Alcmaeonid family \alk-'me-9n-id\ Athenian family important in the 6th-5th century bc. During the archonship (magistracy) of the Alcmae¬ onid Megacles (632? bc), the family was banished for murder; it returned twice to oust the tyrant Peisistratus before again being exiled. Megacles’ son Cleisthenes became archon in 525/524, but in 514 Peisistratus’ son Hippias again exiled the family for murdering his brother. The family reestablished itself after the Spartans drove out the Peisistratids in 510. The next generation may have aided the Persians at the Battle of Mara¬ thon (490). Alcibiades and Pericles were both Alcmaeonids.
Alcoa U.S. company, the world’s largest producer of aluminum. Estab¬ lished in Pittsburgh, Pa., in 1888, it adopted the name Aluminum Co. of America in 1907. Alcoa introduced aluminum foil in 1910 and found uses for aluminum in the emerging aviation and automobile industries. In 1913 it established the town of Alcoa in eastern Tennessee as a planned indus¬ trial community. A 1945 federal antitrust ruling obliged it to sell its Cana¬ dian subsidiary (now Alcan Aluminum Ltd., its strongest competitor). In 1998 Alcoa acquired Alumax Inc. Alcoa’s other products include plastic containers and packaging equipment.
alcohol Any of a class of common organic compounds that contain one or more hydroxyl groups (—OH) attached to one or more of the carbon atoms in a hydrocarbon chain. The number of other substituent groups (R) on that carbon atom make the alcohol a primary (RCH 2 OH), second-
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alcoholic beverage ► Aldrich I 41
ary (R 2 CHOH), or tertiary (R 3 COH) alcohol. Many alcohols occur natu¬ rally and are valuable intermediates in the synthesis of other compounds because of the characteristic chemical reactions of the hydroxyl group. Oxidation (see oxidation-reduction) of primary alcohols yields aldehydes and (if taken further) carboxylic acids; oxidation of secondary alcohols, ketones. Tertiary alcohols break down on oxidation. Alcohols generally react with carboxylic acids to produce esters. They may also be converted to ethers and olefins. Products of these numerous reactions include fats and waxes, detergents, plasticizers, emulsifiers, lubricants, emollients, and foaming agents. Ethanol (grain alcohol) and methanol (wood alcohol) are the best-known alcohols with one hydroxyl group. Glycols (e.g., ethylene glycol, or antifreeze) contain two hydroxyl groups, glycerol three, and polyols three or more. See also alcoholic beverage, alcoholism.
alcoholic beverage Any fermented liquor, such as wine, beer, or dis¬ tilled liquor, that contains ethyl alcohol, or ethanol, as an intoxicating agent. When an alcoholic beverage is ingested, the alcohol is rapidly absorbed in the stomach and intestines because it does not undergo any digestive processes. It is distributed to the rest of the body through the blood and has a pronounced depressant action on the brain. Under the influence of alcohol, the drinker is less alert, less able to discern objects in the environment, slower in reacting to stimuli, and generally prone to sleep.
Alcoholics Anonymous (AA) Voluntary fellowship of people suf¬ fering from alcoholism who seek to become and stay sober through mutual self-help by meeting in local, independent groups to share their common experience. Anonymity, confidentiality, and understanding of alcoholism as a disease free members to speak frankly. Many consider AA to be the most successful method of coping with alcoholism; participation raises the chances of success of other treatments. Its 12 steps to recovery include acknowledgment of the problem, faith in a “higher power” as understood by each individual, self-examination, and a desire to change for the bet¬ ter and to help others recover. Begun in 1935 by two alcoholics, AA has grown to some 2 million members worldwide. Similar organizations for abusers of other substances and for habitual gamblers and debtors are based on its principles.
alcoholism Excessive habitual consumption of alcoholic beverages despite physical, mental, social, or economic harm (e.g., cirrhosis, drunk driving and accidents, family strife, frequently missing work). Persons who drink large amounts of alcohol over time become tolerant to its effects. Alcoholism is usually considered an addiction and a disease. The causes are unclear, but there may be a genetic predisposition. It is more common in men, but women are more likely to hide it. Treatment may be physiological (with drugs that cause vomiting and a feeling of panic when alcohol is consumed; not an effective long-term treatment), psycho¬ logical (with therapy and rehabilitation), or social (with group therapies). Group therapies such as Alcoholics Anonymous are the most effective treatments. Suddenly stopping heavy drinking can lead to withdrawal symptoms, including delirium tremens.
Alcott, (Amos) Bronson (b. Nov. 29, 1799, Wolcott, Conn., U.S.—d. March 4, 1888, Concord, Mass.) U.S. teacher and philosopher. The self- educated son of a poor farmer, Alcott worked as a peddler before estab¬ lishing a series of innovative but ultimately unsuccessful schools for children. He traveled to Britain with money borrowed from Ralph Waldo Emerson and came back with the mystic Charles Lane, with whom he founded the short-lived utopian community Fruitlands outside Boston. Alcott is credited with establishing the first parent-teacher association in Concord, Mass., while he was superintendent of schools there. A promi¬ nent member of the Transcendentalists, he wrote a number of books but did not become financially secure until his daughter Louisa May Alcott achieved success.
Alcott, Louisa May (b. Nov. 29, 1832, Germantown, Pa., U.S.—d. March 6, 1888, Boston, Mass.) U.S. author. Daughter of the reformer Bronson Alcott, she grew up in Transcendentalist circles in Boston and Concord, Mass. She began writing to help support her mother and sisters. An ardent abolitionist, she volunteered as a nurse during the American Civil War, where she contracted the typhoid that damaged her health the rest of her life; her letters, published as Hospital Sketches (1863), first brought her fame. With the huge success of the autobiographical Little Women (1868-69), she finally escaped debt. An Old-Fashioned Girl (1870), Little Men (1871), and Jo’s Boys (1886) also drew on her expe¬ riences as an educator. See photograph above.
Alcuin \'al-,kwen\ (b. c. 732, in or near York, Yorkshire, Eng.—d. May 9, 804, Tours, France) Anglo-Latin poet, educator, and cleric. As head of Charlemagne’s Palatine school, he introduced the traditions of Anglo- Saxon humanism into western Europe and was the foremost scholar of the revival of learning known as the Carolingian Renaissance. He also made important reforms in the Roman Catholic liturgy, prepared an important new edition of the Vulgate Bible, wrote a number of poems, and left more than 300 Latin letters, a valuable source for the history of his time. Although traditionally identi¬ fied as the author of the Caroline books and as the creator of Carolin¬ gian miniscule, Alcuin is now recog¬ nized as having played a less important role in the creation of both. He was also an important political adviser and confidant of Charlemagne.
aldehyde Any of a class of organic compounds that contain a carbo¬ nyl group (—C=0; see functional group) in which the carbon atom is bonded to at least one hydrogen atom. Many have characteristic odours. Oxidation (see oxidation-reduction) of aldehydes yields acids; reduction produces alcohols. They participate in many chemical reactions and readily undergo polymerization into chains containing tens of thousands of the monomer molecule. The combination of aldehydes (e.g., formaldehyde) with other molecules results in several familiar plastics. Many aldehydes are large-scale industrial materials, useful as solvents, monomers, per¬ fume ingredients, and intermediates. Many sugars are aldehydes, as are several natural and synthetic hormones and compounds such as retinal (a derivative of vitamin A, important in vision) and pyridoxal phosphate (a form of vitamin B 6 ).