(1861-63).
Yang, Chen Ning known as Frank Yang (b. Sept. 22, 1922, Hofei, Anhwei, China) Chinese-born U.S. theoretical physicist. He immigrated to the U.S. in 1945 and studied with Edward Teller at the University of Chicago. He showed that parity is violated when elementary particles decay. This and other work in particle physics earned him and Tsung-Dao Lee (b. 1926) a 1957 Nobel Prize. His research focused mostly on inter¬ actions involving the weak force among elementary particles. He also worked in statistical mechanics.
Yang Hui literary name Qianguang (fl. c. 1261-75, Qiantang, Zhe¬ jiang province, China) Mathematician active in the great flowering of Chinese mathematics during the Southern Song dynasty. His books are among the few contemporary Chinese mathematics works to survive. A collected edition of his works (1378) was transmitted farther to the east, where it was particularly influential. In Korea it was reprinted during the reign of Sejong in 1433, and it was copied again by the Japanese math¬ ematician Seki Takakazu.
yang ban X'yaq-.banX Korean y/ 1wo groups" Highest social class of the Korean Choson dynasty (1392-1910). It consisted of both munban (civilian officials) and muban (military officials). Though the term origi¬ nated in the Koryo dynasty (935-1392), it was only later applied to the highest of four social classes. The yangban were granted land and sti¬ pends and were the only social class permitted to take the civil service examinations. The yangban system was discarded in 1894.
Yangdi or Yang-ti X'yaq-'deX orig. Yang Guang (b. 569, China—d. 618, Jiangdu, Jiangsu province) Second ruler of the Chinese Sui dynasty. Under Yangdi, canals were built and great palaces erected. In 608 he built a great canal linking the rice-producing areas in the south with the densely populated north, and he extended this system in 610, contributing to what
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Yangon ► Yarqon River i 2091
was to become the Grand Canal network. He embarked on military cam¬ paigns in Vietnam and Inner Asia. Three expeditions to Korea were so disastrous that the Chinese people turned against him; he was assassinated in southern China. One of his former officials reunited the empire and established the Tang dynasty. See also Wendi.
Yangon N.yaq-'gonV formerly Rangoon City (pop., 2004 est.: 4,455,500), principal port, and capital of Myanmar (Burma), on the Yangon River. It was a fishing village until the present city was founded in the mid-1750s by King Alaungpaya; he developed it as a port. The British occupied it 1824-26 during the First Anglo-Burmese War and again took it in 1852 during the Second Anglo-Burmese War. After the British annexation of all of Burma in 1886, Rangoon became the capital city. During World War II the Japanese advanced on and occupied the city, and it suffered considerable damage. It handles more than four-fifths of Myan¬ mar’s foreign commerce. In 2005 Myanmar government offices began to be moved to a new administrative centre at Pyinmana, some 200 mi (320 km) north of Yangon.
Yangshao culture Vyaq-'shaiA (5000-3000 bc) Prehistoric culture of China’s Huang He (Yellow River) basin, represented by several sites at which painted pottery has been uncovered. In Yangshao culture, millet was cultivated, some animals were domesticated, chipped and polished stone tools were used, silk was produced, and pottery was fired in kilns dug into the ground. See also Banpo.
Yangtze Gorges Dam Project See Three Gorges Dam Project
Yangtze Vyaq-'ts3\ River Chinese Chang \'chaq\ Jiang or Ch'ang Chiang River, China. Rising in the Tanggula Mountains in west-central China, it flows southeast before turning northeast and then generally east across south-central and east-central China to the East China Sea near Shanghai. It is known as the Jinsha in its upper course. It is the world’s third longest river, 3,915 mi (6,300 km) long. Its chief tributaries are the Yalong, Min, Jialing, Han, and Wu rivers. Several large cities, including Shanghai, Nanjing, Wuhan, and Chongqing, lie in the river’s basin, which is known as the granary of China. Large ships can sail to Wuhan, and smaller vessels can reach Yichang; it becomes harder to navigate above Yichang because of the gorges that occur between Chongqing and Yichang. Work on the con¬ troversial Three Gorges Dam Project —first discussed in the 1920s and pro¬ moted in the 1950s by Mao Zedong —was inaugurated in 1994. Located west of Yichang, it will enable freighters to navigate 1,400 mi (2,250 km) inland from the East China Sea to Chongqing.
Yanofsky \ya-'n6f-ske\, Charles (b. April 17, 1925, New York, N.Y., U.S.) U.S. geneticist. He received his Ph.D. from Yale University. He was part of the research team that first demonstrated that certain mutant genes produce inactive proteins. Later, working with E. coli, he showed that the sequence of the nitrogenous bases that form part of the structure of the genetic material corresponds to the amino acid sequence of proteins. Investigating the biochemical actions of suppressor mutations (changes in a gene that reverse the visible effects of mutation in a second gene), he found that suppression restored the ability to form an active enzyme in a mutant that had previously produced an inactive protein.
Yanomami or Yanomamo South American Indians who live in the remote forest of the Orinoco River basin in southern Venezuela and the northern reaches of the Amazon River basin in Brazil. They are hunters and gatherers who also grow crops in gardens by practicing shifting cul¬ tivation. Their reputation as a fierce people perpetually at war has been challenged since the late 20th century. Because their survival was threat¬ ened by incursions of Brazilian miners, in 1991 the Brazilian government set aside an area of 36,000 sq mi (93,000 sq km) as a homeland.
Yao Vyau\ Various Bantu-speaking peoples inhabiting southern Tanza¬ nia, northern Mozambique, and southern Malawi. In the colonial era the Yao were prominent as slave traders. They were never completely united but lived as small groups ruled by chiefs. By 1900 they had come under German, Portuguese, or British rule. Today numbering 2.2 million, the Yao practice shifting (slash-and-burn) horticulture. Most are Muslims.
Yao Yyau\ In Chinese mythology, one of three legendary emperors, along with Shun and Dayu, of the golden age of antiquity (c. 24th century bc). All three were exalted by Confucius as models of virtue, righteousness, and unselfish devotion. See photograph opposite.
Yaounde \yaun-'da\ City (pop., 2001 est.: urban agglom., 1,481,000), capital of Cameroon. It was founded in 1888 while Cameroon was a Ger¬
man protectorate. The area came under French control, and it was declared the capital of French Cameroun in 1922. In 1940-46 it was replaced as the capital by Douala, but, after Cameroon achieved independence in 1960, it again became the seat. It contains several small manufacturing and processing industries (sawmills and printing presses), and it is the area’s agricultural market.
Yaqui \'ya-ke\ American Indian people living in southern Sonora state on the west coast of Mexico. They were settled agriculturalists who offered stubborn resistance to the first Spanish invaders and only gradu¬ ally came under mission influence. In the 19th century they fought against Mexican encroachment on their fertile lands, and they were finally quelled with difficulty in 1887. Thousands were subsequently deported. In the 1930s much of their land was returned to them. Irrigation projects have led to a shift from subsistence agriculture to cash cropping (wheat, cot¬ ton, and crops for vegetable oil). They number about 25,000 in Mexico and more than 9,000 in Arizona.
Yarborough Yyar-.bur-oV Cale in full William Caleb Yarbor¬ ough (b. March 27, 1939, Timmonsvilie, S.C., U.S.) U.S. stock-car racer. He began racing stock cars in the early 1960s. He was the first to win the NASCAR championships for three consecutive years (1976-78). He also won the Daytona 500 three times (1968, 1977, 1983) and the Atlanta 500 four times (1967, 1968, 1974, 1981).