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1,656,163 | The ancient Chinese book of divination I Ching describes a hexagram as a permutation with repetitions of six lines where each line can be one of two states: solid or dashed. In describing hexagrams in this fashion they determine that there are formula_3 possible hexagrams. A Chinese monk also may have counted the number of configurations to a game similar to Go around 700 AD. Although China had relatively few advancements in enumerative combinatorics, around 100 AD they solved the Lo Shu Square which is the combinatorial design problem of the normal magic square of order three. Magic squares remained an interest of China, and they began to generalize their original formula_4 square between 900 and 1300 AD. China corresponded with the Middle East about this problem in the 13th century. The Middle East also learned about binomial coefficients from Indian work and found the connection to polynomial expansion. The work of Hindus influenced Arabs as seen in the work of al-Khalil ibn Ahmad who considered the possible arrangements of letters to form syllables. His calculations show an understanding of permutations and combinations. In a passage from the work of Arab mathematician Umar al-Khayyami that dates to around 1100, it is corroborated that the Hindus had knowledge of binomial coefficients, but also that their methods reached the middle east. | https://en.wikipedia.org/wiki?curid=20885039 | 1,655,230 |
1,062,543 | MEAs have been used to interface neuronal networks with non-biological systems as a controller. For example, a neural-computer interface can be created using MEAs. Dissociated rat cortical neurons were integrated into a closed stimulus-response feedback loop to control an animat in a virtual environment. A closed-loop stimulus-response system has also been constructed using an MEA by Potter, Mandhavan, and DeMarse, and by Mark Hammond, Kevin Warwick, and Ben Whalley in the University of Reading. About 300,000 dissociated rat neurons were plated on an MEA, which was connected to motors and ultrasound sensors on a robot, and was conditioned to avoid obstacles when sensed. Along these lines, Shimon Marom and colleagues in the Technion hooked dissociated neuronal networks growing on MEAs to a Lego Mindstorms robot; the visual field of the robot was classified by the network, and commands were delivered to the robot wheels such that it completely avoids bumping into obstacles. This "Braitenberg vehicle" was used to demonstrate the indeterminacy of reverse neuro-engineering showing that even in a simple setup with practically unlimited access to every piece of relevant information, it was impossible to deduce with certainty the specific neural coding scheme that was used to drive the robots behavior. | https://en.wikipedia.org/wiki?curid=20511935 | 1,061,989 |
1,521,449 | Definitive diagnosis requires laboratory effort. Culture, histopathology and immunology can be used to for the diagnosis. First, a portion of the infected tissue will be surgically removed and used for a biopsy. Since the fungus can not tolerate refrigeration, the biopsied material needs to be incubated immediately once it is collected. Then, the examination will investigate the presence of thin-walled, wide, hyaline, coenocytic hyphae and internal cleavage for the production of the sporangiospores in H&E (Haemotoxylin and Eosin) stained sections. Other characteristics of its appearance mentioned in the morphology section might also be used to identify the species. Moreover, the histopathology test will expect a granuloma consisting of a variety of immune cells in which hypha or hyphal fragments (4–10 μm diameter) often stain bright pink in H&E sections. When biopsy is not available, immunofluorescent test can also be used to identify "B. ranarum" strains. Five specific antigens have been identified that can be used measured in the sera of the infected patients using antibodies conjugated to fluorescein dye. The diagnosis of the rare cases, such as gastrointestinal basidiobolomycosis, is challenging given the nonspecific clinical presentation as well as the need for surgical biopsy. | https://en.wikipedia.org/wiki?curid=7041908 | 1,520,588 |
1,308,396 | Anti-tamper protection can be applied as either internally or externally to the application being protected. External anti-tampering is normally accomplished by monitoring the software to detect tampering. This type of defense is commonly expressed as malware scanners and anti-virus applications. Internal anti-tampering is used to turn an application into its own security system and is generally done with specific code within the software that will detect tampering as it happens. This type of tamper proofing defense may take the form of runtime integrity checks such as cyclic redundancy checksums, anti-debugging measures, encryption or obfuscation. Execution inside a virtual machine has become a common anti-tamper method used in recent years for commercial software; it is used for example in StarForce and SecuROM. Some anti-tamper software uses white-box cryptography, so cryptographic keys are not revealed even when cryptographic computations are being observed in complete detail in a debugger. A more recent research trend is tamper-tolerant software, which aims to correct the effects of tampering and allow the program to continue as if unmodified. A simple (and easily defeated) scheme of this kind was used in the Diablo II video game, which stored its critical player data in two copies at different memory locations and if one was modified externally, the game used the lower value. | https://en.wikipedia.org/wiki?curid=35682554 | 1,307,680 |
259,365 | Cellular automata are often simulated on a finite grid rather than an infinite one. In two dimensions, the universe would be a rectangle instead of an infinite plane. The obvious problem with finite grids is how to handle the cells on the edges. How they are handled will affect the values of all the cells in the grid. One possible method is to allow the values in those cells to remain constant. Another method is to define neighborhoods differently for these cells. One could say that they have fewer neighbors, but then one would also have to define new rules for the cells located on the edges. These cells are usually handled with a "toroidal" arrangement: when one goes off the top, one comes in at the corresponding position on the bottom, and when one goes off the left, one comes in on the right. (This essentially simulates an infinite periodic tiling, and in the field of partial differential equations is sometimes referred to as "periodic" boundary conditions.) This can be visualized as taping the left and right edges of the rectangle to form a tube, then taping the top and bottom edges of the tube to form a torus (doughnut shape). Universes of other dimensions are handled similarly. This solves boundary problems with neighborhoods, but another advantage is that it is easily programmable using modular arithmetic functions. For example, in a 1-dimensional cellular automaton like the examples below, the neighborhood of a cell "x" is {"x", "x", "x"}, where "t" is the time step (vertical), and "i" is the index (horizontal) in one generation. | https://en.wikipedia.org/wiki?curid=54342 | 259,231 |
955,026 | The first discoveries that contributed to the development of biogeography as a science began in the mid-18th century, as Europeans explored the world and described the biodiversity of life. During the 18th century most views on the world were shaped around religion and for many natural theologists, the bible. Carl Linnaeus, in the mid-18th century, initiated the ways to classify organisms through his exploration of undiscovered territories. When he noticed that species were not as perpetual as he believed, he developed the Mountain Explanation to explain the distribution of biodiversity; when Noah's ark landed on Mount Ararat and the waters receded, the animals dispersed throughout different elevations on the mountain. This showed different species in different climates proving species were not constant. Linnaeus' findings set a basis for ecological biogeography. Through his strong beliefs in Christianity, he was inspired to classify the living world, which then gave way to additional accounts of secular views on geographical distribution. He argued that the structure of an animal was very closely related to its physical surroundings. This was important to a George Louis Buffon's rival theory of distribution. | https://en.wikipedia.org/wiki?curid=99358 | 954,521 |
785,499 | Anthropology grew increasingly distinct from natural history and by the end of the nineteenth century the discipline began to crystallize into its modern form—by 1935, for example, it was possible for T.K. Penniman to write a history of the discipline entitled "A Hundred Years of Anthropology". At the time, the field was dominated by 'the comparative method'. It was assumed that all societies passed through a single evolutionary process from the most primitive to most advanced. Non-European societies were thus seen as evolutionary 'living fossils' that could be studied in order to understand the European past. Scholars wrote histories of prehistoric migrations which were sometimes valuable but often also fanciful. It was during this time that Europeans first accurately traced Polynesian migrations across the Pacific Ocean for instance—although some of them believed it originated in Egypt. Finally, the concept of race was actively discussed as a way to classify—and rank—human beings based on difference. | https://en.wikipedia.org/wiki?curid=1676362 | 785,078 |
688,378 | The reentry module was completely covered in ablative heat shield material, in diameter, weighing . The capsule was covered with a nose cone to maintain a low-drag profile for launch, with a cylindrical interior cabin approximately in diameter nearly perpendicular to the capsule's longitudinal axis. The cosmonaut sat in an ejection seat with a separate parachute for escape during a launch emergency and landing during a normal flight. The capsule had its own parachute for landing on the ground. Although official sources stated that Gagarin had landed inside his capsule, a requirement for qualifying as a first crewed spaceflight under International Aeronautical Federation (IAF) rules, it was later revealed that all Vostok cosmonauts ejected and landed separately from the capsule. The capsule was serviced by an aft-facing conical equipment module long by , weighing containing nitrogen and oxygen breathing gasses, batteries, fuel, attitude control thrusters, and the retrorocket. It could support flights as long as ten days. Six Vostok launches were successfully conducted, the last two pairs in concurrent flights. The longest flight was just short of five days, on Vostok 5 on June 14–19, 1963. | https://en.wikipedia.org/wiki?curid=1059613 | 688,020 |
1,122,437 | Members from the J. Craig Venter Institute have used a top-down computational approach to knock out genes in a living organism to a minimum set of genes. In 2010, the team succeeded in creating a replicating strain (named Mycoplasma laboratorium) of "Mycoplasma mycoides" using synthetically created DNA deemed to be the minimum requirement for life which was inserted into a genomically empty bacterium. It is hoped that the process of top-down biosynthesis will enable the insertion of new genes that would perform profitable functions such as generation of hydrogen for fuel or capturing excess carbon dioxide in the atmosphere. The myriad regulatory, metabolic, and signaling networks are not completely characterized. These top-down approaches have limitations for the understanding of fundamental molecular regulation, since the host organisms have a complex and incompletely defined molecular composition. In 2019 a complete computational model of all pathways in Mycoplasma Syn3.0 cell was published, representing the first complete in silico model for a living minimal organism. | https://en.wikipedia.org/wiki?curid=4630125 | 1,121,863 |
1,970,207 | The Mobile Stroke Unit concept was first published in 2003 and realized in clinical practice in 2008 by Fassbender et al. at Saarland University, Germany, adhering to current guidelines and legislations. This strategy of "bringing the hospital to the patient" strongly reduced time between alarm and therapy, allowing diagnosis-based triage to the appropriate target hospital and other novel option such as diagnosis-based blood pressure adjustment. It increased treatment rates and improved care of cerebral hemorrhage, when compared to conventional in-hospital care as shown by them and other groups at Berlin, Germany; Houston, Texas, USA; Cleveland, Ohio, USA; or Drøbak and Oslo, Norway. In 2016, more than 20 sites are investigating this concept. Further studies on long-term outcomes, cost-effectiveness and best setting are underway. | https://en.wikipedia.org/wiki?curid=52360905 | 1,969,073 |
1,145,496 | Basic understanding of neuroimmunological diseases has changed significantly during the last ten years. New data broadening the understanding of new treatment concepts has been obtained for a large number of neuroimmunological diseases, none more so than multiple sclerosis, since many efforts have been undertaken recently to clarify the complexity of pathomechanisms of this disease. Accumulating evidence from animal studies suggests that some aspects of depression and fatigue in MS may be linked to inflammatory markers. Studies have demonstrated that Toll like-receptor (TLR4) is critically involved in neuroinflammation and T cell recruitment in the brain, contributing to exacerbation of brain injury. Research into the link between smell, depressive behavior, and autoimmunity has turned up interesting findings including the facts that inflammation is common in all of the diseases analyzed, depressive symptoms appear early in the course of most diseases, smell impairment is also apparent early in the development of neurological conditions, and all of the diseases involved the amygdale and hippocampus. Better understanding of how the immune system functions and what factors contribute to responses are being heavily investigated along with the aforementioned coincidences. | https://en.wikipedia.org/wiki?curid=4052447 | 1,144,895 |
332,993 | Due to exposure to atomic radiation, Doctor Octopus has acquired the mental ability of psychokinetic control over the four electrically powered, telescoping, prehensile, titanium-steel artificial tentacle "arms" (a degree of psychokinetic control over them that he can also exercise over vast distances even when they are not connected to him) that are attached to a stainless-steel harness encompassing his lower torso. Each of these four arms is capable of lifting several tons, provided that at least one arm is used to support his body. The reaction time and agility of his mechanical appendages are enhanced far beyond the range attainable for normal human musculature. The arms allow Octavius to move rapidly over any terrain and to scale vertical surfaces and ceilings. He has developed his concentration and control to the point that he can engage a single opponent, like Spider-Man, or multiple opponents with the arms while performing a completely separate, more delicate task, such as stirring coffee or constructing a machine. Due to his weight and age, his opponents are often lured into a false sense of security, only to find he is a formidable combatant. He has managed to force opponents as formidable as Spider-Man, Daredevil, and Captain America to take up a defensive position in a fight. | https://en.wikipedia.org/wiki?curid=315873 | 332,815 |
1,964,596 | Nanoparticles have promising therapeutic effects when treating neurodegenerative diseases. Oxygen reactive polymer (ORP) is a nano-platform programmed to react with oxygen and has been shown to detect and reduce the presence of reactive oxygen species (ROS) formed immediately after traumatic brain injuries. Nanoparticles have also been employed as a “neuroprotective” measure, as is the case with Alzheimer’s disease and stroke models. Alzheimer’s disease results in toxic aggregates of the amyloid beta protein formed in the brain. In one study, gold nanoparticles were programmed to attach themselves to these aggregates and were successful in breaking them up. Likewise, with ischemic stroke models, cells in the affected region of the brain undergo apoptosis, dramatically reducing blood flow to important parts of the brain and often resulting in death or severe mental and physical changes. Platinum nanoparticles have been shown to act as ROS, serving as “biological antioxidants” and significantly reducing oxidation in the brain as a result of stroke. Nanoparticles can also lead to neurotoxicity and cause permanent BBB damage either from brain oedema or from unrelated molecules crossing the BBB and causing brain damage. This proves further long term in vivo studies are needed to gain enough understanding to allow for successful clinical trials. | https://en.wikipedia.org/wiki?curid=67633513 | 1,963,468 |
1,854,260 | A Chicagoan, Deno had an interest in plants from a young age, but obtained a post-doctoral degree in chemistry as a more lucrative career opportunity. His chemistry professor position at Penn State University resulted in a discovery by his lab on coal refinement for oil refineries that earned him a large amount of wealth from grants. He later reduced his focus on chemistry to pursue his interests in horticulture. Determining the germination requirements for plants had Deno create the "baggie and paper towel" method for mimicking laboratory growth settings and his general low tech methodologies would end up being dubbed "The Deno Method". His approach to seed germination would result in multiple interviews in newspapers and for books, along with seed companies coming to him specifically for specific cultivar research. He went on to publish multiple books covering seed germination theory and he received awards from the North American Rock Garden Society for his work. | https://en.wikipedia.org/wiki?curid=66739039 | 1,853,197 |
929,970 | Attempts to use a "Sloika" design to achieve megaton-range results proved unfeasible in the Soviet Union as it had in the calculations done in the US, but its value as a practical weapon since it was 20 times more powerful than their first fission bomb, should not be underestimated. The Soviet physicists calculated that at best the design might yield a single megaton of energy if it was pushed to its limits. After the US tested the "Ivy Mike" device in 1952, proving that a multimegaton bomb could be created, the Soviets searched for an additional design and continued to work on improving the "Sloika" (the "First Idea"). The "Second Idea", as Sakharov referred to it in his memoirs, was a previous proposal by Ginzburg in November 1948 to use lithium deuteride in the bomb, which would, by the bombardment by neutrons, produce tritium. In late 1953, physicist Viktor Davidenko achieved the first breakthrough, that of keeping the "primary" and the "secondary" parts of the bombs in separate pieces ("staging"). The next breakthrough was discovered and developed by Sakharov and Yakov Zeldovich, that of using the X-rays from the fission bomb to compress the "secondary" before fusion ("radiation implosion"), in the spring of 1954. Sakharov's "Third Idea", as the Teller–Ulam design was known in the Soviet Union, was tested in the shot "RDS-37" in November 1955 with a yield of . | https://en.wikipedia.org/wiki?curid=2451331 | 929,479 |
1,193,693 | Unlike some Western countries, the majority of the research programmes are conducted not at the institutions (such as universities) but at specially set up research facilities and institutes. These institutes are performed under the government's Ministry of Science that overlooks the development and promotion of science in the country, while others are performed under the Pakistan Academy of Sciences, other specialized academies and even the research arms of various government ministries. At first, the core of fundamental science was the Pakistan Academy of Sciences, originally set up in 1953 and moved from Karachi to Islamabad in 1964. The Pakistan Academy of Sciences has a large percentage of researchers in the natural sciences, particularly physics. From 1947 to 1971, the research was being conducted independently with no government influence. The High Tension Laboratories (HTL) at the Government College University, Lahore (GCU) was established by R. M. Chaudhry with funds given by the British government in the 1950s. In 1967, Professor Abdus Salam led the foundation of the Institute of Theoretical Physics (ITP) at the Quaid-e-Azam University, and the establishment of the Pakistan Institute of Nuclear Science and Technology (PINSTECH) and the Centre for Nuclear Studies; all were independently established by Pakistan's academic scientists with financial assistance provided by European countries. However, after Zulfikar Ali Bhutto became president, he took control of scientific research in 1972 as part of his intensified socialist reforms and policies. With advice taken from Dr. Mubashir Hassan, Bhutto established the Ministry of Science with Ishrat Hussain Usmani, a bureaucrat with a doctorate in atomic physics. | https://en.wikipedia.org/wiki?curid=20722416 | 1,193,054 |
1,380,965 | The technique is used in conjunction with an ultramicroscope and a laser illumination unit that together allow small particles in liquid suspension to be visualized moving under Brownian motion. The light scattered by the particles is captured using a CCD or EMCCD camera over multiple frames. Computer software is then used to track the motion of each particle from frame to frame. The rate of particle movement is related to a sphere equivalent hydrodynamic radius as calculated through the Stokes–Einstein equation. The technique calculates particle size on a particle-by particle basis, overcoming inherent weaknesses in ensemble techniques such as dynamic light scattering. Since video clips form the basis of the analysis, accurate characterization of real time events such as aggregation and dissolution is possible. Samples require minimal preparation, minimizing the time required to process each sample. Speculators suggest that eventually the analysis may be done in real-time with no preparation, e.g. when detecting the presence of airborne viruses or biological weapons. | https://en.wikipedia.org/wiki?curid=4366478 | 1,380,202 |
212,352 | A double degenerate scenario is one of several explanations proposed for the anomalously massive () progenitor of SN 2003fg. It is the only possible explanation for SNR 0509-67.5, as all possible models with only one white dwarf have been ruled out. It has also been strongly suggested for SN 1006, given that no companion star remnant has been found there. Observations made with NASA's Swift space telescope ruled out existing supergiant or giant companion stars of every Type Ia supernova studied. The supergiant companion's blown out outer shell should emit X-rays, but this glow was not detected by Swift's XRT (X-ray telescope) in the 53 closest supernova remnants. For 12 Type Ia supernovae observed within 10 days of the explosion, the satellite's UVOT (ultraviolet/optical telescope) showed no ultraviolet radiation originating from the heated companion star's surface hit by the supernova shock wave, meaning there were no red giants or larger stars orbiting those supernova progenitors. In the case of SN 2011fe, the companion star must have been smaller than the Sun, if it existed. The Chandra X-ray Observatory revealed that the X-ray radiation of five elliptical galaxies and the bulge of the Andromeda Galaxy is 30–50 times fainter than expected. X-ray radiation should be emitted by the accretion discs of Type Ia supernova progenitors. The missing radiation indicates that few white dwarfs possess accretion discs, ruling out the common, accretion-based model of Ia supernovae. Inward spiraling white dwarf pairs are strongly-inferred candidate sources of gravitational waves, although they have not been directly observed. | https://en.wikipedia.org/wiki?curid=3728323 | 212,244 |
640,318 | Axon branches retract in a distal to proximal manner. The axonal contents that are retracted are thought to be recycled to other parts of the axon. The biological mechanism with which axonal pruning occurs still remains unclear for the mammalian central nervous system. However, pruning has been associated with guidance molecules in mice. Guidance molecules serve to control axon pathfinding through repulsion, and also initiate pruning of exuberant synaptic connections. Semaphorin ligands and the receptors neuropilins and plexins are used to induce retraction of the axons to initiate hippocampo-septal and infrapyramidal bundle (IPB) pruning. Stereotyped pruning of the hippocampal projections have been found to be significantly impaired in mice that have a Plexin-A3 defect. Specifically, axons that are connected to a transient target will retract once the Plexin-A3 receptors are activated by class 3 semaphorin ligands. In IPB, the expression of mRNA for Sema3F is present in the hippocampus prenatally, lost postnatally and returns in the stratum oriens. Coincidentally, onset IPB pruning occurs around the same time. In the case of the hippocampal-septal projections, expression of mRNA for Sema3A was followed by the initiation of pruning after 3 days. This suggests that pruning is triggered once the ligand reaches threshold protein levels within a few days after detectable mRNA expression. Pruning of axons along the visual corticospinal tract (CST) is defective in neuropilin-2 mutants and plexin-A3 and plexin-A4 double mutant mice. Sema3F is also expressed in the dorsal spinal cord during the pruning process. There is no motor CST pruning defect observed in these mutants. | https://en.wikipedia.org/wiki?curid=9185670 | 639,979 |
976,408 | The klystron was the first significantly powerful source of radio waves in the microwave range; before its invention the only sources were the Barkhausen–Kurz tube and split-anode magnetron, which were limited to very low power. It was invented by the brothers Russell and Sigurd Varian at Stanford University. Their prototype was completed and demonstrated successfully on August 30, 1937. Upon publication in 1939, news of the klystron immediately influenced the work of US and UK researchers working on radar equipment. The Varians went on to found Varian Associates to commercialize the technology (for example, to make small linear accelerators to generate photons for external beam radiation therapy). Their work was preceded by the description of velocity modulation by A. Arsenjewa-Heil and Oskar Heil (wife and husband) in 1935, though the Varians were probably unaware of the Heils' work. | https://en.wikipedia.org/wiki?curid=234132 | 975,897 |
364,337 | At 11:28 pm local time on 3 March 2022, a column of 10 Russian armored vehicles and two tanks approached the power plant. Fighting commenced at 12:48am on 4 March when Ukraine forces fired anti-tank missiles. Russian forces responded with a variety of weapons, including rocket-propelled grenades. During approximately two hours of heavy combat, a fire broke out in a training facility outside the main complex, which was extinguished by 6:20am, though other sections surrounding the plant sustained damage. The fire did not impact reactor safety or any essential equipment. The plant lost 1.3 GW of capacity. It was later learned that a large caliber bullet pierced an outer wall of Reactor No. 4 and an artillery shell hit a transformer at Reactor No. 6. | https://en.wikipedia.org/wiki?curid=1763005 | 364,147 |
1,727,716 | Ambiophonics is an amalgam of new research and previously known psychoacoustic principles and binaural technologies. This knowledge has enabled audio recording and reproduction that approaches the realistic soundfield at the ears of the listener that is comparable to what one would perceive in a concert hall, movie scene, or game environment. This level of high-fidelity was not realizable until human hearing and acoustics principles were thoroughly researched, and affordable PCs with sufficient processing speed became available. At the Casa Della Musica at the University of Parma, Italy, or at the listening lab at Filmaker Technology, Pennsylvania, US, ambiophonics, ambisonics, stereophonics, 5.1 2D surround, and hybrid full-sphere 3D systems can be compared for the abilities of these methods to convey the spatiality and tone color of real perception. Developers have provided many scientific papers and downloadable tools for implementing ambiophonics free of charge for personal use. | https://en.wikipedia.org/wiki?curid=15773993 | 1,726,742 |
383,035 | If the patient's blood pressure is moderately elevated, a selective, short-acting alpha-1 adrenoceptor antagonist (doxazosin, prazosin, terazosin) is the preferred agent. However, the patient should be warned about the potential side-effect known as "the first-dose phenomenon." When patients are initially exposed to one of the above agents, they may become lightheaded, dizzy, and nauseous, particularly when transferring from a seated to standing position due to a rapid decrease in blood pressure. These effects will decrease with time, but providers can try to avoid them by starting at a low-dose and slowly increasing until they reach their desired amount. In patient's with uncontrolled hypertension, the non-selective alpha-1 and 2 adrenoceptor antagonist (phenoxybenzamine) should be utilized. Unfortunately, compared to the selective agents listed above, phenoxybenzamine is much more expensive and may not be readily available to some patients. Common side-effects include dry mouth, nasal congestion, and impaired male ejaculation, all of which do not cease with time and may limit patient compliance. While uncommon, patients may have a hormonally-active pheochromocytoma and a normal blood pressure. One comparison from 2014 found that a small dose of a calcium-channel blocker (such as amlodipine) may be used pre-operatively in some people. This will not drastically lower the patients blood pressure and make them hypotensive, but it will assist the surgical and anesthesia teams if there is hemodynamic instability during the operation. | https://en.wikipedia.org/wiki?curid=277088 | 382,840 |
1,174,251 | The original aim of the IASC was to issue 'basic' standards. In practice, this meant that the standards often reflected common, rather than best practices in the board member countries. Several standards contained alternative treatments (options), reflecting the diversity of practice. For instance, IAS 2 "Valuation and Presentation of Inventories in the Context of the Historical Cost System" (1975) allowed a variety of practices including the LIFO, FIFO and base stock methods. For this reason, the IASC was sometimes criticized for taking a 'lowest common denominator' approach. However, some of the early standards prescribed practices that were not yet commonly followed in many countries, including several board member countries. IAS 3 "Consolidated Financial Statements and the Equity Method of Accounting" (1976) required the presentation of consolidated financial statements by parents of subsidiary companies. This was well before the Seventh Company Law Directive (1983) made this mandatory in the member states of the European Economic Community. IAS 17 "Accounting for Leases" (1982) required the capitalization of finance leases, a practice that was as yet unusual or unknown outside the United States. | https://en.wikipedia.org/wiki?curid=182313 | 1,173,629 |
1,025,471 | Cell theory led biologists to re-envision individual organisms as interdependent assemblages of individual cells. Scientists in the rising field of cytology, armed with increasingly powerful microscopes and new staining methods, soon found that even single cells were far more complex than the homogeneous fluid-filled chambers described by earlier microscopists. Robert Brown had described the nucleus in 1831, and by the end of the 19th century cytologists identified many of the key cell components: chromosomes, centrosomes mitochondria, chloroplasts, and other structures made visible through staining. Between 1874 and 1884 Walther Flemming described the discrete stages of mitosis, showing that they were not artifacts of staining but occurred in living cells, and moreover, that chromosomes doubled in number just before the cell divided and a daughter cell was produced. Much of the research on cell reproduction came together in August Weismann's theory of heredity: he identified the nucleus (in particular chromosomes) as the hereditary material, proposed the distinction between somatic cells and germ cells (arguing that chromosome number must be halved for germ cells, a precursor to the concept of meiosis), and adopted Hugo de Vries's theory of pangenes. Weismannism was extremely influential, especially in the new field of experimental embryology. | https://en.wikipedia.org/wiki?curid=322460 | 1,024,938 |
328,870 | After exiting the hardware business, NeXT focused on other operating systems. New products based on OpenStep were released, including OpenStep Enterprise, a version for Microsoft's Windows NT. NeXT launched WebObjects, a platform for building large-scale dynamic web applications. It failed to achieve wide popularity, partly because of the initial high price of US$50,000; but it remains the first and most prominent early example of a web application server that enabled dynamic page generation based on user interactions as opposed to static content. The platform was bundled with macOS Server and Xcode, but was removed in 2009 and discontinued in 2016. It was used for a short of period of time by many large businesses, including Dell, Disney, WorldCom, and the BBC. WebObjects would eventually be used to power Apple's iTunes Store and most of its corporate website until the iTunes Store was discontinued in August 2017. | https://en.wikipedia.org/wiki?curid=21694 | 328,696 |
666,394 | In a similar synthesis experiment a frozen mixture of water, methanol, ammonia and carbon monoxide was exposed to ultraviolet (UV) radiation. This combination yielded large amounts of organic material that self-organised to form globules or vesicles when immersed in water. The investigating scientist considered these globules to resemble cell membranes that enclose and concentrate the chemistry of life, separating their interior from the outside world. The globules were between , or about the size of red blood cells. Remarkably, the globules fluoresced, or glowed, when exposed to UV light. Absorbing UV and converting it into visible light in this way was considered one possible way of providing energy to a primitive cell. If such globules played a role in the origin of life, the fluorescence could have been a precursor to primitive photosynthesis. Such fluorescence also provides the benefit of acting as a sunscreen, diffusing any damage that otherwise would be inflicted by UV radiation. Such a protective function would have been vital for life on the early Earth, since the ozone layer, which blocks out the sun's most destructive UV rays, did not form until after photosynthetic life began to produce oxygen. | https://en.wikipedia.org/wiki?curid=19179678 | 666,046 |
1,036,373 | The patent became more fuel for the ongoing controversy over the issue of software patents. This left many mathematicians uneasy, such as Ronald Rivest (himself one of the holders of the patent on the RSA algorithm), who expressed the opinion that research proceeded on the basis that algorithms should be free. Even before the patent was actually granted, it was argued that there might have been prior art that was applicable. Mathematicians who specialized in numerical analysis, including Philip Gill and others, claimed that Karmarkar's algorithm is equivalent to a projected Newton barrier method with a logarithmic barrier function, if the parameters are chosen suitably. Legal scholar Andrew Chin opines that Gill's argument was flawed, insofar as the method they describe does not constitute an "algorithm", since it requires choices of parameters that don't follow from the internal logic of the method, but rely on external guidance, essentially from Karmarkar's algorithm. Furthermore, Karmarkar's contributions are considered far from obvious in light of all prior work, including Fiacco-McCormick, Gill and others cited by Saltzman. The patent was debated in the U.S. Senate and granted in recognition of the essential originality of Karmarkar's work, as : "Methods and apparatus for efficient resource allocation" in May 1988. | https://en.wikipedia.org/wiki?curid=3736667 | 1,035,833 |
285,633 | On 2 May 2019, Bombardier's aerospace division was renamed "Bombardier Aviation" following the divestment of the CSeries and Q400 programmes. On 25 June 2019, Bombardier agreed with Mitsubishi Heavy Industries to sell the CRJ program, a deal was expected to close in early 2020 subject to regulatory approval. Mitsubishi will gain Bombardier's global expertise in terms of engineering, certification, customer relations and support, boosting its SpaceJet (formerly MRJ) programme and enabling its production in North America. The deal includes two service centres in Canada and two in the US, as well as the CRJ's type certificates. Bombardier retains the Mirabel assembly facility and produce the CRJ on behalf of Mitsubishi until the current order backlog is complete. In early May 2020, Mitsubishi confirmed that all conditions had been met. The transaction closed on 1 June. Bombardier's CRJ-related service and support activities were transferred to a new Montreal-based company, MHI RJ Aviation Group. | https://en.wikipedia.org/wiki?curid=81581 | 285,479 |
675,462 | Sterrasters/selenasters are big enough to examine in some detail their surfaces with an optical microscope. However, the use of the scanning electron microscope (SEM) enabled a significantly better understanding of the surface microornamentations. A few descriptive terms have also appeared to describe and compare in greater detail the microornamentations of these ball-shaped spicules. spicules such as the sterrasters and aspidasters, are the result of fused "actines" (= branches of asters, from the Greek for "star"), later covered with "rosettes" made of different "rays". The "hilum" (Latin for a "little thing" or "trifle" or the "eye of a bean") is a small area without rosettes or any kind of surface pattern. There are no particular terms to describe the surface of selenasters, except for the "hilum", also present. Although there appears to be no significant variation in the size of the rosettes and hilum between species, noticed that rosettes could be smooth or warty and hypothesized that this character could be of phylogenetic value if studied more broadly. Furthermore, the rosette morphology also seemed to be variable between "Geodia", "Pachymatisma", and "Caminella" which suggests that a more detailed study of the sterraster/aspidaster surface would potentially bring new characters for Geodiidae genera identification. | https://en.wikipedia.org/wiki?curid=27140295 | 675,109 |
33,012 | The B-17's greatest success in the Pacific was in the Battle of the Bismarck Sea, in which aircraft of this type were responsible for damaging and sinking several Japanese transport ships. On 2 March 1943, six B-17s of the 64th Squadron flying at attacked a major Japanese troop convoy off New Guinea, using skip bombing to sink , which carried 1,200 army troops, and damage two other transports, "Teiyo Maru" and "Nojima". On 3 March 1943, 13 B-17s flying at bombed the convoy, forcing the convoy to disperse and reducing the concentration of their anti-aircraft defenses. The B-17s attracted a number of Mitsubishi A6M Zero fighters, which were in turn attacked by the P-38 Lightning escorts. One B-17 broke up in the air, and its crew was forced to take to their parachutes. Japanese fighter pilots machine-gunned some of the B-17 crew members as they descended and attacked others in the water after they landed. Five of the Japanese fighters strafing the B-17 aircrew were promptly engaged and shot down by three Lightnings, though these were also then lost. The allied fighter pilots claimed 15 Zeros destroyed, while the B-17 crews claimed five more. Actual Japanese fighter losses for the day were seven destroyed and three damaged. The remaining seven transports and three of the eight destroyers were then sunk by a combination of low level strafing runs by Royal Australian Air Force Beaufighters, and skip bombing by USAAF North American B-25 Mitchells at , while B-17s claimed five hits from higher altitudes. On the morning of 4 March 1943, a B-17 sank the destroyer "Asashio" with a bomb while she was picking up survivors from "Arashio". | https://en.wikipedia.org/wiki?curid=4997 | 33,000 |
2,062,188 | The decline in industrial research spending is of particular concern. Expenditure on industrial R&D as a share of GDP amounts to only half the OECD average. Foreign-controlled firms account for one-third of all in-house research and development, a persistent trend over recent decades. In 2017, the government allocated Can$950 million over a five-year period to support innovative ‘superclusters’ to spur public–private collaboration on the ocean economy, next-generation manufacturing, digital technology, protein industries and artificial intelligence. In so doing, the government is challenging Canadian enterprises to enter into collaborative partnerships with research institutions, in order to develop ‘bold and ambitious’ innovation strategies. The government expects the initiative to result in the creation of 50 000 jobs over ten years. | https://en.wikipedia.org/wiki?curid=18401364 | 2,060,998 |
353,580 | In 2016, NASA SHERLOC co-investigator Dr. Marc Fries — with help from his son Wyatt — was inspired by Geocaching's 2008 placement of a cache on the International Space Station to set out and try something similar with the rover mission. After floating the idea around mission management, it eventually reached NASA scientist Francis McCubbin, who would join the SHERLOC instrument team as a collaborator to move the project forward. The Geocaching inclusion was scaled-down to a trackable item that players could search for from NASA camera views and then log on to the site. In a manner similar to the "Send Your Name to Mars" campaign, the geocaching trackable code was carefully printed on a one-inch, polycarbonate glass disk serving as part of the rover's calibration target. It will serve as an optical target for the WATSON imager and a spectroscopic standard for the SHERLOC instrument. The disk is made of a prototype astronaut helmet visor material that will be tested for its potential use in crewed missions to Mars. Designs were approved by the mission leads at NASA's Jet Propulsion Laboratory (JPL), NASA Public Affairs, and NASA HQ, in addition to Groundspeak Geocaching HQ. | https://en.wikipedia.org/wiki?curid=63297153 | 353,397 |
1,759,453 | In the last ten years, the sensitivity of the method was improved by an optimization of the surface chemistry as well as dedicated protocols for their chemical labeling. Currently, the sensitivity of antibody arrays is comparable to that of ELISA and antibody arrays are regularly used for profiling experiments on tissue samples, plasma or serum samples and many other sample types. One main focus in antibody array based profiling studies is biomarker discovery, specifically for cancer. For cancer-related research, the development and application of an antibody array comprising 810 different cancer-related antibodies was reported in 2010. Also in 2010, an antibody array comprising 507 cytokines, chemokines, adipokines, growth factors, angiogenic factors, proteases, soluble receptors, soluble adhesion molecules, and other proteins was used to screen the serum of ovarian cancer patients and healthy individuals and found a significant difference in protein expression between normal and cancer samples. More recently, antibody arrays have helped determine specific allergy-related serum proteins whose levels are associated with glioma and can reduce the risk years before diagnosis. Protein profiling with antibody arrays have also proven successful in areas other than cancer research, specifically in neurological diseases such as Alzheimer's. A number of studies have attempted to identify biomarker panels that can distinguish Alzheimer's patients, and many have used antibody arrays in this process. Jaeger and colleagues measured nearly 600 circulatory proteins to discover biological pathways and networks affected in Alzheimer's and explored the positive and negative relationships of the levels of those individual proteins and networks with the cognitive performance of Alzheimer's patients. Currently the largest commercially available sandwich-based antibody array detects 1000 different proteins. In addition, antibody microarray based protein profiling services are available analyzing protein abundance and protein phosphorylation or ubiquitinylation status of 1030 proteins in parallel. | https://en.wikipedia.org/wiki?curid=5655436 | 1,758,460 |
164,421 | The primary winding has relatively few turns of heavy wire. The secondary winding consists of thousands of turns of smaller wire, insulated from the high voltage by enamel on the wires and layers of oiled paper insulation. The coil is usually inserted into a metal can or plastic case with insulated terminals for the high voltage and low voltage connections. When the contact breaker closes, it allows current from the battery to flow through the primary winding of the ignition coil. The current does not flow instantly because of the inductance of the coil. Current flowing in the coil produces a magnetic field in the core and in the air surrounding the core. The current must flow long enough to store enough energy in the field for the spark. Once the current has built up to its full level, the contact breaker opens. Since it has a capacitor connected across it, the primary winding and the capacitor form a tuned circuit, and as the stored energy oscillates between the inductor formed by the coil and the capacitor, the changing magnetic field in the core of the coil induces a much larger voltage in the secondary of the coil. More modern electronic ignition systems operate on exactly the same principle, but some rely on charging the capacitor to around 400 volts rather than charging the inductance of the coil. The timing of the opening of the contacts (or switching of the transistor) must be matched to the position of the piston in the cylinder so that the spark may be timed to ignite the air/fuel mixture to extract the most angular momentum possible. This is usually several degrees before the piston reaches top dead center. The contacts are driven off a shaft that is driven by the engine camshaft, or, if electronic ignition is used, a sensor on the engine shaft controls the timing of the pulses. | https://en.wikipedia.org/wiki?curid=2015982 | 164,336 |
1,602,051 | Kumar resumed his studies in 1968 by enrolling for doctoral studies at the Indian Institute of Technology, Bombay and secured a PhD under the guidance of Krityunjai Prasad Sinha and Ram Prakash Singh in 1971. After doing his post-doctoral work at the laboratory of Maurice Pryce of University of British Columbia, he joined Indian Institute of Science as an assistant professor and served the institution for close to quarter of a century during which period, he held the position of a professor from 1975 to 1994. Kumar was appointed as the director of Raman Research Institute (RRI) in 1994 where he served until his superannuation in 2005. Post-retirement, he continued his association with RRI as the Homi Bhabha Distinguished Scientist and DAE chair professor. During his career, he has had visiting assignments at various institutions abroad such as University of Liège (1975–76), University of Warwick (1978–79), Drexel University (1984), National Autonomous University of Mexico (1985), McGill University (1987 and 1988) and International Centre for Theoretical Physics (1988–89). Kumar was also associated with Jawaharlal Nehru Centre for Advanced Scientific Research, a multidisciplinary research institute, where he held an honorary professor position and with Tata Institute of Fundamental Research as an adjunct professor since 2008. | https://en.wikipedia.org/wiki?curid=53973897 | 1,601,150 |
109,911 | In 1906, Planck acknowledged that his imaginary resonators, having linear dynamics, did not provide a physical explanation for energy transduction between frequencies. Present-day physics explains the transduction between frequencies in the presence of atoms by their quantum excitability, following Einstein. Planck believed that in a cavity with perfectly reflecting walls and with no matter present, the electromagnetic field cannot exchange energy between frequency components. This is because of the linearity of Maxwell's equations. Present-day quantum field theory predicts that, in the absence of matter, the electromagnetic field obeys nonlinear equations and in that sense does self-interact. Such interaction in the absence of matter has not yet been directly measured because it would require very high intensities and very sensitive and low-noise detectors, which are still in the process of being constructed. Planck believed that a field with no interactions neither obeys nor violates the classical principle of equipartition of energy, and instead remains exactly as it was when introduced, rather than evolving into a black body field. Thus, the linearity of his mechanical assumptions precluded Planck from having a mechanical explanation of the maximization of the entropy of the thermodynamic equilibrium thermal radiation field. This is why he had to resort to Boltzmann's probabilistic arguments. | https://en.wikipedia.org/wiki?curid=191123 | 109,866 |
1,814,620 | Prezygotic intrinsic and extrinsic differences have also been shown to be important in isolating hybrids from their parent species. In plants, pollinator mediated isolation resulting from changes in floral characteristics may be an important extrinsic prezygotic ecological barrier. Strong extrinsic pre-zygotic has been shown to isolate the hybrid species "Senecio eboracensis" from its parent species, where hybrids are virtually absent in the wild, although a fraction of hybrid offspring are fertile in lab experiments. Lowe & Abbott conclude that selfing, timing of flowering and characters involved in pollinator attraction likely contribute to this external isolation. Prezygotic mate preference driven isolation generated from intrinsic assortative mating between hybrids has also been reported in several taxa. In African cichlid fish, experimental hybrids displayed combinations of parental traits and preferences which resulted in hybrids predominantly mating with other hybrids. A similar pattern was found in "Geospiza" Galapagos finches where a specific hybrid song resulted from the transgressive beak morphology, and hybrid "Heliconius" butterflies preferred the hybrid wing patterning over that of both parent species. Intrinsic differences in habitat use or in phenology may result in some degree of reproductive isolation against parent species if mating is time and habitat-specific. For example, the apple host race in "Rhagoletis pomonella" maggot flies evolved after introgression of diapause related genes from Mexican altiplano flies that allowed a switch from the ancestral host hawthorne to the later flowering apple and isolated the two host races via allochronic intrinsic pre-zygotic isolation. In "Xiphophorus" swordtail fish strong ancestry assortative mating maintained a hybrid genetic cluster separate for 25 generations, but disappeared under manipulated conditions. Hence, prezygotic reproductive barriers to gene flow may be environment dependent. | https://en.wikipedia.org/wiki?curid=62451338 | 1,813,586 |
1,916,700 | The final started out quickly with the fastest qualifier Natalya Yevdokimova taking an insurmountable lead for the Russians alongside her teammates Olga Yegorova and reigning world champion Tatyana Tomashova. Great Britain's Kelly Holmes, who had earlier won the gold medal in the 800 metres, was expected to challenge her Russian rivals and the rest of the field for a possible Olympic double. Throughout the race, Holmes stayed calmly at the back of the field, lying eighth at the bell. With only one more lap to go, she bided her time to pull away from the rest of the runners through the curve, keeping an eye on the leaders. Holmes made a wider move with only 100 metres remaining to pass the leader Tomashova and sprinted down the home stretch to take the gold medal, setting a new British record of 3:57.90. Tomashova closed the race quickly to get the silver, while Romania's Maria Cioncan could not reach further to chase the leaders on a tight sprint finish, ending her up with a bronze. | https://en.wikipedia.org/wiki?curid=913286 | 1,915,601 |
1,533,855 | Before AC electric generators and the newly invented transformers were invented only DC electrical generators could be used to generate electrical power and they were restricted by their low voltage requirements to economically transmitting power for only a few miles. Too much power was lost in transmission at low voltage for long-distance power transmission to be practical. This meant the original power stations were restricted (at that time) to local steam generating plants built right in each local neighborhood. Pearl Street Station was the first central power plant in the United States. It was located at 255-257 Pearl Street in downtown Manhattan on a site measuring 50 by 100 feet (15 by 30 m), just south of Fulton Street. It began with one direct current generator powered by a coal burning steam engine, and it started generating electricity on September 4, 1882, serving an initial load of 400 incandescent lamps used by 85 customers located within about of the station. | https://en.wikipedia.org/wiki?curid=4242811 | 1,532,987 |
1,718,180 | Climate change may lead to dramatic increases in prevalence of a variety of infectious diseases. Beginning in the mid-'70s, there has been an "emergence, resurgence and redistribution of infectious diseases". Reasons for this are likely multi-causal, dependent on a variety of social, environmental and climatic factors, however, many argue that the "volatility of infectious disease may be one of the earliest biological expressions of climate instability". Though many infectious diseases are affected by changes in climate, vector-borne diseases, such as malaria, dengue fever and leishmaniasis, present the strongest causal relationship. One major reason that change in climate increases the prevalence of vector borne disease is that temperature and rainfall play a key role in the distribution, magnitude, and viral capacity of mosquitoes, who are primary vectors for many vector borne diseases. Observation and research detect a shift of pests and pathogens in the distribution away from the equator and towards Earth's poles. A tool that has been used to predict this distribution trend is the Dynamic Mosquito Simulation Process (DyMSiM). DyMSiM uses epidemiological and entomological data and practices to model future mosquito distributions based upon climate conditions and mosquitos living in the area. This modeling technique helps identify the distribution of specific species of mosquito, some of which are more susceptible to viral infection than others. | https://en.wikipedia.org/wiki?curid=63453251 | 1,717,210 |
1,764,595 | After the creation of the first nine Suvorov schools in the early 1940s, the State Defense Committee adopted a resolution of June 4, 1944 to organize an additional six schools, including Kazan. On June 20, 1944, the Commander of the Volga Military District issued a directive on the formation of the Kazan Suvorov Military School. The temporary formation point was in the Admiralty suburb of Kazan, on the territory of the Zhytomyr Military Infantry School. The academic building was completed on September 30, 1944, which would later hold four companies of 100 people each. The first bell rang on October 2, 1944, with the first set of boys representing 14 nationalities from 19 regions and 8 autonomous republics of the center of the country. In 1949, 5 years later, the school's first graduation parade was held, when its first graduating classes were presented diplomas for completing secondary education. In 1973, the school was awarded by the Military Council of the Volga Military District for its success in the military-patriotic education of its students with the prestigious Order of the Red Banner, in celebration of the 30th anniversary of the Suvorov Schools. The school has also repeatedly won the Honor Prize of the Ministry of Defence of the Russian Federation, and has received a certificate of merit by the Commander-in-Chief of the Russian Ground Forces. | https://en.wikipedia.org/wiki?curid=59490780 | 1,763,602 |
629,678 | On March 18, 1959, the USAF told the BMEWS Project Office to proceed with an interim facility for the "AICBM control center" with an anti-ICBM C computer (e.g., for when the USAF Wizard and/or Army Nike Zeus ABMs became operational), and the basement of the 1954 ADC blockhouse was considered for the interim center. A "satellite prediction computer" could be added to the planned missile warning center if Cheyenne Mountain's "hardened COC slipped considerably beyond January 1962" (tunneling began in June 1961.) In early 1959 for use at Ent in September 1960, a BMEWS display facility with "austere and economical construction with minimum equipment" was planned in an "annex to the current COC building". In late 1959, ARPA opened the 474L System Program Office, and BMEWS' "12th Missile Warning Squadron at Thule...began operating in January 1960." Following a Nike ABM intercept of a test missile, the planned Cheyenne Mountain mission was expanded in August 1960 to "a hardened center from which CINCNORAD would supervise and direct operations against space attack as well as air attack" (NORAD assumed "operational control of all space assets with the formation of" SPADATS in October 1960.) The 1st Aerospace Surveillance and Control Squadron (1st Aero) was activated at Ent AFB on February 14, 1961; and Ent's Federal Building was completed . | https://en.wikipedia.org/wiki?curid=736540 | 629,340 |
1,364,660 | "Phronima sedentaria" most commonly exhibits a symbiotic relationship with tunicates of the genera "Pyrosoma spp.", "Doliolum spp.", and "Salpa" "spp". It is not entirely certain how to classify the symbiotic relationship between "P. sedentaria" and its hosts, as instances of commensalism, parasitism, and predation have all been observed. However, some research has suggested that the majority of suborder Hyperiidea members exhibit parasitic behavior. Females of "P. sedentaria" live in the barrel-like bodies of salps, pyrosomes, and cnidarians, and use their strong pleopods to propel their homes through the water. They can somersault rapidly in their barrels, thus quickly changing direction. However, speed is reduced by a factor of three to four when swimming while inside a barrel compared to swimming without one. The shape of the barrel is generally asymmetrical, with one opening three times larger than that of the other. In order to construct their barrels, females first locate a suitable salp, pyrosome, or cnidarian host and either cut into the host or enter through an existing opening. Once inside, the female consumes the organism within and carve out the gelatinous inside, leaving nothing but the tunic. The cells on the tunic layer may serve various functions for the "P. sedentaria," including protection from UV light, storage of acid, and defense against microorganisms, like bacteria. In laboratory experiments with restricted access to potential hosts, females have additionally displayed competition for barrels. | https://en.wikipedia.org/wiki?curid=14166896 | 1,363,904 |
1,474,171 | The Benton Test is sensitive to many forms of brain impairments and diseases, but it is difficult to diagnose a particular disease through the test. In fact, according to the test manual, a high number of a single category of error should not be used as a diagnosis, but should lead to further testing. High amounts of perseverations, for example, suggests frontal lobe damage, while the omission of peripheral designs suggests potential brain trauma, especially in the right parietal lobe. Overall performance does not seem to distinguish those with unilateral left or right hemisphere damage. Nevertheless, examiners have shown to be able to discriminate among perceptual, memory, and motor impairments based on analysis of the test results. Dementia, brain lesions, thalamic stroke, and Alzheimer's disease are among the conditions that have been shown to greatly reduce an individual's BVRT score. Both the copy and memory versions of the test are especially sensitive to dementia, and may help identify individuals who are at risk for developing Alzheimer's later. In addition, learning disabilities among children are able to be identified through the Benton Test. In 1983, the Benton Test was included in the Neurobehavioral Core Test Battery (NCTB) to identify the effects of chemical exposure on the nervous system and has since been used to assess chemical exposure in the workplace. From its use in the NCTB, the Benton Test has shown sensitivity to various chemical exposures, including mercury exposure, lead exposure, and pesticide exposure. | https://en.wikipedia.org/wiki?curid=10174708 | 1,473,340 |
1,020,137 | According to the astrobiologists Peter Ward and Donald Brownlee in their book "The Life and Death of Planet Earth", the current loss rate is approximately one millimeter of ocean per million years, but the rate is gradually accelerating, as the sun gets warmer, to perhaps as fast as one millimeter every 1000 years. Ward and Brownlee predict that there will be two variations of the future warming feedback: the "moist greenhouse" in which water vapor dominates the troposphere and starts to accumulate in the stratosphere and the "runaway greenhouse" in which water vapor becomes a dominant component of the atmosphere such that the Earth starts to undergo rapid warming, which could send its surface temperature to over , causing its entire surface to melt and killing all life, perhaps about three billion years from now. In both cases, the moist and runaway greenhouse states the loss of oceans will turn the Earth into a primarily-desert world. The only water left on the planet would be in a few evaporating ponds scattered near the poles as well as huge salt flats around what was once the ocean floor, much like the Atacama Desert in Chile or Badwater Basin in Death Valley. The small reservoirs of water may allow life to remain for a few billion more years. | https://en.wikipedia.org/wiki?curid=3459279 | 1,019,610 |
511,826 | Pancreatic exocrine insufficiency may be treated through pancreatic enzyme supplementation, while severe skeletal abnormalities may require surgical intervention. Neutropenia may be treated with granulocyte-colony stimulating factor (GCSF) to boost peripheral neutrophil counts. However, there is ongoing and unresolved concern that this drug could contribute to the development of leukemia. Signs of progressive marrow failure may warrant bone marrow transplantation (BMT). This has been used successfully to treat hematological aspects of disease. However, SDS patients have an elevated occurrence of BMT-related adverse events, including graft-versus-host disease (GVHD) and toxicity relating to the pre-transplant conditioning regimen. In the long run, study of the gene that is mutated in SDS should improve understanding of the molecular basis of disease. This, in turn, may lead to novel therapeutic strategies, including gene therapy and other gene- or protein-based approaches. | https://en.wikipedia.org/wiki?curid=25715899 | 511,560 |
1,771,976 | Results from Viking lander experiments strongly suggest the presence of water in the present and in the past of Mars. All samples heated in the gas chromatograph-mass spectrometer (GSMS) gave off water. However, the way the samples were handled prohibited an exact measurement of the amount of water. But, it was around 1%. General chemical analysis suggested the surface had been exposed to water in the past. Some chemicals in the soil contained sulfur and chlorine that were like those remaining after sea water evaporates. Sulfur was more concentrated in the crust on top of the soil, than in the bulk soil beneath. So it was concluded that the upper crust was cemented together with sulfates that were transported to the surface dissolved in water. This process is common on Earth's deserts. The sulfur may be present as sulfates of sodium, magnesium, calcium, or iron. A sulfide of iron is also possible. Using results from the chemical measurements, mineral models suggest that the soil could be a mixture of about 90% iron-rich clay, about 10% magnesium sulfate (kieserite?), about 5% carbonate (calcite), and about 5% iron oxides (hematite, magnetite, goethite?). These minerals are typical weathering products of mafic igneous rocks. The presence of clay, magnesium sulfate, kieserite, calcite, hematite, and goethite strongly suggest that water was once in the area. Sulfate contains chemically bound water, hence its presence suggests water was around in the past. Viking 2 found similar group of minerals. Because Viking 2 was much farther north, pictures it took in the winter showed frost. | https://en.wikipedia.org/wiki?curid=32939362 | 1,770,979 |
1,301,365 | The word allotype comes from two Greek roots, "allo" meaning 'other or differing from the norm' and "typos" meaning 'mark'. In immunology, allotype is an immunoglobulin variation (in addition to isotypic variation) that can be found among antibody classes and is manifested by heterogeneity of immunoglobulins present in a single vertebrate species. The structure of immunoglobulin polypeptide chain is dictated and controlled by number of genes encoded in the germ line. However, these genes, as it was discovered by serologic and chemical methods, could be highly polymorphic. This polymorphism is subsequently projected to the overall amino acid structure of antibody chains. Polymorphic epitopes can be present on immunoglobulin constant regions on both heavy and light chains, differing between individuals or ethnic groups and in some cases may pose as immunogenic determinants. Exposure of individuals to a non-self allotype might elicit an anti- allotype response and became cause of problems for example in a patient after transfusion of blood or in a pregnant woman. However, it is important to mention that not all variations in immunoglobulin amino acid sequence pose as a determinant responsible for immune response. Some of these allotypic determinants may be present at places that are not well exposed and therefore can be hardly serologically discriminated. In other cases, variation in one isotype can be compensated by the presence of this determinant on another antibody isotype in one individual. This means that divergent allotype of heavy chain of IgG antibody may be balanced by presence of this allotype on heavy chain of for example IgA antibody and therefore is called isoallotypic variant. Especially large number of polymorphisms were discovered in IgG antibody subclasses. Which were practically used in forensic medicine and in paternity testing, before replaced by modern day DNA fingerprinting. | https://en.wikipedia.org/wiki?curid=10807783 | 1,300,651 |
1,610,893 | The Abell Catalog of Planetary Nebulae was created in 1966 by George O. Abell and was composed of 86 entries thought to be planetary nebulae that were collected from discoveries, about half by Albert George Wilson and the rest by Abell, Robert George Harrington, and Rudolph Minkowski. All were discovered before August 1955 as part of the National Geographic Society – Palomar Observatory Sky Survey on photographic plates created with the Samuel Oschin telescope at Mount Palomar. Four are better known from previous catalogs: Abell 50 is NGC 6742, Abell 75 is NGC 7076, Abell 37 is IC 972, and Abell 81 is IC 1454. Another four were later rejected as not being planetaries: Abell 11 (reflection nebula), Abell 32 (red plate flaw), Abell 76 (ring galaxy PGC 85185), and Abell 85 (supernova remnant CTB 1 and noted as possibly such in Abell's 1966 paper). Another three were also not included in the Strasbourg-ESO Catalogue of Galactic Planetary Nebulae (SEC): Abell 9, Abell 17 (red plate flaw), and Abell 64. Planetaries on the list are best viewed with a large aperture telescope (e.g. ) and an OIII filter. | https://en.wikipedia.org/wiki?curid=43475307 | 1,609,988 |
981,083 | Anthropology grew increasingly distinct from natural history and by the end of the 19th century the discipline began to crystallize into its modern form—by 1935, for example, it was possible for T. K. Penniman to write a history of the discipline entitled "A Hundred Years of Anthropology". At the time, the field was dominated by "the comparative method". It was assumed that all societies passed through a single evolutionary process from the most primitive to most advanced. Non-European societies were thus seen as evolutionary "living fossils" that could be studied in order to understand the European past. Scholars wrote histories of prehistoric migrations which were sometimes valuable but often also fanciful. It was during this time that Europeans first accurately traced Polynesian migrations across the Pacific Ocean for instance—although some of them believed it originated in Egypt. Finally, the concept of race was actively discussed as a way to classify—and rank—human beings based on difference. | https://en.wikipedia.org/wiki?curid=33661613 | 980,571 |
1,599,192 | The organization moved back to Grand Rapids in December 2010 a facility situated on Leonard Street NW, dubbed The Leonard Street Labs. On January 2, 2014, a fire partially destroyed the organization's High Voltage Lab, and deposited soot all over the lab. A grub screw on a Tesla coil rotary spark gap was not tight enough, allowing a tungsten electrode to move out of its socket and strike one of the stationary electrodes. This resulted in a chain reaction with molten tungsten being flung from the spark gap unit, which caused a nearby capacitor array to catch fire and subsequently melt. From preliminary analysis, Project Gemini (a 200,000 watt Tesla coil demonstration) looks to be the originating cause, and completely destroyed, and Project Thumper (a high impulse generator) was damaged. The fire was so hot it melted aluminum racks. Although no one had been hurt, the building was closed to the public once again for repairs. | https://en.wikipedia.org/wiki?curid=33814610 | 1,598,292 |
1,668,441 | Assumptions regarding the undeformed burrow and its geometric relationship cannot directly be determined, and only estimated. While it is common for "Skolithos" burrows to form normal to the deposition plane, this is not always true, in which case, the ideal, undeformed state can no longer be used as a reference orientation. Shallow depositional sediments are also susceptible to damage by erosion and tectonic stress forces, which can influence average measurements and geometric orientations. Since the rheological properties between the structure and the host rock are usually very similar, observations of the fossils are conducted with the assumption that they have deformed homogeneously, where the deformation forces are distributed evenly along the entire deformation zone. This is directly contradicted by the presence of folding and varying elongation measurements of the fossil at different locations in the same deformation zone. Deformation mechanisms are difficult to distinguish using this strain marker, as the thinning and flattening of the highly deformed rocks where they are found, cannot necessarily be attributed to pure shear since the planes may have simply rotated near parallel to the shear plane. It is therefore only possible to make accurate strain determinations of the host rock provided the correct assumption of the deformation mechanism and original measurements. | https://en.wikipedia.org/wiki?curid=17037490 | 1,667,502 |
1,242,844 | Anionic surfactants such as sodium dodecyl sulfate are most commonly used for stabilizing emulsions because of their affinity for hydrogen bonding with the aqueous medium. Nonionic surfactants are rarely used alone due to their inferior efficiency in creating stable emulsions in comparison to anionic surfactants. Because of this, non-ionic surfactants are usually used in tandem with anionic surfactants and impart a second method of colloidal stabilization through steric interference of the van der Waals forces amid polymer and pigment particles. Latexes that require stability over large pH ranges use larger nonionic to anionic surfactant ratios. Cationic surfactants are least commonly used because of their high cost, inefficient emulsifying capability, and undesirable effects on initiator decomposition. High speed application, low temperature storage, shear stresses from pumping, and other extreme storage or application conditions can cause the failure of a surfactant to adequately stabilize a paint dispersion. | https://en.wikipedia.org/wiki?curid=32001021 | 1,242,171 |
623,766 | In the early 11th century, Ibn al-Haytham (Alhazen) wrote the "Maqala fi daw al-qamar" ("On the Light of the Moon") some time before 1021. This was the first attempt successful at combining mathematical astronomy with physics and the earliest attempt at applying the experimental method to astronomy and astrophysics. He disproved the universally held opinion that the moon reflects sunlight like a mirror and correctly concluded that it "emits light from those portions of its surface which the sun's light strikes." In order to prove that "light is emitted from every point of the moon's illuminated surface," he built an "ingenious experimental device." Ibn al-Haytham had "formulated a clear conception of the relationship between an ideal mathematical model and the complex of observable phenomena; in particular, he was the first to make a systematic use of the method of varying the experimental conditions in a constant and uniform manner, in an experiment showing that the intensity of the light-spot formed by the projection of the moonlight through two small apertures onto a screen diminishes constantly as one of the apertures is gradually blocked up." | https://en.wikipedia.org/wiki?curid=6012554 | 623,434 |
411,847 | Robert Koch made two important developments in microscopy; he was the first to use an oil immersion lens and a condenser that enabled smaller objects to be seen. In addition, he was also the first to effectively use photography (microphotography) for microscopic observation. He introduced the "bedrock methods" of bacterial staining using methylene blue and Bismarck (Vesuvin) brown dye. In an attempt to grow bacteria, Koch began to use solid nutrients such as potato slices. Through these initial experiments, Koch observed individual colonies of identical, pure cells. He found that potato slices were not suitable media for all organisms, and later began to use nutrient solutions with gelatin. However, he soon realized that gelatin, like potato slices, was not the optimal medium for bacterial growth, as it did not remain solid at 37 °C, the ideal temperature for growth of most human pathogens. And also many bacteria can hydrolyze gelatin making it a liquid. As suggested to him by his post-doctoral assistant Walther Hesse, who got the idea from his wife Fanny Hesse, in 1881, Koch started using agar to grow and isolate pure cultures. Agar is a polysaccharide that remains solid at 37 °C, is not degraded by most bacteria, and results in a stable transparent medium. | https://en.wikipedia.org/wiki?curid=13722 | 411,645 |
1,077,284 | For ICs, SI analysis became necessary as an effect of reduced design rules. In the early days of the modern VLSI era, digital chip circuit design and layout were manual processes. The use of abstraction and the application of automatic synthesis techniques have since allowed designers to express their designs using high-level languages and apply an automated design process to create very complex designs, ignoring the electrical characteristics of the underlying circuits to a large degree. However, scaling trends (see Moore's law) brought electrical effects back to the forefront in recent technology nodes. With scaling of technology below 0.25 µm, the wire delays have become comparable or even greater than the gate delays. As a result, the wire delays needed to be considered to achieve timing closure. In nanometer technologies at 0.13 µm and below, unintended interactions between signals (e.g. crosstalk) became an important consideration for digital design. At these technology nodes, the performance and correctness of a design cannot be assured without considering noise effects. | https://en.wikipedia.org/wiki?curid=3492525 | 1,076,729 |
313,508 | The physiological blood-flow response largely decides the temporal sensitivity, that is how accurately we can measure when neurons are active, in BOLD fMRI. The basic time resolution parameter (sampling time) is designated TR; the TR dictates how often a particular brain slice is excited and allowed to lose its magnetization. TRs could vary from the very short (500 ms) to the very long (3 s). For fMRI specifically, the hemodynamic response lasts over 10 seconds, rising multiplicatively (that is, as a proportion of current value), peaking at 4 to 6 seconds, and then falling multiplicatively. Changes in the blood-flow system, the vascular system, integrate responses to neuronal activity over time. Because this response is a smooth continuous function, sampling with ever-faster TRs does not help; it just gives more points on the response curve obtainable by simple linear interpolation anyway. Experimental paradigms such as staggering when a stimulus is presented at various trials can improve temporal resolution, but reduces the number of effective data points obtained. | https://en.wikipedia.org/wiki?curid=226722 | 313,339 |
2,156,612 | Each of the wind tunnels at "LFA" was given an "A" number. A1 had a circular nozzle in diameter, producing a maximum speed of ; it entered service in 1937, the year after construction began on facilities. A2 measured long and had a test section in diameter (coated with Keratylene to keep the flow smooth), capable of generating test speeds (depending on the model's scale) of between Mach 1 and 1.2. It was driven by a pair of DC motors, and fitted with interferometer and striation gear for study of flow patterns. Begun in 1937, it first ran in 1939. It did, however, suffer with problems of vibration, leading the research teams to rely on a Rheinmetall-Börsig F25 free-flight research rocket with models mounted in the nose. The A3 tunnel, largest at the "LFA" site, had an test section with a maximum speed of and a working length of , enough to accommodate a Messerschmitt Bf 109's fuselage. It was powered by a pair of . The A9 building housed a pair of supersonic wind tunnels, each driven by a motor, with a maximum speed of Mach 1.5, but a test section diameter of only . | https://en.wikipedia.org/wiki?curid=42845378 | 2,155,381 |
440,205 | At the start of the Federalist Era, New York City was the nation's capital, but the Constitution had provided for the establishment of a permanent national capital under federal authority. Article One of the Constitution permits the establishment of a "District (not exceeding ten miles square) as may, by cession of particular states, and the acceptance of Congress, become the seat of the government of the United States". In what is now known as the Compromise of 1790, Madison, Alexander Hamilton, and Thomas Jefferson came to an agreement that the federal government would pay each state's remaining Revolutionary War debts in exchange for establishing the new national capital in the Southern United States. In July 1790, Congress passed the Residence Act, which approved the creation of a national capital on the Potomac River. The exact location was to be selected by President George Washington. Maryland and Virginia donated land to the federal government that collectively formed a square measuring on each side. The Residence Act also established Philadelphia as the federal capital until the government moved to the federal district. Congress adjourned its last meeting in Philadelphia on May 15, 1800, and the city officially ceased to be the nation's seat of government as of June 1800. President John Adams moved into the White House later that year. | https://en.wikipedia.org/wiki?curid=16829738 | 439,991 |
5,502 | The head of the legal system was officially the pharaoh, who was responsible for enacting laws, delivering justice, and maintaining law and order, a concept the ancient Egyptians referred to as Ma'at. Although no legal codes from ancient Egypt survive, court documents show that Egyptian law was based on a common-sense view of right and wrong that emphasized reaching agreements and resolving conflicts rather than strictly adhering to a complicated set of statutes. Local councils of elders, known as "Kenbet" in the New Kingdom, were responsible for ruling in court cases involving small claims and minor disputes. More serious cases involving murder, major land transactions, and tomb robbery were referred to the "Great Kenbet", over which the vizier or pharaoh presided. Plaintiffs and defendants were expected to represent themselves and were required to swear an oath that they had told the truth. In some cases, the state took on both the role of prosecutor and judge, and it could torture the accused with beatings to obtain a confession and the names of any co-conspirators. Whether the charges were trivial or serious, court scribes documented the complaint, testimony, and verdict of the case for future reference. | https://en.wikipedia.org/wiki?curid=874 | 5,499 |
595,763 | A variety of issues degrade the quality of HPIV results. The first class of issues involves the reconstruction itself. In holography, the object wave of a particle is typically assumed to be spherical; however, due to Mie scattering theory, this wave is a complex shape which can distort the reconstructed particle. Another issue is the presence of substantial speckle noise which lowers the overall signal-to-noise ratio of particle images. This effect is of greater concern for in-line holographic systems because the reference beam is propagated through the volume along with the scattered object beam. Noise can also be introduced through impurities in the scattering medium, such as temperature variations and window blemishes. Because holography requires coherent imaging, these effects are much more severe than traditional imaging conditions. The combination of these factors increases the complexity of the correlation process. In particular, the speckle noise in an HPIV recording often prevents traditional image-based correlation methods from being used. Instead, single particle identification and correlation are implemented, which set limits on particle number density. A more comprehensive outline of these error sources is given in Meng et al. | https://en.wikipedia.org/wiki?curid=1058299 | 595,458 |
1,256,220 | A parallel beam emerges through a side port of the interferometer which passes first through a wire grid linear polarizer and then through an octagonal-shaped ZnSe crystal PEM which modulates the polarized beam at a fixed, lower frequency such as 37.5 kHz. A mechanically stressed crystal such as ZnSe exhibits birefringence when stressed by an adjacent piezoelectric transducer. The linear polarizer is positioned close to, and at 45 degrees, with respect to the ZnSe crystal axis. The polarized radiation focused onto the detector is doubly modulated, both by the PEM and by the interferometer setup. A very low noise detector, such as MCT (HgCdTe), is also selected for the VCD signal phase-sensitive detection. The first dedicated VCD spectrometer brought to market was the ChiralIR from Bomem/BioTools, Inc. in 1997. Today, Thermo-Electron, Bruker, Jasco and BioTools offer either VCD accessories or stand-alone instrumentation. To prevent detector saturation an appropriate, long wave pass filter is placed before the very low noise MCT detector, which allows only radiation below 1750 cm to reach the MCT detector; the latter however measures radiation only down to 750 cm. FT-VCD spectra accumulation of the selected sample solution is then carried out, digitized and stored by an in-line computer. Published reviews that compare various VCD methods are also available. | https://en.wikipedia.org/wiki?curid=9233359 | 1,255,536 |
71,167 | Mustard gases' blistering effects can be neutralized by oxidation or chlorination, using household bleach (sodium hypochlorite), or by nucleophilic attack using decontamination solutions such as "DS2" (2% NaOH, 70% diethylenetriamine, 28% 2-methoxyethanol). After initial decontamination of the victim's wounds is complete, medical treatment is similar to that required by any conventional burn. The degree of pain and discomfort suffered by the victim is also comparable. Mustard agent burns do not heal quickly, and (as with other types of burns) present a risk of sepsis caused by pathogens such as "Staphylococcus aureus" and "Pseudomonas aeruginosa". The mechanisms behind mustard gas's effect on endothelial cells are still being studied, but recent studies have shown that high levels of exposure can induce high rates of both necrosis and apoptosis. In vitro tests have shown that at low concentrations of mustard gas, where apoptosis is the predominant result of exposure, pretreatment with 50 mM N-acetyl-L-cysteine (NAC) was able to decrease the rate of apoptosis. NAC protects actin filaments from reorganization by mustard gas, demonstrating that actin filaments play a large role in the severe burns observed in victims. | https://en.wikipedia.org/wiki?curid=46126 | 71,140 |
842,286 | This judicial ruling meant that Lee de Forest was now legally recognized in the United States as the inventor of regeneration. However, much of the engineering community continued to consider Armstrong to be the actual developer, with de Forest viewed as someone who skillfully used the patent system to get credit for an invention to which he had barely contributed. Following the 1934 Supreme Court decision, Armstrong attempted to return his Institute of Radio Engineers (present-day Institute of Electrical and Electronics Engineers) Medal of Honor, which had been awarded to him in 1917 "in recognition of his work and publications dealing with the action of the oscillating and non-oscillating audion", but the organization's board refused to let him, stating that it "strongly affirms the original award". The practical effect of de Forest's victory was that his company was free to sell products that used regeneration, for during the controversy, which became more a personal feud than a business dispute, Armstrong tried to block the company from even being licensed to sell equipment under his patent. | https://en.wikipedia.org/wiki?curid=256764 | 841,836 |
1,356,242 | Due to this orchid mycorrhiza in general are considered at least partially mycoheterotrophic interactions. In the mycoheterotrophic orchid mycorrhiza carbon is taken up, by the fungi, as an array of peptide and carbohydrate species often the products of saprophytic reactions taking place in the soil. These reactions are often instigated and progressed by the activity of the mycorrhizal fungus, being part of the basidiomycete phyla, orchid associated fungi have an extensive metabolic arsenal with which to pull from, and are readily able to digest cellulose and lignin to obtain the carbon. Genes encoding proteases, cellulose and lignin digestive enzymes, as well as oligopeptide and carbohydrate transporters are upregulated in the mycelial soil webs to facilitate increased carbon uptake. Further more the fungi which mycoheterotrophically interact with orchid plants are often also found in mycorrhizal association with beech trees, and translocation of photosynthate from tree to fungus and then to orchid has been proposed, but a thorough study is still lacking. Once acquired by the fungus the carbon is either converted into sugars, trehalose being extremely common for most mycorrhizal fungus, amino acids, or simply assimilated into the fungal organism. The transfer of carbon from fungi to plant happens in one of two forms either as carbohydrates primarily trehalose, but glucose and sucrose may also be involved, or as an amino acids primarily as arginine but glycine and glutamine can also be transferred. These molecules are transported, via specialized amino acid permeases and carbohydrate transporters embedded in the fungal peloton membrane, into the interficial space where they are absorbed into the plant through similar analogous transporters in the plant endoplasmic reticulum membrane which surrounds the peloton. Genes which encode for such transporters experience significant upregulation in both plant and fungi, similar to the upregulation seen in nitrogen and phosphorus compound transporter genes during symbiosis. This active transport of carbon from fungi to plant is an exclusively biotrophic reaction but it is thought that a significant amount of carbon may also be transferred to the plant when the fungal pelotons degrade and are digested. | https://en.wikipedia.org/wiki?curid=55484311 | 1,355,493 |
248,126 | The Nuclear Structure Facility (NSF) at Daresbury Laboratory was proposed in the 1970s, commissioned in 1981, and opened for experiments in 1983. It consisted of a tandem Van de Graaff generator operating routinely at 20 MV, housed in a distinctive building 70 m high. During its lifetime, it accelerated 80 different ion beams for experimental use, ranging from protons to uranium. A particular feature was the ability to accelerate rare isotopic and radioactive beams. Perhaps the most important discovery made using the NSF was that of super-deformed nuclei. These nuclei, when formed from the fusion of lighter elements, rotate very rapidly. The pattern of gamma rays emitted as they slow down provided detailed information about the inner structure of the nucleus. Following financial cutbacks, the NSF closed in 1993. | https://en.wikipedia.org/wiki?curid=52642 | 247,998 |
1,736,664 | CASTEP is a shared-source academic and commercial software package which uses density functional theory with a plane wave basis set to calculate the electronic properties of crystalline solids, surfaces, molecules, liquids and amorphous materials from first principles. CASTEP permits geometry optimisation and finite temperature molecular dynamics with implicit symmetry and geometry constraints, as well as calculation of a wide variety of derived properties of the electronic configuration. Although CASTEP was originally a serial, Fortran 77-based program, it was completely redesigned and rewritten from 1999 to 2001 using Fortran 95 and MPI for use on parallel computers by researchers at the Universities of York, Durham, St. Andrews, Cambridge and Rutherford Labs. | https://en.wikipedia.org/wiki?curid=2437021 | 1,735,687 |
758,816 | The Kuramoto model of coupled phase oscillators is one of the most abstract and fundamental models used to investigate neural oscillations and synchronization. It captures the activity of a local system (e.g., a single neuron or neural ensemble) by its circular phase alone and hence ignores the amplitude of oscillations (amplitude is constant). Interactions amongst these oscillators are introduced by a simple algebraic form (such as a sine function) and collectively generate a dynamical pattern at the global scale. The Kuramoto model is widely used to study oscillatory brain activity and several extensions have been proposed that increase its neurobiological plausibility, for instance by incorporating topological properties of local cortical connectivity. In particular, it describes how the activity of a group of interacting neurons can become synchronized and generate large-scale oscillations. Simulations using the Kuramoto model with realistic long-range cortical connectivity and time-delayed interactions reveal the emergence of slow patterned fluctuations that reproduce resting-state BOLD functional maps, which can be measured using fMRI. | https://en.wikipedia.org/wiki?curid=2860430 | 758,410 |
1,377,986 | The LVDC was approximately wide, high, and deep and weighed . The chassis was made of magnesium-lithium alloy LA 141, chosen for its high stiffness, low weight, and good vibration damping characteristics. The chassis was divided into a 3 x 5 matrix of cells separated by walls through which coolant was circulated to remove the 138 watts of power dissipated by the computer. Slots in the cell walls held "pages" of electronics. The decision to cool the LVDC by circulating coolant through the walls of the computer was unique at the time and allowed the LVDC and LVDA (part-cooled using this technique) to be placed in one cold plate location due to the three dimensional packaging. The cold plates used to cool most equipment in the Instrument Unit were inefficient from a space view although versatile for the variety of equipment used. The alloy LA 141 had been used by IBM on the Gemini keyboard, read out units, and computer in small quantities and the larger frame of the LVDC was produced from the largest billets of LA 141 cast at the time and subsequently CNC machined into the frame. | https://en.wikipedia.org/wiki?curid=5887605 | 1,377,224 |
261,352 | Oliphant took the resulting Frisch–Peierls memorandum to Sir Henry Tizard, the chairman of the Tizard Committee, and the MAUD Committee was established to investigate further. It held its first meeting on 10 April 1940, in the ground-floor main committee room of the Royal Society in Burlington House in London. It directed an intensive research effort, and in July 1941, produced two comprehensive reports that reached the conclusion that an atomic bomb was not only technically feasible, but could be produced before the war ended, perhaps in as little as two years. The Committee unanimously recommended pursuing the development of an atomic bomb as a matter of urgency, although it recognised that the resources required might be beyond those available to Britain. A new directorate known as Tube Alloys was created to coordinate this effort. Sir John Anderson, the Lord President of the Council, became the minister responsible, and Wallace Akers from Imperial Chemical Industries (ICI) was appointed the director of Tube Alloys. | https://en.wikipedia.org/wiki?curid=2095669 | 261,213 |
763,468 | Traditionally, sources of variation have been understood in discrete categories, such as age, height, weight, gender, geographical region (altitude), and race or ethnicity. Global efforts were made in the early twentieth century to standardize these sources to enable proper diagnosis and accurate evaluation of pulmonary function. However, rather than further aiming to understand the causes of such variations, the primary approach for dealing with observed differences in lung capacity has been to "correct for" them. Using results from comparative population studies, attributes are empirically factored together into a "correction factor". This number is then used to form a personalized 'reference value' that defines what is considered normal for one individual. Practitioners may thereby find the percent deviation from this predicted value, known as 'percent of predicted,’ and determine whether someone’s lung function is abnormally poor or excellent. | https://en.wikipedia.org/wiki?curid=482529 | 763,059 |
2,058,903 | In her early research, Silver investigated the hormonal mechanisms of parental behavior in ring doves, which exhibit bi-parental care. Her early studies focused on the neural and hormonal mechanisms of behavior in male ring doves, in particular, as well as the sharing of parental responsibility and coordination between the male and female. She documented a number of changes in both members of the pair across the reproductive cycle, including in steroid hormones, luteinizing hormone, prolactin, vasoactive intestinal peptide (VIP), gonadotropin-releasing hormone (GnRH). Her interest in changes which occurred in the brains of ring doves during reproduction and parental behaviors, such as the timing of egg incubation bouts, led her to pursue questions related to circadian rhythms (daily cycles of activity and sleep). Her and members of her lab then performed a number of fundamental experiments demonstrating on the mechanisms underlying circadian rhythms in both birds and mammals, including a series of experiments demonstrating that a hormonal signal from the SCN sustains circadian activity rhythms in golden hamsters. She has also conducted research on the role of mast cells, part of the immune system, on brain vasculature, hormone production, neuronal transmission, and behavior. Her current research areas focus on sleep-wake cycles and their neural bases, and on immune-nervous system interactions in the brain. | https://en.wikipedia.org/wiki?curid=62979672 | 2,057,718 |
1,192,076 | In 1990s, a new technique called metabolic engineering emerged. This technique analyzes the metabolic pathway of a microorganism, and determines the constraints and their effects on the production of desired compounds. It then uses genetic engineering to relieve these constraints. Some examples of successful metabolic engineering are the following: (i) Identification of constraints to lysine production in "Corynebacterium" "glutamicum" and insertion of new genes to relieve these constraints to improve production (ii) Engineering of a new fatty acid biosynthesis pathway, called reversed beta oxidation pathway, that is more efficient than the native pathway in producing fatty acids and alcohols which can potentially be catalytically converted to chemicals and fuels (iii) Improved production of DAHP an aromatic metabolite produced by "E. coli" that is an intermediate in the production of aromatic amino acids. It was determined through metabolic flux analysis that the theoretical maximal yield of DAHP per glucose molecule utilized, was 3/7. This is because some of the carbon from glucose is lost as carbon dioxide, instead of being utilized to produce DAHP. Also, one of the metabolites (PEP, or phosphoenolpyruvate) that are used to produce DAHP, was being converted to pyruvate (PYR) to transport glucose into the cell, and therefore, was no longer available to produce DAHP. In order to relieve the shortage of PEP and increase yield, Patnaik et al. used genetic engineering on "E. coli" to introduce a reaction that converts PYR back to PEP. Thus, the PEP used to transport glucose into the cell is regenerated, and can be used to make DAHP. This resulted in a new theoretical maximal yield of 6/7 – double that of the native "E. coli" system. | https://en.wikipedia.org/wiki?curid=1585648 | 1,191,440 |
1,495,664 | These principles serve to provide a basic insight into novel mechanical properties of nanometer objects. Novelty is understood in the sense that these properties are not present in similar macroscale objects or much different from the properties of those (e.g., nanorods vs. usual macroscopic beam structures). In particular, smallness of the subject itself gives rise to various surface effects determined by higher surface-to-volume ratio of nanostructures, and thus affects mechanoenergetic and thermal properties (melting point, heat capacitance, etc.) of nanostructures. Discreteness serves a fundamental reason, for instance, for the dispersion of mechanical waves in solids, and some special behavior of basic elastomechanics solutions at small scales. Plurality of degrees of freedom and the rise of thermal fluctuations are the reasons for thermal tunneling of nanoparticles through potential barriers, as well as for the cross-diffusion of liquids and solids. Smallness and thermal fluctuations provide the basic reasons of the Brownian motion of nanoparticles. Increased importance of thermal fluctuations and configuration entropy at the nanoscale give rise to superelasticity, entropic elasticity (entropic forces), and other exotic types of elasticity of nanostructures. Aspects of configuration entropy are also of great interest in the context self-organization and cooperative behavior of open nanosystems. | https://en.wikipedia.org/wiki?curid=14661057 | 1,494,822 |
2,196,656 | The Society for Basic Urologic Research (SBUR) is a US-based basic urological researcher's society with ~600 active members in the US, Europe and Asia, including laboratory and physician scientists (Ph.D.'s, M.D.'s, M.D.-Ph.D.'s, and trainees) in academia, industry and the government. The major research interest areas are normal physiology and pathophysiology of the organs in the genitourinary system including the kidney, the bladder, the prostate, the testis and the penis. The SBUR holds two annual meetings each year. The SBUR Spring meeting in May of each year is part of the American Urological Association's (AUA) annual meeting, on the third Saturday of the month. The SBUR Fall-Winter meeting is the Society's independent research symposium featuring plenary sessions and poster sessions over four days. The SBUR and the European Society for Urological Research (ESUR) alternate to host the World Basic Urological Research Congress every two years on the two continents. Some of the recent topics for discussion at these meetings include hormone-refractory prostate cancer and inflammatory diseases in the prostate such as benign prostatic hyperplasia (BPH), among others. Researchers in the SBUR are actively studying the disease mechanisms and looking for better methods of diagnosing and treating the many urological disorders that compromise the quality of life with aging. | https://en.wikipedia.org/wiki?curid=17778327 | 2,195,405 |
1,725,791 | Psychophysical studies have suggested that degraded TFS processing due to age and hearing loss may underlie some suprathreshold deficits, such as speech perception; however, debate remains about the underlying neural correlates. The strength of phase locking to the temporal fine structure of signals (TFS) in quiet listening conditions remains normal in peripheral single-neuron responses following cochlear hearing loss. Although these data suggest that the fundamental ability of auditory-nerve fibers to follow the rapid fluctuations of sound remains intact following cochlear hearing loss, deficits in phase locking strength do emerge in background noise. This finding, which is consistent with the common observation that listeners with cochlear hearing loss have more difficulty in noisy conditions, results from reduced cochlear frequency selectivity associated with outer-hair-cell dysfunction. Although only limited effects of age and hearing loss have been observed in terms of TFS coding strength of narrowband sounds, more dramatic deficits have been observed in TFS coding quality in response to broadband sounds, which are more relevant for everyday listening. A dramatic loss of tonotopicity can occur following noise induced hearing loss, where auditory-nerve fibers that should be responding to mid frequencies (e.g., 2–4 kHz) have dominant TFS responses to lower frequencies (e.g., 700 Hz). Notably, the loss of tonotopicity generally occurs only for TFS coding but not for ENV coding, which is consistent with greater perceptual deficits in TFS processing. This tonotopic degradation is likely to have important implications for speech perception, and can account for degraded coding of vowels following noise-induced hearing loss in which most of the cochlea responds to only the first formant, eliminating the normal tonotopic representation of the second and third formants. | https://en.wikipedia.org/wiki?curid=56439577 | 1,724,820 |
216,827 | Landfill sites have been shown to have adverse effects on fetal development. Extensive research has shown that landfills have several negative effects on babies born to mothers living near landfill sites: low birth weight, birth defects, spontaneous abortion, and fetal and infant mortality. Studies done around the Love Canal site near Niagara Falls and the Lipari Landfill in New Jersey have shown a higher proportion of low birth-weight babies than communities farther away from landfills. A study done in California showed a positive correlation between time and quantity of dumping and low birth weights and neonatal deaths. A study in the United Kingdom showed a correlation between pregnant women living near landfill sites and an increased risk of congenital disorders, such as neural tube defects, hypospadias, epispadia, and abdominal wall defects, such as gastroschisis and exomphalos. A study conducted on a Welsh community also showed an increased incidence of gastroschisis. Another study on 21 European hazardous-waste sites showed that those living within 3 km had an increased risk of giving birth to infants with birth defects and that as distance from the land increased, the risk decreased. These birth defects included neural tube defects, malformations of the cardiac septa, anomalies of arteries and veins, and chromosomal anomalies. Looking at communities that live near landfill sites brings up environmental justice. A vast majority of sites are located near poor, mostly black, communities. For example, between the early 1920s and 1978, about 25% of Houston's population was black. However, over 80% of landfills and incinerators during this time were located in these black communities. | https://en.wikipedia.org/wiki?curid=321263 | 216,719 |
1,898,185 | Mechanography (also referred to as "jumping mechanography" or "Muscle Mechanography") is a medical diagnostic measurement method for motion analysis and assessment of muscle function and muscle power by means of physical parameters. The method is based on measuring the variation of the ground reaction forces over the time for motion patterns close to typical every day movements (e.g. chair rise or jumps). From these ground reaction forces centre of gravity related physical parameters like relative maximum forces, velocity, power output, kinetic energy, potential energy, height of jump or whole body stiffness are calculated. If the ground reaction forces are measured separately for left and right leg in addition body imbalances during the motions can be analysed. This enables for example to document the results of therapy. The same methodology can also be used for gait analysis or for analysis of stair climbing, grip strength and Posturography. Due to the utilization of every-day movements reproducibility is high over a wide age range | https://en.wikipedia.org/wiki?curid=13956079 | 1,897,101 |
945,024 | The test surprised the Western powers. American intelligence had estimated that the Soviets would not produce an atomic weapon until 1953, while the British did not expect it until 1954. When the nuclear fission products from the test were detected by the U.S. Air Force, the United States began to follow the trail of the nuclear fallout debris. President Harry S. Truman notified the world of the situation on 23 September 1949: "We have evidence that within recent weeks an atomic explosion occurred in the U.S.S.R." Truman's statement likely in turn surprised the Soviets, who had hoped to keep the test a secret to avoid encouraging the Americans to increase their atomic programs, and did not know that the United States had built a test-detection system using the WB-29 Superfortress. The announcement was a turning point in the Cold War, that had just begun. Once the Soviet Union was confirmed to be in possession of the atomic bomb, pressure mounted to develop the first hydrogen bomb. | https://en.wikipedia.org/wiki?curid=1115854 | 944,522 |
1,433,186 | Iron is also the most abundant transition metal in the human body and it is used in various processes like oxygen transport and ATP production. It plays a key role in the function of enzymes like cytochrome a, b and c as well as iron-sulfur complexes which play an important role in ATP production. It is present in every type of cell in the brain as the brain itself has a very high energy requirement and by extension a very high iron requirement. In animals, iron plays a very important role in transporting oxygen from the lungs to tissues and CO from tissues to the lungs. It does this via two important transport proteins called hemoglobin and myoglobin. Hemoglobin in the blood transports oxygen from the lungs to myoglobin in tissues. Both proteins are tetramer complexes with iron protein complexes called hemes built into each subunit of the tetramer. The oxygen binds to the iron in the heme via affinity-based binding or liganding and dissociates from the protein once it has reached its destination. Iron can also be a potential carcinogen in three ways; first being the production of hydroxyl radicals. Ferric ions can be reduced via superoxide and the product can be reoxidized via peroxide to form hydroxyl radicals. Hydroxyl radicals and other reactive oxygen species when generated near DNA can cause point mutations, cross-linkage and breaks. The second being the bolstering of the growth of neoplastic cells by suppressing host defenses. Excessive iron inhibits the activity of CD lymphocytes and suppresses the tumoricidal activity of macrophages. The third way it can act as a carcinogen is by functioning as an essential nutrient for unrestricted proliferation of tumor cells. | https://en.wikipedia.org/wiki?curid=6327272 | 1,432,382 |
622,204 | Since ancient times, war at sea had been fought much like on land: with melee weapons and bows and arrows, but on floating wooden platforms rather than battlefields. Though the introduction of firearms was a significant change, it only slowly changed the dynamics of ship-to-ship combat. The first guns on ships were small wrought-iron pieces mounted on the open decks and in the fighting tops, often requiring only one or two men to handle them. They were designed to injure, kill or simply stun, shock and frighten the enemy prior to boarding. As guns were made more durable to withstand stronger gunpowder charges, they increased their potential to inflict critical damage to the vessel rather than just its crew. Since these guns were much heavier than the earlier anti-personnel weapons, they had to be placed lower in the ships, and fire from gunports, to avoid ships becoming unstable. In Northern Europe the technique of building ships with clinker planking made it difficult to cut ports in the hull; clinker-built (or clench-built) ships had much of their structural strength in the outer hull. The solution was the gradual adoption of carvel-built ships that relied on an internal skeleton structure to bear the weight of the ship. The development of propulsion during the 15th century from single-masted, square-rigged cogs to three-masted carracks with a mix of square and lateen sails made ships nimbler and easier to maneuver. | https://en.wikipedia.org/wiki?curid=158121 | 621,872 |
402,176 | In his book "Rocks of Ages" (1999), Gould put forward what he described as "a blessedly simple and entirely conventional resolution to ... the supposed conflict between science and religion." He defines the term "magisterium" as "a domain where one form of teaching holds the appropriate tools for meaningful discourse and resolution." The non-overlapping magisteria (NOMA) principle therefore divides the magisterium of science to cover "the empirical realm: what the Universe is made of (fact) and why does it work in this way (theory). The magisterium of religion extends over questions of ultimate meaning and moral value. These two magisteria do not overlap, nor do they encompass all inquiry." He suggests that "NOMA enjoys strong and fully explicit support, even from the primary cultural stereotypes of hard-line traditionalism" and that NOMA is "a sound position of general consensus, established by long struggle among people of goodwill in both magisteria." | https://en.wikipedia.org/wiki?curid=27875 | 401,977 |
1,001,233 | In 2008, Fu and Kane provided a groundbreaking development by theoretically predicting that Majorana bound states can appear at the interface between topological insulators and superconductors. Many proposals of a similar spirit soon followed, where it was shown that Majorana bound states can appear even without any topological insulator. An intense search to provide experimental evidence of Majorana bound states in superconductors first produced some positive results in 2012. A team from the Kavli Institute of Nanoscience at Delft University of Technology in the Netherlands reported an experiment involving indium antimonide nanowires connected to a circuit with a gold contact at one end and a slice of superconductor at the other. When exposed to a moderately strong magnetic field the apparatus showed a peak electrical conductance at zero voltage that is consistent with the formation of a pair of Majorana bound states, one at either end of the region of the nanowire in contact with the superconductor. Simultaneously, a group from Purdue University and University of Notre Dame reported observation of fractional Josephson effect (decrease of the Josephson frequency by a factor of 2) in indium antimonide nanowires connected to two superconducting contacts and subjected to a moderate magnetic field, another signature of Majorana bound states. Bound state with zero energy was soon detected by several other groups in similar hybrid devices, and fractional Josephson effect was observed in topological insulator HgTe with superconducting contacts | https://en.wikipedia.org/wiki?curid=4643400 | 1,000,715 |
49,344 | On July 16, 1957, he made the first supersonic transcontinental flight. Disliking his Bureau of Aeronautics desk job, he devised the flight as both a way to keep flying and publicly demonstrate the F8U Crusader. At that time, the transcontinental speed record, held by an Air Force Republic F-84 Thunderjet, was 3 hours 45 minutes and Glenn calculated that the F8U Crusader could do it faster. Because its air speed was faster than that of a .45 caliber bullet, Glenn called the flight "Project Bullet". He flew an F8U Crusader from Los Alamitos, California to Floyd Bennett Field in New York City in 3 hours, 23 minutes and 8.3 seconds, averaging supersonic speed despite three in-flight refuelings when speeds dropped below . His on-board camera took the first continuous, transcontinental panoramic photograph of the United States. He received his fifth Distinguished Flying Cross for this mission, and was promoted to lieutenant colonel on April 1, 1959. The cross-country flight made Glenn a minor celebrity. A profile appeared in "The New York Times" and he appeared on the television show "Name That Tune". Glenn now had nearly 9,000 hours of flying time, including about 3,000 hours in jets, but knew that at the age of 36, he was now likely too old to continue to fly. | https://en.wikipedia.org/wiki?curid=58702 | 49,324 |
1,302,358 | German engineers have also devoted special attention to the measurement of the flow in rivers; the "Beiträge zur Hydrographie des Königreiches Böhmen" (Prague, 1872–1875) of Andreas Rudolf Harlacher contained valuable measurements of this kind, together with a comparison of the experimental results with the formulae of flow that had been proposed up to the date of its publication, and important data were yielded by the gaugings of the Mississippi made for the United States government by Andrew Atkinson Humphreys and Henry Larcom Abbot, by Robert Gordon's gaugings of the Irrawaddy River, and by Allen J. C. Cunningham's experiments on the Ganges canal. The friction of water, investigated for slow speeds by Coulomb, was measured for higher speeds by William Froude (1810–1879), whose work is of great value in the theory of ship resistance ("Brit. Assoc. Report.", 1869), and stream line motion was studied by Professor Osborne Reynolds and by Professor Henry S. Hele-Shaw. | https://en.wikipedia.org/wiki?curid=2206712 | 1,301,644 |
531,804 | The large number of synthetic organic chemicals currently in production presents a major challenge for timely collection of detailed environmental data on each compound. The concept of structure biodegradability relationships (SBR) has been applied to explain variability in persistence among organic chemicals in the environment. Early attempts generally consisted of examining the degradation of a homologous series of structurally related compounds under identical conditions with a complex "universal" inoculum, typically derived from numerous sources. This approach revealed that the nature and positions of substituents affected the apparent biodegradability of several chemical classes, with resulting general themes, such as halogens generally conferring persistence under aerobic conditions. Subsequently, more quantitative approaches have been developed using principles of QSAR and often accounting for the role of sorption (bioavailability) in chemical fate. | https://en.wikipedia.org/wiki?curid=4387697 | 531,530 |
465,166 | In April 1932, when Curtiss was planning the Model 35B, the United States Navy contracted with the manufacturer for an improved derivative of the Model 34C, F6C as the "F11C". It contained major changes that included the Wright R-1510-98 radial engine, single-leg cantilever main landing-gear units, a slight increase in the interplane gap, metal- rather than fabric-covered control surfaces, and armament based on two fixed forward-firing machine guns supplemented by a hardpoint under the fuselage for the carriage of a bomb, or an auxiliary fuel tank. Curtiss designed the type as the Model 64 Goshawk, with the U.S. Navy designation XF11C-1 (later XBFC-1 after the adoption of the BF for Bomber-Fighter category). The aircraft was of fabric-covered metal construction, used the wing cell structure of the dismantled YP-23, and was delivered in September 1932. | https://en.wikipedia.org/wiki?curid=3054758 | 464,936 |
760,534 | Year after year the older survivors die off in their isolation and unaware of the sort of humanity beyond the small island, until the only people left are Conan and his adoptive grandfather. One day Conan finds on the beach a young girl named Lana, the first stranger and person of his own age whom he had ever known. Lana was raised on another surviving island called High Harbor, where a simple society has re-developed in close contact with the nature. She has ended up on Conan's island while trying to escape from abduction by the crew of the Barracuda, a sailing ship from the leftover of the old world, Industria. Industria is in desperate need of energy, having barely managed to continue its highly industrialized economy through careful husbandry of a backup nuclear reactor, and devolving into a caste-based dystopia. The main resource of highly concentrated orbital-based solar power has become unavailable after the disappearance of Lana's grandfather, Dr. Rao, who has absconded after the war in order to avoid further military usage of his research: a power that could rebuild the world, but was also the weapon bringing humanity on the brink of apocalypse during the last conflict. | https://en.wikipedia.org/wiki?curid=626891 | 760,128 |
1,444,918 | Another popular use of tiling arrays is in finding expressed genes. Traditional methods of gene prediction for annotation of genomic sequences have had problems when used to map the transcriptome, such as not producing an accurate structure of the genes and also missing transcripts entirely. The method of sequencing cDNA to find transcribed genes also runs into problems, such as failing to detect rare or very short RNA molecules, and so do not detect genes that are active only in response to signals or specific to a time frame. Tiling arrays can solve these issues. Due to the high resolution and sensitivity, even small and rare molecules can be detected. The overlapping nature of the probes also allows detection of non-polyadenylated RNA and can produce a more precise picture of gene structure. Earlier studies on chromosome 21 and 22 showed the power of tiling arrays for identifying transcription units. The authors used 25-mer probes that were 35bp apart, spanning the entire chromosomes. Labeled targets were made from polyadenylated RNA. They found many more transcripts than predicted and 90% were outside of annotated exons. Another study with Arabidopsis used high-density oligonucleotide arrays that cover the entire genome. More than 10 times more transcripts were found than predicted by ESTs and other prediction tools. Also found were novel transcripts in the centromeric regions where it was thought that no genes are actively expressed. Many noncoding and natural antisense RNA have been identified using tiling arrays. | https://en.wikipedia.org/wiki?curid=16019737 | 1,444,102 |
157,887 | Deep diving has more hazards and greater risk than basic open water diving. Nitrogen narcosis, the "narks" or "rapture of the deep", starts with feelings of euphoria and over-confidence but then leads to numbness and memory impairment similar to alcohol intoxication. Decompression sickness, or the "bends", can happen if a diver ascends too rapidly, when excess inert gas leaves solution in the blood and tissues and forms bubbles. These bubbles produce mechanical and biochemical effects that lead to the condition. The onset of symptoms depends on the severity of the tissue gas loading and may develop during ascent in severe cases, but is frequently delayed until after reaching the surface. Bone degeneration (dysbaric osteonecrosis) is caused by the bubbles forming inside the bones; most commonly the upper arm and the thighs. Deep diving involves a much greater danger of all of these, and presents the additional risk of oxygen toxicity, which may lead to a convulsion underwater. Very deep diving using a helium-oxygen mixture (heliox) carries a risk of high-pressure nervous syndrome. Coping with the physical and physiological stresses of deep diving requires good physical conditioning. | https://en.wikipedia.org/wiki?curid=291245 | 157,815 |
1,598,228 | where formula_13 is the temperature and formula_14 is the Wigner-Seitz radius (or mean inter-particle spacing), given in terms of the density formula_15 by the expression formula_16. The coupling parameter can be thought of as the ratio of the mean interaction energy between nearest-neighbor pairs, formula_17, and the mean kinetic energy of order formula_18. When this ratio is small, interactions are weak and the plasma is nearly an ideal gas of charges moving in the mean-field produced by the other charges. However, when formula_19 interactions between particles are important and the plasma behaves more like a liquid, or even a crystal if formula_20 is sufficiently large. In fact, computer simulations and theory have predicted that for an infinite homogeneous plasma the system exhibits a gradual onset of short-range order consistent with a liquid-like state for formula_21, and there is predicted to be a first-order phase transition to a body-centered-cubic crystal for formula_22. | https://en.wikipedia.org/wiki?curid=39152193 | 1,597,329 |
1,166,835 | It is a reasonable assumption that until modern treatment was available three-quarters of the SS homozygotes failed to reproduce. To balance this loss of sickle-cell genes, a mutation rate of 1:10.2 per gene per generation would be necessary. This is about 1000 times greater than mutation rates measured in "Drosophila" and other organisms and much higher than recorded for the sickle-cell locus in Africans. To balance the polymorphism, Anthony Allison estimated that the fitness of the AS heterozygote would have to be 1.26 times than that of the normal homozygote. Later analyses of survival figures have given similar results, with some differences from site to site. In Gambians, it was estimated that AS heterozygotes have 90% protection against "P. falciparum"-associated severe anemia and cerebral malaria, whereas in the Luo population of Kenya it was estimated that AS heterozygotes have 60% protection against severe malarial anemia. These differences reflect the intensity of transmission of "P. falciparum" malaria from locality to locality and season to season, so fitness calculations will also vary. In many African populations the AS frequency is about 20%, and a fitness superiority over those with normal hemoglobin of the order of 10% is sufficient to produce a stable polymorphism. | https://en.wikipedia.org/wiki?curid=24973826 | 1,166,217 |
5,902 | Following the 1961 event, FIDE abolished the automatic right of a deposed champion to a rematch, and the next champion, Armenian Tigran Petrosian, a player renowned for his defensive and positional skills, held the title for two cycles, 1963–1969. His successor, Boris Spassky from Russia (champion 1969–1972), won games in both positional and sharp tactical style. The next championship, the so-called Match of the Century, saw the first non-Soviet challenger since World War II, American Bobby Fischer. Fischer defeated his opponents in the Candidates matches by unheard-of margins, and convincingly defeated Spassky for the world championship. The match was followed closely by news media of the day, leading to a surge in popularity for chess; it also held significant political importance at the height of the Cold War, with the match being seen by both sides as a microcosm of the conflict between East and West. In 1975, however, Fischer refused to defend his title against Soviet Anatoly Karpov when he was unable to reach agreement on conditions with FIDE, and Karpov obtained the title by default. Fischer modernized many aspects of chess, especially by extensively preparing openings. | https://en.wikipedia.org/wiki?curid=5134 | 5,899 |
37,008 | Detailed knowledge of fission and fusion weapons is classified to some degree in virtually every industrialized nation. In the United States, such knowledge can by default be classified as "Restricted Data", even if it is created by persons who are not government employees or associated with weapons programs, in a legal doctrine known as "born secret" (though the constitutional standing of the doctrine has been at times called into question; see "United States v. Progressive, Inc."). Born secret is rarely invoked for cases of private speculation. The official policy of the United States Department of Energy has been not to acknowledge the leaking of design information, as such acknowledgment would potentially validate the information as accurate. In a small number of prior cases, the U.S. government has attempted to censor weapons information in the public press, with limited success. According to the "New York Times", physicist Kenneth W. Ford defied government orders to remove classified information from his book, "Building the H Bomb: A Personal History". Ford claims he used only pre-existing information and even submitted a manuscript to the government, which wanted to remove entire sections of the book for concern that foreign nations could use the information. | https://en.wikipedia.org/wiki?curid=2269463 | 36,996 |
1,979,863 | Selecting a cellular site and modifying its characteristics to perform specific functions is one of the most complex studies done in chemistry. Typical modification techniques involved using a catalyst or reaction pairs to change a site of interest. Cysteine residues were used in modifying proteins via bioconjugation because they acted as natural catalysts, however they lacked the ability to target specific sites. Pentelute was inspired to create a new site-selecting approach by altering an amino acid's environment in a peptide sequence. Hence, Pentelute and his lab created an amino acid sequence consisting of phenylalanine, cysteine, proline, and phenylalanine, known as the pi-clamp, to selectively modify a cysteine site in proteins. Having been made from natural compounds, the pi-clamp reacts with a perfluoroaromatic reagent and the cysteine thiol site, thus causing an overall decrease in the reaction's activation energy. Additional advantages of this pi-clamping technique compared to non-natural methods include the clamp being of small size and being able to have direct interaction with the site. This new approach for modification of cells helped researchers target site-specific cells and label proteins without the use of enzymes, which makes the modification process more efficient. A significant use of this method has been applied through the successful killing of breast cancer cells. | https://en.wikipedia.org/wiki?curid=59104462 | 1,978,725 |
1,458,741 | In 2016 there has been renewed discussion about Finland's energy policy. Finland imports over 20% of the electricity used at peak usage. For example, in the hour between 17-18 on January 7, 2016, during a period of extreme cold, Finland imported 4,300 MW (28.5%) out of a record 15,100 MW of total usage (average over 1 hour). The delays in the construction of the third reactor at the Olkiluoto Nuclear Power Plant (est. 1,600 MWe when completed), which was projected to be operating commercially by 2010 but is now being estimated to be completed no earlier than 2022, have caused a significant domestic energy production deficit. A consortium of Finnish industry and power companies called Fennovoima has applied and been granted a permission to build another new nuclear power plant, delivered by Russia's Rosatom, which also has a 1/3 stake on the power plant. This has caused some concern among observers about Russia being able to manipulate Nordic electricity prices or use the power plant as a leverage in conflict situations. The plant was estimated to be operational by 2024 and projected to produce 1,200 MW of electricity, but all work was stopped in 2022 due to the Russian invasion of Ukraine. | https://en.wikipedia.org/wiki?curid=27119495 | 1,457,921 |
626,082 | In vitro studies on human and animal cells and tissues and in vivo animal model studies indicate that certain EDPs and EEQs (16,17-EDPs, 19,20-EDPs, 17,18-EEQs have been most often examined) have actions which often oppose those of another product of CYP450 enzymes (e.g. CYP4A1, CYP4A11, CYP4F2, CYP4F3A, and CYP4F3B) viz., 20-Hydroxyeicosatetraenoic acid (20-HETE), principally in the areas of blood pressure regulation, blood vessel thrombosis, and cancer growth (see 20-Hydroxyeicosatetraenoic acid, epoxyeicosatetraenoic acid, and epoxydocosapentaenoic acid sections on activities and clinical significance). Such studies also indicate that the eicosapentaenoic acids and EEQs are: 1) more potent than EETs in decreasing hypertension and pain perception; 2) more potent than or equal in potency to the EETs in suppressing inflammation; and 3) act oppositely from the EETs in that they inhibit angiogenesis, endothelial cell migration, endothelial cell proliferation, and the growth and metastasis of human breast and prostate cancer cell lines whereas EETs have stimulatory effects in each of these systems. Consumption of omega-3 fatty acid-rich diets dramatically raises the serum and tissue levels of EDPs and EEQs in animals as well as humans, and in humans is by far the most prominent change in the profile of polyunsaturated fatty acids metabolites caused by dietary omega-3 fatty acids. | https://en.wikipedia.org/wiki?curid=4779665 | 625,749 |
455,635 | The first classical explanation was provided in 1729, by James Bradley as described above, who attributed it to the finite speed of light and the motion of Earth in its orbit around the Sun. However, this explanation proved inaccurate once the wave nature of light was better understood, and correcting it became a major goal of the 19th century theories of luminiferous aether. Augustin-Jean Fresnel proposed a correction due to the motion of a medium (the aether) through which light propagated, known as "partial aether drag". He proposed that objects partially drag the aether along with them as they move, and this became the accepted explanation for aberration for some time. George Stokes proposed a similar theory, explaining that aberration occurs due to the flow of aether induced by the motion of the Earth. Accumulated evidence against these explanations, combined with new understanding of the electromagnetic nature of light, led Hendrik Lorentz to develop an electron theory which featured an immobile aether, and he explained that objects contract in length as they move through the aether. Motivated by these previous theories, Albert Einstein then developed the theory of special relativity in 1905, which provides the modern account of aberration. | https://en.wikipedia.org/wiki?curid=2703 | 455,413 |
932,966 | The dopaminergic pathways that project from the substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) into the striatum (i.e., the nigrostriatal and mesolimbic pathways, respectively) form one component of a sequence of pathways known as the cortico-basal ganglia-thalamo-cortical loop. The nigrostriatal component of the loop consists of the SNc, giving rise to both inhibitory and excitatory pathways that run from the striatum into the globus pallidus, before carrying on to the thalamus, or into the subthalamic nucleus before heading into the thalamus. The dopaminergic neurons in this circuit increase the magnitude of phasic firing in response to positive reward error, that is when the reward exceeds the expected reward. These neurons do not decrease phasic firing during a negative reward prediction (less reward than expected), leading to hypothesis that serotonergic, rather than dopaminergic neurons encode reward loss (source?). Dopamine phasic activity also increases during cues that signal negative events, however dopaminergic neuron stimulation still induces place preference, indicating its main role in evaluating a positive stimulus. From these findings, two hypotheses have developed, as to the role of the basal ganglia and nigrostiatal dopamine circuits in action selection. The first model suggests a "critic" which encodes value, and an actor which encodes responses to stimuli based on perceived value. However, the second model proposes that the actions do not originate in the basal ganglia, and instead originate in the cortex and are selected by the basal ganglia. This model proposes that the direct pathway controls appropriate behavior and the indirect suppresses actions not suitable for the situation. This model proposes that tonic dopaminergic firing increases the activity of the direct pathway, causing a bias towards executing actions faster. | https://en.wikipedia.org/wiki?curid=673153 | 932,474 |
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