the component in detail or assembly.
Reason(s) for the change.
Description of the change. This includes a drawing of the component before and after the change. Generally, these drawings are only of the detail affected by the change.
List of documents and departments affected by the change. The most important p
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https://en.wikipedia.org/wiki/Lemniscate
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In algebraic geometry, a lemniscate is any of several figure-eight or -shaped curves. The word comes from the Latin meaning "decorated with ribbons", from the Greek meaning "ribbon", or which alternatively may refer to the wool from which the ribbons were made.
Curves that have been called a lemniscate include three quartic plane curves: the hippopede or lemniscate of Booth, the lemniscate of Bernoulli, and the lemniscate of Gerono. The study of lemniscates (and in particular the hippopede) dates to ancient Greek mathematics, but the term "lemniscate" for curves of this type comes from the work of Jacob Bernoulli in the late 17th century.
History and examples
Lemniscate of Booth
The consideration of curves with a figure-eight shape can be traced back to Proclus, a Greek Neoplatonist philosopher and mathematician who lived in the 5th century AD. Proclus considered the cross-sections of a torus by a plane parallel to the axis of the torus. As he observed, for most such sections the cross section consists of either one or two ovals; however, when the plane is tangent to the inner surface of the torus, the cross-section takes on a figure-eight shape, which Proclus called a horse fetter (a device for holding two feet of a horse together), or "hippopede" in Greek. The name "lemniscate of Booth" for this curve dates to its study by the 19th-century mathematician James Booth.
The lemniscate may be defined as an algebraic curve, the zero set of the quartic polynomial when the parameter d is negative (or zero for the special case where the lemniscate becomes a pair of externally tangent circles). For positive values of d one instead obtains the oval of Booth.
Lemniscate of Bernoulli
In 1680, Cassini studied a family of curves, now called the Cassini oval, defined as follows: the locus of all points, the product of whose distances from two fixed points, the curves' foci, is a constant. Under very particular circumstances (when the half-distance between the points is
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https://en.wikipedia.org/wiki/Sync%20%28Unix%29
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sync is a standard system call in the Unix operating system, which commits all data from the kernel filesystem buffers to non-volatile storage, i.e., data which has been scheduled for writing via low-level I/O system calls. Higher-level I/O layers such as stdio may maintain separate buffers of their own.
As a function in C, the sync() call is typically declared as void sync(void) in <unistd.h>. The system call is also available via a command line utility also called sync, and similarly named functions in other languages such as Perl and Node.js (in the fs module).
The related system call fsync() commits just the buffered data relating to a specified file descriptor. fdatasync() is also available to write out just the changes made to the data in the file, and not necessarily the file's related metadata.
Some Unix systems run a kind of flush or update daemon, which calls the sync function on a regular basis. On some systems, the cron daemon does this, and on Linux it was handled by the pdflush daemon which was replaced by a new implementation and finally removed from the Linux kernel in 2012. Buffers are also flushed when filesystems are unmounted or remounted read-only, for example prior to system shutdown.
Some applications, such as LibreOffice, are also call sync function to save recovery information in an interval.
Database use
In order to provide proper durability, databases need to use some form of sync in order to make sure the information written has made it to non-volatile storage rather than just being stored in a memory-based write cache that would be lost if power failed. PostgreSQL for example may use a variety of different sync calls, including fsync() and fdatasync(), in order for commits to be durable. Unfortunately, for any single client writing a series of records, a rotating hard drive can only commit once per rotation, which makes for at best a few hundred such commits per second. Turning off the fsync requirement can therefore greatly improve
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https://en.wikipedia.org/wiki/CoSign%20single%20sign%20on
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Cosign is an open-source project originally designed by the Research Systems Unix Group to provide the University of Michigan with a secure single sign-on web authentication system.
Cosign authenticates a user on the web server and then provides an environment variable for the user's name. When the user accesses a part of the site that requires authentication, the presence of that variable allows access without having to sign on again.
Cosign is part of the National Science Foundation Middleware Initiative (NMI) EDIT software release.
See also
Central Authentication Service
Pubcookie
Stanford WebAuth
University of Minnesota CookieAuth
Shibboleth (Internet2)
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https://en.wikipedia.org/wiki/David%20Milman
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David Pinhusovich Milman (; 15 January 1912, Chechelnyk near Vinnytsia – 12 July 1982, Tel Aviv) was a Soviet and later Israeli mathematician specializing in functional analysis. He was one of the major figures of the Soviet school of functional analysis. In the 70s he emigrated to Israel and was on the faculty of Tel Aviv University.
Milman is known for his development of functional analysis methods, particularly in operator theory, in close connection with concrete problems coming from mathematical physics, in particular differential equations and normal modes. The Krein–Milman theorem and the Milman–Pettis theorem are named after him.
Milman received his Ph.D. from Odessa State University in 1939 under direction of Mark Krein.
He is the father of the mathematicians Vitali Milman and Pierre Milman; and the grandfather to the mathematician Emanuel Milman and biochemist Pavel Milman.
Notes
External links
1912 births
1982 deaths
20th-century Israeli mathematicians
Ukrainian Jews
20th-century Israeli Jews
Soviet mathematicians
Academic staff of Tel Aviv University
Functional analysts
Soviet emigrants to Israel
Academic staff of K. D. Ushinsky South Ukrainian National Pedagogical University
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https://en.wikipedia.org/wiki/OpenVZ
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OpenVZ (Open Virtuozzo) is an operating-system-level virtualization technology for Linux. It allows a physical server to run multiple isolated operating system instances, called containers, virtual private servers (VPSs), or virtual environments (VEs). OpenVZ is similar to Solaris Containers and LXC.
OpenVZ compared to other virtualization technologies
While virtualization technologies such as VMware, Xen and KVM provide full virtualization and can run multiple operating systems and different kernel versions, OpenVZ uses a single Linux kernel and therefore can run only Linux. All OpenVZ containers share the same architecture and kernel version. This can be a disadvantage in situations where guests require different kernel versions than that of the host. However, as it does not have the overhead of a true hypervisor, it is very fast and efficient.
Memory allocation with OpenVZ is soft in that memory not used in one virtual environment can be used by others or for disk caching. While old versions of OpenVZ used a common file system (where each virtual environment is just a directory of files that is isolated using chroot), current versions of OpenVZ allow each container to have its own file system.
Kernel
The OpenVZ kernel is a Linux kernel, modified to add support for OpenVZ containers. The modified kernel provides virtualization, isolation, resource management, and checkpointing. As of vzctl 4.0, OpenVZ can work with unpatched Linux 3.x kernels, with a reduced feature set.
Virtualization and isolation
Each container is a separate entity, and behaves largely as a physical server would. Each has its own:
Files System libraries, applications, virtualized /proc and /sys, virtualized locks, etc.
Users and groups Each container has its own root user, as well as other users and groups.
Process tree A container only sees its own processes (starting from init). PIDs are virtualized, so that the init PID is 1 as it should be.
Network Virtual network device, which allo
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https://en.wikipedia.org/wiki/Frances%20Spence
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Frances V. Spence ( Bilas; March 2, 1922 – July 18, 2012) was one of the original programmers for the ENIAC (the first electronic digital computer). She is considered one of the first computer programmers in history.
The other five ENIAC programmers were Betty Holberton, Ruth Teitelbaum, Kathleen Antonelli, Marlyn Meltzer, and Jean Bartik.
Early life
She was born Frances V. Bilas in Philadelphia in 1922 and was the second of five sisters. Her parents both held jobs in the education sector, her father as an engineer for the Philadelphia Public School System and her mother as a teacher.
Bilas attended the South Philadelphia High School for Girls and graduated in 1938. She originally attended Temple University, but switched to Chestnut Hill College after being awarded a scholarship. She majored in mathematics with a minor in physics and graduated in 1942. While there, she met Kathleen Antonelli, who later also became an ENIAC programmer.
Personal life
In 1947, she married Homer W. Spence, an Army electrical engineer from the Aberdeen Proving Grounds who had been assigned to the ENIAC project and later became head of the Computer Research Branch. They had three sons (Joseph, Richard, and William).
Frances Spence had continued working on the ENIAC in the years after the war, but shortly after her marriage, she resigned to raise a family.
ENIAC career
The ENIAC project was a classified project by the US Army to construct the first all-electronic digital computer. While its hardware was primarily built by a team of men, its computational development was led by a team of six programmers (called "Computers"), all women from similar backgrounds as Spence. Despite her importance as one of the original programmers of the ENIAC, the role that she and the other female programmers took on was largely downplayed at the time due to the stigma that women were not interested in technology.
Photos of the women working on the computer often went without credit in newspapers at t
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https://en.wikipedia.org/wiki/Trends%20in%20International%20Mathematics%20and%20Science%20Study
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The IEA's Trends in International Mathematics and Science Study (TIMSS) is a series of international assessments of the mathematics and science knowledge of students around the world. The participating students come from a diverse set of educational systems (countries or regional jurisdictions of countries) in terms of economic development, geographical location, and population size. In each of the participating educational systems, a minimum of 4,000 to 5,000 students is evaluated. Contextual data about the conditions in which participating students learn mathematics and science are collected from the students and their teachers, their principals, and their parents via questionnaires.
TIMSS is one of the studies established by IEA aimed at allowing educational systems worldwide to compare students' educational achievement and learn from the experiences of others in designing effective education policy. This assessment was first conducted in 1995, and has been administered every four years thereafter. Therefore, some of the participating educational systems have trend data across assessments from 1995 to 2019. TIMSS assesses 4th and 8th grade students, while TIMSS Advanced assesses students in the final year of secondary school in advanced mathematics and physics.
Definition of Terms
"Eighth grade" in the United States is approximately 13–14 years of age and equivalent to:
Year 9 (Y9) in England and Wales
2nd Year (S2) in Scotland
2nd Year in the Republic of Ireland
1st Year in South Africa
Form 2 in Hong Kong
4ème in France
Year 9 in New Zealand
Form 2 in Malaysia
"Fourth grade" in the United States is approximately equivalent to 9–10 years of age and equivalent to:
Year 5 (Y5) in England and Wales
Primary 6 (P6) in Scotland
Group 6 in the Netherlands
CM1 in France
Fourth Class in the Republic of Ireland
Standard 3 or Year 5 in New Zealand
History
A precursor to TIMSS was the First International Mathematics Study (FIMS) performed in 1964 in 11
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https://en.wikipedia.org/wiki/Art%20in%20Bloom
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The phrase Art In Bloom is often used as the title of various exhibits held annually, usually in spring, in art museums. The phrase was created by a Museum of Fine Arts, Boston, volunteer, Lorraine M. Pitts who also helped found the Danforth Museum in Framingham, MA. The exhibit is composed of traditional visual art pieces and corresponding flower arrangements done by local professional florists and garden club members.
The original exhibit was held in the Museum of Fine Arts in Boston in 1976, where it is held annually; other institutions hosting such displays include the Minneapolis Institute of Arts, the Art Gallery of Greater Victoria, the North Carolina Museum of Art, and the Saint Louis Art Museum in St. Louis, Missouri. Universities such as the University of Missouri's Museum of Art and Archaeology in Columbia, Missouri also hold "Art in Bloom" exhibitions.
External links
Museum of Fine Arts, Boston – Art in Bloom 2007
Minneapolis Institute of Arts – Art in Bloom 2007
Art Gallery of Greater Victoria - Art in Bloom 2007
St. Louis Art Museum – Art in Bloom 2007
University of Missouri–Columbia Museum of Art and Archaeology – Art in Bloom 2007
Art In Bloom Show & Sale 2009 - Hamilton, Ontario, Canada
Visual arts exhibitions
Botanical art
Flower shows
Spring festivals
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https://en.wikipedia.org/wiki/Vacuum%20coffee%20maker
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A vacuum coffee maker brews coffee using two chambers where vapor pressure and gravity produce coffee. This type of coffee maker is also known as vac pot, siphon or syphon coffee maker, and was invented by Loeff of Berlin in the 1830s. These devices have since been used for more than a century in many parts of the world. Design and composition of the vacuum coffee maker varies. The chamber material is borosilicate glass, metal, or plastic, and the filter can be either a glass rod or a screen made of metal, cloth, paper, or nylon. The Napier Vacuum Machine by James Robert Napier, presented in 1840, was an early example of this technique. While vacuum coffee makers generally were excessively complex for everyday use, they were prized for producing a clear brew, and were quite popular until the middle of the twentieth century. Vacuum coffee makers remain popular in some parts of Asia, including Japan and Taiwan. The Bauhaus interpretation of this device can be seen in Gerhard Marcks' coffee maker of 1925.
Workings
A vacuum coffee maker operates as a siphon, where heating and cooling the lower vessel changes the vapor pressure of water in the lower, first pushing the water up into the upper vessel, then allowing the water to fall back down into the lower vessel.
Specifically, once the water in lower chamber is hot enough that its vapor pressure (the pressure exerted by the vapour component of a liquid) exceeds the pressure of a standard atmosphere, some of it begins to boil, turning into water vapor. Since the density of water vapor is about 1/2000 that of liquid water, the mixture of the air and water vapor in the lower chamber quickly expands, and, when the new pressure exceeds atmospheric pressure, pushes the remaining water up the siphon tube into the upper chamber, where it remains so long as the pressure difference between the upper and lower chambers is sufficient to support it (about 1.5 kPa or 0.015 atm). This pressure difference is maintained during brew
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https://en.wikipedia.org/wiki/Immunoglobulin%20domain
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The immunoglobulin domain, also known as the immunoglobulin fold, is a type of protein domain that consists of a 2-layer sandwich of 7-9 antiparallel β-strands arranged in two β-sheets with a Greek key topology, consisting of about 125 amino acids.
The backbone switches repeatedly between the two β-sheets. Typically, the pattern is (N-terminal β-hairpin in sheet 1)-(β-hairpin in sheet 2)-(β-strand in sheet 1)-(C-terminal β-hairpin in sheet 2). The cross-overs between sheets form an "X", so that the N- and C-terminal hairpins are facing each other.
Members of the immunoglobulin superfamily are found in hundreds of proteins of different functions. Examples include antibodies, the giant muscle kinase titin, and receptor tyrosine kinases. Immunoglobulin-like domains may be involved in protein–protein and protein–ligand interactions.
Examples
Human genes encoding proteins containing the immunoglobulin domain include:
A1BG
ACAM
ADAMTSL1
ADAMTSL3
AGER
ALCAM
AMIGO1
AMIGO2
AXL
BCAM
BOC
BSG
BTLA
C10orf72
C20orf102
CADM1
CADM3
CD200
CD22
CD276
CD33
CD4
CDON
CEACAM1
CEACAM16
CEACAM20
CEACAM21
CEACAM5
CEACAM6
CEACAM8
CHL1
CILP
CNTFR
CNTN1
CNTN2
CNTN3
CNTN4
CNTN5
CNTN6
CSF1R
DSCAM
DSCAML1
EMB
F11R
FAIM3
FCAR
FCER1A
FCGR1A
FCGR2A
FCGR2B
FCGR2C
FCGR3A
FCGR3B
FCRH1
FCRH3
FCRH4
FCRL1
FCRL2
FCRL3
FCRL4
FCRL5
FCRL6
FCRLA
FGFR1
FGFR2
FGFR3
FGFR4
FGFRL1
FLT1
FLT3
FLT4
FSTL4
FSTL5
GP6
GPA33
GPR116
GPR125
HEPACAM
HLA-DMA
HLA-DMB
HLA-DQB
HLA-DQB1
HMCN1
HNT
HSPG2
HYST2477
ICAM3
ICAM5
IGHA1
IGHD
IGHE
IGSF10
IGSF11
IGSF2
IGSF21
IGSF3
IGSF9
IL11RA
IL1R1
IL1R2
IL1RAPL1
IL1RAPL2
IL1RL1
IL1RL2
IL6R
JAM2
JAM3
KIR-123FM
KIR2DL1
KIR2DL2
KIR2DL3
KIR2DL4
KIR2DL5A
KIR2DL5B
KIR2DLX
KIR2DS1
KIR2DS2
KIR2DS3
KIR2DS4
KIR2DS5
KIR3DL1
KIR3DL2
KIR3DL3
KIR3DS1
KIT
L1CAM
LAG3
LILRA1
LILRA2
LILRA3
LILRA4
LILRA5
LILRA6
LILRB1
LILRB2
LILRB3
LILRB4
LILRB5
LILRP2
LRIG1
LR
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https://en.wikipedia.org/wiki/Second%20source
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In the electronics industry, a second source is a company that is licensed to manufacture and sell components originally designed by another company (the first source).
It is common for engineers and purchasers to avoid components that are only available from a single source, to avoid the risk that a problem with the supplier would prevent a popular and profitable product from being manufactured. For simple components such as resistors and transistors, this is not usually an issue, but for complex integrated circuits, vendors often react by licensing one or more other companies to manufacture and sell the same parts as second sources. While the details of such licenses are usually confidential, they often involve cross-licensing, so that each company also obtains the right to manufacture and sell parts designed by the other.
Examples
MOS Technology licensed Rockwell and Synertek to second-source the 6502 microprocessor and its support components.
Intel licensed AMD to second-source Intel microprocessors such as the 8086 and its related support components. This second-source agreement is particularly famous for leading to much litigation between the two parties. The agreement gave AMD the rights to second-source later Intel parts, but Intel refused to provide the masks for the 386 to AMD. AMD reverse-engineered the 386, and Intel then claimed that AMD's license to the 386 microcode only allowed AMD to "use" the microcode but not to sell products incorporating it. The courts eventually decided in favor of AMD.
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https://en.wikipedia.org/wiki/Ruby%20%28hardware%20description%20language%29
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Ruby is a hardware description language designed by in 1986 intended to facilitate the notation and development of integrated circuits via relational algebra and functional programming.
It should not be confused with RHDL, a hardware description language based on the 1995 Ruby programming language.
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https://en.wikipedia.org/wiki/Visual%20neuroscience
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Visual neuroscience is a branch of neuroscience that focuses on the visual system of the human body, mainly located in the brain's visual cortex. The main goal of visual neuroscience is to understand how neural activity results in visual perception, as well as behaviors dependent on vision. In the past, visual neuroscience has focused primarily on how the brain (and in particular the Visual Cortex) responds to light rays projected from static images and onto the retina. While this provides a reasonable explanation for the visual perception of a static image, it does not provide an accurate explanation for how we perceive the world as it really is, an ever-changing, and ever-moving 3-D environment. The topics summarized below are representative of this area, but far from exhaustive. To be less topic specific, one can see this textbook for the computational link between neural activities and visual perception and behavior: "Understanding vision: theory, models, and data" , published by Oxford University Press 2014.
Face processing
A recent study using Event-Related Potentials (ERPs) linked an increased neural activity in the occipito-temporal region of the brain to the visual categorization of facial expressions. Results focus on a negative peak in the ERP that occurs 170 milliseconds after the stimulus onset. This action potential, called the N170, was measured using electrodes in the occipito-temporal region, an area already known to be changed by face stimuli. Studying by using the EEG, and ERP methods allow for an extremely high temporal resolution of 4 milliseconds, which makes these kinds of experiments extremely well suited for accurately estimating and comparing the time it takes the brain to perform a certain function. Scientists used classification image techniques, to determine what parts of complex visual stimuli (such as a face) will be relied on when patients are asked to assign them to a category, or emotion. They computed the important feature
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https://en.wikipedia.org/wiki/Methanosarcina%20acetivorans
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Methanosarcina acetivorans is a versatile methane producing microbe which is found in such diverse environments as oil wells, trash dumps, deep-sea hydrothermal vents, and oxygen-depleted sediments beneath kelp beds. Only M. acetivorans and microbes in the genus Methanosarcina use all three known metabolic pathways for methanogenesis. Methanosarcinides, including M. acetivorans, are also the only archaea capable of forming multicellular colonies, and even show cellular differentiation. The genome of M. acetivorans is one of the largest archaeal genomes ever sequenced. Furthermore, one strain of M. acetivorans, M. a. C2A, has been identified to possess an F-type ATPase (unusual for archaea, but common for bacteria, mitochondria and chloroplasts) along with an A-type ATPase.
Metabolism
M. acetivorans has been noted for its ability to metabolize carbon monoxide to form acetate and formate. It can also oxidize carbon monoxide into carbon dioxide. The carbon dioxide can then be converted into methane in a process which M. acetivorans uses to conserve energy. It has been suggested that this pathway may be similar to metabolic pathways used by primitive cells.
However, in the presence of minerals containing iron sulfides, as might have been found in sediments in a primordial environment, acetate would be catalytically converted into acetate thioester, a sulfur-containing derivative. Primitive microbes could obtain biochemical energy in the form of adenosine triphosphate (ATP) by converting acetate thioester back into acetate using PTS and ACK, which would then be converted back into acetate thioester to complete the process. In such an environment, a primitive "protocell" could easily produce energy through this metabolic pathway, excreting acetate as waste. Furthermore, ACK catalyzes the synthesis of ATP directly. Other pathways generate energy from ATP only through complex multi-enzyme reactions involving protein pumps and osmotic imbalances across a membrane.
Hi
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https://en.wikipedia.org/wiki/Cationic%20liposome
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Cationic liposomes are spherical structures that contain positively charged lipids. Cationic liposomes can vary in size between 40 nm and 500 nm, and they can either have one lipid bilayer (monolamellar) or multiple lipid bilayers (multilamellar). The positive charge of the phospholipids allows cationic liposomes to form complexes with negatively charged nucleic acids (DNA, mRNA, and siRNA) through ionic interactions. Upon interacting with nucleic acids, cationic liposomes form clusters of aggregated vesicles. These interactions allow cationic liposomes to condense and encapsulate various therapeutic and diagnostic agents in their aqueous compartment or in their lipid bilayer. These cationic liposome-nucleic acid complexes are also referred to as lipoplexes. Due to the overall positive charge of cationic liposomes, they interact with negatively charged cell membranes more readily than classic liposomes. This positive charge can also create some issues in vivo, such as binding to plasma proteins in the bloodstream, which leads to opsonization. These issues can be reduced by optimizing the physical and chemical properties of cationic liposomes through their lipid composition. Cationic liposomes are increasingly being researched for use as delivery vectors in gene therapy due to their capability to efficiently transfect cells. A common application for cationic liposomes is cancer drug delivery.
History
In the 1960s, Alec D. Bangham discovered liposomes as concentric lipid bilayers surrounding an aqueous center, based on his research at the University of Cambridge Babraham Institute. The first formulations were designed using all natural lipids. In 1987, Philip Felgner published the first approach to using cationic lipids to transfect DNA into cells, based on his research into cationic lipids at Syntex from 1982 to 1988. Felgner introduced the first cationic lipid used for gene delivery, N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride (DOTMA).
Compositi
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https://en.wikipedia.org/wiki/Craps%20principle
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In probability theory, the craps principle is a theorem about event probabilities under repeated iid trials. Let and denote two mutually exclusive events which might occur on a given trial. Then the probability that occurs before equals the conditional probability that occurs given that or occur on the next trial, which is
The events and need not be collectively exhaustive (if they are, the result is trivial).
Proof
Let be the event that occurs before . Let be the event that neither nor occurs on a given trial. Since , and are mutually exclusive and collectively exhaustive for the first trial, we have
and .
Since the trials are i.i.d., we have . Using and solving the displayed equation for gives the formula
.
Application
If the trials are repetitions of a game between two players, and the events are
then the craps principle gives the respective conditional probabilities of each player winning a certain repetition, given that someone wins (i.e., given that a draw does not occur). In fact, the result is only affected by the relative marginal probabilities of winning and ; in particular, the probability of a draw is irrelevant.
Stopping
If the game is played repeatedly until someone wins, then the conditional probability above is the probability that the player wins the game. This is illustrated below for the original game of craps, using an alternative proof.
Craps example
If the game being played is craps, then this principle can greatly simplify the computation of the probability of winning in a certain scenario. Specifically, if the first roll is a 4, 5, 6, 8, 9, or 10, then the dice are repeatedly re-rolled until one of two events occurs:
Since and are mutually exclusive, the craps principle applies. For example, if the original roll was a 4, then the probability of winning is
This avoids having to sum the infinite series corresponding to all the possible outcomes:
Mathematically, we can express the probability of rolling ties f
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https://en.wikipedia.org/wiki/Slutsky%27s%20theorem
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In probability theory, Slutsky’s theorem extends some properties of algebraic operations on convergent sequences of real numbers to sequences of random variables.
The theorem was named after Eugen Slutsky. Slutsky's theorem is also attributed to Harald Cramér.
Statement
Let be sequences of scalar/vector/matrix random elements.
If converges in distribution to a random element and converges in probability to a constant , then
provided that c is invertible,
where denotes convergence in distribution.
Notes:
The requirement that Yn converges to a constant is important — if it were to converge to a non-degenerate random variable, the theorem would be no longer valid. For example, let and . The sum for all values of n. Moreover, , but does not converge in distribution to , where , , and and are independent.
The theorem remains valid if we replace all convergences in distribution with convergences in probability.
Proof
This theorem follows from the fact that if Xn converges in distribution to X and Yn converges in probability to a constant c, then the joint vector (Xn, Yn) converges in distribution to (X, c) (see here).
Next we apply the continuous mapping theorem, recognizing the functions g(x,y) = x + y, g(x,y) = xy, and g(x,y) = x y−1 are continuous (for the last function to be continuous, y has to be invertible).
See also
Convergence of random variables
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https://en.wikipedia.org/wiki/Anomalon
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In physics, an anomalon is a hypothetical type of nuclear matter that shows an anomalously large reactive cross section. They were first noticed in experimental runs in the early 1980s as short tracks in film emulsions or plastic leaf detectors connected to medium-energy particle accelerators. The direction of the tracks demonstrated that they were the results of reactions taking place within the accelerator targets, but they stopped so quickly in the detectors that no obvious explanation for their behavior could be offered. A flurry of theoretical explanations followed, but over time a series of follow-up experiments failed to find strong evidence for the anomalons, and active study of the topic largely ended by the late 1980s.
Description
Early particle accelerators generally consisted of three parts, the accelerator, a metal target, and some sort of detector. Detectors differed depending on the reactions being studied, but one class of inexpensive and useful detectors consisted of a large volume of photographic emulsion, often on individual plates, that would capture the particles as they moved through the stack. As the high-energy community moved to larger accelerators and exotic particles and reactions, new detectors were introduced that worked on different principles. The film technique remains in use today in certain fields; small versions can be flown on balloons, while larger versions can be placed in mines, both in order to capture rare but extremely high-energy cosmic rays.
By the late 1970s and early 1980s a generation of accelerators had been made obsolete by newer machines in terms of being useful for leading edge research. Still useful for other tasks, these older machines were turned to a wide variety of new studies. One particularly active area of research is collisions between higher mass particles, instead of fundamental particles like electrons or protons. Although the total energy of the reaction is the same, or lower, than it would be using l
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https://en.wikipedia.org/wiki/Heat%20Wave%20%28Irving%20Berlin%20song%29
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"Heat Wave" is a popular song written by Irving Berlin for the 1933 musical As Thousands Cheer, and introduced in the show by Ethel Waters.
Film appearances
1938: The song was featured in the film Alexander's Ragtime Band, where it was performed by Ethel Merman.
1946: It was also featured in the film Blue Skies, where it was performed by Olga San Juan.
1954: There's No Business Like Show Business, where it was performed by Marilyn Monroe. (Note: based on the lyrics alone, the Marilyn song is different, and within the film's narrative, Monroe's version is a sexier variant of the original that's "stolen" from Ethel Merman's character).
1954: A snippet of the song can be heard in a medley in the film White Christmas, sung by Bing Crosby and Danny Kaye.
1981: Miss Piggy sings it in The Muppets Go to the Movies.
1993: A snippet of the song can be heard in the film Grumpy Old Men, sung by Ella Fitzgerald.
Notable recordings
There were three chart hits in 1933 by:
Ethel Waters
Glen Gray and the Casa Loma Orchestra – vocal by Mildred Bailey
Meyer Davis – vocal by Charlotte Murray.
Other versions
1934: Sol K. Bright & His Hollywaiians
1952: Lee Wiley on the album Lee Wiley Sings Irving Berlin.
1955: Margaret Whiting for Capitol Records CL14242.
1956: Bing Crosby also recorded the song on his album Bing Sings Whilst Bregman Swings.
1958: Ella Fitzgerald sang the song on her album Ella Fitzgerald Sings the Irving Berlin Songbook.
1961: Enoch Light gave a symphonic treatment of the song, which can be found on the album Stereo 35-MM.
1975: Bing Crosby on his 1975 album At My Time of Life.
1979: James White and the Blacks on the 1979 album Off White.
1995: Patti LuPone and the Hollywood Bowl Orchestra on the album Heatwave: Patti LuPone Sings Irving Berlin.
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https://en.wikipedia.org/wiki/Delay%20%28audio%20effect%29
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Delay is an audio signal processing technique that records an input signal to a storage medium and then plays it back after a period of time. When the delayed playback is mixed with the live audio, it creates an echo-like effect, whereby the original audio is heard followed by the delayed audio. The delayed signal may be played back multiple times, or fed back into the recording, to create the sound of a repeating, decaying echo.
Delay effects range from a subtle echo effect to a pronounced blending of previous sounds with new sounds. Delay effects can be created using tape loops, an approach developed in the 1940s and 1950s and used by artists including Elvis Presley and Buddy Holly.
Analog effects units were introduced in the 1970s; digital effects pedals in 1984; and audio plug-in software in the 2000s.
History
The first delay effects were achieved using tape loops improvised on reel-to-reel audio tape recording systems. By shortening or lengthening the loop of tape and adjusting the read-and-write heads, the nature of the delayed echo could be controlled. This technique was most common among early composers of musique concrète such as Pierre Schaeffer, and composers such as Karlheinz Stockhausen, who had sometimes devised elaborate systems involving long tapes and multiple recorders and playback systems, collectively processing the input of a live performer or ensemble.
American producer Sam Phillips created a slapback echo effect with two Ampex 350 tape recorders in 1954. The effect was used by artists including Elvis Presley (such as on his track "Blue Moon of Kentucky") and Buddy Holly, and became one of Phillips' signatures. Guitarist and instrument designer Les Paul was an early pioneer in delay devices. According to Sound on Sound, "The character and depth of sound that was produced from tape echo on these old records is extremely lush, warm and wide."
Tape echoes became commercially available in the 1950s. Tape echo machines contain loops of tape tha
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https://en.wikipedia.org/wiki/Rating%20scale
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Concerning rating scales as systems of educational marks, see more articles about education in different countries (named "Education in ..."), for example, Education in Ukraine.
Concerning rating scales used in the practice of medicine, see articles about diagnoses, for example, Major depressive disorder.
A rating scale is a set of categories designed to elicit information about a quantitative or a qualitative attribute. In the social sciences, particularly psychology, common examples are the Likert response scale and 1-10 rating scales in which a person selects the number that is considered to reflect the perceived quality of a product.
Background
A rating scale is a method that requires the rater to assign a value, sometimes numeric, to the rated object, as a measure of some rated attribute
Types of rating scales
All rating scales can be classified into one of these types:
Numeric Rating Scale (NRS)
Verbal Rating Scale (VRS)
Visual Analogue Scale (VAS)
Likert
Graphic rating scale
Descriptive graphic rating scale
Some data are measured at the ordinal level. Numbers indicate the relative position of items, but not the magnitude of difference. Attitude and opinion scales are usually ordinal; one example is a Likert response scale:
Statement e.g. "I could not live without my computer".
Response options
Strongly disagree
Disagree
Neutral
Agree
Strongly agree
Some data are measured at the interval level. Numbers indicate the magnitude of difference between items, but there is no absolute zero point. A good example is a Fahrenheit/Celsius temperature scale where the differences between numbers matter, but placement of zero does not.
Some data are measured at the ratio level. Numbers indicate magnitude of difference and there is a fixed zero point. Ratios can be calculated. Examples include age, income, price, costs, sales revenue, sales volume and market share.
More than one rating scale question is required to measure an attitude or perception d
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https://en.wikipedia.org/wiki/Acridine%20orange
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Acridine orange is an organic compound that serves as a nucleic acid-selective fluorescent dye with cationic properties useful for cell cycle determination. Acridine orange is cell-permeable, which allows the dye to interact with DNA by intercalation, or RNA via electrostatic attractions. When bound to DNA, acridine orange is very similar spectrally to an organic compound known as fluorescein. Acridine orange and fluorescein have a maximum excitation at 502nm and 525 nm (green). When acridine orange associates with RNA, the fluorescent dye experiences a maximum excitation shift from 525 nm (green) to 460 nm (blue). The shift in maximum excitation also produces a maximum emission of 650 nm (red). Acridine orange is able to withstand low pH environments, allowing the fluorescent dye to penetrate acidic organelles such as lysosomes and phagolysosomes that are membrane-bound organelles essential for acid hydrolysis or for producing products of phagocytosis of apoptotic cells. Acridine orange is used in epifluorescence microscopy and flow cytometry. The ability to penetrate the cell membranes of acidic organelles and cationic properties of acridine orange allows the dye to differentiate between various types of cells (i.e., bacterial cells and white blood cells). The shift in maximum excitation and emission wavelengths provides a foundation to predict the wavelength at which the cells will stain.
Optical properties
When the pH of the environment is 3.5, acridine orange becomes excited by blue light (460 nm). When acridine orange is excited by blue light, the fluorescent dye can differentially stain human cells green and prokaryotic cells orange (600 nm), allowing for rapid detection with a fluorescent microscope. The differential staining capability of acridine orange provides quick scanning of specimen smears at lower magnifications of 400x compared to Gram stains that operate at 1000x magnification. The differentiation of cells is aided by a dark background that allow
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https://en.wikipedia.org/wiki/Partial%20fractions%20in%20complex%20analysis
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In complex analysis, a partial fraction expansion is a way of writing a meromorphic function as an infinite sum of rational functions and polynomials. When is a rational function, this reduces to the usual method of partial fractions.
Motivation
By using polynomial long division and the partial fraction technique from algebra, any rational function can be written as a sum of terms of the form , where and are complex, is an integer, and is a polynomial. Just as polynomial factorization can be generalized to the Weierstrass factorization theorem, there is an analogy to partial fraction expansions for certain meromorphic functions.
A proper rational function (one for which the degree of the denominator is greater than the degree of the numerator) has a partial fraction expansion with no polynomial terms. Similarly, a meromorphic function for which goes to 0 as goes to infinity at least as quickly as has an expansion with no polynomial terms.
Calculation
Let be a function meromorphic in the finite complex plane with poles at and let be a sequence of simple closed curves such that:
The origin lies inside each curve
No curve passes through a pole of
lies inside for all
, where gives the distance from the curve to the origin
one more condition of compatibility with the poles , described at the end of this section
Suppose also that there exists an integer such that
Writing for the principal part of the Laurent expansion of about the point , we have
if . If , then
where the coefficients are given by
should be set to 0, because even if itself does not have a pole at 0, the residues of at must still be included in the sum.
Note that in the case of , we can use the Laurent expansion of about the origin to get
so that the polynomial terms contributed are exactly the regular part of the Laurent series up to .
For the other poles where , can be pulled out of the residue calculations:
To avoid issues with convergence, the poles sh
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https://en.wikipedia.org/wiki/Majesty%20of%20the%20Seas%20%28mini%29
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The mini Majesty of the Seas is a model ship constructed in Morsbach, France, by François Zanella.
The vessel is a 1/8th scale model of Royal Caribbean International's 1992 cruise ship, Majesty of the Seas (also built in France, by Chantiers de l'Atlantique). The mini Majesty is 33.5 metres in length, with a width of 4.75 metres and a draft of 1.06 metres. The model has a displacement of 90 tons. In addition to being a scale replica model, the mini Majesty is a fully functional canal boat. The vessel's draft is small enough to permit admittance to most European canals, although in some cases the height of the ship needs to, and can, be modified.
It took François Zanella, a mine builder, 11 years to build the model, beginning in 1993. The model was built on land opposite his home in Morsbach, which he purchased specifically for the project. After construction was completed in June 2005, the model was transported to Sarreguemines to be launched and christened. François Zanella's fame in France stemmed from the show Thalassa on France 3, which followed his activities during the construction period. He died in 2015.
Chronology
1993 First blueprint.
1994 Construction starts.
June 23, 2005 – ship launch in
Sarreguemines and christening by navigator Maud Fontenoy.
External links
Le Républicain Lorrain special edition dated June 21, 2005
The web site of Cindy, one of François Zanella's daughters
Sarreguemines city official web site, describing the three-day travel of the Majesty of the Seas from Morsbach construction site to ship launching.
Notes
Model boats
Passenger ships of France
2005 works
Royal Caribbean International
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https://en.wikipedia.org/wiki/Friday%20Night%20Football%20%28AFL%29
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Friday Night Football is an Australian sports broadcast series is currently airing on the Seven Network.
History
Non-weekend night matches of Australian rules football first emerged in the late 1970s/early 1980s with the night series, a knock-out tournament featuring teams from across the country and run in parallel with the league seasons.
The first Victorian Football League matches on Friday nights were introduced in 1985. At this time, these games were irregularly scheduled, and all matches featured North Melbourne, but by 1987, Friday Night Football was played on a more regular basis, and other clubs began to host the games.
Friday night AFL is generally played in Melbourne, at either the Melbourne Cricket Ground or Docklands Stadium, but Sydney, Adelaide and Perth will generally host a few matches each year. It is less common for the games to be played in Sydney, Brisbane or the Gold Coast in order to avoid clashes with the National Rugby League, which is more popular in those cities. As it is the most lucrative broadcast timeslot of the weekend, matches between the better-performing clubs are scheduled on Friday night to ensure the games are of high quality. As recently as 2014, however, the Gold Coast Suns have pushed to be featured on Friday nights in 2015, citing their improved form in 2014.
Seven's commentary team includes James Brayshaw, Brian Taylor and Hamish McLachlan, with smaller roles involving Wayne Carey, Cameron Ling, Tim Watson, Matthew Richardson, Leigh Matthews and Luke Darcy.
Broadcast history
The Seven Network, which broadcast football for around 40 years before losing the rights after the 2001 season, was the first Australian network to broadcast Friday Night Football.
Between 2002–2006, the Nine Network had the rights to the Friday night broadcast; as the network also had the rights to the NRL, during those years in Melbourne, Adelaide and Perth, where by the AFL match would be broadcast first live at 8:30pm, followed by Nightline (o
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https://en.wikipedia.org/wiki/Bayko
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Bayko was a British building model construction toy invented by Charles Plimpton, an early plastics engineer and entrepreneur in Liverpool. First marketed in Britain it was soon exported throughout the British Commonwealth and became a worldwide brand between 1934 and 1967. The name derived from Bakelite, one of the world's first commercial plastics that was originally used to manufacture many of the parts. Bayko was one of the world's earliest plastic toys to be marketed.
Bayko system
Bayko was primarily intended for the construction of model buildings. The rectangular Bakelite bases had a square grid of holes, spaced at 3/8 inch centres, into which thin metal rods, 75 thou [1.905 mm] in diameter, of various lengths, could be placed vertically. In order to make larger models, two or more bases could be joined together by means of metal links secured by screws through holes in the bases. Bakelite bricks, windows and other parts could then be slotted between pairs of rods in order to create the walls of the building. Other commonly used parts included floors (thin sheets of resin bonded paper with the same square pattern grid of holes as bases), and roofs of various types. There were also a large number of other more specialised parts. In the original sets bases were large, and coloured brown; walls were brown/maroon and cream; roofs were deep maroon; and windows were a very dark green, but by 1937 the 'true' colours of red or white walls, green windows and red roofs were established, though bases were still large and brown.
A period of radical change was heralded in 1938 with the introduction of the [now] much sought after 20s series, through which a number of new parts were introduced. Then, in 1939, the 'New Series' retooling programme added to the range of new parts and changed the bases to the more familiar, smaller version, initially in a mottled green. Post war the standard colours were red and white walls, red roofs, green windows and green bases,
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https://en.wikipedia.org/wiki/Ribonuclease%20III
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Ribonuclease III (RNase III or RNase C)(BRENDA 3.1.26.3) is a type of ribonuclease that recognizes dsRNA and cleaves it at specific targeted locations to transform them into mature RNAs. These enzymes are a group of endoribonucleases that are characterized by their ribonuclease domain, which is labelled the RNase III domain. They are ubiquitous compounds in the cell and play a major role in pathways such as RNA precursor synthesis, RNA Silencing, and the pnp autoregulatory mechanism.
Types of RNase III
The RNase III superfamily is divided into four known classes: 1, 2, 3, and 4. Each class is defined by its domain structure.
Class 1 RNase III
Class 1 RNase III enzymes have a homodimeric structure whose function is to cleave dsRNA into multiple subunits. It is a Mg2+-dependent endonuclease and is largely found in bacteria and bacteriophage. Class 1 RNase III have been found in Glomeromycotan fungi, which was suspected to be the result of horizontal gene transfer from cyanobacteria. Among the RNases III in the class are the rnc from E. coli. Typically, class I enzymes possess a single RNase III domain (RIIID) followed by a dsRNA-binding domain (). They process precursors to ribosomal RNA (rRNA), small nuclear RNA (snRNA) and small nucleolar RNA (snoRNA). The basic dsRNA cleavage function of Class 1 RNase III is retained in most of the organisms in which it is present. However, in a number of species the function has changed and taken on different or additional biological roles.
Rnc (UniProtKB P0A7Y0) - E.Coli - this RNase III is involved in the processing of viral transcripts and some mRNAs through the cleavage of multiple areas on the dsRNA. This cleavage can be influenced by ribosomal protein presence.
The variances of Class 1 RNase III, called Mini-III, are homodimeric enzymes and consist solely of the RNase III domains.
Class 2 RNase III
Class II is defined by the presence of an N-terminal domain (NTD), a RIIID, and a . Class II is found in some fungi spec
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https://en.wikipedia.org/wiki/Window%20of%20opportunity
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A window of opportunity, also called a margin of opportunity or critical window, is a period of time during which some action can be taken that will achieve a desired outcome. Once this period is over, or the "window is closed", the specified outcome is no longer possible.
Examples
Windows of opportunity include:
Biology and medicine
The critical period in neurological development, during which neuroplasticity is greatest and key functions, such as imprinting and language, are acquired which may be impossible to acquire at a later stage
The golden hour or golden time, used in emergency medicine to describe the period following traumatic injury in which life-saving treatment is most likely to be successful
Economics
Market opportunities, in which one may be positioned to take advantage of a gap in a particular market, the timing of which may depend on the activities of customers, competitors, and other market context factors
Limited time offer, a critical window for making purchases that is artificially imposed (or even falsely implied) as a marketing tactic to encourage consumer action
Other examples
Planting and harvesting seasons, in agriculture, which are generally timed to maximize crop yields
Space launch and maneuver windows, which are determined by orbital dynamics and mission goals and constrained by fuel/delta-v budgets
The theorized tipping point in climatology, after which the Earth's climate is predicted to shift to a new stable equilibrium
Various transient astronomical events, which present limited (and often unpredictable) windows for observation
Characteristics
Timing
The timing and length of a critical window may be well known and predictable (as in planetary transits) or more poorly understood (in the case of medical emergencies or climate change). In some cases, there may be multiple windows during which a goal can be achieved, as in the case of space launch windows.
In situations with very brief or unpredictable windows of opportunity, au
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https://en.wikipedia.org/wiki/Quantum%20annealing
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Quantum annealing (QA) is an optimization process for finding the global minimum of a given objective function over a given set of candidate solutions (candidate states), by a process using quantum fluctuations. Quantum annealing is used mainly for problems where the search space is discrete (combinatorial optimization problems) with many local minima; such as finding the ground state of a spin glass or the traveling salesman problem. The term "quantum annealing" was first proposed in 1988 by B. Apolloni, N. Cesa Bianchi and D. De Falco as a quantum-inspired classical algorithm. It was formulated in its present form by T. Kadowaki and H. Nishimori (ja) in 1998 though an imaginary-time variant without quantum coherence had been discussed by A. B. Finnila, M. A. Gomez, C. Sebenik and J. D. Doll in 1994.
Quantum annealing starts from a quantum-mechanical superposition of all possible states (candidate states) with equal weights. Then the system evolves following the time-dependent Schrödinger equation, a natural quantum-mechanical evolution of physical systems. The amplitudes of all candidate states keep changing, realizing a quantum parallelism, according to the time-dependent strength of the transverse field, which causes quantum tunneling between states or essentially tunneling through peaks. If the rate of change of the transverse field is slow enough, the system stays close to the ground state of the instantaneous Hamiltonian (also see adiabatic quantum computation). If the rate of change of the transverse field is accelerated, the system may leave the ground state temporarily but produce a higher likelihood of concluding in the ground state of the final problem Hamiltonian, i.e., diabatic quantum computation. The transverse field is finally switched off, and the system is expected to have reached the ground state of the classical Ising model that corresponds to the solution to the original optimization problem. An experimental demonstration of the success of qua
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https://en.wikipedia.org/wiki/Human%20Genome%20Project
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The Human Genome Project (HGP) was an international scientific research project with the goal of determining the base pairs that make up human DNA, and of identifying, mapping and sequencing all of the genes of the human genome from both a physical and a functional standpoint. It started in 1990 and was completed in 2003. It remains the world's largest collaborative biological project. Planning for the project started after it was adopted in 1984 by the US government, and it officially launched in 1990. It was declared complete on April 14, 2003, and included about 92% of the genome. Level "complete genome" was achieved in May 2021, with a remaining only 0.3% bases covered by potential issues. The final gapless assembly was finished in January 2022.
Funding came from the United States government through the National Institutes of Health (NIH) as well as numerous other groups from around the world. A parallel project was conducted outside the government by the Celera Corporation, or Celera Genomics, which was formally launched in 1998. Most of the government-sponsored sequencing was performed in twenty universities and research centres in the United States, the United Kingdom, Japan, France, Germany, and China, working in the International Human Genome Sequencing Consortium (IHGSC).
The Human Genome Project originally aimed to map the complete set of nucleotides contained in a human haploid reference genome, of which there are more than three billion. The "genome" of any given individual is unique; mapping the "human genome" involved sequencing samples collected from a small number of individuals and then assembling the sequenced fragments to get a complete sequence for each of 24 human chromosomes (22 autosomes and 2 sex chromosomes). Therefore, the finished human genome is a mosaic, not representing any one individual. Much of the project's utility comes from the fact that the vast majority of the human genome is the same in all humans.
History
The Human G
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https://en.wikipedia.org/wiki/Charge%20%28physics%29
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In physics, a charge is any of many different quantities, such as the electric charge in electromagnetism or the color charge in quantum chromodynamics. Charges correspond to the time-invariant generators of a symmetry group, and specifically, to the generators that commute with the Hamiltonian. Charges are often denoted by , and so the invariance of the charge corresponds to the vanishing commutator , where is the Hamiltonian. Thus, charges are associated with conserved quantum numbers; these are the eigenvalues of the generator .
Abstract definition
Abstractly, a charge is any generator of a continuous symmetry of the physical system under study. When a physical system has a symmetry of some sort, Noether's theorem implies the existence of a conserved current. The thing that "flows" in the current is the "charge", the charge is the generator of the (local) symmetry group. This charge is sometimes called the Noether charge.
Thus, for example, the electric charge is the generator of the U(1) symmetry of electromagnetism. The conserved current is the electric current.
In the case of local, dynamical symmetries, associated with every charge is a gauge field; when quantized, the gauge field becomes a gauge boson. The charges of the theory "radiate" the gauge field. Thus, for example, the gauge field of electromagnetism is the electromagnetic field; and the gauge boson is the photon.
The word "charge" is often used as a synonym for both the generator of a symmetry, and the conserved quantum number (eigenvalue) of the generator. Thus, letting the upper-case letter Q refer to the generator, one has that the generator commutes with the Hamiltonian [Q, H] = 0. Commutation implies that the eigenvalues (lower-case) q are time-invariant: = 0.
So, for example, when the symmetry group is a Lie group, then the charge operators correspond to the simple roots of the root system of the Lie algebra; the discreteness of the root system accounting for the quantization of the ch
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https://en.wikipedia.org/wiki/Nomen%20oblitum
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In zoological nomenclature, a nomen oblitum (plural: nomina oblita; Latin for "forgotten name") is a disused scientific name which has been declared to be obsolete (figuratively 'forgotten') in favour of another 'protected' name.
In its present meaning, the nomen oblitum came into being with the fourth, 1999, edition of the International Code of Zoological Nomenclature. After 1 January 2000, a scientific name may be formally declared to be a nomen oblitum when it has been shown not to have been used as a valid name within the scientific community since 1899, and when it is either a senior synonym (there is also a more recent name which applies to the same taxon, and which is in common use) or a homonym (it is spelled the same as another name, which is in common use), and when the preferred junior synonym or homonym has been shown to be in wide use in 50 or more publications in the past few decades. Once a name has formally been declared to be a nomen oblitum, the now obsolete name is to be 'forgotten'. By the same act, the next available name must be declared to be protected under the title nomen protectum. Thereafter it takes precedence.
An example is the case of the scientific name for the leopard shark. Despite the name Mustelus felis being the senior synonym, an error in recording the dates of publication resulted in the widespread use of Triakis semifasciata as the leopard shark's scientific name. After this long-standing error was discovered, T. semifasciata was made the valid name (as a nomen protectum) and Mustelus felis was declared invalid (as a nomen oblitum).
Use in taxonomy
The designation nomen oblitum has been used relatively frequently to keep the priority of old, sometimes disused names, and, controversially, often without establishing that a name actually meets the criteria for the designation. Some taxonomists have regarded the failure to properly establish the nomen oblitum designation as a way to avoid doing taxonomic research or to retain a
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https://en.wikipedia.org/wiki/Reeler
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A reeler is a mouse mutant, so named because of its characteristic "reeling" gait. This is caused by the profound underdevelopment of the mouse's cerebellum, a segment of the brain responsible for locomotion. The mutation is autosomal and recessive, and prevents the typical cerebellar folia from forming.
Cortical neurons are generated normally but are abnormally placed, resulting in disorganization of cortical laminar layers in the central nervous system. The reason is the lack of reelin, an extracellular matrix glycoprotein, which, during the corticogenesis, is secreted mainly by the Cajal–Retzius cells.
In the reeler neocortex, cortical plate neurons are aligned in a practically inverted fashion ("outside-in"). In the ventricular zone of the cortex fewer neurons have been found to have radial glial processes. In the dentate gyrus of hippocampus, no characteristic radial glial scaffold is formed and no compact granule cell layer is established. Therefore, the reeler mouse presents a good model in which to investigate the mechanisms of establishment of the precise neuronal network during development.
Types of reelers
There are two types of the reeler mutation:
Albany2 mutation (Reln(rl-Alb2)
Orleans mutation (Reln-rl-orl, or rl-orl), in which reelin lacks a C-terminal region and a part of the eighth reelin repeat. This hampers the secretion of the protein from the cell.
In order to unravel the reelin signaling chain, attempts are made to cut the signal downstream of reelin, leaving reelin expression intact but creating the reeler phenotype, sometimes a partial phenotype, thus confirming the role of downstream molecules. The examples include:
Double knockout of VLDLR and ApoER2 receptors;
Double knockout of Src and Fyn kinases.
Cre-loxP recombination mice model that lacks Crk and CrkL in most neurons. Was used to show that Crk/CrkL lie downstream of DAB1] in the reelin signaling pathway.
Scrambler mouse
Key pathological findings in the reeler brain structu
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https://en.wikipedia.org/wiki/List%20of%20centroids
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The following is a list of centroids of various two-dimensional and three-dimensional objects. The centroid of an object in -dimensional space is the intersection of all hyperplanes that divide into two parts of equal moment about the hyperplane. Informally, it is the "average" of all points of . For an object of uniform composition, the centroid of a body is also its center of mass. In the case of two-dimensional objects shown below, the hyperplanes are simply lines.
2-D Centroids
For each two-dimensional shape below, the area and the centroid coordinates are given:
Where the centroid coordinates are marked as zero, the coordinates are at the origin, and the equations to get those points are the lengths of the included axes divided by two, in order to reach the center which in these cases are the origin and thus zero.
3-D Centroids
For each three-dimensional body below, the volume and the centroid coordinates are given:
See also
List of moments of inertia
List of second moments of area
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https://en.wikipedia.org/wiki/Centralized%20computing
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Centralized computing is computing done at a central location, using terminals that are attached to a central computer. The computer itself may control all the peripherals directly (if they are physically connected to the central computer), or they may be attached via a terminal server. Alternatively, if the terminals have the capability, they may be able to connect to the central computer over the network. The terminals may be text terminals or thin clients, for example.
It offers greater security over decentralized systems because all of the processing is controlled in a central location. In addition, if one terminal breaks down, the user can simply go to another terminal and log in again, and all of their files will still be accessible. Depending on the system, they may even be able to resume their session from the point they were at before, as if nothing had happened.
This type of arrangement does have some disadvantages. The central computer performs the computing functions and controls the remote terminals. This type of system relies totally on the central computer. Should the central computer crash, the entire system will "go down" (i.e. will be unavailable).
Another disadvantage is that central computing relies heavily on the quality of administration and resources provided to its users. Should the central computer be inadequately supported by any means (e.g. size of home directories, problems regarding administration), then your usage will suffer greatly. The reverse situation, however, (i.e., a system supported better than your needs) is one of the key advantages to centralized computing.
History
The very first computers did not have separate terminals as such; their primitive input/output devices were built in. However, soon it was found to be extremely useful for multiple people to be able to use a computer at the same time, for reasons of cost – early computers were very expensive, both to produce and maintain, and occupied large amounts of floo
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https://en.wikipedia.org/wiki/Gauged%20supergravity
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Gauged supergravity is a supergravity theory in which some R-symmetry is gauged such that the gravitinos (superpartners of the graviton) are charged with respect to the gauge fields. Consistency of the supersymmetry transformation often requires
the presence of the potential for the scalar fields of the theory, or the cosmological constant if the theory
contains no scalar degree of freedom. The gauged supergravity often has the anti-de Sitter space as a supersymmetric vacuum.
Notable exception is a six-dimensional N=(1,0) gauged supergravity.
"Gauged supergravity" in this sense should be contrasted with Yang–Mills–Einstein supergravity in which some other would-be global symmetries of the theory are gauged and fields other than the gravitinos are charged with respect to the gauge fields.
See also
Velo–Zwanziger problem
Supersymmetry
Theory of relativity
Quantum gravity
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https://en.wikipedia.org/wiki/Cell%20damage
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Cell damage (also known as cell injury) is a variety of changes of stress that a cell suffers due to external as well as internal environmental changes. Amongst other causes, this can be due to physical, chemical, infectious, biological, nutritional or immunological factors. Cell damage can be reversible or irreversible. Depending on the extent of injury, the cellular response may be adaptive and where possible, homeostasis is restored. Cell death occurs when the severity of the injury exceeds the cell's ability to repair itself. Cell death is relative to both the length of exposure to a harmful stimulus and the severity of the damage caused. Cell death may occur by necrosis or apoptosis.
Causes
Physical agents such as heat or radiation can damage a cell by literally cooking or coagulating their contents.
Impaired nutrient supply, such as lack of oxygen or glucose, or impaired production of adenosine triphosphate (ATP) may deprive the cell of essential materials needed to survive.
Metabolic: Hypoxia and Ischemia
Chemical Agents
Microbial Agents: Virus & Bacteria
Immunologic Agents: Allergy and autoimmune diseases such as Parkinson's and Alzheimer's disease.
Genetic factors: Such as Down's syndrome and sickle cell anemia
Targets
The most notable components of the cell that are targets of cell damage are the DNA and the cell membrane.
DNA damage: In human cells, both normal metabolic activities and environmental factors such as ultraviolet light and other radiations can cause DNA damage, resulting in as many as one million individual molecular lesions per cell per day.
Membrane damage: Damage to the cell membrane disturbs the state of cell electrolytes, e.g. calcium, which when constantly increased, induces apoptosis.
Mitochondrial damage: May occur due to ATP decrease or change in mitochondrial permeability.
Ribosome damage: Damage to ribosomal and cellular proteins such as protein misfolding, leading to apoptotic enzyme activation.
Types of damage
Some cell da
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https://en.wikipedia.org/wiki/Windows%20System%20Assessment%20Tool
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The Windows System Assessment Tool (WinSAT) is a module of Microsoft Windows Vista, Windows 7, Windows 8, Windows 10 and Windows 11 that is available in the Control Panel under Performance Information and Tools (except in Windows 8.1, Windows 10 & Windows 11). It measures various performance characteristics and capabilities of the hardware it is running on and reports them as a Windows Experience Index (WEI) score. The WEI includes five subscores: processor, memory, 2D graphics, 3D graphics, and disk; the basescore is equal to the lowest of the subscores and is not an average of the subscores. WinSAT reports WEI scores on a scale from 1.0 to 5.9 for Windows Vista, 7.9 for Windows 7, and 9.9 for Windows 8, Windows 10 and Windows 11.
The WEI enables users to match their computer hardware performance with the performance requirements of software. For example, the Aero graphical user interface will not automatically be enabled unless the system has a WEI score of 3 or higher.
The WEI can also be used to show which part of a system would be expected to provide the greatest increase in performance when upgraded. For example, a computer with the lowest subscore being its memory, would benefit more from a RAM upgrade than adding a faster hard drive (or any other component).
Detailed raw performance information, like actual disk bandwidth, can be obtained by invoking winsat from the command line. This also allows only specific tests to be re-run. Obtaining the WEI score from the command line is done invoking winsat formal, which also updates the value stored in %systemroot%\Performance\WinSAT\DataStore. (The XML files stored there can be easily hacked to report fake performance values.) The WEI is also available to applications through an API, so they can configure themselves as a function of hardware performance, taking advantage of its capabilities without becoming unacceptably slow.
The Windows Experience Index score is not displayed in Windows 8.1 and onwards because
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https://en.wikipedia.org/wiki/Lees%20%28fermentation%29
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Lees are deposits of dead yeast or residual yeast and other particles that precipitate, or are carried by the action of "fining", to the bottom of a vat of wine after fermentation and aging. The same while brewing beer at a brewery is known as trub – the same from secondary fermentation of wine and beer are the lees or equally, as to beer only, dregs. This material is the source for most commercial tartaric acid, which is used in cooking and in organic chemistry.
Normally, the wine is transferred to another container (racking), leaving this sediment behind. Some wines (notably Chardonnay, Champagne, and Muscadet) are sometimes aged for a time on the lees (a process known as sur lie), leading to a distinctive yeasty aroma and taste. The lees may be stirred () for uptake of their flavour.
The lees are an important component in the making of ripasso, where the leftover lees from Amarone are used to impart more flavour and colour to partially aged Valpolicella.
Fujian red wine chicken is made from rice wine lees.
Sur lie
Sur lie literally translates from French as 'on lees'. Sur lie wines are bottled directly from the lees without racking (a process for filtering the wine). In the case of great Chardonnay, such as Montrachet, this adds a toasty, nutty "hazelnut" quality and additional depth and complexity. Chemically, this can alter the oak flavour molecules, increasing the integration, and making the oak seem less obtrusive to the palate. This is desirable because oak tannins are polyphenolic acids, and can be harsh. This process can also give an added freshness and creaminess to the wine, and improve color and clarity. Muscadet is made in this fashion. The effect of the lees during bottle fermentation for at least 18 months on Champagne is considerable. The "bready" toasty notes associated with some of the greatest sparkling wines made are the result of sur lie aging.
Other uses
Beer on an element of lees (residual sediment) is also sold, such as many
Trappist
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https://en.wikipedia.org/wiki/Privacy%20law
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Privacy law is the body of law that deals with the regulating, storing, and using of personally identifiable information, personal healthcare information, and financial information of individuals, which can be collected by governments, public or private organisations, or other individuals. It also applies in the commercial sector to things like trade secrets and the liability that directors, officers, and employees have when handing sensitive information.
Privacy laws are considered within the context of an individual's privacy rights or within reasonable expectation of privacy. The Universal Declaration of Human Rights states that everyone has the right to privacy. The interpretation of these rights varies by country and is not always universal.
Classification of privacy laws
Privacy laws can be broadly classified into:
General privacy laws that have an overall bearing on the personal information of individuals and affect the policies that govern many different areas of information.
Trespass
Negligence
Fiduciary
International legal standards on privacy
Asia-Pacific Economic Cooperation (APEC)
APEC created a voluntary Privacy Framework that was adopted by all 21 member economies in 2004 in an attempt to improve general information privacy and the cross-border transfer of information. The Framework consists of nine Privacy Principles that act as minimum standards for privacy protection: Preventing harm, Notice, Collection limitation, Use of personal information, Choice, Integrity of personal information, Security safeguards, Access and correction, and Accountability.
In 2011, APEC implemented the APEC Cross Border Privacy Rules System with the goal of balancing "the flow of information and data across borders ... essential to trust and confidence in the online marketplace." The four agreed-upon rules of the System are based upon the APEC Privacy Framework and include self-assessment, compliance review, recognition/acceptance, and dispute resolution and enforc
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https://en.wikipedia.org/wiki/Dalfopristin
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Dalfopristin is a semi-synthetic streptogramin antibiotic analogue of ostreogyrcin A (virginiamycin M, pristinamycin IIA, streptogramin A). The combination quinupristin/dalfopristin (marketed under the trade name Synercid) was brought to the market by Rhone-Poulenc Rorer Pharmaceuticals in 1999. Synercid (weight-to-weight ratio of 30% quinupristin to 70% dalfopristin) is used to treat infections by staphylococci and by vancomycin-resistant Enterococcus faecium.
Synthesis
Through the addition of diethylaminoethylthiol to the 2-pyrroline group and oxidation of the sulfate of ostreogrycin A, a structurally more hydrophobic compound is formed. This hydrophobic compound contains a readily ionizable group that is available for salt formation.
Large Scale Preparation
Dalfopristin is synthesized from pristinamycine IIa through achieving a stereoselective Michael-type addition of 2-diethylaminoethanethiol on the conjugated double bond of the dehydroproline ring
. The first method found was using sodium periodate associated with ruthenium dioxide to directly oxidize the sulfur derivative into a sulfone. However, using hydrogen peroxide with sodium tungstate in a 2-phase medium produces an improved yield, and is therefore the method of choice for large scale production.
The production of the dalfopristin portion of quinupristin/dalfopristin is achieved through purifying cocrystallization of the quinupristin and dalfopristin from acetone solutions.
Physical Characteristics (as mesylate salt)
Antimicrobial activity
Alone, both dalfopristin and quinupristin have modest in vitro bacteriostatic activity. However, 8-16 times higher in vitro bactericidal activity is seen against many gram-positive bacteria when the two streptogramins are combined
. While quinupristin/dalfopristin is effective against staphylococci and vancomycin-resistant Enterococcus faecium, in vitro studies have not demonstrated bactericidal activity against all strains and species of common gram-positive
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https://en.wikipedia.org/wiki/Overlapping%20generations
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In population genetics overlapping generations refers to mating systems where more than one breeding generation is present at any one time. In systems where this is not the case there are non-overlapping generations (or discrete generations) in which every breeding generation lasts just one breeding season. If the adults reproduce over multiple breeding seasons the species is considered to have overlapping generations. Examples of species which have overlapping generations are many mammals, including humans, and many invertebrates in seasonal environments. Examples of species which consist of non-overlapping generations are annual plants and several insect species.
Non-overlapping generations is one of the characteristics that needs to be met in the Hardy–Weinberg model for evolution to occur. This is a very restrictive and unrealistic assumption, but one that is difficult to dispose of.
Overlapping versus non-overlapping generations
In population genetics models, such as the Hardy–Weinberg model, it is assumed that species have no overlapping generations. In nature, however, many species do have overlapping generations. The overlapping generations are considered the norm rather than the exception.
Overlapping generations are found in species that live for many years, and reproduce many times. Many birds, for instance, have new nests every (couple of) year(s). Therefore, the offspring will, after they have matured, also have their own nests of offspring while the parent generation could be breeding again as well. An advantage of overlapping generations can be found in the different experience levels of generations in a population. The younger age group will be able to acquire social information from the older and more experienced age groups. Overlapping generations can, similarly, promote altruistic behaviour.
Non-overlapping generations are found in species in which the adult generation dies after one breeding season. If a species for instance can only survive
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https://en.wikipedia.org/wiki/Mwave
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Mwave was a technology developed by IBM allowing for the combination of telephony and sound card features on a single adapter card. The technology centers around the Mwave digital signal processor (DSP). The technology was used for a time to provide a combination modem and sound card for IBM's Aptiva line and some ThinkPad laptops, in addition to uses on specialized Mwave cards that handled voice recognition or ISDN networking connectivity. Similar adapter cards by third-party vendors using Mwave technology were also sold. However, plagued by consumer complaints about buggy Mwave software and hardware, IBM eventually turned to other audio and telephony solutions for its consumer products.
History
Malcolm Ware, a former developer on Mwave, dates the technology back to its development in an IBM research lab in Zurich, Switzerland in 1979. The first prototype was tested in an IBM PC in 1981. After being utilized in some other adapter cards, Mwave was given its official name and used in IBM's WindSurfer ISA/MCA card. IBM manufactured Mwave hardware for both Microsoft Windows and its own OS/2. Another revision of the technology was used in IBM's newly renamed Aptiva line. Gary Harper developed some automated test software, loosely based on the movie War Games, to test how well the Mwave modem could connect to modems used by various bulletin board systems.
One of the revisions of the Mwave card was the Mwave Dolphin. The card was an ISA legacy card that did not support plug and play and natively supported Windows through its software. It featured a 28.8k/second fax/modem and a Sound Blaster-compatible audio solution. One of the card's most publicized features was its software upgradeability: a version of the Mwave software upgraded the modem function to 33.6k. In addition, the card was key in the support of some of the Aptiva's Rapid Resume features, including Wake-up On Ring. There were various consumer complaints with users reporting problems involving either the so
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https://en.wikipedia.org/wiki/MathChallengers
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MathChallengers is the former Mathcounts in British Columbia. It is open to all grade 8, 9, and 10 students from British Columbia. The major sponsors are the Association of Professional Engineers and Geoscientists of B.C. (APEGBC), the B.C. Association of Mathematics Teachers (BCAMT), BC Hydro, and IBM Canada.
Rules
The Competition consists of 4 stages. Stages 1 and 2 are individual competitions. Stage 3 is a Team competition. Stage 4 is a one-on-one competition between the top 10 individuals who participated in stages 1 and 2. Math Challengers competitions may consist of the following rounds:
Stage 1: "Blitz"
Stage 1 consists of one session on a variety of mathematical subjects. Participants will be allowed to work for 40 minutes on 26 questions written on four pages (each correct answer will count as one point). Thus, the maximum number of points available in this stage is: 26.
Stage 2: "Bulls-Eye"
Stage 2 consists of three sessions on a certain mathematical subject. For each of the sessions, participants will be given 12 minutes to work on the 4 questions on that subject. The total number of questions in Stage 1 is 12 and each correct answer will count as two points. Thus, the maximum number of points available in this stage is: 24.
Stage 3: "Co-Op"
Stage 3 is a Team competition and it consists of three sessions on a variety of mathematical subjects. Participants will be allowed to work for 36 minutes on 15 questions written on one page (each correct answer will count as two points). Thus, the maximum number of points available in this stage is 30. Scientific calculators are allowed for this stage of the competition. Graphing calculators and programmable calculators are not allowed at all. Devices with wireless communication capabilities are absolutely not allowed.
Stage 4: "Face-Off"
Stage 4 is a one-to-one buzz-in verbal competition for the top scoring 10 individuals.
There will be a total of 9 match up rounds.
Participants should be provided with a
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https://en.wikipedia.org/wiki/Myco-heterotrophy
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Myco-heterotrophy (from Greek μύκης , "fungus", ἕτερος , "another", "different" and τροφή , "nutrition") is a symbiotic relationship between certain kinds of plants and fungi, in which the plant gets all or part of its food from parasitism upon fungi rather than from photosynthesis. A myco-heterotroph is the parasitic plant partner in this relationship. Myco-heterotrophy is considered a kind of cheating relationship and myco-heterotrophs are sometimes informally referred to as "mycorrhizal cheaters". This relationship is sometimes referred to as mycotrophy, though this term is also used for plants that engage in mutualistic mycorrhizal relationships.
Relationship between myco-heterotrophs and host fungi
Full (or obligate) myco-heterotrophy exists when a non-photosynthetic plant (a plant largely lacking in chlorophyll or otherwise lacking a functional photosystem) gets all of its food from the fungi that it parasitizes. Partial (or facultative) myco-heterotrophy exists when a plant is capable of photosynthesis, but parasitizes fungi as a supplementary food supply. There are also plants, such as some orchid species, that are non-photosynthetic and obligately myco-heterotrophic for part of their life cycle, and photosynthetic and facultatively myco-heterotrophic or non-myco-heterotrophic for the rest of their life cycle. Not all non-photosynthetic or "achlorophyllous" plants are myco-heterotrophic – some non-photosynthetic plants like dodder directly parasitize the vascular tissue of other plants. The partial or full loss of photosynthesis is reflected by extreme physical and functional reductions of plastid genomes in mycoheterophic plants, an ongoing evolutionary process.
In the past, non-photosynthetic plants were mistakenly thought to get food by breaking down organic matter in a manner similar to saprotrophic fungi. Such plants were therefore called "saprophytes". It is now known that these plants are not physiologically capable of directly breaking down organ
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https://en.wikipedia.org/wiki/Grundy%20number
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In graph theory, the Grundy number or Grundy chromatic number of an undirected graph is the maximum number of colors that can be used by a greedy coloring strategy that considers the vertices of the graph in sequence and assigns each vertex its first available color, using a vertex ordering chosen to use as many colors as possible. Grundy numbers are named after P. M. Grundy, who studied an analogous concept for directed graphs in 1939. The undirected version was introduced by .
Example
For example, for a path graph with four vertices, the chromatic number is two but the Grundy number is three: if the two endpoints of the path are colored first, the greedy coloring algorithm will use three colors for the whole graph.
Atoms
defines a sequence of graphs called -atoms, with the property that a graph has Grundy number at least if and only if it contains a -atom.
Each -atom is formed from an independent set and a -atom, by adding one edge from each vertex of the -atom to a vertex of the independent set, in such a way that each member of the independent set has at least one edge incident to it.
A Grundy coloring of a -atom can be obtained by coloring the independent set first with the smallest-numbered color, and then coloring the remaining -atom with an additional colors.
For instance, the only 1-atom is a single vertex, and the only 2-atom is a single edge, but there are two possible 3-atoms: a triangle and a four-vertex path.
In sparse graphs
For a graph with vertices and degeneracy , the Grundy number is . In particular, for graphs of bounded degeneracy (such as planar graphs) or graphs for which the chromatic number and degeneracy are bounded within constant factors of each other (such as chordal graphs) the Grundy number and chromatic number are within a logarithmic factor of each other. For interval graphs, the chromatic number and Grundy number are within a factor of 8 of each other.
Computational complexity
Testing whether the Grundy number of a given gra
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https://en.wikipedia.org/wiki/George%20Sellios
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George Sellios was the owner of Fine Scale Miniatures (FSM), a business dedicated to producing detailed model kits of structures for model railroad enthusiasts. He is also an accomplished modeler and is well-known in the hobby for his layout, the Franklin & South Manchester Railroad which attracts visitors from around the world.
Fine Scale Miniatures
FSM produced craftsman structure kits from 1967 through 2016 from its location in Peabody, Massachusetts, along with guides to the construction of detailed model railroads.
Franklin & South Manchester
The F&SM uses the same initials as Sellios' company and is co-located in the former FSM company office. It is a stylized model railroad set in 1935 in a fictional area of New England during the Great Depression, characterized by cluttered scenery, colorful billboards and signs, simulated dilapidation, weedy sidewalks, heavy weathering and artistic license.
Active in the hobby since he was 13, Sellios' first influence in the hobby was John Allen who took a novel, whimsical approach to model trains. Allen's influence can be seen in Sellios' work, which favors fantasy over the prototypical. In at least two cases, early Sellios kits are copies of John Allen designs.
Sellios began construction of the F&SM in April 1985. He dedicated approximately three months per year to the endeavor, with the remaining nine dedicated to design and production for his business selling model structure kits. Sellios' F&SM is a large diorama occupying a space measuring approximately . Sellios' model railroad has become one of the most recognized over the years, with several feature articles in Model Railroader and an episode of Tracks Ahead. Sellios has a large following of model train enthusiasts in the United States, where his exaggerated, caricature style is emulated by hobbyists and cottage industry "craftsman kit" makers.
There are four commercial videos dedicated to the F&SM, produced by the Allen Keller Great Model Railroads series (e
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https://en.wikipedia.org/wiki/Oligolecty
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The term oligolecty is used in pollination ecology to refer to bees that exhibit a narrow, specialized preference for pollen sources, typically to a single family or genus of flowering plants. The preference may occasionally extend broadly to multiple genera within a single plant family, or be as narrow as a single plant species. When the choice is very narrow, the term monolecty is sometimes used, originally meaning a single plant species but recently broadened to include examples where the host plants are related members of a single genus. The opposite term is polylectic and refers to species that collect pollen from a wide range of species. The most familiar example of a polylectic species is the domestic honey bee.
Oligolectic pollinators are often called oligoleges or simply specialist pollinators, and this behavior is especially common in the bee families Andrenidae and Halictidae, though there are thousands of species in hundreds of genera, in essentially all known bee families; in certain areas of the world, such as deserts, oligoleges may represent half or more of all the resident bee species. Attempts have been made to determine whether a narrow host preference is due to an inability of the bee larvae to digest and develop on a variety of pollen types, or a limitation of the adult bee's learning and perception (i.e., they simply do not recognize other flowers as potential food sources), and most of the available evidence suggests the latter. However, a few plants whose pollen contains toxic substances (e.g., Toxicoscordion and related genera in the Melanthieae) are visited by oligolectic bees, and these may fall into the former category. The evidence from large-scale phylogenetic analyses of bee evolution suggests that, for most groups of bees, oligolecty is the ancestral condition and polylectic lineages arose from among those ancestral specialists.
There are some cases where oligoleges collect their host plant's pollen as larval food but, for various r
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https://en.wikipedia.org/wiki/Cytidine%20triphosphate
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Cytidine triphosphate (CTP) is a pyrimidine nucleoside triphosphate. CTP, much like ATP, consists of a ribose sugar, and three phosphate groups. The major difference between the two molecules is the base used, which in CTP is cytosine.
CTP is a substrate in the synthesis of RNA.
CTP is a high-energy molecule similar to ATP, but its role as an energy coupler is limited to a much smaller subset of metabolic reactions.
CTP is a coenzyme in metabolic reactions like the synthesis of glycerophospholipids, where it is used for activation and transfer of diacylglycerol and lipid head groups, and glycosylation of proteins.
CTP acts as an inhibitor of the enzyme aspartate carbamoyltransferase, which is used in pyrimidine biosynthesis.
See also
CTP synthase
Cytidine
Cytosine
Pyrimidine biosynthesis
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https://en.wikipedia.org/wiki/Mycotroph
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A mycotroph is a plant that gets all or part of its carbon, water, or nutrient supply through symbiotic association with fungi. The term can refer to plants that engage in either of two distinct symbioses with fungi:
Many mycotrophs have a mutualistic association with fungi in any of several forms of mycorrhiza. The majority of plant species are mycotrophic in this sense. Examples include Burmanniaceae.
Some mycotrophs are parasitic upon fungi in an association known as myco-heterotrophy.
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https://en.wikipedia.org/wiki/D-STAR
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D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol specification for amateur radio. The system was developed in the late 1990s by the Japan Amateur Radio League and uses minimum-shift keying in its packet-based standard. There are other digital modes that have been adapted for use by amateurs, but D-STAR was the first that was designed specifically for amateur radio.
Several advantages of using digital voice modes are that it uses less bandwidth than older analog voice modes such as amplitude modulation and frequency modulation. The quality of the data received is also better than an analog signal at the same signal strength, as long as the signal is above a minimum threshold and as long as there is no multipath propagation.
D-STAR compatible radios are available for HF, VHF, UHF, and microwave amateur radio bands. In addition to the over-the-air protocol, D-STAR also provides specifications for network connectivity, enabling D-STAR radios to be connected to the Internet or other networks, allowing streams of voice or packet data to be routed via amateur radio.
D-STAR compatible radios are manufactured by Icom, Kenwood, and FlexRadio Systems.
History
In 1998 an investigation into finding a new way of bringing digital technology to amateur radio was started. The process was funded by a ministry of the Japanese government, then called the Ministry of Posts and Telecommunications, and administered by the Japan Amateur Radio League. In 2001, D-STAR was published as the result of the research.
In September 2003 Icom named Matt Yellen, KB7TSE (now K7DN), to lead its US D-STAR development program.
Starting in April 2004 Icom began releasing new "D-STAR optional" hardware. The first to be released commercially, was a 2-meter mobile unit designated IC-2200H. Icom followed up with 2 meter and 440 MHz handheld transceivers the next year. However, the yet to be released UT-118 add-on card was required for these radios to operate i
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https://en.wikipedia.org/wiki/Information%20Trust%20Institute
|
The Information Trust Institute (ITI) was founded in 2004 as an interdisciplinary unit designed to approach information security research from a systems perspective. It examines information security by looking at what makes machines, applications, and users trustworthy. Its mission is to create computer systems, software, and networks that society can depend on to be trustworthy, meaning secure, dependable (reliable and available), correct, safe, private, and survivable. ITI's stated goal is to create a new paradigm for designing trustworthy systems from the ground up and validating systems that are intended to be trustworthy.
Participants
ITI is an academic/industry partnership focusing on application areas such as electric power, financial systems, defense, and homeland security, among others. It brings together over 100 researchers representing numerous colleges and units at the University of Illinois at Urbana–Champaign.
Major centers within ITI
Boeing Trusted Software Center
CAESAR: the Center for Autonomous Engineering Systems and Robotics
the Center for Information Forensics
Center for Health Information Privacy and Security
the NSA Center for Information Assurance Education and Research
TCIPG: the Trustworthy Cyber Infrastructure for the Power Grid Center
Trusted ILLIAC
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https://en.wikipedia.org/wiki/Kinetic%20Monte%20Carlo
|
The kinetic Monte Carlo (KMC) method is a Monte Carlo method computer simulation intended to simulate the time evolution of some processes occurring in nature. Typically these are processes that occur with known transition rates among states. It is important to understand that these rates are inputs to the KMC algorithm, the method itself cannot predict them.
The KMC method is essentially the same as the dynamic Monte Carlo method and the Gillespie algorithm.
Algorithms
One possible classification of KMC algorithms is as rejection-KMC (rKMC) and rejection-free-KMC (rfKMC).
Rejection-free KMC
A rfKMC algorithm, often only called KMC, for simulating the time evolution of a system, where some processes can occur with known rates r, can be written for instance as follows:
Set the time .
Choose an initial state k.
Form the list of all possible transition rates in the system , from state k into a generic state i. States that do not communicate with k will have .
Calculate the cumulative function for . The total rate is .
Get a uniform random number .
Find the event to carry out i by finding the i for which (this can be achieved efficiently using binary search).
Carry out event i (update the current state ).
Get a new uniform random number .
Update the time with , where .
Return to step 3.
(Note: because the average value of is equal to unity, the same average time scale can be obtained by instead using in step 9. In this case, however, the delay associated with transition i will not be drawn from the Poisson distribution described by the rate , but will instead be the mean of that distribution.)
This algorithm is known in different sources variously as the residence-time algorithm or the n-fold way or the Bortz-Kalos-Lebowitz (BKL) algorithm. It is important to note that the timestep involved is a function of the probability that all events i, did not occur.
Rejection KMC
Rejection KMC has typically the advantage of an easier data handling, and
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https://en.wikipedia.org/wiki/Crustose
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Crustose is a habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. Crustose adheres very closely to the substrates at all points. Crustose is found on rocks and tree bark. Some species of marine algae of the Rhodophyta, in particular members of the order Corallinales, family Corallinaceae, subfamily Melobesioideae with cell walls containing calcium carbonate grow to great depths in the intertidal zone, forming crusts on various substrates. The substrate can be rocks throughout the intertidal zone, or, as in the case of the Corallinales, reef-building corals, and other living organisms including plants, such as mangroves and animals such as shelled molluscs. The coralline red algae are major members of coral reef communities, cementing the corals together with their crusts. Among the brown algae, the order Ralfsiales comprises two families of crustose algae.
Growth and habitat
Many lichens grow close to the surface of rocks, tree trunks, and other substrata, and are referred to as crustose lichens. Crustose organisms can be detrimental to engineered structures when found on buildings, coastal structures, and ships.
There are different types of Crustose lichens, including endolithic, endophloidic and leprose. Endolithic lichens are immersed in the outer layer of rocks with their bodies above the surface. Endophloidic ones are located in or on plant tissue. Leprose lichens consist of crusts without a layered structure.
Crustose lichens have learned to adapt to their environment, with the shells helping with adaptation to dry and drought resistant climates. Crustose lichens have been found in deserts, ice free parts of Antarctica, and in the Alpine and Arctic regions.
Characteristics
Crustose can come in a variety of colors such as yellow, orange, red, gray and green. These colors tend to be bright and vibrant.
Crustose is similar to other lichens because they share a similar interna
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https://en.wikipedia.org/wiki/Misha%20Verbitsky
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Misha Verbitsky (, born June 20, 1969, in Moscow) is a Russian mathematician. He works at the Instituto Nacional de Matemática Pura e Aplicada in Rio de Janeiro. He is primarily known to the general public as a controversial critic, political activist and independent music publisher.
Scientific activities
Verbitsky graduated from a Math class at the Moscow State School 57 in 1986, and has been active in mathematics since then. His principal area of interest in mathematics is differential geometry, especially geometry of hyperkähler manifolds and locally conformally Kähler manifolds. He proved an analogue of the global Torelli theorem for hyperkähler manifolds and the mirror conjecture in hyperkähler case. He also contributed to the theory of Hodge structures. His PhD thesis, titled Cohomology of compact Hyperkaehler Manifolds, was defended in 1995 at Harvard University under the supervision of David Kazhdan. He has held different positions, most prominently at the Independent University of Moscow (since 1996), the University of Glasgow (2002–2007), and the HSE Faculty of Mathematics (since 2010). He currently works at IMPA in Rio de Janeiro.
Lenin
Verbitsky's webzine :LENIN:, started around 1997, is one of the oldest Russian online projects and has been hugely influential in the shaping of Russian counter-culture. It was the first website in Russian to openly discuss topics considered taboo at the time, such as pornography and Right-wing extremism, and to create a milieu for the emerging counter-culture aesthetic. The site also contains the largest single collection of rare underground music from the ex-USSR and contemporary Russia.
Western counter-culture
While studying mathematics at Harvard University in the early 90s, Verbitsky was heavily influenced by Western counter-culture, especially Thelema and industrial music, and was the first to introduce these concepts to post-Soviet Russia via his webzine. At the same time, Verbitsky developed his political views
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https://en.wikipedia.org/wiki/Slipped%20strand%20mispairing
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Slipped strand mispairing (SSM, also known as replication slippage) is a mutation process which occurs during DNA replication. It involves denaturation and displacement of the DNA strands, resulting in mispairing of the complementary bases. Slipped strand mispairing is one explanation for the origin and evolution of repetitive DNA sequences.
It is a form of mutation that leads to either a trinucleotide or dinucleotide expansion, or sometimes contraction, during DNA replication. A slippage event normally occurs when a sequence of repetitive nucleotides (tandem repeats) are found at the site of replication. Tandem repeats are unstable regions of the genome where frequent insertions and deletions of nucleotides can take place, resulting in genome rearrangements. DNA polymerase, the main enzyme to catalyze the polymerization of free deoxyribonucleotides into a newly forming DNA strand, plays a significant role in the occurrence of this mutation. When DNA polymerase encounters a direct repeat, it can undergo a replication slippage.
Strand slippage may also occur during the DNA synthesis step of DNA repair processes. Within DNA trinucleotide repeat sequences, the repair of DNA damage by the processes of homologous recombination, non-homologous end joining, DNA mismatch repair or base excision repair may involve strand slippage mispairing leading to trinucleotide repeat expansion when the repair is completed.
Slipped strand mispairing has also been shown to function as a phase variation mechanism in certain bacteria.
Stages
Slippage occurs through five main stages:
In the first step, DNA polymerase encounters the direct repeat during the replication process.
The polymerase complex suspends replication and is temporarily released from the template strand.
The newly synthesized strand then detaches from the template strand and pairs with another direct repeat upstream.
DNA polymerase reassembles its position on the template strand and resumes normal replication,
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https://en.wikipedia.org/wiki/Systems%20for%20Nuclear%20Auxiliary%20Power
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The Systems Nuclear Auxiliary POWER (SNAP) program was a program of experimental radioisotope thermoelectric generators (RTGs) and space nuclear reactors flown during the 1960s by NASA.
The SNAP program developed as a result of Project Feedback, a Rand Corporation study of reconnaissance satellites completed in 1954. As some of the proposed satellites had high power demands, some as high as a few kilowatts, the U.S. Atomic Energy Commission (AEC) requested a series of nuclear power-plant studies from industry in 1951. Completed in 1952, these studies determined that nuclear power plants were technically feasible for use on satellites.
In 1955, the AEC began two parallel SNAP nuclear power projects. One, contracted with The Martin Company, used radio-isotopic decay as the power source for its generators. These plants were given odd-numbered SNAP designations beginning with SNAP-1. The other project used nuclear reactors to generate energy, and was developed by the Atomics International Division of North American Aviation. Their systems were given even-numbered SNAP designations, the first being SNAP-2.
Most of the systems development and reactor testing was conducted at the Santa Susana Field Laboratory, Ventura County, California using a number of specialized facilities.
Odd-numbered SNAPs: radioisotope thermoelectric generators
Radioisotope thermoelectric generators use the heat of radioactive decay to produce electricity.
SNAP-1
SNAP-1 was a test platform that was never deployed, using cerium-144 in a Rankine cycle with mercury as the heat transfer fluid. Operated successfully for 2500 hours.
SNAP-3
SNAP-3 was the first RTG used in a space mission (1961). Launched aboard U.S. Navy Transit 4A and 4B navigation satellites. The electrical output of this RTG was 2.5 watts.
SNAP-7
SNAP-7A, D and F was designed for marine applications such as lighthouses and buoys; at least six units were deployed in the mid-1960s, with names SNAP-7A through SNAP-7F. SNAP-7D pr
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https://en.wikipedia.org/wiki/Cap%20product
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In algebraic topology the cap product is a method of adjoining a chain of degree p with a cochain of degree q, such that q ≤ p, to form a composite chain of degree p − q. It was introduced by Eduard Čech in 1936, and independently by Hassler Whitney in 1938.
Definition
Let X be a topological space and R a coefficient ring. The cap product is a bilinear map on singular homology and cohomology
defined by contracting a singular chain with a singular cochain by the formula:
Here, the notation indicates the restriction of the simplicial map to its face spanned by the vectors of the base, see Simplex.
Interpretation
In analogy with the interpretation of the cup product in terms of the Künneth formula, we can explain the existence of the cap product in the following way. Using CW approximation we may assume that is a CW-complex and (and ) is the complex of its cellular chains (or cochains, respectively). Consider then the composition
where we are taking tensor products of chain complexes, is the diagonal map which induces the map
on the chain complex, and is the evaluation map (always 0 except for ).
This composition then passes to the quotient to define the cap product , and looking carefully at the above composition shows that it indeed takes the form of maps , which is always zero for .
Fundamental Class
For any point in , we have the long-exact sequence in homology (with coefficients in ) of the pair (M, M - {x}) (See Relative homology)
An element of is called the fundamental class for if is a generator of . A fundamental class of exists if is closed and R-orientable. In fact, if is a closed, connected and -orientable manifold, the map is an isomorphism for all in and hence, we can choose any generator of as the fundamental class.
Relation with Poincaré duality
For a closed -orientable n-manifold with fundamental class in (which we can choose to be any generator of ), the cap product map
is an isomorphism for all . This result i
|
https://en.wikipedia.org/wiki/John%20Billingham
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Dr. John Billingham, BM BCh, (March 18, 1930 – August 4, 2013) was a British Physician and later director of the SETI Program Office and Director of the Life Sciences Division at the NASA Ames Research Center in the USA. After retiring from NASA he became a Trustee of the SETI Institute Board of Directors.
He was born in Worcester, England in 1930 and educated at the Royal Grammar School Worcester. From there he went on to University College, Oxford to study physiology. He gained a BM BCh degree from Oxford and Guy's Hospital, London (which is equivalent to an M.D. in the US). He served as a medical officer with the Royal Air Force (RAF) for seven years, rising to the rank of Squadron Leader (equivalent to Major in the USAF). In 1963, he was invited to join NASA’s Lyndon B. Johnson Space Center in Houston, Texas, where he headed the Environmental Physiology Branch, and worked on the Mercury, Gemini and Apollo programs.
In 1965 he moved to the NASA Ames Research Center in California, where he headed up the Biotechnology Division, then the Extraterrestrial Research Division, and later the Life Science Division. In 1977 he appeared in the television documentary Mysteries of the Gods hosted by William Shatner to outline the projected search for extraterrestrial life that would later become Project Cyclops.
In 2009 he was inducted into the NASA Ames Hall of Fame where he was recognized for his efforts as the Father of SETI in NASA. After retiring from NASA he joined the SETI Institute as Senior Scientist, and in 1995 he became a Member of the SETI Institute's Board of Trustees, serving a term as Vice-Chair. He was also one of the people behind Project Cyclops.
He died at the age of 83 in Grass Valley, California in August 2013.
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https://en.wikipedia.org/wiki/Uniqueness%20theorem%20for%20Poisson%27s%20equation
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The uniqueness theorem for Poisson's equation states that, for a large class of boundary conditions, the equation may have many solutions, but the gradient of every solution is the same. In the case of electrostatics, this means that there is a unique electric field derived from a potential function satisfying Poisson's equation under the boundary conditions.
Proof
The general expression for Poisson's equation in electrostatics is
where is the electric potential and is the charge distribution over some region with boundary surface .
The uniqueness of the solution can be proven for a large class of boundary conditions as follows.
Suppose that we claim to have two solutions of Poisson's equation. Let us call these two solutions and . Then
and
It follows that is a solution of Laplace's equation, which is a special case of Poisson's equation that equals to . Subtracting the two solutions above gives
By applying the vector differential identity we know that
However, from () we also know that throughout the region Consequently, the second term goes to zero and we find that
By taking the volume integral over the region , we find that
By applying the divergence theorem, we rewrite the expression above as
We now sequentially consider three distinct boundary conditions: a Dirichlet boundary condition, a Neumann boundary condition, and a mixed boundary condition.
First, we consider the case where Dirichlet boundary conditions are specified as on the boundary of the region. If the Dirichlet boundary condition is satisfied on by both solutions (i.e., if on the boundary), then the left-hand side of () is zero. Consequently, we find that
Since this is the volume integral of a positive quantity (due to the squared term), we must have at all points. Further, because the gradient of is everywhere zero and is zero on the boundary, must be zero throughout the whole region. Finally, since throughout the whole region, and since throughout the whole regi
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https://en.wikipedia.org/wiki/A%20Scientific%20Support%20for%20Darwinism
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A Scientific Support for Darwinism (And For Public Schools Not To Teach "Intelligent Design" As Science) was a four-day, word-of-mouth petition of scientists in support of evolution. Inspired by Project Steve, it was initiated in 2005 by archaeologist R. Joe Brandon to produce a public response to the Discovery Institute's 2001 petition A Scientific Dissent From Darwinism.
The Discovery Institute's petition was publicized in 2005 by media coverage of the Discovery Institute's efforts to introduce intelligent design in science classrooms and the opposition to those efforts in the Kitzmiller v. Dover Area School District case. Brandon noticed that only about 80 of those appearing on the Dissent petition had expertise in an area relevant to evolution. Therefore, Brandon decided to create a petition of his own of scientists supporting evolution. The petition was hosted at ShovelBums.org, but has since been removed from the site.
A total of 7,733 scientists signed a statement affirming their support for evolution over a four-day period.
Statement
The statement was entitled A Scientific Support for Darwinism And For Public Schools Not To Teach "Intelligent Design" As Science, and read:
Results
In four days in the fall of 2005, starting on September 28, 2005, and ending at 4:09 pm Eastern Time, October 1, 2005, the petition supporting "Darwinism" gathered 7,733 verified signatures from concerned scientists. Of these, 6,965 were US residents and 4,066 had PhDs. The "Four Day Petition" was carried out with no outside funding or assistance of any professional society. The effort was carried out by email and word-of-mouth.
Among the signatories were 21 U.S. National Academy of Sciences members, nine MacArthur Fellowship awardees, and a Nobel laureate. According to Brandon's analysis, of those who signed his petition, there were
3,385 with biology in their title
850 with anthropology/archaeology
680 with evolutionary & ecology
394 from the field of genetics
270 from geol
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https://en.wikipedia.org/wiki/Rheobase
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Rheobase is a measure of membrane potential excitability. In neuroscience, rheobase is the minimal current amplitude of infinite duration (in a practical sense, about 300 milliseconds) that results in the depolarization threshold of the cell membranes being reached, such as an action potential or the contraction of a muscle. In Greek, the root rhe translates to "current or flow", and basi means "bottom or foundation": thus the rheobase is the minimum current that will produce an action potential or muscle contraction.
Rheobase can be best understood in the context of the strength-duration relationship (Fig. 1). The ease with which a membrane can be stimulated depends on two variables: the strength of the stimulus, and the duration for which the stimulus is applied. These variables are inversely related: as the strength of the applied current increases, the time required to stimulate the membrane decreases (and vice versa) to maintain a constant effect. Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a strength-duration time constant that corresponds to the duration of time that elicits a response when the nerve is stimulated at twice rheobasic strength.
The strength-duration curve was first discovered by G. Weiss in 1901, but it was not until 1909 that Louis Lapicque coined the term rheobase. Many studies are being conducted in relation to rheobase values and the dynamic changes throughout maturation and between different nerve fibers. In the past strength-duration curves and rheobase determinations were used to assess nerve injury; today, they play a role in clinical identification of many neurological pathologies, including diabetic neuropathy, CIDP, Machado–Joseph disease, and ALS.
Strength-Duration Curve
The strength-duration time constant (chronaxie) and rheobase are parameters that describe the strength-duration curve—the curve that relates the intensity of a threshold stimulus to i
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https://en.wikipedia.org/wiki/Static%20key
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A cryptographic key is called static if it is intended for use for a relatively long period of time and is typically intended for use in many instances of a cryptographic key establishment scheme. Contrast with an ephemeral key.
See also
Cryptographic key types
Recommendation for Key Management — Part 1: general,
NIST Cryptographic Toolkit
Key management
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https://en.wikipedia.org/wiki/Radar%20tracker
|
A radar tracker is a component of a radar system, or an associated command and control (C2) system, that associates consecutive radar observations of the same target into tracks. It is particularly useful when the radar system is reporting data from several different targets or when it is necessary to combine the data from several different radars or other sensors.
Role of the radar tracker
A classical rotating air surveillance radar system detects target echoes against a background of noise. It reports these detections (known as "plots") in polar coordinates representing the range and bearing of the target. In addition, noise in the radar receiver will occasionally exceed the detection threshold of the radar's Constant false alarm rate detector and be incorrectly reported as targets (known as false alarms). The role of the radar tracker is to monitor consecutive updates from the radar system (which typically occur once every few seconds, as the antenna rotates) and to determine those sequences of plots belonging to the same target, whilst rejecting any plots believed to be false alarms. In addition, the radar tracker is able to use the sequence of plots to estimate the current speed and heading of the target. When several targets are present, the radar tracker aims to provide one track for each target, with the track history often being used to indicate where the target has come from.
When multiple radar systems are connected to a single reporting post, a multiradar tracker is often used to monitor the updates from all of the radars and form tracks from the combination of detections. In this configuration, the tracks are often more accurate than those formed from single radars, as a greater number of detections can be used to estimate the tracks.
In addition to associating plots, rejecting false alarms and estimating heading and speed, the radar tracker also acts as a filter, in which errors in the individual radar measurements are smoothed out. In essenc
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https://en.wikipedia.org/wiki/Technology%20CAD
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Technology computer-aided design (technology CAD or TCAD) is a branch of electronic design automation that models semiconductor fabrication and semiconductor device operation. The modeling of the fabrication is termed Process TCAD, while the modeling of the device operation is termed Device TCAD. Included are the modelling of process steps (such as diffusion and ion implantation), and modelling of the behavior of the electrical devices based on fundamental physics, such as the doping profiles of the devices. TCAD may also include the creation of compact models (such as the well known SPICE transistor models), which try to capture the electrical behavior of such devices but do not generally derive them from the underlying physics. SPICE simulator itself is usually considered as part of ECAD rather than TCAD.
Introduction
Technology files and design rules are essential building blocks of the integrated circuit design process. Their accuracy and robustness over process technology, its variability and the operating conditions of the IC — environmental, parasitic interactions and testing, including adverse conditions such as electro-static discharge — are critical in determining performance, yield and reliability. Development of these technology and design rule files involves an iterative process that crosses boundaries of technology and device development, product design and quality assurance. Modeling and simulation play a critical role in support of many aspects of this evolution process.
The goals of TCAD start from the physical description of integrated circuit devices, considering both the physical configuration and related device properties, and build the links between the broad range of physics and electrical behavior models that support circuit design. Physics-based modeling of devices, in distributed and lumped forms, is an essential part of the IC process development. It seeks to quantify the underlying understanding of the technology and abstract tha
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https://en.wikipedia.org/wiki/Chronaxie
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Chronaxie is the minimum time required for an electric current double the strength of the rheobase to stimulate a muscle or a neuron. Rheobase is the lowest intensity with indefinite pulse duration which just stimulated muscles or nerves. Chronaxie is dependent on the density of voltage-gated sodium channels in the cell, which affect that cell’s excitability. Chronaxie varies across different types of tissue: fast-twitch muscles have a lower chronaxie, slow-twitch muscles have a higher one. Chronaxie is the tissue-excitability parameter that
permits choice of the optimum stimulus pulse duration for stimulation of any excitable tissue. Chronaxie (c) is the Lapicque descriptor of the stimulus pulse duration for a current
of twice rheobasic (b) strength, which is the threshold current
for an infinitely long-duration stimulus pulse. Lapicque showed
that these two quantities (c,b) define the strength-duration curve
for current: I = b(1+c/d), where d is the pulse duration.
However, there are two other electrical parameters used to
describe a stimulus: energy and charge. The minimum energy
occurs with a pulse duration equal to chronaxie. Minimum
charge (bc) occurs with an infinitely short-duration pulse.
Choice of a pulse duration equal to 10c requires a current of
only 10% above rheobase (b). Choice of a pulse duration of
0.1c requires a charge of 10% above the minimum charge (bc).
History
The terms chronaxie and rheobase were first coined in Louis Lapicque’s famous paper on Définition expérimentale de l’excitabilité that was published in 1909.
The above I(d) curve is usually attributed to Weiss (1901) - see e.g. (Rattay 1990).
It is the most simplistic of the 2 'simple' mathematical descriptors of the dependence of current strength on duration, and it leads to Weiss' linear charge progression with d:
Both Lapicque's own writings and more recent work are at odds with the linear-charge approximation.
Already in 1907 Lapicque was using a linear first-order approximation
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