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Tumor hypoxia is the situation where tumor cells have been deprived of oxygen. As a tumor grows, it rapidly outgrows its blood supply, leaving portions of the tumor with regions where the oxygen concentration is significantly lower than in healthy tissues. Hypoxic microenvironements in solid tumors are a result of available oxygen being consumed within 70 to 150 μm of tumour vasculature by rapidly proliferating tumor cells thus limiting the amount of oxygen available to diffuse further into the tumor tissue. In order to support continuous growth and proliferation in challenging hypoxic environments, cancer cells are found to alter their metabolism. Furthermore, hypoxia is known to change cell behavior and is associated with extracellular matrix remodeling and increased migratory and metastatic behavior. A particular change in metabolism, historically known as the Warburg effect results in high rates of glycolysis in both normoxic and hypoxic cancer cells. Expression of genes responsible for glycolytic enzymes and glucose transporters are enhanced by numerous oncogenes including RAS, SRC, and MYC. Traditionally, hypoxia leads to increased production of hypoxia-inducible factor (HIF-1), containing HIF-1α and HIF-1β subunits, that acts as a key regulatory transcription factor responsible for adaptive cellular changes. In humans, HIF-1 has been shown to up-regulate expression of genes affecting a range of target areas of physiology | https://en.wikipedia.org/wiki?curid=438610 | 68,321 |
Brewer–Dobson circulation is a model of atmospheric circulation, proposed by Alan Brewer in 1949 and Gordon Dobson in 1956, which attempts to explain why tropical air has less ozone than polar air, even though the tropical stratosphere is where most atmospheric ozone is produced. It is a simple circulation model that posits the existence of a slow current in the winter hemisphere which redistributes air from the tropics to the extratropics. The is driven by atmospheric waves and may be speeding up due to climate change. | https://en.wikipedia.org/wiki?curid=18506435 | 15,655 |
Big Five (banks) In October 2007, TD purchased Commerce Bancorp, a medium-sized US bank with a strong branch network in the middle Atlantic and Florida. As of March 2008, their stated plan was to merge Commerce with their existing TD Banknorth subsidiary, calling the new bank TD Commerce Bank. However, "Commerce Bank" based in Worcester, Massachusetts challenged the new name. As a result, TD renamed its US banks TD Bank at end of 2009. TD is the sixth-largest bank by branch network in North America, after JPMorgan, Bank of America, Wells Fargo, PNC, and US Bank. It is also the largest foreign bank in the United States holding almost $200 billion (USD) in deposits. Canada's federal government has sole jurisdiction for banks according to the Canadian Constitution, specifically Section 91(15) of "The Constitution Act, 1867" (30 & 31 Victoria, c.3 (UK)), formerly known as the "British North America Act, 1867". Meanwhile, credit unions/caisses populaires, securities dealers and mutual funds are largely regulated by provincial governments. The main federal statute for the incorporation and regulation of banks, or "chartered banks", is the "Bank Act" (S.C. 1991, c.46), where Schedules I, II and III of this Act list all banks permitted to operate in Canada under these three distinct categories. | https://en.wikipedia.org/wiki?curid=825745 | 477,006 |
Grey relational analysis , "The Journal of Grey System" (UK), "Grey Systems Theory and Application" (Emerald Group Publishing), "Journal of Grey System" (Taiwan), "Grey Room" (MIT Press), "The Grey Journal", "Grey Matters", Journal of Intelligent and Fuzzy Systems, Kybernetes, etc. | https://en.wikipedia.org/wiki?curid=20748374 | 398,292 |
Brushed DC electric motor The AC supply is used to drive an AC motor, usually an induction motor that drives a DC generator or dynamo. The DC output from the armature is directly connected to the armature of the DC motor (sometimes but not always of identical construction). The shunt field windings of both DC machines are independently excited through variable resistors. Extremely good speed control from standstill to full speed, and consistent torque, can be obtained by varying the generator and/or motor field current. This method of control was the "de facto" method from its development until it was superseded by solid state thyristor systems. It found service in almost any environment where good speed control was required, from passenger lifts through to large mine pit head winding gear and even industrial process machinery and electric cranes. Its principal disadvantage was that three machines were required to implement a scheme (five in very large installations, as the DC machines were often duplicated and controlled by a tandem variable resistor). In many applications, the motor-generator set was often left permanently running, to avoid the delays that would otherwise be caused by starting it up as required. Although electronic (thyristor) controllers have replaced most small to medium Ward-Leonard systems, some very large ones (thousands of horsepower) remain in service | https://en.wikipedia.org/wiki?curid=10004115 | 388,521 |
Astrophysical maser This latter obstacle may be partially surmounted through the judicious use of the spatial filtering inherent in interferometric techniques, especially very long baseline interferometry (VLBI). The major use of maser study is that they give valuable information on the conditions in space, such as temperature, number density, magnetic field, and velocity, in the most interesting of environments — including stellar birth and death, and the centres of galaxies containing black holes. The conditions involved in these events still need more accurate measuring so that theoretical models can be refined or revised. In 1965 an unexpected discovery was made by Weaver "et al.": emission lines in space, of unknown origin, at a frequency of 1665 MHz. At this time many researchers still thought that molecules could not exist in space, even though they had been discovered by McKellar in the 1940's (https://en.wikipedia.org/wiki/Andrew_McKellar) , and so the emission was at first attributed to an unknown form of interstellar matter named "Mysterium", but the emission was soon identified as line emission from OH molecules in compact sources within molecular clouds. More discoveries followed, with HO emission in 1969, CHOH emission in 1970 and SiO emission in 1974, all coming from within molecular clouds. These were termed "masers", as from their narrow line-widths and high effective temperatures it became clear that these sources were amplifying microwave radiation | https://en.wikipedia.org/wiki?curid=3618030 | 74,827 |
Water-gas shift reaction To shift the equilibrium toward hydrogen production, a subsequent low temperature shift reactor is employed to produce a carbon monoxide exit composition of less than 1%. The transition from the HTS to the LTS reactors necessitates intersystem cooling. Due to the different reaction conditions, different catalysts must be employed at each stage to ensure optimal activity. The commercial HTS catalyst is the iron oxide–chromium oxide catalyst and the LTS catalyst is a copper-based catalyst. The order proceeds from high to low temperature due to the susceptibility of the copper catalyst to poisoning by sulfur that may remain after the steam reformation process. This necessitates the removal of the sulfur compounds prior to the LTS reactor by a guard bed in order to protect the copper catalyst. Conversely, the iron used in the HTS reaction is generally more robust and resistant toward poisoning by sulfur compounds. While both the HTS and LTS catalysts are commercially available, their specific composition varies based on vendor. An important limitation for the HTS is the HO/CO ratio where low ratios may lead to side reactions such as the formation of metallic iron, methanation, carbon deposition, and the Fischer–Tropsch reaction. The typical composition of a commercial LTS catalyst has been reported as 32-33% CuO, 34-53% ZnO, 15-33% AlO. The active catalytic species is CuO. The function of ZnO is to provide structural support as well as prevent the poisoning of copper by sulfur | https://en.wikipedia.org/wiki?curid=1715834 | 85,872 |
Sum rule in quantum mechanics In quantum mechanics, a sum rule is a formula for transitions between energy levels, in which the sum of the transition strengths is expressed in a simple form. Sum rules are used to describe the properties of many physical systems, including solids, atoms, atomic nuclei, and nuclear constituents such as protons and neutrons. The sum rules are derived from general principles, and are useful in situations where the behavior of individual energy levels is too complex to be described by a precise quantum-mechanical theory. In general, sum rules are derived by using Heisenberg's quantum-mechanical algebra to construct operator equalities, which are then applied to the particles or energy levels of a system. Assume that the Hamiltonian formula_1 has a complete set of eigenfunctions formula_2 with eigenvalues formula_3: For the Hermitian operator formula_5 we define the repeated commutator formula_6 iteratively by: The operator formula_8 is Hermitian since formula_5 is defined to be Hermitian. The operator formula_10 is anti-Hermitian: By induction one finds: and also For a Hermitian operator we have Using this relation we derive: The result can be written as For formula_17 this gives: See oscillator strength. | https://en.wikipedia.org/wiki?curid=18176029 | 426,848 |
Digital storage oscilloscope Digital oscilloscopes usually analyze waveforms and provide numerical values as well as visual displays. These values typically include averages, maxima and minima, root mean square (RMS) and frequencies. They may be used to capture transient signals when operated in a single sweep mode, without the brightness and writing speed limitations of an analog storage oscilloscope. The displayed trace can be manipulated after acquisition; a portion of the display can be magnified to make fine detail more visible, or a long trace can be examined in a single display to identify areas of interest. Many instruments allow a stored trace to be annotated by the user. Many digital oscilloscopes use flat panel displays similar to those made in high volumes for computers and television displays. | https://en.wikipedia.org/wiki?curid=33353907 | 378,555 |
Calculation of glass properties The calculation of glass properties (glass modeling) is used to predict glass properties of interest or glass behavior under certain conditions (e.g., during production) without experimental investigation, based on past data and experience, with the intention to save time, material, financial, and environmental resources, or to gain scientific insight. It was first practised at the end of the 19th century by A. Winkelmann and O. Schott. The combination of several glass models together with other relevant functions can be used for optimization and six sigma procedures. In the form of statistical analysis glass modeling can aid with accreditation of new data, experimental procedures, and measurement institutions (glass laboratories). Historically, the calculation of glass properties is directly related to the founding of glass science. At the end of the 19th century the physicist Ernst Abbe developed equations that allow calculating the design of optimized optical microscopes in Jena, Germany, stimulated by co-operation with the optical workshop of Carl Zeiss. Before Ernst Abbe's time the building of microscopes was mainly a work of art and experienced craftsmanship, resulting in very expensive optical microscopes with variable quality. Now Ernst Abbe knew exactly how to construct an excellent microscope, but unfortunately, the required lenses and prisms with specific ratios of refractive index and dispersion did not exist | https://en.wikipedia.org/wiki?curid=13803804 | 203,929 |
In-circuit emulation Most ICEs consist of an adaptor unit that sits between the ICE host computer and the system to be tested. A pin header and cable assembly connects the adaptor to a socket where the actual central processing unit (CPU) or microcontroller mounts within the embedded system. Recent ICEs enable programmers to access the on-chip debug circuit that is integrated into the CPU via JTAG or background debug mode interface (BDM) to debug the software of an embedded system. These systems often use a standard version of the CPU chip, and can simply attach to a debug port on a production system. They are sometimes called in-circuit debuggers or ICDs, to distinguish the fact that they do not replicate the functionality of the CPU, but instead control an already existing, standard CPU. Since the CPU need not be replaced, they can operate on production units where the CPU is soldered in and cannot be replaced. On x86 Pentiums, a special 'probe mode' is used by ICEs to aid in debugging. In the context of embedded systems, the ICE is not emulating hardware. Rather, it is providing direct debug access to the actual CPU. The system under test is under full control, allowing the developer to load, debug and test code directly. Most host systems are ordinary commercial computers unrelated to the CPU used for development. For example, a Linux PC might be used to develop software for a system using a Freescale 68HC11 chip, a processor that cannot run Linux | https://en.wikipedia.org/wiki?curid=291590 | 130,911 |
DNA damage theory of aging (1924–1993) theorized and presented evidence that cells undergo "irreparable DNA damage", whereby DNA crosslinks occur when both normal cellular repair processes fail and cellular apoptosis does not occur. Specifically, Acharya noted that double-strand breaks and a "cross-linkage joining both strands at the same point is irreparable because neither strand can then serve as a template for repair. The cell will die in the next mitosis or in some rare instances, mutate." In tissues composed of non- or infrequently replicating cells, DNA damage can accumulate with age and lead either to loss of cells, or, in surviving cells, loss of gene expression. Accumulated DNA damage is usually measured directly. Numerous studies of this type have indicated that oxidative damage to DNA is particularly important. The loss of expression of specific genes can be detected at both the mRNA level and protein level. The adult brain is composed in large part of terminally differentiated non-dividing neurons. Many of the conspicuous features of aging reflect a decline in neuronal function. Accumulation of DNA damage with age in the mammalian brain has been reported during the period 1971 to 2008 in at least 29 studies. This DNA damage includes the oxidized nucleoside 8-oxo-2'-deoxyguanosine (8-oxo-dG), single- and double-strand breaks, DNA-protein crosslinks and malondialdehyde adducts (reviewed in Bernstein et al.). Increasing DNA damage with age has been reported in the brains of the mouse, rat, gerbil, rabbit, dog, and human | https://en.wikipedia.org/wiki?curid=17062920 | 171,929 |
Burst switching In a packet switched network, burst switching is a capability in which each network switch extracts routing instructions from an incoming packet header to establish and maintain the appropriate switch connection for the duration of the packet, following which the connection is automatically released. In concept, burst switching is similar to connectionless mode transmission, but differs in that burst switching implies an intent to establish the switch connection in near real time so that only minimum buffering is required at the node switch. A variant of burst switching used in optical networks is optical burst switching. | https://en.wikipedia.org/wiki?curid=40822 | 114,338 |
Nickel titanium Buehler was attempting to make a better missile nose cone, which could resist fatigue, heat and the force of impact. Having found that a 1:1 alloy of nickel and titanium could do the job, in 1961 he presented a sample at a laboratory management meeting. The sample, folded up like an accordion, was passed around and flexed by the participants. One of them applied heat from his pipe lighter to the sample and, to everyone's surprise, the accordion-shaped strip contracted and took its previous shape. While the potential applications for nitinol were realized immediately, practical efforts to commercialize the alloy did not take place until a decade later. This delay was largely because of the extraordinary difficulty of melting, processing and machining the alloy. Even these efforts encountered financial challenges that were not readily overcome until the 1980s, when these practical difficulties finally began to be resolved. The discovery of the shape-memory effect in general dates back to 1932, when Swedish chemist Arne Ölander first observed the property in gold-cadmium alloys. The same effect was observed in Cu-Zn (brass) in the early 1950s. Nitinol's unusual properties are derived from a reversible solid-state phase transformation known as a martensitic transformation, between two different martensite crystal phases, requiring of mechanical stress. At high temperatures, nitinol assumes an interpenetrating simple cubic structure referred to as austenite (also known as the parent phase) | https://en.wikipedia.org/wiki?curid=8305325 | 356,900 |
Reverse Transcription Loop-mediated Isothermal Amplification This structure becomes a stem-loop when the FIP or BIP primer once again initiates DNA synthesis at one of the target sequence locations. This cycle can be started from either the forward or backward side of the strand using the appropriate primer. Once this cycle has begun, the strand undergoes self-primed DNA synthesis during the elongation stage of the amplification process. This amplification takes place in only an hour, under isothermal conditions between 60-65 °C. This method is specifically advantageous because it can all be done quickly in one step. The sample is mixed with the primers, reverse transcriptase and DNA polymerase and the reaction takes place under a constant temperature. The required temperature is so low that the reaction can be completed using a simple hot water bath. There is no need for expensive thermocycling equipment that is necessary for other methods like PCR, which makes RT-LAMP very cost effective. In contrast with conventional PCR and real-time PCR assays, this method is much more efficient while still obtaining a high level of precision. This inexpensive and streamlined method can be more readily used in developing countries that do not have access to high tech laboratories. These areas are known for having a multitude of infectious diseases caused by various bacteria and viruses. The LAMP method is very useful for detection of these pathogens. A disadvantage of this method is generating the sequence specific primers | https://en.wikipedia.org/wiki?curid=42447237 | 20,950 |
Friedrich-von-Raumer-Bibliothek IV moved into a new location on Ritterstraße 31, only to move again into Berlin's 47th and 7th municipal school (47. und 7. Gemeindeschule) on Stallschreiberstraße 54a in 1877, both in what became Kreuzberg after 1920. Tradespeople and craftspeople made up for most users, the number of workers among the users rose between 1867 and 1877, but was still below a third in 1877. The number of youth among the users had risen by the time since Berlin's public libraries then had also started to hold media of their interest. In 1878 Fidicin retired. In the 1880s the development of the libraries stagnated. Budgets for new books were too short, as were the opening hours, librarian consulting was too poor and access too restricted. In 1886 in an article in the "Zentralblatt für Bibliothekswesen" the Austrian professor shed light on the successful work of US American libraries, giving the central European library landscape a new push | https://en.wikipedia.org/wiki?curid=41218254 | 327,467 |
Resilient control systems Therefore, in considering resilient control system architecture, atypical designs that imbed active and passively implemented randomization of attributes, would be suggested to reduce this advantage. While much of the current critical infrastructure is controlled by a web of interconnected control systems, either architecture termed as distributed control systems (DCS) or supervisory control and data acquisition (SCADA), the application of control is moving toward a more decentralized state. In moving to a smart grid, the complex interconnected nature of individual homes, commercial facilities and diverse power generation and storage creates an opportunity and a challenge to ensuring that the resulting system is more resilient to threats. The ability to operate these systems to achieve a global optimum for multiple considerations, such as overall efficiency, stability and security, will require mechanisms to holistically design complex networked control systems. Multi-agent methods suggest a mechanism to tie a global objective to distributed assets, allowing for management and coordination of assets for optimal benefit and semi-autonomous, but constrained controllers that can react rapidly to maintain resilience for rapidly changing conditions. Establishing a metric that can capture the resilience attributes can be complex, at least if considered based upon differences between the interactions or interdependencies | https://en.wikipedia.org/wiki?curid=22982978 | 131,246 |
Willcox Women's Club The was incorporated in 1916 which allowed the club to own property. The club was a member of the Arizona State Federation of Women's Clubs. The raised money during the 1920s to build the clubhouse, and donated land to the city in a deal for the Works Progress Administration to build the building. The at 312 W. Stewart in Willcox, Arizona, was a W.P.A. project begun in 1934 and completed in 1936. It was listed on the National Register of Historic Places in 1987. It was deemed significant as the only example of Pueblo Revival style in Willcox. The building is also referred to as the Willcox Women's Community Center. | https://en.wikipedia.org/wiki?curid=58897831 | 306,151 |
Discovery and development of NS5A inhibitors The combination of NS5A and NS5B inhibitors has produced positive results in this regard. The discovery of NS5A inhibitors took place within the context of a pursuit for a treatment for HCV. NS5A is among the seven nonstructural proteins that form a complex with viral RNA within infected cells to initiate HCV replication. HCV research has produced several DAAs including NS3A, NS4A and NS5B inhibitors, as well as NS5A inhibitors. The development of antiviral drugs capable of interfering with the proteins responsible for viral replication has been intimately linked with advancements in techniques for establishing the efficient cell culture systems needed to screen for them. In 1999 a breakthrough came when a full-length consensus genome cloned from HCV RNA was found to replicate at high levels when transfected into a human hepatoma cell line. This method has since been improved upon with the use of cell culture-adaptive mutations that enhance RNA replication. Screening has now produced a number of NS5A inhibitors, which have been incorporated into treatments for HCV. The first in this new class of drugs was daclatasvir, which received FDA approval in 2015. Other drugs have since been approved, among them notably ledipasvir, which, along with sofosbuvir comprise the HCV drug Harvoni. Although NS5A inhibitors have proven effective antivirals, they must be used alongside complementary antiviral drugs due to how quickly they lead to the development of resistant mutations when given as a single agent | https://en.wikipedia.org/wiki?curid=51779654 | 54,028 |
Feature connector Unlike analog overlay devices however, a feature connector carried mainly data and essentially allowed an expansion card to access the graphics card Video RAM directly, although directing this data stream to the system's CPU and RAM was not always possible, limiting its usefulness mainly to display purposes. Although its use rapidly declined after the introduction of the faster AGP internal bus, it was, at its time, the only feasible way to connect certain types of graphics-intensive devices to an average computing system without exceeding the available CPU power and memory bandwidth, and without the disadvantages and limitations of a purely analog overlay. The idea of accessing a video card's memory directly resurfaced with the introduction of the Scan-Line Interleave (3dfx SLI) technology, although this technology is aimed at connecting two equally powered and complete graphic cards to produce a single, increased performance visual output, and not e.g. directly interfacing TV tuner cards. | https://en.wikipedia.org/wiki?curid=2629937 | 416,014 |
Protein skimmer This was one of the earlier high performance protein skimmer designs and large models were produced that saw success in large and public aquariums. The Beckett skimmer has some similarities to the downdraft skimmer but introduced a foam nozzle to produce the flow of air bubbles. The name Beckett comes from the patented foam nozzle developed and sold by the Beckett Corporation (United States), although similar foam nozzle designs are sold by other companies outside the United States (e.g. Sicce (Italy)). Instead of using the plastic media that is found in downdraft skimmer designs, the Beckett skimmer uses design concepts from previous generations of skimmers, specifically the downdraft skimmer and the venturi skimmer (the Beckett 1408 Foam Nozzle is a modified 4 port venturi) to produce a hybrid that is capable of using powerful pressure rated water pumps and quickly processing large amounts of aquarium water in a short period of time. Commercial Beckett skimmers come in single Beckett, dual Beckett, and quad Beckett designs. Well engineered Beckett skimmers are quiet and reliable but the powerful pumps used in larger Beckett skimmer designs can take up additional space, introduce additional noise, and use more electricity than less powerful pumps. Unlike the Downdraft and Spray Induction skimmers, Beckett skimmer designs are produced by a number of companies in the United States and elsewhere and are not known to be restricted by patents | https://en.wikipedia.org/wiki?curid=1158875 | 50,673 |
Grigory Yavlinsky But despite Bush's administration 750 billion and Obama's 800 billion dollars investments nothing changed, economic activity wasn't growing because of markets' distrust. In his recent book "Realeconomik: The Hidden Cause of the Great Recession (and How to Avert the Next One)", the internationally respected economist makes a powerful case that without a commitment to established social principles in business and politics, a stable global economy will be impossible to achieve: Yavlinsky argues against viewing the world of money as separate from culture and society: he believes the financial crisis was merely a symptom of a wider moral collapse, and that it is time to examine the way we live. Yavlinsky attempted to run for president again in the 2012 election. Days after Yavlinsky's candidature was endorsed by Gorbachev, the National Electoral Commission (NEC) declared 20% of the signatures collected in support of the leader of Yabloko invalid. Commenting on the incident at a news Conference Yavlinsky said: 'I consider the decision of the NEC as politically motivated. They aren't letting me join the race, because they don't want to allow an alternative - political, economic and moral.' He also cautioned that such refusal to allow him to join the race would undermine the vote's legitimacy and could lead to unrest and instability in the country. Yavlinsky needed to collect and submit at least 2,000,000 votes in order to register since he was nominated by a non-parliamentary party | https://en.wikipedia.org/wiki?curid=613433 | 37,211 |
Vulnerability of nuclear plants to attack Nuclear reactors become preferred targets during military conflict and, over the past three decades, have been repeatedly attacked during military air strikes, occupations, invasions and campaigns. Various acts of civil disobedience since 1980 by the peace group Plowshares have shown how nuclear weapons facilities can be penetrated, and the group's actions represent extraordinary breaches of security at nuclear weapons plants in the United States. The National Nuclear Security Administration has acknowledged the seriousness of the 2012 Plowshares action. Non-proliferation policy experts have questioned "the use of private contractors to provide security at facilities that manufacture and store the government's most dangerous military material". Nuclear weapons materials on the black market are a global concern,<ref name="A Nuclear 9/11">Brian Michael Jenkins. A Nuclear 9/11? "CNN.com", September 11, 2008.</ref> and there is concern about the possible detonation of a dirty bomb by a militant group in a major city. The number and sophistication of cyber attacks is on the rise. "Stuxnet" is a computer worm discovered in June 2010 that is believed to have been created by the United States and Israel to attack Iran's nuclear facilities. It switched off safety devices, causing centrifuges to spin out of control. The computers of South Korea's nuclear plant operator (KHNP) were hacked in December 2014. The cyber attacks involved thousands of phishing emails containing malicious code, and information was stolen | https://en.wikipedia.org/wiki?curid=40528380 | 274,421 |
Autopen On January 3, 2013, he signed the extension to the Bush tax cuts, using the while vacationing in Hawaii. In order to sign it by the required deadline, his other alternative would have been to have had the bill flown to him overnight. Republican leaders have questioned whether this use of the meets the Constitutional requirement for signing a bill into law, but the validity of presidential use of an autopen has not been actually tested in court. During his term in office, President George W. Bush asked for and received a favorable opinion from the Department of Justice regarding the constitutionality of using the autopen, but did not use it himself. Further developing the class of devices known as autopens, Canadian author Margaret Atwood created a device called the LongPen, which allows audio and video conversation between the fan and author while a book is being signed remotely. | https://en.wikipedia.org/wiki?curid=1204311 | 294,036 |
Minimally invasive education Describing current instructional methods as homogenization and lockstep standardization, alternative approaches are proposed, such as the Sudbury model schools, an alternative approach in which children, by enjoying personal freedom thus encouraged to exercise personal responsibility for their actions, learn at their own pace rather than following a chronologically-based curriculum. These schools are organized to allow freedom from adult interference in the daily lives of students. As long as children do no harm to others, they can do whatever they want with their time in school. The adults in other schools plan a curriculum of study, teach the students the material and then test and grade their learning. The adults at Sudbury schools are ""the guardians of the children's freedom to pursue their own interests and to learn what they wish,"" creating and maintaining a nurturing environment, in which children feel that they are cared for, and that does not rob children of their time to explore and discover their inner selves. They also are there to answer questions and to impart specific skills or knowledge when asked to by students. As Sudbury schools, proponents of unschooling have also claimed that children raised in this method do not suffer from learning disabilities, thus not requiring the prevention of academic failure through intervention. | https://en.wikipedia.org/wiki?curid=1010814 | 236,137 |
Energy operator Starting in one dimension the wave function is The time derivative of "Ψ" is By the De Broglie relation: we have Re-arranging the equation leads to where the energy factor "E" is a scalar value, the energy the particle has and the value that is measured. The partial derivative is a linear operator so this expression "is" the operator for energy: It can be concluded that the scalar "E" is the eigenvalue of the operator, while formula_16 is the operator. Summarizing these results: For a 3-d plane wave the derivation is exactly identical, as no change is made to the term including time and therefore the time derivative. Since the operator is linear, they are valid for any linear combination of plane waves, and so they can act on any wave function without affecting the properties of the wave function or operators. Hence this must be true for any wave function. It turns out to work even in relativistic quantum mechanics, such as the Klein–Gordon equation above. | https://en.wikipedia.org/wiki?curid=26356935 | 448,928 |
History of calendars Thirteen days were named after Fire, Water, Sun, Moon, Tiri and Geush Urvan (the soul of all animals), Mithra, Sraosha (Soroush, yazata of prayer), Rashnu (the Judge), Fravashi, Bahram (yazata of victory), Raman (Ramesh meaning peace), and Vata, the divinity of the wind. Three were dedicated to the female divinities, Daena (yazata of religion and personified conscious), Ashi (yazata of fortune) and Arshtat (justice). The remaining four were dedicated to Asman (lord of sky or Heaven), Zam (earth), Manthra Spenta (the Bounteous Sacred Word) and Anaghra Raocha (the 'Endless Light' of paradise). The Parthians (Arsacid dynasty) adopted the same calendar system with minor modifications, and dated their era from 248 BCE, the date they succeeded the Seleucids. Their names for the months and days are Parthian equivalents of the Avestan ones used previously, differing slightly from the Middle Persian names used by the Sassanians. For example, in Achaemenid times the modern Persian month 'Day' was called "Dadvah" (Creator), in Parthian it was "Datush", and the Sassanians named it "Dadv/Dai" ("Dadar" in Pahlavi). When in April of AD 224 the Parthian dynasty fell and was replaced by the Sasanid, the new king, Ardashir I, abolished the official Babylonian calendar and replaced it with the Zoroastrian. This involved a correction to the places of the "gahanbar", which had slipped back in the seasons since they were fixed | https://en.wikipedia.org/wiki?curid=295888 | 245,549 |
Asteroid mining On April 24, 2012 a plan was announced by billionaire entrepreneurs to mine asteroids for their resources. The company is called Planetary Resources and its founders include aerospace entrepreneurs Eric Anderson and Peter Diamandis. Advisers include film director and explorer James Cameron and investors include Google's chief executive Larry Page and its executive chairman Eric Schmidt. They also plan to create a fuel depot in space by 2020 by using water from asteroids, splitting it to liquid oxygen and liquid hydrogen for rocket fuel. From there, it could be shipped to Earth orbit for refueling commercial satellites or spacecraft. The plan has been met with skepticism by some scientists, who do not see it as cost-effective, even though platinum is worth $32 per gram and gold $49 per gram as of September 2019. Platinum and gold are raw materials traded on terrestrial markets, and it is impossible to predict what prices either will command at the point in the future when resources from asteroids become available. For example, platinum traditionally is very valuable due to its use in both industrial and jewelry applications, but should future technologies make the internal combustion engine obsolete, the demand for platinum's use as the catalyst in catalytic converters may well decline and decrease the metal's long term demand | https://en.wikipedia.org/wiki?curid=1667490 | 249,961 |
John Newlands (chemist) John Alexander Reina Newlands (26 November 1837 – 29 July 1898) was a British chemist who worked concerning the periodicity of elements. Newlands was born in London in England, at West Square in Lambeth, the son of a Scottish Presbyterian minister and his Italian wife. He was home-schooled by his father, and later studied at the Royal College of Chemistry. He was interested in social reform and during 1860 served as a volunteer with Giuseppe Garibaldi in his military campaign to unify Italy. Returning to London, Newlands established himself as an analytical chemist in 1864. In 1868 he became chief chemist of James Duncan's London sugar refinery, where he introduced a number of improvements in processing. Later he quit the refinery and again became an analyst with his brother, Benjamin. Newlands was the first person to devise a periodic table of chemical elements arranged in order of their relative atomic masses. Continuing Johann Wolfgang Döbereiner's work with triads and Jean-Baptiste Dumas' families of similar elements, he published in 1865 his 'Law of Octaves', which stated that 'any given element will exhibit analogous behaviour to the eighth element following it in the table. Newlands arranged all of the known elements, starting with hydrogen and ending with thorium (atomic weight 232), into eight groups of seven, which he likened to octaves of music. In Newlands' table, the elements were ordered by the atomic weights that were known at the time and were numbered sequentially to show their order | https://en.wikipedia.org/wiki?curid=228425 | 25,122 |
Biofeedback The 2008 edition reviewed the efficacy of biofeedback for over 40 clinical disorders, ranging from alcoholism/substance abuse to vulvar vestibulitis. The ratings for each disorder depend on the nature of research studies available on each disorder, ranging from anecdotal reports to double blind studies with a control group. Thus, a lower rating may reflect the lack of research rather than the ineffectiveness of biofeedback for the problem. The randomized trial by Dehli et al. compared if the injection of a bulking agent in the anal canal was superior to sphincter training with biofeedback to treat fecal incontinence. Both methods lead to an improvement of FI, but comparisons of St Mark's scores between the groups showed no differences in effect between treatments. Yucha and Montgomery's (2008) ratings are listed for the five levels of efficacy recommended by a joint Task Force and adopted by the Boards of Directors of the Association for Applied Psychophysiology (AAPB) and the International Society for Neuronal Regulation (ISNR). From weakest to strongest, these levels include: not empirically supported, possibly efficacious, probably efficacious, efficacious, and efficacious and specific. Level 1: Not empirically supported. This designation includes applications supported by anecdotal reports and/or case studies in non-peer-reviewed venues. Yucha and Montgomery (2008) assigned eating disorders, immune function, spinal cord injury, and syncope to this category. Level 2: Possibly efficacious | https://en.wikipedia.org/wiki?curid=292906 | 130,952 |
Vienna rectifier The Vienna Rectifier is a pulse-width modulation rectifier, invented in 1993 by Johann W. Kolar. Vienna Rectifier provides following features: The Vienna Rectifier is a unidirectional three-phase three-switch three-level Pulse-width modulation (PWM) rectifier. It can be seen as a three-phase diode bridge with an integrated boost converter. The Vienna Rectifier is useful wherever six-switch converters are used for achieving sinusoidal mains current and controlled output voltage, when no energy feedback from the load into the mains is available. In practice, use of the Vienna Rectifier is advantageous when space is at a sufficient premium to justify the additional hardware cost. These include: Figure 2 shows the top and bottom views of an air-cooled 10 kW-Vienna Rectifier (400 kHz PWM), with sinusoidal input current s and controlled output voltage. Dimensions are 250mm x 120mm x 40mm, resulting in a power density of 8.5 kW/dm. The total weight of the converter is 2.1 kg Figure 3 shows the system behavior, calculated using the power-electronics circuit simulator. Between the output voltage midpoint (0) and the mains midpoint (M) the common mode voltage u0M appears, as is characteristic in three-phase converter systems. It is possible to separately control the input current shape in each branch of the diode bridge by inserting a bidirectional switch into the node, as shown in Figure 3. The switch Ta controls the current by controlling the magnetization of the inductor | https://en.wikipedia.org/wiki?curid=23173874 | 392,894 |
Game theory Despite the name, evolutionary game theory does not necessarily presume natural selection in the biological sense. Evolutionary game theory includes both biological as well as cultural evolution and also models of individual learning (for example, fictitious play dynamics). Some scholars see game theory not as a predictive tool for the behavior of human beings, but as a suggestion for how people ought to behave. Since a strategy, corresponding to a Nash equilibrium of a game constitutes one's best response to the actions of the other players – provided they are in (the same) Nash equilibrium – playing a strategy that is part of a Nash equilibrium seems appropriate. This normative use of game theory has also come under criticism. is a major method used in mathematical economics and business for modeling competing behaviors of interacting agents. Applications include a wide array of economic phenomena and approaches, such as auctions, bargaining, mergers and acquisitions pricing, fair division, duopolies, oligopolies, social network formation, agent-based computational economics, general equilibrium, mechanism design, and voting systems; and across such broad areas as experimental economics, behavioral economics, information economics, industrial organization, and political economy. This research usually focuses on particular sets of strategies known as "solution concepts" or "equilibria". A common assumption is that players act rationally | https://en.wikipedia.org/wiki?curid=11924 | 135,500 |
Sulfur sticks are used in industrial ammonia refrigeration systems to detect minor ammonia leaks. A sulfur stick is made from a wick which contains particles of sulfur. The sulfur stick is lit and smolders, something like the taper that is used to light fireworks. The color of the sulfur smoke is used to find the leak. When there is no ammonia the smoke is colorless but when ammonia is present the combined sulfur and ammonia vapors produce a white smoke. have been used to find ammonia leaks for at least 100 years. | https://en.wikipedia.org/wiki?curid=2559292 | 373,808 |
History of contract law Private housing was subject to basic terms, such as the right to repairs, and restrictions on unfair rent increases, though many protection was abolished during the 1980s. This reduced the scope of the general law of contract, and meant that most contracts individual people made in their ordinary lives were shielded from the power of corporations to impose whatever terms they chose in selling goods and services, at work, and in people's home. Nevertheless, classical contract law remained at the foundation of specific contracts, unless particular rights were given by the courts or Parliament. Internationally, the UK had joined the European Union, which aimed to harmonise significant parts of consumer and employment law across member states. Moreover, with increasing openness of markets commercial contracts were receiving ideas from abroad. Both the Principles of European Contract Law, the UNIDROIT Principles of International Commercial Contracts, and the practice of international commercial arbitration was reshaping thinking about English contract principles with the rest of the globalising economy. | https://en.wikipedia.org/wiki?curid=40766467 | 487,646 |
Prestressed concrete Modern prestressing systems deliver long-term durability by addressing the following areas: Several durability-related events are listed below: is a highly versatile construction material as a result of it being an almost ideal combination of its two main constituents: high-strength steel, pre-stretched to allow its full strength to be easily realised; and modern concrete, pre-compressed to minimise cracking under tensile forces. Its wide range of application is reflected in its incorporation into the major design codes covering most areas of structural and civil engineering, including buildings, bridges, dams, foundations, pavements, piles, stadiums, silos, and tanks. Building structures are typically required to satisfy a broad range of structural, aesthetic and economic requirements. Significant among these include: a minimum number of (intrusive) supporting walls or columns; low structural thickness (depth), allowing space for services, or for additional floors in high-rise construction; fast construction cycles, especially for multi-storey buildings; and a low cost-per-unit-area, to maximise the building owner's return on investment. The prestressing of concrete allows "load-balancing" forces to be introduced into the structure to counter in-service loadings | https://en.wikipedia.org/wiki?curid=833499 | 216,792 |
Amy Chua Furthermore, the book provoked uproar after the release where Chua received death threats, racial slurs, and calls for her arrest on child-abuse charges. Her fourth book, co-written with husband Jed Rubenfeld, is "The Triple Package: How Three Unlikely Traits Explain the Rise and Fall of Cultural Groups in America" (published in February 2014). The book received positive reviews from a number of sources. Lucy Kellaway, writing for "Financial Times", called it "the best universal theory of success I've seen." "The Guardian" commended the book for "draw[ing] on eye-opening studies of the influence of stereotypes and expectations on various ethnic and cultural groups ... The authors' willingness to pursue an intellectual inquiry that others wouldn't is bracing." The book was also criticized because of what some described as cultural stereotyping. An empirical study by Joshua Hart and Christopher F. Chabris found that "There was little evidence for the Triple Package theory." Chua also appears in author J. D. Vance's memoir and bestseller, "Hillbilly Elegy". Chua's student at Yale, Vance wrote that she gave him "the best advice anyone has ever given me." Vance wrote in his acknowledgments, "Besides Tina, the person who deserves the most credit for this book's existence is Amy Chua, my Yale contracts professor, who convinced me that both my life and the conclusions I drew from it were worth putting down on paper." Vance credits Chua as the "authorial godmother" of "Hillbilly Elegy" | https://en.wikipedia.org/wiki?curid=6312536 | 499,566 |
IEEE Biometrics Council The is one of seven councils of the IEEE. The mission of the is as follows: "To advance and coordinate throughout IEEE, the work in the field of biometrics technologies and applications and to expand the IEEE's role in this interdisciplinary area. The fields of interest of the Council include the theory, design, and application of biometric characterization of human beings, based on physiological and/or behavioral features and traits, in particular for identification, identity verification, authentication, encryption, and recognition. The Council will promote technical activities, sponsor technical meetings and sessions, publish periodicals, promote educational activities, develop standards, and engage in any other activity defined within its field of interest." The Council is recognized for regularly sponsoring a number of international conferences year to year that focus on its mission. | https://en.wikipedia.org/wiki?curid=22799105 | 267,007 |
Lagrangian coherent structure This result applies both in two- and three dimensions, and enables the computation of a well-defined, objective and dynamically consistent material rotation angle along any trajectory. Outermost complex tubular level curves of the LAVD define initial positions of rotationally coherent material vortex boundaries in two-dimensional unsteady flows (see Fig. 11a). By construction, these boundaries may exhibit transverse filamentation, but any developing filament keeps rotating with the boundary, without global transverse departure form the material vortex. (Exceptions are inviscid flows where such a global departure of LAVD level surfaces from a vortex is possible as fluid elements preserve their material rotation rate for all times). Remarkably, centers of rotationally coherent vortices (defined by local maxima of the LAVD field) can be proven to be the observed centers of attraction or repulsion for finite-size (inertial) particle motion in geophysical flows (see Fig. 11b). In three-dimensional flows, tubular level surfaces of the LAVD define initial positions of two-dimensional eddy boundary surfaces (see Fig. 11c) that remain rotationally coherent over a time intcenter|erval formula_198 (see Fig. 11d). The local variational theory of elliptic LCSs targets material surfaces that locally maximize material shear over the finite time interval formula_103 of interest | https://en.wikipedia.org/wiki?curid=25077398 | 325,004 |
Gene set enrichment analysis GSEA uses complicated statistics, so it requires a computer program to run the calculations. GSEA has become standard practice, and there are many websites and downloadable programs that will provide the data sets and run the analysis. NASQAR (Nucleic Acid SeQuence Analysis Resource) is an open source, web-based platform for high-throughput sequencing data analysis and visualization. Users can perform GSEA using the popular R-based clusterProfiler package in a simple, user-friendly web app. NASQAR currently supports GO Term and KEGG Pathway enrichment with all organisms supported by an Org.Db database. The gene ontology (GO) annotation for 165 plant species and GO enrichment analysis is available. The Molecular Signatures Database hosts an extensive collection of annotated gene sets that can be used with most GSEA Software. The Broad Institute website is in cooperation with MSigDB and has a downloadable GSEA software, as well a general tutorial for those new to performing this analytical technique. WebGestalt is a web based gene set analysis toolkit. It supports three well-established and complementary methods for enrichment analysis, including Over-Representation Analysis (ORA), Gene Set Enrichment Analysis (GSEA), and Network Topology-based Analysis (NTA). Analysis can be performed against 12 organisms and 321,251 functional categories using 354 gene identifiers from various databases and technology platforms. Enrichr is a gene set enrichment analysis tool for mammalian gene sets | https://en.wikipedia.org/wiki?curid=43780204 | 159,289 |
Baxter International Baxter, unknown to the FDA, continued to use prison plasma in factor concentrate production until October 1983, despite having entered into an agreement with the FDA (11 months earlier) that they would no longer use US prison plasma, which posed a high risk of virus transmission. It was announced in quarter 1 of 1996 that Baxter had agreed to settle a lawsuit involving 200 Japanese haemophilia patients who had become infected with HIV as a result of using contaminated haemophilia products which were unheated. The Japanese courts ordered for each victim to receive $411,460 by March 29 that year. The Baxter Althane disaster in autumn 2001 was a series of 56 sudden deaths of kidney failure patients in Spain, Croatia, Italy, Germany, Taiwan, Colombia and the USA (mainly Nebraska and Texas). All had received hospital treatment with Althane hemodialysis equipment, a product range manufactured by Baxter International, USA. In 2008, the quality of blood thinning products produced by Baxter was brought into question when they were linked to 81 deaths and 785 severe allergic reactions in the United States according to the FDA. Upon inspection, one of the raw ingredients used by Baxter was found to be contaminated – between 5 and 20 percent – with a substance that was similar, but not identical, to the ingredient itself. The company initiated a voluntary recall, temporarily suspended the manufacture of heparin, and launched an investigation | https://en.wikipedia.org/wiki?curid=2432238 | 3,509 |
SME One Asia Awards In 2013, the third Awards Dinner was held at Marina Bay Sands, with a total of 1180 guests attending the event, the guests include the Winners and their guests, business owners, distinguished guests, ambassadors, foreign delegates, members from trade associations, government institutions, sponsors as well as partners, media partners and journalists from the various newspapers. Below is the summary of the number of awards given out for each year, including significant winners For the Dinner, Channel News Asia was the official media partner for the SME One Asia Awards. Other supporting media partners include The Business Times, The Straits Times and Lianhe Zaobao. Also included are the various write ups that were featured in other publications. The 2013 includes participants from Malaysia, Philippines, Indonesia, Cambodia, South Korea and China. Supporting regional partners and their media providers are also invited for the event. Supporting Organisation: Singapore Indian Chamber of Commerce and Industry (SICCI) Official Knowledge Management Partner: Singapore Institute of Management Official Design Partner: A.S. Louken Group Pte Ltd Official Trophy Co-Sponsor: Royal Selangor International Official Media Partner: CNBC | https://en.wikipedia.org/wiki?curid=42356699 | 496,401 |
Mujeeb R. Malik from the NASA/Langley Research Center, was awarded the status of Fellow in the American Physical Society, after he was nominated by their Division of Fluid Dynamics in 2008, for "pioneering contributions to the understanding of the breakdown of cross flow vortices in three-dimensional boundary layers, attachment-line and hypersonic boundary layer instability including real gas effects, and developing physics-based methods for the prediction of laminar-turbulent transition." | https://en.wikipedia.org/wiki?curid=53848857 | 8,794 |
Tannin The difficulty is that the establishing of a titer for tannin is not always convenient since it is extremely difficult to obtain the pure tannin. Neubauer proposed to remove this difficulty by establishing the titer not with regard to the tannin but with regard to crystallised oxalic acid, whereby he found that 83 g oxalic acid correspond to 41.20 g tannin. Löwenthal's method has been criticized. For instance, the amount of indigo used is not sufficient to retard noticeably the oxidation of the non-tannins substances. The results obtained by this method are therefore only comparative. A modified method, proposed in 1903 for the quantification of tannins in wine, Feldmann's method, is making use of calcium hypochlorite, instead of potassium permanganate, and indigo sulfate. Strawberries contain both hydrolyzable and condensed tannins. Most berries, such as cranberries, and blueberries, contain both hydrolyzable and condensed tannins. Nuts that can be consumed raw, such as hazelnuts, walnuts, and pecans, contain high amounts of tannins. Almonds have a lower content. concentration in the crude extract of these nuts did not directly translate to the same relationships for the condensed fraction. Cloves, tarragon, cumin, thyme, vanilla, and cinnamon all contain tannins. Most legumes contain tannins. Red-colored beans contain the most tannins, and white-colored beans have the least. Peanuts without shells have a very low tannin content. Chickpeas (garbanzo beans) have a smaller amount of tannins | https://en.wikipedia.org/wiki?curid=61983 | 184,870 |
Oakmont Country Club Both competitors had completed the 72 holes with a 283 (–1). It was the first professional victory for Nicklaus, and the first of his 18 professional majors. Palmer won the next major, the 1962 British Open, and his fourth Masters in 1964, but never another U.S. Open. In 1962, par was reduced by a stroke to 71 (the first hole became a par-4) and the course length was slightly reduced to ; the average score for the field was 75.86 (+ 4.86) and the field recorded 19 rounds under par. The purse was $81,600 and the champion earned $17,500 ($ and $ in dollars). Johnny Miller shot a final round 63 (–8) to set a record low score at a U.S. Open, and finished at 279 (–5) to win by one stroke in 1973. Following an overnight rainstorm, Miller entered the final round in 12th place at three-over, six strokes behind the four co-leaders. Miller had carded a disappointing five-over 76 on Saturday, and his tee time on Sunday was about an hour ahead of the final pairing, which included Arnold Palmer. Miller birdied the first four holes and hit all 18 greens in regulation, and used only 29 putts. Miller and four others were the only ones to break par during the final round in 1973. The par 71 course played at and the average score for the field was 75.45 (+ 4.45) and the field recorded 40 rounds under par. The purse was $219,400 and the champion earned $35,000 ($ and $ in dollars) | https://en.wikipedia.org/wiki?curid=2253465 | 340,010 |
Active Format Description As of 2006, AFDs are only broadcast in a minority of the countries using MPEG digital television but used most notably in the UK as required by the Digital TV Group D-Book. As a result, the quality of implementation in receivers is variable. Some receivers only respect the basic "active area" information. More fully featured receivers also support the "safe area" information, and will use this to optimise the display for the shape of the viewer's screen. Display in the compromise letterbox format was not supported by initial British receivers, which limited the value of the AFD flags - this ratio is especially useful when watching widescreen material on smaller 4:3 sets. The line 23 data format allows signaling of the source (coded image) aspect ratio and the Active Format Descriptor. A concerted effort on the part of US broadcasters to broadcast AFD began in 2008 in preparation for the US DTV transition which occurred on June 12, 2009. After the DTV transition, 4:3 versions of programming are not available directly from a large percentage of US broadcasters. Cable and satellite providers down-convert 16:9 HD feeds from these broadcasters to generate the 4:3 SD versions for their SD viewers. The most common forms of down-conversion are letterbox or center-cut (cropping off the left and right sides of the 16:9 image to fit into the 4:3 raster). Some US broadcasters transmit AFD with their HD DTV signals in order to maintain control over how SD viewers will receive their programming | https://en.wikipedia.org/wiki?curid=4666541 | 215,328 |
Estoppel " So, for instance, if A intentionally and falsely leads B to believe that certain land belongs to A, and thereby induces B to buy and pay for it, and only later does A acquire the land, then A is not allowed to argue to void the sale on the ground that, at the time of the sale, he had no title. The doctrine of estoppel is based on the principle that consistency in word and action imparts certainty and honesty to human affairs. If a person makes a representation to another, on the faith of which the latter acts, to his prejudice, the former cannot recant the representation. However, estoppel has no application to representations made regarding the fundamental rights conferred by the Constitution of India, the source of all laws, which exists not only to benefit individuals but to secure collective rights. Thus, no one can barter away the freedoms conferred upon him by the Constitution. A concession made by him in a proceeding, whether under a mistake of law or otherwise, that he does not possess or will not enforce any particular fundamental right, cannot estop him, as enforcing estoppel would defeat the purpose of the Constitution. | https://en.wikipedia.org/wiki?curid=221254 | 500,266 |
Tramadol acts as a serotonin-norephinephrine reuptake inhibitor and can interact with other serotonergic medications (selective serotonin reuptake inhibitors, serotonin–norepinephrine reuptake inhibitors, tricyclic antidepressants, triptans, cough and cold medications containing dextromethorphan, herbal products containing St. John’s wort, and medications that inhibit the metabolism of serotonin, such as monoamine oxidase inhibitors) and in combination may lead to serotonin syndrome. It may also make some serotonergic antagonist anti-emetic medications (ondansetron) less effective. also acts as an opioid agonist and can increase the risk for side effects when used with other opioid analgesics (such as morphine, pethidine, tapentadol, oxycodone, and fentanyl). is metabolized by CYP2D6 enzymes which contribute to the metabolism of approximately 25% of all medications. Any medications with the ability to inhibit or induce these enzymes may interact with tramadol. increases the risk for seizures by lowering the seizure threshold. Using other medications that lower seizure threshold (such as antipsychotic medications or amphetamines), further increases this risk. induces analgesic effects through a variety of different targets on the noradrenergic system, serotoninergic system and opioid receptors system. exists as a racemic mixture, the positive enantiomer inhibits serotonin reuptake while the negative enantiomer inhibits noradrenaline re-uptake, by binding to and blocking the transporters | https://en.wikipedia.org/wiki?curid=250858 | 25,678 |
Control (management) The objective of organizational control is to see that the specified function is achieved. The objective of operational control is to ensure that variations in daily output are maintained within prescribed limits. It is one thing to design a system that contains all of the elements of control, and quite another to make it operate true to the best objectives of design. Operating "in control" or "with plan" does not guarantee optimum performance. For example, the plan may not make the best use of the inputs of materials, energy, or information — in other words, the system may not be designed to operate efficiently. Some of the more typical problems relating to control include the difficulty of measurement, the problem of timing information flow, and the setting of proper standards. When objectives are not limited to quantitative output, the measurement of system effectiveness is difficult to make and subsequently perplexing to evaluate. Many of the characteristics pertaining to output do not lend themselves to quantitative measurement. This is true particularly when inputs of human energy cannot be related directly to output. The same situation applies to machines and other equipment associated with human involvement, when output is not in specific units. In evaluating man-machine or human-oriented systems, psychological and sociological factors obviously do not easily translate into quantifiable terms | https://en.wikipedia.org/wiki?curid=11523713 | 373,196 |
Information security ISO/IEC 20000, The Visible OPS Handbook: Implementing ITIL in 4 Practical and Auditable Steps (Full book summary), and Information Technology Infrastructure Library all provide valuable guidance on implementing an efficient and effective change management program information security. Business continuity management (BCM) concerns arrangements aiming to protect an organization's critical business functions from interruption due to incidents, or at least minimize the effects. BCM is essential to any organization to keep technology and business in line with current threats to the continuation of business as usual. The BCM should be included in an organizations risk analysis plan to ensure that all of the necessary business functions have what they need to keep going in the event of any type of threat to any business function. It encompasses: Whereas BCM takes a broad approach to minimizing disaster-related risks by reducing both the probability and the severity of incidents, a disaster recovery plan (DRP) focuses specifically on resuming business operations as quickly as possible after a disaster. A disaster recovery plan, invoked soon after a disaster occurs, lays out the steps necessary to recover critical information and communications technology (ICT) infrastructure | https://en.wikipedia.org/wiki?curid=15036 | 135,753 |
Acoustic metamaterial Here a method is shown which can be applied to two-dimensional stop band and bandgap control with either photonic or sonic structures. Similar to photonic and electromagnetic metamaterial fabrication, a sonic metamaterial is embedded with localized sources of mass density "ρ" and the (elastic) bulk modulus β parameters, which are analogous to permittivity and permeability, respectively. The sonic (or phononic) metamaterials are sonic crystals, as in the previous section. These crystals have a solid lead core and a softer, more elastic silicone coating. The sonic crystals had built-in localized resonances due to the coated spheres which resulted in almost flat dispersion curves. Low-frequency bandgaps and localized wave interactions of the coated spheres were analyzed and presented in. This method can be used to tune bandgaps inherent in the material and, also, create new low-frequency bandgaps. It is also applicable for designing low-frequency phononic crystal waveguides (radio frequency). Doubly periodic square array of SRRs are used to illustrate the methodology. Phononic crystals are synthetic materials that are formed by periodic variation of the acoustic properties of the material (i.e., elasticity and mass). One of the main properties of the phononic crystals is the possibility of having a phononic bandgap. A phononic crystal with phononic bandgap prevents phonons of selected ranges of frequencies from being transmitted through the material | https://en.wikipedia.org/wiki?curid=24476128 | 31,133 |
Via (electronics) A via consists of: A via may be at the edge of the board so that it is cut in half when the board is separated; this is known as a castellated hole and is used for a variety of reasons, including allowing one PCB to be soldered to another in a stack. Three major kinds of vias are shown in right figure. The basic steps of making a PCB are: making the substrate material and stacking it in layers; through-drilling of plating the vias; and copper trace patterning using photolithography and etching. With this standard procedure, possible via configurations are limited to through-holes. Depth-controlled drilling techniques such as using lasers can allow for more varied via types. PCB manufacturing typically starts with a so-called core, a basic double-sided PCB. Layers beyond the first two are stacked from this basic building block. If two more layers are consecutively stacked from bottom of core, you can have a 1-2 via, a 1-3 via and a through hole. Each type of via is made by drilling at each stacking stage. If one layer is stacked on top of the core and other is stacked from the bottom, the possible via configurations are 1-3, 2-3 and through hole. The user must gather information about the PCB manufacturer's allowed methods of stacking and possible vias. For cheaper boards, only through holes are made and antipad (or clearance) is placed on layers which are supposed not to be contacted to vias | https://en.wikipedia.org/wiki?curid=2681475 | 373,997 |
Statistical potential The total free energy difference of a protein, formula_23, is then claimed to be the sum of all the pairwise free energies: where the sum runs over all amino acid pairs formula_25 (with formula_26) and formula_27 is their corresponding distance. In many studies formula_12 does not depend on the amino acid sequence. Intuitively, it is clear that a low value for formula_23 indicates that the set of distances in a structure is more likely in proteins than in the reference state. However, the physical meaning of these PMFs have been widely disputed since their introduction. The main issues are the interpretation of this "potential" as a true, physically valid potential of mean force, the nature of the reference state and its optimal formulation, and the validity of generalizations beyond pairwise distances. The first, qualitative justification of PMFs is due to Sippl, and based on an analogy with the statistical physics of liquids. For liquids, the potential of mean force is related to the radial distribution function formula_30, which is given by: where formula_10 and formula_18 are the respective probabilities of finding two particles at a distance formula_3 from each other in the liquid and in the reference state. For liquids, the reference state is clearly defined; it corresponds to the ideal gas, consisting of non-interacting particles | https://en.wikipedia.org/wiki?curid=7297179 | 161,966 |
Peruća Lake The maximum reservoir flood level is 362.00 m.a.s.l. This was considered a great achievement at that time. The majority of the catchment drains calcareous are rocks of the Cretaceous period, predominantly limestone. Peruća lake is the third largest lake in Croatia by size. It is spread over 10–20 km², and is 60–70 m at its maximum depth, depending on quantity of rain/snow in winter. Building the dam on the Cetina and creating the lake, has limited flooding downstream. Dalmatia has secured a greater energy supply. Before it was built, the State of SFRY nationalised land which belonged to the inhabitants of the neighbouring settlements of Vrlika, Garjak, Kosore, Ježević, Laktac, Dabar, , Zasiok, Bitelić, Rumin, Hrvace, Satrić, Potravlje, Maljkovo, Otišić and Maovice. In the middle of the lake, there was an old Orthodox Dragović Monastery. Before the artificial lake for the hydroelectric power station at Peruća was created, the Dragović monastery was moved to a hill not far from the old fortress at Gradina. The Peruća Dam was gravely damaged during the Croatian War of Independence, when on January 28, 1993, in the aftermath of Operation Maslenica, at 10:48 a.m., the dam was blown up in an intentional effort to destroy it by Serbian/Yugoslav army forces. They mined it with 30 tons of explosive and detonated the charges with the intention of harming thousands of Croatian civilians downstream. The explosion caused heavy damage, but ultimately failed to demolish the dam | https://en.wikipedia.org/wiki?curid=21566237 | 349,063 |
Health technology assessment Also in the UK, the Multidisciplinary Assessment of Technology Centre for Healthcare carries out HTA in collaboration with the health service, the NHS and various industrial partners. MATCH is organised into four themes addressing key HTA topics including Health Economics, Tools for Industry, User Needs and Procurement and Supply chain. Canada also has a health technology assessment body called the Canadian Agency for Drugs and Technologies in Health (CADTH) | https://en.wikipedia.org/wiki?curid=22406877 | 266,689 |
Alewife (multiprocessor) Alewife was a cache coherent multiprocessor developed in the early 1990s by a group led by Anant Agarwal at the Massachusetts Institute of Technology. It was based on a network of up to 512 processing nodes, each of which used the Sparcle computer architecture, which was formed by modifying a Sun Microsystems SPARC CPU to include the APRIL techniques for fast context switches. The Alewife project was one of two predecessors cited by the creators of the popular Beowulf cluster multiprocessor. | https://en.wikipedia.org/wiki?curid=15484221 | 132,474 |
Temporin Temporins are a family of peptides isolated originally from the skin secretion of the European red frog, "Rana temporaria". Peptides belonging to the temporin family have been isolated also from closely related North American frogs. In elephants, temporin is secreted by temporal glands during the period of musth. It contains proteins, lipids (notably cholesterol), phenols, cresols and sesquiterpenes (notably farnesol and its derivatives). This is not related to temporins that are antimicrobial peptides In old Sanskrit texts, it is referred to as rut fluid (, or ) and is considered to be a symbol of potency and vigour: However, from the point of view of ancient Indian elephant science (), temporin is not a direct symptom of rut. This is not related to temporins that are antimicrobial peptides | https://en.wikipedia.org/wiki?curid=31828910 | 166,856 |
Kari-Finn Oy is a Finnish family-owned company. It is a subsidiary company of KFR Hollola Oy. The main product of the company is multilevel float switch, a cable-suspended control device which tilts as the liquid level rises or falls. Oy announces that based on its own market research, Kari float switch is the only product on the market that makes possible many functions with just one switch. This product was invented by the founder of the company, an inventor and an engineer, Mauno Kari. Besides the main product, Oy produces also many other electrical devices, such as electrode switches based on conductiveness of liquid, silo switches made for surface level control for loose storage items, temperature based thermal fuses, watertight pump cable connectors and alarm and control units for pumping stations. In year 2008 the company manufactured over 50.000 float switches. Oy was established in 1965. At first the company name was T:mi Mauno Kari, later Ky. Ky began to make itself the plastic parts it needed for the float switches. And as there was capacity left, it also began to produce plastic parts for other industrial companies in Lahti region. Ky was divided into two companies in 1988: Oy making float switches and its subsidiary company Muovisto Oy making plastic parts. In year 2008 a new parent company, KFR Hollola Oy, was founded. It started to take care of corporations lead services, management, financing actions and research and development services | https://en.wikipedia.org/wiki?curid=25790276 | 378,073 |
History of photography Henry Fox Talbot had already succeeded in creating stabilized photographic negatives on paper in 1835, but worked on perfecting his own process after reading early reports of Daguerre's invention. In early 1839, he acquired a key improvement, an effective fixer, from his friend John Herschel, a polymath scientist who had previously shown that hyposulfite of soda (commonly called "hypo" and now known formally as sodium thiosulfate) would dissolve silver salts. News of this solvent also benefited Daguerre, who soon adopted it as a more efficient alternative to his original hot salt water method. Talbot's early silver chloride "sensitive paper" experiments required camera exposures of an hour or more. In 1841, Talbot invented the calotype process, which, like Daguerre's process, used the principle of chemical development of a faint or invisible "latent" image to reduce the exposure time to a few minutes. Paper with a coating of silver iodide was exposed in the camera and developed into a translucent negative image. Unlike a daguerreotype, which could only be copied by rephotographing it with a camera, a calotype negative could be used to make a large number of positive prints by simple contact printing. The calotype had yet another distinction compared to other early photographic processes, in that the finished product lacked fine clarity due to its translucent paper negative. This was seen as a positive attribute for portraits because it softened the appearance of the human face | https://en.wikipedia.org/wiki?curid=2435889 | 302,200 |
Classical XY model The classical XY model (sometimes also called classical rotor (rotator) model or O(2) model) is a lattice model of statistical mechanics. It is the special case of the "n"-vector model for . Given a -dimensional lattice , per each lattice site there is a two-dimensional, unit-length vector The spin configuration, is an assignment of the angle for each . Given a "translation-invariant" interaction and a point dependent external field formula_1, the configuration energy is The case in which except for nearest neighbor is called "nearest neighbor" case. The configuration probability is given by the Boltzmann distribution with inverse temperature : where is the normalization, or partition function. The notation formula_4 indicates the expectation of the random variable in the infinite volume limit, after "periodic boundary conditions" have been imposed. The fact that at high temperature correlations decay exponentially fast, while at low temperatures decay with power law, even though in both regimes , is called Kosterlitz–Thouless transition. The continuous version of the XY model is often used to model systems that possess order parameters with the same kinds of symmetry, e.g. superfluid helium, hexatic liquid crystals. This is what makes them peculiar from other phase transitions which are always accompanied with a symmetry breaking. Topological defects in the XY model lead to a vortex-unbinding transition from the low-temperature phase to the high-temperature disordered phase | https://en.wikipedia.org/wiki?curid=954006 | 5,901 |
Logic level In digital circuits, a logic level is one of a finite number of states that a digital signal can inhabit. Logic levels are usually represented by the voltage difference between the signal and ground, although other standards exist. The range of voltage levels that represent each state depends on the logic family being used. In binary logic the two levels are logical high and logical low, which generally correspond to binary numbers 1 and 0 respectively. Signals with one of these two levels can be used in boolean algebra for digital circuit design or analysis. The use of either the higher or the lower voltage level to represent either logic state is arbitrary. The two options are active high and active low. Active-high and active-low states can be mixed at will: for example, a read only memory integrated circuit may have a chip-select signal that is active-low, but the data and address bits are conventionally active-high. Occasionally a logic design is simplified by inverting the choice of active level (see De Morgan's laws). The name of an active-low signal is historically written with a bar above it to distinguish it from an active-high signal. For example, the name Q, read "Q bar" or "Q not", represents an active-low signal. The conventions commonly used are: Many control signals in electronics are active-low signals (usually reset lines, chip-select lines and so on). Logic families such as TTL can sink more current than they can source, so fanout and noise immunity increase | https://en.wikipedia.org/wiki?curid=5652077 | 386,034 |
Wellsite information transfer standard markup language Energistics has custody of the standards and hosts the SIG. Energistics makes these and other industry standards available for use by all industry companies through a licensing agreement that is free of any fees or charges. WITSML Standards are defined using the W3C Internet standards for XML (notably XML Schema) and Web Services (including SOAP and WSDL)). The WITSML Standards define Web Services that define client/server interactions, known as the WITSML Application Programming Interface specifications. The WITSML Standards define more than 20 industry domain specific XML data object schemas to support drilling, completions, and intervention business functions. Download current standards WITSML Version 1.3.1 was released in March 2006. This was superseded by Version 1.3.1.1(bugfix), release in March 2007. WITSML Version 1.4.1 was released in September 2011. WITSML Version 2.0 was released in February 2017. WITS was a precursor of WITSML based on serial data exchange on a "Point to Point" basis, developed in the early 1980s (SPE Paper 16141) and was transferred to the American Petroleum Institute as a standard. However the rapid evolution of network technology, and the richness of data from LWD and rig data systems, drove BP and Statoil to explore a change to the standard. The initial project in 2000, DART ( Drilling Automation Real Time) was a CORBA approach, but this was dropped in favour of an XML based approach, that became WitsML. BP and Statoil passed custody of the new standard to Energistics in 2003 | https://en.wikipedia.org/wiki?curid=3174917 | 483,156 |
Comparative advantage If both countries specialize in the good for which they have a comparative advantage then trade, the terms of trade for a good (that benefit both entities) will fall between each entities opportunity costs. In the example above one unit of cloth would trade for between formula_24 units of wine and formula_25 units of wine. In 1930 Gottfried Haberler detached the doctrine of comparative advantage from Ricardo's labor theory of value and provided a modern opportunity-cost formulation. Haberler's reformulation of comparative advantage revolutionized the theory of international trade and laid the conceptual groundwork of modern trade theories. Haberler's innovation was to reformulate the theory of comparative advantage such that the value of good X is measured in terms of the forgone units of production of good Y rather than the labor units necessary to produce good X, as in the Ricardian formulation. Haberler implemented this opportunity-cost formulation of comparative advantage by introducing the concept of a production possibility curve into international trade theory. Since 1817, economists have attempted to generalize the Ricardian model and derive the principle of comparative advantage in broader settings, most notably in the neoclassical "specific factors" Ricardo-Viner (which allows for the model to include more factors than just labour) and "factor proportions" Heckscher–Ohlin models | https://en.wikipedia.org/wiki?curid=62018 | 509,954 |
Teal organisation A number of notable organisations around the world have adopted and operate with the model including The Morning Star Company (food processing, United States), Patagonia (apparel, United States), Sounds True (media, United States), AES (energy sector, international), Buurtzorg Nederland (health care, Netherlands), ESBZ (K–12 school, Germany), Heiligenfeld (mental health hospitals, Germany), Nucor (steel manufacturing, international), Varkey Foundation (non-profit organisation with expertisse in Education), Thomsen Trampedach (brand protection, Denmark). | https://en.wikipedia.org/wiki?curid=56830751 | 505,324 |
Elastic recoil detection Incorporating an absorber into the experimental set up can be the most difficult to achieve. The stopping of the beam using either direct or scattered methods can only be accomplished without also stopping the light impurity atoms, if it is heavier (beam ions) than the impurity atoms being analyzed. There are advantages when using absorber films: The major criterion for absorber foils used in ERDA is whether a recoiling impurity atom can be transmitted through the absorber, preferably a commercially available metal foil, while stopping heavy particles. Since the lighter atoms leave the absorber with smaller energies, the kinematic calculations do not provide much help. Favorable results have been obtained by using heavier ion beams of approximately 1 MeV/ nucleon. The best overall candidate is the Cl ion beam; although, Br would give better sensitivity by one order of magnitude compared to the Cl ion beam. The mass resolution, of the detector at "θ= 0°", of thin samples is "ΔM/Δx" ~ 0.3 amu/1000 Angstroms of the profile width. With thick samples, the mass resolution is feasible at θ≤30°. In thicker samples there is some degradation of mass resolution and slight loss of sensitivity. The detector solid angle has to be closed, but the thick sample can take more current without heating, which decreases sample degradation. Once the ion beam has ionized target sample atoms, the sample ions are recoiled toward the detector. The beam ions are scattered at an angle that does not permit them to reach the detector | https://en.wikipedia.org/wiki?curid=2321375 | 29,022 |
Real-estate lock box A real-estate lock box is a padlock-shaped box that generally hangs around the doorknob of a house that is on the market. The device holds the keys to a house to allow communal access for all real estate agents, while continuing to keep them secure. Permission is generally required from the seller, who is the owner, to install such a device on the door. Lock boxes can also be used for the general storage and security of keys for the use of familial access. Traditional real estate lock boxes are secured either with a manual key, a security code, or a swipe card, while newer versions operate in tandem with mobile devices, incorporating logging and remote control and configuration. New technology allows for computer generated codes to access the keys from a lockbox. When a buyers agent requests to see a property, a computer program will send a one time use code to the agent for a one time entry. This advancement allows for maximum security, and is nearly the equivalent to changing the lock every time a customer leaves. Other locks use applications to grant access upon arrival of the customer. | https://en.wikipedia.org/wiki?curid=31148530 | 286,029 |
Albertype An is a picture printed from a type of gelatine-coated plate produced by means of a photographic negative. The process was invented by Josef Albert, a German photographer who owned and directed a studio and photo lab in Augsburg. The technique is similar to collotype, but substitutes the gel plate for the lithographic stone used in collotype. Heliotype, invented in 1871 by Edwards, is another similar process. Albert's innovation was to replace the copper or stone with glass, construct a mechanical press, and cover it with another gel layer, silicate mixed with gelatin, in order to produce about two thousand prints from each plate using etching presses and hand rollers. This new process was presented at the 1868 Photographic Exhibition in Hamburg and “albertype,” was the name given by Joseph Albert. This technique was adopted by publishers creating thousands of postcards and viewbooks. In 1890 Adolph and Herman L. Wittemann founded the The Company, a postcard and viewbook publishing company. This company began to use what were then "new technologies" such as the albertype to reproduce photo-mechanical images. At that time they were able to collect negatives from the cities and towns of the United States and came to create more than 25,000 prints from 1890 to 1952. | https://en.wikipedia.org/wiki?curid=53511913 | 256,545 |
Fourth market trading is direct institution-to-institution trading without using the service of broker-dealers, thus avoiding both commissions, and the bid-ask spread. Trades are usually done in blocks. It is impossible to estimate the volume of fourth market activity because trades are not subject to reporting requirements. Studies have suggested that several million shares are traded per day. | https://en.wikipedia.org/wiki?curid=22720493 | 510,103 |
Multiple-criteria decision analysis Alternatively, if different criteria are combined by a weighted linear function, it is also possible to represent the problem in the weight space. Below are the demonstrations of the criterion and weight spaces as well as some formal definitions. Let us assume that we evaluate solutions in a specific problem situation using several criteria. Let us further assume that more is better in each criterion. Then, among all possible solutions, we are ideally interested in those solutions that perform well in all considered criteria. However, it is unlikely to have a single solution that performs well in all considered criteria. Typically, some solutions perform well in some criteria and some perform well in others. Finding a way of trading off between criteria is one of the main endeavors in the MCDM literature. Mathematically, the MCDM problem corresponding to the above arguments can be represented as where is the vector of "k" criterion functions (objective functions) and is the feasible set, . If is defined explicitly (by a set of alternatives), the resulting problem is called a multiple-criteria evaluation problem. If is defined implicitly (by a set of constraints), the resulting problem is called a multiple-criteria design problem. The quotation marks are used to indicate that the maximization of a vector is not a well-defined mathematical operation | https://en.wikipedia.org/wiki?curid=1050551 | 119,075 |
Murray Rothbard Rothbard also suggested that opposition to King, whom he demeaned as a "coercive integrationist", should be a litmus test for members of his "paleolibertarian" political movement. Political scientist Jean Hardisty noted that Rothbard endorsed the argument of Richard Herrnstein and Charles Murray's book "The Bell Curve", that the achievement gap in academic performance between black and white Americans can be attributed to the genetic inferiority of blacks. Like Randolph Bourne, Rothbard believed that "war is the health of the state". According to David Gordon, this was the reason for Rothbard's opposition to aggressive foreign policy. Rothbard believed that stopping new wars was necessary and that knowledge of how government had led citizens into earlier wars was important. Two essays expanded on these views "War, Peace, and the State" and "The Anatomy of the State". Rothbard used insights of Vilfredo Pareto, Gaetano Mosca and Robert Michels to build a model of state personnel, goals and ideology. In an obituary for his friend historical revisionist Harry Elmer Barnes, Rothbard wrote: Rothbard's colleague Joseph Stromberg notes that Rothbard made two exceptions to his general condemnation of war: "the American Revolution and the War for Southern Independence, as viewed from the Confederate side" | https://en.wikipedia.org/wiki?curid=20217 | 516,307 |
DDC-I Success of the Ada project led to a separate company being formed in 1985, called DDC International A/S, with the purpose of commercializing the Ada compiler system product. Like its originator, it was based in Lyngby, Denmark. Ole N. Oest was named the managing director of DDC International. In 1986, DDC-I, Inc. was founded as the American subsidiary company. Located in Phoenix, Arizona, it focused on sales, customer support, and engineering consulting activities in the United States. established a business in selling the Ada compiler system product, named DACS, directly to firms, both as software to develop projects in Ada with, and as source code to computer makers and others, who would rehost or retarget it to other processors and operating systems. The first business sold both native compilers and cross compilers, with the latter more common since Ada was primarily used in the embedded systems realm. One of the first cross compilers that developed was from VAX/VMS to the Intel 8086 and Intel 80286; the effort was already underway by early 1985. It began as a joint venture with the Italian defense electronics company Selenia that would target both their MARA-860 and MARA-286 multi-microprocessor computers, based on the 8086 and 80286 architectures, and generic embedded and OS-hosting 8086 and 80286 systems. This work was the start of what would become the largest-selling product line for the firm. developed a reputation for quality Ada cross compilers and runtime systems for Intel 80x86 processors | https://en.wikipedia.org/wiki?curid=28542189 | 133,404 |
Photoelasticity Birefringence is a phenomenon in which a ray of light passing through a given material experiences two refractive indices. The property of birefringence (or double refraction) is observed in many optical crystals. Upon the application of stresses, photoelastic materials exhibit the property of birefringence, and the magnitude of the refractive indices at each point in the material is directly related to the state of stresses at that point. Information such as maximum shear stress and its orientation are available by analyzing the birefringence with an instrument called a polariscope. When a ray of light passes through a photoelastic material, its electromagnetic wave components are resolved along the two principal stress directions and each component experiences a different refractive index due to the birefringence. The difference in the refractive indices leads to a relative phase retardation between the two components. Assuming a thin specimen made of isotropic materials, where two-dimensional photoelasticity is applicable, the magnitude of the relative retardation is given by the "stress-optic law": where Δ is the induced retardation, "C" is the stress-optic coefficient, "t" is the specimen thickness, "λ" is the vacuum wavelength, and σ and σ are the first and second principal stresses, respectively. The retardation changes the polarization of transmitted light. The polariscope combines the different polarization states of light waves before and after passing the specimen | https://en.wikipedia.org/wiki?curid=1533196 | 211,950 |
History of laptops The computer company was a failure and did not last for very long. Although it was large and heavy compared to today's laptops, with a tiny 5" CRT monitor, it had a near-revolutionary impact on business, as professionals were able to take their computer and data with them for the first time. This and other "luggables" were inspired by what was probably the first portable computer, the Xerox NoteTaker. The Osborne was about the size of a portable sewing machine, and could be carried on commercial aircraft. The Osborne 1 weighed close to 11 kg and was priced at $1795. The Compaq Portable was the first PC-compatible portable computer created in 1982. The first shipment was in March 1983 and was priced at $2,995. The Compaq Portable folded up into a luggable case the size of a portable sewing machine, similar in size to the Osbourne 1. The third model of this development, Compaq Portable II, featured high resolution graphics on its tube display. It was the first portable computer ready to be used on the shop floor, and for CAD and diagram display. It established Compaq as a major brand on the market. The first significant development towards laptop computing was announced in 1981 and sold from July 1982, the 8/16-bit Epson HX-20. It featured a full-transit 68-key keyboard, rechargeable nickel-cadmium batteries, a small (120×32-pixel) dot-matrix LCD with 4 lines of text, 20 characters per line text mode, a 24 column dot matrix printer, a Microsoft BASIC interpreter, and 16 KB of RAM (expandable to 32 KB) | https://en.wikipedia.org/wiki?curid=16785037 | 111,975 |
Robot This allows a single modular robot the ability to be fully specialized in a single task, as well as the capacity to be specialized to perform multiple different tasks. Modular robotic technology is currently being applied in hybrid transportation, industrial automation, duct cleaning and handling. Many research centres and universities have also studied this technology, and have developed prototypes. A "collaborative robot" or "cobot" is a robot that can safely and effectively interact with human workers while performing simple industrial tasks. However, end-effectors and other environmental conditions may create hazards, and as such risk assessments should be done before using any industrial motion-control application. The collaborative robots most widely used in industries today are manufactured by Universal Robots in Denmark. Rethink Robotics—founded by Rodney Brooks, previously with iRobot—introduced Baxter in September 2012; as an industrial robot designed to safely interact with neighboring human workers, and be programmable for performing simple tasks. Baxters stop if they detect a human in the way of their robotic arms and have prominent off switches. Intended for sale to small businesses, they are promoted as the robotic analogue of the personal computer. , 190 companies in the US have bought Baxters and they are being used commercially in the UK. Roughly half of all the robots in the world are in Asia, 32% in Europe, and 16% in North America, 1% in Australasia and 1% in Africa | https://en.wikipedia.org/wiki?curid=25781 | 434,671 |
Adsorption The same group applied the model to CO hydrogenation (Fischer–Tropsch synthesis). Zupanc "et al." (2002) subsequently confirmed the same model for hydrogen adsorption on magnesia-supported caesium-ruthenium bimetallic catalysts. Trens "et al." (2009) have similarly described CO surface diffusion on carbon-supported Pt particles of varying morphology. In the case catalytic or adsorbent systems where a metal species is dispersed upon a support (or carrier) material (often quasi-inert oxides, such as alumina or silica), it is possible for an adsorptive species to indirectly adsorb to the support surface under conditions where such adsorption is thermodynamically unfavorable. The presence of the metal serves as a lower-energy pathway for gaseous species to first adsorb to the metal and then diffuse on the support surface. This is possible because the adsorbed species attains a lower energy state once it has adsorbed to the metal, thus lowering the activation barrier between the gas phase species and the support-adsorbed species. Hydrogen spillover is the most common example of an adsorptive spillover. In the case of hydrogen, adsorption is most often accompanied with dissociation of molecular hydrogen (H) to atomic hydrogen (H), followed by spillover of the hydrogen atoms present. The spillover effect has been used to explain many observations in heterogeneous catalysis and adsorption | https://en.wikipedia.org/wiki?curid=207601 | 366,988 |
Video tape recorder However, imperfection being inevitable, the timing of the playback always differs to some extent from the original signal. Longitudinal error (error arising from effects in the long direction of the tape) can be caused by variations in the rotational rate of the capstan drive, stretching of the tape medium, and jamming of tape in the machine. Transverse error (error arising from effects in the cross-tape direction) can be caused by variations in the rotational speed of the scanning drum and differences in the angle between the tape and the scanning heads (usually addressed by video tracking controls). Longitudinal errors are similar to the ones that cause wow and flutter in audio recordings. Since these errors are not so subtle and since it is standard video recording practice to record a parallel control track, these errors are detected and servos are adjusted accordingly to dramatically reduce this problem. Many of the deficiencies of the open-reel systems were overcome with the invention of the videocassette recorder (VCR), where the videotape is enclosed in a user-friendly videocassette shell. This subsequently became the most familiar type of VTR known to consumers. In this system, the tape is preattached onto two reels enclosed within the cassette, and tape loading and unloading is automated. There is no need for the user to ever touch the tape, and the media can be protected from dust, dirt, and tape misalignments that can foul the recording mechanism | https://en.wikipedia.org/wiki?curid=373862 | 246,258 |
Boston Common Tablet is a 1913 sculpture by R. Clipston Sturgis, installed at Boston Common in Boston, Massachusetts, United States. The slate and granite tablet is installed near the intersection of Park and Tremont streets, and measures approximately 15 x 5 x 20 ft. An inscription reads: . The artwork was surveyed as part of the Smithsonian Institution's "Save Outdoor Sculpture!" program in 1997. | https://en.wikipedia.org/wiki?curid=62115586 | 351,449 |
Glycoside In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme hydrolysis, which causes the sugar part to be broken off, making the chemical available for use. Many such plant glycosides are used as medications. Several species of "Heliconius" butterfly are capable of incorporating these plant compounds as a form of chemical defense against predators. In animals and humans, poisons are often bound to sugar molecules as part of their elimination from the body. In formal terms, a glycoside is any molecule in which a sugar group is bonded through its anomeric carbon to another group via a glycosidic bond. Glycosides can be linked by an O- (an "O-glycoside"), N- (a "glycosylamine"), S-(a "thioglycoside"), or C- (a "C-glycoside") glycosidic bond. According to the IUPAC, the name ""C"-glycoside" is a misnomer; the preferred term is ""C"-glycosyl compound". The given definition is the one used by IUPAC, which recommends the Haworth projection to correctly assign stereochemical configurations. Many authors require in addition that the sugar be bonded to a "non-sugar" for the molecule to qualify as a glycoside, thus excluding polysaccharides. The sugar group is then known as the "glycone" and the non-sugar group as the "aglycone" or "genin" part of the glycoside | https://en.wikipedia.org/wiki?curid=518902 | 34,432 |
Dynamic mechanical analysis Extension of formula_29 with trigonometric identity formula_30 lead to Comparison of the two formula_32 equations lead to the definition of formula_11 and formula_12. One important application of DMA is measurement of the glass transition temperature of polymers. Amorphous polymers have different glass transition temperatures, above which the material will have rubbery properties instead of glassy behavior and the stiffness of the material will drop dramatically with an increase in viscosity. At the glass transition, the storage modulus decreases dramatically and the loss modulus reaches a maximum. Temperature-sweeping DMA is often used to characterize the glass transition temperature of a material. Varying the composition of monomers and cross-linking can add or change the functionality of a polymer that can alter the results obtained from DMA. An example of such changes can be seen by blending ethylene-propylene-diene monomer (EPDM) with styrene-butadiene rubber (SBR) and different cross-linking or curing systems. Nair "et al." abbreviate blends as ES, ES, etc., where ES equals the weight percent of EPDM in the blend and S denotes sulfur as the curing agent. Increasing the amount of SBR in the blend decreased the storage modulus due to intermolecular and intramolecular interactions that can alter the physical state of the polymer. Within the glassy region, EPDM shows the highest storage modulus due to stronger intermolecular interactions (SBR has more steric hindrance that makes it less crystalline) | https://en.wikipedia.org/wiki?curid=258827 | 35,479 |
Liquefied natural gas terminal is a structure for liquefied natural gas to store. It can comprise special tanks, ships or even building structures. Port infrastructures and pipelines are also a part of LNG terminals. Liquefied natural gas is the form used to transport natural gas over long distances, often by sea. In most cases, LNG terminals are purpose-built ports used exclusively to export or import LNG. Liquefied natural gas terminals can be divided into two types: liquefaction terminals (export) and or receiving terminals (import). A floating storage and regasification unit, or FSRU for short, is an LNG terminal whose main structure is a special ship that is moored next to the port. As of January 2014 there are operating FSRUs in Brazil, Argentina, Kuwait, Israel, the UAE, Italy, Indonesia, China and Lithuania. | https://en.wikipedia.org/wiki?curid=41843579 | 504,024 |
Isotopes of iron The isotope Fe is widely used in Mössbauer spectroscopy and the related nuclear resonance vibrational spectroscopy due to the low natural variation in energy of the 14.4 keV nuclear transition. The transition was famously used to make the first definitive measurement of gravitational redshift, in the 1960 Pound-Rebka experiment. Iron-60 is an iron isotope with a half-life of 2.6 million years, but was thought until 2009 to have a half-life of 1.5 million years. It undergoes beta decay to cobalt-60, which then decays with a half-life of about 5 years to stable nickel-60. Traces of iron-60 have been found in lunar samples. In phases of the meteorites "Semarkona" and "Chervony Kut", a correlation between the concentration of Ni, the granddaughter isotope of Fe, and the abundance of the stable iron isotopes could be found, which is evidence for the existence of Fe at the time of formation of the solar system. Possibly the energy released by the decay of Fe contributed, together with the energy released by decay of the radionuclide Al, to the remelting and differentiation of asteroids after their formation 4.6 billion years ago. The abundance of Ni present in extraterrestrial material may also provide further insight into the origin of the solar system and its early history. Iron-60 found in fossilised bacteria in sea floor sediments suggest there was a supernova in the vicinity of the solar system approximately 2 million years ago. Iron-60 is also found in sediments from 8 million years ago | https://en.wikipedia.org/wiki?curid=2527048 | 27,445 |
Hopanoids are a diverse subclass of triterpenoids with the same hydrocarbon skeleton as the compound hopane. This group of pentacyclic molecules therefore refers to simple hopenes, hopanols and hopanes, but also to extensively functionalized derivatives such as bacteriohopanepolyols (BHP) and hopanoids covalently attached to lipid A. The first known hopanoid, hydroxyhopanone, was isolated by two chemists at The National Gallery, London working on the chemistry of dammar gum, a natural resin used as a varnish for paintings. The name hopane was derived from the genus Hopea (a source of the resin), which in turn was named after the botanist John Hope. Since this first finding in an angiosperm, however, hopanoids have been found in membranes of bacteria, lichens, bryophytes, ferns and fungi. Because of their geostable structures, various hopanoids are preserved in petroleum reservoirs, rocks and sediment, allowing them to be used as biological markers. have not been detected in archaea. About 10% of sequenced bacterial genomes have a putative "shc" gene encoding a squalene-hopene cyclase and can presumably make hopanoids, which have been shown to play diverse roles in the plasma membrane and may allow some organisms to adapt in extreme environments. Since hopanoids modify plasma membrane properties in bacteria, they are frequently compared to sterols, such as cholesterol, which modulate membrane fluidity and serve other functions in eukaryotes | https://en.wikipedia.org/wiki?curid=2313403 | 168,716 |
Isotopic labeling Ra has a half-life of 11 days and can occur naturally at specific locations in rivers and groundwater sources. The isotopic ratio of radium will then decrease as the water from the source river enters a bay or estuary. By measuring the amount of Ra at a number of different locations, a circulation pattern can be deciphered. This same exact process can also be used to study the movement and discharge of groundwater. Various isotopes of lead can be used to study circulation on a global scale. Different oceans (i.e. the Atlantic, Pacific, Indian, etc.) have different isotopic signatures. This results from differences in isotopic ratios of sediments and rocks within the different oceans. Because the different isotopes of lead have half-lives of 50–200 years, there is not enough time for the isotopic ratios to be homogenized throughout the whole ocean. Therefore, precise analysis of Pb isotopic ratios can be used to study the circulation of the different oceans. Isotopes with extremely long half-lives can be used to study multi-million year processes, such as tectonics and extreme climate change. The isotopic ratio of strontium (half-life ~2 Ma) can be analyzed within ice cores to examine changes over the earth's lifetime. Differences in this ratio within the ice core would indicate significant alterations in the earth's geochemistry. The aforementioned processes can be measured using naturally occurring isotopes. Nevertheless, anthropogenic isotopes are also extremely useful for oceanographic measurements | https://en.wikipedia.org/wiki?curid=1652307 | 85,495 |
Seismic risk refers to the risk of damage from earthquake to a building, system, or other entity. has been defined, for most management purposes, as the potential economic, social and environmental consequences of hazardous events that may occur in a specified period of time. A building located in a region of high seismic hazard is at lower risk if it is built to sound seismic engineering principles. On the other hand, a building located in a region with a history of minor seismicity, in a brick building located on fill subject to liquifaction can be as high or higher risk. A special subset is urban seismic risk which looks at the specific issues of cities. Risk determination and emergency response can also be determined through the use of an Earthquake scenario. The determination of seismic risk is the foundation for risk mitigation decision-making, a key step in risk management. Large corporations and other enterprises (e.g., local governments) analyze their 'portfolio' of properties, to determine how to best allocate limited funds for structural strengthening of buildings, or other risk reduction measures such as emergency planning. In calculating the risk of each facility in the 'portfolio', potential life safety and economic losses due not only to structural damage, but also to equipment, contents and business interruption are considered. Public agencies (local, state governments and federal agencies) similarly analyze their portfolios | https://en.wikipedia.org/wiki?curid=230530 | 367,323 |
Triple bottom line A number of respected reporting institutes and registries exist including the Global Reporting Initiative, CERES, Institute 4 Sustainability and others. The ecological bottom line is akin to the concept of eco-capitalism. The profit or economic bottom line deals with the economic value created by the organization after deducting the cost of all inputs, including the cost of the capital tied up. It therefore differs from traditional accounting definitions of profit. In the original concept, within a sustainability framework, the "profit" aspect needs to be seen as the real economic benefit enjoyed by the host society. It is the real economic impact the organization has on its economic environment. This is often confused to be limited to the internal profit made by a company or organization (which nevertheless remains an essential starting point for the computation). Therefore, an original TBL approach cannot be interpreted as simply traditional corporate accounting profit "plus" social and environmental impacts unless the "profits" of other entities are included as a social benefit. Following the initial publication of the triple bottom line concept, students and practitioners have sought greater detail in how the pillars can be evaluated. The "people" concept for example can be viewed in three dimensions – organisational needs, individual needs, and community issues | https://en.wikipedia.org/wiki?curid=316929 | 463,667 |
Levich equation The models the diffusion and solution flow conditions around a rotating disk electrode (RDE). It is named after Veniamin Grigorievich Levich who first developed an RDE as a tool for electrochemical research. It can be used to predict the current observed at an RDE, in particular, the gives the height of the sigmoidal wave observed in rotating disk voltammetry. The sigmoidal wave height is often called the Levich current. The is written as: where "I" is the Levich current (A), "n" is the number of moles of electrons transferred in the half reaction (number), "F" is the Faraday constant (C/mol), "A" is the electrode area (cm), "D" is the diffusion coefficient (see Fick's law of diffusion) (cm/s), "ω" is the angular rotation rate of the electrode (rad/s), "v" is the kinematic viscosity (cm/s), "C" is the analyte concentration (mol/cm) To use the equation as written above (with the leading 0.620), radians per second for angular rotation units must be used. If revolution (rotations) per minute (rpm) are used, a value of 0.201 should be used in place of 0.620. Whereas the suffices for many purposes, improved forms based on derivations utilising more terms in the velocity expression are available. The is often simplified by defining a Levich constant "B" such that: | https://en.wikipedia.org/wiki?curid=20886466 | 10,249 |
Clienteling is a technique used by retail sales associates to establish long-term relationships with key customers based on data about their preferences, behaviors and purchases. is intended to guide associates to provide more personal and informed customer service that may influence customer behavior related to shopping frequency, lift in average transaction value, and other retail key performance indicators. From the customer's perspective, clienteling "could add a layer of personal touch" to the shopping experience. While at its core, clienteling is a sales technique, the term is commonly used today to describe the related assisted selling software tools used to support relationship-building activities between store associates and their customers. Software-based clienteling has been said to have the advantage of collecting data about clients across different interaction channels in a searchable and retrievable database for later use. software may also provide digital tools on mobile devices or fixed workstations aimed at enabling retailers to establish long-lasting learning relationships with their customers. While sales history collected in customer relationship management (CRM) platforms can provide some insight into a customer’s tendencies, this insight can be augmented by data collected by an associate working directly with a customer, who can improve the customer profile through each face-to-face interaction. This information can then be used to further personalize future interactions | https://en.wikipedia.org/wiki?curid=45372431 | 475,553 |
In situ chemical oxidation Permanganate only treats chlorinated solvents with double bonds and is easily used up by organic material in soil. Persulfate is more stable, treats a wider range of contaminants, and is not used up by soil organics as easily. Common oxidants used in this process are permanganate (both sodium permanganate and potassium permanganate), Fenton's Reagent, persulfate, and ozone. Other oxidants can be used, but these four are the most commonly used. Permanganate is used in groundwater remediation in the form of potassium permanganate () and sodium permanganate (). Both compounds have the same oxidizing capabilities and limitations and react similarly to contaminants. The biggest difference between the two chemicals is that potassium permanganate is less soluble than sodium permanganate. Potassium permanganate is a crystalline solid that is typically dissolved in water before application to the contaminated site. Unfortunately, the solubility of potassium permanganate is dependent on temperature. Because the temperature in the aquifer is usually less than the temperature in the area that the solution is mixed, the potassium permanganate becomes a solid material again. This solid material then does not react with the contaminants. Over time, the permanganate will become soluble again, but the process takes a long time. This compound has been shown to oxidize many different contaminants but is notable for oxidizing chlorinated solvents such as perchloroethylene (PCE), trichloroethylene (TCE), and vinyl chloride (VC) | https://en.wikipedia.org/wiki?curid=30833394 | 352,495 |
Solow residual The is a number describing empirical productivity growth in an economy from year to year and decade to decade. Robert Solow, the Nobel Memorial Prize in Economic Sciences-winning economist, defined rising productivity as rising output with constant capital and labor input. It is a "residual" because it is the part of growth that is not accounted for by measures of capital accumulation or increased labor input. Increased physical throughput – i.e. environmental resources – is specifically excluded from the calculation; thus some portion of the residual can be ascribed to increased physical throughput. The example used is for the intracapital substitution of aluminium fixtures for steel during which the inputs do not alter. This differs in almost every other economic circumstance in which there are many other variables. The Solow Residual is procyclical and measures of it are now called the rate of growth of multifactor productivity or total factor productivity, though Solow (1957) did not use these terms. In the 1950s, many economists undertook comparative studies of economic growth following World War II reconstruction. Some said that the path to long-term growth was achieved through investment in industry and infrastructure and in moving further and further into capital intensive automated production. Although there was always a concern about diminishing returns to this approach because of equipment depreciation, it was a widespread view of the correct industrial policy to adopt | https://en.wikipedia.org/wiki?curid=1827716 | 517,643 |
Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. The goal of human factors is to reduce human error, increase productivity, and enhance safety and comfort with a specific focus on the interaction between the human and the thing of interest. The field is a combination of numerous disciplines, such as psychology, sociology, engineering, biomechanics, industrial design, physiology, anthropometry, interaction design, visual design, user experience, and user interface design. In research, human factors employs the scientific method to study human behavior so that the resultant data may be applied to the four primary goals. In essence, it is the study of designing equipment, devices and processes that fit the human body and its cognitive abilities. The two terms "human factors" and "ergonomics" are essentially synonymous. The International Ergonomics Association defines ergonomics or human factors as follows: Human factors is employed to fulfill the goals of occupational health and safety and productivity. It is relevant in the design of such things as safe furniture and easy-to-use interfaces to machines and equipment. Proper ergonomic design is necessary to prevent repetitive strain injuries and other musculoskeletal disorders, which can develop over time and can lead to long-term disability | https://en.wikipedia.org/wiki?curid=36479878 | 476,327 |
Innovation leadership The patterns of characteristics creative workers exhibit typically allow them to confidently explore alternative ideas under ambiguous conditions. Successful innovation leadership requires a leader with certain characteristics. These include expertise in the domain, creativity, ability to carry out transformational leadership behaviors, planning and sense-making, and social skills. Innovative leaders can be recruited and hired through professional networks and referrals or alternatively found through succession planning, which involves identifying innovative leaders who are already working within the organization. In addition to these foundations, various styles play an important role in innovation leadership, each of which are used at different stages of the innovation process or for different types of innovation (value-added vs. exploratory). Frequently associated leadership styles include transformational leadership, transactional leadership, and Ambidextrous leadership. The type of leadership most strongly associated with innovation is transformational leadership. As mentioned above, different leadership styles and behaviors may be more appropriate at different stages of the innovation process. Current research supports the notion that in the idea generation process, innovation leadership requires a leader to use a more transformational style of leadership | https://en.wikipedia.org/wiki?curid=37375537 | 495,687 |
Tube socket The B7G (or "small-button" or "heptal") seven-pin miniature tubes are smaller than Noval, with seven pins arranged at 45-degree spacing in a 9.53 mm (3/8th inch) diameter arc, the "missing" pin position being used to position the tube in its socket (unlike octal, loctal and rimlock sockets). Examples include the 6AQ5/EL90 and 6BE6/EK90. European tubes of this type have numbers 90-99, 100-109, 190-199, 900-999. A few in the 100-109 series have unusual, non-B7G bases, "e.g.", Wehrmacht base. The nine-pin miniature Noval B9A base, sometimes called button 9-pin, B9-1, offered a useful reduction in physical size compared to previous common types, such as octal (especially important in TV receivers where space was limited), while also providing a sufficient number of connections (unlike B7G) to allow effectively unrestricted access to all the electrodes, even of relatively complex tubes such as double triodes and triode-hexodes. It could also provide multiple connections to an electrode of a simpler device where useful, as in the four connections to the grid of a conventional grounded-grid UHF triode, "e.g.", 6AM4, to minimise the deleterious effects of lead inductance on the high-frequency performance. This base type was used by many of the United States and most of the European tubes, "e.g.", 12AX7-ECC83, EF86 and EL84, produced commercially towards the end of the era before transistors largely displaced their use. The IEC 67-I-12a specification calls for a 36-degree angle between the nine pins of 1 | https://en.wikipedia.org/wiki?curid=1013793 | 389,947 |
Radio navigation The phase difference in degrees is transmitted to flight station navigational displays for use by the flight crew. The system is often able to be utilized with a compatible glideslope and marker beacon receiver, making the aircraft ILS-capable (Instrument Landing System). Once the aircraft's approach is accurate (the aircraft is in the "right place"), the VOR receiver will be used on a different frequency to determine if the aircraft is pointed in the "right direction." Military aircraft will usually employ two VOR receiver systems, one in VOR-only mode to determine "right place" and another in ILS mode in conjunction with a glideslope receiver to determine "right direction." The combination of both allows for a precision approach in foul weather. Beam systems broadcast narrow signals in the sky, and navigation is accomplished by keeping the aircraft centred in the beam. A number of stations are used to create an airway, with the navigator tuning in different stations along the direction of travel. These systems were common in the era when electronics were large and expensive, as they placed minimum requirements on the receivers – they were simply voice radio sets tuned to the selected frequencies. However, they did not provide navigation outside of the beams, and were thus less flexible in use. The rapid miniaturization of electronics during and after World War II made systems like VOR practical, and most beam systems rapidly disappeared | https://en.wikipedia.org/wiki?curid=153095 | 365,705 |
Malate dehydrogenase Additionally, the Arginine residues on the enzyme provide additional substrate specificity and binding through hydrogen bonding between the guanidinium side chain of the Arginine amino acid residues and the carboxylates of the substrate. Studies have also identified a mobile loop in malate dehydrogenase that participates in the catalytic activity of the enzyme. The loop undergoes a conformational change to shield the substrate and catalytic amino acids from the solvent in response to the binding of the malate dehydrogenase:coenzyme complex to substrate. This flipping of the loop to the up position to cover the active site also promotes enhanced interaction of the catalytically important amino residues on the enzyme with the substrate. Additionally, the movement of the loop has been shown to correlate with the rate determining step of the enzyme. Malate dehydrogenases catalyzes the interconversion of malate to oxaloacetate. In the citric acid cycle, malate dehydrogenase is responsible for catalyzing the regeneration of oxaloacetate This reaction occurs through the oxidation of hydroxyl group on malate and reduction of NAD. The mechanism of the transfer of the hydride ion to NAD is carried out in a similar mechanism seen in lactate dehydrogenase and alcohol dehydrogenase. The ΔG'° of malate dehydrogenase is +29.7 kJ/mol and the ΔG (in the cell) is 0 kJ/mol. is also involved in gluconeogenesis, the synthesis of glucose from smaller molecules | https://en.wikipedia.org/wiki?curid=1123842 | 50,361 |
Idle scan The hping method for idle scanning provides a lower level example for how idle scanning is performed. In this example the target host (172.16.0.100) will be scanned using an idle host (172.16.0.105). An open and a closed port will be tested to see how each scenario plays out. First, establish that the idle host is actually idle, send packets using hping2 and observe the id numbers increase incrementally by one. If the id numbers increase haphazardly, the host is not actually idle or has an OS that has no predictable IP ID. Send a spoofed SYN packet to the target host on a port you expect to be open. In this case, port 22 (ssh) is being tested. Since we spoofed the packet, we did not receive a reply and hping reports 100% packet loss. The target host replied directly to the idle host with a syn/ack packet. Now, check the idle host to see if the id number has increased. Notice that the proxy hosts id increased from id=1379 to id=1381. 1380 was consumed when the idle host replied to the target host's syn/ack packet with an rst packet. Run through the same processes again testing a port that is likely closed. Here we are testing port 23 (telnet). Notice that this time, the id did not increase because the port was closed. When we sent the spoofed packet to the target host, it replied to the idle host with an rst packet which did not increase the id counter | https://en.wikipedia.org/wiki?curid=8359417 | 357,026 |
Phylogenetics In biology, phylogenetics (Greek: φυλή, φῦλον – "phylé", "phylon" = tribe, clan, race + γενετικός – "genetikós" = origin, source, birth) is the study of the evolutionary history and relationships among individuals or groups of organisms (e.g. species, or populations). These relationships are discovered through phylogenetic inference methods that evaluate observed heritable traits, such as DNA sequences or morphology under a model of evolution of these traits. The result of these analyses is a phylogeny (also known as a phylogenetic tree)—a diagrammatic hypothesis about the history of the evolutionary relationships of a group of organisms. The tips of a phylogenetic tree can be living organisms or fossils, and represent the 'end', or the present, in an evolutionary lineage. A phylogenetic tree can be rooted or unrooted. A rooted tree indicates the common ancestor, or ancestral lineage, of the tree. An unrooted tree makes no assumption about the ancestral line, and does not show the origin or "root" of the gene or organism in question. Phylogenetic analyses have become central to understanding biodiversity, evolution, ecology, and genomes. Taxonomy is the identification, naming and classification of organisms. It is usually richly informed by phylogenetics, but remains a methodologically and logically distinct discipline | https://en.wikipedia.org/wiki?curid=23962 | 154,383 |
Edificio Victory Garden is a four-story apartment house that faces on Ponce de Leon Avenue and Elisa Colberg Street in the Miramar district of Santurce, Puerto Rico. It was deemed notable as "one of Puerto Rico's finest examples of Spanish Revival apartment houses from the early 20th century." The building was designed by Pedro Adolfo de Castro y Besosa (January 5, 1895-October, 1936), the first United States university-trained Puerto Rican architect. He designed 33 or more apartment houses during 1929–1936. Rafael Carmoega emerged to higher prominence only after de Castro's early death, at age 41. Although it appears massive, the building's footprint only uses up 30 percent of the lot's area. It is U-shaped with a courtyard not visible from the corner of the streets. | https://en.wikipedia.org/wiki?curid=50956691 | 326,396 |
Emotion and memory This has been demonstrated in lab studies with lists of words or pictures, in which people show impaired memory for stimuli appearing before or after arousing stimuli. Memory recall tends to be congruent with one's current mood, with depressed people more likely to recall negative events from the past. In addition, depression is often associated with poor memory in general, as outlined here. Several studies have demonstrated emotional memory enhancement in Alzheimer's patients suggesting that emotional memory enhancement might be used in the daily management of Alzheimer's patients. One study found that objects are recalled significantly better in Alzheimer's patients if they were presented as birthday presents to AD patients. The enhancing effects of emotional arousal on later memory recall tend to be maintained among older adults and the amygdala shows relatively less decline than many other brain regions. However, older adults also show somewhat of a shift towards favoring positive over negative information in memory, leading to a positivity effect. Emotional memory and sleep has been a well-researched association. Emotional memories are consolidated greater during sleep, rather than neutral memories. Studies have investigated high valence and arousing words, in comparison to neutral words. Sleep enhances the consolidation of the high valence and arousing words and therefore these are remembered more post-sleep | https://en.wikipedia.org/wiki?curid=21312317 | 146,886 |
Peak uranium An alternative to uranium is thorium which is three times more common than uranium. Fast breeder reactors are not needed. Compared to conventional uranium reactors, thorium reactors using the thorium fuel cycle may produce some 40 times the amount of energy per unit of mass. However, creating the technology, infrastructure and know-how needed for a "thorium-fuel economy" is uneconomical at current and predicted uranium prices. If nuclear power prices rise too quickly, or too high, power companies may look for substitutes in fossil energy (coal, oil, and gas) and/or renewable energy, such as hydro, bio-energy, solar thermal electricity, geothermal, wind, tidal energy. Both fossil energy and some renewable electricity sources (e.g. hydro, bioenergy, solar thermal electricity and geothermal) can be used as base-load. Prediction Technology Economics Art & Design Others | https://en.wikipedia.org/wiki?curid=15624586 | 376,266 |
Stannite (ion) The stannite ion is , or similar. Stannite ion can be formed by adding strong base to stannous hydroxide. Stannite ion is a strong reducing agent; also, it may disproportionate to tin metal plus stannate ion. There are stannite compounds, for example, sodium stannite, NaSnO. | https://en.wikipedia.org/wiki?curid=2671281 | 3,688 |
IMAX is a proprietary system of high-resolution cameras, film formats, film projectors, and theaters known for having very large screens with a tall aspect ratio (approximately 1.43:1 & 1.90:1) and steep stadium seating. Graeme Ferguson, Roman Kroitor, Robert Kerr, and William C. Shaw were the co-founders of what would be named the Corporation (founded in September 1967 as Multiscreen Corporation, Limited), and they developed the first cinema projection standards in the late 1960s and early 1970s in Canada. Unlike conventional film projectors, the film runs horizontally so that the image width can be greater than the width of the film stock. The film standard uses 70 mm film run through the projector horizontally. This technique produces an area that is nine times larger than the 35 mm format, and three times larger than 70 mm film which was run conventionally through the projector in a vertical orientation. The desire to increase the visual impact of film has a long history. In 1929, Fox introduced Fox Grandeur, the first 70 mm film format, but it quickly fell from use. In the 1950s, the potential of 35 mm film to provide wider projected images was explored in the processes of CinemaScope (1953) and VistaVision (1954), following multi-projector systems such as Cinerama (1952). While impressive, Cinerama was difficult to install and maintain, requiring careful alignment and synchronization of the multiple projectors | https://en.wikipedia.org/wiki?curid=173787 | 268,000 |
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