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119,579 | This data could be used to produce maps of the state of the atmosphere for a region near the Earth's surface and to study how these states evolved through time. To make frequent weather forecasts based on these data required a reliable network of observations, but it was not until 1849 that the Smithsonian Institution began to establish an observation network across the United States under the leadership of Joseph Henry. Similar observation networks were established in Europe at this time. The Reverend William Clement Ley was key in understanding of cirrus clouds and early understandings of Jet Streams. Charles Kenneth Mackinnon Douglas, known as 'CKM' Douglas read Ley's papers after his death and carried on the early study of weather systems. | https://en.wikipedia.org/wiki?curid=19904 | 119,530 |
1,900,862 | During the late 1970s, rising fuel costs and the demand for a cleaner environment gave impetus to advance technology which used solar energy to create electricity. Studies identified the central receiver concept as having high potential to generate electricity on a large scale. The United States government initiated support through the National Science Foundation Research Applied to National Needs (RANN) program in 1972 which was eventually funded by the Energy Research and Development Administration and the Department of Energy. Six central receiver pilot plants were constructed including the 5 MW (thermal) test facility at Sandia National Laboratories. | https://en.wikipedia.org/wiki?curid=37210492 | 1,899,773 |
518,727 | The fundamental design decisions in building a reactor are the choice of fuel, coolant and neutron moderator. The choice of fuel was straightforward; only natural uranium was available. The decision that the reactor would use graphite as a neutron moderator caused little debate. Although with heavy water as moderator the number of neutrons produced for every one absorbed (known as "k") was 10 percent more than in the purest graphite, heavy water would be unavailable in sufficient quantities for at least a year. This left the choice of coolant, over which there was much discussion. A limiting factor was that the fuel slugs would be clad in aluminum, so the operating temperature of the reactor could not exceed . The theoretical physicists in Wigner's group at the Metallurgical Laboratory developed several designs. In November 1942, the DuPont engineers chose helium gas as the coolant for the production plant, mainly on the basis that it did not absorb neutrons, but also because it was inert, which removed the issue of corrosion. | https://en.wikipedia.org/wiki?curid=4110093 | 518,458 |
1,485,695 | Protein mutation tolerance is the product of two main features: the structure of the genetic code and protein structural robustness. Proteins are resistant to mutations because many sequences can fold into highly similar structural folds. A protein adopts a limited ensemble of native conformations because those conformers have lower energy than unfolded and mis-folded states (ΔΔG of folding). This is achieved by a distributed, internal network of cooperative interactions (hydrophobic, polar and covalent). Protein structural robustness results from few single mutations being sufficiently disruptive to compromise function. Proteins have also evolved to avoid aggregation as partially folded proteins can combine to form large, repeating, insoluble protein fibrils and masses. There is evidence that proteins show negative design features to reduce the exposure of aggregation-prone beta-sheet motifs in their structures. | https://en.wikipedia.org/wiki?curid=31066305 | 1,484,857 |
376,527 | Manipulation of the electron beam is performed using two physical effects. The interaction of electrons with a magnetic field will cause electrons to move according to the left hand rule, thus allowing for electromagnets to manipulate the electron beam. The use of magnetic fields allows for the formation of a magnetic lens of variable focusing power, the lens shape originating due to the distribution of magnetic flux. Additionally, electrostatic fields can cause the electrons to be deflected through a constant angle. Coupling of two deflections in opposing directions with a small intermediate gap allows for the formation of a shift in the beam path, allowing for beam shifting in TEM, which is important for STEM. From these two effects, as well as the use of an electron imaging system, sufficient control over the beam path is possible for TEM operation. The optical configuration of a TEM can be rapidly changed, unlike that for an optical microscope, as lenses in the beam path can be enabled, have their strength changed, or be disabled entirely simply via rapid electrical switching, the speed of which is limited by effects such as the magnetic hysteresis of the lenses. | https://en.wikipedia.org/wiki?curid=214513 | 376,332 |
259,260 | Working memory is impaired by acute and chronic psychological stress. This phenomenon was first discovered in animal studies by Arnsten and colleagues, who have shown that stress-induced catecholamine release in PFC rapidly decreases PFC neuronal firing and impairs working memory performance through feedforward, intracellular signaling pathways. Exposure to chronic stress leads to more profound working memory deficits and additional architectural changes in PFC, including dendritic atrophy and spine loss, which can be prevented by inhibition of protein kinase C signaling. fMRI research has extended this research to humans, and confirms that reduced working memory caused by acute stress links to reduced activation of the PFC, and stress increased levels of catecholamines. Imaging studies of medical students undergoing stressful exams have also shown weakened PFC functional connectivity, consistent with the animal studies. The marked effects of stress on PFC structure and function may help to explain how stress can cause or exacerbate mental illness. | https://en.wikipedia.org/wiki?curid=33912 | 259,126 |
1,229,848 | The word "algorism" comes from the name Al-Khwārizmī (c. 780–850), a Persian mathematician, astronomer, geographer and scholar in the House of Wisdom in Baghdad, whose name means "the native of Khwarezm", which is now in modern-day Uzbekistan. He wrote a treatise in Arabic language in the 9th century, which was translated into Latin in the 12th century under the title "Algoritmi de numero Indorum". This title means "Algoritmi on the numbers of the Indians", where "Algoritmi" was the translator's Latinization of Al-Khwarizmi's name. Al-Khwarizmi was the most widely read mathematician in Europe in the late Middle Ages, primarily through his other book, the Algebra. In late medieval Latin, "algorismus", the corruption of his name, simply meant the "decimal number system" that is still the meaning of modern English algorism. During the 17th century, the French form for the word – but not its meaning – was changed to "algorithm", following the model of the word "logarithm", this form alluding to the ancient Greek . English adopted the French very soon afterwards, but it wasn't until the late 19th century that "algorithm" took on the meaning that it has in modern English. In English, it was first used about 1230 and then by Chaucer in 1391. Another early use of the word is from 1240, in a manual titled "Carmen de Algorismo" composed by Alexandre de Villedieu. It begins thus: | https://en.wikipedia.org/wiki?curid=417534 | 1,229,186 |
1,379,526 | Presently, a range of techniques have been developed to prepare GQDs. These methods are normally classified into two groups top down and bottom up. Top down approaches applied different techniques to cut bulk graphitic materials into GQDs including graphite, graphene, carbon nanotubes, coal, carbon black and carbon fibres. These techniques mainly include electron beam lithography, chemical synthesis, electrochemical preparation, graphene oxide (GO) reduction, C60 catalytic transformation, the microwave assisted hydrothermal method (MAH), the Soft-Template method, the hydrothermal method, and the ultrasonic exfoliation method. Top down methods usually need intense purification as strong mixed acids are used in these methods. On the other hand, bottom up methods assemble GQDs from small organic molecules such as citric acid and glucose. These GQDs have better biocompatibility. | https://en.wikipedia.org/wiki?curid=45426554 | 1,378,764 |
1,011,231 | In the last thirty years of the 20th century, equipment which would generally have used electromechanical devices became less expensive. This equipment became cheaper because it used more reliably integrated microcontroller circuits containing ultimately a few million transistors, and a program to carry out the same task through logic. With electromechanical components there were only moving parts, such as mechanical electric actuators. This more reliable logic has replaced most electromechanical devices, because any point in a system which must rely on mechanical movement for proper operation will inevitably have mechanical wear and eventually fail. Properly designed electronic circuits without moving parts will continue to operate correctly almost indefinitely and are used in most simple feedback control systems. Circuits without moving parts appear in a large number of items from traffic lights to washing machines. | https://en.wikipedia.org/wiki?curid=31322120 | 1,010,710 |
1,781,931 | The BAA continues to contribute to the science of astronomy, even despite modern competition from space-based telescopes and highly automated professional observatories. Modern digital sensors, coupled with techniques such as lucky imaging, mean that even modest amateur equipment can rival what professional observatories could have achieved a few decades ago. The vastness of the night sky, together with the sheer number of amateur observatories, mean that BAA members are often the first to pick up new phenomena. In recent years, the Association's leading supernova hunter, Tom Boles (President 2003–5), has discovered over 150 supernovae. He now holds the world record for the greatest number of such events discovered by any individual in history. | https://en.wikipedia.org/wiki?curid=1189630 | 1,780,927 |
754,985 | The Allied Operation Diadem of the Italian Campaign in May 1944 successfully assaulted German Gustav Line defences in the Italian Liri valley, the primary route to Rome. Breaking through German lines, it eased pressure on the Anzio beachhead and tied German troops up in Italy to prevent their deployment against the Normandy landings. Diadem was supported by air attacks called Operation Strangle and by the British XIII Corps, and the French Corps, including Moroccan Goumiers). The opposing force was the German 10th Army. On 11 May 1944, elements of the British 4th Infantry Division and 8th Indian Infantry Division, with supporting fire from the 1st Canadian Armoured Brigade, performed a successful night crossing of the Garigliano and Rapido rivers, against strong resistance. The French Corps pushed through the mountains on 14 May, supported by US II Corps of the Fifth Army. On 17 May, Polish II Corps on the right attacked Monte Cassino. | https://en.wikipedia.org/wiki?curid=376965 | 754,582 |
1,766,017 | Drug-interaction studies and post hoc analyses of Phase III studies showed no clinically relevant interaction of sucroferric oxyhydroxide with the systemic exposures to losartan, furosemide, omeprazole, digoxin, and warfarin, the lipid-lowering effects of statins, and oral vitamin D receptor agonists. According to the European label (Summary of Product Characteristics), medicinal products that are known to interact with iron (e.g. doxycycline) or have the potential to interact with Velphoro should be administered at least one hour before or two hours after Velphoro. This allows sucroferric oxyhydroxide to bind phosphate as intended and be excreted without coming into contact with medications in the gut that it might interact with. According to the US prescribing information, Velphoro should not be prescribed with oral levothyroxine. The combination of sucroferric oxyhydroxide and levothyroxine is contraindicated because sucroferric oxyhydroxide contains iron, which may cause levothyroxine to become insoluble in the gut, thereby preventing the intestinal absorption of levothyroxine. | https://en.wikipedia.org/wiki?curid=43796848 | 1,765,023 |
80,056 | Pinnipeds have an amphibious lifestyle; they spend most of their lives in the water, but haul out to mate, raise young, molt, rest, thermoregulate or escape from aquatic predators. Several species are known to migrate vast distances, particularly in response to extreme environmental changes, like El Niño or changes in ice cover. Elephant seals stay at sea 8–10 months a year and migrate between breeding and molting sites. The northern elephant seal has one of the longest recorded migration distances for a mammal, at . Phocids tend to migrate more than otariids. Traveling seals may use various features of their environment to reach their destination including geomagnetic fields, water and wind currents, the position of the sun and moon and the taste and temperature of the water. | https://en.wikipedia.org/wiki?curid=60261 | 80,023 |
1,026,108 | Asimov was a claustrophile: "I wrote a novel in 1953 which pictured a world in which everyone lived in underground cities, comfortably enclosed away from the open air. People would say, 'How could you imagine such a nightmarish situation?' And I would answer in astonishment, 'What nightmarish situation? The "caves of steel" are vast city complexes covered by huge metallic domes, capable of supporting tens of millions each: the New York City of that era (wherein much of the story is set) encompasses present-day New York City as well as large tracts of New Jersey. Asimov imagines the present day underground transit connected to malls and apartment blocks, until no one ever exits the domes and most of the population suffer from extreme fear of leaving them. (Even though the "Robot" and "Foundation" series were not made part of the same fictional universe until much later, the "caves of steel" resemble the planet Trantor.) | https://en.wikipedia.org/wiki?curid=60129 | 1,025,574 |
400,624 | Plato first articulated the emission theory, the idea that visual perception is accomplished by rays emitted by the eyes. He also commented on the parity reversal of mirrors in "Timaeus". Some hundred years later, Euclid (4th–3rd century BC) wrote a treatise entitled "Optics" where he linked vision to geometry, creating "geometrical optics". He based his work on Plato's emission theory wherein he described the mathematical rules of perspective and described the effects of refraction qualitatively, although he questioned that a beam of light from the eye could instantaneously light up the stars every time someone blinked. Euclid stated the principle of shortest trajectory of light, and considered multiple reflections on flat and spherical mirrors. | https://en.wikipedia.org/wiki?curid=22483 | 400,425 |
1,941,910 | It comprises 36 principal investigators, has a budget of C$90 million (2005/6), has over 200 trainees and approximately 600 staff. The institute conducts research into various forms of cancer (colon, breast, pancreatic, prostate, lung, etc.), neurological disorders and brain illnesses, women's and infants' health, diabetes, developmental biology, stem cell biology and tissue regeneration, mouse models of human disease, genomic medicine and systems biology. The institute has of space and is split between the main hospital and the Joseph and Wolf Lebovic Health Complex. | https://en.wikipedia.org/wiki?curid=5684310 | 1,940,799 |
1,820,678 | Purinergic receptors have been found in the cells of the Organ of Corti, which are able to mediate physiological and pathophysiological actions. There are various types of purinergic receptors, the most common expressed in the Hensen's cells is the P2 subtype. Another metabotropic P2Y receptor subtypes are also expressed in the cochlea, P2Y1, P2Y2, P2Y4, and P2Y6 are found in the Hensen's cells. The P2X is ionotropic and P2Y is metabotropic, which have different functions at different sites in the organ of Corti, for example, P2X2 receptor subunits are able to mediate ATP-induced reduction in endo cochlear potential, which are responsible for the protection of the cochlear when responding to loud noise. After the noise exposure, the ATP levels elevated and change the K+ conductance through the P2X receptors by reducing the endo cochlear potential (EP). As a result, the purinergic signaling mechanism act as a regulation of homeostasis which decrease the cochlear sensitivity to noise exposure, loss function of the purinergic receptors expressed in the Hensen's cells in the cochlea may lead to noise-induced hearing loss (NIHL). NIHL could also happen if there is elevated Ca2+ concentration in the cochlea. The ionized calcium plays a critical role in many functions, such as cell proliferation, differentiation, and cell apoptosis, there are several factors that cause the increased concentration in the cochlea, including continuous exposure to noise which lead to overstimulation, thus maintaining homeostasis of the Ca2+ concentration is important. | https://en.wikipedia.org/wiki?curid=60786107 | 1,819,641 |
2,233,230 | Pectocarya heterocarpa is a species of flowering plant in the borage family known by the common names chuckwalla combseed and mixed-nut pectocarya. It is native to the southwestern United States and northern Mexico, where it grows in desert, mountain and plateau habitat, in scrub, woodland, and open areas. This is an annual herb producing a slender, rough-haired stem prostrate or upright to a maximum length of about 25 centimeters. The small, pointed linear leaves are alternately arranged, widely spaced along the stem. The inflorescence is a series of flowers, each on a curved pedicel. The flower has small green sepals and tiny white petals. The fruit is an array of four nutlets each lined with comblike prickles. | https://en.wikipedia.org/wiki?curid=25417133 | 2,231,962 |
101,488 | Magnetostrictive transducers were pursued after World War II as an alternative to piezoelectric ones. Nickel scroll-wound ring transducers were used for high-power low-frequency operations, with size up to in diameter, probably the largest individual sonar transducers ever. The advantage of metals is their high tensile strength and low input electrical impedance, but they have electrical losses and lower coupling coefficient than PZT, whose tensile strength can be increased by prestressing. Other materials were also tried; nonmetallic ferrites were promising for their low electrical conductivity resulting in low eddy current losses, Metglas offered high coupling coefficient, but they were inferior to PZT overall. In the 1970s, compounds of rare earths and iron were discovered with superior magnetomechanic properties, namely the Terfenol-D alloy. This made possible new designs, e.g. a hybrid magnetostrictive-piezoelectric transducer. The most recent of these improved magnetostrictive materials is Galfenol. | https://en.wikipedia.org/wiki?curid=29438 | 101,443 |
496,156 | only when formula_10. Here, formula_11 and formula_12 are the dimensions of the plate, and formula_13 is the difference in forces. The Wilhelmy plate measurements give pressure – area isotherms that show phase transition-like behaviour of the LM films, as mentioned before (see figure below). In the gaseous phase, there is minimal pressure increase for a decrease in area. This continues until the first transition occurs and there is a proportional increase in pressure with decreasing area. Moving into the solid region is accompanied by another sharp transition to a more severe area dependent pressure. This trend continues up to a point where the molecules are relatively close packed and have very little room to move. Applying an increasing pressure at this point causes the monolayer to become unstable and destroy the monolayer forming polylayer structures towards the air phase. The surface pressure during the monolayer collapse may remain approximately constant (in a process near the equilibrium) or may decay abruptly (out of equilibrium - when the surface pressure was over-increased because lateral compression was too fast for monomolecular rearrangements). | https://en.wikipedia.org/wiki?curid=2227503 | 495,900 |
304,540 | The expansion of worldwide activities in gravitational-wave detection to produce an effective global network has been a goal of LIGO for many years. In 2010, a developmental roadmap issued by the Gravitational Wave International Committee (GWIC) recommended that an expansion of the global array of interferometric detectors be pursued as a highest priority. Such a network would afford astrophysicists with more robust search capabilities and higher scientific yields. The current agreement between the LIGO Scientific Collaboration and the Virgo collaboration links three detectors of comparable sensitivity and forms the core of this international network. Studies indicate that the localization of sources by a network that includes a detector in India would provide significant improvements. Improvements in localization averages are predicted to be approximately an order of magnitude, with substantially larger improvements in certain regions of the sky. | https://en.wikipedia.org/wiki?curid=81610 | 304,378 |
294,496 | The intake system was simplified in shape to reduce induction resistance and noise. A larger twin-chambered air box designed to dampen resonant intake tract noise replaces the previous Accord's smaller, single-chamber damper. The new box is 10.7 liters in capacity, compared to the older unit's 8.2 liters. The larger box also eliminates the need for a second resonant-frequency damper and an additional side branch. The 2.3-liter Accord 4-cylinder engine intake manifold has been redesigned to add more power and lower emissions. The individual cast-aluminum runners have revised dimensions to better take advantage of the different air-flow characteristics of the 2.3-liter engine. A larger plenum chamber reduces induction noise and the incorporation of exhaust gas recirculation (EGR) ports into the plenum, upstream of the throttle plates, eliminates the need for a separate fitting and port in each intake runner. | https://en.wikipedia.org/wiki?curid=2224384 | 294,336 |
1,454,933 | The western yellowjacket foraging behavior is similar to other "Vespula" species. Yellowjackets forage for insects and dead animals for meat and plant nectar for carbohydrates. The captured prey is typically taken to a more vertical surface and malaxated by chewing off legs and wings. In larger insects, the head is typically removed first. Foraging for prey requires visual cues, but odors can be used when scavenging for protein. Hunting for prey and dead animals occurs individually because yellowjacket workers are unable to communicate the location of food to other workers in the colony. All workers forage for honey, water, and fiber. In Hawaii, yellowjackets rob honey bee colonies through two major types of raids. Sometimes, yellowjackets enter and leave in a slow but steady traffic faced by opposition from honey bee workers. In the more common raid, yellowjackets enter individually and experience no apparent opposition. "V. pensylvanica" utilize their mandibles to scrape weathered wood and dried herbaceous stems to obtain resources rich in fiber. | https://en.wikipedia.org/wiki?curid=21851203 | 1,454,113 |
366,399 | No. 616 Squadron exchanged its F.1s for the first "Meteor F.3"s on 18 December 1944. These first 15 F.3s differed from the F.1 in having a sliding canopy in place of the sideways hinging canopy, increased fuel capacity and some airframe refinements. They were still powered by Welland I engines. Later F.3s were equipped with the Derwent I engines. This was a substantial improvement over the earlier mark, although the basic design still had not reached its potential. Wind tunnel and flight tests demonstrated that the original short nacelles, which did not extend far fore and aft of the wing, contributed heavily to compressibility buffeting at high speed. New, longer nacelles not only cured some of the compressibility problems but added at altitude, even without upgraded powerplants. The last batch of Meteor F.3s featured the longer nacelles; other F.3s were retrofitted in the field with the new nacelles. The F.3 also had the new Rolls-Royce Derwent engines, increased fuel capacity, and a new larger, more strongly raked bubble canopy. | https://en.wikipedia.org/wiki?curid=42702 | 366,207 |
1,567,075 | In 1930 Walther Bothe and Herbert Becker in Germany found that alpha particles striking light elements such as beryllium, boron, or lithium would release a highly penetrating radiation, at first believed to be gamma radiation, although it was more penetrating than any gamma rays known. The next important contribution was reported in 1932 by Irène Joliot-Curie and Frédéric Joliot in Paris, who showed that if this unknown radiation fell on paraffin wax or any other hydrogen-containing compound it ejected protons of very high energy. Finally, in 1932 the physicist James Chadwick in England performed a series of experiments showing that the gamma ray hypothesis was untenable, and suggested that the new radiation consisted of uncharged particles of approximately the mass of the proton. He performed a series of experiments to verify this, these uncharged particles were eventually called "neutrons", and Chadwick is credited with this discovery. | https://en.wikipedia.org/wiki?curid=15581606 | 1,566,188 |
1,908,791 | Evans has been featured in numerous documentaries, including the History Channel's 2015 documentary "Dino Hunt Canada" and various episodes of Daily Planet and radio and TV interviews, as well as appeared in the TVOKids series Now You Know & "Dino Dan: Trek's Adventures". He has also helped to develop several exhibits, including the traveling "Ultimate Dinosaurs" exhibit in 2012, the permanent James and Louise Temerty Galleries of the Age of Dinosaurs at the Royal Ontario Museum (ROM), and temporary exhibits at the ROM, including "Dinosaur Eggs & Babies: Remarkable Fossils from South Africa" (2014) and "Zuul, Life of an Armoured Dinosaur" (2018-2019). Evans has also served on numerous committees of the Society of Vertebrate Paleontology and the Canadian Society of Vertebrate Paleontology. | https://en.wikipedia.org/wiki?curid=62883473 | 1,907,693 |
332,632 | Integrated production sites are characterized by co-location of many individual production lines (producing a specific chemical), which share an interconnected material flow. Piping is used ubiquitously for volume materials. All production lines use common raw material sourcing and feed back waste resources, which can be used elsewhere (e.g. steam of various temperatures, sulfuric acid, carbon monoxide). The economic incentive for this approach is high resource and energy efficiency of the overall process, reduced shipping cost and associated reduced risk of accidents. Due to the high cost of such an integrated production site, it establishes a high entry barrier for competitors trying to enter the market for volume chemicals. | https://en.wikipedia.org/wiki?curid=171595 | 332,455 |
1,634,607 | Although acoustic Doppler velocimetry (ADV) has become a popular technique in laboratory in field applications, several researchers pointed out accurately that the ADV signal outputs include the combined effects of turbulent velocity fluctuations, Doppler noise, signal aliasing, turbulent shear and other disturbances. Evidences included by high levels of noise and spikes in all velocity components. In turbulent flows, the ADV velocity outputs are a combination of Doppler noise, signal aliasing, velocity fluctuations, installation vibrations and other disturbances. The signal may be further affected adversely by velocity shear across the sampling volume and boundary proximity. Lemmin and Lhermitte, Chanson et al., and Blanckaert and Lemmin discussed the inherent Doppler noise of an ADV system. Spikes may be caused by aliasing of the Doppler signal. McLelland and Nicholas explained the physical processes while Nikora and Goring, Goring and Nikora and Wahl developed techniques to eliminate aliasing errors called "spikes". These methods were developed for steady flow situations and tested in man-made channels. Not all of them are reliable, and the phase-space thresholding despiking technique appears to be a robust method in steady flows ). Simply, "raw" ADV velocity data are not "true" turbulent velocities and they should never be used without adequate post-processing (e.g.,). Chanson presented a summary of experiences gained during laboratory and field investigations with both Sontek and Nortek ADV systems. | https://en.wikipedia.org/wiki?curid=22366672 | 1,633,684 |
1,615,887 | The college was the first agricultural research facility in Greece. As its Greek name shows (Ανωτάτη Γεωπονική Σχολή Αθηνών) the college was originally modeled after the French Grandes Ecoles. First rector was Spyridon Hasiotis who is considered the father of agricultural science in Greece. In the early years the college lacked financial resources and teaching facilities. To help overcome this problem a special fund was set up in 1928. The main income of the university was from the sale of its produce, while the buildings of the Triantafillideios School of Agriculture were inadequate for the needs of a college. At that time the university was under the auspices of the Ministry of Agriculture which guaranteed employment to all of its graduates, thus making the university very attractive to people of poor background. Students and faculty were involved in politics, something that the Metaxas dictatorship did not like and thus moved the college to Thessaloniki in 1937, to become part of the Aristotle University of Thessaloniki. | https://en.wikipedia.org/wiki?curid=4111049 | 1,614,978 |
1,615,745 | Synchrotron Radiation Computed Tomography uses a monochromatic and parallel X-ray beam to measure the value of cerebral blood volume. It allows the sample to be placed away from the detector, thereby avoiding scattering effects. This technique measures absolute contrast concentration with relatively high precision and spatial resolution. Cerebral blood volume measurements are based on methods used in dynamic computed tomography. After a large dose of iodinated contrast agent was injected into the brain tissue, the temporal change in iodine concentration was compared to changes in cerebral arterial input. It is a new method for studying hemodynamic changes in brain pathophysiology, including clinical studies of cerebrovascular diseases or brain tumors. | https://en.wikipedia.org/wiki?curid=59024501 | 1,614,836 |
2,061,724 | Recent progress on the phenomenon of many-body localization has revealed classes of generic (typically disordered) many-body systems which "never" reach local thermal equilibrium, and thus lie outside the framework of equilibrium statistical mechanics. MBL systems can undergo a dynamical phase transition to a thermalizing phase as parameters such as the disorder or interaction strength are tuned, and the nature of the MBL-to-thermal phase transition is an active area of research. The existence of MBL raises the interesting question of whether one can have different kinds of MBL phases, just as there are different kinds of thermalizing phases. Remarkably, the answer is affirmative, and out-of-equilibrium systems can also display a rich phase structure. What's more, the suppression of thermal fluctuations in localized systems can even allow for new kinds of order that are forbidden in equilibrium -- which is the essence of localization-protected quantum order. The recent discovery of time-crystals in periodically driven MBL systems is a notable example of this phenomenon. | https://en.wikipedia.org/wiki?curid=59188974 | 2,060,536 |
1,821,014 | While the original design was being worked on, the team had to constantly tune the software for maximum performance. This led to continual ROM updates, causing considerable problems. This led to increasing interest in a RAM-based machine that booted from the network, reversing their earlier decision. In 1989 development along these lines started using the VAXstation 3100 with the hard drive and other components removed, running the VAXELN operating system and EWS (X11 for VAXELN). As the system could only be used with a host computer, there was no local user interface. Implementing this version of the system required considerably more hardware and expense, so the decision was made to make this a color-only model, in comparison to the earlier models which were monochrome. | https://en.wikipedia.org/wiki?curid=47910793 | 1,819,977 |
300,209 | Between 1886 and 1889 Hertz conducted a series of experiments that would prove the effects he was observing were results of Maxwell's predicted electromagnetic waves. Starting in November 1887 with his paper "On Electromagnetic Effects Produced by Electrical Disturbances in Insulators", Hertz sent a series of papers to Helmholtz at the Berlin Academy, including papers in 1888 that showed transverse free space electromagnetic waves traveling at a finite speed over a distance. In the apparatus Hertz used, the electric and magnetic fields radiated away from the wires as transverse waves. Hertz had positioned the oscillator about 12 meters from a zinc reflecting plate to produce standing waves. Each wave was about 4 meters long. Using the ring detector, he recorded how the wave's magnitude and component direction varied. Hertz measured Maxwell's waves and demonstrated that the velocity of these waves was equal to the velocity of light. The electric field intensity, polarization and reflection of the waves were also measured by Hertz. These experiments established that light and these waves were both a form of electromagnetic radiation obeying the Maxwell equations.. | https://en.wikipedia.org/wiki?curid=13445 | 300,048 |
1,955,441 | Spanish and German doctors, in 1905 and 1915 respectively, used intraoperative radiation therapy (IORT) in an attempt to eradicate residual tumors left behind after surgical resection. However, radiation equipment in the early twentieth-century could only deliver low energy X-rays, which had relatively poor penetration; high doses of radiation could not be applied externally without doing unacceptable damage to normal tissues. IORT treatments with low energy or "orthovoltage" X-rays gained advocates throughout the 1930s and 1940s, but the results were inconsistent. The X-rays penetrated beyond the tumor bed to the normal tissues beneath, had poor dose distributions, and took a relatively long time to administer. The technique was largely abandoned in the late 1950s with the advent of megavoltage radiation equipment, which enabled the delivery of more penetrating external radiation. | https://en.wikipedia.org/wiki?curid=13524515 | 1,954,319 |
1,364,073 | Certain physical paradoxes defy common sense predictions about physical situations. In some cases, this is the result of modern physics correctly describing the natural world in circumstances which are far outside of everyday experience. For example, special relativity has traditionally yielded two common paradoxes: the twin paradox and the ladder paradox. Both of these paradoxes involve thought experiments which defy traditional common sense assumptions about time and space. In particular, the effects of time dilation and length contraction are used in both of these paradoxes to create situations which seemingly contradict each other. It turns out that the fundamental postulate of special relativity that the speed of light is invariant in all frames of reference requires that concepts such as simultaneity and absolute time are not applicable when comparing radically different frames of reference. | https://en.wikipedia.org/wiki?curid=1716550 | 1,363,317 |
116,625 | There have been at least 80 commercial recordings of "The Planets". Holst conducted the London Symphony Orchestra in the first two recorded performances: the first was an acoustic recording made in sessions between September 1922 and November 1923; the second was made in 1926 using the new electrical recording process. Holst's tempi are in general faster than those of most of his successors on record. This may have been due to the need to fit the music on 78 rpm discs, although later 78 versions are slower. Holst's later recording is quicker than the acoustic version, possibly because the electrical process required wider grooves, reducing the available playing time. Other, slower, recordings from the 78 era include those conducted by Leopold Stokowski (1943) and Sir Adrian Boult (1945). Recordings from the LP age are also typically longer than the composer's, but from the digital era a 2010 recording by the London Philharmonic Orchestra conducted by Vladimir Jurowski is quicker than Holst's acoustic version and comes close to matching his 1926 speeds, and in two movements (Venus and Uranus) surpasses them. There were no commercial recordings of the work in the 1930s; timings are given below of a recording representing each subsequent decade up to the 2010s: | https://en.wikipedia.org/wiki?curid=49243 | 116,580 |
1,885,802 | A loline alkaloid is a member of the 1-aminopyrrolizidines (often referred to as lolines), which are bioactive natural products with several distinct biological and chemical features. The lolines are insecticidal and insect-deterrent compounds that are produced in grasses infected by endophytic fungal symbionts of the genus "Epichloë" (anamorph species: "Neotyphodium"). Lolines increase resistance of endophyte-infected grasses to insect herbivores, and may also protect the infected plants from environmental stresses such as drought and spatial competition. They are alkaloids, organic compounds containing basic nitrogen atoms. The basic chemical structure of the lolines comprises a saturated pyrrolizidine ring, a primary amine at the C-1 carbon, and an internal ether bridge—a hallmark feature of the lolines, which is uncommon in organic compounds—joining two distant ring (C-2 and C-7) carbons (see Fig. 1). Different substituents at the C-1 amine, such as methyl, formyl, and acetyl groups, yield loline species that have variable bioactivity against insects. Besides endophyte–grass symbionts, loline alkaloids have also been identified in some other plant species; namely, "Adenocarpus" species (family Fabaceae) and "Argyreia mollis" (family Convolvulaceae). | https://en.wikipedia.org/wiki?curid=22802306 | 1,884,720 |
870,535 | Despite the benefit to Acorn of expanding its customer base, dissatisfaction was expressed by dealers and software companies about the effects of the scheme, with anecdotes emerging of a reluctance to buy equipment that could be obtained for free, thus harming dealer revenues, although Acorn's education marketing manager argued that the scheme's effect was generally positive and actually produced sales opportunities for dealers. The inclusion of software products in the scheme was regarded by one commentator as harmful to both the companies whose products were featured, these "not making enough profit from the transaction", and to those whose products were not, these seeing potential customers choose their competitors' "free" products. Noting that the scheme was "not purely philanthropic", concern was expressed about the effect on the Acorn market and that schools were needing to "resort to charities and publicity stunts to get the basic tools to do the job". In response to such criticism, independent software titles were dropped from the scheme in 1994, which ultimately distributed products to over 10,000 schools including 4,000 computers, with a total of 15,000 computers having been given away over the first three years of the scheme. | https://en.wikipedia.org/wiki?curid=63145 | 870,075 |
1,397,360 | The company's literature claimed that its chairman had a doctorate and a master's degree; an investigation showed that he had neither. Barrington also claimed accreditation by the International Association of Universities and Schools Inc. (IAUS). However, a 2003 investigation by the "South Florida Business Journal" revealed this was a for-profit corporation set up in Florida (not Switzerland or Washington, D.C., as claimed) by Virtual Academics' chairman, Robert Bettinger, and the owner of another for-profit college in 1998. According to the "New York Post", they did this to avoid further problems due to their schools' lack of accreditation. The IAUS' charter was subsequently dissolved by the State of Florida for failure to pay annual registration fees. The "South Florida Business Journal" also reported that Barrington was paying professors and schools in China commissions to sell Barrington degrees to Chinese students; this revelation caused a major drop in Chinese enrollments and a resulting decline in revenues. | https://en.wikipedia.org/wiki?curid=20733060 | 1,396,587 |
2,025,919 | Eliminating the MTH1 gene in mice results in over three times more mice developing tumors compared to a control group. The enzyme's much-studied ability to sanitize a cell's nucleotide pool prevents it from developing mutations, including cancerous ones. Specifically, another study found that MTH1 inhibition in cancer cells leads to incorporation of 8-oxo-dGTP and other oxidatively damaged nucleotides into the cell's DNA, damaging it and causing cell death. However, cancer cells have also been shown to benefit from use of MTH1. Cells from malignant breast tumors exhibit extreme MTH1 expression compared to other human cells. Because a cancer cell divides much more rapidly than a normal human cell, it is far more in need of an enzyme like MTH1 that prevents fatal mutations during replication. This property of cancer cells could allow for monitoring of cancer treatment efficacy by measuring MTH1 expression. Development of suitable probes for this purpose is currently underway. | https://en.wikipedia.org/wiki?curid=39383381 | 2,024,753 |
190,561 | In 1914, he attempted to enter the army on August 16, and then again in October, but was refused due to poor eyesight. Banting successfully joined the army in 1915 and spent the summer training before returning to school. His class was fast-tracked to get more doctors into the war and so he graduated in December 1916 and reported for military duty the next day. He was wounded at the Battle of Cambrai in 1918. Despite his injuries, he helped other wounded men for sixteen hours, until another doctor told him to stop. He was awarded the Military Cross in 1919, for heroism. In 1918, he was awarded the license to practise medicine, surgery, and midwifery by the Royal College of Physicians of London. | https://en.wikipedia.org/wiki?curid=75076 | 190,462 |
97,366 | Moscovium is an extremely radioactive element: its most stable known isotope, moscovium-290, has a half-life of only 0.65 seconds. In the periodic table, it is a p-block transactinide element. It is a member of the 7th period and is placed in group 15 as the heaviest pnictogen, although it has not been confirmed to behave as a heavier homologue of the pnictogen bismuth. Moscovium is calculated to have some properties similar to its lighter homologues, nitrogen, phosphorus, arsenic, antimony, and bismuth, and to be a post-transition metal, although it should also show several major differences from them. In particular, moscovium should also have significant similarities to thallium, as both have one rather loosely bound electron outside a quasi-closed shell. Over a hundred atoms of moscovium have been observed to date, all of which have been shown to have mass numbers from 286 to 290. | https://en.wikipedia.org/wiki?curid=67514 | 97,325 |
1,381,181 | array processing concept was closely linked to radar and sonar systems which represent the classical applications of array processing. The antenna array is used in these systems to determine location(s) of source(s), cancel interference, suppress ground clutter. Radar systems used basically to detect objects by using radio waves. The range, altitude, speed and direction of objects can be specified. Radar systems started as military equipments then entered the civilian world. In radar applications, different modes can be used, one of these modes is the active mode. In this mode the antenna array based system radiates pulses and listens for the returns. By using the returns, the estimation of parameters such as velocity, range and DOAs (direction of arrival) of target of interest become possible. Using the passive far-field listening arrays, only the DOAs can be estimated. Sonar systems (Sound Navigation and Ranging) use the sound waves that propagate under the water to detect objects on or under the water surface. Two types of sonar systems can be defined the active one and the passive one. In active sonar, the system emits pulses of sound and listens to the returns that will be used to estimate parameters. In the passive sonar, the system is essentially listening for the sounds made by the target objects. It is very important to note the difference between the radar system that uses radio waves and the sonar system that uses sound waves, the reason why the sonar uses the sound wave is because sound waves travel farther in the water than do radar and light waves. In passive sonar, the receiving array has the capability of detecting distant objects and their locations. Deformable array are usually used in sonar systems where the antenna is typically drawn under the water. In active sonar, the sonar system emits sound waves (acoustic energy) then listening and monitoring any existing echo (the reflected waves). The reflected sound waves can be used to estimate parameters, such as velocity, position and direction etc. Difficulties and limitations in sonar systems comparing to radar systems emerged from the fact that the propagation speed of sound waves under the water is slower than the radio waves. Another source of limitation is the high propagation losses and scattering. Despite all these limitations and difficulties, sonar system remains a reliable technique for range, distance, position and other parameters estimation for underwater applications. | https://en.wikipedia.org/wiki?curid=1326926 | 1,380,418 |
1,367,566 | The difficulty with this theory is that in typical non-lesioned subjects, locations within the brain anatomy are similar but not completely identical. There is a strong defense for this inherent deficit in our ability to generalize when using functional localizing techniques (fMRI, PET etc.). To account for this problem, the coordinate-based "Talairach and Tournoux stereotaxic system" is widely used to compare subjects' results to a standard brain using an algorithm. Another solution using coordinates involves comparing brains using sulcal reference points. A slightly newer technique is to use functional landmarks, which combines sulcal and gyral landmarks (the groves and folds of the cortex) and then finding an area well known for its modularity such as the fusiform face area. This landmark area then serves to orient the researcher to the neighboring cortex. | https://en.wikipedia.org/wiki?curid=25146378 | 1,366,810 |
1,583,527 | Each particular combination of construction materials and design features has practical limits with respect to temperature, differential pressure, speed, applied loads and operating environment; however, these limits can generally be overcome by carefully selecting or designing the device for the application. Necessary features may include multiple ferrofluid stages, water cooling, customized materials including metals, permanent magnets and ferrofluid, and exotic bearings. Ferrofluid-based seals have extremely low leak rates - almost immeasurable with laboratory equipment - however they cannot reach the levels of welded connections or other all-metal, static (non-rotating) seals. | https://en.wikipedia.org/wiki?curid=8573560 | 1,582,637 |
1,639,119 | Cellulosomes are multi-enzyme extracellular complexes. Cellulosomes are associated with the cell surface and mediate cell attachment to insoluble substrates and degrade them to soluble products which are then absorbed. Cellulosome complexes are intricate, multi-enzyme machines, produced by many cellulolytic microorganisms. They are produced by microorganisms for efficient degradation of plant cell wall polysaccharides, notably cellulose, the most abundant organic polymer on Earth. The multiple subunits of cellulosomes are composed of numerous functional domains that interact with each other and with the cellulosic substrate. One of these subunits, a large glycoprotein "scaffoldin", is a distinctive class of non-catalytic scaffolding polypeptides. The scaffoldin subunit selectively integrates the various cellulases and xylanase subunits into the cohesive complex, by combining its cohesin domains with a typical dockerin domain present on each of the subunit enzymes. The scaffoldin of some cellulosomes, an example being that of "Clostridium thermocellum", contains a carbohydrate-binding module that adheres cellulose to the cellulosomal complex. | https://en.wikipedia.org/wiki?curid=5559797 | 1,638,194 |
1,509,905 | Meta-analyses have been able to identify additional associated genes, by pooling a number of large gene datasets. This successful study illustrates the importance of compiling and sharing large genome databases. The inclusion of phenotypic data in these databases will enhance discovery of candidate genes, while the addition of environmental and temporal data should be able to advance the disease progression pathways knowledge. HUGENet, which was initiated by the Centers for Disease Control and Prevention (U.S.), is accomplishing the integration of this type of information with the genome data, in a form available for analysis. This project could be thought of as an example of 'metagenomics', the analysis of a community's genome, but for a human rather than a microbial community. This project is intended to promote international data sharing and collaboration, in addition to creating a standard and framework for the collection of this data. | https://en.wikipedia.org/wiki?curid=8767449 | 1,509,055 |
314,024 | Improved precision landing technology that enhances the scientific value of robotic missions also will be critical for eventual human exploration on the surface. Based on input from the Science Definition Team, NASA defined the final objectives for the 2020 rover. Those became the basis for soliciting proposals to provide instruments for the rover's science payload in the spring of 2014. The mission will also attempt to identify subsurface water, improve landing techniques, and characterize weather, dust, and other potential environmental conditions that could affect future astronauts living and working on Mars. | https://en.wikipedia.org/wiki?curid=37837437 | 313,855 |
855,153 | For example, (using the first formula (1) for absolute maximum breathing time), a diver at a depth of 15 meters in water with an average density of 1020 kg/m (typical seawater), who breathes at a rate of 20 litres per minute, using a dive cylinder of 18 litres pressurized at 200 bars, can breathe for a period of 72 minutes before the cylinder pressure falls so low as to prevent inhalation. In some open circuit scuba systems this can happen quite suddenly, from a normal breath to the next abnormal breath, a breath which may not be fully drawn. (There is never any difficulty exhaling). The suddenness of this effect depends on the design of the regulator and the internal volume of the cylinder. In such circumstances there remains air under pressure in the cylinder, but the diver is unable to breathe it. Some of it can be breathed if the diver ascends, as the ambient pressure is reduced, and even without ascent, in some systems a bit of air from the cylinder is available to inflate buoyancy compensator devices (BCDs) even after it no longer has pressure enough to open the demand valve. | https://en.wikipedia.org/wiki?curid=460321 | 854,698 |
182,071 | In addition to very low gain of about 5 and a short lifetime of about 30 – 100 hours, the primitive Audion had erratic characteristics because it was incompletely evacuated. De Forest believed that ionization of residual air was key to Audion operation. This made it a more sensitive detector but also caused its electrical characteristics to vary during use. As the tube heated up, gas released from the metal elements would change the pressure in the tube, changing the plate current and other characteristics, so it required periodic bias adjustments to keep it at the correct operating point. Each Audion stage usually had a rheostat to adjust the filament current, and often a potentiometer or multiposition switch to control the plate voltage. The filament rheostat was also used as a volume control. The many controls made multitube Audion receivers complicated to operate. | https://en.wikipedia.org/wiki?curid=491851 | 181,975 |
502,065 | In MDDS associated with mutations in "POLG" that primarily affect the brain and the liver, the symptoms are very diverse and can emerge anytime from shortly after birth to old age. The first signs of the disease, which include intractable seizures and failure to meet meaningful developmental milestones, usually occur in infancy, after the first year of life, but sometimes as late as the fifth year. Primary symptoms of the disease are developmental delay, progressive intellectual disability, hypotonia (low muscle tone), spasticity (stiffness of the limbs) possibly leading to quadriplegia, and progressive dementia. Seizures may include epilepsia partialis continua, a type of seizure that consists of repeated myoclonic (muscle) jerks. Optic atrophy may also occur, often leading to blindness. Hearing loss may also occur. Additionally, although physical signs of chronic liver dysfunction may not be present, many people experience liver impairment leading to liver failure. | https://en.wikipedia.org/wiki?curid=42392931 | 501,807 |
2,246,951 | Current research regarding Botrytis-induced kinase1 aims to determine how BIK1 interacts with MAPK pathway proteins as well as with the OXI1 kinase. Also, studies are being conducted to determine the relationship between BIK1 and the phosphorylizing homolog kinases PEPR1 and PEPR2. Though it is believed that PEPR1 and PEPR2 act as enzymes toward BIK1 and phosphorylate the kinase, research is still being done to examine the effects of the interaction on a broader scale. Previously published research suggests that PEPR1 and PEPR2 work with the ET signal pathway and Botrytis-induced kinase1 in order to amplify the defense mechanism in immune response. Additionally, future research may explore the mechanism that allows BIK1 and BAK1 to cooperate with the FLS2 receptor to initiate defense response. While it is known that the three work together and each is required for the process to occur efficiently, but the exact relationship between the three remains unknown and the specific binding residues for each component have yet to be determined "in vivo". | https://en.wikipedia.org/wiki?curid=54992251 | 2,245,679 |
380,963 | "The easy availability of replacement labor, which allowed Taylor to choose only 'first-class men,' was an important condition for his system's success." The situation in the Soviet Union was very different. "Because work is so unrhythmic, the rational manager will hire more workers than he would need if supplies were even in order to have enough for storming. Because of the continuing labor shortage, managers are happy to pay needed workers more than the norm, either by issuing false job orders, assigning them to higher skill grades than they deserve on merit criteria, giving them 'loose' piece rates, or making what is supposed to be 'incentive' pay, premia for good work, effectively part of the normal wage. As Mary McAuley has suggested under these circumstances piece rates are not an incentive wage, but a way of justifying giving workers whatever they 'should' be getting, no matter what their pay is supposed to be according to the official norms." | https://en.wikipedia.org/wiki?curid=204995 | 380,768 |
1,814,306 | These include analysis of the extreme anterior domain (EAD), a unique and important embryonic region she named. She used a simple anterior organ, the mucus-secreting cement gland of the frog Xenopus, to define the genetic network required for anterior position. The EAD also gives rise to the mouth and the Sive group has defined key steps necessary for mouth formation. Using their ‘facial transplant’ technique, her group made the unprecedented discovery that the EAD is also a facial signaling center, which guides neural crest cells into the developing face, where they form the jaws and other structures. Since the EAD is present in humans, the work is directly relevant for understanding human craniofacial anomalies. | https://en.wikipedia.org/wiki?curid=55890626 | 1,813,272 |
26,854 | The focus of much CF gene therapy research is aimed at trying to place a normal copy of the "CFTR" gene into affected cells. Transferring the normal "CFTR" gene into the affected epithelium cells would result in the production of functional CFTR protein in all target cells, without adverse reactions or an inflammation response. To prevent the lung manifestations of CF, only 5–10% the normal amount of CFTR gene expression is needed. Multiple approaches have been tested for gene transfer, such as liposomes and viral vectors in animal models and clinical trials. However, both methods were found to be relatively inefficient treatment options, mainly because very few cells take up the vector and express the gene, so the treatment has little effect. Additionally, problems have been noted in cDNA recombination, such that the gene introduced by the treatment is rendered unusable. There has been a functional repair in culture of CFTR by CRISPR/Cas9 in intestinal stem cell organoids of cystic fibrosis patients. | https://en.wikipedia.org/wiki?curid=50601 | 26,844 |
807,499 | Like the other "Convolvulus" bindweeds of Eurasia, it is specifically pollinated by sweat bees in the genus "Systropha". These are specialists (oligolectic) feeding upon the flowers of these plants, possessing unusual modifications of the scopa, such that almost the entire abdomen (including the dorsal surface) is used for carrying pollen, rather than the legs, as in most bees. Species of "Systropha" in central Europe (such as "S. curvicornis" and "S. planidens", both uncommon bees) are essentially entirely dependent upon "C. arvensis". Although both species specialise on the same plant species, "S. curvicornis" is a habitat generalist while "S. planidens" is only found in steppe habitats, although they are also found occurring together. The males of both species claim territories consisting of a patch of bindweed flowers, perching on the flowers in the afternoon after a regular patrol of their little patch for errant conspecific males, which, upon countenance, they proceed to attack the intruder by ramming him from the air with a specialised protuberance on their lower abdomen. Sometimes bumblebees, honey bees or other insects are air-bombed, but never rammed. The males retreat inside the flower after the perching session, as it closes in the late afternoon, spending the night inside the flower and escaping at dawn before or after it fully closes (the females stay in underground tunnel nests). The males only land on flowers (sometimes of other plants), eschewing other perches, and feed on the nectar. Females forage for nectar and pollen in the morning and early afternoon while flowers stay open. Most copulation occurs in bindweed flowers: when a virgin female wanders into their patch, and the larger males find them busy at one of their flowers during morning patrol, the males pounce upon them without ado and immediately establish contact with their mutual genitalia, getting the job done on average 90 seconds later. These species are themselves specifically parasitised upon by the cuckoo bee "Biastes brevicornis". | https://en.wikipedia.org/wiki?curid=4954263 | 807,069 |
1,275,762 | In 1854, Kelvin produced a mathematical description of retardation by analogy with heat flow after the fiasco with the first transatlantic cable. In 1881, Oliver Heaviside gave the full analysis of transmission lines which described how the problem arose and suggested how it could be resolved n 1887. Heaviside believed that adding the right amount of inductance to the line would completely remove the dispersion effect. He tried to persuade the General Post Office (the Post Office) to take up the idea, but as an outsider—and considered a maverick—he was ignored, largely because of his long-running dispute with William Preece, the Post Office chief electrician (chief engineer). It was left to George Ashley Campbell in the US to implement the idea when he added loading coils to a telephone line for the first time in 1900. | https://en.wikipedia.org/wiki?curid=60245762 | 1,275,069 |
380,272 | Galton was a keen observer. In 1906, visiting a livestock fair, he stumbled upon an intriguing contest. An ox was on display, and the villagers were invited to guess the animal's weight after it was slaughtered and dressed. Nearly 800 participated, and Galton was able to study their individual entries after the event. Galton stated that "the middlemost estimate expresses the "vox populi", every other estimate being condemned as too low or too high by a majority of the voters", and reported this value (the median, in terminology he himself had introduced, but chose not to use on this occasion) as 1,207 pounds. To his surprise, this was within 0.8% of the weight measured by the judges. Soon afterwards, in response to an enquiry, he reported the mean of the guesses as 1,197 pounds, but did not comment on its improved accuracy. Recent archival research has found some slips in transmitting Galton's calculations to the original article in "Nature": the median was actually 1,208 pounds, and the dressed weight of the ox 1,197 pounds, so the mean estimate had zero error. James Surowiecki uses this weight-judging competition as his opening example: had he known the true result, his conclusion on the wisdom of the crowd would no doubt have been more strongly expressed. | https://en.wikipedia.org/wiki?curid=49072 | 380,077 |
40,610 | The World Health Organization has identified hypertension, or high blood pressure, as the leading cause of cardiovascular mortality. The World Hypertension League (WHL), an umbrella organization of 85 national hypertension societies and leagues, recognized that more than 50% of the hypertensive population worldwide are unaware of their condition. To address this problem, the WHL initiated a global awareness campaign on hypertension in 2005 and dedicated May 17 of each year as World Hypertension Day (WHD). Over the past three years, more national societies have been engaging in WHD and have been innovative in their activities to get the message to the public. In 2007, there was record participation from 47 member countries of the WHL. During the week of WHD, all these countries – in partnership with their local governments, professional societies, nongovernmental organizations and private industries – promoted hypertension awareness among the public through several media and public rallies. Using mass media such as Internet and television, the message reached more than 250 million people. As the momentum picks up year after year, the WHL is confident that almost all the estimated 1.5 billion people affected by elevated blood pressure can be reached. | https://en.wikipedia.org/wiki?curid=77432 | 40,595 |
2,101,328 | CSSWE underwent the same rigorous testing that all space-based assets at LASP do. In addition to component and subsystem level testing, the spacecraft underwent numerous system level tests. It passed the thermal vacuum chamber test, in which 11 orbital cycles of the spacecraft were simulated in vacuum by increasing and decreasing the spacecraft temperature to reproduce thermal models which predict actual on-orbit temperatures. The first few hours of the mission were reproduced by simulating launch (in which the deployment switch is released, initiating automated commissioning phase) from a mesa nearby the LASP ground station. CSSWE passed this test by completing the initial commissioning phase, deploying its antenna, and establishing contact with the LASP ground station. Orbital attitude tests were performed as well, including Helmholtz cage and error ellipse tests. | https://en.wikipedia.org/wiki?curid=34484004 | 2,100,117 |
727,425 | Other bearing designs are often better on one specific attribute, but worse in most other attributes, although fluid bearings can sometimes simultaneously outperform on carrying capacity, durability, accuracy, friction, rotation rate and sometimes cost. Only plain bearings are used as widely as rolling-element bearings. Common mechanical components where they are widely used are - automotive, industrial, marine, and aerospace applications. They are products of great necessity for modern technology. The rolling element bearing was developed from a firm foundation that was built over thousands of years. The concept emerged in its primitive form in Roman times; after a long inactive period in the Middle Ages, it was revived during the Renaissance by Leonardo da Vinci, developed steadily in the seventeenth and eighteenth centuries. | https://en.wikipedia.org/wiki?curid=627542 | 727,043 |
225,352 | According to Christopher Lipinski and Andrew Hopkins, "Whether the aim is to discover drugs or to gain knowledge of biological systems, the nature and properties of a chemical tool cannot be considered independently of the system it is to be tested in. Compounds that bind to isolated recombinant proteins are one thing; chemical tools that can perturb cell function another; and pharmacological agents that can be tolerated by a live organism and perturb its systems are yet another. If it were simple to ascertain the properties required to develop a lead discovered "in vitro" to one that is active "in vivo", drug discovery would be as reliable as drug manufacturing." Studies on "In vivo" behavior, determined the formulations of set specific drugs and their habits in a Biorelevant (or Biological relevance) medium. | https://en.wikipedia.org/wiki?curid=15187 | 225,236 |
182,245 | The La ion is similarly sized to the early lanthanides of the cerium group (those up to samarium and europium) that immediately follow in the periodic table, and hence it tends to occur along with them in phosphate, silicate and carbonate minerals, such as monazite (MPO) and bastnäsite (MCOF), where M refers to all the rare earth metals except scandium and the radioactive promethium (mostly Ce, La, and Y). Bastnäsite is usually lacking in thorium and the heavy lanthanides, and the purification of the light lanthanides from it is less involved. The ore, after being crushed and ground, is first treated with hot concentrated sulfuric acid, evolving carbon dioxide, hydrogen fluoride, and silicon tetrafluoride: the product is then dried and leached with water, leaving the early lanthanide ions, including lanthanum, in solution. | https://en.wikipedia.org/wiki?curid=17744 | 182,149 |
364,274 | As she neared the end of her doctorate in 1924, Irène Curie was asked to teach the precision laboratory techniques required for radiochemical research to the young chemical engineer Frédéric Joliot, whom she would later wed. From 1928 Joliot-Curie and her husband Frédéric combined their research efforts on the study of atomic nuclei. In 1932, Joliot-Curie and her husband Frédéric had full access to Marie's polonium. Experiments were done using gamma rays to identify the positron. Though their experiments identified both the positron and the neutron, they failed to interpret the significance of the results and the discoveries were later claimed by Carl David Anderson and James Chadwick respectively. These discoveries would have secured greatness indeed, as together with J. J. Thomson's discovery of the electron in 1897, they finally replaced John Dalton's model of atoms as solid spherical particles. | https://en.wikipedia.org/wiki?curid=62070 | 364,084 |
1,531,981 | The Gophers opened the second half of their season with a sweep over lowly Michigan State but then suffered a massive loss. On January 9th Jack LaFontaine, who had played all but 28 minutes in goal for the team to that point, signed a profession contract with the Carolina Hurricanes and ended his college career. Minnesota was forced to turn to junior Justen Close, who hadn't started a game in three years. The defense rallied around the Saskatchewan native and kept him insulated for several games as he got used to his new role on the team. Close managed to break even for the remainder of January even while playing two tournament-bound teams. | https://en.wikipedia.org/wiki?curid=68636060 | 1,531,114 |
533,292 | ZSM-5 is composed of several pentasil units linked together by oxygen bridges to form pentasil chains. A pentasil unit consists of eight five-membered rings. In these rings, the vertices are Al or Si and an O is assumed to be bonded between the vertices. The pentasil chains are interconnected by oxygen bridges to form corrugated sheets with 10-ring holes. Like the pentasil units, each 10-ring hole has Al or Si as vertices with an O assumed to be bonded between each vertex. Each corrugated sheet is connected by oxygen bridges to form a structure with "straight 10-ring channels running parallel to the corrugations and sinusoidal 10-ring channels perpendicular to the sheets." Adjacent layers of the sheets are related by an inversion point. The estimated pore size of the channel running parallel with the corrugations is 5.4–5.6 Å. The crystallographic unit cell of ZSM-5 has 96 T sites (Si or Al), 192 O sites, and a number of compensating cations depending on the Si/Al ratio, which ranges from 12 to infinity. The structure is orthorhombic (space group Pnma) at high temperatures, but a phase transition to the monoclinic space group P2/n.1.13 occurs on cooling below a transition temperature, located between 300 and 350 K. | https://en.wikipedia.org/wiki?curid=17162404 | 533,013 |
1,988,566 | Cantlon studied anthropology at Indiana University Bloomington. She moved to Duke University for her graduate studies, where she worked with Elizabeth Brannon on the neural bases of mathematical knowledge. Early in her graduate studies, Cantlon trained herself in functional MRI, recognising that neuroimaging could be used to further our understanding of learning. Her research involved investigations into the origin of the human and primate capacity for mathematics. Cantlon showed that monkeys can perform mental arithmetic. Working with Brannon, Cantlon constructed a mathematical task that asked monkeys to deduce whether a series of numbers were larger or smaller than the ones that proceeded them. This study showed that the mechanism that monkeys use to make comparisons are the same as the ones humans use. To prove the numerical skills of monkeys, Cantlon constructed an experiment where macaques interacted with a touchscreen computer that displayed basic mathematical challenges. Cantlon presented the same challenges to college students, who achieved 94% correct answers, whilst the monkeys were successful 76% of the time. The monkeys and college students had the same reaction time. She completed her doctorate in 2007. | https://en.wikipedia.org/wiki?curid=63266692 | 1,987,424 |
1,123,436 | T-cell immune receptors are important in seeing the world of pathogens in the cellular immune system. One of the reasons for sequencing the human and mouse TCR loci was to match the orthologous gene family sequences and discover conserved areas using comparative genomics. These, it was thought, would reflect two sorts of biological information: (1) exons and (2) regulatory sequences. In fact, the majority of V, D, J, and C exons could be identified in this method. The variable regions are encoded by multiple unique DNA elements that are rearranged and connected during T cell (TCR) differentiation: variable (V), diversity (D), and joining (J) elements for the and polypeptides; and V and J elements for the and polypeptides.[Figure 1] However, several short noncoding conserved blocks of the genome had been shown. Both human and mouse motifs are largely clustered in the 200 bp [Figure 2], the known 3′ enhancers in the TCR/ were identified, and a conserved region of 100 bp in the mouse J intron was subsequently shown to have a regulatory function. | https://en.wikipedia.org/wiki?curid=917868 | 1,122,862 |
48,776 | In unsupervised learning, input data is given along with the cost function, some function of the data formula_1 and the network's output. The cost function is dependent on the task (the model domain) and any "a priori" assumptions (the implicit properties of the model, its parameters and the observed variables). As a trivial example, consider the model formula_2 where formula_3 is a constant and the cost formula_4. Minimizing this cost produces a value of formula_3 that is equal to the mean of the data. The cost function can be much more complicated. Its form depends on the application: for example, in compression it could be related to the mutual information between formula_1 and formula_7, whereas in statistical modeling, it could be related to the posterior probability of the model given the data (note that in both of those examples those quantities would be maximized rather than minimized). Tasks that fall within the paradigm of unsupervised learning are in general estimation problems; the applications include clustering, the estimation of statistical distributions, compression and filtering. | https://en.wikipedia.org/wiki?curid=21523 | 48,756 |
498,084 | Since classical analog filters are IIR filters, there has been a long history of studying the range of possible transfer functions implementing various of the above desired filter responses in continuous time systems. Using transforms it is possible to convert these continuous time frequency responses to ones that are implemented in discrete time, for use in digital IIR filters. The complexity of any such filter is given by the "order" N, which describes the order of the rational function describing the frequency response. The order N is of particular importance in analog filters, because an N order electronic filter requires N reactive elements (capacitors and/or inductors) to implement. If a filter is implemented using, for instance, biquad stages using op-amps, N/2 stages are needed. In a digital implementation, the number of computations performed per sample is proportional to N. Thus the mathematical problem is to obtain the best approximation (in some sense) to the desired response using a smaller N, as we shall now illustrate. | https://en.wikipedia.org/wiki?curid=9975 | 497,827 |
1,883,015 | Any thermoacoustic imaging device requires a source of electromagnetic radiation, be it a laser or a microwave antenna, to deliver energy to the anatomy being studied, and one or more acoustic detectors coupled acoustically to the outside surface of the anatomy, as is illustrated in Fig. 4. The typical acoustic detector is an ultrasound transducer, which is commonly made of a piezo-electric material that converts detected pressure to an electrical signal. Thermoacoustic waves are induced within the anatomy wherever absorption takes place, and the strength of these thermoacoustic waves is proportional to the energy absorbed within the tissue. Some of these waves propagate through the anatomy over some time interval ("time-of-flight") before being detected by one or more of the acoustic transducers. The exact time-of-flight is proportional to the distance between an absorption site and a transducer, assuming for the moment that each transducer is a "point" detector. For any given time-of-flight, each transducer will receive the sum of the thermoacoustic waves originating at the same distance from the detector in question as is illustrated in Fig. 5. For this reason, ambiguity arises when attempting to localize an absorption site with a point transducer. A variety of strategies have been employed to mitigate this ambiguity. | https://en.wikipedia.org/wiki?curid=19820084 | 1,881,934 |
1,996,567 | After receiving an AB in applied mathematics "magna cum laude" from Harvard College in 1970, he received an M.D. (1976) and Ph.D. in Medical Information Systems (1975) from Stanford University, with a dissertation on the MYCIN system, for which he also won the 1976 Grace Murray Hopper Award for outstanding computer scientists under the age of 30. He completed internal medicine house-staff training from 1976-1979 at Massachusetts General Hospital and Stanford Hospital. In 1979 he joined the Stanford faculty in internal medicine and computer science, where he directed the Stanford University Medical EXpertimental computer resource (SUMEX) and subsequently the Center for Advanced Medical Informatics at Stanford (CAMIS), continuing his work on expert systems, including ONCOCIN (an oncology decision support program), T-HELPER, and other projects in the Stanford Heuristic Programming Project. He also simultaneously served as chief of general internal medicine and associate chair of medicine for primary care, and was principal investigator of the InterMed Collaboratory, which developed the science of computable guidelines for medical decision support. | https://en.wikipedia.org/wiki?curid=9800360 | 1,995,424 |
1,725,772 | The separation of a sound into ENV and TFS appears inspired partly by how sounds are synthesized and by the availability of a convenient way to separate an existing sound into ENV and TFS, namely the Hilbert transform. There is a risk that this view of auditory processing is dominated by these physical/technical concepts, similarly to how cochlear frequency-to-place mapping was for a long time conceptualized in terms of the Fourier transform. Physiologically, there is no indication of a separation of ENV and TFS in the auditory system for stages up to the cochlear nucleus. Only at that stage does it appear that parallel pathways, potentially enhancing ENV or TFS information (or something akin to it), may be implemented through the temporal response characteristics of different cochlear nucleus cell types. It may therefore be useful to better simulate cochlear nucleus cell types to understand the true concepts for parallel processing created at the level of the cochlear nucleus. These concepts may be related to separating ENV and TFS but are unlikely realized like the Hilbert transform. | https://en.wikipedia.org/wiki?curid=56439577 | 1,724,801 |
1,180,531 | The improvement of mechanical properties and thermal stability is and has always been an important goal in the research of new plastics. Since the early 1960s, the development of high-performance plastics has been driven by corresponding needs in the aerospace and nuclear technology. Synthetic routes for example for PPS, PES and PSU were developed in the 1960s by Philips, ICI and Union Carbide. The market entry took place in the early 70s. A production of PEEK (ICI), PEK (ICI) and PEI (General Electric and GE) via polycondensation was developed in the 1970s. PEK was offered since 1972 by Raychem, however, made by an electrophilic synthesis. Since electrophilic synthesis has in general the disadvantage of a low selectivity to linear polymers and is using aggressive reactants, the product could hold only a short time on the market. For this reason, the majority of high-performance plastics is nowadays produced by polycondensation processes. | https://en.wikipedia.org/wiki?curid=41997466 | 1,179,907 |
1,821,985 | Drawing on earlier research that indicated the presence of phosphoglycolic acid in algae through labeling of CO and P-orthophosphate, Richardson & Tolbert were the first to find a phosphatase activity specific for phosphoglycolate in tobacco leaves. The pH optimum of the enzyme is 6.3, and Mg or Mn ions as cofactors were necessary for activity. Mg has been consistently noted to yield the maximum turnover rate. In other studies, Co could also act as a divalent cofactor. In addition, Ca, despite being divalent, inhibits phosphoglycolate phosphatase on levels of greater than 90% of its enzymatic activity by acting as a competitive inhibitor to Mg. Finally, Cl can activate at low concentrations (up to 50mM), but at high concentrations, chloride ions will act as competitive inhibitors with respect to phosphoglycolate. The enzyme localizes to the chloroplast, and plant studies, involving CO fixation in the light, identified labeled glycolate outside of the chloroplast, suggesting that the activity of phosphoglycolate phosphatase allows the movement of glycolate out of the chloroplast. | https://en.wikipedia.org/wiki?curid=14457357 | 1,820,947 |
1,948,307 | Braatz graduated from Oregon State University with a B.S. in 1988 with an undergraduate thesis on heat exchanger design supervised by Octave Levenspiel. He worked at Chevron Research and Avery Dennison before receiving his M.S. and Ph.D. in robust control from the California Institute of Technology under the direction of Professor Manfred Morari. His thesis included a proof that robust control problems are NP-hard. After a postdoctoral year at DuPont, he moved to the University of Illinois at Urbana-Champaign, where he rose to the position of Millennium Chair and Professor, with positions in Chemical and Biomolecular Engineering, Electrical and Computer Engineering, Mechanical Science and Engineering, Bioengineering, Applied Mathematics, and Computational Science and Engineering. Braatz made contributions in the areas of robust optimal control, fault detection and diagnosis, sheet and film processes, and crystallization. | https://en.wikipedia.org/wiki?curid=22845121 | 1,947,194 |
954,692 | The position of rector was established by Parliament in 1905 following the Dissolution of the Union. Waldemar Christofer Brøgger was Professor of Geology and became the university's first rector. Brøgger vacillated between a certain pessimism and a powerfully energetic attitude regarding how to procure finances for research and fulfill his more general funding objectives. With the establishment of the national research council after World War II, Brøgger's vision was largely fulfilled; research received funding independent of teaching. This coincided with a massive rise in student enrollment during the 1960s, which again made it difficult to balance research with the demands for teaching. In the years leading up to 1940, research was more strongly linked with the growth of the nation, with progress and self-assertion; research was also seen to contribute to Norway's commitment to international academic and cultural development. | https://en.wikipedia.org/wiki?curid=31800 | 954,187 |
162,762 | In Feb 2018, the Trump administration's proposed a FY2019 budget that would have delayed the funding of the Roman (then called WFIRST), citing higher priorities within NASA and the increasing cost of this telescope. The proposed defunding of the project was met with criticism by professional astronomers, who noted that the American astronomical community had rated Roman the highest-priority space mission for the 2020s in the 2010 Decadal Survey. The American Astronomical Society expressed "grave concern" about the proposed defunding, and noted that the estimated lifecycle cost for Roman had not changed over the previous two years. However, on 22-23 March 2018, Congress approved a FY18 Roman budget in excess of the administration's budget request for that year and stated that Congress "rejects the cancellation of scientific priorities recommended by the National Academy of Sciences decadal survey process", and further directed NASA to develop new estimates of Roman's total and annual development costs. Later, the President announced he had signed the bill on 23 March 2018. NASA was funded via a FY2019 appropriations bill on February 15, 2019, with US$312 million for Roman, rejecting the President's reduced Budget Request and reasserting the desire for completion of Roman with a planning budget of US$3.2 billion. | https://en.wikipedia.org/wiki?curid=28371067 | 162,677 |
736,186 | Things got worse for the NFL when investigative reporters Steve Fainaru and his brother Mike Fainaru-Wada learned from an anonymous source that the NFL Retirement Board had awarded "disability payments to at least three former players after concluding that football caused their crippling brain injuries – even as the league's top medical experts for years consistently denied any link between the sport and long-term brain damage." One of the cases was that of Mike Webster, who filed a claim in 1999. In 2005, three years after his death, his family received $1.8 million from the Retirement Board. "That same year," write the Fainuru brothers, "the NFL published the 10th installment in its series on concussions research in the medical journal "Neurosurgery." The paper, whose authors included three members of the League's [MTBI], asserted that chronic brain injury 'has never been reported in American football players.'" | https://en.wikipedia.org/wiki?curid=36082813 | 735,799 |
1,917,393 | In 1976 he took up an appointment in Canberra, Australia at the Department of Anthropology in the Research School of Pacific Studies, Australian National University. He undertook filming everyday interaction in Papua New Guinea but also was able to record a sign language in use in the valley where he worked where there was a considerable number of deaf persons. His publication of this work, in three articles in 1980, proved to be a pioneering study; no other accounts on sign language from this part of the world were to appear until the beginning of the twenty-first century. This work was republished as a monograph together with a new essay written by colleagues bringing the original work up to date. After this he undertook a major investigation of the sign languages in use among indigenous Australians - these are sign languages used for ritual reasons or for practical reasons in situations where speech might is impractical or inappropriate. These are known as alternate sign languages, distinguishing them from primary sign languages developed among deaf people. Extensive documentation of his research in Australia is available at the library of the Australian Institute of Aboriginal and Torres Strait Islander Studies. | https://en.wikipedia.org/wiki?curid=2072724 | 1,916,293 |
610,133 | Fuller's teasel (the cultivar group "Dipsacus fullonum" Sativus Group; syn. "D. sativus") historically saw wide use in textile processing, providing a natural comb for cleaning, aligning and raising the nap on fabrics, particularly wool. The product of the teasing process is called teased wool. The cultivar differs from the wild type in having stouter, somewhat recurved spines on the seed heads. The dried flower heads were attached to spindles, wheels, or cylinders, sometimes called teasel frames, to raise the nap on fabrics (that is, to tease the fibres). By the 20th century, teasels had been largely replaced by metal cards, which can be made uniformly and do not require constant replacement as the teasel heads wear. However, some people who weave wool still prefer to use teasels for raising the nap, claiming that the result is better; in particular, if a teasel meets serious resistance in the fabric, it will break, whereas a metal tool will rip the cloth. | https://en.wikipedia.org/wiki?curid=468291 | 609,822 |
2,069,182 | Whether pleomorphism-anaplasia warrants a worse prognosis has not been fully assessed so far. Chatten argued that increasing anaplasia in stage IV in comparison with stage III found in her cases suggested a trend toward higher stage (and worse prognosis) with anaplasia. However, within-stage differences were not significant, although cases without anaplasia fared better in each stage than those with. Abramowsky's et al. series of 7 children with anaplastic large cell neuroblastoma showed a better survival than previously reported cases. Joshi, et al. did not find any meaningful difference in clinical outcome between cases with or without anaplasia. Dehner pointed out the importance of recognizing this variant for differential diagnostic purposes. Expressions of pleomorphism-anaplasia have been fully acknowledged among the multifarious features of neuroblastoma in the classification by the International Neuroblastoma Pathology Committee. Recently Tornòczky et al. described 7 cases of large cell neuroblastoma characterized by larger nuclei with thick nuclear membranes and prominent nucleoli suggesting they might represent a distinct phenotype of neuroblastoma with aggressive clinical behavior. | https://en.wikipedia.org/wiki?curid=33437594 | 2,067,991 |
936,245 | Fernández and Frenking reported that the methyl, hydroxyl, and amino substituents resulted in a decrease in ΔE from the parent 2-propenal. Conversely, halide substituents of increasing atomic mass resulted in increasing ΔE. Because both the enone study and Hammett analysis study substituent effects (although in different species), Fernández and Frenking felt that comparing the two to investigate possible trends might yield significant insight into their own results. They observed a linear relationship between the ΔE values for the substituted enones and the corresponding Hammett constants. The slope of the graph was found to be -51.67, with a correlation coefficient of -0.97 and a standard deviation of 0.54. Fernández and Frenking conclude from this data that ..."the electronic effects of the substituents R on pi conjugation in homo- and heteroconjugated systems is similar and thus appears to be rather independent of the nature of the conjugating system.". | https://en.wikipedia.org/wiki?curid=2729378 | 935,750 |
2,032,550 | While each chemical problem presents its own unique challenges and opportunities, the design of a system for a specific analysis is complex and requires the assembly of several pieces of a spectroscopic puzzle. The data necessary for a successful design are spectral characteristics of light sources, detectors and a variety of optics to be used in the final assemblage, dispersion characteristics of the materials used in the wavelength range of interest, and a set of calibrated sample spectra for pattern-recognition-based analysis. With these pieces assembled, suitable application specific multivariate optical computer designs can be generated and the performance accurately modeled and predicted. | https://en.wikipedia.org/wiki?curid=8514693 | 2,031,380 |
2,206,905 | Biodesulfurization is an attractive alternative to sulfur removal, particularly in the crude oil fractions where there is an abundance of sulfur heterocycles. To date, pilot attempts for industrial applications have resorted to the use of whole bacterial systems, because biodesulfurization involves a sequential cascade of reactions by different enzymes and a large amount of cofactors participating in redox reactions either with the sulfur atom or molecular oxygen. However, they lacked the scalability desired for an industrial setup due to overall low enzyme efficiency, product feedback inhibition mechanisms and toxicity, or inadequate conditions for long-term bacterial growth. While cell-free recombinant enzymes would be desirable, known implementations are still well below the efficiency met for whole-cell ones. | https://en.wikipedia.org/wiki?curid=72414976 | 2,205,647 |
1,957,832 | Zhu "et al." experimented with the use of a 21.6 GHz probe to scan the fusion butt welds of HDPE pipe. They compared a reference scan of a good weld with scans of welds with lack of fusion and cold welds. These types of weld defects can be difficult to detect since they don't necessarily result in laminations that would strongly reflect a signal. The defective welds were made by adding various delay times between the end of heating and start of fusion as well as welding with low temperature and pressure. In the scan images, the good weld appeared as a uniform line. The defective welds exhibited various discontinuities and a non-uniform appearance. Mechanical testing of the welds showed a marked decrease in properties, with reductions in the yield stress of one-third to one-half the value of the good weld. Their research did not include the development of quantitative acceptance criteria which would be needed for use in production applications. | https://en.wikipedia.org/wiki?curid=60061507 | 1,956,708 |
368,526 | Further advances in the understanding of AML occurred rapidly with the development of new technology. In 1877, Paul Ehrlich developed a technique of staining blood films which allowed him to describe in detail normal and abnormal white blood cells. Wilhelm Ebstein introduced the term "acute leukemia" in 1889 to differentiate rapidly progressive and fatal leukemias from the more indolent chronic leukemias. The term "myeloid" was coined by Franz Ernst Christian Neumann in 1869, as he was the first to recognize white blood cells were made in the bone marrow (Greek: , "", ) as opposed to the spleen. The technique of bone marrow examination to diagnose leukemia was first described in 1879 by Mosler. Finally, in 1900, the myeloblast, which is the malignant cell in AML, was characterized by Otto Naegeli, who divided the leukemias into myeloid and lymphocytic. | https://en.wikipedia.org/wiki?curid=4323952 | 368,333 |
413,208 | Vaughan was born September 20, 1910, in Kansas City, Missouri, as Dorothy Jean Johnson. She was the daughter of Annie and Leonard Johnson. At the age of seven, her family moved to Morgantown, West Virginia, where she graduated from Beechurst High School in 1925 as her class valedictorian. Vaughan received a full-tuition scholarship from West Virginia Conference of the A.M.E. Sunday School Convention to attend Wilberforce University in Wilberforce, Ohio. She joined the Alpha Kappa Alpha chapter at Wilberforce and graduated in 1929 with a B.A. in mathematics. In 1932, she married Howard Vaughan, who died in 1955. The couple moved to Newport News, Virginia, where they had six children: Ann, Maida, Leonard, Kenneth, Michael and Donald. The family also lived with Howard's wealthy and respected parents and grandparents on South Main Street in Newport News, Virginia. Vaughan was very devoted to family and the church, which would play a huge factor in whether she would move to Hampton, Virginia, to work for NASA. | https://en.wikipedia.org/wiki?curid=48583314 | 413,006 |
1,933,695 | Parallelism is the concept of performing multiple tasks simultaneously, effectively reducing the time needed to perform a given task. The Tera-Scale research program is focused on the concept of utilizing many more cores than conventional to increase performance with parallelism. Based on their previous experience with increased core counts on CPUs, doubling the number of cores was able to nearly double the performance with no increase in power. With a greater amount of cores, there are possibilities of improved energy efficiency, improved performance, extended lifetimes and new capabilities. Tera-Scale processors would improve energy efficiency by being able to "put to sleep" cores that are unneeded at the time while being able to improve performance by intelligently redistributing workloads to ensure an even workload spread across the chip. Extended lifetimes are also capable by tera-scale processors due to the possibility of having reserve cores that could be brought online when a core fails in the processor. Lastly, the processors would gain new capabilities and functionality as dedicated hardware engines, such as graphics engines, could be integrated. | https://en.wikipedia.org/wiki?curid=11997021 | 1,932,587 |
1,206,752 | Pteropods are found in all major oceans, usually below the ocean surface and in all levels of latitude. Pteropods can be found lower than 10 meters, but in less amounts in terms of biomass, however, pteropod distribution is more spread out deeper based on findings. This can be explained as Pteropods from tropical areas become more common in deeper areas. They are not found commonly in the deep sea, in fact, few live lower than 500 meters below sea level. Continental shelves, areas containing many opportunities for nutrients, and productivity are locations in which Pteropods are usually populous, according to patterns in data. Springtime is a peak season for pteropoda, as they reach higher populations, though data shows that pteropoda south of the equator are less abundant seasonally. In addition, current data suggests that 93% of the world's pteropods are part of the Thecosomata family, while the 7% are Gymnosomata. | https://en.wikipedia.org/wiki?curid=1772263 | 1,206,107 |
1,017,983 | The Berkeley team had been worried that another group might discover lighter isotopes of element 100 through ion-bombardment techniques before they could publish their classified research, and this proved to be the case. A group at the Nobel Institute for Physics in Stockholm independently discovered the element, producing an isotope later confirmed to be Fm ("t" = 30 minutes) by bombarding a target with oxygen-16 ions, and published their work in May 1954. Nevertheless, the priority of the Berkeley team was generally recognized, and with it the prerogative to name the new element in honour of Enrico Fermi, the developer of the first artificial self-sustained nuclear reactor. Fermi was still alive when the name was proposed, but had died by the time it became official. | https://en.wikipedia.org/wiki?curid=10822 | 1,017,459 |
1,433,307 | Wapusk National Park shares its southwestern border with the Churchill Wildlife Management Area (WMA) which was established in 1978. Wapusk National Park itself was established to protect the area which is a unique transitional zone between three biomes and the existing strong biodiversity among plant and animal species. These three biomes include tundra, marine, and boreal. Wapusk National Park was created with future generations in mind, so they can enjoy the park and all its diversity. To ensure this goal is met the Ecological Integrity Monitoring Program (EIMP) builds baseline data to monitor climate change impacts, and the restoration of ecosystems. They work with a variety of external organizations including researchers, provincial governments, and indigenous communities to monitor human and natural change to strengthen resiliency and persistence within ecosystems. | https://en.wikipedia.org/wiki?curid=2023242 | 1,432,503 |
1,627,292 | The manuscript for "Man and His Gods" (1952), which Smith describes as "a simple story of man's changing ideas about himself and his place in nature," was declined by several publishers and reduced from about 275,000 to 250,000 words before it was accepted by Little, Brown and Company. The publisher made further cuts for length, which Smith approved of. It considers "man's ideas about the supernatural in the perspective of the evolution of western theology and philosophy from the ancient Egyptians to the nineteenth century", culminating in Darwin's theory of evolution and the reaction to it, including the thoughts of Thomas Henry Huxley and the relationship of modern thought to that of pre-evolutionist philosophers John Locke, David Hume and Immanuel Kant. Albert Einstein says in the foreword: | https://en.wikipedia.org/wiki?curid=1556000 | 1,626,374 |
1,975,860 | The first cosmic ray experiment was started in 1955 by B. V. Sreekantan by setting up cloud chambers that heralded the beginning of research at the Cosmic Ray Laboratory (CRL) in Ooty. The next decade witnessed a variety of experiments involving high energy interactions and extensive air shower studies in this laboratory. The world's largest multiplate cloud chamber was operated here as part of an air shower array and significant results on the high energy nuclear interactions and cores of extensive air showers were obtained. A triple set-up comprising an air Cherenkov counter, a multiplate cloud chamber and a total absorption spectrometer was operated in the early seventies to study the differences in the characteristics of interactions with nuclei of protons and pions in the energy range 10-40 GeV. This enabled the time structure study of nuclear active components of air showers and led to the discovery that the nucleon-anti-nucleon production cross-section considerably increases with energy. | https://en.wikipedia.org/wiki?curid=7206612 | 1,974,723 |
355,649 | Non-academic affiliations include: H. G. Wells, author; Nikolas Tombazis, chief car designer at McLaren and Ferrari; Ralph Robins, CEO of Rolls-Royce; Brian May, guitarist of rock band Queen; Chew Choon Seng, CEO of Singapore Airlines; Sir Julius Vogel, former Prime Minister of New Zealand; Rajiv Gandhi, former Prime Minister of India; Teo Chee Hean, Senior Minister of Singapore (formerly Deputy Prime Minister of Singapore); Edem Tengue, Minister of maritime economy of the republic of Togo; Huw Thomas, Physician to the Queen; Sir Roger Bannister, ran the first four-minute mile; David Warren, inventor of the flight data recorder and cockpit voice recorder; Andreas Mogensen, first Danish astronaut; Winston Wong, entrepreneur; Alan Howard, hedge fund manager and philanthropist; Cyrus Pallonji Mistry, former chairman of the Tata Group; Michael Birch, entrepreneur; Henry Charles Stephens, politician; Sir Michael Uren, businessman and philanthropist; Ian Read, CEO of Pfizer, Pallab Ghosh, BBC correspondent, Hannah Devlin, science journalist; , member of House of Representatives of the Republic of Indonesia. | https://en.wikipedia.org/wiki?curid=61116 | 355,466 |
232,620 | By the 1970s, NICUs were an established part of hospitals in the developed world. In Britain, some early units ran community programmes, sending experienced nurses to help care for premature babies at home. But increasingly technological monitoring and therapy meant special care for babies became hospital-based. By the 1980s, over 90% of births took place in hospital. The emergency dash from home to the NICU with baby in a transport incubator had become a thing of the past, though transport incubators were still needed. Specialist equipment and expertise were not available at every hospital, and strong arguments were made for large, centralised NICUs. On the downside was the long travelling time for frail babies and for parents. A 1979 study showed that 20% of babies in NICUs for up to a week were never visited by either parent. Centralised or not, by the 1980s few questioned the role of NICUs in saving babies. Around 80% of babies born weighing less than 1.5 kg now survived, compared to around 40% in the 1960s. From 1982, pediatricians in Britain could train and qualify in the sub-specialty of neonatal medicine. | https://en.wikipedia.org/wiki?curid=1466758 | 232,501 |
164,391 | San Lorenzo Colossal Head 5 is also known as San Lorenzo Monument 5. The monument stands high and measures wide by deep. It weighs 11.6 tons. The head was discovered by Matthew Stirling in 1946, face down in a gully to the south of the principal mound. The head is particularly well executed and is likely to have been found close to its original location. Ceramics recovered during its excavation became mixed with those from the excavation of Head 4. The mixed ceramics have been dated to the San Lorenzo and Villa Alta phases (approximately 1400–1000 BC and 800–1000 AD respectively). Colossal Head 5 is particularly well preserved, although the back of the headdress band was damaged when the head was moved from the archaeological site. The band of the headdress is set at an angle and has a notch above the bridge of the nose. The headdress is decorated with jaguar paws; this general identification of the decoration is contested by Beatriz de la Fuente since the "paws" have three claws each; she identifies them as the claws of a bird of prey. At the back of the head, ten interlaced strips form a net decorated with disc motifs. Two short straps descend from the headdress in front of the ears. The ears are adorned with disc-shaped earspools with pegs. The face is that of an ageing man with wrinkles under the eyes and across the bridge of the nose, and a forehead that is creased in a frown. The lips are slightly parted. Colossal Head 5 has been moved to the Museo de Antropología de Xalapa. | https://en.wikipedia.org/wiki?curid=35721801 | 164,306 |
14,596 | From 1952 to 1977, zoologist Sidnie Manton and others argued that arthropods are polyphyletic, in other words, that they do not share a common ancestor that was itself an arthropod. Instead, they proposed that three separate groups of "arthropods" evolved separately from common worm-like ancestors: the chelicerates, including spiders and scorpions; the crustaceans; and the uniramia, consisting of onychophorans, myriapods and hexapods. These arguments usually bypassed trilobites, as the evolutionary relationships of this class were unclear. Proponents of polyphyly argued the following: that the similarities between these groups are the results of convergent evolution, as natural consequences of having rigid, segmented exoskeletons; that the three groups use different chemical means of hardening the cuticle; that there were significant differences in the construction of their compound eyes; that it is hard to see how such different configurations of segments and appendages in the head could have evolved from the same ancestor; and that crustaceans have biramous limbs with separate gill and leg branches, while the other two groups have uniramous limbs in which the single branch serves as a leg. | https://en.wikipedia.org/wiki?curid=19827221 | 14,591 |
1,765,166 | Bioseparations on a production scale are enhanced by monolith column technologies as well. The fast separations and high resolving power of monoliths for large molecules means that real-time analysis on production fermentors is possible. Fermentation is well known for its use in making alcoholic beverages, but is also an essential step in the production of vaccines for rabies and other viruses. Real-time, on-line analysis is critical for monitoring of production conditions, and adjustments can be made if necessary. Boehringer Ingelheim Austria has validated a method with cGMP (commercial good manufacturing practices) for production of pharmaceutical-grade DNA plasmids. They are able to process 200L of fermentation broth on an 800mL monolith. At BIA Separations, processing time of the tomato mosaic virus decreased considerably from the standard five days of manually intensive work to equivalent purity and better recovery in only two hours with a monolith column. Other viruses have been purified on monoliths as well. | https://en.wikipedia.org/wiki?curid=22131699 | 1,764,173 |
1,447,810 | Assume for simplicity that we are considering a single binary character (it can either be + or -) distributed on the unrooted "true tree" with branch lengths proportional to amount of character state change, shown in the figure. Because the evolutionary distance from B to D is small, we assume that in the vast majority of all cases, B and D will exhibit the same character state. Here, we will assume that they are both + (+ and - are assigned arbitrarily and swapping them is only a matter of definition). If this is the case, there are four remaining possibilities. A and C can both be +, in which case all taxa are the same and all the trees have the same length. A can be + and C can be -, in which case only one character is different, and we cannot learn anything, as all trees have the same length. Similarly, A can be - and C can be +. The only remaining possibility is that A and C are both -. In this case, however, we view either A and C, or B and D, as a group with respect to the other (one character state is ancestral, the other is derived, and the ancestral state does not define a group). As a consequence, when we have a "true tree" of this type, the more data we collect (i.e. the more characters we study), the more of them are homoplastic and support the wrong tree. Of course, when dealing with empirical data in phylogenetic studies of actual organisms, we never know the topology of the true tree, and the more parsimonious (AC) or (BD) might well be the correct hypothesis. | https://en.wikipedia.org/wiki?curid=2388260 | 1,446,994 |
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