An Yu \'an-'yu\ or An Hyang \'an-'hyaq\ (b. 1243—d. 1306) Korean Neo-Confucian scholar and educator. In 1287 he accompanied King Chungnyol to the Mongol court in Beijing (Peking), where he encoun¬ tered the texts of Zhu Xi. Returning to Korea, An Yu used Neo-Confucian thought as the basis for promoting education. He helped reconstitute the National Academy and established a state treasury for national education. Eventually he became director of the Munmyo, the Korean national shrine to culture. Known as an opponent of Son (Zen) Buddhism in Korea, he was the most famous Confucian scholar of his era. See also Neo- Confucianism.
Anabaena \ l an-3- , be-no\ Genus of blue-green algae (cyanobacteria). Found as piankton in shallow water and on moist soil, they occur in both solitary and colonial forms and are capable of nitrogen fixation. In north¬ ern latitudes in summer, extensive growth of Anabaena may form water blooms that remain suspended instead of forming a surface scum. A toxic substance produced is fatal to cattle and other animals if present in drink¬ ing water in sufficient concentration.
Anabaptist Member of a movement of the Protestant Reformation char¬ acterized by adult baptism. Anabaptists held that infants were not punish¬ able for sin because they had no awareness of good and evil and thus could not yet exercise free will, repent, and accept baptism. Denying the valid¬ ity of infant baptism, they accepted adult baptism, which was regarded as a second baptism by those outside the group who identified them as Anabaptists (from the Greek for rebaptizers). Confident of living at the end of time, early Anabaptists sought to restore the institutions and spirit of the primitive church. The first adult baptisms took place outside Zurich in early 1525. Most Anabaptists were pacifists and refused to swear civil oaths. Thomas MOntzer advocated a more violent eschatology that called for the overthrow of the rich by the poor and was executed after leading the Thuringian peasant revolt (1525). Another group of Anabaptists, led by John of Leiden, took control of the city of Munster and sought to establish the millennial kingdom. Their excesses led to their violent sup¬ pression in 1535 and further persecution and martyrdom of the Anabap¬ tists. Many Anabaptists settled in Moravia, where they stressed the community of goods modeled on the primitive church at Jerusalem. This branch continues as the Hutterite movement, primarily in the western U.S. and Canada. Increasingly persecuted throughout Europe, Anabaptists in the Netherlands and northern Germany rallied under the leadership of Menno Simonsz. and survive as the Mennonites.
anabolic \,a-n9-'ba-lik\ steroid Steroid hormone that increases tissue growth. Anabolic steriods are given to elderly or postoperative patients to promote muscle growth and tissue regeneration. Unsupervised use by athletes to build muscle and improve strength can have serious harmful effects, including coronary heart disease, sexual and reproductive disor¬
ders, immunodeficiencies, liver damage, stunted growth, aggressive behaviour, susceptibility to connective-tissue injury, and (in females) irre¬ versible masculinization.
Anacletus \,an-3-'klet-9s\ II orig. Pietro Pierleoni (b. Rome—d. Jan. 25, 1138, Rome) Antipope (1130-38). Named a cardinal at Rome in 1116, he was elected pope by a majority of cardinals in 1130, while a minority created a schism by choosing Innocent II. Anacletus forced the rival pope to flee to France, where Innocent was supported by a church council and, especially, by Bernard of Clairvaux. Innocent’s supporters, including the Holy Roman and Byzantine emperors, invaded Italy in an unsuccessful effort to restore him. A second expedition in 1136 eroded support for Anacletus, who died before the issue was resolved by the sub¬ mission of his successor to Innocent.
anaconda Either of two South American snake species in the genus Eunectes (family Boidae) that con¬ strict their prey. The heavily built giant anaconda, or great water boa, is usually not more than 16 ft (5 m) long but can be longer than 24 ft (7.5 m), rivaling the largest pythons in length. The yellow anaconda is much smaller. Typically dark green with alternating oval black spots, the giant anaconda lives along tropical rivers east of the Andes and in Trinidad. It kills at night by lying in wait in water; it constricts prey as large as young pigs or caimans and occasionally forages in trees for birds. It may bear 75 live young at a time.
Anacreon or Anakreon \3-'nak-re-3n\ (b. c. 582 bc, Teos, Ionia—d. c. 485) Last great lyric poet of Asian Greece. Only fragments of his poetry have survived. Though he may have written serious poems, the poems quoted by later writers are chiefly in praise of love, wine, and revelry. His sentiments and style were widely imitated, and the anacreontic metre in poetry was named for him.
Anadolu See Anatolia
Anaheim City (pop., 2000: 328,014), southwestern California, U.S. Lying on the plain of the Santa Ana River 25 mi (40 km) southeast of Los Angeles, it was founded by German immigrants in 1857 as a cooperative agricultural community. After 1950 its citrus groves and vineyards had all but disappeared in the Los Angeles-Orange Co. urban-industrial expan¬ sion. Walt Disney’s first amusement park, Disneyland, opened there in 1955. Today it is a prominent convention site.
anal canal End portion of the alimentary canal, distinguished from the rectum by the transition from an internal mucous membrane layer to one of skinlike tissue and by its narrower diameter. Waste products move from the rectum to the anal canal. The human anal canal is 1-1.5 in. (2.5^4 cm) long and has three parts: upper, with longitudinal folds (rectal columns); lower, with involuntary and voluntary constrictive muscles (sphincters) to control discharge of feces; and the anal opening itself. Enlargements of the ends of rectal and anal veins are called hemorrhoids.
Analects See Lunyu
analgesic \,an-9l-'je-zik\ Drug that relieves pain without blocking nerve impulse conduction or markedly altering sensory function (see nervous system). Two classes are defined by the type of pain-relieving action. Opi¬ oids (opiates and synthetic narcotics; see opium) act on brain receptors to inhibit pain impulses. They may be used for short- or long-term pain relief, usually by prescription, but carry a risk of drug addiction. Non¬ opioids, used mostly for short-term relief and modest pain, are available without prescription. They include NSAIDs (including aspirin and ibupro- fen) and acetaminophen; all act by inhibiting synthesis of prostaglandins, molecules involved in the peripheral perception of pain.
analog computer Computer in which continuously variable physical quantities, such as electrical potential, fluid pressure, or mechanical motion, are used to represent (analogously) the quantities in the problem to be solved. The analog system is set up according to initial conditions and then allowed to change freely. Answers to the problem are obtained by measuring the variables in the analog model. Analog computers are especially well suited to simulating dynamic systems; such simulations
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66 I analysis ► Anasazi
may be conducted in real time or at greatly accelerated rates, allowing experimentation by performing many runs with different variables. They have been widely used in simulating the operation of aircraft, nuclear power plants, and industrial chemical processes. See also digital computer.
analysis In chemistry, the determination of the properties and compo¬ sition of samples of materials; qualitative analysis establishes what is there, and quantitative analysis measures how much. A large body of sys¬ tematic procedures (analytical chemistry) has evolved in close associa¬ tion with other branches of the physical sciences since their beginnings. A sample of a single compound may be analyzed to establish its elemen¬ tal composition (see element, molecular weight) or molecular structure; many measurements use spectroscopy and spectrophotometry. A mixed sample is usually analyzed by separating, detecting, and identifying its components by methods that depend on differences in their properties (e.g., volatility, mobility in an electric or gravitational field, distribution between liquids that do not mix). The many types of chromatography are increasingly useful, particularly with biological and biochemical samples.