vertebral Vvar-'te-brel, 'vort-s-broR column or spinal column or spine or backbone Flexible column extending the length of the torso. In humans, it consists of 32-34 vertebrae, with different shapes and func¬ tions in each of five regions: 7 cervical, in the neck (including the atlas and axis, modified for free movement of the skull); 12 thoracic, in the chest; 5 lumbar, in the lower back; 5 sacral (fused into the sacrum, part of the pelvic girdle); and 3 to 5 coccygeal (vestigial tailbones fused into the coccyx). The body of each vertebra is separated from its neighbours by cushioning intervertebral disks of cartilage. Behind the body is a Y-shaped vertebral (neural) arch with structures extending up and down to form joints with the adjacent vertebrae and to the back and sides to provide attachment points for muscles and ligaments. The spine supports the torso and protects the spinal cord.
vertebrate Any animal of the chordate subphylum Vertebrata, which includes the fishes, amphibians, reptiles, birds, and mammals. Vertebrates have an internal skeleton formed of cartilage, bone, or both. The skeleton con¬ sists of a backbone (vertebral column), which partly encloses a spinal cord; a skull, which encloses the brain; and usually two pairs of limbs. Nerves extending from the spinal cord and brain permeate the skin, muscles, and internal organs. The muscular system consists primarily of bilaterally paired masses attached to bones or cartilage. Skin and scales, feathers, fur, or hair cover the outer surface. See also invertebrate.
vertical integration Form of business organization in which all stages of production of a good, from the acquisition of raw materials to the retailing of the final product, are controlled by one company. A current example is the oil industry, in which a single firm commonly owns the oil wells, refines the oil, and sells gasoline at roadside stations. In hori¬ zontal integration, by contrast, a company attempts to control a single stage of production or a single industry completely, which lets it take advantage of economies of scale but results in reduced competition.
vertigo \'v9r-t9-,go\ Feeling that one is spinning or that one’s surround¬ ings are spinning around one, causing confusion and difficulty keeping one’s balance, sometimes accompanied by nausea and vomiting. Vertigo is normal after actual spinning, since inner-ear fluid continues to move once the body has stopped, producing a mismatch between visual and internal sensations. Lack of a stable visual reference point also contrib¬ utes to this effect. Other causes include concussion and abnormalities of the inner ear (e.g., labyrinthitis; see otitis), of the nerves that carry sig¬ nals from it, or of the brain centers that receive them (e.g., stroke). Ver¬ tigo is often confused with a feeling of faintness (see syncope), since both are called dizziness. See also motion sickness, proprioception, spatial disori¬ entation.
vervain See verbena
vervet monkey or vervet Any of several African races of slim, arboreal, diurnal Old World monkeys of the guenon species Cercopithe- cus aethiops and C. pygerythrus (family Cercopithecidae). They have large cheek pouches. The arms and legs are long, and the nonprehensile tail is longer than the head-and-body length of 12-26 in. (30-65 cm). The soft, dense fur of many species has a speckled effect and bold markings of white or bright colours. The face, chin, hands, and feet of C. aethiops races are black.
Verwoerd ffsr-'viirtX, Hendrik (Frensch) (b. Sept. 8, 1901, Amster¬ dam, Neth.—d. Sept. 6, 1966, Cape Town, S.Af.) Dutch-bom South Afri¬ can prime minister (1958-66). He was taken to South Africa as an infant by his missionary parents. After studying at the University of Stellen¬ bosch, he became a professor there, and in 1937 he became editor of the Afrikaner nationalist daily in Johannesburg. Appointed senator (1948) and then minister of native affairs (1950), he was responsible for much of the country’s new apartheid legislation. When he became prime minister in 1958, his apartheid program was strictly enforced, and he pushed through legislation resettling blacks in reservations. His policies provoked dem¬ onstrations, sometimes violent. In 1960 white voters approved his rec¬ ommendation that South Africa leave the British Commonwealth, and his dream of a republic came true. He was stabbed to death in the parlia¬ mentary chamber by a parliamentary messenger of mixed descent.
Very Large Array (VLA) Radio telescope system consisting of 27 parabolic dishes. The most powerful radio telescope in the world, it has been operated on the plains of San Agustin near Socorro, N.M., U.S., by the National Radio Astronomy Observatory since 1980. Each dish is 82 ft (25 m) in diameter and can be moved independently by transporter along rails laid out in an enormous Y pattern whose arms are about 13 mi (21 km) long. The radio signals received by the dishes are integrated by computer, so the entire array acts as a single radio antenna (an inter¬ ferometer). The VLA, which has a maximum angular resolution better than a tenth of an arc second, has been responsible for producing many of the most detailed radio images of quasars; galaxies; supernovas; and the Milky Way Galaxy’s nucleus.
Vesalius Wo-'sa-le-osV Andreas Flemish Andries van Wesel (b.
Dec. 1514, Brussels—d. June 1564, island of Zacynthus, Republic of Venice) Flemish physician. Bom into a family of physicians, he studied medicine at the University of Paris. As a lecturer in surgery, he insisted on dissecting corpses himself, instead of relying on untrained assistants, to learn anatomy. Comparing his observations with ancient texts led him to question the theories of Galen, at that time still considered authorita¬ tive. Vesalius’s own complete textbook of human anatomy, the momen¬ tous De humani corporis fabrica libri septem (1543; “Seven Books on the Structure of the Human Body”), commonly called the Fabrica , was the most extensive and accurate description of the human body that had ever been published.
Vesey \'ve-ze\, Denmark (b. c. 1767, probably St. Thomas, Danish West Indies—d. July 2, 1822, Charleston, S.C., U.S.) U.S. insurrection¬ ist. Born into slavery, he was sold to a Bermuda slaver captain, with whom he sailed on numerous voyages. They settled in Charleston, S.C., and Vesey was allowed to purchase his freedom for $600 in 1800. After read¬ ing antislavery literature, he determined to oppose the oppression of slaves. He organized city and plantation blacks (up to 9,000 by some esti¬ mates) for an uprising in which they would attack arsenals, seize arms, kill all whites, bum Charleston, and free the slaves on surrounding plan¬ tations. After a house servant warned the authorities, the insurrection was forestalled and 130 blacks were arrested; Vesey was tried and hanged with 35 others.
Vespasian \ves-'pa-zh3n\ in full Caesar Vespasianus Augus¬ tus orig. Titus Flavius Vespa¬ sianus (b. Nov. 17?, ad 9, Reate,
Latium—d. June 24, 79) Roman emperor (69-79), founder of the Fla¬ vian dynasty. Although of humble birth, he won military glory in Brit¬ ain and was awarded a triumph by Claudius. In 63 he became proconsul of Africa. He reconquered Judaea except for Jerusalem (67-68) but stopped fighting on the death of Nero (68). After the murder of Galba, Ves¬ pasian was proclaimed emperor by the legions, while Vitellius claimed the title in Cologne; Vespasian’s forces soon defeated Vitellius in Italy. Although he claimed absolute power and took every possible office for himself and his sons, he was a