under the rays of the sun god Aton, altar relief, mid-14th century bc; in the State Museums at Berlin
FOTO MARBURG-ART RESOURCE
atonality \,a-to-'na-l3-te\ In music, the absence of functional harmony as a primary structural element. Probably originally a pejorative term applied to music of extreme chromaticism, it has become the most widely used descriptive term for 20th-century music whose connection with tonality is difficult to hear. Arnold Schoenberg and his students Alban Berg and Anton Webern are regarded as the seminal atonal composers; the serialism of their later work is often distinguished from their earlier “free atonality.”
atonement Religious concept in which obstacles to reconciliation with God are removed, usually through sacrifice. Most religions have rituals of purification and expiation by which the relation of the individual to the divine is strengthened. In Christianity, atonement is achieved through the death and resurrection of Jesus. In Roman Catholicism, Eastern Orthodoxy, and some Protestant churches, penance is a sacrament that allows for per-
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128 I Atonement ► attic
sonal atonement (see confession). In Judaism the annual Day of Atone¬ ment, Yom Kippur, is the culmination of 10 days centered on repentance.
Atonement, Day of See Yom Kippur
ATP in full adenosine triphosphate \9-'de-n3- 1 sen-tri- , fas- 1 fat\ Organic compound, substrate in many enzyme-catalyzed reactions (see catalysis) in the cells of animals, plants, and microorganisms. ATP’s chemical bonds (see bonding) store a large amount of chemical energy. ATP therefore functions as the carrier of chemical energy from energy- yielding oxidation (see oxidation-reduction) of food to energy-demanding cellular processes. Three such processes of metabolism are sources of ATP and stored energy: fermentation, the tricarboxylic acid cycle, and cellular respiration (also called oxidative phosphorylation). All form ATP from adenosine monophosphate (AMP) or adenosine diphosphate (ADP) and inorganic phosphate. When the reaction goes in the other direction, ATP is broken down to ADP or AMP and phosphate, and the released energy is used to perform chemical, electrical, or osmotic work for the cell.
atresia and stenosis \3- , tre-zh3...ste-'no-s3s\ Absence (atresia), usu¬ ally congenital, or narrowing (stenosis) of almost any normal body cav¬ ity or passage. The more important include atresia of the anus, esophagus, aortic arch, heart valves, and urinary passages; and stenosis of the intes¬ tine, urinary passages, pyloric valve (stomach outlet), and heart valves. Most must be surgically corrected soon after birth.
Atreus \'a-tre-os\ In Greek legend, the son of Pelops. Atreus became king of Mycenae and drove out his brother Thyestes. Plagued by a curse on the house of Pelops, Atreus murdered his own son Pleisthenes and was eventually killed by the nephew he had raised as a son. Two more sons, Agamemnon and Menelaus, fought in the Trojan War.
atrial Va-tre-oP fibrillation Irregular rhythm (arrhythmia) of contrac¬ tion of the atria (upper heart chambers). The most common major arrhyth¬ mia, it may result as a consequence of increased fibrous tissue in the aging heart, of heart disease, or in association with severe infection. If it con¬ tinues, it can permit formation of blood clots, which can block blood flow to essential organs. Emergency treatment consists of drugs such as beta- blockers or digitalis, which slow the heart’s action, and anticoagulants. In addition, atrial fibrillation can be interrupted by administering electric shocks (defibrillation). See also ventricuiar fibrillation.
atrium Va-tre-onP In an ancient Roman house, an open central court that contained the impluvium, a basin where rainwater collected. It originally contained the health and functioned as the center of family life. The term later came to be used for the open front courtyard of a Christian basilica, where congregants collected before services. The atrium was revived in the 20th century in the form of glass-covered, greenery- filled multistory spaces sometimes found in shopping centers, office buildings, and large hotels.
atrophy Va-tr9-fe\ Decrease from previous normal size of the body or a part, cell, organ, or tissue. An organ or body part’s cells may be reduced in number, size or both. Atrophy of some cells and organs is normal at certain points in the life cycle. Other causes include malnutrition, disease, disuse, injury, and hormone over- or underproduction.
atropine \'a-tra-,pen\ Anticholinergic drug. A poisonous, crystalline alkaloid derived from certain nightshade plants, especially Egyptian hen¬ bane, atropine is used chiefly to dry up bodily secretions, to dilate the bronchi, to prevent excessive cardiac slowing during anesthesia, and in ophthalmology to dilate the pupil of the eye. It works by suppressing the parasympathetic nervous system. Atropine is also used as an antidote for nerve gas poisoning.
Atsumi Kiyoshi (b. March 10, 1928, Tokyo, Japan—d. Aug. 4, 1996, Tokyo) Japanese comic actor. Atsumi grew up in an impoverished section of Tokyo and took odd jobs in the theatre before first portraying the role of Tora-san for a television film in 1968. He went on to play the char¬
acter until 1996 in the 48-film series Otoko wa tsurai yo (“It’s Tough Being a Man”), the longest-running series in which the same actor por¬ trayed the central character. Tora-san, a middle-aged peddler, is a charm¬ ingly irresponsible rogue who sells trinkets to passersby and unsuccessfully courts pretty women. Atsumi infused the role with witty wordplay and a folksy sincerity.
attainder In English law, the extinction of civil and political rights after a sentence of death or outlawry, usually after a conviction of treason. A legislative act attainting a person without trial was known as a bill of attainder. The most important consequences of attainder were forfeiture of property and “corruption of blood,” meaning that the attainted person was disqualified from inheriting or transmitting property, thus disinheriting his descendants. All forms of attainder except forfeiture following indictment for treason were abolished in the 19th century. As a result of the English experience, the U.S. Constitution provided that “no Attainder of Treason shall work Corruption of Blood, or Forfeiture except during the Life of the Person attainted.” The U.S. Supreme Court has also struck down as bills of attainder such things as the test oaths passed after the Civil War to dis¬ qualify Confederate sympathizers from certain professions.
Attalus I Soter \ , at-3-bs... , s6t-3r\ (b. 269—d. 197 bc) Ruler of Perga- mum (241-197). He crushed an attack by the Galatians (c. 230) and won most of Anatolia (228) through victory over the SELEUCID king, though by 222 the Seleucids had won most of it back. With Rome Attalus fought the First and Second Macedonian Wars, but he died shortly before Philip V’s defeat. He was celebrated as a patron of the arts.
Attenborough, Sir David (Frederick) (b. May 8, 1926, London, Eng.) British television writer. For the BBC, which he joined in 1952, he originated the series Zoo Quest (1954-64). As controller of BBC-2 (1965— 68) and director of programs (1968-72), he helped produce The Forsyte Saga, The Ascent of Man, and Civilisation. As an independent producer, he made innovative educational programs such as Life on Earth (1979) and The Living Planet (1984). He was knighted in 1985.
attention In psychology, the act or state of applying the mind to an object of sense or thought. Wilhelm Wundt was perhaps the first psycholo¬ gist to study attention, distinguishing between broad and restricted fields of awareness. He was followed by William James, who emphasized active selection of stimuli, and Ivan Pavlov, who noted the role attention plays in activating conditioned reflexes. John B. Watson sought to define atten¬ tion not as an “inner” process but rather as a behavioral response to spe¬ cific stimuli. Psychologists today consider attention against a background of “orienting reflexes” or “preattentive processes,” whose physical corre¬ lates include changes in the voltage potential of the cerebral cortex and in the electrical activity of the skin, increased cerebral blood flow, pupil dilation, and muscular tightening. See also attention deficit disorder.