Arta, Gulf of Inlet of the Ionian Sea, western Greece. It is 25 mi (40 km) long and 4-10 mi (6-16 km) wide. On its shores are the ruins of several cities important in ancient Greece. The seaport of Preveza, founded 290 bc, is to the north; the Battle of Actium took place near the gulf’s entrance.
Apollo. Accompanied by nymphs, she danced in mountains and forests. She both killed game and, as Mistress of Animals (see Master of the Animals), protected it. Stories of her nymphs’ love affairs may originally have been told of the goddess herself, but poets after Homer stressed her chastity. She was known for her unpitying wrath when offended. Artemis may have developed out of Ishtar in the East. Her Roman counterpart was Diana.
Artemisia \,art-9-'miz-e-3\ I (fl. 5th century bc) Queen of Halicarnas¬ sus and of the island of Cos c. 480 bc. She ruled under the Persian king Xerxes and helped him invade Greece (480^179). She commanded five ships in the Battle of Salamis; according to Herodotus, she advised Xerxes to retreat from Greece rather than risk another engagement.
Artemisia II (d. c. 350 bc) Sister and wife of King Mausolus (r. 377-353 bc) of Caria, southwestern Anatolia, and sole ruler for about three years after his death. She built his tomb, the Mausoleum, considered one of the Seven Wonders of the World.
arteriography See angiography
arteritis N.ar-ts-'rl-tosV Inflamma¬ tion of the arteries. It occurs in dis¬ eases including syphilis, tuberculosis, and lupus erythematosus. Varieties not closely associated with systemic dis¬ ease or disease of an organ outside the cardiovascular system have been described as temporal arteritis, poly¬ myalgia rheumatica, and polyarteri¬ tis nodosa.
artery Vessel that carries blood from the heart to other parts of the body (see cardiovascular system).
Arterial blood carries oxygen and nourishment to tissues; the one exception is the pulmonary artery, which conveys oxygen-depleted blood from the heart to the lungs for oxygenation and removal of excess carbon dioxide. Arteries are muscu¬ lar, elastic tubes that transport blood under the pressure of the heart’s pumping action, which can be felt as the pulse. Large arteries branch off from the aorta and give rise to smaller arteries, down to the threadlike arterioles, which branch into cap¬ illaries. An artery wall’s inner layer (tunica intima) consists of an endo¬ thelial (cellular) lining, a fine connective tissue network, and a layer of elastic fibres. The middle layer (tunica media) is mostly smooth muscle cells. The outer layer (tunica externa) contains supportive collagen fibres. See also capillary; vein.
"The Whiplash," Art Nouveau tapestry by Hermann Obrist, silk embroidered on wool, 1895; in the Munchner Stadt- museum, Munich.
COURTESY OF THE MUNCHNER STADTMUSEUM, MUNICH
Artemisia II, statue by an unknown art¬ ist; in the National Archeological Museum, Naples.
ANDERSON—AUNARI FROM ART RESOURCE
Artaud \ar-'to\, Antonin (b. Sept. 4, 1896, Marseille, France—d. March 4, 1948, Ivry-sur-Seine)
French poet, actor, and drama theo¬ rist. He wrote Surrealist poetry from 1925 and made his acting debut in Surrealist productions in Paris. He described his theory of drama in the Manifesto of the Theatre of Cruelty (1932; see Theatre of Cruelty) and The Theatre and Its Double (1938).
His own plays (including Les Cenci,
1935) were failures, but his theories exerted great influence on play¬ wrights of the Theatre of the Absurd.
Lifelong mental illness confined him periodically to asylums from 1936.
Artemis Var-to-mosV In Greek reli¬ gion, the goddess of wild animals, the hunt, vegetation, chastity, and child¬ birth. Artemis was the daughter of Artaud 1948.
Zeus and Leto and the twin sister of denise colomb-j.p. ziolo
artemisia V.ar-to-'mi-zhoV Any of a genus ( Artemisia ) of aromatic herbs and shrubs in the composite family. Examples include worm¬ wood, SAGEBRUSH, and TARRAGON.
Many species are valued as orna¬ mentals for their attractive silvery gray foliage, which is frequently used in horticultural plantings to cre¬ ate contrast or to smooth the transi¬ tion between intense colors. The leaves of common wormwood (A. absinthium ) have been used in medi¬ cines and beverages such as absinthe and vermouth. An extract from the Eurasian A. annua is used to treat quinine-resistant malaria.
Artemis as a huntress, classical sculp¬ ture; in the Louvre.
AUNARI/ART RESOURCE
© 2006 Encyclopaedia Britannica, Inc.
arthritis ► Arthur's Pass I 111
centipede class Chilopoda
subphylum Uniramia
subphylum Chelicerata
barnacle class Cirripeda
eye
telson
uropod
shrimp class Malacostraca
subphylum Crustacea
carapace
antennule
tail
(pygidium)
trilobite
subphylum Trilobita
eye
thorax
antenna
head
(cephalon)
Representative arthropods. Uniramia, the largest of the arthropod subphyla, contains mostly terrestrial insects and myriapods (including centipedes and millipedes). The insects, the largest arthropod class, differ from other arthropods in that they are usually winged and have only three pairs of legs. Members of the Crustacea subphylum are mostly marine-dwelling and include the shrimps, lobsters, crabs, and barnacles. The microscopic water fleas are chiefly found in fresh water and, along with other minute members of this subphylum, are part of the zooplankton. Most members of the Chelicerata subphylum are arachnids, including the spiders, scorpions, ticks, and mites. The trilobites (members of the Trilobita subphylum) are extinct marine arthropods that flourished during the Cambrian Period. Fossilized remains show a body having three lon¬ gitudinal lobes divided into three regions—head, thorax, and tail.
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arthritis \ar-'thri-t9s\ Inflammation of the joints and its effects. Acute arthritis is marked by pain, redness, and swelling. The principal forms are osteoarthritis, rheumatoid arthritis, and septic arthritis. Several forms of arthritis are part of the symptom complexes of autoimmune diseases.
arthropod Any member of the largest phylum, Arthropoda, in the ani¬ mal kingdom. Arthropoda consists of more than one million known inver¬ tebrate species in four subphyla: Uniramia (five classes, including insects), Chelicerata (three classes, including arachnids and horseshoe crabs), Crus¬ tacea (crustaceans), and Trilobita (trilobites). All arthropods are bilaterally symmetrical and possess a segmented body covered by an exoskeleton containing chitin, which serves as both armour and a surface for muscle attachment. Each body segment may bear a pair of jointed appendages. The phylum includes carnivores, herbivores, omnivores, detritus feeders, filter feeders, and parasites (see parasitism) in nearly all environments, both aquatic and terrestrial. See illustration above.
Arthur, Chester A(lan) (b. Oct. 5,1829, North Fairfield, Vt., U.S.—d. Nov. 18, 1886, New York, N.Y) 21st president of the U.S. (1881-85). He practiced law in New York City from 1854, later becoming a close asso¬ ciate of Sen. Roscoe Conkling, the Republican boss of New York. With Conkling’s backing, he was appointed customs collector for the port of New York (1871-78), an office long known for its use of the spoils sys¬ tem. He conducted the business of the office with integrity but continued to pad its payroll with Conkling loyalists. At the Republican national con¬ vention in 1880, Arthur was the compromise choice for vice president on
a ticket with James Garfield; he became president on Garfield’s assassina¬ tion. As president, Arthur displayed unexpected independence by vetoing measures that rewarded political patronage. He also signed the Pendleton Civil Service Act, which created a civil-service system based on merit. He and his navy secretary recommended appropriations that later helped transform the U.S. Navy into one of the world’s great fleets. He failed to win his party’s nomination for a second term.