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Retrovirus associated with AIDS. HIV attacks and gradually destroys the immune system, leaving the host unprotected against infection. It cannot be spread through casual contact but instead is contracted mainly through exposure to blood and blood products (e.g., by sharing hypodermic needles or by accidental needle sticks), semen and female genital secretions, or breast milk. A pregnant woman can pass the virus to her fetus across the placenta. The virus first multiplies in lymph nodes near the site of infection. Once it spreads through the body, usually about 10 years later, symptoms appear, marking the onset of AIDS. Multidrug cocktails can delay onset, but missing doses can lead to drug resistance. Like other viruses, HIV needs a host cell to multiply. It attacks helper T cells and can infect other cells. A rapid mutation rate helps it foil both the immune system and treatment attempts. No vaccine or cure exists. Abstinence from sex, use of condoms or other means to prevent sexual transmission of the disease, and avoidance of needle sharing have reduced infection rates in some areas.
Activities that direct the flow of goods and services from producers to consumers. In advanced industrial economies, marketing considerations play a major role in determining corporate policy. Once primarily concerned with increasing sales through advertising and other promotional techniques, corporate marketing departments now focus on credit policies (see credit), product development, customer support, distribution, and corporate communications. Marketers may look for outlets through which to sell the company's products, including retail stores, direct-mail marketing, and wholesaling. They may make psychological and demographic studies of a potential market, experiment with various marketing strategies, and conduct informal interviews with target audiences. Marketing is used both to increase sales of an existing product and to introduce new products. See also merchandising.
Southernmost country on the African continent. The Kingdom of Lesotho lies within its boundaries. Area: 471,359 sq mi (1,220,813 sq km). Population (2009 est.): 49,321,000. Capitals: Pretoria/Tshwane (executive), Cape Town (legislative), Bloemfontein/Mangaung (judicial). Three-fourths of the population are black Africans, including the Zulu, Xhosa, Sotho, and Tswana; nearly all of the remainder are of European or mixed or South Asian descent. Languages: Afrikaans, English, Ndebele, Pedi (North Sotho), Sotho (South Sotho), Swati (Swazi), Tsonga, Tswana, Venda, Xhosa, Zulu (all official). Religions: Christianity (other [mostly independent] Christians, Protestant, Roman Catholic); also traditional beliefs, Hinduism, Islam. Currency: rand. South Africa has three major zones: the broad interior plateau, the surrounding mountainous Great Escarpment, and a narrow belt of coastal plain. It has a temperate subtropical climate. It is one of the world's major producers and exporters of gold, coal, diamonds, platinum, and vanadium. It is a multiparty republic with two legislative houses; its head of state and government is the president. San and Khoekhoe (Khoisan speakers) roamed the area as hunters and gatherers in the Stone Age, and the latter had developed a pastoralist culture by the time of European contact. By the 14th century, peoples speaking Bantu languages had settled in the area and developed gold and copper mining and an active East African trade. In 1652 the Dutch established a colony at the Cape of Good Hope; the Dutch settlers became known as Boers (Dutch: Farmers) and later as Afrikaners (for their Afrikaans language). In 1795 British forces captured the cape. In 1836 Dutch settlers seeking new land made the Great Trek northward and established (1838) the independent Boer republics of Orange Free State and the South African Republic (later the Transvaal region), which the British annexed as colonies by 1902 following the South African War. In 1910 the British colonies of Cape Colony, Transvaal, Natal, and Orange River were unified into the new Union of South Africa, which became independent and withdrew from the Commonwealth in 1961. Throughout the 20th century, South African politics were dominated by the question of maintaining white European supremacy over the country's black majority, and in 1948 South Africa formally instituted apartheid. Faced by increasing worldwide condemnation, it began dismantling the apartheid laws in 1990. In free elections in 1994, Nelson Mandela became the country's first black president. A permanent nonracial constitution was promulgated in 1997.
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