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167,603 | 1958 was a watershed in another crucial way for Formula One. Against a small field of Ferraris and Maseratis, Stirling Moss won the Argentine Grand Prix driving a mid-engined Cooper entered by the private team of Rob Walker, and powered by a 2-litre Coventry-Climax Straight-4. This was the first victory for a car with the engine mounted behind the driver in Formula One. It was also the first World Championship GP win for a private entrant (excepting the Indianapolis 500 where all the entries were technically private entrants using bought-in chassis). The next Grand Prix in Monaco was also won by the same Cooper car, this time driven by Maurice Trintignant and facing more substantial opposition. Powered by undersized engines, the Coopers remained outsiders in 1958 but as soon as the new 2.5-litre Coventry-Climax engine was available, the little British cars went on to dominate Formula One. The 1959 season was effectively the start of the mid-engined revolution, and this season saw fierce competition between the works Cooper of Australian Jack Brabham and Moss in the Walker team's Cooper. The Getrag-modified Citroën Traction Avant transaxle proved to be the Achilles heel of the Coopers, so Walker switched to a transaxle manufactured by ex-Maserati engineer Valerio Colotti. The special transmission turned out to be more unreliable than the standard part, and Brabham took the title with Moss second. | https://en.wikipedia.org/wiki?curid=640098 | 167,516 |
1,423,704 | Jupiter's intense radiation belts near the orbit of Io forced "Galileo" to come no closer than the orbit of Europa until the end of the first extended mission in 1999. Despite the lack of close-up imaging and mechanical problems that greatly restricted the amount of data returned, several significant discoveries at Io were made during "Galileo"<nowiki>'</nowiki>s two-year, primary mission. During the first several orbits, "Galileo" mapped Io in search of surface changes that occurred since the Voyager encounters 17 years earlier. This included the appearance of a new lava flow, Zamama, and the shifting of the Prometheus plume by to the west, tracking the end of a new lava flow at Prometheus. Starting with "Galileo"<nowiki>'</nowiki>s first orbit, the spacecraft's camera, the Solid-State Imager (SSI), began taking one or two images per orbit of Io while the moon was in Jupiter's shadow. This allowed "Galileo" to monitor high-temperature volcanic activity on Io by observing thermal emission sources across its surface. The same eclipse images also allowed "Galileo" scientists to observe aurorae created by the interaction between Io's atmosphere and volcanic plumes with the Io flux tube and the plasma torus. During "Galileo"<nowiki>'</nowiki>s ninth orbit, the spacecraft observed a major eruption at Pillan Patera, detecting high-temperature thermal emission and a new volcanic plume. The temperatures observed at Pillan and other volcanoes confirmed that volcanic eruptions on Io consist of silicate lavas with magnesium-rich mafic and ultramafic compositions, with volatiles like sulfur and sulfur dioxide serving a similar role to water and carbon dioxide on Earth. During the following orbit, "Galileo" found that Pillan was surrounded by a new, dark pyroclastic deposit composed of silicate minerals such as orthopyroxene. The Near-Infrared Mapping Spectrometer (NIMS) observed Io on a number occasions during the primary mission, mapping its volcanic thermal emission and the distribution of sulfur dioxide frost, the absorption bands of which dominate Io's near-infrared spectrum. | https://en.wikipedia.org/wiki?curid=26237277 | 1,422,903 |
1,851,583 | The Department of Biomaterials, headed by Peter Fratzl, focuses on interdisciplinary research in the field of biological and biomimetic materials. The emphasis is on understanding how the mechanical or other physical properties are governed by structure and composition and how they adopt to environmental conditions. Furthermore, research on natural materials (such as bone or wood) has potential applications in many fields. First, design concepts for new materials may be improved by learning from Nature. Second, the understanding of basic mechanisms by which the structure of bone or connective tissue is optimized opens the way for studying diseases and, thus, for contributing to diagnosis and development of treatment strategies. A third option is to use structures grown by Nature and transform them by physical or chemical treatment into technically relevant materials (biotemplating). Given the complexity of natural materials, new approaches for structural characterization are needed. Some of these are further developed in the Department, in particular for studying hierarchical structures. | https://en.wikipedia.org/wiki?curid=6866309 | 1,850,522 |
1,315,984 | STSE education draws on holistic ways of knowing, learning, and interacting with science. A recent movement in science education has bridged science and technology education with society and environment awareness through critical explorations of place. The project Science and the City, for example, took place during the school years 2006-2007 and 2007-2008 involving an intergenerational group of researchers: 36 elementary students (grades 6, 7 & 8) working with their teachers, 6 university-based researchers, parents and community members. The goal was to come together, learn science and technology together, and use this knowledge to provide meaningful experiences that make a difference to the lives of friends, families, communities and environments that surround the school. The collective experience allowed students, teachers and learners to foster imagination, responsibility, collaboration, learning and action. The project has led to a series of publications: | https://en.wikipedia.org/wiki?curid=7895944 | 1,315,259 |
182,233 | As expected from periodic trends, lanthanum has the largest atomic radius of the lanthanides. Hence, it is the most reactive among them, tarnishing quite rapidly in air, turning completely dark after several hours and can readily burn to form lanthanum(III) oxide, LaO, which is almost as basic as calcium oxide. A centimeter-sized sample of lanthanum will corrode completely in a year as its oxide spalls off like iron rust, instead of forming a protective oxide coating like aluminium, scandium, yttrium, and lutetium. Lanthanum reacts with the halogens at room temperature to form the trihalides, and upon warming will form binary compounds with the nonmetals nitrogen, carbon, sulfur, phosphorus, boron, selenium, silicon and arsenic. Lanthanum reacts slowly with water to form lanthanum(III) hydroxide, La(OH). In dilute sulfuric acid, lanthanum readily forms the aquated tripositive ion : this is colorless in aqueous solution since La has no d or f electrons. Lanthanum is the strongest and hardest base among the rare earth elements, which is again expected from its being the largest of them. | https://en.wikipedia.org/wiki?curid=17744 | 182,137 |
2,153,448 | Since then, the chair has been occupied by a number of noted experimental physicists. For example, George Francis FitzGerald (1881) is known for his work in electromagnetic theory and for the Lorentz–FitzGerald contraction, which became an integral part of Albert Einstein's special theory of relativity. Ernest Walton (1946) is the only Irish scientist to win the Nobel Prize for Physics. He is best known for his work with John Cockcroft to construct one of the earliest types of particle accelerator, complete with its Cockcroft-Walton voltage-multiplying circuit, devised by themselves and subsequently reproduced widely in high-voltage generators elsewhere. In experiments performed at Cambridge University in the early 1930s using the generator, Walton and Cockcroft became the first team to use a particle beam to transform one element to another. | https://en.wikipedia.org/wiki?curid=51633206 | 2,152,217 |
156,715 | Optical magnetometry makes use of various optical techniques to measure magnetization. One such technique, Kerr magnetometry makes use of the magneto-optic Kerr effect, or MOKE. In this technique, incident light is directed at the sample's surface. Light interacts with a magnetized surface nonlinearly so the reflected light has an elliptical polarization, which is then measured by a detector. Another method of optical magnetometry is Faraday rotation magnetometry. Faraday rotation magnetometry utilizes nonlinear magneto-optical rotation to measure a sample's magnetization. In this method a Faraday modulating thin film is applied to the sample to be measured and a series of images are taken with a camera that senses the polarization of the reflected light. To reduce noise, multiple pictures are then averaged together. One advantage to this method is that it allows mapping of the magnetic characteristics over the surface of a sample. This can be especially useful when studying such things as the Meissner effect on superconductors. Microfabricated optically pumped magnetometers (µOPMs) can be used to detect the origin of brain seizures more precisely and generate less heat than currently available superconducting quantum interference devices, better known as SQUIDs. The device works by using polarized light to control the spin of rubidium atoms which can be used to measure and monitor the magnetic field. | https://en.wikipedia.org/wiki?curid=83060 | 156,643 |
125,940 | Endotracheal intubation and mechanical ventilation may be used to ensure proper oxygen supply and provide a secure airway. Hypotension (low blood pressure), which has a devastating outcome in TBI, can be prevented by giving intravenous fluids to maintain a normal blood pressure. Failing to maintain blood pressure can result in inadequate blood flow to the brain. Blood pressure may be kept at an artificially high level under controlled conditions by infusion of norepinephrine or similar drugs; this helps maintain cerebral perfusion. Body temperature is carefully regulated because increased temperature raises the brain's metabolic needs, potentially depriving it of nutrients. Seizures are common. While they can be treated with benzodiazepines, these drugs are used carefully because they can depress breathing and lower blood pressure. Anti-convulsant medications have only been found to be useful for reducing the risk of an early seizure. Phenytoin and leviteracetam appear to have similar levels of effectiveness for preventing early seizures. People with TBI are more susceptible to side effects and may react adversely to some medications. During treatment monitoring continues for signs of deterioration such as a decreasing level of consciousness. | https://en.wikipedia.org/wiki?curid=1057414 | 125,888 |
873,245 | A deep sea mining venture in Papua New Guinea, the Solwara 1 Project, was granted a mining permit to begin mining a high grade copper-gold resource from a weakly active hydrothermal vent. This controversial project generated an enormous backlash from the community and environmental activists The Solwara 1 Project was located at 1600 metres water depth in the Bismarck Sea, New Ireland Province. Using ROV (remotely operated underwater vehicles) technology developed by UK-based Soil Machine Dynamics, Nautilus Minerals Inc. was the first company of its kind to announce plans to begin full-scale undersea excavation of mineral deposits. However a dispute with the government of Papua-New Guinea delayed production and operations until early 2018. In September 2019, it was announced that the project had collapsed as Nautilus Minerals Inc. went into administration and its major creditors sought to recoup the millions of dollars they had sunk into the project. The Prime Minister of Papua New Guinea called the project a "total failure", sparking calls for a deep sea mining moratorium from his Pacific counterparts. | https://en.wikipedia.org/wiki?curid=10431114 | 872,785 |
1,958,810 | In some global optimization problems the analytical definition of the objective function is unknown and it is only possible to get values at fixed points. There are objective functions in which the cost of an evaluation is very high, for example when the evaluation is the result of an experiment or a particularly onerous measurement. In these cases, the search of the global extremum (maximum or minimum) can be carried out using a methodology named "Bayesian optimization", which tend to obtain a priori the best possible result with a predetermined number of evaluations. In summary it is assumed that outside the points in which it has already been evaluated, the objective function has a pattern which can be represented by a stochastic process with appropriate characteristics. The stochastic process is taken as a model of the objective function, assuming that the probability distribution of its extrema gives the best indication about extrema of the objective function. In the simplest case of the one-dimensional optimization, given that the objective function has been evaluated in a number of points, there is the problem to choose in which of the intervals thus identified is more appropriate to invest in a further evaluation. If a Wiener stochastic process is chosen as a model for the objective function, it is possible to calculate the probability distribution of the model extreme points inside each interval, conditioned by the known values at the interval boundaries. The comparison of the obtained distributions provides a criterion for selecting the interval in which the process should be iterated. The probability value of having identified the interval in which falls the global extremum point of the objective function can be used as a stopping criterion. Bayesian optimization is not an efficient method for the accurate search of local extrema so, once the search range has been restricted, depending on the characteristics of the problem, a specific local optimization method can be used. | https://en.wikipedia.org/wiki?curid=52629507 | 1,957,683 |
167,645 | In 1989, turbos were banned and new regulations allowing only naturally aspirated engines up to 3.5 litres were put in their place. The dominance of McLaren-Honda continued for the next 3 seasons, Prost winning the title in 1989, Senna in and . The V10 and V12 engines produced by the Japanese manufacturer proved to be just as good as the turbo V6s before them, and the V10 was the best engine over the two seasons it was used and developed by Honda. The championship was marred however by the fierce rivalry between the two men, culminating in a pair of clashes at the Japanese Grands Prix of 1989 and 1990. They both dominated Formula One from 1988 to 1990, winning 37 of the 48 Grand Prix staged and each scoring almost twice as many points as the third-place driver in those championships. In 1989 Prost 'closed the door' on his overtaking teammate while Senna later freely admitted to deliberately driving into Prost in the 1990 race, drawing stiff condemnation from all quarters of Formula One. Senna, however, was more concerned with the threat (and opportunity) afforded by the resurgent Williams, now powered by Renault (the French giant's innovative engine technology resulted in major progress) and designed by aerodynamics genius Adrian Newey which were to dominate Formula One for the next 7 years. | https://en.wikipedia.org/wiki?curid=640098 | 167,558 |
205,212 | The Lunar Prospector probe, launched in 1998, employed a neutron spectrometer to measure the amount of hydrogen in the lunar regolith near the polar regions. It was able to determine hydrogen abundance and location to within 50 parts per million and detected enhanced hydrogen concentrations at the lunar north and south poles. These were interpreted as indicating significant amounts of water ice trapped in permanently shadowed craters, but could also be due to the presence of the hydroxyl radical (OH) chemically bound to minerals. Based on data from Clementine and Lunar Prospector, NASA scientists have estimated that, if surface water ice is present, the total quantity could be of the order of . In July 1999, at the end of its mission, the Lunar Prospector probe was deliberately crashed into Shoemaker crater, near the Moon's south pole, in the hope that detectable quantities of water would be liberated. However, spectroscopic observations from ground-based telescopes did not reveal the spectral signature of water. | https://en.wikipedia.org/wiki?curid=1580280 | 205,106 |
223,418 | Each device in a MANET is free to move independently in any direction, and will therefore change its links to other devices frequently. Each must forward traffic unrelated to its own use, and therefore be a router. The primary challenge in building a MANET is equipping each device to continuously maintain the information required to properly route traffic. This becomes harder as the scale of the MANET increases due to 1) the desire to route packets to/through every other node, 2) the percentage of overhead traffic needed to maintain real-time routing status, 3) each node has its own goodput to route independent and unaware of others needs, and 4) all must share limited communication bandwidth, such as a slice of radio spectrum. Such networks may operate by themselves or may be connected to the larger Internet. They may contain one or multiple and different transceivers between nodes. This results in a highly dynamic, autonomous topology. MANETs usually have a routable networking environment on top of a link layer ad hoc network. | https://en.wikipedia.org/wiki?curid=6624928 | 223,304 |
1,517,960 | Streaming instabilities, first described by Andrew Youdin and Jeremy Goodman, are driven by differences in the motions of the gas and solid particles in the protoplanetary disk. The gas is hotter and denser closer to the star, creating a pressure gradient that partially offsets gravity from the star. The partial support of the pressure gradient allows the gas to orbit at roughly 50 m/s below the Keplerian velocity at its distance. The solid particles, however, are not supported by the pressure gradient and would orbit at Keplerian velocities in the absence of the gas. The difference in velocities results in a headwind that causes the solid particles to spiral toward the central star as they lose momentum to aerodynamic drag. The drag also produces a back reaction on the gas, increasing its velocity. When solid particles cluster in the gas, the reaction reduces the headwind locally, allowing the cluster to orbit faster and undergo less inward drift. The slower drifting clusters are overtaken and joined by isolated particles, increasing the local density and further reducing radial drift, fueling an exponential growth of the initial clusters. In simulations the clusters form massive filaments that can grow or dissipate, and that can collide and merge or split into multiple filaments. The separation of filaments averages 0.2 gas scale heights, roughly 0.02 AU at the distance of the asteroid belt. The densities of the filaments can exceed a thousand times the gas density, sufficient to trigger the gravitational collapse and fragmentation of the filaments into bound clusters. | https://en.wikipedia.org/wiki?curid=48840652 | 1,517,103 |
1,442,244 | A traditional sequence early in the 20th century would leave topics such as algebra or geometry entirely for high school, and statistics until college, but newer standards introduce the basic principles needed for understanding these topics very early. For example, most American standards now require children to learn to recognize and extend patterns in kindergarten. This very basic form of algebraic reasoning is extended in elementary school to recognize patterns in functions and arithmetic operations, such as the distributive law, a key principle for doing high school algebra. Most curricula today encourage children to reason about geometric shapes and their properties in primary school as preparation for more advanced reasoning in a high school geometry course. Current standards require children to learn basic statistical ideas such as organizing data with bar charts. More sophisticated concepts such as algebraic expressions with numbers and letters, geometric surface area and statistical means and medians occur in sixth grade in the newest standards. | https://en.wikipedia.org/wiki?curid=6877259 | 1,441,431 |
1,384,054 | Different carrageenan types differ in composition and conformation, resulting in a wide range of rheological and functional properties. Carrageenans are used in a variety of commercial applications as gelling, thickening, and stabilizing agents, especially in food products such as frozen desserts, chocolate milk, cottage cheese, whipped cream, instant products, yogurt, jellies, pet foods, and sauces. Aside from these functions, carrageenans are used in pharmaceutical formulations, cosmetics, and industrial applications such as mining. Carrageenan is extracted from this seaweed in two ways. In native extraction, the seaweed is made into an aqueous solution, and the residue is filtered, leaving nearly pure carrageenan. The alkaline-modified method is less expensive and easier. The seaweed is mixed in an alkali solution, leaving a mixture of carrageenan and cellulose that can be sold as semirefined carrageenan. "K. alvarezii" is affected by ice-ice, a disease that severely reduces its yield. | https://en.wikipedia.org/wiki?curid=16721343 | 1,383,287 |
373,138 | Monsoons are caused by the different amplitudes of surface temperature seasonal cycles between land and oceans. This differential warming occurs because heating rates differ between land and water. Ocean heating is distributed vertically through a "mixed layer" that may be 50 meters deep through the action of wind and buoyancy-generated turbulence, whereas the land surface conducts heat slowly, with the seasonal signal penetrating only a meter or so. Additionally, the specific heat capacity of liquid water is significantly greater than that of most materials that make up land. Together, these factors mean that the heat capacity of the layer participating in the seasonal cycle is much larger over the oceans than over land, with the consequence that the land warms and cools faster than the ocean. In turn, air over the land warms faster and reaches a higher temperature than does air over the ocean. The warmer air over land tends to rise, creating an area of low pressure. The pressure anomaly then causes a steady wind to blow toward the land, which brings the moist air over the ocean surface with it. Rainfall is then increased by the presence of the moist ocean air. The rainfall is stimulated by a variety of mechanisms, such as low-level air being lifted upwards by mountains, surface heating, convergence at the surface, divergence aloft, or from storm-produced outflows near the surface. When such lifting occurs, the air cools due to expansion in lower pressure, which in turn produces condensation and precipitation. | https://en.wikipedia.org/wiki?curid=523282 | 372,943 |
88,623 | Homeostasis does not govern every activity in the body. For instance the signal (be it via neurons or hormones) from the sensor to the effector is, of necessity, highly variable in order to convey information about the direction and magnitude of the error detected by the sensor. Similarly the effector's response needs to be highly adjustable to reverse the error – in fact it should be very nearly in proportion (but in the opposite direction) to the error that is threatening the internal environment. For instance, the arterial blood pressure in mammals is homeostatically controlled, and measured by stretch receptors in the walls of the aortic arch and carotid sinuses at beginnings of the internal carotid arteries. The sensors send messages via sensory nerves to the medulla oblongata of the brain indicating whether the blood pressure has fallen or risen, and by how much. The medulla oblongata then distributes messages along motor or efferent nerves belonging to the autonomic nervous system to a wide variety of effector organs, whose activity is consequently changed to reverse the error in the blood pressure. One of the effector organs is the heart whose rate is stimulated to rise (tachycardia) when the arterial blood pressure falls, or to slow down (bradycardia) when the pressure rises above set point. Thus the heart rate (for which there is no sensor in the body) is not homeostatically controlled, but is one of effector responses to errors in the arterial blood pressure. Another example is the rate of sweating. This is one of the effectors in the homeostatic control of body temperature, and therefore highly variable in rough proportion to the heat load that threatens to destabilize the body's core temperature, for which there is a sensor in the hypothalamus of the brain. | https://en.wikipedia.org/wiki?curid=13980 | 88,587 |
31,429 | Since glucose is a basic necessity of many organisms, a correct understanding of its chemical makeup and structure contributed greatly to a general advancement in organic chemistry. This understanding occurred largely as a result of the investigations of Emil Fischer, a German chemist who received the 1902 Nobel Prize in Chemistry for his findings. The synthesis of glucose established the structure of organic material and consequently formed the first definitive validation of Jacobus Henricus van 't Hoff's theories of chemical kinetics and the arrangements of chemical bonds in carbon-bearing molecules. Between 1891 and 1894, Fischer established the stereochemical configuration of all the known sugars and correctly predicted the possible isomers, applying Van 't Hoff's theory of asymmetrical carbon atoms. The names initially referred to the natural substances. Their enantiomers were given the same name with the introduction of systematic nomenclatures, taking into account absolute stereochemistry (e.g. Fischer nomenclature, / nomenclature). | https://en.wikipedia.org/wiki?curid=12950 | 31,419 |
1,702,350 | In the 1970s, complex modelling revolved around manually identifying features on the surfaces of the interactors, and interpreting the consequences for binding, function and activity; any computer programmes were typically used at the end of the modelling process, to discriminate between the relatively few configurations which remained after all the heuristic constraints had been imposed. The first use of computers was in a study on hemoglobin interaction in sickle-cell fibres. This was followed in 1978 by work on the trypsin-BPTI complex. Computers discriminated between good and bad models using a scoring function which rewarded large interface area, and pairs of molecules in contact but not occupying the same space. The computer used a simplified representation of the interacting proteins, with one interaction centre for each residue. Favorable electrostatic interactions, including hydrogen bonds, were identified by hand. | https://en.wikipedia.org/wiki?curid=2606518 | 1,701,395 |
173,362 | Sex pheromone production is likely a common feature of green algae, although only studied in detail in a few model organisms. "Volvox" is a genus of chlorophytes. Different species form spherical colonies of up to 50,000 cells. One well-studied species, "Volvox carteri" (2,000 – 6,000 cells) occupies temporary pools of water that tend to dry out in the heat of late summer. As their environment dries out, asexual "V. carteri" quickly die. However, they are able to escape death by switching, shortly before drying is complete, to the sexual phase of their life cycle that leads to production of dormant desiccation-resistant zygotes. Sexual development is initiated by a glycoprotein pheromone (Hallmann et al., 1998). This pheromone is one of the most potent known biological effector molecules. It can trigger sexual development at concentrations as low as 10M. Kirk and Kirk showed that sex-inducing pheromone production can be triggered experimentally in somatic cells by heat shock. Thus heat shock may be a condition that ordinarily triggers sex-inducing pheromone in nature. | https://en.wikipedia.org/wiki?curid=341046 | 173,271 |
1,227,030 | In a 2018 lecture in Boston Bill Gates called for a global effort to build a comprehensive pandemic preparedness and response system. During the COVID-19 pandemic he called upon world leaders to "take what has been learned from this tragedy and invest in systems to prevent future outbreaks". In a 2015 TED Talk he warned that "if anything kills over 10 million people in the next few decades, it's most likely to be a highly infectious virus rather than a war". Numerous prominent, authoritative, expert or otherwise influential figures have similarly warned about elevated, underprepared or contemporary risks of pandemics and the need for efforts on an "international scale" long before 2015 and since at least 1988. Later warnings include a 2015 study which concluded that "a potential risk of SARS-CoV re-emergence from viruses currently circulating in bat populations". | https://en.wikipedia.org/wiki?curid=63478457 | 1,226,369 |
457,950 | The string quintet was composed in the summer or early autumn of 1828, at the same time as Schubert composed his last three piano sonatas and several of the Schwanengesang songs. Schubert completed it in late September or early October, just two months before his death. Schubert submitted it to one of his publishers, Heinrich Albert Probst, for consideration, saying that "finally I have written a quintet for 2 violins, 1 viola, and 2 violoncelli ... the quintet rehearsal will only begin in the next few days. Should any of these compositions by any chance commend themselves to you, please let me know." Probst replied, asking only to see some of Schubert's vocal works and requesting more popular piano music. Even at this very late stage in Schubert's career, he was regarded as a composer who mainly focused on songs and piano pieces, and was definitely not taken seriously as a chamber music composer. The work remained unpublished at the time of Schubert's death in November 1828; the manuscript was sold to the Viennese publisher Diabelli by Schubert's brother Ferdinand shortly thereafter, but was neglected and indeed waited twenty-five years for its first publication in 1853. The manuscript and all sketches are now lost. The first known public performance occurred only three years earlier, on 17 November 1850 at the Musikverein in Vienna. | https://en.wikipedia.org/wiki?curid=2065505 | 457,727 |
2,118,295 | Sedimentary records are influenced by local topography and oceanic and atmospheric currents. Proxies of global climatic significance are, however, less ambiguous in paleotemperature interpretation. Marine biota have offered by far the most proxies for paleotemperature, of which the microfossils, because of their widespread, abundance and sensitive to latitudinal changes, have provided many primary important paleotemperature indicators. Identification of latitudinal indices species is usually the first attempt to tie their presence in sediments to paleotemperature fluctuations. Other properties of marine biota, including morphology, abundance, diversity, and geochemistry have also been successfully established as paleoclimate indicators. More complex statistical analyses (factor analysis, principal component, etc.) of biogeography have been able to link fauna assemblages to water masses for paleo-current reconstruction. List below are some key paleontological tools utilized by scientists to reconstruct paleotemperature history. | https://en.wikipedia.org/wiki?curid=69822725 | 2,117,077 |
1,804,130 | Tetrasome 15qter syndrome is an extremely rare congenital syndrome which is associated with mental retardation, overgrowth of the body or body part, skull bossing, short palpebral fissures, long philtrum, low-set ears, high-arched palate, retrognathia (i.e., abnormal posterior positioning of the maxilla or mandible), joint contractions, arachnodactyly, and/or, less commonly, kidney, genitourinary and various vascular and cardiac anomalies. The syndrome is caused by an sSMC bearing two copies (that are inverted duplications) of the genetic material on the q arm of chromosome 15 beginning at various sites between bands 23 and 26 and running to this arms terminus; this area is notated as (15) q24-qter. Individuals with this syndrome therefore have 4 copies of the genetic material that is in the sSMC, i.e. 2 from each normal chromosome and 2 from the sSMC. Centromeres are specialized DNA sequences of a chromosome that are required to link each sister chromatid of paired chromosomes and thereby to distribute each member of the paired chromosome to different daughter cells during mitosis and meiosis cell divisions. The sSMCs in tetraseome 15qter do not have a normal centromere; rather, they have a neocentromere, i.e. a new centromere that forms at a place on the chromosome that is usually not the site where the centromere of the copied chromosome (in this case chromosome 15) is located. Neocentromeric sSMCs of any type are associated with adverse outcomes in 90% of cases. The exact genetic material in this sSMC that contributes to the development of the cited birth defects has not been determined. | https://en.wikipedia.org/wiki?curid=2018913 | 1,803,116 |
1,362,957 | While HOTOL's proof-of-concept design study was being carried out, attempts were made by both industry and the British government to establish international cooperation to develop, produce, and deploy the spacecraft. In spite of American interest in the programme, there was little appetite amongst the members of the European Space Agency (ESA), and the British government was not prepared to depart from ESA cooperation. Additionally, technical issues were encountered, and there were allegations that comparisons with alternative launch systems such as conventional rocket vehicle using similar construction techniques failed to show much advantage to HOTOL. In 1989, funding for the project ended. The termination of development work on HOTOL led to the formation of Reaction Engines Limited (REL) to develop and produce Skylon, a proposed spacecraft based on HOTOL technologies, including its air-breathing engine. | https://en.wikipedia.org/wiki?curid=14301 | 1,362,204 |
288,452 | Polaris proved to be reliable, and its second-strike capability conferred greater strategic flexibility than any previous British nuclear weapons system. However it had a limited lifespan, and was expected to become obsolete by the 1990s. It was considered vital that an independent British deterrent could penetrate existing and future Soviet anti-ballistic missile (ABM) capabilities. An ABM system, the ABM-1 Galosh, defended Moscow, and NATO believed the USSR would continue to develop its effectiveness. The deterrent logic required the ability to threaten the destruction of the Soviet capital and other major cities. To ensure that a credible and independent nuclear deterrent was maintained, the UK developed an improved warhead package Chevaline, which replaced one of the three warheads in a Polaris missile with multiple decoys, chaff, and other defensive countermeasures. Chevaline was extremely expensive; it encountered many of the same issues that had affected the British nuclear weapons projects of the 1950s, and postponed, but did not avert, Polaris's obsolescence. | https://en.wikipedia.org/wiki?curid=9095461 | 288,295 |
682,165 | During January 2012, Direct Rail Services (DRS) announced that it had ordered a total of 15 new diesel locomotives from Vossloh España (now Stadler Rail). These locomotives, which entered service in the UK as , were part of the company's Eurolight family, redesigned to fit the smaller UK loading gauge. DRS had opted to procure a clean-sheet design after examining various existing alternatives, such as the ubiquitous British Rail Class 66 locomotive, which the company's management determined to be incapable of satisfactorily replacing its ageing fleet of s, largely due to inefficient engines and elevated operating costs. Stadler undertook development of the Class 68 over an 18 month period, during which the company studied several derivatives and modifications, including the use of alternative powerplants. Having presented such proposals to DRS, the latter became particularly interested in the electro-diesel arrangement, as the company's management recognised there was a potential role for a dual-mode locomotive in the UK market. | https://en.wikipedia.org/wiki?curid=14042699 | 681,809 |
1,453,250 | A more likely source of cellular plasticity is through the Regulation of gene expression, such that while two cells may have near identical DNA, the differential expression of certain genes results in variation. Research has shown that cells are capable of regulating gene expression at several stages: mRNA transcription, processing and transportation as well as in protein translation, post-translational processing and degradation. Regulatory proteins that bind to DNA, RNA, and/or proteins are key effectors in these processes and function by positively or negatively regulating specific protein level and function in a cell. And, while DNA binding transcription factors provide a mechanism for specific control of cellular responses, a model where DNA binding transcription factors are the sole regulators of gene activity is also unlikely. For example, in a study of Somatic-cell nuclear transfer, it was demonstrated that stable features of differentiation remain after the nucleus is transferred to a new cellular environment, suggesting that a stable and heritable mechanism of gene regulation was involved in the maintenance of the differentiated state in the absence of the DNA binding transcription factors. | https://en.wikipedia.org/wiki?curid=17704946 | 1,452,433 |
575,400 | In order for any export sales of the type to be successfully completed, PZL had to address two major obstacles. Firstly, the company was only capable of producing so many aircraft in the space of a year; PZL did not have the internal resources to substantially expand its production capacity, nor was financing from the Polish government or other bodies viewed as being particularly forthcoming during this time. According to Cynk, tentative customers for the fighter were typically adverse to making large currency exchanges as part of their payments, instead, they would usually prefer to pay in terms of goods (such as raw resources and industrial products) or to pay in numerous installments. Furthermore, Cynk claims that several deals which had been formed with PZL had fallen through or had been otherwise postponed due to difficulties encountered in agreeing acceptable terms of payment between the customer and the manufacturer. | https://en.wikipedia.org/wiki?curid=1139061 | 575,106 |
666,379 | In 2019, Nick Lane and colleagues show that vesicles form readily in seawater conditions at pH between 6.5 and >12 and temperatures 70 °C, meant to mimic the conditions of alkaline hydrothermal vents, with the presence of lipid mixtures, however a prebiotic source to such mixtures is unclear. Simple amphiphilic compounds in seawater do not assemble into vesicles because of the high concentration of ionic solutes. In hot spring conditions, self-assembly of vesicles occurs, which have a lower concentration of ionic solutes. Scientists oligomerized RNA in alkaline hydrothermal vent conditions in the laboratory. Although they were estimated to be 4 units in length, it implies RNA polymers possibly were synthesized at such environments. Experimental research at hot springs gave higher yields of RNA-like polymers than in the laboratory. The polymers were encapsulated in fatty acid vesicles when rehydrated, further supporting the hot spring hypothesis of abiogenesis. UV exposure have been shown to promote the synthesis of stable biomolecules like nucleotides. Research has shown that vesicles are binded and stabilized by prebiotic amino acids while in the presence of salt ions and magnesium ions, stabilization and binding increases by continuous wet-dry cycling. | https://en.wikipedia.org/wiki?curid=19179678 | 666,031 |
1,833,891 | Her algorithms address local and global continuous and integer optimization, stochastic optimal control, and uncertainty quantification problems. In her recent research algorithms, efficiency is improved with the use of surrogate response surfaces (usually with radial basis function (RBF)). The surrogates are iteratively built during the search process and with intelligent algorithms that effectively utilize computing distributed over parallel processors. The optimization and uncertainty quantification effort is used to improve model forecasts, to evaluate monitoring schemes and to have a tool for comparing alternative management practices. The objective functions can include partial differential equations or other computationally expensive models taking minutes or hours for each objective evaluation. Algorithms that are efficient because they require relatively few simulations are essential for doing calibration and uncertainty analysis on computationally expensive engineering simulation models. | https://en.wikipedia.org/wiki?curid=52572607 | 1,832,842 |
1,424,609 | TLR9 has been identified as a major player in systemic lupus erythematosus (SLE) and erythema nodosum leprosum (ENL). Loss of TLR9 exacerbates progression of SLE, and leads to increased activation of dendritic cells. TLR9 also controls the release of IgA and IFN-a in SLE, and loss of the receptor leads to higher levels of both molecules. In SLE, TLR9 and TLR7 have opposing effects. TLR9 regulates inflammatory response, while TLR7 promotes inflammatory response. TLR9 has an opposite effect in ENL. TLR9 is expressed at high levels on monocytes of ENL patients, and is positively linked to the secretion of proinflammatory cytokines TNF, IL-6, and IL-1β. TLR9 agonists and antagonists may be useful in treatment of a variety of inflammatory conditions, and research in this area is active. Autoimmune thyroid diseases have also been shown to correlate with an increase in expression of TLR9 on peripheral blood mononuclear cells (PBMCs). Patients with autoimmune thyroid diseases also have higher levels of the nuclear protein HMGB1 and RAGE protein, which together act as a ligand for TLR9. HMGB1 is released from lysed or damaged cells. HMGB1-DNA complex then binds to RAGE, and activates TLR9. TLR9 can work through MyD88, an adaptor molecule that increases the expression of NF-κB. However autoimmune thyroid diseases also increase sensitivity of MyD88 independent pathways. These pathways ultimately leads to the production of pro-inflammatory cytokines in PMBCs for patients with autoimmune thyroid diseases. Autoimmune diseases can also be triggered by activated cells undergoing apoptosis and being engulfed by antigen-presenting cells. Activation of cells leads to de-methylation, which exposes CpG regions of host DNA, allowing an inflammatory response to be activated through TLR9. Although it is possible that TLR9 also recognizes unmethylated DNA, TLR9 undoubtedly has a role in phagocytosis-induced autoimmunity. | https://en.wikipedia.org/wiki?curid=13977381 | 1,423,807 |
2,066,491 | Discrete Skeleton Evolution (DSE) describes an iterative approach to reducing a morphological or topological skeleton. It is a form of pruning in that it removes noisy or redundant branches (spurs) generated by the skeletonization process, while preserving information-rich "trunk" segments. The value assigned to individual branches varies from algorithm to algorithm, with the general goal being to convey the features of interest of the original contour with a few carefully chosen lines. Usually, clarity for human vision (aka. the ability to "read" some features of the original shape from the skeleton) is valued as well. DSE algorithms are distinguished by complex, recursive decision-making processes with high computational requirements. Pruning methods such as by structuring element (SE) convolution and the Hough transform are general purpose algorithms which quickly pass through an image and eliminate all branches shorter than a given threshold. DSE methods are most applicable when detail retention and contour reconstruction are valued. | https://en.wikipedia.org/wiki?curid=57225151 | 2,065,300 |
159,559 | Applications of prospect theory in the context of insurance seek to explain the consumer choices. Syndor (2010) suggests that the probability weighting aspect of prospect theory aims to explain the behaviour of the consumers who choose a higher premium for a reduced deductible even when the annualised claim rate is very low (approximately 5%). In a study of 50,000 customers, they had four options for the deductibles on their policy; $100, $250, $500, $1000. From this it was found that a $500 deductible resulted in a $715 annual premium and $1000 deductible being $615. The customers that chose the $500 deductible were paying an additional $100 per year even though the chance that a claim will be made is extremely low, and the deductible be paid. Under the expected utility framework, this can only be realised through high levels of risk aversion. Households place a greater weight on the probability that a claim will be made when choosing a policy, thus It is suggested that the reference point of the household significantly influences the decisions when it comes to premiums and deductibles. This is consistent with the theory that people assign excessive weight to scenarios with low probabilities and insufficient weight to events with high probability. | https://en.wikipedia.org/wiki?curid=197284 | 159,474 |
162,166 | While the Wall St Crash of 1929 had little direct impact on the British stock market, the collapse of the American economy which it had foretold and the associated contraction of world trade seriously affected Britain in the early 1930s. Whereas British politicians had championed the concept of the free market when it was ascendant in the world economy, it gradually withdrew to adopting Tariff Reform as a measure of protectionism. In 1933 Sterling left the Gold Standard. By the early 1930s, the depression again signalled the economic problems the British economy faced. Unemployment soared during this period; from just over 10% in 1929 to more than 20% (or more than 3 million of the workforce) by early 1933. However, it had fallen to 13.9% by the start of 1936. While heavy industry sank to new lows, the consumer industry recovered by 1934 and production increased by 32% between 1933 and 1937. A good indication of the strong consumer market was the growth of retailers during the 1930s. Marks & Spencer, for example, increased its turnover from £2.5 million in 1929 to over £25 million in 1939, necessitating the opening of dozens of new locations to serve the burgeoning demand in the suburbs. | https://en.wikipedia.org/wiki?curid=33643110 | 162,081 |
792,946 | Since the late 1990s amateurs have been following the professional observatories in the switch from film to digital CCDs for astronomical imaging. CCDs are more sensitive than film, allowing much shorter exposure times, and have a linear response to light. Images can be captured in many short exposures to create a synthetic long exposure. Digital cameras also have minimal or no moving parts and the ability to be operated remotely via an infrared remote or computer tethering, limiting vibration. Simple digital devices such as webcams can be modified to allow access to the focal plane and even (after the cutting of a few wires), for long exposure photography. Digital video cameras are also used. There are many techniques and pieces of commercially manufactured equipment for attaching digital single-lens reflex (DSLR) cameras and even basic point and shoot cameras to telescopes. Consumer-level digital cameras suffer from image noise over long exposures, so there are many techniques for cooling the camera, including cryogenic cooling. Astronomical equipment companies also now offer a wide range of purpose-built astronomical CCD cameras complete with hardware and processing software. Many commercially available DSLR cameras have the ability to take long time exposures combined with sequential (time-lapse) images allowing the photographer to create a motion picture of the night sky. | https://en.wikipedia.org/wiki?curid=143115 | 792,521 |
623,804 | Phosphorus is a nutrient that occurs in many forms that are bioavailable. It is notoriously over-abundant in human sewage sludge. It is a main ingredient in many fertilizers used for agriculture as well as on residential and commercial properties, and may become a limiting nutrient in freshwater systems and some estuaries. Phosphorus is most often transported to water bodies via soil erosion because many forms of phosphorus tend to be adsorbed on to soil particles. Excess amounts of phosphorus in aquatic systems (particularly freshwater lakes, reservoirs, and ponds) leads to proliferation of microscopic algae called phytoplankton. The increase of organic matter supply due to the excessive growth of the phytoplankton is called eutrophication. A common symptom of eutrophication is algae blooms that can produce unsightly surface scums, shade out beneficial types of plants, produce taste-and-odor-causing compounds, and poison the water due to toxins produced by the algae. These toxins are a particular problem in systems used for drinking water because some toxins can cause human illness and removal of the toxins is difficult and expensive. Bacterial decomposition of algal blooms consumes dissolved oxygen in the water, generating hypoxia with detrimental consequences for fish and aquatic invertebrates. | https://en.wikipedia.org/wiki?curid=4146576 | 623,472 |
263,577 | The name "silicosis" (from the Latin "silex", or flint) was originally used in 1870 by Achille Visconti (1836–1911), prosector in the Ospedale Maggiore of Milan. The recognition of respiratory problems from breathing in dust dates to ancient Greeks and Romans. Agricola, in the mid-16th century, wrote about lung problems from dust inhalation in miners. In 1713, Bernardino Ramazzini noted asthmatic symptoms and sand-like substances in the lungs of stone cutters. With industrialization, as opposed to hand tools, came increased production of dust. The pneumatic hammer drill was introduced in 1897 and sandblasting was introduced in about 1904, both significantly contributing to the increased prevalence of silicosis. In 1938, the United States Department of Labor, led by then Secretary of Labor, Frances Perkins, produced a video titled 'Stop Silicosis' to discuss the results of a year-long study done concerning a rise in the number of silicosis cases across the United States. | https://en.wikipedia.org/wiki?curid=633241 | 263,434 |
1,953,297 | where R is the fraction of SE that arrives at the anode inside radius r, V the potential difference between the electrodes placed at distance d, k is Boltzmann's constant, T the absolute gas temperature, e the electron charge and ε is the ratio of the thermal (agitation and kinetic) energy of the electrons divided by the thermal energy of the host gas; I is the corresponding current collected by the anode inside r, δ is the SE yield coefficient and I the incident electron beam current. This provides the spatial distribution of the initial electrons SE as they are acted upon by the uniform electric field that moves them from the cathode to the anode, while the electrons also diffuse away due to thermal collisions with the gas molecules. Plots are provided in the accompanying , for a set of operating conditions of pressure p and distance d. We note that a 100% collection efficiency is fast approached within a small radius even at moderate field strength. At high bias, a nearly complete collection is achieved within a very small radius, a fact that has favorable design implications. | https://en.wikipedia.org/wiki?curid=22712749 | 1,952,176 |
817,034 | The first mission of the "Seiran" squadron, which was named the was to be a surprise air strike on the Gatun locks of the Panama Canal, to cut the main supply line for US forces in the Pacific. When the force was finally ready to set off on their mission against Panama, Japan's increasingly desperate situation led to a change in plan, with the target for the attack, called Operation "Hikari" (Splendour), being switched to the American base at Ulithi Atoll where forces, including aircraft carriers, were massing in preparation for attacks on the Japanese Home Islands. The flotilla departed Japan on 23 July 1945 and proceeded towards Ulithi. On 16 August, the flagship "I-401" received a radio message from headquarters, informing them of Japan's surrender and ordering them to return to Japan. All six "Seirans" on board the two submarines, having been disguised for the operation as American planes in violation of the laws of war, were catapulted into the sea with their wings and stabilizers folded (for the "I-401") or pushed overboard (for the "I-400)" to prevent capture. | https://en.wikipedia.org/wiki?curid=597250 | 816,598 |
80,046 | On land, pinnipeds are near-sighted in dim light. This is reduced in bright light, as the retracted pupil reduces the lens and cornea's ability to bend light. They also have a well-developed "tapetum lucidum", a reflecting layer that increases sensitivity by reflecting light back through the rods. This helps them see in low-light conditions. Ice-living seals like the harp seal have corneas that can tolerate high levels of ultraviolet radiation typical of bright, snowy environments. As such, they do not suffer snow blindness. Pinnipeds appear to have limited color vision, as they lack S-cones. Flexible eye movement has been documented in seals. The extraocular muscles of the walrus are well developed. This and its lack of orbital roof allow it to protrude its eyes and see in both frontal and dorsal directions. Seals release large amounts of mucus to protect their eyes. The corneal epithelium is keratinized and the sclera is thick enough to withstand the pressures of diving. As in many mammals and birds, pinnipeds possess nictitating membranes. | https://en.wikipedia.org/wiki?curid=60261 | 80,013 |
232,560 | As a result of the Energy Independence and Security Act of 2007, which mandates an increase in renewable fuels for the transport sector, the U.S. Department of Energy began assessments for the feasibility of using intermediate ethanol blends in the existing vehicle fleet as a way to allow higher consumption of ethanol fuel. The National Renewable Energy Laboratory (NREL) conducted tests to evaluate the potential impacts of intermediate ethanol blends on legacy vehicles and other engines. In a preliminary report released in October 2008, the NREL presented the results of the first evaluations of the effects of E10, E15 and E20 gasoline blends on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials. This preliminary report found none of the vehicles displayed a malfunction indicator light as a result of the ethanol blend used; no fuel filter plugging symptoms were observed; no cold start problems were observed at and laboratory conditions; and as expected, computer technology available in newer model vehicles adapts to the higher octane causing lower emissions with greater horsepower and in some cases greater fuel economy. | https://en.wikipedia.org/wiki?curid=2155310 | 232,441 |
1,453,803 | The surrounding blanket can be a fissile material (enriched uranium or plutonium) or a fertile material (capable of conversion to a fissionable material by neutron bombardment) such as thorium, depleted uranium or spent nuclear fuel. Such subcritical reactors (which also include particle accelerator-driven neutron spallation systems) offer the only currently-known means of active disposal (versus storage) of spent nuclear fuel without reprocessing. Fission by-products produced by the operation of commercial light water nuclear reactors (LWRs) are long-lived and highly radioactive, but they can be consumed using the excess neutrons in the fusion reaction along with the fissionable components in the blanket, essentially destroying them by nuclear transmutation and producing a waste product which is far safer and less of a risk for nuclear proliferation. The waste would contain significantly reduced concentrations of long-lived, weapons-usable actinides per gigawatt-year of electric energy produced compared to the waste from a LWR. In addition, there would be about 20 times less waste per unit of electricity produced. This offers the potential to efficiently use the very large stockpiles of enriched fissile materials, depleted uranium, and spent nuclear fuel. | https://en.wikipedia.org/wiki?curid=20766780 | 1,452,986 |
494,441 | After setting the world record in a near time trial in 2020, Joshua Cheptegei was the overwhelming favorite. Mo Farah, the London 2012 and Rio 2016 Olympic champion, had failed to meet the Olympic qualifying standard. Bronze medalist Hagos Gebrhiwet also did not return, but silver medalist Paul Chelimo was back for another go. None of the Ethiopian medalists from the World Championships came, but Canadian World Championship bronze medalist Mohammed Ahmed was. The Ugandan team came in force again to play team tactics that didn't quite get the desired results in the 10,000 earlier in the week, while Ethiopia only qualified one athlete into the final and Kenya two. An additional unknown was the find of the season Mohamed Katir who ran historical times in the 1500, 3000 and 5000 in the run up to the Olympics. Nobody, not even Katir, knew what kind of kick he would have if he were still in contention at the end. It is already almost predetermined a major championship race will go down to a last lap kick. Tactics are involved to try to keep the number fighting on that final lap to a minimum. | https://en.wikipedia.org/wiki?curid=60376619 | 494,186 |
550,226 | In 1935, Vladimir Fock showed that the quantum mechanical bound Kepler problem is equivalent to the problem of a free particle confined to a three-dimensional unit sphere in four-dimensional space. Specifically, Fock showed that the Schrödinger wavefunction in the momentum space for the Kepler problem was the stereographic projection of the spherical harmonics on the sphere. Rotation of the sphere and re-projection results in a continuous mapping of the elliptical orbits without changing the energy, an SO(4) symmetry sometimes known as Fock symmetry; quantum mechanically, this corresponds to a mixing of all orbitals of the same energy quantum number "n". Valentine Bargmann noted subsequently that the Poisson brackets for the angular momentum vector L and the scaled LRL vector A formed the Lie algebra for SO(4). Simply put, the six quantities A and L correspond to the six conserved angular momenta in four dimensions, associated with the six possible simple rotations in that space (there are six ways of choosing two axes from four). This conclusion does not imply that our universe is a three-dimensional sphere; it merely means that this particular physics problem (the two-body problem for inverse-square central forces) is "mathematically equivalent" to a free particle on a three-dimensional sphere. | https://en.wikipedia.org/wiki?curid=719460 | 549,938 |
588,719 | Formal study of runway incursions began in the 1980s, following several high-profile near misses and fatal collisions of airliners operating on airport surfaces. One of the earliest reports on the topic was published in 1986 by the American National Transportation Safety Board (NTSB), titled "Runway Incursions at Controlled Airports in the United States". Citing examples like the Tenerife airport disaster and the 1972 Chicago–O'Hare runway collision, a special investigation was opened "to investigate selected runway incursions to determine their underlying causes and to recommend appropriate remedial actions." After detailed examination of 26 incursion incidents occurring in 1985, investigators compiled a list of conclusions and safety recommendations. Among their findings were a need for clearer airport signage, improved controller supervision, and revised training procedures for aircrews and controllers. Despite the valuable data generated by the investigation, the NTSB conceded that, at the time, "the magnitude of the runway incursion problem could not be measured because of both incomplete reporting and follow-up investigations by the FAA." | https://en.wikipedia.org/wiki?curid=10758386 | 588,417 |
452,449 | Field experiments can be expensive, time-consuming to conduct, difficult to replicate, and plagued with ethical pitfalls. Subjects or populations might undermine the implementation process if there is a perception of unfairness in treatment selection (e.g. in 'negative income tax' experiments communities may lobby for their community to get a cash transfer so the assignment is not purely random). There are limitations to collecting consent forms from all subjects. Comrades administering interventions or collecting data could contaminate the randomization scheme. The resulting data, therefore, could be more varied: larger standard deviation, less precision and accuracy, etc. This leads to the use of larger sample sizes for field testing. However, others argue that, even though replicability is difficult, if the results of the experiment are important then there a larger chance that the experiment will get replicated. As well, field experiments can adopt a "stepped-wedge" design that will eventually give the entire sample access to the intervention on different timing schedules. Researchers can also design a blinded field experiment to remove possibilities of manipulation. | https://en.wikipedia.org/wiki?curid=1305037 | 452,230 |
1,690 | To support his new strategy, Kennedy ordered a massive increase in defense spending. He sought, and Congress provided, a rapid build-up of the nuclear arsenal to restore the lost superiority over the Soviet Union—he claimed in 1960 that Eisenhower had lost it because of excessive concern with budget deficits. In his inaugural address, Kennedy promised "to bear any burden" in the defense of liberty, and he repeatedly asked for increases in military spending and authorization of new weapons systems. From 1961 to 1964 the number of nuclear weapons increased by 50 percent, as did the number of B-52 bombers to deliver them. The new ICBM force grew from 63 intercontinental ballistic missiles to 424. He authorized 23 new Polaris submarines, each of which carried 16 nuclear missiles. He called on cities to prepare fallout shelters for nuclear war. In contrast to Eisenhower's warning about the perils of the military–industrial complex, Kennedy focused on arms buildup. | https://en.wikipedia.org/wiki?curid=325329 | 1,690 |
1,101,847 | Production of many metals (cast iron, grey iron, ductile iron, compacted graphite iron, 3000 series aluminium alloys, copper alloys, silver, and complex steels) are aided by a production technique also referred to as thermal analysis. A sample of liquid metal is removed from the furnace or ladle and poured into a sample cup with a thermocouple embedded in it. The temperature is then monitored, and the phase diagram arrests (liquidus, eutectic, and solidus) are noted. From this information chemical composition based on the phase diagram can be calculated, or the crystalline structure of the cast sample can be estimated especially for silicon morphology in hypo-eutectic Al-Si cast alloys. Strictly speaking these measurements are "cooling curves" and a form of sample controlled thermal analysis whereby the cooling rate of the sample is dependent on the cup material (usually bonded sand) and sample volume which is normally a constant due to the use of standard sized sample cups. To detect phase evolution and corresponding characteristic temperatures, cooling curve and its first derivative curve should be considered simultaneously. Examination of cooling and derivative curves is done by using appropriate data analysis software. The process consists of plotting, smoothing and curve fitting as well as identifying the reaction points and characteristic parameters. This procedure is known as Computer-Aided Cooling Curve Thermal Analysis. | https://en.wikipedia.org/wiki?curid=258833 | 1,101,286 |
94,572 | Reptiles are a class of animals comprising turtles, tuataras, lizards, snakes and crocodiles. They are tetrapods, but the snakes and a few species of lizard either have no limbs or their limbs are much reduced in size. Their bones are better ossified and their skeletons stronger than those of amphibians. The teeth are conical and mostly uniform in size. The surface cells of the epidermis are modified into horny scales which create a waterproof layer. Reptiles are unable to use their skin for respiration as do amphibians and have a more efficient respiratory system drawing air into their lungs by expanding their chest walls. The heart resembles that of the amphibian but there is a septum which more completely separates the oxygenated and deoxygenated bloodstreams. The reproductive system has evolved for internal fertilization, with a copulatory organ present in most species. The eggs are surrounded by amniotic membranes which prevents them from drying out and are laid on land, or develop internally in some species. The bladder is small as nitrogenous waste is excreted as uric acid. | https://en.wikipedia.org/wiki?curid=674 | 94,531 |
189,083 | His first paper in 1825 examined the decrease in the electromagnetic force produced by a wire as the length of the wire increased. In 1826, he gave a description of conduction in circuits modelled on Fourier's study of heat conduction. This paper continued Ohm's deduction of results from experimental evidence and, particularly in the second, he was able to propose laws which went a long way to explaining results of others working on galvanic electricity. The most important was his pamphlet published in Berlin in 1827, with the title "Die galvanische Kette mathematisch bearbeitet". This work, the germ of which had appeared during the two preceding years in the journals of Schweigger and Poggendorff, has exerted an important influence on the development of the theory and applications of electric current. Ohm's name has been incorporated in the terminology of electrical science in Ohm's Law (which he first published in "Die galvanische Kette"...), the proportionality of current and voltage in a resistor, and adopted as the SI unit of resistance, the ohm (symbol Ω). | https://en.wikipedia.org/wiki?curid=49080 | 188,986 |
343,682 | However, the application of standardized Piagetian theory and procedures in different societies established widely varying results that lead some to speculate not only that some cultures produce more cognitive development than others but that without specific kinds of cultural experience, but also formal schooling, development might cease at certain level, such as concrete operational level. A procedure was done following methods developed in Geneva (i.e. water level task). Participants were presented with two beakers of equal circumference and height, filled with equal amounts of water. The water from one beaker was transferred into another with taller and smaller circumference. The children and young adults from non-literate societies of a given age were more likely to think that the taller, thinner beaker had more water in it. On the other hand, an experiment on the effects of modifying testing procedures to match local cultural produced a different pattern of results. In the revised procedures, the participants explained in their own language and indicated that while the water was now "more", the quantity was the same. Piaget's water level task has also been applied to the elderly by Formann and results showed an age-associated non-linear decline of performance. | https://en.wikipedia.org/wiki?curid=1058599 | 343,501 |
859,379 | As the use of industrial automation has expanded over time, some factories have begun to approach a semblance of self-sufficiency that is suggestive of self-replicating machines. However, such factories are unlikely to achieve "full closure" until the cost and flexibility of automated machinery comes close to that of human labour and the manufacture of spare parts and other components locally becomes more economical than transporting them from elsewhere. As Samuel Butler has pointed out in "Erewhon", replication of partially closed universal machine tool factories is already possible. Since safety is a primary goal of all legislative consideration of regulation of such development, future development efforts may be limited to systems which lack either control, matter, or energy closure. Fully capable machine replicators are most useful for developing resources in dangerous environments which are not easily reached by existing transportation systems (such as outer space). | https://en.wikipedia.org/wiki?curid=1600053 | 858,921 |
1,355,264 | On 27 August,"Trout", now under the command of Lt. Cdr. Lawson Paterson "Red" Ramage, proceeded to Australia via the Marshall and Caroline Islands. She began patrolling the southern approaches to Truk on 7 September and was detected by three patrol craft on 10 September, apparently triangulating her position using radar. Forced to go deep for one and a half hours, "Trout" was attacked by 45 depth charges. The next day, she sighted a large transport but escorts forced her to go deep and clear the area. On 21 September, the submarine fired three stern torpedoes at a naval auxiliary. The first torpedo broke the ship in half and the next two hit the aft section. The victim was subsequently identified as "Koei Maru", a converted net tender of 900 tons. A week later, "Trout" picked up a carrier group consisting of an escort carrier, two cruisers, and two destroyers. The submarine closed to and fired a spread of five torpedoes. She heard two timed explosions and saw the carrier | https://en.wikipedia.org/wiki?curid=430381 | 1,354,516 |
833,569 | Noddack's article was read by Fermi's team in Rome, Curie and Joliot in Paris, and Meitner and Hahn in Berlin. However, the quoted objection comes some distance down, and is but one of several gaps she noted in Fermi's claim. Bohr's liquid drop model had not yet been formulated, so there was no theoretical way to calculate whether it was physically possible for the uranium atoms to break into large pieces. Noddack and her husband, Walter Noddack, were renowned chemists who had been nominated for the Nobel Prize in Chemistry for the discovery of rhenium, although at the time they were also embroiled in a controversy over the discovery of element 43, which they called "masurium". The discovery of technetium by Emilio Segrè and Carlo Perrier put an end to their claim, but did not occur until 1937. It is unlikely that Meitner or Curie had any prejudice against Noddack because of her sex, but Meitner was not afraid to tell Hahn "Hähnchen, von Physik verstehst Du Nichts" ("Hahn dear, of physics you understand nothing"). The same attitude carried over to Noddack, who did not propose an alternative nuclear model, nor conduct experiments to support her claim. Although Noddack was a renowned analytical chemist, she lacked the background in physics to appreciate the enormity of what she was proposing. | https://en.wikipedia.org/wiki?curid=64011351 | 833,120 |
1,036,358 | After completing his doctoral dissertation on the theory of superconductivity, Schrieffer spent the 1957–1958 academic year as a National Science Foundation fellow at the University of Birmingham in England and at the Niels Bohr Institute in Copenhagen, where he continued research into superconductivity. Following a year as assistant professor at the University of Chicago, he returned to the University of Illinois in 1959 as a faculty member. In 1960, he went back to the Bohr Institute for a summer visit, during which he became engaged to Anne Grete Thomsen whom he married at Christmas of that year. Two years later, Schrieffer joined the faculty of the University of Pennsylvania in Philadelphia, and, in 1964, Schrieffer published his book on the BCS theory, Theory of Superconductivity. He held honorary degrees from the Technical University of Munich and the University of Geneva. In 1968 Schrieffer, along with Cooper, were awarded the Comstock Prize in Physics from the National Academy of Sciences. He was awarded the Oliver E. Buckley Condensed Matter Prize by the American Physical Society the same year. | https://en.wikipedia.org/wiki?curid=396615 | 1,035,818 |
1,461,495 | An example of this division is found in a study and discussion on personal and extrapersonal attention, where personal relates to the body's sense of itself (the body schema) and extrapersonal relates to all external of such. Some research supports the claim that these two categories are purely distinct and do not intermingle, contrary to what the extended body schema theory describes. Evidence for such is primarily found in subjects with unilateral neglect, such as in the case of E.D.S., who was a middle-aged man with right hemisphere brain damage. When he was tested for hemispatial neglect using traditional measures such as sentence reading and cancellation tests, E.D.S. showed few signs and upon later examination showed no signs whatsoever, leading doctors to believe he was normal. However, he constantly had issues with physical therapy because he would claim to not be able to see his left leg; upon further examination, E.D.S. was known to have a particular type of hemispatial neglect that only affected the perception of his body. The motor function of the left side of his body was negatively affected though not totally compromised, yet when attempting tasks such as shaving, he would invariably not shave the left side of his face. This led some researchers to believe that there is a distinction between personal and extrapersonal neglect, which would thus reflect a similar distinction with body schema itself. | https://en.wikipedia.org/wiki?curid=14782003 | 1,460,673 |
1,396,391 | In early stages of the disease of PMC, many studies have speculated that TcdA is more potent than TcdB. This has been deduced from in vivo experiments where toxin productions of TcdA were more severe than TcdB with antibiotics cecitis. Later, several studies showed that TcdB plays a major role in the disease of PMC and ADD. The study demonstrated that even though "C. difficile" did not produces TcdA, it still showed symptoms for the disease. Furthermore, later studies have shown that a purified form of TcdB is a more lethal enterotoxin in comparison to TcdA, and also, that intestinal epithelium is severely damaged and causes an acute inflammatory response. With better understanding of the toxin, researchers were able to state that TcdB is the major virulence factor that causes CDI over TcdA. However, when TcdA is present in the gut, it helps to facilitate TcdB's activity to have broader impacts, consequently, affecting multiple organ systems. In addition, when hamsters were vaccinated against TcdA, it showed hamsters were not fully protected from the "C. difficile" disease and this lead studies to conclude that TcdB is very lethal and potent. Furthermore, injecting a small dose of TcdA with a lethal dose of TcdB intravenously or intraperitoneally proved sufficient in causing the death of an animal. Therefore, TcdA works as a facilitator of TcdB exiting from the gut. | https://en.wikipedia.org/wiki?curid=20637113 | 1,395,620 |
1,831,857 | The Underground Research Laboratory was a test site for deep geological repository of nuclear waste operated by Atomic Energy of Canada Limited's (AECL's) Whiteshell Laboratories near Lac du Bonnet in Manitoba, Canada. The site was built inside a large granite batholith, typical of the Canadian Shield. The site was selected in 1980, construction began in 1982 and it opened in 1985. No radioactive material was stored at the site, it was used purely for measurements of water exchange, rock movement, and other issues that would affect the safety of such materials. The site was also used by a variety of international users. As part of the wider wind-down of AECL activities, the decision was made to close the URL in 2003. Cleanup work began in 2006 and completed in 2010. The site continues to host a single international experiment measuring water leakage through a massive clay plug. | https://en.wikipedia.org/wiki?curid=55998829 | 1,830,810 |
645,470 | More than 50 genes have been examined in association studies with hypertension, and the number is constantly growing. One of these genes is the angiotensinogen (AGT) gene, studied extensively by Kim et al. They showed that increasing the number of AGT increases the blood pressure and hence this may cause hypertension. In single variant tests, it has been shown that SNPs were enriched for variants associated with adiposity, type 2 diabetes, coronary heart disease and kidney function in previously published GWAS, providing evidence that genetic loci related to blood pressure contribute to cardiovascular outcomes. Twins have been included in studies measuring ambulatory blood pressure; from these studies it has been suggested that there is a large genetic influence on essential hypertension. Supporting data has emerged from animal studies as well as clinical studies in human populations. The majority of these studies support the concept that the inheritance is probably multifactorial or that a number of different genetic defects each has an elevated blood pressure as one of its phenotypic expressions. However, the genetic influence on hypertension is not fully understood at the moment. It is believed that linking hypertension-related phenotypes with specific variations of the genome may yield definitive evidence of heritability. Another view is that hypertension can be caused by mutations in single genes, inherited on a Mendelian basis. | https://en.wikipedia.org/wiki?curid=841093 | 645,130 |
1,725,673 | In nature, "Suillus spraguei" forms ectomycorrhizal relationships with five-needled pine species. This is a mutually beneficial relationship where the hyphae of the fungus grow around the roots of the trees, enabling the fungus to receive moisture, protection and nutritive byproducts of the tree, and affording the tree greater access to soil nutrients. "S. spraguei" produces tuberculate ectomycorrhizae (covered with wart-like projections) that are described as aggregates of ectomycorrhizal roots encased in a fungal rind, and rhizomorphs that are tubular fungal cords with a hard outer sheath. The fungus has ecological host specificity, and in natural soils can only associate with white pine, a grouping of trees classified in subgenus "Strobus" of the genus "Pinus". Under controlled pure culture conditions in the laboratory, "S. spraguei" has also been shown to form associations with red pine, pitch pine, and loblolly pine. Asian populations have been associated with Korean pine, Chinese white pine, Siberian dwarf pine and Japanese white pine. In North America, fruit bodies appear earlier than most other boletes, as early as June (bolete fruit bodies generally begin to appear in July–September), but they may be found as late as October. Mushrooms can be parasitized by the fungus "Hypomyces completus". In the asexual stage of "H. completus", it appears initially as patches of whitish mold on the surface of the cap or stem that rapidly spread to cover the entire mushroom surface and produce conidia (asexual spores). In the sexual stage, the mold changes color, progressing from yellow-brown to brown, greenish-brown and eventually black as it makes perithecia, asci-containing sexual structures that produce ascospores. The perithecia are pimply and give the surface a roughened texture. | https://en.wikipedia.org/wiki?curid=24547163 | 1,724,702 |
1,104,791 | The Extended Duration Orbiter (EDO) Pallet was a 15-foot (4.6 m) diameter cryo-kit wafer structure. Weighing , it provided support for tanks, associated control panels, and avionics equipment. The tanks stored of liquid hydrogen at −250 degrees Celsius, and of liquid oxygen at −176 degrees Celsius. The total empty mass of the system was . When filled with cryogens, system mass was approximately . Oxygen and hydrogen were supplied to the orbiter's three electrical power generating fuel cells, where they were converted into sufficient electrical energy to support the average four family-member house for approximately six months. About of pure drinking water was also produced by the fuel cells. With the EDO pallet, the orbiter could support a flight for a maximum of 18 days. Longer on-orbit missions benefit microgravity research, life sciences research, Earth and celestial observations, human adaptation to the zero-G environment, and support to the Space Station. | https://en.wikipedia.org/wiki?curid=557153 | 1,104,228 |
852,866 | Although there is no direct evidence of a SHH gradient, there is indirect evidence via the visualization of Patched ("Ptc") gene expression, which encodes for the ligand binding domain of the SHH receptor throughout the ventral neural tube. "In vitro" studies show that incremental two- and threefold changes in SHH concentration give rise to motor neuron and different interneuronal subtypes as found in the ventral spinal cord. These incremental changes "in vitro" correspond to the distance of domains from the signaling tissue (notochord and floor plate) which subsequently differentiates into different neuronal subtypes as it occurs "in vitro". Graded SHH signaling is suggested to be mediated through the Gli family of proteins, which are vertebrate homologues of the "Drosophila" zinc-finger-containing transcription factor "Cubitus interruptus" ("Ci"). "Ci" is a crucial mediator of hedgehog ("Hh") signaling in "Drosophila". In vertebrates, three different Gli proteins are present, viz. Gli1, Gli2 and Gli3, which are expressed in the neural tube. Mice mutants for Gli1 show normal spinal cord development, suggesting that it is dispensable for mediating SHH activity. However, Gli2 mutant mice show abnormalities in the ventral spinal cord, with severe defects in the floor plate and ventral-most interneurons (V3). Gli3 antagonizes SHH function in a dose-dependent manner, promoting dorsal neuronal subtypes. SHH mutant phenotypes can be rescued in a SHH/Gli3 double mutant. Gli proteins have a C-terminal activation domain and an N-terminal repressive domain. | https://en.wikipedia.org/wiki?curid=353697 | 852,412 |
677,835 | Yield management has significantly altered the travel and hospitality industry since its inception in the mid-1980s. It requires analysts with detailed market knowledge and advanced computing systems who implement sophisticated mathematical techniques to analyze market behavior and capture revenue opportunities. It has evolved from the system airlines invented as a response to deregulation and quickly spread to hotels, car rental firms, cruise lines, media, telecommunications and energy to name a few. Its effectiveness in generating incremental revenues from an existing operation and customer base has made it particularly attractive to business leaders that prefer to generate return from revenue growth and enhanced capability rather than downsizing and cost cutting. | https://en.wikipedia.org/wiki?curid=1053994 | 677,481 |
1,069,403 | The height requirement was firm, an artifact of the size of the Apollo spacecraft. Candidates had to have copies of their academic transcripts from each university they had attended, along with Educational Testing Service scores and medical history were sent directly to the Astronaut Selection Board of the NAS by December 31, 1964, along with medical examination results. In addition, they could send supporting materials, which might include papers they had written, research they had conducted, or simply their thoughts about space science. They also had to be able to pass a Class I Military Flight Status Physical. This required 20/20 uncorrected vision. The helmets astronauts wore could not accommodate glasses, and contact lenses were considered to be unsuitable in space. | https://en.wikipedia.org/wiki?curid=3144242 | 1,068,849 |
1,237,012 | A cursorial, or "running" model was originally proposed by Samuel Wendell Williston in 1879. This theory states that "flight evolved in running bipeds through a series of short jumps". As the length of the jumps extended, the wings were used not only for thrust but also for stability, and eventually eliminated the gliding intermediate. This theory was modified in the 1970s by John Ostrom to describe the use of wings as an insect-foraging mechanism which then evolved into a wing stroke. Research was conducted by comparing the amount of energy expended by each hunting method with the amount of food gathered. The potential hunting volume doubles by running and jumping. To gather the same volume of food, "Archaeopteryx" would expend less energy by running and jumping than by running alone. Therefore, the cost/benefit ratio would be more favorable for this model. Due to "Archaeopteryx's" long and erect leg, supporters of this model say the species was a terrestrial bird. This characteristic allows for more strength and stability in the hindlimbs. Thrust produced by the wings coupled with propulsion in the legs generates the minimum velocity required to achieve flight. This wing motion is thought to have evolved from asymmetrical propulsion flapping motion. Thus, through these mechanisms, "Archaeopteryx" was able to achieve flight from the ground up. | https://en.wikipedia.org/wiki?curid=10589364 | 1,236,348 |
1,220,084 | With the publication of the 25th anniversary edition in 2000, the historians of biology Michael Yudell and Rob Desalle reviewed the nature-nurture controversy around the book. "Once again", they wrote, "biological reductionism and genetic determinism became the focus of rancorous debates, discussions and diatribes within both academia and popular culture." They pointed out that the quest for a "sociobiologization" of biology was not new, mentioning Darwin's "The Descent of Man", R.A. Fisher, and Julian Huxley, all touching on the biological basis of human society, followed by Konrad Lorenz, Desmond Morris and Robert Ardrey in the 1960s, and Richard Dawkins and David Barash in the 1970s. Wilson's choice of title echoed the modern synthesis (named by Huxley in 1942) and, the reviewers argued, meant to build upon and extend it. 25 years on, they noted, most of the discord had gone, and the discipline had been renamed as evolutionary psychology; they were surprised to find that Wilson was happy with that, and they called the new discipline pop psychology for people "who like telling just-so stories". | https://en.wikipedia.org/wiki?curid=1149054 | 1,219,430 |
1,092,925 | For molecular systems in thermal equilibrium, the addition of energy. e. g. by mechanical work, can cause a change in entropy. This is known from the theories of thermodynamics and statistical mechanics. Specifically, both theories assert that the change in energy must be proportional to the entropy change times the absolute temperature. This rule is only valid so long as the energy is restricted to thermal states of molecules. If a rubber sample is stretched far enough, energy may reside in non-thermal states such as the distortion of chemical bonds and the rule doesn't apply. At low to moderate strains, theory predicts that the required stretching force is due to a change in entropy in the network chains. If this is correct, then we expect that the force necessary to stretch a sample to some value of strain should be proportional to the temperature of the sample. Measurements showing how the tensile stress in a stretched rubber sample varies with temperature are shown in Fig. 4. In these experiments, the strain of a stretched rubber sample was held fixed as the temperature was varied between 10 and 70 degrees Celsius. For each value of fixed strain, it is seen that the tensile stress varied linearly (to within experimental error). These experiments provide the most compelling evidence that entropy changes are the fundamental mechanism for rubber elasticity. | https://en.wikipedia.org/wiki?curid=7623862 | 1,092,365 |
643,971 | The concept of bibliometrics "stresses the material aspect of the undertaking: counting books, articles, publications, citations" In theory, bibliometrics is a distinct field from "scientometrics" (from the Russian "naukometriya") which relies on the analysis of non-bibliographic indicators of scientific activity. In practice, bibliometrics and scientometrics studies tend to use similar data sources and methods, as citation data has become the leading standard of quantitative scientific evaluation during the mid-20th century: "insofar as bibliometric techniques are applied to scientific and technical literature, the two areas of scientometrics and bibliometrics overlap to a considerable degree." The development of the web and the expansion of bibliometrics approach to non-scientific production has entailed the introduction of broader labels in the 1990s and the 2000s: infometrics, webometrics or cybermetrics. These terms have not been extensively adopted, as they partly overlap with pre-existing research practices, such as information retrieval. | https://en.wikipedia.org/wiki?curid=1223245 | 643,631 |
1,237,013 | Although the evidence in favor of this model is scientifically plausible, the evidence against it is substantial. For instance, a cursorial flight model would be energetically less favorable when compared to the alternative hypotheses. In order to achieve liftoff, "Archaeopteryx" would have to run faster than modern birds by a factor of three, due to its weight. Furthermore, the mass of "Archaeopteryx" versus the distance needed for minimum velocity to obtain liftoff speed is proportional, therefore, as mass increases, the energy required for takeoff increases. Other research has shown that the physics involved in cursorial flight would not make this a likely answer to the origin of avian flight. Once flight speed is obtained and "Archaeopteryx" is in the air, drag would cause the velocity to instantaneously decrease; balance could not be maintained due to this immediate reduction in velocity. Hence, "Archaeopteryx" would have a very short and ineffective flight. In contrast to Ostrom's theory regarding flight as a hunting mechanism, physics again does not support this model. In order to effectively trap insects with the wings, "Archaeopteryx" would require a mechanism such as holes in the wings to reduce air resistance. Without this mechanism, the cost/benefit ratio would not be feasible. | https://en.wikipedia.org/wiki?curid=10589364 | 1,236,349 |
1,685,008 | These benefits are offset to a degree by the fact that organics also generally have a lower specific heat than water, and thus require higher flow rates to provide the same amount of cooling. A more significant problem was found in experimental devices; the high-energy neutrons given off as part of the nuclear reactions have much greater energy than the chemical bonds in the coolant, and they break the hydrocarbons apart. This results in the release of hydrogen and various shorter-chain hydrocarbons. The polymerization of the resulting products can turn into a thick tar-like state. Further, many suitable coolants are naturally flammable and sometimes toxic, which adds new safety concerns. Many uses of PCBs were banned beginning in the 1970s as their environmental toxicity was better understood. | https://en.wikipedia.org/wiki?curid=59149684 | 1,684,063 |
674,608 | Since 1990, Jansen has been creating "strandbeesten" (Dutch for "beach animals", singular "strandbeest"), which are moving kinetic structures, sometimes wind-propelled, that resemble walking animals, described by Jansen as artificial life. All of his models are based on a system of triangles and connecting links which convert the rotation of an axle into a stepping motion of six or more legs. This allows the strandbeesten to travel over sand much more efficiently than if it were to travel on wheels. What was at first a rudimentary "breed" has evolved slowly, with the help of evolutionary computation techniques, into a generation of kinetic sculptures that can react to their environment to some degree. According to Jansen, he was inspired by "The Blind Watchmaker" by Richard Dawkins. Jansen has said "I make skeletons that are able to walk on the wind. Over time, these skeletons have become increasingly better at surviving the elements such as storms and water and eventually I want to put these animals out in herds on the beaches, so they will live their own lives." | https://en.wikipedia.org/wiki?curid=1819917 | 674,255 |
2,202,342 | After the publication of in 1884, the book received different opinions. Some people were enthusiastic about it, while others refused the new viewpoints. Seven years earlier, the book ('"Comparative anatomy of the vegetative organs of the phanerogams and ferns"') by DeBarys was published. This book included twelve years of detailed research and was then thought to be the possible final statement on plant anatomy. Haberlandt was a young botanist with a new vision at the time, suggesting a connection between anatomy and physiology that cannot even be fully demonstrated through experiments. In those years science did not value analogies. Meanwhile analogies were a source of inspiration for Haberlandt. This book was intended mainly as an educational textbook. In the end it found resonance not only within Europe but also as far as Japan. After the first publications, Haberlandt's fellow scientists described the book as a botany novel and wanted to keep it away from their students to prevent heretical thoughts. This disagreement was also projected onto people who worked together with Haberlandt, like Schwendener. With each new edition of the book, Haberlandt referred back to those critics. The critics felt that it was too teleologically based and the author explained his distance from every form of vitalism multiple times. | https://en.wikipedia.org/wiki?curid=66293900 | 2,201,088 |
486,070 | Second-order cybernetics, also known as the cybernetics of cybernetics, is the recursive application of cybernetics to itself and the reflexive practice of cybernetics according to such a critique. It is cybernetics where "the role of the observer is appreciated and acknowledged rather than disguised, as had become traditional in western science". Second-order cybernetics was developed between the late 1960s and mid 1970s by Heinz von Foerster and others, with key inspiration coming from Margaret Mead. Foerster referred to it as "the control of control and the communication of communication" and differentiated first order cybernetics as "the cybernetics of observed systems" and second-order cybernetics as "the cybernetics of observing systems". It is closely allied to radical constructivism, which was developed around the same time by Ernst von Glasersfeld. While it is sometimes considered a break from the earlier concerns of cybernetics, there is much continuity with previous work and it can be thought of as a distinct tradition within cybernetics, with origins in issues evident during the Macy conferences in which cybernetics was initially developed. Its concerns include autonomy, epistemology, ethics, language, reflexivity, self-consistency, self-referentiality, and self-organizing capabilities of complex systems. It has been characterised as cybernetics where "circularity is taken seriously". | https://en.wikipedia.org/wiki?curid=2073462 | 485,821 |
2,045,871 | ESCAPE provides the first comprehensive study of the stellar EUV environments that control atmospheric mass-loss and determine the habitability of rocky exoplanets. ESCAPE’s prime mission is driven by two spectroscopic surveys: 1) a broad survey of EUV and FUV flux from 200 nearby (d < 100 pc) F, G, K, and M stars, providing direct input into atmospheric evolution models. The mission targets stars with a range of ages and activity levels, and places an emphasis on stars with known exoplanets. 2) A deep monitoring survey (~2 weeks per star) of 24 targets-of-interest to measure the stellar flare frequency distribution and constrain the coronal mass ejection (CME) rate and high-energy particle fluence from these objects. Together, these surveys provide the crucial stellar drivers that regulate habitable environments on planets targeted by upcoming atmospheric characterization missions, from James Webb Space Telescope to Large Ultraviolet Optical Infrared Surveyor. | https://en.wikipedia.org/wiki?curid=67130324 | 2,044,690 |
1,758,453 | Possible disease symptom is the development of Hereditary tyrosinemia type 1 (HT1). Caused by the lack of fumarylacetoacetate hydrolase (FAH), the last enzyme of the tyrosine catabolic pathway, HT 1 is inherited as a rare autosomal recessive disease with a prevalence in Europe of 1 : 50000. However, in isolated parts of Quebec's provinces, the frequency can be as high as 1 : 2000 with a carrier rate of 1:20 possibly due to a single founder mutation. FAH deficiency leads to an accumulation of alkylafing metabolites that cause damage to the liver. The disorder presents as an acute, chronic or intermediate mild phenotype. The acute form manifests itself within the first half year and is characterized by liver failure, renal damage, and possibly death in the first year of life. The chronic form has an age of onset of more than one year after birth; rickets and progressive liver disease often lead to the development of hepatocellular carcinoma. Other symptoms can include renal tubular injury, hepatic necrosis, episodic weakness, seizures. Renal Fanconi syndrome and Porphyric crises are also cited in addition to liver and renal damage. | https://en.wikipedia.org/wiki?curid=11444686 | 1,757,460 |
637,985 | As early as 1984, scientists reported seeing herpesvirus-like structures in KS tumors examined under electron microscopy. Scientists had been searching for the agent causing KS, and over 20 agents were proposed as the possible cause, including cytomegalovirus and HIV itself. The pathogen was ultimately identified in 1994 by Yuan Chang and Patrick S. Moore, a wife and husband team at Columbia University, through the isolation of DNA fragments from a herpesvirus found in a KS tumor in an AIDS patient. Chang and Moore used representational difference analysis, or RDA, to find KSHV by comparing KS tumor tissue from an AIDS patient to his own unaffected tissue. The idea behind this experiment was that if a virus causes KS, the genomic DNA in the two samples should be precisely identical except for DNA belonging to the virus. In their initial RDA experiment, they isolated two small DNA fragments that represented less than 1% of the actual viral genome. These fragments were similar (but still distinct from) the known herpevirus sequences, indicating the presence of a new virus. Starting from these fragments, this research team was then able to sequence the entire genome of the virus less than two years later. | https://en.wikipedia.org/wiki?curid=1247939 | 637,646 |
1,307,336 | Félix Candela worked as an architect upon his arrival in Mexico until 1949 when he started to engineer many concrete structures utilizing his well-known thin-shell design. Candela did most of his work in Mexico throughout the 1950s and into the late 60s. He was responsible for more than 300 works and 900 projects in this time period. Many of his larger projects were given to him by the Mexican government, such as the Cosmic Rays Pavilion. In 1956, Mexican President Adolfo Ruiz Cortines said "Nothing could be more serious than to sit in the shade of the buildings we are about to build," foreshadowing the many construction projects to come. Ruiz Cortines came up with a budget to enable his construction declaration to come true, requesting ₱81,200,000 (pesos) more funding than was used in 1955. Luckily for Candela, ₱20,300,000 (pesos) of this funding was to go towards public works. Candela also benefited from the budget implemented by Ruiz Cortines in the area of education. Candela became a professor in Mexico, which is what he did for the remainder of his career. Felix moved to the United States and taught at University of Illinois at Chicago from 1971 to 1978. | https://en.wikipedia.org/wiki?curid=4828018 | 1,306,620 |
1,831,024 | A mechanochemical based model for primary neural induction was first proposed in 1985 by Brodland and Gordon. They proposed that there is a mechanically sensitive bistable organelle made of microtubules and microfilaments in the apical ends of cells within cell sheets that are about to differentiate (that are competent) and these cells are under mechanical tension. The microtubules and microfilaments are in mechanical opposition in a proposed embryonic organelle they called the cell state splitter. Depending on where the cell is within a sheet, the tension will be resolved by either the apical end contracting or the apical end expanding. The resolution will begin at one point and spread over the rest of the tissue limited by other mechanical forces at boundaries. An actual physical wave of contraction has been found which traverses the presumptive neural epithelium of the developing salamander, the axolotl ("Ambystoma mexicanum"). The contraction wave's trajectory was more complex than predicted in the original model however it did originate from the precise location of the Spemann organizer and traversed only the presumptive neural epithelium. Electron microscopy showed intermediate filaments are also present in the cell state splitter. Additional waves of both contraction and expansion were also discovered by time lapse photography of axolotl gastrulation. Among them was a wave of expansion that occurs in ectoderm only in the presumptive epithelium. When the trajectories of the waves were superimposed on the fate map of the axolotl it was shown that there is a unique combination of expansion and contraction waves that correlates with the tissue types determined during gastrulation and that this set of wave trajectories could explain the shape of the fate map. | https://en.wikipedia.org/wiki?curid=55661946 | 1,829,978 |
1,033,919 | As earlier stated, flow instruments that function with the separator in an oil and gas environment include the flow indicator, flow transmitter and the flow controller. Due to maintenance (which will be discussed later) or due to high usage, these flowmeters do need to be calibrated from time to time. Calibration can be defined as the process of referencing signals of known quantity that has been predetermined to suit the range of measurements required. Calibration can also be seen from a mathematical point of view in which the flowmeters are standardized by determining the deviation from the predetermined standard so as to ascertain the proper correction factors. In determining the deviation from the predetermined standard, the actual flowrate is usually first determined with the use of a master meter which is a type of flowmeter that has been calibrated with a high degree of accuracy or by weighing the flow so as to be able to obtain a gravimetric reading of the mass flow. Another type of meter used is the transfer meter. However, according to Ting "et al" (1989), transfer meters have been proven to be less accurate if the operating conditions are different from its original calibrated points. According to Yoder (2000), the types of flowmeters used as master meters include turbine meters, positive displacement meters, venturi meters, and Coriolis meters. In the U.S., master meters are often calibrated at a flow lab that has been certified by the National Institute of Standards and Technology, (NIST). NIST certification of a flowmeter lab means that its methods have been approved by NIST. Normally, this includes NIST traceability, meaning that the standards used in the flowmeter calibration process have been certified by NIST or are causally linked back to standards that have been approved by NIST. However, there is a general belief in the industry that the second method which involves the gravimetric weighing of the amount of fluid (liquid or gas) that actually flows through the meter into or out of a container during the calibration procedure is the most ideal method for measuring the actual amount of flow. Apparently, the weighing scale used for this method also has to be traceable to the National Institute of Standards and Technology (NIST) as well. | https://en.wikipedia.org/wiki?curid=10980696 | 1,033,382 |
1,124,336 | Early computer games began to be created in the 1950s, and the steady increase in the number and abilities of computers over time led to the gradual loosening of restrictions on access to mainframe computers at academic and corporate institutions beginning in the 1960s. This in turn led to a modest proliferation of generally small, text-based games on mainframe computers, with increasing complexity towards the end of the decade. While games continued to be developed on mainframes and minicomputers through the 1970s, the rise of personal computers and the spread of high-level programming languages meant that later games were generally intended to or were capable of being run on personal computers, even when developed on a mainframe. These early games include "Hamurabi", an antecedent of the strategy and city-building genres; "Lunar Lander", which inspired numerous recreations in the 1970s and 1980s; "Civil War", an early war simulation game; "Star Trek", which was widely ported, expanded, and spread for decades after; "Space Travel", which played a role in the creation of the Unix operating system; and "Baseball", an early sports game and the first baseball game to allow player control during a game. | https://en.wikipedia.org/wiki?curid=49386138 | 1,123,762 |
1,700,410 | Approximately 10 million proton-antiproton collisions happened every second in the detector. Because this far exceeded computing capabilities, only a fraction of these events could be stored on tape per second. Therefore, an intricate Data Acquisition (DAQ) system was implemented that determined which events were "interesting" enough to be written to tape and which could be thrown out. The trigger system used the electronic signals to identify events of interest, such as those containing electrons, muons, photons, high energy jets, or particles that traveled some distance before decaying. The first trigger level used the fast electronic signals from each subdetector to decide within a few microseconds whether to pause data-taking and digitize the signals. About 10,000 such Level 1 triggers were accepted. A second trigger level refined the selection using the digitized signals from several subdetectors in combination to form a more nuanced event profile, reducing the candidate event pool to 1000 events per second. In the third level, a farm of computers analyzed the digital information in a stripped-down version of the full offline computer code to yield up to 100 events per second to be permanently recorded and subsequently analyzed on large offline computer farms. The operation of the trigger system was a delicate balance between maximizing the number of events saved and minimizing the dead time incurred while collecting them. It had to be robust and reliable, as the millions of events not selected by the trigger were lost forever. | https://en.wikipedia.org/wiki?curid=3091589 | 1,699,456 |
664,614 | Freud's early publications on the symptoms of hysteria (with his influential concept of unconscious emotional conflict) acknowledged debts to Darwin's work on emotional expression and Darwin's impact on psychoanalysis is discussed in detail by Lucille Ritvo. John Bowlby makes extensive reference to Darwin's ideas in his presentations of attachment theory. Constitutional (psychosomatic) theories of personality were elaborated by neurologist Paul Schilder (1886–1940) with his notion of the body image, by the psychiatrist Ernst Kretschmer and in the (now largely discredited) somato-typology of W H Sheldon (1898–1977). The biological aspects of the human emotions were further explored by Desmond Morris in his (richly illustrated) popular scientific book "Manwatching", and recent research has confirmed that while cultural factors are critical in the determination of gesture, genetic factors are crucial to the formation of facial expression. In 2003, the New York Academy of Sciences published "Emotions Inside Out: 130 Years after Darwin's The Expression of the Emotions in Man and Animals", a collection of 37 papers (edited by Paul Ekman) with recent research on the subject. | https://en.wikipedia.org/wiki?curid=1704268 | 664,267 |
1,922,601 | Beyond their extracellular contact with each other, neurexins and neuroligins also bind intracellularly to a vast network of adaptor proteins and scaffolding structures, which in concert with the actin cytoskeleton, help localize necessary components of synaptic transmission. For example, the first neuroligin (NLGN1) discovered was identified by its PDZ domain which binds to PSD95, a well-known a scaffold protein at glutamatergic synapses that functionally links NMDA receptors to the proper post-synaptic locale. Similarly, another isoform of neuroligin (NLGN2) interacts with gephyrin, a scaffolding protein specific to GABA-ergic synapses, and is responsible for activation of the synaptic adapator protein collybistin. In the case of neurexins, their intracellular binding interactions are equally as important in recruiting the essential machinery for synaptic transmission at the active zone. Like neuroligins, neurexins possess a PDZ-domain that associates with CASK (Calcium-calmodulin-dependent protein kinase). In addition to phosphorylating itself and neurexin, CASK promotes interactions between neurexins and actin binding proteins, thus providing a direct link by which neurexin can modulate cytoskeletal dynamics that is essential for synaptic stability and plasticity. Neurexin can also bind synaptotagmin, a protein embedded in the membrane of synaptic vesicles, and can also promote associations with voltage-gated calcium channel which mediate the ion flux required for neurotransmitter exocytosis upon synaptic stimulation. In this way, neurexin and neuroligin coordinate the morphological and functional aspects of the synapse which in turn permits nascent, immature contacts to stabilize into full-fledged functional platforms for neurotransmission. | https://en.wikipedia.org/wiki?curid=56806820 | 1,921,498 |
1,109,827 | The evidence supporting the importance of the H/ACA domain in human telomerase is abundant. At least one study has shown that these mutations affect telomerase activity by negatively affecting pre-RNP assembly and maturation of human telomerase RNA. Nonetheless, mutations that directly affect the telomerase RNA components would presumably exist and should also cause premature aging or DKC-like symptoms. Indeed, three families with mutations in the human TERC gene have been studied with intriguing results. In two of these families, two family-specific single nucleotide polymorphisms were present while in the other there persisted a large-scale deletion (821 base pairs of DNA) on chromosome 3 which includes 74 bases coding for a section of the H/ACA domain. These three different mutations result in a mild form of dyskeratosis congenita which uniquely follows an autosomal dominant pattern of inheritance. Premature graying, early dental loss, predisposition to skin cancer, as well as shortening of telomere length continue to be characteristic of this disease. | https://en.wikipedia.org/wiki?curid=3076958 | 1,109,262 |
1,441,725 | One 3D printer in use in 2021 (Solidscape) still has a Howtek style nozzle as it was manufactured in 1986. It originally had a hex-shaped metal nozzle-end structure with an offset-nozzle orifice that allowed the jet drops to be (aimed) directed toward a target to align properly for the best print quality when it was previously installed in the Howtek Pixelmaster. Over 1500 Howtek style inkjets were acquired by early Sanders Prototype, Inc when production of the Modelmaker 6 Pro was first started in 1994. The Modelmaker 6 pro uses two inkjets per machine. The inkjets are installed in a special printhead directing the drops straight downward for 3D printing. The original prototype 3D printer, the Sculptor by Visual Impact Corporation, using Howtek nozzles, printed horizontally in 1989. The Pixelmaster also projected the drops horizontally from a 121 rpm rotating printhead to print 2D characters or images on paper. A Braille character printer was introduced by Howtek and only sold a few machines in 1990–1991 with raised-font printed on plain paper using Howtek inkjets. This required four layers of drops to stack up for each Braille character. This was an early example of how three-dimensional (ink) material printing (not called 3D printing in 1984) got started and now-a-days Additive Manufacturing (AM) does not reference historical jetting of hot-melt material properties used in 3D printing. 3D printing (printing with raised surface inks) was inkjet printing in the 1960–1980s with wax, liquid metal and thermoplastic hot-melt fluids. | https://en.wikipedia.org/wiki?curid=46964830 | 1,440,912 |
676,287 | The cytoplasmic polyhedrosis viruses (CPVs) form the genus Cypovirus of the family "Reoviridae". CPVs are classified into 14 species based on the electrophoretic migration profiles of their genome segments. Cypovirus has only a single capsid shell, which is similar to the orthoreovirus inner core. CPV exhibits striking capsid stability and is fully capable of endogenous RNA transcription and processing. The overall folds of CPV proteins are similar to those of other reoviruses. However, CPV proteins have insertional domains and unique structures that contribute to their extensive intermolecular interactions. The CPV turret protein contains two methylase domains with a highly conserved helix-pair/β-sheet/helix-pair sandwich fold but lacks the β-barrel flap present in orthoreovirus λ2. The stacking of turret protein functional domains and the presence of constrictions and A spikes along the mRNA release pathway indicate a mechanism that uses pores and channels to regulate the highly coordinated steps of RNA transcription, processing, and release. | https://en.wikipedia.org/wiki?curid=14346042 | 675,934 |
1,092,882 | The concept of theological determinism has its origins within the Bible as well as within Christianity. A major theological dispute at the time of the sixteenth century would help to force a distinct division in ideas - with an argument between two eminent thinkers of the time, Desiderius Erasmus and Martin Luther, a leading Protestant Reformer. Erasmus in "Discourses On the Freedom of the Will" believed that God created human beings with free will. He maintained that despite the fall of Adam and Eve freedom still existed. As a result of this humans had the ability to do good or evil. Luther, conversely, attacked this idea in "On the Bondage of the Will". He recognised that the issue of autonomy lay at the heart of religious dissension. He depicted an image of humanity manipulated through sin. Humans, for Luther, know what is morally right but are unable to attain it. He claimed that humans thus must give up aspiring to do good in their fallen state and by their own power, as only by this could salvation be formed. This is reflected in the reformation doctrine of Sola Fide, that asserts that salvation is by faith alone and not achieved by meritorious good works. Luther also believed that the fall of Adam and Eve as written in the Bible supported this notion. | https://en.wikipedia.org/wiki?curid=3176391 | 1,092,322 |
134,920 | In 2004, Sinclair, along with serial entrepreneur Andrew Perlman, Christoph Westphal, Richard Aldrich, Richard Pops, and Paul Schimmel, founded Sirtris Pharmaceuticals. Sirtris was focused on developing Sinclair's research into activators of sirtuins, work that began in the Guarente lab. The company was specifically focused on resveratrol formulations and derivatives as activators of the SIRT1 enzyme; Sinclair became known for making statements about resveratrol like: "(It's) as close to a miraculous molecule as you can find. ... One hundred years from now, people may be taking these molecules on a daily basis to prevent heart disease, stroke, and cancer." Most of the anti-aging field was more cautious, especially with regard to what else resveratrol might do in the body and its lack of bioavailability. The company's initial product was called SRT501, and was a formulation of resveratrol. Sirtris went public in 2007 and was subsequently purchased and made a subsidiary of GlaxoSmithKline in 2008 for $720 million. Five years later, GSK shuttered the Sirtris program without successful drug development. | https://en.wikipedia.org/wiki?curid=7804853 | 134,865 |
1,991,633 | California State University, Long Beach reported on April 29 that a student had returned a "probable positive" test result for swine influenza. The student showed symptoms on Sunday April 26 and went to the campus health services office the following day. The test results were received by the school on April 28 and distributed to all students and faculty. The affected student had not attended any classes since falling ill and has an apparently mild case of the disease that does not appear life-threatening. Three high schools in Riverside County were closed April 29 after two teenage girls, from Corona and Indio respectively, were confirmed to have contracted the virus. Branham High School in San Jose was closed that day for a week after one teenage girl was confirmed to be a probable case. Rucker Elementary School in Gilroy is set to be closed on Friday, May 1 after at least one student was being tested after exhibiting flu-like symptoms. Three students at the Grizzly Youth Academy in San Luis Obispo are confirmed cases of swine influenza. As many as 73 students are exhibiting flu-like symptoms at The academy and are assumed to have the virus. All are being isolated. The academy is set to stay open. On May 3, 2009, parent of students attending King Middle School in Berkeley were notified that their school would be closed down due to a swine flu outbreak involving students at the school. Days later, other schools were closed down because of students or staff exhibiting flu-like symptoms; for example, Sunnyside Elementary School and Woodville Elementary School, both in Tulare County. | https://en.wikipedia.org/wiki?curid=23392449 | 1,990,490 |
1,165,333 | Recent versions of the GNU Compiler Collection (GCC), IBM VisualAge compiler and other compilers provide intrinsics to access VMX/AltiVec instructions directly from C and C++ programs. As of version 4, the GCC also includes auto-vectorization capabilities that attempt to intelligently create VMX/Altivec accelerated binaries without the need for the programmer to use intrinsics directly. The "vector" type keyword is introduced to permit the declaration of native vector types, e.g., "codice_1" declares a 128-bit vector variable named "foo" containing sixteen 8-bit unsigned chars. The full complement of arithmetic and binary operators is defined on vector types so that the normal C expression language can be used to manipulate vector variables. There are also overloaded intrinsic functions such as "codice_2" that emit the appropriate opcode based on the type of the elements within the vector, and very strong type checking is enforced. In contrast, the Intel-defined data types for IA-32 SIMD registers declare only the size of the vector register (128 or 64 bits) and in the case of a 128-bit register, whether it contains integers or floating-point values. The programmer must select the appropriate intrinsic for the data types in use, e.g., "codice_3" for adding two vectors containing eight 16-bit integers. | https://en.wikipedia.org/wiki?curid=55360 | 1,164,716 |
366,023 | The gene MKRN3, which is a maternally imprinted gene, was first cloned by Jong et al. in 1999. MKRN3 was originally named Zinc finger protein 127. It is located on human chromosome 15 on the long arm in the Prader-Willi syndrome critical region2, and has since been identified as a cause of premature sexual development or CPP. The identification of mutations in MKRN3 leading to sporadic cases of CPP has been a significant contribution to better understanding the mechanism of puberty. MKRN3 appears to act as a "brake" on the central hypothalamic-pituitary access. Thus, loss of function mutations of the protein allow early activation of the GnRH pathway and cause phenotypic CPP. Patients with a MKRN3 mutation all display the classic signs of CCP including early breast and testes development, increased bone aging and elevated hormone levels of GnRH and LH. | https://en.wikipedia.org/wiki?curid=651370 | 365,832 |
865,778 | Point-of-care tests are simple medical tests that can be performed at the bedside. In many cases, the simplicity was not achievable until technology developed not only to make a test possible at all but then also to mask its complexity. For example, various kinds of urine test strips have been available for decades, but portable ultrasonography did not reach the stage of being advanced, affordable, and widespread until the 2000s and 2010s. Today, portable ultrasonography is often viewed as a "simple" test, but there was nothing simple about it until the more complex technology was available. Similarly, pulse oximetry can test arterial oxygen saturation in a quick, simple, noninvasive, affordable way today, but in earlier eras this required an intra-arterial needle puncture and a laboratory test; and rapid diagnostic tests such as malaria antigen detection tests or COVID-19 rapid tests that rely on a state of the art in immunology that did not exist until recent decades. Thus, over decades, testing continues to move toward the point of care more than it formerly had been. A recent survey in five countries (Australia, Belgium, the Netherlands, the UK and the US) indicates that general practitioners / family doctors would like to use more POCTs. | https://en.wikipedia.org/wiki?curid=8713563 | 865,318 |
1,645 | By 1947, US president Harry S. Truman was outraged by the perceived resistance of the Soviet Union to American demands in Iran, Turkey, and Greece, as well as Soviet rejection of the Baruch Plan on nuclear weapons. In February 1947, the British government announced that it could no longer afford to finance the Kingdom of Greece in its civil war against Communist-led insurgents. In the same month, Stalin conducted the rigged 1947 Polish legislative election which constituted an open breach of the Yalta Agreement. The US government responded to this announcement by adopting a policy of containment, with the goal of stopping the spread of communism. Truman delivered a speech calling for the allocation of $400 million to intervene in the war and unveiled the Truman Doctrine, which framed the conflict as a contest between free peoples and totalitarian regimes. American policymakers accused the Soviet Union of conspiring against the Greek royalists in an effort to expand Soviet influence even though Stalin had told the Communist Party to cooperate with the British-backed government. (The insurgents were helped by Josip Broz Tito's Socialist Federal Republic of Yugoslavia against Stalin's wishes.) | https://en.wikipedia.org/wiki?curid=325329 | 1,645 |
2,074,715 | As in land-based commerce, digital data sharing is a growing phenomenon in maritime operations - though there is a way to go. It is enabling greater transparency for all those involved in the transportation of goods and passengers, not least being the end-customer. This leads to better and more informed decision-making and planning by all those involved. The push for digitalisation and data sharing is being pursued both by governments and the commercial sector. For example, the Member States of the IMO agreed a mandatory requirement for their governments to introduce electronic information exchange between ships and ports as from 8 April 2019. Meanwhile, commercial operators, particularly in the container lines are putting systems in place for sharing data for mutual benefit in their operations. Data sharing is an important aspect of the Port Collaborative Decision Making (PortCDM) and Port Call Optimization initiatives, both of which seek to improve the coordination, synchronization and efficiency of the port call process by enabling a common and shared situational awareness among all those involved. | https://en.wikipedia.org/wiki?curid=66555983 | 2,073,519 |
1,259,207 | AOSLO compares favorably with other retinal imaging techniques as well. Fluorescein angiography uses injection of a fluorescein dye to image the back of the retina. It is a commonly used technique but it has a large number of side effects, including nausea in one fifth of patients and in some cases death from anaphylaxis. Optical coherence tomography (OCT) represents a powerful clinical tool for monitoring retinal physiology in patients. OCT uses low coherence interferometry to differentiate tissues within the eye and create a cross section of a living patients’ retina non-invasively. It actually has greater axial resolution than AOSLO. However, AOSLO represents a method with much greater translational resolution than OCT and can thus be used to track minor lateral physical changes such as the effects of eye movements on the retina. A combination of AOSLO and OCT has recently been attempted in one apparatus to produce the first three-dimensional images of individual cone cells and illustrate the overall cone mosaic near the fovea at high speeds. | https://en.wikipedia.org/wiki?curid=660008 | 1,258,520 |
1,952,837 | Problems associated with the design of the axial piston engine include high oil consumption, high fuel consumption, low rpm limit imposed by previously discussed frictional loads, low overall horsepower, mechanical complexity and complex machining methods needs to allow the engine to stand up to the loads imposed on the components. Additional problems are noted in that, the design does not have a long lifespan when compared to other engine designs due to large numbers of moving parts and relative high stresses. Wear and tear occurs at a faster rate because the engine makes more power pulses per turn of the cam than traditional engines. Lastly, due to very high initial torque and a need for large amounts of coolant, loss of oil or coolant to this design during running will almost certainly result in a catastrophic explosion of the engine because the engine generally has very light casings or shields located in the area around the cams and connecting rods. | https://en.wikipedia.org/wiki?curid=13273827 | 1,951,716 |
1,929,534 | In the 19th century it was common to use a metal screen in front of a window on a North facing wall. However, the building may warm the screen leading to higher temperature measurements. When this problem was realized the Stevenson screen was introduced, typically installed in gardens, away from buildings. This is still the most typical weather screen with its characteristic double-louvre door and walls for ventilation. The historical Montsouri and Wilds screens were used around 1900 and are open to the North and to the bottom. This improves ventilation, but it was found that infra-red radiation from the ground can influence the measurement on sunny calm days. Therefore, they are no longer used. Nowadays automatic weather stations, which reduce labor costs, are becoming more common; they protect the thermometer by a number of white plastic cones. This necessitated changes from manually recorded liquid and glass thermometers to automated electrical resistance thermometers, which reduced the recorded temperature values in the USA. | https://en.wikipedia.org/wiki?curid=34740535 | 1,928,428 |
1,152,726 | After a brief return to Cambridge, Grant applied for the vacant chair of Humanity (Latin) at Edinburgh University which he held from 1948 until 1959. During a two-year (1956–58) leave of absence he also served as vice-chancellor (president) of the University of Khartoum – upon his departure, he turned the university over to the newly independent Sudanese government. He was then vice-chancellor of Queen's University of Belfast (1959–66), after which he pursued a career as a full-time writer. According to his obituary in "The Times" he was "one of the few classical historians to win respect from [both] academics and a lay readership". Immensely prolific, he wrote and edited more than 70 books of nonfiction and translation, covering topics from Roman coinage and the eruption of Mount Vesuvius to the Gospels. He produced general surveys of ancient Greek, Roman and Israelite history as well as biographies of giants such as Julius Caesar, Herod the Great, Cleopatra, Nero, Jesus, St. Peter and St. Paul. | https://en.wikipedia.org/wiki?curid=1458399 | 1,152,116 |
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