ductus arteriosus Vdok-tos-ar-.tir-e-'o-sosN Channel between the pul¬ monary artery and the aorta in the fetus, which bypasses the lungs to dis¬ tribute oxygen received through the placenta from the mother’s blood. It normally closes once the baby is born and the lungs inflate, separating the pulmonary and systemic circulations. Closure before birth causes circu¬ latory problems. If the ductus stays open after birth (patent ductus arte¬ riosus, more common in premature births), oxygenated and deoxygenated blood mix. Alone, this may not be serious; in some heart malformations it is even necessary for life.
Dudley City (pop., 1998 est.: 311,500), West Midlands, England. It is the site of several Saxon and Norman fortifications. Coal and ironstone have been mined there since the Middle Ages. By the mid-19th century there were numerous blast furnaces, and the resultant pollution helped to give the area to the north and east the name “Black Country.” Metalwork¬ ing is an important industry.
Dudley, Dud (b. 1599, England?—d. 1684, England?) English iron¬ master. He was an illegitimate son of Edward Sutton, the 9th Baron of Dudley, who recalled him from Oxford in 1619 to manage the family’s ironworks in Staffordshire. He was the first to experiment with smelting iron ore in a coAL-fired furnace. Previously, charcoal had been exclusively used for smelting iron, but it was becoming increasingly costly, and unpopular, with the depletion of England’s forests for fuel. Dudley pat¬ ented his innovation in 1621, but the poor quality of his metal limited its sale. Dudley’s work culminated in Abraham Darby’s coKE-fired furnace in
Dudley, Robert See Earl of Leicester
due process Legal proceedings carried out fairly and in accord with established rules and principles. Due process standards are sometimes referred to as either substantive or procedural. Substantive due process refers to a requirement that laws and regulations be related to a legitimate government interest (e.g., crime prevention) and not contain provisions that result in the unfair or arbitrary treatment of an individual. The 5th Amendment to the Constitution of the United States states that “no person shall...be deprived of life, liberty, or property, without due process of law.” This right was extended to the states by the 14th Amendment (1868). Fundamental to procedural due process are adequate notice before the government can deprive one of life, liberty, or property, and the oppor¬ tunity to be heard and defend one’s rights. The boundaries of due process are not fixed and are the subject of endless judicial interpretation and decision making. See also rights of the accused; double jeopardy.
duel Formal combat with weapons fought between two persons in the presence of witnesses. Intended to settle a quarrel or point of honour, it
represented an alternative to the usual process of justice. The judicial duel, or trial by battle, is reported in ancient sources and was prevalent in medieval Europe. A judge could order two parties to meet in a duel to settle a matter. It was believed that through such an appeal to the “judg¬ ment of God” the righteous would emerge victorious; the loser, if still alive, was dealt with according to the law. Duels of honour were private encounters over real or imagined slights or insults. Eventually fought with pistols, duels were frequent in France and Germany in the 19th and early 20th centuries, and they were legal or encouraged by the fascist regimes in Italy and Germany. By the late 20th century they were prohibited; the last duel recorded in France occurred in 1967. The most famous duel in the U.S. was that between Alexander Hamilton and Aaron Burr (1804). See also ORDEAL.
Duero River See Douro River
Dufay \dLE-'fe\, Guillaume or Du Fay (b. c. 1400—d. Nov. 27,1474, Cambrai, Bishopric of Cambrai) Franco-Flemish composer, principal composer of the Burgundian school. As a boy he sang in the choir of Cambrai Cathedral. Ordained a priest, he acquired a high reputation for learnedness. In 1428 he joined the papal singers in Rome, by which time his works had made him famous. He returned to Cambrai c. 1440, where he would supervise the cathedral’s music for the rest of his life, apart from a period (1451-58) working for the duke of Savoy. Many musicians came to learn under him, and he enjoyed renown as the greatest living com¬ poser. His surviving works, which employ a richly harmonic texture, include some 90 chansons, 13 motets, and at least 6 complete masses, including such early cantus-firmus works as L’Homme arme and Se la face ay pale.
Dufy \dtE-'fe\, Raoul (b. June 3, 1877, Le Havre, Fr.—d. March 23, 1953, Forcalquier) French painter and designer. In 1900 he studied at the Ecole des Beaux-Arts in Paris and experimented with Impressionism, but by 1904 he had adopted the flat areas of bright colour typical of Fauvism. In the early 1920s he developed a distinctive style characterized by rapid calligraphic drawing on backgrounds of bright, decorative colour; his subjects were usually recreational scenes such as horse races, parades, and concerts. He also designed textiles and made numerous book illustrations.
dugong Vdii-.gaqV Large marine mammal ( Dugong dugon, the sole liv¬ ing member of the family Dugongidae) that lives in shallow coastal waters from the Red Sea and eastern Africa to the Philippines, New Guinea, and northern Australia. It is 7-11 ft (2.2-3.4 m) long and usually weighs 500- 800 lbs (230-360 kg). Its round, tapered body ends in a flipper with paired, pointed, horizontal branches. The forelimbs are rounded flippers; there are no hind limbs. The head blends into the body, and the snout is broad, square, and bristled. Dugongs live in pairs or in groups of up to six indi¬ viduals. Once heavily hunted for their meat, hides, and oil, they are now protected throughout most of their range, though some populations remain in danger of extermination. See also manatee, sea cow.
duiker Vdl-korV Any of 19 species of small, shy antelope. They live in most of Africa but are rarely seen by humans. The gray, or bush, duiker (Sylvicapra grimmia) has long legs and lives where there is bush or grass cover. It stands 22-26 in. (57-67 cm) tall at the shoulder. Only males have horns, which are short and straight.
Forest duikers (18 species, genus Cephalophus ) are short-legged, hunchbacked animals that live in dense brush and in forests. They stand 14-18 in. (36-46 cm) tall and vary from pale brown through red¬ dish brown to nearly black. Both sexes have short, straight horns.
Duisburg Vdii-es-.burkA English \'duz-barg\ City (pop., 2002 est.: 478,600), North Rhine-Westphalia state, western Germany. It lies at the junction of the Rhine and Ruhr rivers and is connected with the North Sea ports by the Rhine-Herne Canal. Known to the Romans as Castrum Deu- tonis, it was mentioned in ad 740 as Diuspargum, a seat of the Frankish kings. It passed to Cleves in 1290 and, with Cleves, to Brandenburg in 1614. After suffering heavily in the Thirty Years' War, it revived as the seat of a Protestant university from 1655 to 1818. With increasing indus¬ trialization after 1880, it is now one of the world’s largest inland ports.
Zebra duiker (Cephalophus zebra).
KENNETH W. FINK FROM THE NATIONAL AUDUBON SOCIETY COLLECTION/PHOTO RESEARCHERS-EB INC.
© 2006 Encyclopaedia Britannica, Inc.
578 I Dujardin ► Dumas
Dujardin XdiB-zhar-'daA, Felix (b. April 5, 1801, Tours, France—d. April 8, 1860, Rennes) French biologist. His studies of microscopic ani¬ mal life frequently found in decaying organic materials led him in 1834 to propose a new group of one-celled animals that he called Rhizopoda. He named the seemingly formless life substance that oozed outward through openings in certain shells sarcode', later it became known as pro¬ toplasm. This work led him in 1835 to argue against Christian Gottfried Ehrenberg’s theory that microscopic organisms have the same organs as higher animals. Dujardin also studied jellyfish, corals, and sea stars; his study of flatworms laid the foundation for the later development of the study of parasites and parasitism.