Adour \3-'dur\ River River, southwestern France. Flowing northwest from the Pyrenees, it traverses the scenic Campan valley; beyond Tarbes it feeds irrigation canals, most importantly the Canal d’Alaric. After a course of 208 mi (335 km), it empties into the Bay of Biscay below Bay¬ onne.
adrenal \9-'dre-n 3 l\ gland or suprarenal \ 1 su-pr9-'re-n 3 l\ gland Either of two small, triangular endocrine glands over the kidneys. In humans, each gland weighs about 0.15 oz (4.5 g) and consists of an inner medulla, which produces the catecholamine hormones epinephrine and norepinephrine, and an outer cortex (about 90% of the gland), which secretes the steroid hormones aldosterone, cortisol, and androgens (the last two in response to ACTH from the pituitary gland). Diseases of the adre¬ nal glands include pheochromocytoma (a tumour of the medulla) and the cortical disorders Addison disease, adrenal hypertrophy, Cushing syndrome, and primary aldosteronism.
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adrenaline ► advertising I 19
adrenaline See epinephrine
Adrian \'a-dre-3n\ IV orig. Nicholas Breakspear (b. 1100?, Abbot’s Langley, near St. Albans, Hertfordshire, Eng.—d. Sept. 1, 1159, Anagni, near Rome [Italy]) Pope (1154-59), the only Englishman ever to hold the office. He served in France and Italy before a successful mission to Scandinavia led to his election as pope. Adrian crowned Frederick I Bar- barossa emperor in 1155, after Frederick had turned over Arnold of Bres¬ cia, leader of a revolt in Rome. The relationship quickly soured, however, as a result of Adrian’s policy toward the Normans of southern Italy and his assertion that Frederick had received the imperial crown as a benefice. His controversial bull Laudabiliter supposedly gave Ireland to Henry II of England, a claim that was later refuted. Adrian’s refusal to recognize the king of Sicily, William I, stirred revolt in the Campania.
Adrian, Edgar Douglas later 1st Baron Adrian of Cambridge
(b. Nov. 30, 1889, London, Eng.—d. Aug. 4, 1977, London) British elec¬ trophysiologist. He amplified electrical potential variations in nerve impulses from sense organs to record ever smaller changes, eventually recording impulses from single sensory endings and motor nerve fibres. His work clarified the physical basis of sensation and the mechanism of muscular control. Adrian’s later studies of brain electrical activity included investigations into epilepsy and the location of cerebral lesions. He shared a 1932 Nobel Prize with Charles Sherrington.
Adrianople, Battle of or Battle of Hadrianopolis (ad 378) Battle fought in what is now Edirne, Tur., that marked the beginning of serious Germanic incursions into Roman territory. It pitted the Roman army under the emperor Valens against the horsemen of the Visigoths, Ostrogoths, and other Germanic tribes. The Roman army was annihilated and Valens died on the battlefield. His successor, Theodosius I, and the Goths agreed in 382 that the Goths would help with imperial defenses in exchange for food subsidies. The treaty set the pattern for later barbarian intrusions.
Adrianople, Treaty of see Treaty of Edirne
Adriatic Sea Arm of the Mediterranean Sea, lying between Italy and the Balkan Peninsula. It is about 500 mi (800 km) long, with an average width of 110 mi (175 km), a maximum depth of 4,035 ft (1,324 m), and an area of 50,590 sq mi (131,050 sq km). The Italian coast is relatively straight and continuous, having no islands, but the Balkan coast is full of islands, generally running parallel to the shore. The Strait of Otranto at its southeasterly limit links it with the Ionian Sea.
adsorption Capability of a solid substance (adsorbent) to attract to its surface molecules of a gas or solution (adsorbate) with which it is in con¬ tact. Physical adsorption depends on van der Waals forces of attraction between molecules and resembles condensation of liquids. In chemical adsorption (often called chemisorption; see catalysis), the gas is held to the surface by chemical forces specific to the chemicals involved, and formation of the bond may require an activation energy.
'Adullam Vo-'dol-omN Ancient village, Israel, about 15 mi (24 km) south¬ west of Jerusalem. A cave in its vicinity was from early times a place of refuge; it is mentioned several times in the Bible (e.g., as the place where David hid from Saul).
adult education See continuing education
adultery Sexual relations between a married person and someone other than his or her spouse. Prohibitions against adultery are found in virtu¬ ally every society; Jewish, Christian, and Islamic traditions all condemn it, and in some Islamic countries it is still punishable by death. Attitudes toward adultery in different cultures have varied widely. Under the Code of Hammurabi (18th century bc) in Babylonia it was punishable by death by drowning, and in ancient Rome an offending woman could be killed, though men were not severely punished. In western Europe and North America, adultery by either spouse is a ground for divorce, though in the U.S. the shift to no-fault divorce significantly reduced the importance of adultery as an element in divorce proceedings. The spread of Western ideas of equality in marriage has resulted in pressure for equal marital rights for women in traditional African and Southeast Asian societies.
adulthood Period in the human life span in which full physical and intellectual maturity have been attained. Adulthood is commonly thought of as beginning at age 20 or 21. It includes middle age (commencing around age 40) and old age (from about age 60). Physically, it is char¬ acterized by the peaking (around age 30) and gradual decline of bodily
functioning; the postpeak phase includes diminished acuity of the senses, reduction in muscular and skeletal mass, buildup of cholesterol in the arteries, weakening of the heart muscle, and diminished production of hormones. Some slowing in the rate of central-nervous-system process¬ ing also begins with middle age, but it is generally compensated for by an increased capacity to retain practical information and apply accumu¬ lated cultural knowledge. In old age, most individuals experience a sig¬ nificant decline in physical capacity, and many eventually also suffer impaired mental function.
Advaita \3d-'vl-t3\ (Sanskrit: “Nondualism”) Most influential school of Vedanta. It originated with Gaudapada’s 7th-century commentary on the Mandukya Upanishad. Gaudapada builds on the Mahayana Buddhist phi¬ losophy of emptiness, asserting that there is no duality; the mind, awake or dreaming, moves through maya (illusion). The mind’s ignorance con¬ ceals the truth that there is no becoming and no individual soul or self (jiva), only a temporary delineation from the atman (all-soul). In the 8th century Sankara developed Advaita further, arguing that the world is unreal and that the Upanishads teach the nature of Brahman, the only real¬ ity. The extensive Advaita literature influences modem Hindu thought.
Advent In the Christian calendar, the first season of the church year, a period of preparation for the birth of Jesus. Advent begins on the Sunday nearest to November 30 and continues until Christmas. Viewed as a peni¬ tential season, it is also considered a time of preparation for the Second Coming of Christ. The origin of Advent is unknown, but it was observed as early as the 6th century. In many countries it is celebrated with popu¬ lar customs such as the lighting of Advent candles.
Adventist Member of any of a group of Protestant churches that arose in the U.S. in the 19th century and believe that the Second Coming of Christ is close at hand. Adventism was founded during a period marked by millennialism by William Miller (1782-1849), a former U.S. army officer, who asserted that Christ would return to separate saints from sin¬ ners and inaugurate his 1,000-year kingdom on earth sometime in the year before March 21, 1844. After that date passed, Miller and his followers set a new date, Oct. 22, 1844. The “Great Disappointment” was followed by a Mutual Conference of Adventists in 1845. Those who persisted con¬ cluded that Miller had misinterpreted the signs and that, though Christ had begun the “cleansing of the heavenly sanctuary,” he would not appear until he had completed that task. These Millerites founded the Seventh- Day Adventists in 1863; other Adventist groups include the Evangelical Adventists and the Advent Christian Church. Seventh-Day Adventists observe Saturday as the Sabbath and avoid eating meat and using narcot¬ ics or stimulants.