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983,244 | The Hadza people of Tanzania also share food, possibly to gain in reputation. Hunters cannot be sharing meat mainly to provision their families or to gain reciprocal benefits, as teenage boys often give away their meat even though they do not yet have wives or children, so costly signalling of their qualities is the likely explanation. These qualities include good eyesight, coordination, strength, knowledge, endurance, or bravery. Hadza hunters more often pair with highly fertile, hard-working wives than non-hunters. A woman benefits from mating with a man who possesses such qualities as her children will most likely inherit qualities that increase fitness and survivorship. She may also benefit from her husband's high social status. Thus, hunting is an honest and costly signal of phenotypic quality. Frank W. Marlowe’s "The Hadza: Hunter-Gatherers of Tanzania" showed that this data confirms that this is also true within the Hazda, based on the documentation on the !Kung, in Megan Biesele’s book about !Kung folklore called Women Like Meat. | https://en.wikipedia.org/wiki?curid=1318175 | 982,730 |
715,090 | The 003 was selected as the basis for a gas turbine development project for the German military's anticipated need for what is today called a turboshaft powerplant for multiple needs — this project was called the GT 101, using the 003 axial-flow turbojet as the starting point in mid-November 1944. Its original purpose would have been to re-engine the Panther tank with a turboshaft-based power system capable of up to a 1,150 PS usable shaft horsepower rating into an AFV's drivetrain, from an engine weight of only , giving it a 27 hp/ton power-to-weight ratio — just over twice the factor that the Panther's original gasoline-fueled Maybach V12 piston engine provided. | https://en.wikipedia.org/wiki?curid=408868 | 714,716 |
199,519 | In 1906, Sven Wingquist patented the self-aligning ball bearings and in 1907 – the multi-row self-regulating radial ball bearing (spherical ball bearing). He graduated Orebro Technical Elementary School in 1894, whereafter he started working as an engineer in Swedish textile factories, respectively Jonsereds Fabriker from 1896 to 1899 and Gamlestadens Fabriker AD from 1899 onwards. As an operations engineer responsible for repairs and maintenance at Gamlestadens Fabriker AD he sought opportunities to improve the efficiency and endurance of the ball bearings used at the time. Due to that, he was interested in a comparative study from 1902 about ball and plain bearings by professor Richard Stribeck of the Institute of Technology in Dresden, Germany. Sven Wingquist invented the first design of combined self-aligning spherical ball bearing. It was a revolutionary upgrade of the first ball bearing design which was invented and patented by British iron-maker Philip Vaughan in 1794 and the first design of self-aligning spherical plain bearing which was invented by Scottish engineer James Nasmyth around 1840. The historical development of bearing’s design is a result of revolutionary inventions and upgrades for improvement of their efficiency and endurance as well as broadening the scope of their application to a variety of machine industry sectors. | https://en.wikipedia.org/wiki?curid=89744 | 199,416 |
551,768 | Structural proteins that bind DNA are well-understood examples of non-specific DNA-protein interactions. Within chromosomes, DNA is held in complexes with structural proteins. These proteins organize the DNA into a compact structure called chromatin. In eukaryotes, this structure involves DNA binding to a complex of small basic proteins called histones. In prokaryotes, multiple types of proteins are involved. The histones form a disk-shaped complex called a nucleosome, which contains two complete turns of double-stranded DNA wrapped around its surface. These non-specific interactions are formed through basic residues in the histones making ionic bonds to the acidic sugar-phosphate backbone of the DNA, and are therefore largely independent of the base sequence. Chemical modifications of these basic amino acid residues include methylation, phosphorylation and acetylation. These chemical changes alter the strength of the interaction between the DNA and the histones, making the DNA more or less accessible to transcription factors and changing the rate of transcription. Other non-specific DNA-binding proteins in chromatin include the high-mobility group (HMG) proteins, which bind to bent or distorted DNA. Biophysical studies show that these architectural HMG proteins bind, bend and loop DNA to perform its biological functions. These proteins are important in bending arrays of nucleosomes and arranging them into the larger structures that form chromosomes. Recently FK506 binding protein 25 (FBP25) was also shown to non-specifically bind to DNA which helps in DNA repair. | https://en.wikipedia.org/wiki?curid=966654 | 551,480 |
1,415,262 | In the 1970s, "Dunaliella" dominated the north arm planktonic community, since the waters were too salty for other algae to thrive. The organisms were horizontally and rather randomly distributed on the surface, especially in places with minimal sunlight such as underneath rocks and logs. They were found in densities of 200–1000 cells/ml and sometimes in peak densities of 3000–10000 cells/ml. At times they were even found to be more abundant at deeper depths, though little is known on whether this was due to intolerable light intensities at the surface. Even in the less saline south arm, "Dunaliella" was responsible for various short-lived blooms with up to 25000 cells/ml. Unfortunately, populations in both arms went into decline after periods of increased precipitations that decreased the Great Salt Lake's salinity. Dunaliella started to become outcompeted by other phototrophs like the cyanobacterium "Nodularia". | https://en.wikipedia.org/wiki?curid=13116468 | 1,414,465 |
1,988,833 | ALR was one of the first companies to license the Micro Channel architecture from IBM in 1988. The MicroFlex 7000, released in January 1989 and configured with a 25-MHz i386 and 16 MB of SIMM random-access memory, was billed as outpacing IBM's MCA-based PS/2 Model 70 due to the inclusion of a proprietary cache prefetching system in its chipset. The company's i386-based FlexCache 25386 earned the company a "PC Magazine" Award for Technical Excellence for desktop computers in 1988. Year-to-year sales from September 1988 totaled $40 million—one-tenth of AST's but up from $5 million in 1986—prompting Lu negotiate buying out Wearnes Brothers' stake in the company. The buyout was completed in December 1988 for an undisclosed sum. ALR later ditched Micro Channel for the directly competing Extended Industry Standard Architecture in October 1989, releasing the PowerCache/4e later that year. | https://en.wikipedia.org/wiki?curid=69737291 | 1,987,691 |
759,212 | The first criticism concerns the origin of the impact melt rocks that were sampled at the Apollo landing sites. While these impact melts have been commonly attributed to having been derived from the closest basin, it has been argued that a large portion of these might instead be derived from the Imbrium basin. The Imbrium impact basin is the youngest and largest of the multi-ring basins found on the central nearside of the Moon, and quantitative modeling shows that significant amounts of ejecta from this event should be present at all of the Apollo landing sites. According to this alternative hypothesis, the cluster of impact melt ages near 3.9 Ga simply reflects material being collected from a single impact event, Imbrium, and not several. Additional criticism also argues that the age spike at 3.9 Ga identified in Ar/Ar dating could also be produced by an episodic early crust formation followed by partial Ar losses as the impact rate declined. | https://en.wikipedia.org/wiki?curid=30864636 | 758,806 |
13,864 | Continuing improvements led to the furnace and bellows and provided, for the first time, the ability to smelt and forge gold, copper, silver, and lead native metals found in relatively pure form in nature. The advantages of copper tools over stone, bone and wooden tools were quickly apparent to early humans, and native copper was probably used from near the beginning of Neolithic times (about 10 ka). Native copper does not naturally occur in large amounts, but copper ores are quite common and some of them produce metal easily when burned in wood or charcoal fires. Eventually, the working of metals led to the discovery of alloys such as bronze and brass (about 4,000 BCE). The first use of iron alloys such as steel dates to around 1,800 BCE. | https://en.wikipedia.org/wiki?curid=29816 | 13,859 |
1,086,650 | A cannabinoid receptor antagonist, also known simply as a cannabinoid antagonist or as an anticannabinoid, is a type of cannabinoidergic drug that binds to cannabinoid receptors (CBR) and prevents their activation by endocannabinoids. They include antagonists, inverse agonists, and antibodies of CBRs. The discovery of the endocannabinoid system led to the development of CB receptor antagonists. The first CBR inverse agonist, rimonabant, was described in 1994. Rimonabant blocks the CB receptor selectively and has been shown to decrease food intake and regulate body-weight gain. The prevalence of obesity worldwide is increasing dramatically and has a great impact on public health. The lack of efficient and well-tolerated drugs to cure obesity has led to an increased interest in research and development of CBR antagonists. Cannabidiol (CBD), a naturally occurring cannabinoid, is a non-competitive CB/CB receptor antagonist. And Δ-tetrahydrocannabivarin (THCV), a naturally occurring cannabinoid, modulate the effects of THC via direct blockade of cannabinoid CB receptors, thus behaving like first-generation CB receptor inverse agonists, such as rimonabant. CBD is a very low-affinity CB ligand, that can nevertheless affect CB receptor activity "in vivo" in an indirect manner, while THCV is a high-affinity CB receptor ligand and potent antagonist "in vitro" and yet only occasionally produces effects "in vivo" resulting from CB receptor antagonism. THCV has also high affinity for CB receptors and signals as a partial agonist, differing from both CBD and rimonabant. | https://en.wikipedia.org/wiki?curid=20207596 | 1,086,092 |
1,954,372 | Berkelium forms a number of chemical compounds, where it normally exists in an oxidation state of +3 or +4, and behaves similarly to its lanthanide analogue, terbium. Like all actinides, berkelium easily dissolves in various aqueous inorganic acids, liberating gaseous hydrogen and converting into the trivalent oxidation state. This trivalent state is the most stable, especially in aqueous solutions, but tetravalent berkelium compounds are also known. The existence of divalent berkelium salts is uncertain and has only been reported in mixed lanthanum chloride-strontium chloride melts. Aqueous solutions of Bk ions are green in most acids. The color of the Bk ions is yellow in hydrochloric acid and orange-yellow in sulfuric acid. Berkelium does not react rapidly with oxygen at room temperature, possibly due to the formation of a protective oxide surface layer; however, it reacts with molten metals, hydrogen, halogens, chalcogens and pnictogens to form various binary compounds. Berkelium can also form several organometallic compounds. | https://en.wikipedia.org/wiki?curid=31422050 | 1,953,250 |
1,062,058 | The chosen solid surface is then covered with a coating that must serve the simultaneous functions of immobilising the protein, preventing its denaturation, orienting it in the appropriate direction so that its binding sites are accessible, and providing a hydrophilic environment in which the binding reaction can occur. It also needs to display minimal non-specific binding in order to minimize background noise in the detection systems. Furthermore, it needs to be compatible with different detection systems. Immobilising agents include layers of aluminium or gold, hydrophilic polymers, and polyacrylamide gels, or treatment with amines, aldehyde or epoxy. Thin-film technologies like physical vapour deposition (PVD) and chemical vapour deposition (CVD) are employed to apply the coating to the support surface. | https://en.wikipedia.org/wiki?curid=1659679 | 1,061,504 |
694,533 | Urey and Washburn attempted to use electrolysis to create pure heavy water. Their technique was sound, but they were beaten to it in 1933 by Lewis, who had the resources of the University of California at his disposal. Using the Born–Oppenheimer approximation, Urey and David Rittenberg calculated the properties of gases containing hydrogen and deuterium. They extended this to enriching compounds of carbon, nitrogen, and oxygen. These could be used as tracers in biochemistry, resulting in a whole new way of examining chemical reactions. He founded the Journal of Chemical Physics in 1932, and was its first editor, serving in that capacity until 1940. | https://en.wikipedia.org/wiki?curid=453578 | 694,170 |
1,382,196 | A MALS measurement requires a set of ancillary elements. Most important among them is a collimated or focused light beam (usually from a laser source producing a collimated beam of monochromatic light) that illuminates a region of the sample. In modern instruments, the beam is generally plane-polarized perpendicular to the plane of measurement, though other polarizations may be used especially when studying anisotropic particles. Earlier measurements, before the introduction of lasers, were performed using focused, though unpolarized, light beams from sources such as Hg-arc lamps. Another required element is an optical cell to hold the sample being measured. Alternatively, cells incorporating means to permit measurement of flowing samples may be employed. If single-particles scattering properties are to be measured, a means to introduce such particles one-at-a-time through the light beam at a point generally equidistant from the surrounding detectors must be provided. | https://en.wikipedia.org/wiki?curid=23959374 | 1,381,433 |
1,956,635 | In 2004, a prolonged drought affected the Chaco Region, which consists of the Departments of Santa Cruz, Chuquisaca and Tarija, threatened the food security, health and nutritional status of approximately 180,000 people, of which 15 percent were children. El Niño 2006/2007 event caused economic losses estimated at US$0.44 billion or 4 percent of gross domestic product (GDP) and affected about 133,100 families or 0.56 million people, equivalent to five times the population affected by El Niño 1997/1998. About 54 percent of the losses occurred in the rural areas. La Niña 2007/2008 event caused damage and losses evaluated at US$0.52 billion, 20 percent higher than the previous event and affected about 123,600 families. The agricultural sector absorbed about 53 percent of these losses and damage. | https://en.wikipedia.org/wiki?curid=18250180 | 1,955,511 |
474,674 | A detailed optical calibration model was included to map the transformation from sky to instrumental coordinates. Its adequacy could be verified by the detailed measurement residuals. The Earth's orbit, and the satellite's orbit with respect to the Earth, were essential for describing the location of the observer at each epoch of observation, and were supplied by an appropriate Earth ephemeris combined with accurate satellite ranging. Corrections due to special relativity (stellar aberration) made use of the corresponding satellite velocity. Modifications due to general relativistic light bending were significant (4 milliarc-sec at 90° to the ecliptic) and corrected for deterministically assuming γ=1 in the PPN formalism. Residuals were examined to establish limits on any deviations from this general relativistic value, and no significant discrepancies were found. | https://en.wikipedia.org/wiki?curid=207964 | 474,438 |
71,307 | The alkaline fuel cell (AFC) or hydrogen-oxygen fuel cell was designed and first demonstrated publicly by Francis Thomas Bacon in 1959. It was used as a primary source of electrical energy in the Apollo space program. The cell consists of two porous carbon electrodes impregnated with a suitable catalyst such as Pt, Ag, CoO, etc. The space between the two electrodes is filled with a concentrated solution of KOH or NaOH which serves as an electrolyte. H gas and O gas are bubbled into the electrolyte through the porous carbon electrodes. Thus the overall reaction involves the combination of hydrogen gas and oxygen gas to form water. The cell runs continuously until the reactant's supply is exhausted. This type of cell operates efficiently in the temperature range 343–413K and provides a potential of about 0.9V. Alkaline anion exchange membrane fuel cell (AAEMFC) is a type of AFC which employs a solid polymer electrolyte instead of aqueous potassium hydroxide (KOH) and it is superior to aqueous AFC. | https://en.wikipedia.org/wiki?curid=11729 | 71,280 |
1,069,062 | Increasingly organic compounds are being found on objects throughout the Solar System. While unlikely to indicate the presence of extraterrestrial life, all known life is based on these compounds. Complex carbon molecules may form through various complex chemical interactions or delivered through impacts with small solar system objects and can combine to form the "building blocks" of Carbon-based life. As organic compounds are often volatile, their persistence as a solid or liquid on a planetary surface is of scientific interest as it would indicate an intrinsic source (such as from the object's interior) or residue from larger quantities of organic material preserved through special circumstances over geological timescales, or an extrinsic source (such as from past or recent collision with other objects). Radiation makes the detection of organic matter difficult, making its detection on atmosphereless objects closer to the Sun extremely difficult. | https://en.wikipedia.org/wiki?curid=34661457 | 1,068,508 |
333,512 | The AWM in the .338 Lapua Magnum (8.6×70mm) calibre was designed as a dedicated long range sniper rifle. The rifle is fitted with a stainless steel, fluted, barrel, which research has found to be the best compromise between muzzle velocity, weight, and length. The barrel has an unconventional 279 mm (1:11 in) right-hand twist rate, optimized for firing .338-calibre very-low-drag bullets up to 16.85 g (260 gr). When the AWM .338 Lapua Magnum was developed military issue cartridges were loaded with 16.2 g (250 gr) very-low-drag bullets. Longer, heavier very-low-drag bullets like the Sierra HPBT MatchKing .338-calibre 19.44 g (300 gr) and the 21st century 19.44 gram (300 grain) .338-calibre HPBT Scenar can be used, but require a 254 mm (1:10 in) twist rate to stabilize them under high air density conditions as found on arctic coasts. | https://en.wikipedia.org/wiki?curid=737919 | 333,334 |
1,020,784 | Digital clocks and Internet gaming have spurred a wave of experimentation with more varied and complex time controls than the traditional standards. Time control is commonly used in modern chess in many different methodologies. One particularly notable development, which has gained quite wide acceptance in chess, was proposed by former world champion Bobby Fischer, who in 1988 filed for US patent 4,884,255 (awarded in 1989) for a new type of digital chess clock. Fischer's digital clock gave each player a fixed period of time at the start of the game and then added a small amount after each move. Joseph Meshi called this "Accumulation" as it was a main feature of his patented Micromate-180 (US Patent 4,247,925 1978). This became the linchpin of Fischer's clock patented ten years later. In this way, the players would never be desperately short of time. This timing method is occasionally called "accumulation" but it is usually called "increment", "bonus", or "Fischer". | https://en.wikipedia.org/wiki?curid=47653 | 1,020,255 |
238,318 | Technetium plays no natural biological role and is not normally found in the human body. Technetium is produced in quantity by nuclear fission, and spreads more readily than many radionuclides. It appears to have low chemical toxicity. For example, no significant change in blood formula, body and organ weights, and food consumption could be detected for rats which ingested up to 15 µg of technetium-99 per gram of food for several weeks. In the body, technetium quickly gets converted to the stable ion, which is highly water-soluble and quickly excreted. The radiological toxicity of technetium (per unit of mass) is a function of compound, type of radiation for the isotope in question, and the isotope's half-life. | https://en.wikipedia.org/wiki?curid=30041 | 238,198 |
133,304 | Geology did not undergo systematic restructuring during the Scientific Revolution but instead existed as a cloud of isolated, disconnected ideas about rocks, minerals, and landforms long before it became a coherent science. Robert Hooke formulated a theory of earthquakes, and Nicholas Steno developed the theory of superposition and argued that fossils were the remains of once-living creatures. Beginning with Thomas Burnet's "Sacred Theory of the Earth" in 1681, natural philosophers began to explore the idea that the Earth had changed over time. Burnet and his contemporaries interpreted Earth's past in terms of events described in the Bible, but their work laid the intellectual foundations for secular interpretations of Earth history. | https://en.wikipedia.org/wiki?curid=14400 | 133,251 |
2,230,305 | A graduate of St. Francis College of Pennsylvania, where he had played basketball, forward Fred Fees enrolled in Georgetown University Law School and joined the team – permitted despite his undergraduate playing time under the eligibility rules of the era – for the first of four seasons with the Hoyas. A free-throw shooting specialist in an era when the rules of college basketball allowed teams to choose which player shot its free throws, Fees exploited his free-throw prowess to establish himself as one of the top scorers in college basketball in the United States in each of his seasons with the Hoyas. This season he scored 195 of the teams 450 points, averaging 15.3 points per game to lead the team in scoring. He also shot 17-for-21 from the free-throw line in a game against George Washington, setting a school record for free throws made in a single game that no Hoya would exceed for 75 years. | https://en.wikipedia.org/wiki?curid=41681804 | 2,229,040 |
286,072 | In physical cosmology, the Big Rip is a hypothetical cosmological model concerning the ultimate fate of the universe, in which the matter of the universe, from stars and galaxies to atoms and subatomic particles, and even spacetime itself, is progressively torn apart by the expansion of the universe at a certain time in the future, until distances between particles will become infinite. According to the standard model of cosmology, the scale factor of the universe is accelerating, and, in the future era of cosmological constant dominance, will increase exponentially. However, this expansion is similar for every moment of time (hence the exponential law – the expansion of a local volume is the same number of times over the same time interval), and is characterized by an unchanging, small Hubble constant, effectively ignored by any bound material structures. By contrast, in the Big Rip scenario the Hubble constant increases to infinity in a finite time. | https://en.wikipedia.org/wiki?curid=192989 | 285,918 |
2,152,847 | At the end of 2020 Hayman said that it was still early days for the virus and while New Zealand had controlled the spread of the virus to that point, the country needed to be "patient and vigilant" and he looked forward to the increased uptake of the vaccines. As New Zealand moved from an elimination of the virus to a suppression approach, Hayman commented in October 2021 that this had not been totally effective in other countries and cited the United Kingdom which had high rates of infection and a strain on their health system. He said that COVID-19 was a vaccine-preventable disease, and the key was to get high rates of vaccination quickly to "stop transmission, stop people dying, but also manage the healthcare system." | https://en.wikipedia.org/wiki?curid=70083782 | 2,151,616 |
535,162 | The Australian military suffered a series of defeats during the early months of the Pacific War. The 8th Division and RAAF squadrons in Malaya formed a part of the British Commonwealth forces which were unable to stop a smaller Japanese invasion force which landed on 7 December. The British Commonwealth force withdrew to Singapore at the end of January, but was forced to surrender on 15 February after the Japanese captured much of the island. Smaller Australian forces were also overwhelmed and defeated during early 1942 at Rabaul, and in Ambon, Timor, and Java. The Australian town of Darwin was heavily bombed by the Japanese on 19 February, to prevent it from being used as an Allied base. Over 22,000 Australians were taken prisoner in early 1942 and endured harsh conditions in Japanese captivity. The prisoners were subjected to malnutrition, denied medical treatment and frequently beaten and killed by their guards. As a result, 8,296 Australian prisoners died in captivity. | https://en.wikipedia.org/wiki?curid=1323516 | 534,883 |
1,020,715 | Since 2005, the Genographic Project has used the latest genetic technology to expand our knowledge of the human story, and its pioneering use of DNA testing to engage and involve the public in the research effort has helped to create a new breed of "citizen scientist". Geno 2.0 expands the scope for citizen science, harnessing the power of the crowd to discover new details of human population history. This includes supporting, organization and dissemination of personal DNA (genetic) testing. Like amateur astronomy, citizen scientists encouraged by volunteer organizations like the International Society of Genetic Genealogy have provided valuable information and research to the professional scientific community. | https://en.wikipedia.org/wiki?curid=2155752 | 1,020,186 |
1,074,027 | It is of great importance to assign the NOESY peaks to the correct nuclei based on the chemical shifts. If this task is performed manually it is usually very labor-intensive, since proteins usually have thousands of NOESY peaks. Some computer programs such as PASD/XPLOR-NIH, UNIO, CYANA, ARIA/CNS, and AUDANA/PONDEROSA-C/S in the Integrative NMR platform perform this task automatically on manually pre-processed listings of peak positions and peak volumes, coupled to a structure calculation. Direct access to the raw NOESY data without the cumbersome need of iteratively refined peak lists is so far only granted by the PASD algorithm implemented in XPLOR-NIH, the ATNOS/CANDID approach implemented in the UNIO software package, and the PONDEROSA-C/S and thus indeed guarantees objective and efficient NOESY spectral analysis. | https://en.wikipedia.org/wiki?curid=3654507 | 1,073,473 |
898,157 | In 2003, "PNAS" issued an editorial stating its policy on publication of sensitive material in the life sciences. "PNAS" stated that it would "continue to monitor submitted papers for material that may be deemed inappropriate and that could, if published, compromise the public welfare." This statement was in keeping with the efforts of several other journals. In 2005 "PNAS" published an article titled "Analyzing a bioterror attack on the food supply: The case of botulinum toxin in milk", despite objections raised by the U.S. Department of Health and Human Services. The paper was published with a commentary by the president of the Academy at the time, Bruce Alberts, titled "Modeling attacks on the food supply". | https://en.wikipedia.org/wiki?curid=224259 | 897,683 |
1,484,824 | In 2000, Misawa, Kakihara and a large group of wrestlers left to form Pro Wrestling Noah, but he soon left the promotion because of a few personal problems with fellow wrestler Takao Omori. In his first and only match for NOAH, a six-man tag team match involving him, Yoshinari Ogawa and Daisuke Ikeda against Omori, Takayama and Satoru Asako on the promotion's first show, Kakihara appeared wearing mixed martial arts gloves and got in a scuffle with Omori, beating him down with stiff strikes. Immediately after Kakihara left, claiming he was interested in competing for Pride Fighting Championships like several of his fellow shoot-style wrestlers. However, he instead returned as a freelancer to AJPW, where the Noah exodus had left new chances. He joined another shoot-stylist, Mitsuya Nagai, and they won the vacant All Asia Tag Team Championship against Yuji Nagata and Shinya Makabe. Their reign would be short, as Masahito suffered a knee injury and was forced to vacate the titles again. He didn't return to AJPW when he recovered. | https://en.wikipedia.org/wiki?curid=33960859 | 1,483,987 |
390,913 | Besides the enthusiasm that developed in the Latin and Byzantine worlds in the Middle Ages for Pythagorean numerology, the Pythagorean tradition of perfect numbers inspired profound scholarship in mathematics. In the 13th century Leonardo of Pisa, better known as Fibonacci, published the "Libre quadratorum" ("The Book of Squares"). Fibonacci had studied scripts from Egypt, Syria, Greece and Sicily, and was learned in Hindu, Arabic and Greek methodologies. Using the Hindu–Arabic numeral system instead of the Roman numerals, he explored numerology as it had been set forth by Nicomachus. Fibonacci observed that square numbers always arise through the addition of consecutive odd numbers starting with unity. Fibonacci put forward a method of generating sets of three square numbers that satisfied the relationship first attributed to Pythagoras by Vitruvius, that . This equation is now known as the Pythagorean triple. | https://en.wikipedia.org/wiki?curid=291170 | 390,718 |
653,711 | Seafood Watch, one of the better-known sustainable seafood advisory lists, recommends consumers avoid eating anguillid eels due to significant pressures on worldwide populations. Several species used as "unagi" have seen their population sizes greatly reduced in the past half century. Catches of the European eel, for example, have declined about 80% since the 1960s. Although about 90% of freshwater eels consumed in the US are farm-raised, they are not bred in captivity. Instead, young eels are collected from the wild and then raised in various enclosures. In addition to wild eel populations being reduced by this process, eels are often farmed in open-net pens, which allow parasites, waste products, and diseases to flow directly back into wild eel habitat, further threatening wild populations. Freshwater eels are carnivores so are fed other wild-caught fish, adding another element of unsustainability to current eel-farming practices. | https://en.wikipedia.org/wiki?curid=2349109 | 653,367 |
1,174,085 | The Mukaiyama aldol reaction and the Sakurai reaction refer to the addition of silyl enol ethers and allylsilanes to carbonyl compounds, respectively. Only under Lewis acid catalysis do these reactions occur under synthetically useful conditions. Acyclic transition states are believed to be operating in both reactions for either 1,2- or 1,4- addition, and steric factors control stereoselectivity. This is in contrast with the rigid Zimmerman-Traxler cyclic transition state that has been widely accepted for the aldol reaction with lithium, boron, and titanium enolates. As a consequence, the double bond geometry in the silyl enol ether or allylsilane does not translate well into product stereochemistry. A model for the Sakurai 1,2-addition, proposed by Kumada, is presented in the scheme below; the "syn" diastereomer is predominant when the "(E)" silane is used, and also slightly favored when the "(Z)" silane is used. A similar analysis by Heathcock explains the fact that, with simple substrates, there is essentially no diastereoselectivity for the intermolecular Mukaiyama aldol reaction. | https://en.wikipedia.org/wiki?curid=37264695 | 1,173,463 |
164,392 | San Lorenzo Colossal Head 6 (also known as San Lorenzo Monument 17) is one of the smaller examples of colossal heads, standing . It measures wide by deep and is estimated to weigh between 8 and 10 tons. The head was discovered by a local farmworker and was excavated in 1965 by Luis Aveleyra and Román Piña Chan. The head had collapsed into a ravine under its own weight and was found face down on its left hand side. In 1970 it was transported to the Metropolitan Museum of Art in New York for the museum's centenary exhibition. After its return to Mexico, it was placed in the Museo Nacional de Antropología in Mexico City. It is sculpted with a net-like head covering joined together with sculpted beads. A covering descends from under the headdress to cover the back half of the neck. The headband is divided into four strips and begins above the right ear, extending around the entire head. A short strap descends from either side of the head to the ear. The ear ornaments are complex and are larger at the front of the ear than at the back. The face is that of an ageing male with the forehead creased in a frown, wrinkles under the eyes, sagging cheeks and deep creases on either side of the nose. The face is somewhat asymmetric, possibly due to errors in the execution of the monument. | https://en.wikipedia.org/wiki?curid=35721801 | 164,307 |
1,598,684 | In his fifth book, "Manufacturing Militarism: U.S. Government Propaganda in the War on Terror", (Stanford University Press, 2021, ) also co-authored with Abigail R. Hall, they explain how propaganda operates in democratic politics and why it matters for citizens of democratic countries. They specifically focus on government-produced propaganda targeting the domestic populace within the United States in the post-9/11 period. They show that the U.S. government has purposefully provided partial or misleading information about the actual threats to the security of U.S. persons while contributing to a broader culture of militarism. Towards the end of the book, they offer potential institutional reforms that would limit the extent to which propaganda can distort the ability of the citizenry to form informed opinions. | https://en.wikipedia.org/wiki?curid=13784343 | 1,597,784 |
1,708,401 | The first step towards the electric piano was by Harold Rhodes who developed various prototypes using parts from B-17 aircraft that were being scrapped. He received a medal since the resulting keyboard was used as therapy for people rehabilitating from injuries from WW2. (It is small enough to set on a stand over a patient's bed in a hospital, looking something like a miniature grand piano in shape.) Instructions were made and people built this "pre-piano" which amplifies the signals generated in a pickup from the vibration of stainless steel rods tapered near the steel base they are driven into holes in. Piano type wooden hammers are used to strike them. It was a three octave (E to F for 38 notes) instrument. A tube amplifier drove a speaker pointing out the bottom. | https://en.wikipedia.org/wiki?curid=56945879 | 1,707,443 |
1,156,880 | Unlike many other sensory systems, the human visual system – components from the eye to neural circuits – develops largely after birth, especially in the first few years of life. At birth, visual structures are fully present yet immature in their potentials. From the first moment of life, there are a few innate components of an infant's visual system. Newborns can detect changes in brightness, distinguish between stationary and kinetic objects, as well as follow kinetic objects in their visual fields. However, many of these areas are very poorly developed. With physical improvements such as increased distances between the cornea and retina, increased pupil dimensions, and strengthened cones and rods, an infant's visual ability improves drastically. The neuro- pathway and physical changes that underlie these improvements in vision remains a strong focus in research. Because of an infant's inability to verbally express their visual field, growing research in this field relies heavily on nonverbal cues including an infant's perceived ability to detect patterns and visual changes. The major components of the visual system can be broken up into visual acuity, depth perception, color sensitivity, and light sensitivity. | https://en.wikipedia.org/wiki?curid=5209682 | 1,156,269 |
235,203 | Adult patients with congenital cardiac disease are on the rise at a rate of about 5% per year, outpacing the pediatric population. Right ventricular volume overload form pulmonary insufficiency, right ventricular aneurysm from outflow patch or ventriculotomy, distal pulmonary artery obstruction, ventricular hypertrophy, chamber enlargement, biventricular dysfunction, and aortic root dilation and insufficient are all long-term complications seen in these patients. Arrhythmia, heart failure, and complications from reoperations are the three primary causes of death in individuals with corrected tetralogy of Fallot. QRS duration greater than 180 milliseconds, older age at repair (greater than three years), significant pulmonary valve or tricuspid valve regurgitation, history of syncope, multifocal premature ventricular contractions, and ventricular tachycardia are some of the factors associated with sudden death after 30 years of procedure. Pulmonary insufficiency is the most common reason for reoperation, and pulmonary valve replacement criteria have traditionally been based on the severity of the regurgitant fraction on a magnetic resonance or CT scan. Right and left ventricular end-systolic and end-diastolic volume indices, ejection fractions, and the existence of aneurysm generating obstructive outflow are all parameters seen in this research. Exercise intolerance, heart failure signs and symptoms, syncope, and prolonged ventricular tachycardia are all possible symptoms. A transcatheter pulmonary valve method can also be used to replace a pulmonary valve. | https://en.wikipedia.org/wiki?curid=242284 | 235,084 |
4,002 | "God of War III" was first mentioned by Cory Barlog at a "God of War II" launch event, and it was officially announced at the 2008 Electronic Entertainment Expo (E3). After serving as game director during the first eight months of development, Barlog left Santa Monica for other opportunities and Stig Asmussen took on the role, having previously been the lead environment artist and art director on "God of War" and "God of War II", respectively. Asmussen said that one of the greatest challenges in developing "God of War III" for the PlayStation 3 was the "complexity of everything"; individual tasks, such as designing Helios' decapitation, could take a year because the "level of detail [that was] expected [was] so high and intricate, it [crossed] multiple departments." He said that the PlayStation 3's hardware capabilities allowed more flexibility in character creation and interaction with the environment.<ref name="IGN12/8/09"></ref><ref name="GamePro11/4/09"></ref> The engine for "God of War III" was ported from the first two installments to the PlayStation 3. As the game was being developed, the code department swapped out PlayStation 2 components with PlayStation 3 components. They replaced the renderer, the particle system, and the collision system. Although they were re-using the engine from "God of War II", the core engine for "God of War III" was brand new. Between E3 2009 and the time the game shipped, morphological anti-aliasing (MLAA) was added, which graphics engineer Ben Diamand said "improved edges dramatically and saved substantial amounts of frame-rate." Diamand also said that "depth-of-field, motion blur, crepuscular 'God' rays and refraction were either added or improved in quality and speed" during that same time period.<ref name="Euro5/4/13"></ref> | https://en.wikipedia.org/wiki?curid=16282491 | 4,002 |
55,733 | Like the naval (1B) version, Centurion uses Ku-band radar and FLIR to detect and track incoming projectiles, and is also capable of engaging surface targets, with the system able to reach a minus-25-degree elevation. The Centurion is reportedly capable of defending a area. One major difference between the land- and sea-based variants is the choice of ammunition. Whereas naval Phalanx systems fire tungsten armor-piercing rounds, the C-RAM uses the 20–mm HEIT-SD (High-Explosive Incendiary Tracer, Self-Destruct) ammunition, originally developed for the M163 Vulcan Air Defense System. These rounds explode on impact with the target, or on tracer burnout, thereby greatly reducing the risk of collateral damage from rounds that fail to hit their target. | https://en.wikipedia.org/wiki?curid=89872 | 55,710 |
827,698 | The field of statistical mechanics (beginning with the work of Ludwig Boltzmann in developing the Boltzmann equation) relieved many physicists of this concern. From this discipline, we now know that macroscopic properties may all be determined from properties on a microscopic scale where entropy is more "real" than temperature itself ("see Thermodynamic temperature"). Microscopic kinetic fluctuations among particles cause entropic loss, and this energy is unavailable for work because these fluctuations occur randomly in all directions. The anthropocentric act is taken, in the eyes of some physicists and engineers today, when someone draws a hypothetical boundary, in fact, he says: "This is my system. What occurs beyond it is surroundings." In this context, exergy is sometimes described as an anthropocentric property, both by those who use it and those who don't. Entropy is viewed as a more fundamental property of matter. | https://en.wikipedia.org/wiki?curid=1075005 | 827,254 |
645,645 | Reflecting the varied electrification schemes on the Northeast Corridor the locomotives could operate at three different voltages: 11 kV 25 Hz AC, 12.5 kV 60 Hz AC and 25 kV 60 Hz. A pair of Faiveley DS-11 two-stage pantographs, one at each end of the locomotive, collected power from the overhead catenary wire. Thyristor converters stepped down the high-voltage AC to provide DC power at a much lower voltage to four traction motors, one per axle. As built the AEM-7 was rated at , with a starting tractive effort of and a continuous tractive effort of . Its maximum speed was . A separate static converter supplied 500 kW 480 V head-end power (HEP) for passenger comfort. This was sufficient to supply heating, lighting, and other electrical needs in 8-10 Amfleet cars. | https://en.wikipedia.org/wiki?curid=390246 | 645,305 |
719,346 | The tendency is to relate equivalence partitioning to so called black box testing which is strictly checking a software component at its interface, without consideration of internal structures of the software. But having a closer look at the subject there are cases where it applies to grey box testing as well. Imagine an interface to a component which has a valid range between 1 and 12 like the example above. However internally the function may have a differentiation of values between 1 and 6 and the values between 7 and 12. Depending upon the input value the software internally will run through different paths to perform slightly different actions. Regarding the input and output interfaces to the component this difference will not be noticed, however in your grey-box testing you would like to make sure that both paths are examined. To achieve this it is necessary to introduce additional equivalence partitions which would not be needed for black-box testing. For this example this would be: | https://en.wikipedia.org/wiki?curid=1709984 | 718,966 |
566,676 | The state retained the monopoly of issuing coinage, and had the power to intervene in other important sectors of the economy. It exercised formal control over interest rates, and set the parameters for the activity of the guilds and corporations in Constantinople, in which the state has a special interest (e.g. the sale of silk) or whose members exercised a profession that was of importance for trade. The emperor and his officials intervened at times of crisis to ensure the provisioning of the capital and to keep down the price of cereals. For this reason, the empire strictly controlled both the internal circulation of commodities, and the international trade (certainly in intent; to a considerable degree also in practice). Additionally, the state often collected part of the surplus in the form of tax, and put it back into circulation, through redistribution in the form of salaries to state officials of the army, or in the form of investment in public works, buildings, or works of art. | https://en.wikipedia.org/wiki?curid=11418423 | 566,386 |
629,348 | In 1964, Ingo Rechenberg and Hans-Paul Schwefel introduce the paradigm of evolution strategies in Germany. Since traditional gradient descent techniques produce results that may get stuck in local minima, Rechenberg and Schwefel proposed that random mutations (applied to all parameters of some solution vector) may be used to escape these minima. Child solutions were generated from parent solutions, and the more successful of the two was kept for future generations. This technique was first used by the two to successfully solve optimization problems in fluid dynamics. Initially, this optimization technique was performed without computers, instead relying on dice to determine random mutations. By 1965, the calculations were performed wholly by machine. | https://en.wikipedia.org/wiki?curid=268020 | 629,010 |
818,965 | One of the first true tests of this new technology was in the aftermath of the Saint Valentine's Day Massacre in 1929. During the Prohibition Era, competing gang members were fighting over bootlegging operations within the city of Chicago. Members of the Chicago Outfit and the Egan's Rats led by Al Capone attempted to remove all competition from Chicago by eliminating the North Side Gang leader Bugs Moran. The massacre missed Moran, who was not present, but killed seven members of the North Side Gang. The murderers attempted to cover up their crime by posing as police officers, even dressing in police uniforms. Witnesses saw two "officers" leaving the scene, which implicated the Chicago police department as the perpetrators of the massacre. High levels of police corruption during that time period made it seem likely that the police department committed the killings. The investigation stalled until December 1929 when Fred Burke, a member of the Egan's Rats, shot and killed a police officer in St. Joseph, Michigan. Officers searching for Burke were led to a home in nearby Stevensville. While Burke was not there, inside officers found an arsenal of weapons including two Thompson submachine guns. The Chicago police department was contacted and the weapons were brought back to Chicago for testing. Goddard was asked to compare the weapons to collected evidence found at the massacre using his new "ballistic-forensics" technique. After test firing the guns, Goddard proved that the weapons were those used to kill the members of the North Side Gang, absolving the Chicago police department of all involvement. The successful use of Goddard's technique resulted in the solidification of his place as the father of forensic firearm examination. | https://en.wikipedia.org/wiki?curid=50103453 | 818,525 |
1,926,255 | The polymerase chain reaction is the most widely used method for "in vitro" DNA amplification for purposes of molecular biology and biomedical research. This process involves the separation of the double-stranded DNA in high heat into single strands (the denaturation step, typically achieved at 95–97 °C), annealing of the primers to the single stranded DNA (the annealing step) and copying the single strands to create new double-stranded DNA (the extension step that requires the DNA polymerase) requires the reaction to be done in a thermal cycler. These bench-top machines are large, expensive and costly to run and maintain, limiting the potential applications of DNA amplification in situations outside the laboratory (e.g., in the identification of potentially hazardous micro-organisms at the scene of investigation, or at the point of care of a patient). Although PCR is usually associated with thermal cycling, the original patent by Mullis et al. disclosed the use of a helicase as a means for denaturation of double stranded DNA thereby including isothermal nucleic acid amplification. | https://en.wikipedia.org/wiki?curid=803558 | 1,925,151 |
166,060 | Presently, treatments make it possible for quicker recovery. If the tear is not serious, physical therapy, compression, elevation and icing the knee can heal the meniscus. Meniscus tears are more likely to heal on their own if they are in what physicians call the "red zone," or the outer edge of the meniscus where blood supply is present. More serious tears may require surgical procedures. Surgery, however, does not appear to be better than non-surgical care. In the long term, degenerative meniscal tears are often associated with osteoarthritis. This leads to poor outcomes regardless of treatment type. In the short term, studies have shown arthroscopic partial meniscectomy (APM) is a more effective treatment with regards to function and pain management. | https://en.wikipedia.org/wiki?curid=15435205 | 165,975 |
341,035 | Stock: H-S Precision PST-024, the model with the fixed cheek piece, adjustable LOP and hinged floorplate. The stock secures the action via an aluminum bedding block to keep it rigid. The barrel is free floating. A twin-strut extension that pulls out of the butt allows a 2-inch [50.8mm] adjustment to length-of-pull, as well as allowing for the weapon to fit inside the M-1950 Weapon Container for Airborne Operations. This is effected by a thick wheel on a central grooved pillar for adjusting the length and a thin locking ring behind it locks the thick wheel in place. The stock is primarily made from a polymer foam reinforced with fiberglass, carbon fiber, and Kevlar to reduce weight and then painted with a heavy duty polane paint. They were rigorously tested before being approved by Remington and the military. | https://en.wikipedia.org/wiki?curid=504626 | 340,854 |
1,185,325 | One answer to this problem was advanced by the followers of Pythagoras (c. 582–507 BC), who saw number as the fundamental unchanging entity underlying all the structure of the universe. Although it is difficult to separate fact from legend, it appears that some Pythagoreans believed matter to be made up of ordered arrangements of points according to geometrical principles: triangles, squares, rectangles, or other figures. Other Pythagoreans saw the universe arranged on the basis of numbers, ratios, and proportions, much like musical scales. Philolaus, for instance, held that there were ten heavenly bodies because the sum of 1 + 2 + 3 + 4 gives the perfect number 10. Thus, the Pythagoreans were some of the first to apply mathematical principles to explain the rational basis of an orderly universe—an idea that was to have immense consequences in the development of scientific thought. | https://en.wikipedia.org/wiki?curid=1694427 | 1,184,696 |
1,184,450 | Measurement of the system's state at this point would reveal an up spin at position 1 or a down spin at position −1, both with probability 1/2. Repeating the procedure would correspond to a classical simple random walk on formula_25. In order to observe non-classical motion, no measurement is performed on the state at this point (and therefore do not force a collapse of the wave function). Instead, repeat the procedure of rotating the spin with the coin flip operator and conditionally jumping with formula_37. This way, quantum correlations are preserved and different position states can interfere with one another. This gives a drastically different probability distribution than the classical random walk (Gaussian distribution) as seen in the figure to the right. Spatially one sees that the distribution is not symmetric: even though the Hadamard coin gives both up and down spin with equal probability, the distribution tends to drift to the right when the initial spin is formula_45. This asymmetry is entirely due to the fact that the Hadamard coin treats the formula_45 and formula_47 state asymmetrically. A symmetric probability distribution arises if the initial state is chosen to be | https://en.wikipedia.org/wiki?curid=12485744 | 1,183,823 |
446,192 | Metaigneous and metavolcanic rocks form the largest component of cratons and are high in silica. Igneous and volcanic rocks are also high in silica but with non-metamorphosed rock, weathering becomes faster and the mobilization of ions is more widespread. Rocks high in silica produce silicic acid as a weathering product. There are few rock types that lead to localized enrichment of some of the biologically limiting elements like phosphorus (P) and nitrogen (N). Phosphatic shale (< 15% PO) and phosphorite (> 15% PO) form in anoxic deep water basins that preserve organic material. Greenstone (metabasalt), phyllite and schist release up to 30–50% of the nitrogen pool. Thick successions of carbonate rocks are often deposited on craton margins during sea level rise. The widespread dissolution of carbonate and evaporate minerals leads to elevated levels of Mg, , Sr, Na, Cl and ions in aqueous solution. | https://en.wikipedia.org/wiki?curid=1203155 | 445,976 |
36,499 | In November 1960, John F. Kennedy was elected president after a campaign that promised American superiority over the Soviet Union in the fields of space exploration and missile defense. Up to the election of 1960, Kennedy had been speaking out against the "missile gap" that he and many other senators felt had developed between the Soviet Union and the United States due to the inaction of President Eisenhower. Beyond military power, Kennedy used aerospace technology as a symbol of national prestige, pledging to make the US not "first but, first and, first if, but first period". Despite Kennedy's rhetoric, he did not immediately come to a decision on the status of the Apollo program once he became president. He knew little about the technical details of the space program, and was put off by the massive financial commitment required by a crewed Moon landing. When Kennedy's newly appointed NASA Administrator James E. Webb requested a 30 percent budget increase for his agency, Kennedy supported an acceleration of NASA's large booster program but deferred a decision on the broader issue. | https://en.wikipedia.org/wiki?curid=1461 | 36,487 |
1,211,758 | Expedition 2 March 8 to August 22, 2001, was a mission to the International Space Station and Helms was a member of the second crew to inhabit the International Space Station Alpha. The "Expedition 2" crew (two American astronauts and one Russian cosmonaut) launched on March 8, 2001, on board STS-102 "Discovery" and successfully docked with the station on March 9, 2001. The "Expedition 2" crew installed and conducted tests on the Canadian-made Space Station Robotic arm (SSRMS), conducted internal and external maintenance tasks (Russian and American), in addition to medical and science experiments. During her stay on board, Helms installed the airlock (brought up on the STS-104 mission) using the SSRM. She and her crewmates also performed a 'fly around' of the Russian "Soyuz" spacecraft and welcomed the visiting Soyuz crew that included the first space tourist, Dennis Tito. On March 11 she performed a world-record 8 hour and 56 minute spacewalk to install hardware to the external body of the laboratory module. Helms spent a total of 163 days aboard the space station. She returned to Earth with the STS-105 crew aboard "Discovery" on August 22, 2001. | https://en.wikipedia.org/wiki?curid=604816 | 1,211,106 |
1,867,839 | Aichi Prefecture is undertaking to nurture and promote the aerospace industry in response to the designation of "Asia No. 1 Aerospace Industry Cluster Formation Special Zone" in the International Special Strategy Comprehensive Special Zone, and around the Nagoya Aerodrome have long since been Mitsubishi Heavy Industries Nagoya Aerospace Systems In addition to the location of the manufacturing factory (Nagoya), Mitsubishi Aircraft is constructing a new MRJ final assembly plant, which is the aircraft development and production base. From being expected as a place for human resource development and industrial tourism in the future, the prefecture will hold "Air Museum Field" as a "prefectural Nagoya Airport visitor base visiting facility maintenance project" at a press conference on May 15, 2015 we announced to construct. | https://en.wikipedia.org/wiki?curid=55658672 | 1,866,763 |
1,381,469 | Mathematical Reviews was founded by Otto E. Neugebauer in 1940 as an alternative to the German journal "Zentralblatt für Mathematik", which Neugebauer had also founded a decade earlier, but which under the Nazis had begun censoring reviews by and of Jewish mathematicians. The goal of the new journal was to give reviews of every mathematical research publication. As of November 2007, the "Mathematical Reviews" database contained information on over 2.2 million articles. The authors of reviews are volunteers, usually chosen by the editors because of some expertise in the area of the article. It and "Zentralblatt für Mathematik" are the only comprehensive resources of this type. (The Mathematics section of "Referativny Zhurnal" is available only in Russian and is smaller in scale and difficult to access.) Often reviews give detailed summaries of the contents of the paper, sometimes with critical comments by the reviewer and references to related work. However, reviewers are not encouraged to criticize the paper, because the author does not have an opportunity to respond. The author's summary may be quoted when it is not possible to give an independent review, or when the summary is deemed adequate by the reviewer or the editors. Only bibliographic information may be given when a work is in an unusual language, when it is a brief paper in a conference volume, or when it is outside the primary scope of the Reviews. Originally the reviews were written in several languages, but later an "English only" policy was introduced. Selected reviews (called "featured reviews") were also published as a book by the AMS, but this program has been discontinued. | https://en.wikipedia.org/wiki?curid=1485646 | 1,380,706 |
911,639 | AMQP 1.0 was released by the AMQP working group on 30 October 2011, at a conference in New York. At the event Microsoft, Red Hat, VMware, Apache, INETCO and IIT Software demonstrated software running the protocol in an interoperability demonstration. The next day, on 1 November 2011, the formation of an OASIS Technical Committee was announced to advance this contributed AMQP version 1.0 through the international open standards process. The first draft from OASIS was released in February 2012, the changes as compared to that published by the Working Group being restricted to edits for improved clarity (no functional changes). The second draft was released for public review on 20 June (again with no functional changes), and AMQP was approved as an OASIS standard on 31 October 2012. | https://en.wikipedia.org/wiki?curid=5657545 | 911,160 |
1,359,295 | The Tendaguru Beds as a fossil deposit were first discovered in 1906, when German pharmacist, chemical analyst and mining engineer Bernhard Wilhelm Sattler, on his way to a mine south of the Mbemkure River in German East Africa (today Tanzania), was shown by his local staff enormous bones weathering out of the path near the base of Tendaguru Hill, south of Mtapaia (close to Nambiranji village, Mipingo ward, northwest of Lindi town). Because of its morphology, the hill was locally known as "steep hill": "tendaguru" in the language of the local Wamwera people. Sattler sent a report of the discoveries that found its way to German palaeontologist Eberhard Fraas, then on a round trip through Africa, who visited the site in 1907 and with the aid of Sattler recovered two partial skeletons of enormous size. | https://en.wikipedia.org/wiki?curid=9955111 | 1,358,544 |
2,172,883 | The initiative began in 2001, funded from the state's settlement with the tobacco industry. Other life sciences greenhouses in Philadelphia and Pittsburgh also received seed money from the settlement. LSGPA partners with a range of institutions, including local research universities, colleges, medical centers, economic development agencies and companies of various sizes to identify needs and opportunities. It then works to help transfer technologies, develop new companies, provide support for existing companies (particularly those seeking to expand or relocate), and ensure that the infrastructure to support a thriving life sciences industry keeps pace with development. | https://en.wikipedia.org/wiki?curid=8731629 | 2,171,641 |
308,653 | The "rough form" of LPS has a lower molecular weight due to the absence of the O polysaccharide. In its place is a short oligosaccharide: this form is known as Lipooligosaccharide (LOS), and is a glycolipid found in the outer membrane of some types of Gram-negative bacteria, such as "Neisseria" spp. and "Haemophilus" spp. LOS plays a central role in maintaining the integrity and functionality of the outer membrane of the Gram negative cell envelope. LOS play an important role in the pathogenesis of certain bacterial infections because they are capable of acting as immunostimulators and immunomodulators. Furthermore, LOS molecules are responsible for the ability of some bacterial strains to display molecular mimicry and antigenic diversity, aiding in the evasion of host immune defenses and thus contributing to the virulence of these bacterial strains. In the case of "Neisseria meningitidis", the lipid A portion of the molecule has a symmetrical structure and the inner core is composed of 3-deoxy-D-manno-2-octulosonic acid (KDO) and heptose (Hep) moieties. The outer core oligosaccharide chain varies depending on the bacterial strain. | https://en.wikipedia.org/wiki?curid=412942 | 308,488 |
1,527,602 | Richard Fikentscher got Semm interested in the treatment of infertility. In 1957, Fikentscher, Semm and three other physicians founded of the Deutsche Gesellschaft zum Studium der Fertilität und Sterilität, renamed Deutsche Gesellschaft für Reproduktionsmedizin in 1998. In the 1960s Semm started to use laparoscopy – he named it ‘’pelviscopy’’ - for gynecologic indications, initially as a diagnostic tool, but soon realizing that the laparoscopic approach had potential for interventive surgery. His experience as toolmaker let him to found the WISAP medical instrument company in 1959 allowing him to developed numerous instruments among them an automated electronic insufflator, uterine manipulators, thermocoagulators to stop bleeding, and extra- and intracorporeal endoscopic knotting devices to tie off vessels or remove organs. | https://en.wikipedia.org/wiki?curid=47818248 | 1,526,738 |
628,146 | Also in 1976 Videcom international with British Airways, British Caledonian and CCL launched Travicom, the world's first multi-access reservations system (wholly based on Videcom technology), forming a network providing distribution for initially two and subsequently 49 subscribing international airlines (including British Airways, British Caledonian, Trans World Airlines, Pan Am, Qantas, Singapore Airlines, Air France, Lufthansa, SAS, Air Canada, KLM, Alitalia, Cathay Pacific and Japan Airlines) to thousands of travel agents in the UK. It allowed agents and airlines to communicate via a common distribution language and network, handling 97% of UK airline business trade bookings by 1987. The system went on to be replicated by Videcom in other areas of the world including the Middle East (DMARS), New Zealand, Kuwait (KMARS), Ireland, Caribbean, United States and Hong Kong. Travicom was a trading name for Travel Automation Services Ltd. When British Airways (who by then owned 100% of Travel Automation Services Ltd) chose to participate in the development of the Galileo system Travicom changed its trading name to Galileo UK and a migration process was put in place to move agencies from Travicom to Galileo. | https://en.wikipedia.org/wiki?curid=1155952 | 627,811 |
1,179,805 | Flanagan's work was carried out as part of the Aviation Psychology Program of the United States Army Air Forces during World War II, where Flanagan conducted a series of studies focused on differentiating effective and ineffective work behaviors. Flanagan went on to found American Institutes for Research continuing to use the critical incident technique in a variety of research. Since then CIT has spread as a method to identify job requirements, develop recommendations for effective practices, and determine competencies for a vast number of professionals in various disciplines. In particular, it has been used in service research. | https://en.wikipedia.org/wiki?curid=2943250 | 1,179,181 |
1,226,931 | For simplicity's sake, these random percentages have been assigned to the six cost drivers of transportation this example entails. After this step, the cost drivers are being analyzed while the analyzing party (be it the business itself or an external agency) tries to examine possibilities to cut current expenses. The business might find 42% of total costs to be too much for motor fuel and might either want to look for an alternative supplier or change to more fuel efficient trucks. The cost breakdown analysis is even more effective when repeated constantly, so that changes in the respective shares in total costs of the various cost drivers can be tracked down. Over a five-year period, the share of expenses for tires might have risen from 5% to 8%, accompanied by a decrease of expenses for personnel from 35% to 32%, which featured the dismissal of workforce. The business might want to consider contracting a cheaper supplier of tires and reemploy its former employees. | https://en.wikipedia.org/wiki?curid=48763967 | 1,226,270 |
1,677,365 | The Etruscans, like the contemporary cultures of Ancient Greece and Ancient Rome had a persistent military tradition. In addition to marking the rank and power of certain individuals in Etruscan culture, warfare was a considerable economic boon to Etruscan civilization. Like many ancient societies, the Etruscans conducted campaigns during summer months; raiding neighboring areas, attempting to gain territory and combating piracy as a means of acquiring valuable resources such as land, prestige goods and slaves. It is also likely individuals taken in battle would be ransomed back to their families and clans at high cost. Prisoners could also potentially be sacrificed on tombs to honor fallen leaders of Etruscan society, not unlike the sacrifices made by Achilles for Patroclus. | https://en.wikipedia.org/wiki?curid=21563120 | 1,676,423 |
1,342,853 | In January 2004 SEAS was evaluated by the Joint Innovation and Experimentation Directorate (J9) of the US Joint Forces Command (JFCOM) for its ability to help simulate "the non-kinetic aspects of combat, things like the diplomatic, economic, political, infrastructure and social issues" at the Purdue Technology Park during Breaking Point 2004, an environment-shaping war game resulting in the conclusion that it "moves us from the current situation where everyone comes together and sits around a table discussing what they would do, to a situation where they actually play in the simulation and their actions have consequences." | https://en.wikipedia.org/wiki?curid=12018606 | 1,342,117 |
1,712,283 | The goal of the plasma generators is to convert the electric energy into the energy of charged and neutral particles – electrons, ions, atoms and molecules – which then would produce large quantities of chemical compounds of hydrogen, nitrogen and oxygen, in particular short-lived highly reactive species. Bombardment of the substrate with all constituent plasma species cleans and chemically activates the surface. In addition, at the contact points of discharge filaments the surface can locally reach high temperatures. This modifies the topography of the surface improving mechanical binding of the adhesive. | https://en.wikipedia.org/wiki?curid=8198899 | 1,711,318 |
1,448,472 | Other proof-of-concept applications under review involve high sensitivity biological and chemical sensing. They may enable the development of optical sensors that exploit the confinement of surface plasmons within a certain type of Fabry-Perot nano-resonator. This tailored confinement allows efficient detection of specific bindings of target chemical or biological analytes using the spatial overlap between the optical resonator mode and the analyte ligands bound to the resonator cavity sidewalls. Structures are optimized using finite difference time domain electromagnetic simulations, fabricated using a combination of electron beam lithography and electroplating, and tested using both near-field and far-field optical microscopy and spectroscopy. | https://en.wikipedia.org/wiki?curid=30869356 | 1,447,656 |
639,347 | A diver at the end of a long or deep dive may need to do decompression stops to avoid decompression sickness, also known as "the bends". Metabolically inert gases in the diver's breathing gas, such as nitrogen and helium, are absorbed into body tissues when breathed under high pressure, mainly during the deep phase of the dive. These dissolved gases must be released slowly from the body tissues by controlling the ascent rate to restrict the formation and growth of bubbles. This is usually done by pausing or "doing stops" at various depths during the ascent to the surface. Most technical divers breathe oxygen enriched breathing gas mixtures such as nitrox and pure oxygen during long-duration decompression, as this increases the rate of inert gas elimination. Elimination of inert gases continues during the surface intervals (time spent on the surface between dives), which must be considered when planning subsequent dives. A decompression obligation is also referred to as a "soft", or "physiological" ceiling. | https://en.wikipedia.org/wiki?curid=291242 | 639,008 |
1,064,565 | Cylinder deactivation is achieved by keeping the intake and exhaust valves closed for a particular cylinder. By keeping the intake and exhaust valves closed, it creates an "air spring" in the combustion chamber – the trapped exhaust gases (kept from the previous charge burn) are compressed during the piston’s upstroke and push down on the piston during its downstroke. The compression and decompression of the trapped exhaust gases have an equalising effect – overall, there is virtually no extra load on the engine. In the latest breed of cylinder deactivation systems, the engine management system is also used to cut fuel delivery to the disabled cylinders. The transition between normal engine operation and cylinder deactivation is also smoothed, using changes in ignition timing, cam timing and throttle position (thanks to electronic throttle control). In most instances, cylinder deactivation is applied to relatively large displacement engines that are particularly inefficient at light load. In the case of a V12, up to 6 cylinders can be disabled. | https://en.wikipedia.org/wiki?curid=1390282 | 1,064,011 |
1,216,458 | He became a prominent figure of nineteenth-century Australian science and became involved in significant issues of Australian and New Guinea history. Writing letters to Australian papers, Miklouho-Maclay expressed his opposition to the labour and slave trade ("blackbirding") in Australia, New Caledonia and the Pacific, as well as his opposition to the British and German colonial expansion in New Guinea. While in Australia, he built the first biological research station in the Southern Hemisphere, was elected to the Linnean Society of New South Wales, was instrumental in establishing the Australasian Biological Association, stayed at the elite Australian Club, became the intimate of the leading amateur scientist and political figure Sir William Macleay, and married Margaret-Emma Robertson, the daughter of the Premier of New South Wales. His three grandsons have all contributed to the public life of Australia. | https://en.wikipedia.org/wiki?curid=1550260 | 1,215,806 |
156,516 | The star hosts four other planets discovered so far, although Kepler-186 b, c, d, and e (in order of increasing orbital radius), being too close to their star, are considered too hot to have liquid water. The four innermost planets are probably tidally locked, but Kepler-186f is in a higher orbit, where the star's tidal effects are much weaker, so the time could have been insufficient for its spin to slow down significantly. Because of the very slow evolution of red dwarfs, the age of the Kepler-186 system was poorly constrained, although it is likely to be greater than a few billion years. Recent results have placed the age at around 4 billion years. The chance that it is tidally locked is approximately 50%. Since it is closer to its star than Earth is to the Sun, it will probably rotate much more slowly than Earth; its day could be weeks or months long (see Tidal effects on rotation rate, axial tilt and orbit). | https://en.wikipedia.org/wiki?curid=42518279 | 156,444 |
177,507 | "Total Quality Management (TQM) in the Department of Defense is a strategy for continuously improving performance at every level, and in all areas of responsibility. It combines fundamental management techniques, existing improvement efforts, and specialized technical tools under a disciplined structure focused on continuously improving all processes. Improved performance is directed at satisfying such broad goals as cost, quality, schedule, and mission need and suitability. Increasing user satisfaction is the overriding objective. The TQM effort builds on the pioneering work of Dr. W. E. Deming, Dr. J. M. Juran, and others, and benefits from both private and public sector experience with continuous process improvement." | https://en.wikipedia.org/wiki?curid=143996 | 177,415 |
1,894,502 | The Tigers worked their way back into post-season contention, though, with a three-game winning streak. First, Missouri edged Baylor by seven points on Valentine's Day. Three days later, Anderson won his first game against a ranked opponent by beating 18th-ranked Oklahoma State 75-64 at Gallagher-Iba Arena, a traditionally difficult Big 12 venue. Freshman guard Keon Lawrence led the team with 18 points, and even little-used reserve Glen Dandridge made a three-pointer and scored five points in four minutes of action. The next week, Lawrence—no relation to Matt Lawrence—continued his strong play and came up with one of the season's most exciting plays in a win over the Oklahoma Sooners. Lawrence made the game-winning basket with a turnaround jumper with less than a minute to play, despite not making a field goal in the first half. | https://en.wikipedia.org/wiki?curid=21438663 | 1,893,418 |
1,671,931 | As a result of globalization, supply chains are becoming increasingly more complex. Outsourcing and rising end user quality expectations have resulted in a higher demand for independent TIC services. Businesses are aiming to ensure that products, infrastructures and processes meet the required standards and regulations in terms of quality, health and safety, environmental protection and social responsibility reducing the risk of failure, accidents and disruption. This includes such services as the testing and inspection of bulk carriers and their cargos possibly carrying commodities such as petroleum, grains or livestock. | https://en.wikipedia.org/wiki?curid=56319253 | 1,670,990 |
443,821 | Early commercial digital synthesizers used simple hard-wired digital circuitry to implement techniques such as additive synthesis and FM synthesis. Other techniques, such as wavetable synthesis and physical modeling, only became possible with the advent of high-speed microprocessor and digital signal processing technology. Two other early commercial digital synthesizers were the Fairlight CMI, introduced in 1979, and the New England Digital Synclavier II, introduced in 1979 as an upgrade to the original Synclavier. The Fairlight CMI was the world's first sampling synthesizer, while the Synclavier originally used FM synthesis technology licensed from Yamaha, before adding the world's first 16-bit, real-time hard drive streaming sampler later in 1982. The Fairlight CMI and the Synclavier were both expensive systems, retailing for more than $20,000 in the early 1980s. The cost of digital synthesizers began falling rapidly in the early 1980s. E-mu Systems introduced the Emulator sampling synthesizer in 1982 at a retail price of $7,900. Although not as flexible or powerful as either the Fairlight CMI or the Synclavier, its lower cost and portability made it popular. | https://en.wikipedia.org/wiki?curid=8247 | 443,606 |
1,613,173 | In August 2012, China's National Energy Administration formed a consortium of companies and research institutes, led by the Hydropower and Water Resources Planning and Design General Institute (also known as China Renewable Energy Engineering Institute), to investigate DTP. A bilateral agreement on DTP cooperation was signed between China and the Netherlands on September 27, 2012. Following technical exchange to verify the principles, a modelling study was conducted to select sites. In October 2013, a more in-depth economic analysis study was started to better understand the economic costs and benefits of DTP. | https://en.wikipedia.org/wiki?curid=28748337 | 1,612,268 |
370,488 | To support the Mars-2020 mission, USGS used photos by the High-Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter (MRO) to produce Context Camera (CTX) and Digital Terrain Models (DTM) and orthoimage mosaics. Those images were used by the Terrain Relative Navigation (TRN) feature on the "Perseverance" descent vehicle and helped determine the safest landing location. Using maps created from photos and radar elevation data previously acquired by the MRO and other NASA missions, planetary cartographers manually correlate them with terrain features seen by "Ingenuity's" small and lens-distorted NAV images. After each NAV frame is assigned a georeference, the resulting flight maps are shown at NASA's Mars-2020 tracking service. NAV frames from "Ingenuity" are also used to produce moving images that show the Martian terrain passing under "Ingenuity" during its flights. | https://en.wikipedia.org/wiki?curid=56300556 | 370,294 |
1,308,674 | In November and December 1941, the United States National Defense Research Committee conducted extensive tests between the American Bausch and Lomb M1 stereoscopic rangefinder and the British Barr and Stroud FQ 25 and UB 7 coincidence rangefinders, and concluded "that the tests indicate no important difference in the precision obtainable from the two types of instrument — coincidence and stereoscopic. They do indicate, however, that the difference in performance between large and small instruments is by no means as great as would be anticipated from simple geometrical optics. The report concludes with the belief that stereoscopic and coincidence acuities are about equal. Under favourable conditions existing instruments of the two types perform about equally well, and the choice between them for any given purpose must be based on matters of convenience related to the particular conditions under which they are to be used." | https://en.wikipedia.org/wiki?curid=13817915 | 1,307,958 |
746,855 | Although cicada killers are large, female cicada-killer wasps are not aggressive and rarely sting unless they are grasped roughly, stepped upon with bare feet, or caught in clothing. One author who has been stung indicates that for him, the stings are not much more than a "pinprick". Males aggressively defend their perching areas on nesting sites against rival males, but they have no stinger. Although they appear to attack anything that moves near their territories, male cicada killers are actually investigating anything that might be a female cicada killer ready to mate. Such close inspection appears to many people to be an attack, but male and female cicada killers do not land on people with the intent to sting. If handled roughly, females will sting, and males will jab with a sharp spine on the tip of their abdomen. Both sexes are well equipped to bite, as they have large jaws, but they do not appear to grasp human skin and bite. They are generally not aggressive towards humans and usually fly away when swatted at, rather than attacking. | https://en.wikipedia.org/wiki?curid=648060 | 746,460 |
2,097,501 | The XBI technique has been shown to be a sensitive method for spatially resolved mapping of the local orientational properties of anisotropic materials. In the case of organic materials, the technique may be applied to study the orientational properties of individual molecules and/or bonds (most applications of the technique so far have focused on studies of orientational ordering of C–Br bonds, from XBI measurements carried out using incident linearly polarized X-rays tuned to the bromine K-edge). Applications of the technique have included the study of changes in molecular orientations associated with order-disorder phase transitions in solids and characterization of phase transitions in liquid crystalline materials. XBI can also be exploited for spatially resolved analysis of orientationally distinct domains in materials, giving information the sizes of domains, the orientational relationships between domains, and the nature of domain boundaries. | https://en.wikipedia.org/wiki?curid=65426864 | 2,096,293 |
939,666 | Other cross-market LCOE estimates are criticized for basing their calculation on undisclosed portfolio of cherry-picked projects that were significantly delayed due to various reasons, but not include projects that were built in time and within the budget. For example, Bloomberg New Energy Finance (BNEF), based on undisclosed portfolio of projects, estimated nuclear power LCOE at €190-375/MWh which is up to 900% higher than the published LCOE of €30/MWh for an actual existing Olkiluoto nuclear power plant, even after accounting for construction delays in OL3 block (although, this number is based on an average LCOE with new and old reactors). Based on the published methodology details, it has been pointed out that BNEF assumed cost of capital 230% higher than the actual one (1.56%), fixed operating costs at 300% higher than actual and nameplate power lower (1400 MW) than actual 1600 MW, all of which contributed to significant overestimate in price. | https://en.wikipedia.org/wiki?curid=10838742 | 939,165 |
1,308,721 | The primary method of evaluation is a comparison of the predicted model α-carbon positions with those in the target structure. The comparison is shown visually by cumulative plots of distances between pairs of equivalents α-carbon in the alignment of the model and the structure, such as shown in the figure (a perfect model would stay at zero all the way across), and is assigned a numerical score GDT-TS (Global Distance Test—Total Score) describing percentage of well-modeled residues in the model with respect to the target. Free modeling (template-free, or "de novo") is also evaluated visually by the assessors, since the numerical scores do not work as well for finding loose resemblances in the most difficult cases. High-accuracy template-based predictions were evaluated in CASP7 by whether they worked for molecular-replacement phasing of the target crystal structure with successes followed up later, and by full-model (not just α-carbon) model quality and full-model match to the target in CASP8. | https://en.wikipedia.org/wiki?curid=461517 | 1,308,005 |
1,483,805 | Isotopic reference materials exist for non-traditional isotope systems (elements other than hydrogen, carbon, oxygen, nitrogen, and sulfur), including lithium, boron, magnesium, calcium, iron, and many others. Because the non-traditional systems were developed relatively recently, the reference materials for these systems are more straightforward and less numerous than for the traditional isotopic systems. The following table contains the material defining the δ=0 for each isotopic scale, the 'best' measurement of the absolute isotopic fractions of an indicated material (which is often the same as the material defining the scale, but not always), the calculated absolute isotopic ratio, and links to lists of isotopic reference materials prepared by the Commission on Isotopic Abundances and Atomic Weight (part of the International Union of Pure and Applied Chemistry (IUPAC)). A summary list of non-traditional stable isotope systems is available here, and much of this information is derived from Brand "et al." (2014). In addition to the isotope systems listed in Table 8, ongoing research is focused on measuring the isotopic composition of barium (Allmen "et al.," 2010; Miyazaki "et al.," 2014; Nan "et al"., 2015) and vanadium (Nielson "et al.", 2011). Specpure Alfa Aesar is an isotopically well-characterized vanadium solution (Nielson "et al.", 2011). Furthermore, fractionation during chemical processing can be problematic for certain isotopic analyses, such as measuring heavy isotope ratios following column chromatography. In these cases reference materials can be calibrated for particular chemical procedures. | https://en.wikipedia.org/wiki?curid=52796143 | 1,482,969 |
347,565 | Oconee Forest Park, Lake Herrick, and the Herrick Creek Loop are facilities for use and enjoyment of UGA students and staff. Named for Allyn M. Herrick, former Dean of the School of Forest Resources, Lake Herrick was commissioned by the School in 1982 as a recreational resource for UGA. Lake Herrick is a prominent feature within Oconee Forest Park that is a 60-acre natural area nestled behind the Intramural Fields. The area provides recreational opportunities. An accessible dock is available for carry-in, non-motorized boats such as rowboats, canoes, kayaks and paddleboards. Herrick Creek Loop is a 1-mile loop trail that is primarily used for hiking, walking, and nature trips. Besides recreation, the area is used as a living laboratory for research and as an interdisciplinary outdoor classroom for faculty and students in visual arts, communication studies, ecology, engineering, forestry and natural resources, landscape architecture, and other fields. | https://en.wikipedia.org/wiki?curid=378232 | 347,384 |
1,060,056 | The Mint prepared pattern coins with a much smaller eagle in 1858, which struck well, but which officials disliked. Snowden directed Longacre to prepare various patterns that he could select from for a new piece to replace the Flying Eagle cent as of January 1, 1859. The Mint produced between 60 and 100 sets of twelve patterns showing various designs; these were circulated to officials and also were quietly sold by the Mint over the next several years. Longacre's design showing Liberty wearing an Indian-style headress was adopted, with a wreath with lower relief for the reverse of the Indian Head cent, solving the metal flow issues. On November 4, 1858, Snowden wrote to the Treasury Department, stating that the Flying Eagle cent had proved "not very acceptable to the general population" as they felt the bird was not true to life, and that the Native American design would "giv[e] it the character of America". | https://en.wikipedia.org/wiki?curid=3342184 | 1,059,505 |
25,268 | Programming languages differ from most other forms of human expression in that they require a greater degree of precision and completeness. When using a natural language to communicate with other people, human authors and speakers can be ambiguous and make small errors, and still expect their intent to be understood. However, figuratively speaking, computers "do exactly what they are told to do", and cannot "understand" what code the programmer intended to write. The combination of the language definition, a program, and the program's inputs must fully specify the external behavior that occurs when the program is executed, within the domain of control of that program. On the other hand, ideas about an algorithm can be communicated to humans without the precision required for execution by using pseudocode, which interleaves natural language with code written in a programming language. | https://en.wikipedia.org/wiki?curid=23015 | 25,259 |
151,726 | On 27 April 2013, Steck was climbing on the Lhotse Face, above Camp 3 of the Southeast Ridge route of Mount Everest. He was climbing with Simone Moro and Jonathan Griffith when they passed a group of 17 Sherpa climbers who were fixing rope for the rest of the teams on the mountain. There are conflicting accounts from both parties, with the Sherpa claiming that Moro and his team insulted them and knocked over ice while traversing above them. To ease the situation, Moro and his teammates descended to Camp 2. While discussing the incident with other climbers, Steck, Moro and Griffith claim they were violently attacked by a much larger group of Sherpa. They claim the Sherpa had covered their faces as they threw punches and rocks at them. The Sherpas not only deny the numbers claimed to be involved in the fight, but claim that the altercation was initiated by Martin Schmidt, who was falsely claiming to be Simone Moro, another climber on Steck's expedition team who was also involved in the earlier dispute. Tensions only eased after other foreign climbers at Camp 2, including Melissa Arnot, intervened to defuse the situation. Steck and his team left the mountain but the incident received worldwide attention, allowing Steck and his team to spread their version of events months before any Sherpas were even interviewed about the situation. | https://en.wikipedia.org/wiki?curid=28873789 | 151,658 |
304,718 | During the early 20th century, before the development and availability of coated arc welding electrodes in the late 1920s that were capable of making sound welds in steel, oxy-acetylene welding was the only process capable of making welds of exceptionally high quality in virtually all metals in commercial use at the time. These included not only carbon steel but also alloy steels, cast iron, aluminium, and magnesium. In recent decades it has been superseded in almost all industrial uses by various arc welding methods offering greater speed and, in the case of gas tungsten arc welding, the capability of welding very reactive metals such as titanium. Oxy-acetylene welding is still used for metal-based artwork and in smaller home-based shops, as well as situations where accessing electricity (e.g., via an extension cord or portable generator) would present difficulties. The oxy-acetylene (and other oxy-fuel gas mixtures) welding torch remains a mainstay heat source for manual brazing and braze welding, as well as metal forming, preparation, and localized heat treating. In addition, oxy-fuel cutting is still widely used, both in heavy industry and light industrial and repair operations. | https://en.wikipedia.org/wiki?curid=12414930 | 304,556 |
549,820 | Neutral density (ND) filters have a constant attenuation across the range of visible wavelengths, and are used to reduce the intensity of light by reflecting or absorbing a portion of it. They are specified by the optical density (OD) of the filter, which is the negative of the common logarithm of the transmission coefficient. They are useful for making photographic exposures longer. A practical example is making a waterfall look blurry when it is photographed in bright light. Alternatively, the photographer might want to use a larger aperture (so as to limit the depth of field); adding an ND filter permits this. ND filters can be reflective (in which case they look like partially reflective mirrors) or absorptive (appearing grey or black). | https://en.wikipedia.org/wiki?curid=741823 | 549,532 |
562,289 | When German children from forest kindergartens went to primary school, teachers observed a significant improvement in reading, writing, mathematics, social interactions and many other areas. A yearlong study was done where a group of 9th and 12th grade students learned through outdoor education. The focus was on raising the critical thinking skills of the students as a measure of improvement, where critical thinking was defined to be, "the process of purposeful self-regulatory judgment and decision making". The problem solving capabilities included the ability of students to interpret, to analyze, to evaluate, to infer, to explain and to self-regulate. Researchers found that both 9th and 12th graders scored higher than the control groups in critical thinking by a significant amount. | https://en.wikipedia.org/wiki?curid=2515017 | 562,000 |
1,287,850 | Uniformitarianism held the field against the competitor theories of Neptunism and catastrophism, which partook of Romantic science and theological cosmogony; it established itself as the successor of Plutonism, and became the foundation of modern geology. Its tenets were correspondingly firmly held. Charles Lyell put forward at one point views on what were called "uniformity of kind" and "uniformity of degree" that were incompatible with what was argued later. Lyell's theory, in fact, was of a "steady state" geology, which he deduced from his principles. This went too far in restricting actual geological processes, to a predictable closed system, if it ruled out ice ages (see ice ages#Causes of ice ages), as became clearer not long after Lyell's "Principles of Geology" appeared (1830–3). Of Lubbock's three types of change, the geographical included the theory of migration over land bridges in biogeography, which in general acted as an explanatory stopgap, rather than in most cases being one supported by science. Sea level changes were easier to justify. | https://en.wikipedia.org/wiki?curid=33809974 | 1,287,149 |
560,433 | Photosensitizers have existed within natural systems for as long as chlorophyll and other light sensitive molecules have been a part of plant life, but studies of photosensitizers began as early as the 1900s, where scientists observed photosensitization in biological substrates and in the treatment of cancer. Mechanistic studies related to photosensitizers began with scientists analyzing the results of chemical reactions where photosensitizers photo-oxidized molecular oxygen into peroxide species. The results were understood by calculating quantum efficiencies and fluorescent yields at varying wavelengths of light and comparing these results with the yield of reactive oxygen species. However, it was not until the 1960s that the electron donating mechanism was confirmed through various spectroscopic methods including reaction-intermediate studies and luminescence studies. | https://en.wikipedia.org/wiki?curid=2825553 | 560,144 |
1,376,359 | Ph.D. candidates in the department conduct independent research under supervision of a faculty member. After completing a series of introductory-level courses, graduate students specialize in at least two special or advanced topics within the discipline. Notably, students must demonstrate proficiency in one foreign language (French, German, or Russian), proving their ability to work with mathematical texts from scholars around the world. Graduate students are offered full tuition and student health plan coverage for all five years of the program. They are also able to apply for additional external funding and/or teach courses as Assistants-in-Instruction (AIs). | https://en.wikipedia.org/wiki?curid=58434209 | 1,375,597 |
1,358,943 | In 2004, World Vision Australia and World Vision Ethiopia initiated a forestry-based carbon sequestration project as a potential means to stimulate community development while engaging in environmental restoration. A partnership with the World Bank, the Humbo Community-based Natural Regeneration Project involved the regeneration of 2,728 hectares of degraded native forests. This brought social, economic and ecological benefits to the participating communities. Within two years, communities were collecting wild fruits, firewood, and fodder, and reported that wildlife had begun to return and erosion and flooding had been reduced. In addition, the communities are now receiving payments for the sale of carbon credits through the Clean Development Mechanism (CDM) of the Kyoto Protocol. | https://en.wikipedia.org/wiki?curid=10432337 | 1,358,192 |
500,256 | Some early SLRs featured a built-in CdS meter, usually on the front left side of the top plate, as in the Minolta SR-7. Other manufacturers, such as Miranda and Nikon introduced a CdS prism which fitted to their interchangeable prism SLR cameras. Nikon's early Photomic finder utilized a cover in front of the cell which was raised and a reading was taken and the photographer would either turn the coupled shutter speed dial and/or the coupled aperture ring to center a galvanometer-based meter needle shown in the viewfinder. The disadvantage of this early Photomic prism finder was that the meter had no ON/OFF switch so the meter was constantly 'ON', thus draining battery power. A later Photomic housing had an ON/OFF switch on the Pentaprism. CdS light meters proved more sensitive to light and thus metering in available light situations was becoming more prominent and useful. Further advances in CdS sensitivity, however, were needed as CdS cells suffered from a 'memory effect'. That is, if exposed to bright sunlight, the cell would require many minutes to return to normal operation and sensitivity. | https://en.wikipedia.org/wiki?curid=3193137 | 499,999 |
437,490 | With the advent of film and graphic animation, the possibility of matching text and motion emerged. Examples of animated letter-forms appeared as early as 1899 in the advertising work of George Melies. Early feature films contained temporal typography, but this was largely static text, presented sequentially and subjected to cinematic transitions. It was not until the 1960s that opening titles began to feature typography that was truly kinetic. Scholars recognize the first feature film to extensively use kinetic typography as Alfred Hitchcock's "North by Northwest" (1959). This film's opening title sequence—created by Saul Bass—contained animated text, featuring credits that "flew" in from off-screen, and finally faded out into the film itself. A similar technique was also employed by Bass in "Psycho" (1960). | https://en.wikipedia.org/wiki?curid=1233314 | 437,276 |
1,713,694 | For its next installation, on the Northern Central line between Baltimore, MD and Harrisburg, PA in 1926 (1927?), the PRR tested another variation of cab signals which dropped the loop signal and switched to 100 Hz for the track signal. The pivotal change was that now it would come on above Restricting merely as a carrier and 1.25 to 3 Hz on-off pulsing of it would be used as a code to convey the aspects. The presence of the carrier alone was not meaningful, no pulsing would still mean a Restricting aspect. This new system allowed four signal aspects: Restricting; Approach; Approach (next signal at) Medium (speed); and Clear. Initially the cab signaling system only acted as a form of automatic train stop where the engineer would have to acknowledge any drop in the cab signal to a more restrictive aspect to prevent the brakes from automatically applying. Later, passenger engines were upgraded with speed control which enforced the rulebook speed associated with each cab signal (Clear = No Restriction, Approach Medium = 45 mph, Approach = 30 mph, Restricting = 20 mph). | https://en.wikipedia.org/wiki?curid=22377127 | 1,712,728 |
115,640 | Since about 1998, beginning with Mac OS 8.6, Apple has included the Dvorak layout. It can be activated with the Keyboard Control Panel and selecting "Dvorak". The setting is applied once the Control Panel is closed out. Apple also includes a Dvorak variant they call "Dvorak – Qwerty ⌘". With this layout, the keyboard temporarily becomes QWERTY when the Command (⌘/Apple) key is held down. By keeping familiar keyboard shortcuts like "close" or "copy" on the same keys as ordinary QWERTY, this lets some people use their well-practiced muscle memory and may make the transition easier. Mac OS and subsequently Mac OS X allow additional "on-the-fly" switching between layouts: a menu-bar icon (by default, a national flag that matches the current language, a 'DV' represents Dvorak and a 'DQ' represents Dvorak – Qwerty ⌘) brings up a drop-down menu, allowing the user to choose the desired layout. Subsequent keystrokes will reflect the choice, which can be reversed the same way. | https://en.wikipedia.org/wiki?curid=26301345 | 115,595 |
1,722,899 | There was now enough new data to justify revising the APG system, and a new classification was issued in 2003. Although this resulted in changes within the orders, it did not affect the relationship between them. Lilioid monocots were discussed but not formally recognized (commelinids, renamed from commelinoids, being the only supraordinal grouping in the monocots to be named) and Petrosaviaceae remained unplaced. The second version of the APG coincided with the third Monocot Conference (2003), the findings from which, using additional molecular markers, helped to resolve some of the remaining questions regarding relationships within this assemblage. Petrosaviaceae was shown to be included in what Chase refers to as "liliids" and placed in order Petrosaviales, while Dioscoreales and Pandanales were demonstrated to be sister clades. Rapid advances in understanding monocot relationships necessitated the release of another revision of the APG classification (2009), which incorporated these advances. Further definition of the relationships between lineages using multiple markers is continuing. | https://en.wikipedia.org/wiki?curid=30176361 | 1,721,929 |
304,556 | When a cell discharges, the lead and diluted acid undergo a chemical reaction that produces lead sulfate and water. When a cell is subsequently charged, the lead sulfate and water are turned back into lead and acid. In all lead–acid battery designs, charging current must be adjusted to match the ability of the battery to absorb the energy. If the charging current is too great, electrolysis will occur, decomposing water into hydrogen and oxygen, in addition to the intended conversion of lead sulfate and water into lead dioxide, lead, and sulfuric acid (the reverse of the discharge process). If these gases are allowed to escape, as in a conventional flooded cell, the battery will need to have water (or electrolyte) added from time to time. In contrast, VRLA batteries retain generated gases within the battery as long as the pressure remains within safe levels. Under normal operating conditions the gases can then recombine within the battery itself, sometimes with the help of a catalyst, and no additional electrolyte is needed. However, if the pressure exceeds safety limits, safety valves open to allow the excess gases to escape, and in doing so regulate the pressure back to safe levels (hence "valve regulated" in "VRLA"). | https://en.wikipedia.org/wiki?curid=5897558 | 304,394 |
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