rheumatoid Vrii-mo-.tokB arthritis Chronic, progressive autoimmune disease causing connective-tissue inflammation, mostly in synovial joints. It can occur at any age, is more common in women, and has an unpredict¬ able course. It usually starts gradually, with pain and stiffness in one or more joints, then swelling and heat. Muscle pain may persist, worsen, or subside. Membrane inflammation and thickening scars joint structures and destroys cartilage. In severe cases, adhesions immobilize and deform the joints, and adjacent skin, bones, and muscles atrophy. If high-dose aspi¬ rin, ibuprofen, and other NSAIDs do not relieve pain and disability, low- dose corticosteroids may be tried. Physical medicine and rehabilitation with heat and then range-of-motion exercises reduce pain and swelling. Orthopedic appliances correct or prevent gross deformity and malfunc¬ tion. Surgery can replace destroyed hip, knee, or finger joints with pros- theses. There is also a juvenile form of the disease.
Rhiannon \hre-'a-non\ Welsh manifestation of the Gaulish horse god¬ dess Epona and the Irish goddess Macha. She is best known from the Mabinogion, in which she makes her appearance on a pale, mysterious steed and meets King Pwyll, whom she marries. Unjustly accused of kill¬ ing her infant son, she was forced to carry people on her back like a horse until she was vindicated by her son’s return.
Rhine, Confederation of the See Confederation of the Rhine
Rhine River German Rhein River, western Europe. Rising in the Swiss Alps, it flows north and west through western Germany to drain through the delta region of The Netherlands into the North Sea. It is 820 mi (1,319 km) long and navigable for 540 mi (870 km). Its many canals connect it with the Rhone, Marne, and Danube river systems. It has been an inter¬ national waterway since 1815 (see Congress of Vienna). It has played a prominent part in German history and legend. During World War II its course was a major line of defense. Major cities along its banks include Basel, Mannheim, Koblenz, Cologne, Duisburg, and Rotterdam.
Rhineland German Rheinland Region of Germany. It is located west of the Rhine River and encompasses the states of Saarland and Rhineland- Palantinate and portions of Baden-Wiirttemberg, Hesse, and North Rhine- Westphalia. The chief city of the Rhineland is Cologne. In the 19th century the Rhineland became the most prosperous area of Germany. After World War I, Allied troops occupied portions of the area on the border with France, and it was the scene of recurrent crises and controversies during the 1920s. In 1936 Adolf Hitler ordered German troops to enter the demilitarized zone of the Rhineland; weak objections by the Allies fore¬ shadowed Hitler’s later annexation of the Sudetenland.
rhinoceros Any of five extant African and Asian species (family Rhi- nocerotidae) of three-toed horned ungulates. One of the largest of all land animals (the white rhinoceros is second only to the elephant), the rhinoc¬
eros is particularly distinguished by one or two horns—growths of kera¬ tin, a fibrous hair protein—on its upper snout. All have thick, virtually hairless skin that, in the three Asian species, forms platelike folds at the shoulders and thighs. Rhinos grow to 8-14 ft (2.5-4.3 m) long and 3-6.5 ft (1.5-2 m) tall; adults weigh 3-5 tons. Most are solitary inhabitants of open grassland, scrub forest, or marsh, but the Sumatran rhino lives in deep forest. The African black rhino browses on succulent plants, the white and great Indian rhinos graze on short grasses, and the Sumatran and Javan rhinos browse on bushes and bamboo. In the second half of the 20th century, the rhinoc¬ eroses were brought to the brink of extinction by hunters, mostly seek¬ ing the horn, which is valued in Asia as an aphrodisiac. The white rhinoceros of Africa is no longer endangered, but the population of the other four species combined is only a few thou¬ sand, almost all of which live on reserves.
rhinovirus \ l ri-n6-'vl-r3s\ Any of a group of picornaviruses capable of causing common colds in humans. The virus is thought to be transmitted to the upper respiratory tract by airborne droplets. Because of the great number of cold viruses, vaccines against them are virtually impossible to develop. See also adenovirus.
rhizome Horizontal underground plant stem capable of producing the upward shoot and downward root systems of a new plant. This capabil¬ ity allows vegetative (asexual) propagation and enables plants to survive an annual unfavourable season underground. In some plants (e.g., water lilies, many ferns, and forest herbs), the rhizome is the only stem of the plant. In such cases, only the leaves and flowers are readily visible.
Rhode Island officially Rhode Island and Providence Plan¬ tations State (pop., 2000: 1,048,319), northeastern U.S. One of the New England states and the smallest U.S. state, it covers 1,212 sq mi (3,139 sq km); its capital is Providence. Rhode Island is bordered by Massachu¬ setts on the north and east, and Connecticut on the west. The Rhode Island Sound on the south is the basis of the state’s fishing industry. The origi¬ nal inhabitants of the area were Narragansett Indians. The first European settlement was in 1636 by Roger Williams and his followers, who were banished from Massachusetts; in 1663 King Charles II granted a charter to Williams. Though it never officially joined the New England colonies in King Philip's War, it suffered greatly when many settlements were burned. It was at the forefront of the fight against British customs laws that led to the American Revolution. An original state of the Union, in 1790 it was the 13th state to ratify the Constitution, agreeing only after the Bill of Rights was included. The state’s original charter remained in effect until Dorr’s Rebellion (see Thomas W. Dorr) in 1842 led to extension of suf¬ frage. The cotton-textile mill built by Samuel Slater in Pawtucket in 1790 initiated the Industrial Revolution in the U.S. Manufacturing is still impor¬ tant to the economy, and products include jewelry and silverware, textiles and clothing, and electrical machinery and electronics.
Rhode Island School of Design (RISD) One of the most eminent fine arts colleges in the U.S., located in Providence, R.I. It was founded in 1877 but did not offer college-level instruction until 1932. It combines professional arts training with a broad liberal arts curriculum, offering bachelor’s and master’s degrees in the design, fine arts, and other fields. Its art museum has extensive collections of American painting and deco¬ rative arts.
Rhodes Greek Rodhos Vr6-,th6s\ Island of Greece. It is the largest island of the Dodecanese group and the most easterly in the Aegean Sea. Its main city, Rhodes (pop., 2001: 53,709), lies at the northern tip of the island. The earliest known settlers were the Dorians c. 1000 bc. During the Classical period the island’s affiliations vacillated between Athens, Sparta, and Persia in attempts to preserve a balance of power. A devas¬ tating earthquake c. 225 bc destroyed the Colossus of Rhodes, one of the Seven Wonders of the World. In the medieval period Rhodes was occu-
African black rhino (Diceros bicornis).
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1616 I Rhodes ► Rhodope Mountains
pied by the Byzantines, Muslims, and Knights of St. John (see Knights of Malta). The knights converted the island into a fortress and held it for two centuries until 1523, when the Turks took control. In 1912 it was taken from Turkey by Italy, and in 1947 it was awarded by treaty to Greece. A year-round tourist industry has brought prosperity to the island.
Rhodes, Alexandre de (b. March 15, 1591, Avignon, France—d. March 5, 1660, Esfahan, Iran) French missionary, the first Frenchman to visit Vietnam. He established a Jesuit mission in the region in 1619 and later estimated that he had converted some 6,700 Vietnamese to Roman Catholicism. Expelled in 1630, he spent 10 years teaching philosophy in Macau before returning, only to be exiled again in 1646. The Vatican sponsored a Vietnamese missionary program in 1658 based on de Rhodes’s ideas, but he himself was sent to Iran (Persia), where he died. He wrote a Vietnamese-Latin-Portuguese dictionary and perfected the romanized script Quoc-ngu (developed by earlier missionaries), which facilitated communicating Christian doctrines to the Vietnamese and increased the literacy rate among the population.