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A (unit of measurement)
unit of electric current in the Système International d’Unités (SI), used by both scientists and technologists. Since 1948 the ampere has been defined as the constant current which, if maintained in two straight parallel conductors of infinite length of negligible circular cross section and placed one metre apart in a vacuum, would produce between these conductors a force equ...
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A (poem by Zukofsky)
American poet, the founder of Objectivist poetry and author of the massive poem “A.”...
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a (unit of area measurement)
basic unit of area in the metric system, equal to 100 square metres and the equivalent of 0.0247 acre. Its multiple, the hectare (equal to 100 ares), is the principal unit of land measurement for most of the world....
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A band (physiology)
...to be responsible for the movement and force developed during contraction (for the relation of cross bridges to the molecular architecture of thick filaments, see below). In the middle of the A band, where only thick filaments are present, is a region called the H zone; the H zone looks somewhat lighter than the overlap region of the A band. Also in the A band is a narrow, lightly staine...
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A Bing (Chinese composer)
...to be responsible for the movement and force developed during contraction (for the relation of cross bridges to the molecular architecture of thick filaments, see below). In the middle of the A band, where only thick filaments are present, is a region called the H zone; the H zone looks somewhat lighter than the overlap region of the A band. Also in the A band is a narrow, lightly staine...
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“À bout de souffle” (film by Godard [1960])
Godard’s first feature film, À bout de souffle (1959; Breathless), which was produced by François Truffaut, his colleague on the journal Cahiers du cinéma, won the Jean Vigo Prize. It inaugurated a long series of features, all celebrated for the often drastic nonchalance of Godard’s....
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a cappella (vocal music)
(Italian: “in the church style”), performance of a polyphonic (multipart) musical work by unaccompanied voices. Originally referring to sacred choral music, the term now refers to secular music as well....
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A cell (animal anatomy)
...strand, the acoustic sensillum, runs from the centre of the tympanic membrane across the tympanic cavity to a nearby skeletal support. This sensillum has two acoustic sensory receptors, called A cells. From the central end of each A cell, an axon passes within the sensillum to the skeletal support and then in the tympanic nerve to the thoracic ganglia of the moth....
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a contrario (argument)
...are arguments by example, by analogy, by the consequences, a pari (arguing from similar propositions), a fortiori (arguing from an accepted conclusion to an even more evident one), a contrario (arguing from an accepted conclusion to the rejection of its contrary), and the argument of authority. The traditional figures of rhetoric are usually only abridged arguments, as, for...
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A Corja (work by Castelo Branco)
...(1875–77) approach Naturalism, he engaged in a literary quarrel with the emergent Naturalist school and parodied their style and subjects in Eusébio Macário (1879) and A Corja (1880; “The Rabble”). Nevertheless, while continuing to express vehement opposition to Naturalism, he more and more closely assimilated its descriptive objectivity and......
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A current (biology)
Another outward K+ current, occurring with little delay after depolarization, is the A current. IA channels are opened by depolarization following hyperpolarization. By increasing the interval between action potentials, they help a neuron to fire repetitively at low frequencies....
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A/D conversion (technology)
As is noted in Analog-to-digital conversion, voice signals, as well as audio and video signals, are inherently analog in form. In most modern systems these signals are digitized prior to transmission, but in some systems the analog signals are still transmitted directly without converting them to digital form. There are two commonly used methods of modulating analog signals. One technique,......
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A delta fibre (nerve fibre)
...of acute pain noted above is mediated by two types of primary afferent nerve fibres that transmit electrical impulses from the tissues to the spinal cord via the ascending nerve tracts. The A delta fibres are larger and conduct impulses more quickly; therefore, they are associated with the sharp, well-localized pain that first occurs. These fibres are thinly myelinated and are activated......
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a dicto simpliciter ad dictum secundum quid (logic)
...are capable of seeing” is no basis for the conclusion that “blind men are capable of seeing.” This is a special case of the fallacy of secundum quid (more fully: a dicto simpliciter ad dictum secundum quid, which means “from a saying [taken too] simply to a saying according to what [it really is]”—i.e., according to its truth as......
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A/F ratio (automobiles)
Oxygen sensors are employed in industry to monitor and control processing atmospheres and also in automobiles to monitor and control the air-to-fuel (A/F) ratio in the internal combustion engine. A prominent sensor material is zirconia, which, as noted above, can be an excellent high-temperature oxygen conductor if suitably doped with Ca2+ or Y3+. A tube or thimble made of......
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A Fang (ancient palace, China)
...architecture from historical writings and long descriptive poems, fu. This was an era of great palace buildings. The first Ch’in emperor undertook the building of a vast palace, the A-fang or O-pang, whose main hall was intended to accommodate 10,000 guests in its upper story. He also copied the palaces and pavilions of each of the feudal lords he had defeated; these buildings str...
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a fortiori (argument)
...analysis of such arguments would require a whole treatise; the best known, however, are arguments by example, by analogy, by the consequences, a pari (arguing from similar propositions), a fortiori (arguing from an accepted conclusion to an even more evident one), a contrario (arguing from an accepted conclusion to the rejection of its contrary), and the argument of......
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a galletto (art design)
...is often credited to other factories. In the main, Doccia continued, belated by some 30 years, the late Baroque styles of Meissen. Three decorative themes distinguish this Doccia ware: the a galletto design, of Chinese origin, consisting of two fighting cocks; the a tulipano pattern, a central, stylized red tulip with surrounding flowers; and a range of polychrome or......
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A horizon (soil type)
...the soil profile (see the figure). Soil horizons are defined by features that reflect soil-forming processes. For instance, the uppermost soil layer (not including surface litter) is termed the A horizon. This is a weathered layer that contains an accumulation of humus (decomposed, dark-coloured, carbon-rich matter) and microbial biomass that is mixed with small-grained minerals to form......
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“A la orilla de un pozo” (work by Chacel)
...chronologically to the Generation of 1927, including Rosa Chacel, a major essayist, poet, and novelist. Her polished, intellectual verse appeared in A la orilla de un pozo (1936; At the Edge of a Well), a collection of neo-Gongoristic sonnets, and in Versos prohibidos (1978; “Prohibited Verse”), a mixture of unrhymed pieces that resemble in.....
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à la poupée (printing)
There are two ways of making intaglio prints in varied colours. In the method known as à la poupée (French: “with the doll”), a doll-shaped bundle of fabric is used to apply different colours to different areas of a single plate, which is then printed in the usual way. In the other method separate plates, each carrying a different colour, are successively......
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“À la Recherche de Marcel Proust” (work by Maurois)
...Sand (Lélia, 1952), and Honoré de Balzac (Prométhée, 1965; Prometheus, the Life of Balzac). À la Recherche de Marcel Proust (1949; The Quest for Proust) is considered his finest biography....
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“À la recherche du temps perdu” (novel by Proust)
French novelist, author of À la recherche du temps perdu (1913–27; In Search of Lost Time), a seven-volume novel based on Proust’s life told psychologically and allegorically....
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À la recherche d’une musique concrète (book by Schaeffer)
Schaeffer taught electronic composition at the Paris Conservatory from 1968 until 1980. His writings include novels, short stories, and essays, as well as theoretical works in music, such as À la recherche d’une musique concrète (1952; “In Search of a Concrete Music”), Traité des objets musicaux (1966; “Treatise on Musical Objects...
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A la vejez, viruelas (work by Bretón de los Herreros)
...Madrid, where his family moved in 1806, later serving in the army from 1812 to 1822. He held various governmental positions throughout his life and was director of the National Library from 1847. A la vejez, viruelas (“In Old Age, Chickenpox”), his first play, was produced in 1824 and brought him immediate success. Of the almost 180 plays he produced during his lifetime,......
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a lo divino (Spanish literature)
in Spanish literature, the recasting of a secular work as a religious work, or, more generally, a treatment of a secular theme in religious terms through the use of allegory, symbolism, and metaphor. Adaptations a lo divino were popular during the Golden Age of Spanish literature during the 16th and 17th centuries....
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“A l’ombre des jeunes filles en fleurs” (work by Proust)
...Proust now rejected them. Further negotiations in May–September 1916 were successful, and in June 1919 À l’ombre des jeunes filles en fleurs (Within a Budding Grove) was published simultaneously with a reprint of Swann and with Pastiches et mélanges, a miscellaneous volume contain...
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“À nous la liberté!” (film by Clair)
...duplicate or substitute for visual representation but rather as a counterpoint to it. His Sous les toits de Paris, Le Million, and À nous la liberté! constituted homage to the art of silent film and a manifesto for a new cinema. Clair rigorously constructed comical situations using either images or sounds.....
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A, Operation (Japanese strategy)
...to reduce the Mariana Islands, lying 1,000 miles from Enewetak and 3,500 miles from Pearl Harbor. Against this threat, after the destruction at Truk, the Japanese hastily drew up a new defense plan, “Operation A,” relying on their remaining 1,055 land-based aircraft in the Marianas, in the Carolines, and in western New Guinea and on timely and decisive intervention by a sea force,...
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a pari (argument)
...types of association and dissociation. A detailed analysis of such arguments would require a whole treatise; the best known, however, are arguments by example, by analogy, by the consequences, a pari (arguing from similar propositions), a fortiori (arguing from an accepted conclusion to an even more evident one), a contrario (arguing from an accepted conclusion to the......
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a posteriori distribution (probability)
This distribution, derived by using Bayes’s theorem to combine the a priori distribution with the conditional distribution for the outcome of the experiment, is called the a posteriori distribution....
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a posteriori knowledge (philosophy)
knowledge derived from experience, as opposed to a priori knowledge....
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a priori distribution (probability)
...giving the probability f(r) that the number of red balls is in fact r where f(0) +⋯+ f(N) = 1. This distribution is called an a priori distribution because it is specified prior to the experiment of drawing balls from the urn. The binomial distribution is now a conditional probability, given the value of r. Fina...
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a priori knowledge (philosophy)
in Western philosophy since the time of Immanuel Kant, knowledge that is independent of all particular experiences, as opposed to a posteriori knowledge, which derives from experience alone. The Latin phrases a priori (“from what is before”) and a posteriori (“from what is after”) were used in philosophy originally to distinguish...
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A proposition (logic)
A:universal affirmativeAll A’s are B’s....
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“À rebours” (work by Huysmans)
...among themselves. Another significant figure was the novelist Joris-Karl Huysmans, who developed interest in the esoteric and whose À rebours (1884; Against the Grain) was called by Arthur Symons “the breviary of the Decadence.”...
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A ring (astronomy)
...gap in the major rings. Lying between 1.95 and 2.02 Saturn radii and not devoid of particles, the Cassini division exhibits complicated variations in optical depth, with an average value of 0.1. The A ring extends from 2.02 to 2.27 Saturn radii and has optical depths of 0.4 to 1.0. Interior to the B ring lies the third major ring, the C ring (sometimes known as the crepe ring), at 1.23 to 1.52....
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A Silvia (work by Leopardi)
Two experiences in 1817 and 1818 robbed Leopardi of whatever optimism he had left: his frustrated love for his married cousin, Gertrude Cassi (subject of his journal Diario d’amore and the elegy “Il primo amore”), and the death from consumption of Terese Fattorini, young daughter of his father’s coachman, subject of one of his greatest lyrics, “A Silvia....
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A site (biochemistry)
...base triplets in mRNA; the base triplets in mRNA specify the amino acids to be added to the protein chain. During or shortly after the pairing occurs the aminoacyl–tRNA moves from the aminoacyl-acceptor (A) site on the ribosome to another site, called a peptidyl-donor (P) site....
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A Star Is Born (film by Pierson [1976])
...for The OmenOriginal Score and Its Adaptation or Adaptation Score: Leonard Rosenman for Bound For GloryOriginal Song: “Evergreen (Love Theme from A Star Is Born)” from A Star Is Born; music by Barbra Streisand, lyrics by Paul Williams...
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À travers les vents (poetry by Choquette)
Choquette moved to Montreal at age eight. His first collection of poetry, À travers les vents (1925; “Through the Winds”), won him a reputation based on his disregard of syntax and his freedom of expression. For this volume, Choquette received the Prix David in 1926; his collection of poetry Metropolitan Museum (1930) won it......
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a tulipano (art design)
...by some 30 years, the late Baroque styles of Meissen. Three decorative themes distinguish this Doccia ware: the a galletto design, of Chinese origin, consisting of two fighting cocks; the a tulipano pattern, a central, stylized red tulip with surrounding flowers; and a range of polychrome or white-figured reliefs of mythological subjects often erroneously named Capodimonte and......
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A&M Records (American company)
...in December 1976, the group became a national sensation. Scandalized in the tabloid press, the Sex Pistols were dropped by their first record company, EMI, in January 1977; their next contract, with A&M Records, was severed after only a few days in March....
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A&P (American company)
German-owned food distribution company that operates supermarket chains in the United States and Canada. Headquarters are in Montvale, New Jersey....
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A-1 (aircraft)
...A-20 Havoc, which were armed with 20-millimetre cannons and .30- or .50-inch machine guns. Two other American attack aircraft of the 1940s and ’50s were the Douglas B-26 Invader and the Douglas A-1 Skyraider. All of these types were piston-engined, propeller-driven aircraft....
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A-1 (missile)
After four years of research and development, the U.S. Navy in 1960 began to deploy nuclear-powered submarines armed with 16 Polaris missiles each. Each missile was 31 feet (9.4 m) long and 4.5 feet (1.4 m) in diameter and was powered by two solid-fueled stages. Three models were developed: the A-1, with a range of 1,400 miles (2,200 km) and a one-megaton nuclear warhead; the A-2, with a......
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A-10A (aircraft)
...the Grumman A-6 Intruder, first flown in 1960; the U.S. Navy’s McDonnell Douglas A-4 Skyhawk, first flown in 1954; and the Ling-Temco-Vought A-7 Corsair, first flown in 1965. The Fairchild Republic A-10A Thunderbolt II, a two-seat, twin-engine aircraft first flown in 1972, became in the mid-1970s the principal close-support attack aircraft of the U.S. Air Force. Its primary armament is a...
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A-2 (missile)
...long and 4.5 feet (1.4 m) in diameter and was powered by two solid-fueled stages. Three models were developed: the A-1, with a range of 1,400 miles (2,200 km) and a one-megaton nuclear warhead; the A-2, with a 1,700-mile (2,700-kilometre) range and a one-megaton warhead; and the A-3, capable of delivering three 200-kiloton warheads a distance of 2,800 miles (4,500 km)....
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A-20 (aircraft)
...monoplanes could endure heavy antiaircraft fire while attacking tanks and troop columns at very close range. The most important types were the Soviet Ilyushin Il-2 Stormovik and the U.S. Douglas A-20 Havoc, which were armed with 20-millimetre cannons and .30- or .50-inch machine guns. Two other American attack aircraft of the 1940s and ’50s were the Douglas B-26 Invader and the Douglas A...
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A-3 (missile)
...Three models were developed: the A-1, with a range of 1,400 miles (2,200 km) and a one-megaton nuclear warhead; the A-2, with a 1,700-mile (2,700-kilometre) range and a one-megaton warhead; and the A-3, capable of delivering three 200-kiloton warheads a distance of 2,800 miles (4,500 km)....
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A-3TK (missile)
Between 1971 and 1978 the Polaris was replaced by the Poseidon missile in the U.S. SLBM force. The United Kingdom, after adopting the A-3 in 1969, refined it into the A-3TK, or Chevaline, system, which was fitted with such devices as decoy warheads and electronic jammers for penetrating Soviet ballistic-missile defenses around Moscow. In 1980 the United Kingdom announced plans to replace its......
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A-4 (airplane)
After World War II, faster jet aircraft were developed for attack missions. Among the U.S. types were the Grumman A-6 Intruder, first flown in 1960; the U.S. Navy’s McDonnell Douglas A-4 Skyhawk, first flown in 1954; and the Ling-Temco-Vought A-7 Corsair, first flown in 1965. The Fairchild Republic A-10A Thunderbolt II, a two-seat, twin-engine aircraft first flown in 1972, became in the......
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A-4 (military technology)
German ballistic missile of World War II, the forerunner of modern space rockets and long-range missiles....
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A-6 Intruder (aircraft)
After World War II, faster jet aircraft were developed for attack missions. Among the U.S. types were the Grumman A-6 Intruder, first flown in 1960; the U.S. Navy’s McDonnell Douglas A-4 Skyhawk, first flown in 1954; and the Ling-Temco-Vought A-7 Corsair, first flown in 1965. The Fairchild Republic A-10A Thunderbolt II, a two-seat, twin-engine aircraft first flown in 1972, became in the......
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A-7 (aircraft)
...developed for attack missions. Among the U.S. types were the Grumman A-6 Intruder, first flown in 1960; the U.S. Navy’s McDonnell Douglas A-4 Skyhawk, first flown in 1954; and the Ling-Temco-Vought A-7 Corsair, first flown in 1965. The Fairchild Republic A-10A Thunderbolt II, a two-seat, twin-engine aircraft first flown in 1972, became in the mid-1970s the principal close-support attack....
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a-ak (East Asian music)
ancient court music. The name is a Japanese pronunciation of the Chinese characters for elegant music (ya yueh). Such music first appeared in Japan as an import from Korea in the 5th century and had become an established court tradition by the 8th century. The various forms of North Asian, Chinese, Indian, Southeast Asian, and indigenous Japanese music were organized in t...
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a-che-lha-mo (Buddhist play)
...or to the netherworld when playing the role of a psychopomp, or conductor of souls. Performances of the Buddhist monastic dance, known as ’cham, and the Buddhist morality plays, called a-che-lha-mo (“older sister goddess”), were accompanied by a variety of instruments, especially drums and horns. There were large and small drums, short horns with fingering hol...
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A-ch’eng (China)
former city, central Heilongjiang sheng (province), far northeastern China. In 2006 it was incorporated into the city of Harbin, and it became a southeastern district of that city....
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A-DNA (chemical compound)
Several structural variants of DNA are known. In A-DNA, which forms under conditions of high salt concentration and minimal water, the base pairs are tilted and displaced toward the minor groove. Left-handed Z-DNA forms most readily in strands that contain sequences with alternating purines and pyrimidines. DNA can form triple helices when two strands containing runs of pyrimidines interact......
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A-effect (theatre)
idea central to the dramatic theory of the German dramatist-director Bertolt Brecht. It involves the use of techniques designed to distance the audience from emotional involvement in the play through jolting reminders of the artificiality of the theatrical performance....
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A-erh-chin Shan (mountains, China)
mountain range in the southern part of the Uygur Autonomous Region of Xinjiang, northwestern China. Branching off from the Kunlun Mountains, the range runs for more than 400 miles (650 km) from southwest to northeast to form the boundary between the Tarim Basin to the north and the minor basin of Lake Ayakekumu (Ayakkum) and the Qai...
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A-erh-ko Shan (mountains, China)
one of the complex mountain chains that form the Kunlun Mountains in western China. The Arkatag range is in the east-central portion of the Kunluns. Mount Muztag (Muztagh), at its western end, reaches an elevation of 25,338 feet (7,723 metres) and is the tallest peak in both the Arkatag and the Kunlun ranges; Bukadaban Peak, at the eastern end, is 22,507 feet ...
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A-erh-t’ai Shan (mountain range, Asia)
complex mountain system of Central Asia extending approximately 1,200 miles (2,000 km) in a southeast-northwest direction from the Gobi (Desert) to the West Siberian Plain, through China, Mongolia, Russia, and Kazakhstan. The jagged mountain ridges derive their name ...
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A-frame level (tool)
The tool for determining horizontal direction is called a level. The Egyptians used an A-frame, on which a plumb line was suspended from the vertex of the A. When the feet of the A were set on the surface to be checked, if the plumb line bisected the crossbar of the A, the surface was horizontal. The A-frame level was used in Europe until the middle of the 19th century. Sometimes a variation is......
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A-Group culture (ancient people)
The region of Lower Nubia, between the first and second Nile cataracts, saw one of the earliest phases of state formation in the world when rulers of the A-Group culture, who were buried in a cemetery at Qustul excavated by the Oriental Institute of the University of Chicago in the 1960s, adopted symbols of kingship similar to those of contemporary kings of Egypt of the Naqādah......
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A-Hmao (people)
...the official Chinese term for four distinct groups of people who are only distantly related through language or culture: the Hmu people of southeast Guizhou, the Qo Xiong people of west Hunan, the A-Hmao people of Yunnan, and the Hmong people of Guizhou, Sichuan, Guangxi, and Yunnan (see China: People). There are some nine million Miao in China, of whom the Hmong constitute probably......
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A-Hmao language
Two original writing systems developed for the Hmong language have enjoyed some success. Between 1904 and 1936 the missionary Samuel Pollard invented the Pollard script for writing A-Hmao, a Hmongic language spoken in northeast Yunnan and northwest Guizhou provinces. The Pollard system uses primary symbols to represent consonants and smaller secondary symbols to represent vowels. The placement......
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A-kuei (Chinese general and official)
general and official during the middle years of the Qing dynasty. The scion of a noble family, Agui directed Chinese military expeditions that quelled uprisings in the western provinces of Sichuan and Gansu. He also conquered Ili and Chinese Turkistan, areas on China’s northwestern frontier that are today part of the Uygur Autonomous Region of Xinjiang. In addition, he he...
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A-la-shan Kao-yüan (desert region, China)
southernmost portion of the Gobi (desert), occupying about 400,000 square miles (1,000,000 square km) in north-central China. Covering the western portions of the Inner Mongolia Autonomous Region and the northern part of Gansu province, it is bounded by the Huang He (Yellow River) and Helan Mountains on ...
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A-la-shan-yu Ch’i (banner, China)
The area within Kansu’s jursidiction has undergone several changes since 1950. In 1954 Kansu annexed the province of Ningsia. In 1956 the A-la-shan-yu Ch’i and O-chi-na Ch’i banners in northwestern Kansu were detached and incorporated into the Inner Mongolia Autonomous Region. In 1958 the affixed Ningsia Province was separated from Kansu to become the Hui Autonomous Region of ...
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A-ling Mountains (mountains, China)
mountain range forming the eastern section of a mountain system in the southern part of the Tibet Autonomous Region, southwestern China. In the west the system comprises a northern range, the Nganglong (A-ling) Mountains, and a southern range, the Kailas Range, which is much more rugged and heavily glaciated. The highest peak of the Nganglong Mountains is 21,637 feet (6,595 metres) above sea......
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A-lo-pen (Persian bishop)
According to the inscription, the Chinese emperor Taizong received the Nestorian Persian monk A-lo-pen in his capital city of Chang’an (modern Xi’an) in 625 and looked with favour upon him and the writings of the “luminous doctrine” (Christianity) he brought with him. By 638 a monastery for this monk and 20 others had been constructed at the expense of the Imperial coff...
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A-mdo (region, China)
one of three historical regions of Central Asia (the other two being Dbus-Gtsang and Khams) into which Tibet was once divided....
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A–N transmitting station (aerial navigation)
...a system of radio transmitting stations, each of which transmits a signal that not only carries identification but also is of intrinsic value to a navigator in fixing his position. The older “A–N” type, dating from 1927, operates at low and medium frequencies. The only equipment needed in the aircraft is an ordinary radio receiver. Each station......
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A-pao-chi (emperor of Liao dynasty)
leader of the nomadic Mongol-speaking Khitan tribes who occupied the northern border of China....
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“A-p’i-ta-mo chü-she lun” (work by Vasubandhu)
encyclopaedic compendium of Abhidharma (scholasticism)....
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“A-Q zhengzhuan” (work by Lu Xun)
...acerbic, somewhat westernized, and often satirical attacks on China’s feudalistic traditions established him as China’s foremost critic and writer. His “Ah Q cheng-chuan” (1921; “The True Story of Ah Q”), a damning critique of early 20th-century conservatism in China, is the representative work of the May Fourth period and has become an international cl...
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A-Rod (American baseball player)
American professional baseball player, who was a noted power hitter. In 2007 he became the youngest player in major league history to hit 500 career home runs....
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A-scan (ultrasonography)
...the internal organs. In the B-scan mode, a linear array of transducers is used to scan a plane in the body, and the resultant data is displayed on a television screen as a two-dimensional plot. The A-scan technique uses a single transducer to scan along a line in the body, and the echoes are plotted as a function of time. This technique is used for measuring the distances or sizes of internal.....
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A-type star (astronomy)
...lines of ionized helium appear in the spectra. Class B stars typically range from 10,000 K to 25,000 K and are also bluish white but show neutral helium lines. The surface temperatures of A-type stars range from 7,400 K to about 10,000 K; lines of hydrogen are prominent, and these stars are white. F-type stars are yellow-white, reach 6,000–7,400 K, and display many spectral......
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A-V node (anatomy)
...of both atria to trigger the contraction of those two chambers, which forces blood into the ventricles. The wave of atrial electrical activity activates a second patch of conductive tissue, the atrioventricular node, initiating a second discharge along an assembly of conductive fibres called the bundle of His, which induces the contraction of the ventricles. When electrical conduction......
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A. Philip Randolph Institute (American organization)
...of both atria to trigger the contraction of those two chambers, which forces blood into the ventricles. The wave of atrial electrical activity activates a second patch of conductive tissue, the atrioventricular node, initiating a second discharge along an assembly of conductive fibres called the bundle of His, which induces the contraction of the ventricles. When electrical conduction.........
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A.B. (degree)
...four years. The master’s degree involves one to two years’ additional study, while the doctorate usually involves a lengthier period of work. British and American universities customarily grant the bachelor’s as the first degree in arts or sciences. After one or two more years of coursework, the second degree, M.A. or M.S., may be obtained by examination or the completion o...
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A.C. Nielsen Company (American company)
...interests at an early age. In 1918 he graduated from the University of Wisconsin and then worked briefly as an engineer. In 1923, with the financial backing of his fraternity brothers, he founded A.C. Nielsen Co., which eventually became the largest market-research concern in the world. In the early years the company had difficulties, almost going bankrupt twice, but it finally established a......
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A.C.T. (territory, Australia)
political entity of the Commonwealth of Australia consisting of Canberra, the national capital, and surrounding land. Most of the Australian Capital Territory lies within the Southern Tablelands district of New South Wales in southeastern Australia, but there is also an area of some 28 square miles (73 square km) to the east on the ...
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A.M. (Dutch translator)
...taken from the Latin-English dictionary by Thomas Thomas, Dictionarium linguae Latinae et Anglicanae (1588). But the third source is most remarkable. In 1599 a Dutchman known only as A.M. translated from Latin into English a famous medical work by Oswald Gabelkhouer, The Boock of Physicke, published at Dort, in the Netherlands. As he had been away from England for......
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A.M. (degree)
...a lengthier period of work. British and American universities customarily grant the bachelor’s as the first degree in arts or sciences. After one or two more years of coursework, the second degree, M.A. or M.S., may be obtained by examination or the completion of a piece of research. At the universities of Oxford and Cambridge, holders of a B.A. can receive an M.A. six or seven years aft...
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A.O. Barnabooth: His Diary (work by Larbaud)
Valery Larbaud’s A.O. Barnabooth: son journal intime (1913; A.O. Barnabooth: His Diary) depicts the slow discovery of the self after an initial liberation. An enormously successful exercise in nostalgia, Le Grand Meaulnes (1913; Le Grand Meaulnes: The Land of Lost Content) by Alain-Fournier.....
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“A.O. Barnabooth: son journal intime” (work by Larbaud)
Valery Larbaud’s A.O. Barnabooth: son journal intime (1913; A.O. Barnabooth: His Diary) depicts the slow discovery of the self after an initial liberation. An enormously successful exercise in nostalgia, Le Grand Meaulnes (1913; Le Grand Meaulnes: The Land of Lost Content) by Alain-Fournier.....
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A.O. Smith Research Building (building, Milwaukee, Wisconsin, United States)
...all-glass curtain wall, which was only on a single street facade, was that of the Hallidie Building (1918) in San Francisco. The first multistory structure with a full glass curtain wall was the A.O. Smith Research Building (1928) in Milwaukee by Holabird and Root; in it the glass was held by aluminum frames, an early use of this metal in buildings. But these were rare examples, and it was......
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A.S. Abell Company (American company)
...Sun papers have always provided outstanding war coverage, particularly in World War II. The Sun newspapers, together with their corporate owner, the A.S. Abell Company, were bought by the Times Mirror Company in 1986. In 2000 the Times Mirror merged with the Tribune Company, and The Baltimore Sun thereby became a......
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A.V. Roe and Company, Ltd. (British company)
Roe founded A.V. Roe and Company, Ltd., with his brother Humphrey in 1910. Of his early planes, the Avro 504 was the most successful: more than 17,000 were manufactured. It was used on bombing missions in the early part of World War I and served as a trainer for British pilots. Ten years after the war, Roe severed all ties with his company and acquired an interest in another firm, which became......
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A300 (aircraft)
The A300 was developed to fill the market niche for a short- to medium-range, high-capacity aircraft. It was the first wide-body jetliner to be equipped with only two engines for better operating economics. The A300 prototype made its first flight in 1972, and the aircraft entered commercial service with Air France in 1974. Despite its excellent performance, the A300 initially sold poorly......
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A300-600ST (aircraft)
...companies are responsible for about a third of Airbus components. The partner companies perform much of the subassembly in their own factories. A fleet of special transport aircraft (the Airbus Super Transporter Beluga, based on the A300-600 passenger aircraft) is used to airlift the subassemblies to one of two final assembly lines in France and Germany. The Airbus A300/A310 and A330/A340......
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A310 (aircraft)
...Lines entered into a leasing arrangement for the aircraft. A second boost for Airbus came in 1978, when it launched a program to develop a smaller-capacity, medium-range plane. That aircraft, the A310, first flew in 1982 and entered service three years later. With the addition of the A310 to its product line, Airbus Industrie was able to offer to operators the advantages and savings of an......
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A320 (aircraft)
...a two-pilot cockpit (in which the duties of a third crew member, the flight engineer, were performed by computers) and extensive use of composite materials for the airframe. Its third product, the A320 (1988), was the first subsonic commercial aircraft to be designed with fly-by-wire (electric rather than mechanical) primary controls and the first commercial aircraft to feature the so-called......
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A380 (aircraft)
...Corporate Jetliner, based on the A319 aircraft. Two years later Airbus Military Company was formed as a sudsidiary to develop a military transport, named the A400M. In 2007 Airbus launched the A380, the world’s largest airliner, with a standard seating of 555 and a maximum capacity of 853 in an all-economy class configuration....
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AA (organization)
voluntary fellowship of alcoholic persons who seek to get sober and remain sober through self-help and the help of other recovered alcoholics. Although general conventions meet periodically and Alcoholics Anonymous World Services, Inc., is headquartered in New York City, all AA groups are essentially local and autonomous. To counteract self-indulgence and promote the group’s welfare, member...
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AA (British organization)
...Switzerland, for example, developed a form, the triptyque, that exempted motorists from paying customs duties on their autos when crossing national borders. Britain’s Royal Automobile Club (RAC) and Automobile Association (AA) pioneered nationwide patrols, first by bicycle and later on motorbikes. The first roadside telephone box for motorist assistance was installed by the RAC in 1919. ...
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a’a (lava flow)
Mafic (ferromagnesian, dark-coloured) lavas such as basalt characteristically form flows known by the Hawaiian names pahoehoe and aa (or a’a). Pahoehoe lava flows are characterized by smooth, gently undulating, or broadly hummocky surfaces. The liquid lava flowing beneath a thin, still-plastic crust drags and wrinkles it into tapestry-like folds and ro...
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