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Altenburg ... Altman, Sidney

Altenburg: city, Thuringia Land (state), central Germany. It lies along the Pleisse River, at the southern edge of the central German brown-coal deposits, south of Leipzig. First mentioned in 976 as the site of a watchtower near an old Slav fortress, it was a trading centre and royal residence in the ...
Altenkirch, E.: (from the article "thermoelectric power generator") Systematic study began on thermoelectricity between about 1885 and 1910. By 1910 Edmund Altenkirch, a German scientist, satisfactorily calculated the potential efficiency of thermoelectric generators and delineated the parameters of the materials needed to build practical devices. Unfortunately, metallic conductors were the only materials available at the time, rendering it ...
altepetl: (from the article "Latin America, history of") ...with the Spaniards or the conquest, which seemed to them at first much like earlier conquests; they remained preoccupied to a large extent with their internal rivalries. The local state, the altepetl, with its rotating constituent parts, remained viable as a functioning autonomous unit and as bearer of all major ...
alter ego: (from the article "myth") Other religious and folkloric traditions view the life of man as bound up with that of a plant or animal: if one is destroyed the other dies as well. In some traditions, this is confined to the familiar or guardian of a witch or shaman; in others, it is an ...
alteration pseudomorph: (from the article "pseudomorph") Pseudomorphs are formed by substitution, deposition, or alteration. In the formation of a pseudomorph by substitution, the original substance has been gradually removed and simultaneously replaced by another. A common example of this is petrified wood, in which all the cellulose fibres have been replaced by silica, even those in ...
Alternanthera: (from the article "Amaranthaceae") ...flower; and the fruit may be a capsule, utricle, nutlet, drupe, or berry. Species of globe amaranth (Gomphrena) and cockscomb (Celosia) are cultivated as ornamentals; the genera Alternanthera and Iresine each have several species that are cultivated as bedding plants for their attractive and colourful leaves. The genus Amaranthus contains ...
alternate binaural loudness balance test: (from the article "ear, human") ...be as loud as they are to a healthy ear. This rapid increase in loudness above the threshold level is called recruitment. When the opposite ear has normal hearing, recruitment can be measured by the alternate binaural loudness balance test. The subject is asked to set the controls so that ...
alternate leaf arrangement: (from the article "angiosperm") The three patterns of leaf arrangement on stems in angiosperms are alternate, opposite (paired), and whorled. In alternate-leaved plants, the leaves are single at each node and borne along the stem alternately in an ascending spiral. In opposite-leaved plants, the leaves are paired at a node and borne opposite to ...
alternating current: flow of electric charge that periodically reverses; it starts, say, from zero, grows to a maximum, decreases to zero, reverses, reaches a maximum in the opposite direction, returns again to the original value, and repeats this cycle indefinitely. The interval of time between the attainment of a definite value on ... [22 Related Articles]
alternating electric field: (from the article "particle accelerator") ...is, change direction-at a frequency of at least 100 million cycles per second, or 100 megahertz (MHz). Both linear and cyclic accelerators generally accelerate particles by using the alternating electric fields present in electromagnetic waves, typically at frequencies from 100 to 3,000 MHz-that is, ranging from radiowaves to microwaves.
alternating-current circuit: (from the article "electricity") Certain circuits include sources of alternating electromotive forces of the sinusoidal form V = V₀ cos(omegat) or V = V₀ sin(omegat). The sine and cosine functions have values that vary between +1 and −1; either of the equations for the voltage represents a potential that varies with respect to time ...
alternating-current commutator motor: (from the article "electric motor") A specially designed series-commutator motor may be operated from a single-phase alternating voltage supply. When the supply current reverses, both the magnetic field and the armature current are reversed. Thus, the torque remains in the same direction. These motors are often called universal motors because they may be used with ...
alternating-current generator: (from the article "automobile") The source of energy for the various electrical devices of the automobile is a generator, or alternator, that is belt-driven from the engine crankshaft. The design is usually an alternating-current type with built-in rectifiers and a voltage regulator to match the generator output to the electric load and also to ...
alternating-current motor: (from the article "locomotive") The potential advantages of using alternating instead of direct current prompted early experiments and applications of this system. With alternating current, especially with relatively high overhead-wire voltages (10,000 volts or above), fewer substations are required, and the lighter overhead current supply wire that can be used correspondingly reduces the weight ...
alternating-current transmission: (from the article "ship") Direct-current transmission is occasionally used because it allows propeller speed and engine speed to be completely independent. Alternating-current transmission with synchronous propulsion motors also is used, usually in high-powered propulsion plants because it avoids the commutation problems that handicap high-power direct-current machinery. Exact electrical synchronization of motor speed...
alternating-gradient focusing: (from the article "particle accelerator") Strong focusing was first applied to the electron synchrotron in the 1.2-GeV device built in 1954 at Cornell University in Ithaca, N.Y. All large electron synchrotrons now are equipped with linear accelerators as injectors. The practical limit on the energy of an electron synchrotron is set by the cost of ...
alternation of generations: in biology, the alternation of a sexual phase and an asexual phase in the life cycle of an organism. The two phases, or generations, are often morphologically, and sometimes chromosomally, distinct. [11 Related Articles]
alternative hypothesis: (from the article "statistics") ...probability distribution. First, a tentative assumption is made about the parameter or distribution. This assumption is called the null hypothesis and is denoted by H₀. An alternative hypothesis (denoted H_a), which is the opposite of what is stated in the null hypothesis, is then defined. The hypothesis-testing procedure involves using ...
Alternative Medicine: Alternative and complementary medicine covers a broad range of healing philosophies, approaches, and therapies. The Office of Alternative Medicine (OAM) at the U.S. National Institutes of Health (NIH) defines alternative and complementary medicine as "those treatments and health care practices not taught widely in medical schools, not generally used in ...
Alternative Minimum Tax: (from the article "United States") ...President Bush complained that a massive spending bill at year's end contained more than 9,800 such additions, with an estimated cost of $10 billion. Congress also provided a one-year fix for the Alternative Minimum Tax (AMT), a 1978 law originally written to ensure that the wealthy paid at least minimal ...
alternative pathway: (from the article "complement") Complement activation occurs by two routes, called the classical pathway and the alternative pathway, or properdin system. A different type of signal activates each pathway. The classical pathway is triggered by groups of antibodies bound to the surfaces of a microorganism, while the alternative pathway is spurred into action by ...
alternative rock: pop music style, built on distorted guitars and rooted in generational discontent, that dominated and changed rock between 1991 and 1996. It burst into the mainstream when "Smells Like Teen Spirit"-the first major-label single from Nirvana, a trio based in Seattle, Washington, U.S.-became a national hit. Suddenly, older, difficult, and ... [5 Related Articles]
Alternative Sports: In the 1990s so-called alternative sports made inroads into the imagination and recreation time of people around the world--but especially in the United States. Figures from the National Sporting Goods Association showed a decline in participation by Americans in traditional sports, including football and baseball, in favour of such new ... [1 Related Articles]
Alternative Sports: In the 1990s so-called alternative sports made inroads into the imagination and recreation time of people around the world--but especially in the United States. Figures from the National Sporting Goods Association showed a decline in participation by Americans in traditional sports, including football and baseball, in favour of such new ...
Alternative Sports: In the 1990s so-called alternative sports made inroads into the imagination and recreation time of people around the world--but especially in the United States. Figures from the National Sporting Goods Association showed a decline in participation by Americans in traditional sports, including football and baseball, in favour of such new ... [3 Related Articles]
Alternative Sports: In the 1990s so-called alternative sports made inroads into the imagination and recreation time of people around the world--but especially in the United States. Figures from the National Sporting Goods Association showed a decline in participation by Americans in traditional sports, including football and baseball, in favour of such new ...
alternative-fuel vehicle: (from the article "automobile") Alternative-fuel vehicles
Altertumswissenschaft: (from the article "classical scholarship") ...result of abbreviating the 19th-century "comparative philology"-has lent an unfortunate ambiguity to the term. During the 19th century, Germans evolved the concept of Altertumswissenschaft ("science of antiquity") to emphasize the unity of the various disciplines of which the study of the ancient world consists. Broadly speaking, the province of...
Altgeld, John Peter: reformist Democratic governor of Illinois (1893-97) known principally for his pardon (June 26, 1893) of German-American anarchists involved in the Haymarket Riot, a labour protest meeting in which seven Chicago policemen were killed at Haymarket Square on May 4, 1886. [2 Related Articles]
Althamer, Pawel: (from the article "Art and Art Exhibitions") ...literally, in 1:4 scale-by Dominique Gonzalez-Foerster of selected works from the past three Sculpture Projects exhibitions. The notion of sculpture was interpreted very broadly in the work of Pawel Althamer, who cut a path nearly 1 km (0.6 mi) long through meadows and fields on the outskirts of the town; ...
Althiburos: ancient city of Numidia in North Africa, on the road constructed by the Roman emperor Hadrian in AD 123, between Carthage and Theveste (Tabassah) in what is now Tunisia. The town, originally an indigenous settlement, obtained municipal rights from Hadrian.
Althing: (from the article "democracy") ...and Denmark regional assemblies developed. In 930 Viking descendants in Iceland created the first example of what today would be called a national assembly, legislature, or parliament-the Althing (see thing). In later centuries, representative institutions also were established in the emerging nation-states of Norway, Sweden, Denmark, Switzerland, and The Netherlands.Icelandic ...
Althoff, Kai: (from the article "Art and Art Exhibitions") ...(1930-98) in the U.S. since 1984 and included 375 works made over five decades. In his first American museum exhibition, held at the Institute of Contemporary Art, Boston, young German artist Kai Althoff presented 15 years' worth of work, including drawings, video, watercolours, installations, and music and texts, treating adolescence, ...
Althusius, Johannes: German political theorist who was the intellectual father of modern federalism and an advocate of popular sovereignty. [1 Related Articles]
Althusser, Louis: French philosopher who attained international renown in the 1960s for his attempt to fuse Marxism and structuralism. [1 Related Articles]
Altichiero: early Renaissance painter who was the effective founder of the Veronese school and perhaps the most significant northern Italian artist of the 14th century.
Altieri Chapel: (from the article "Bernini, Gian Lorenzo") Bernini's greatest late work is the simple Altieri Chapel in San Francesco a Ripa (c. 1674) in Rome. The relatively deep space above the altar reveals a statue representing the death of the Blessed Ludovica Albertoni. Bernini consciously separated architecture, sculpture, and painting for different roles, reversing the process that ...
altimeter: instrument that measures the altitude of the land surface or any object such as an airplane. The two main types are the pressure altimeter, or aneroid barometer, which approximates altitude above sea level by measuring atmospheric pressure, and the radio altimeter, which measures absolute altitude (distance above land or water) ... [2 Related Articles]
Altingia: (from the article "Saxifragales") Altingiaceae, or the sweet gum family, consists of one or two genera, Altingia and Liquidambar (sometimes included in Altingia). If Liquidambar is recognized as separate, it includes four species, one native to eastern North America and eastern Mexico and Central America, one from the eastern Mediterranean, and two from East ...
Altingia excelsa: (from the article "Hamamelidaceae") The timber of the Himalayan and tropical Asian genus Exbucklandia (by some authorities Symingtonia), which has two species, is much valued. Altingia excelsa, from Java, is one of the largest trees of the Asian tropics, sometimes reaching a height of 25 metres (82 feet) and having a bole diameter of ...
Altiplano: region of southeastern Peru and western Bolivia. The Altiplano originates northwest of Lake Titicaca in southern Peru and extends about 600 miles (965 km) southeast to the southwestern corner of Bolivia. It is a series of intermontane basins lying at about 12,000 feet (3,650 metres) above sea level. Lake Titicaca ... [10 Related Articles]
Altis: in Greek religion, the sacred grove of Zeus, or the sacred precinct in Olympia, Greece. It was an irregular quadrangular area more than 200 yards (183 m) on each side, and walled except to the north, where it was bounded by the Kronion (hill of Cronus). In it were the ... [1 Related Articles]
altitude: (from the article "climate") There are two main levels where the atmosphere is heated-namely, at Earth's surface and at the top of the ozone layer (about 50 km, or 30 miles, up) in the stratosphere. Radiation balance shows a net gain at these levels in most cases. Prevailing temperatures tend to decrease with distance ...
altitude above sea level: (from the article "barometer") ...is coupled mechanically to an indicating needle. A mercury barometer is used to calibrate and check aneroid barometers. Calibration can be, for example, in terms of atmospheric pressure or altitude above sea level. The concept of altitude above sea level, based on barometric pressure, is used to create one type ...
altitude and azimuth: in astronomy, gunnery, navigation, and other fields, two coordinates describing the position of an object above the Earth. Altitude in this sense is expressed as angular elevation (up to 90°) above the horizon. Azimuth is the number of degrees clockwise from due north (usually) to the object's vertical circle (i.e., ... [2 Related Articles]
altitude sickness: acute reaction to a change from sea level or other low-altitude environments to altitudes above 8,000 feet (2,400 metres). Altitude sickness was recognized as early as the 16th century. In 1878 French physiologist Paul Bert demonstrated that the symptoms of altitude sickness are the result of a deficiency of oxygen ... [3 Related Articles]
altitude-azimuth mounting: (from the article "telescope") ...While most reflectors have equatorial mounts similar to refractors, the world's largest reflector, the six-metre instrument at the Special Astrophysical Observatory in Zelenchukskaya, Russia, has an altitude-azimuth mounting. The significance of the latter design is that the telescope must be moved in both altitude and azimuth as it tracks a ...
Altizer, Thomas J.J.: radical theologian associated with the Death of God movement (q.v.) in the 1960s and '70s.
Altman, Benjamin: American merchant, art collector, and philanthropist who established one of the world's great department stores, B. Altman & Co.
Altman, Robert: unconventional and independent American motion-picture director, whose works emphasize character and atmosphere over plot in exploring themes of innocence, corruption, and survival. Perhaps his best-known film was his first and biggest commercial success, the antiwar comedy M*A*S*H (1970), set in a Mobile Army Surgical Hospital during the ... [4 Related Articles]
Altman, Sidney: Canadian-American molecular biologist who, with Thomas R. Cech, received the 1989 Nobel Prize for Chemistry for their discoveries concerning RNA, or ribonucleic acid. [2 Related Articles]