terza rima Vtert-so-'re-moX Verse form consisting of tercets, or three- line stanzas, in which the second line of each rhymes with the first and third lines of the next. The series ends with a separate line that rhymes with the second line of the last stanza, so that the rhyme scheme is aba , bcb, cdc, ..., yzy, z . Dante, in The Divine Comedy (c. 1310-14), was the first to use terza rima in a long poem. A demanding form, it has not been widely adopted in languages less rich in rhymes than Italian. It was intro¬ duced into England by Thomas Wyat in the 16th century. Poets who have experimented with terza rima include Percy B. Shelley, Robert Browning, Elizabeth Barrett Browning, and W.H. Auden; Derek Walcott’s book-length Omeros is written in modified terza rima.
Teschen \'te-shon\ Former eastern European duchy. It was originally a principality linked to the Polish duchy of Silesia, and passed in 1526 to the Habsburgs. Though most of Silesia was seized by Prussia in 1742, Teschen remained under Habsburg rule until the end of World War I. In 1920 Poland and Czechoslovakia contested and then divided the region; Poland received the eastern district, including the city of Teschen (now Cieszyn), while Czechoslovakia received the rest. The Czechs were forced to cede their section to Poland in 1938. Germany occupied the entire region until after World War II, when the 1920 borders were restored.
Tesla, Nikola (b. July 9/10, 1856, Smiljan, Lika, Austria-Hungary—d. Jan. 7, 1943, New York, N.Y., U.S.)
Serbian U.S. inventor and researcher.
He studied in Austria and Bohemia and worked in Paris before coming to the U.S. in 1884. He worked for Thomas Alva Edison and George Westinghouse but preferred indepen¬ dent research. His inventions made possible the production and distribu¬ tion of alternating-current electric power. He invented an induction coil that is still widely used in radio tech¬ nology, the Tesla coil (c. 1890); his system was used by Westinghouse to light the 1893 World’s Columbian Exposition. Tesla established an electric power station at Niagara Falls in 1893. His research also included work on a carbon button lamp and on the power of electrical resonance. He discovered terrestrial stationary waves (1899-1900), prov¬ ing that the Earth is a conductor. Due to lack of funds, many of his ideas remained only in his notebooks, which are still examined by engineers for inventive clues.
Test Act (1673) Act passed by the British Parliament that required hold¬ ers of civil and military offices to profess the established religion and to receive Holy Communion according to the rites of the Church of England. Though directed primarily against Roman Catholics, it extended in prin¬ ciple to all non-Anglicans; it was modified in 1689 to enable most non- Catholics to qualify. An act adopted in 1828 removed the test. In the U.S. Constitution, Article VI prescribes that “no religious test” shall be required for any officeholder. See also Catholic Emancipation.
Nikola Tesla.
CULVER PICTURES
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testcross ► Teutonic Order I 1891
testcross Experiment in which an organism with unknown genetic makeup is mated with an organism whose entire genetic makeup for a trait is known, to determine which genes are carried by the former. In a breed of dog, for example, in which the gene for black coat colour is dominant over the gene for red coat colour (see dominance), a dog with a black coat may be pure (with two genes for black coat colour) or hybrid (with one gene for black and one for red). When its mating with a red- coated dog (which always has two genes for red coat colour only) pro¬ duces only black offspring, the black-coated parent must be pure, whereas if some of the young are red, the parent must be hybrid.
testes or testicles Male reproductive organs (see reproductive system). Humans have two oval-shaped testes 1.5-2 in. (4-5 cm) long that produce sperm and androgens (mainly testosterone), contained in a sac (scrotum) behind the penis. Each testis is divided into 200-400 lobes containing three to 10 very thin coiled tubes (seminiferous tubules) each, which produce the sperm and contract to expel them through a complex network of canals to another structure in the scrotum, the epididymis, for temporary storage. The cells in the testes are undeveloped in early childhood; at puberty they are stimulated by hormones to develop into fertile sperm cells.
testicular cancer Malignant tumour of the testis, or testicle. Although relatively rare, testicular cancer is the most common malignancy for men between the ages of 20 and 34. It typically affects men between 15 and 39 years old. A developmental abnormality of males in which one or both testes fail to descend into the scrotum about the time of birth increases the risk of developing the cancer later in life. The most notable symptom of testicular cancer is the formation of a painless lump in either testis. Treatment usually consists of the surgical removal of the cancerous tes¬ tis, followed by radiation therapy or chemotherapy if the cancer has metastasized.
testing machine Machine used in materials science to determine the properties of a material. Machines have been devised to measure tensile strength, strength in compression, shear, and bending (see strength of MATERIALS), DUCTILITY, HARDNESS, impact Strength (see IMPACT TEST), FRACTURE toughness, creep, and fatigue. Standardization of machines and tests is the province of the International Organization for Standardization, American National Standards Institute, British Standards Institution, and many gov¬ ernmental bodies. Many industries have special-purpose testing machines for the materials they use.
testosterone Ues-'ta-stor-.onX Masculinizing sex hormone produced by the testes. It is responsible for the development of the male sex organs and secondary sex characteristics (e.g., facial hair, masculine musculature, deep voice, and male-pattern baldness). Testosterone can be manufactured by modifying other, less expensive steroids. It is used in the treatment of hypogonadism, undescended testes (cryptorchism), and certain cancers.
tetanus Vte-t9-nss\ or lockjaw Acute bacterial disease caused by Clostridium tetani (see Clostridium). Spores of this organism are common, especially in soil; it thrives away from oxygen in deep wounds, especially punctures. Its toxin stimulates nerves, causing muscle rigidity with fre¬ quent spasms. This may occur around the site of the wound or, if the toxin reaches spinal motor ganglia via the bloodstream, throughout the body. The jaw muscles are almost always involved (lockjaw). Vaccination every few years is the best protection; an antitoxin prevents or delays symptoms in cases of suspect wounds but has limited value once they develop. Treatment usually includes antibiotics, sedatives, and muscle relaxants. Recovered patients are not immune.
Tetley (Jr.), Glen(ford Andrew) (b. Feb. 3, 1926, Cleveland, Ohio, U.S.) American dancer, choreographer, and ballet director. He trained in modern dance with Hanya Holm and Martha Graham. Between 1946 and 1962 he danced in Broadway musical productions as well as with dance companies such as the American Ballet Theatre. He became a choreogra¬ pher in 1962, forming his own company and creating Pierrot Lunaire. Subsequently he staged works with most of the major dance companies throughout the world. Tetley’s work helped to bring about a synthesis of modern dance and classical ballet. His creative staging and daring, often sexual, subject matter were sometimes controversial, but he was praised for the passion and strong physicality of his work.
Teton \'te-,tan\ Range Segment of the Middle Rocky Mountains, north¬ western Wyoming, U.S. The range extends 40 mi (64 km) across Wyo¬ ming, from the southern boundary of Yellowstone National Park to Teton Pass. Some foothills reach as far as southeastern Idaho. Many peaks