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  • Uraniidae (insect)

    lepidopteran: Annotated classification: Family Uraniidae (swallowtail moths) Approximately 700 chiefly tropical species; some adults are large, brilliantly iridescent diurnal moths; the Asian Epicopeia (family Epicopeiidae) mimic swallowtail butterflies. Superfamily Drepanoidea Approximately 700 species worldwide in 2 families. Family Drepanidae

  • uraninite (mineral)

    Uraninite, a major ore mineral of uranium, uranium dioxide (UO2). Uraninite usually forms black, gray, or brown crystals that are moderately hard and generally opaque. A variety of uraninite ore that is dense and found in granular masses with a greasy lustre is called pitchblende. Uraninite is

  • uranium (chemical element)

    Uranium (U), radioactive chemical element of the actinoid series of the periodic table, atomic number 92. It is an important nuclear fuel. Uranium constitutes about two parts per million of Earth’s crust. Some important uranium minerals are pitchblende (impure U3O8), uraninite (UO2), carnotite (a

  • Uranium City (Saskatchewan, Canada)

    Uranium City, municipal corporation, centre of the Beaverlodge Lake mining region in extreme northwestern Saskatchewan, Canada. It lies near the north shore of Lake Athabasca. The discovery in the early 1950s and the subsequent mining of uranium ore there by the Eldorado Mining and Refining Company

  • uranium dioxide (chemical compound)

    ceramic composition and properties: Crystal structure: …material shown is urania (uranium dioxide, UO2). In this structure the oxygen anions are bonded to only four cations. Oxides with this structure are well known for the ease with which oxygen vacancies can be formed. In zirconia (zirconium dioxide, ZrO2), which also possesses this structure, a great number…

  • uranium hexafluoride (chemical compound)

    coordination compound: Characteristics of coordination compounds: …molecules is uranium(+6) fluoride, or uranium hexafluoride (UF6). The structural formula of the compound represents the actual arrangement of atoms in the molecules:

  • uranium hydride (chemical compound)

    hydride: Metallic hydrides: Uranium hydride (UH3) is the most important hydride of the actinoid metals. This pyrophoric black powder is prepared by reaction with hydrogen at 300 °C (570 °F). 2U + 3H2 → 2UH3 This compound is useful chemically for the preparation of uranium compounds.

  • uranium processing

    Uranium processing, preparation of the ore for use in various products. Uranium (U), although very dense (19.1 grams per cubic centimetre), is a relatively weak, nonrefractory metal. Indeed, the metallic properties of uranium appear to be intermediate between those of silver and other true metals

  • uranium series (chemical series)

    Uranium series, set of unstable heavy nuclei constituting one of the four radioactive

  • uranium tetrafluoride (chemical compound)

    uranium processing: Conversion and isotopic enrichment: …550° C (1,025° F) produces uranium tetrafluoride (UF4) and water vapour, as in the following reaction:

  • uranium X2 (isotope)

    Kasimir Fajans: …with Otto Gohring, he discovered uranium X2, which is now called protactinium-234m. In 1917 he joined the Institute of Physical Chemistry, Munich, where he rose from associate professor to director. From 1936 to 1957, when he retired, Fajans was a professor at the University of Michigan, Ann Arbor. He became…

  • uranium-233 (chemical isotope)

    fissile material: …naturally occurring uranium), plutonium-239, and uranium-233, the last two being artificially produced from the fertile materials uranium-238 and thorium-232, respectively. A fertile material, not itself capable of undergoing fission with low-energy neutrons, is one that decays into fissile material after neutron absorption within a reactor. Thorium-232 and uranium-238 are the…

  • uranium-234–uranium-238 dating

    Uranium-234–uranium-238 dating, method of age determination that makes use of the radioactive decay of uranium-238 to uranium-234; the method can be used for dating of sediments from either a marine or a playa lake environment. Because this method is useful for the period of time from about

  • uranium-235 (chemical isotope)

    radioactivity: Alpha decay: The existence of uranium-235 in nature rests on the fact that alpha decay to the ground and low excited states exhibits hindrance factors of over 1,000. Thus the uranium-235 half-life is lengthened to 7 × 108 years, a time barely long enough compared to the age of the…

  • uranium-238 (chemical isotope)

    breeder reactor: …a breeder reactor employs either uranium-238 or thorium, of which sizable quantities are available. Uranium-238, for example, accounts for more than 99 percent of all naturally occurring uranium. In breeders, approximately 70 percent of this isotope can be utilized for power production. Conventional reactors, in contrast, can extract less than…

  • uranium-239 (chemical isotope)

    uranium processing: …upon absorbing a neutron, forms uranium-239, and this latter isotope eventually decays into plutonium-239—a fissile material of great importance in nuclear power and nuclear weapons. Another fissile isotope, uranium-233, can be formed by neutron irradiation of thorium-232.

  • uranium–lead dating

    dating: Uranium–lead method: As each dating method was developed, tested, and improved, mainly since 1950, a vast body of knowledge about the behaviour of different isotopic systems under different geologic conditions has evolved. It is now clear that with recent advances the uranium–lead method is superior…

  • uranium-series disequilibrium dating

    dating: Uranium-series disequilibrium dating: The isotopic dating methods discussed so far are all based on long-lived radioactive isotopes that have survived since the elements were created or on short-lived isotopes that were recently produced by cosmic-ray bombardment. The long-lived isotopes are difficult to use on young…

  • uranium-thorium-helium dating

    helium dating: …method is referred to as uranium–thorium–helium dating; if only the alpha-particle emission and helium content are measured, the method is called the alpha-helium radioactive clock. Alpha particles are the nuclei of helium atoms emitted from the nucleus of the radioactive progenitor.

  • uranium-thorium-lead dating

    Uranium-thorium-lead dating, method of establishing the time of origin of a rock by means of the amount of common lead it contains; common lead is any lead from a rock or mineral that contains a large amount of lead and a small amount of the radioactive progenitors of lead—i.e., the uranium

  • Uranographia (work by Bode)

    Johann Elert Bode: Among his other publications was Uranographia (1801), a collection of 20 star maps accompanied by a catalog of 17,240 stars and nebulae. In 1776 he propounded a theory of the solar constitution similar to that developed in 1795 by Sir William Herschel. He gave currency to the empirical rule known…

  • Uranographia (work by Hevelius)

    astronomical map: New constellations: 16th–20th century: In his Uranographia of 1687, the German astronomer Johannes Hevelius devised seven new constellations visible from mid-northern latitudes that are still accepted, including Sextans (the sextant), named for one of his own astronomical instruments. Fourteen additional southern constellations were formed by Nicolas Louis de Lacaille after his…

  • uranography (Judaism)

    Judaism: Early stages to the 6th century ce: …about devils); mythical geography and uranography (description of the heavens); contemplation of the divine manifestations, whose background was the Jerusalem Temple worship and the visions of the moving “throne” (merkava, “chariot”) in the prophecy of Ezekiel; reflection on the double origin of human beings, who are formed of the earth…

  • Uranometria (work by Bayer)

    Johann Bayer: …[Germany]), German astronomer whose book Uranometria (1603) promulgated a system of identifying all stars visible to the naked eye.

  • Uranometria Argentina (work by Gould)

    astronomical map: New constellations: 16th–20th century: Gould’s Uranometria Argentina (1877–79) standardized the list of constellations as they are known today. They divided Ptolemy’s largest constellation, Argo Navis (the ship), into four parts: Vela (the sail), Pyxis (the compass), Puppis (the stern), and Carina (the keel).

  • Uranometria Nova (work by Argelander)

    astronomical map: New constellations: 16th–20th century: Argelander’s Uranometria Nova (1843) and Benjamin A. Gould’s Uranometria Argentina (1877–79) standardized the list of constellations as they are known today. They divided Ptolemy’s largest constellation, Argo Navis (the ship), into four parts: Vela (the sail), Pyxis (the compass), Puppis (the stern), and Carina (the keel).

  • Uranomys ruddi (mammal)

    African spiny mouse: …in this subfamily; these are Rudd’s mouse (Uranomys ruddi), the Congo forest mouse (Deomys ferrugineus), and brush-furred rats (genus Lophuromys).

  • Uranoscopidae (fish)

    perciform: Danger to human life: Especially well-armed are the electric stargazers (Astroscopus; Uranoscopidae), which are capable of discharging up to 50 volts of electricity from the modified muscle tissue just posterior to the eyes; in addition, they possess a venom spine just above the pectoral fins. The venom from uranoscopids has been known to…

  • Uranotheria (mammal)

    mammal: Classification: Uranotherians The following three ungulate orders (Sirenia, Proboscidea, and Hyracoidea) are sometimes grouped together as the order Uranotheria, for they are more closely related to one another than to other ungulates. Order Hyracoidea (hyraxes) 4 species in 1 family. Order

  • uranotherian (mammal)

    mammal: Classification: Uranotherians The following three ungulate orders (Sirenia, Proboscidea, and Hyracoidea) are sometimes grouped together as the order Uranotheria, for they are more closely related to one another than to other ungulates. Order Hyracoidea (hyraxes) 4 species in 1 family. Order

  • Uranus (Greek mythology)

    Uranus, in Greek mythology, the personification of heaven. According to Hesiod’s Theogony, Gaea (Earth), emerging from primeval Chaos, produced Uranus, the Mountains, and the Sea. From Gaea’s subsequent union with Uranus were born the Titans, the Cyclopes, and the Hecatoncheires. Uranus hated his

  • Uranus (planet)

    Uranus, seventh planet in distance from the Sun and the least massive of the solar system’s four giant, or Jovian, planets, which also include Jupiter, Saturn, and Neptune. At its brightest, Uranus is just visible to the unaided eye as a blue-green point of light. It is designated by the symbol ♅.

  • Uranus, Operation (World War II)

    Battle of Stalingrad: …a huge Soviet counteroffensive, code-named Operation Uranus (November 19–23), which had been planned by Generals Georgy Konstantinovich Zhukov, Aleksandr Mikhailovich Vasilevsky, and Nikolay Nikolayevich Voronov. It was launched in two spearheads, some 50 miles (80 km) north and south of the German salient whose tip was at Stalingrad. The counteroffensive…

  • uranyl acetate (chemistry)

    alkali metal: Analytical chemistry of the alkali metals: A modification of the uranyl acetate test (the precipitation of an insoluble sodium salt with uranyl acetate) has been used as a standard test for the presence of sodium. The use of a cobaltinitrite solution permits separation of potassium from sodium by precipitation of the insoluble potassium salt. There…

  • uranyl carbonate (chemistry)

    uranium processing: Leaching: …to form a readily soluble uranyl carbonate complex ion, [UO2(CO3)3]4-.

  • uranyl ion (chemistry)

    mineral deposit: Roll-front deposits: …which state it forms the uranyl ion (UO2)2+. Uranyl compounds tend to be soluble in groundwater, whereas U4+ compounds are not. So long as the groundwater remains oxidizing, uranyl ions are stable and uranium can be transported by groundwater; however, when uranyl ions encounter a reducing agent such as organic…

  • uranyl nitrate (chemistry)

    uranium processing: Refining of yellow cake: …to yield a highly purified uranyl nitrate, UO2(NO3)2.

  • uranyl sulfate (chemistry)

    uranium processing: Leaching: …sulfuric acid to form a uranyl sulfate complex anion, [UO2(SO4)3]4-.

  • Urartian language

    Urartian language, ancient language spoken in northeastern Anatolia and used as the official language of Urartu in the 9th–6th centuries bce. Urartu centred on the district of Lake Van but also extended over the Transcaucasian regions of modern Russia and into northwestern Iran and at times even

  • Urartian religion

    Haldi: …of the ancient kingdom of Urartu, which ruled the plateau around Lake Van, now eastern Turkey, from about 900 to about 600 bc. Haldi was represented as a man, with or without wings, standing on a lion; in the absence of religious texts his attributes are otherwise unknown. A Urartian…

  • Urartu (ancient country, Eurasia)

    Urartu, ancient country of southwest Asia centred in the mountainous region southeast of the Black Sea and southwest of the Caspian Sea. Today the region is divided among Armenia, eastern Turkey, and northwestern Iran. Mentioned in Assyrian sources from the early 13th century bce, Urartu enjoyed

  • urate (chemical compound)

    arthritis: Crystalloid arthritis: …the deposition of needle-shaped monosodium urate crystals in the joint space (urate is a form of uric acid). Initially, gout tends to occur in one joint only, typically the big toe (podagra), though it can also occur in the knees, fingers, elbows, and wrists. Pain, frequently beginning at night, can…

  • Urawa (Japan)

    Saitama: …portion of Saitama city, and Urawa, the southern part of the new city, were roughly equal in size at the time of the merger. Both had been post towns on the Nakasendō highway between Ōsaka and Edo (Tokyo) during the Tokugawa period (1603–1867), and both grew rapidly in the 20th…

  • Urayasu (Japan)

    Urayasu, city, northwestern Chiba ken (prefecture), east-central Honshu, Japan. Lying on a flat plain along Tokyo Bay, it is separated from the city of Tokyo to the west by the Edo River. Urayasu was a thriving fishing village during the Edo (Tokugawa) period (1603–1867) but grew only slowly until

  • Urbain, Georges (French chemist)

    lutetium: …Carl Auer von Welsbach and Georges Urbain, working independently. Urbain derived the name for the element from Lutetia, the ancient Roman name for Paris, to honour his native city. The name lutetium became widely accepted except in Germany, where it was commonly called cassiopeium until the 1950s. One of the…

  • urban anthropology

    anthropology: Urban anthropology: Urban anthropology is the study of cultural systems and identities in cities as well as the various political, social, economic, and cultural forces that shape urban forms and processes. Although anthropologists have studied the city since the 1930s, the label urban anthropology became…

  • Urban Bicycling

    The wheels of fortune continued to turn in favour of the Bicycle in 2015 even as proponents of cycling continued to navigate a complex array of political, cultural, and infrastructural issues. Compelled by climate and health crises as well as the shifting expectations of urban residents,

  • urban blues (music)

    blues: History and notable musicians: …adapted to the more sophisticated urban environment. Lyrics took up urban themes, and the blues ensemble developed as the solo bluesman was joined by a pianist or harmonica player and then by a rhythm section consisting of bass and drums. The electric guitar and the amplified harmonica created a driving…

  • urban climate (meteorology)

    Urban climate, any set of climatic conditions that prevails in a large metropolitan area and that differs from the climate of its rural surroundings. Urban climates are distinguished from those of less built-up areas by differences of air temperature, humidity, wind speed and direction, and amount

  • Urban Community, Ecomuseum of the (museum, Le Creusot-Montceau-les-mines, France)

    museum: Museums and the environment: …the ecomuseum, such as the Ecomuseum of the Urban Community at Le Creusot–Montceau-les-Mines in France. There a bold experiment involves the community as a whole, rather than specialists, in interpreting the human and natural environment, thereby generating a better understanding among its inhabitants of the reasons for cultural, social, and…

  • urban contemporary music (music)

    Urban contemporary music, musical genre of the 1980s and ’90s defined by recordings by rhythm-and-blues or soul artists with broad crossover appeal. Urban contemporary began as an American radio format designed to appeal to advertisers who felt that “black radio” would not reach a wide enough

  • Urban Cowboy (film by Bridges [1980])

    James Bridges: Bridges also scored big with Urban Cowboy (1980), a formulaic but entertaining story about a young Texas construction worker (John Travolta) who lets his marriage to independent Sissy (Debra Winger) disintegrate while he struggles to be accepted in the world of Gilley’s, the famed Houston honky-tonk, with its mechanical bull…

  • urban culture (sociology)

    Urban culture, any of the behavioral patterns of the various types of cities and urban areas, both past and present. Research on urban cultures naturally focuses on their defining institution, the city, and the lifeways, or cultural forms, that grow up within cities. Urban scholarship has steadily

  • urban design

    Urban planning, design and regulation of the uses of space that focus on the physical form, economic functions, and social impacts of the urban environment and on the location of different activities within it. Because urban planning draws upon engineering, architectural, and social and political

  • urban ecosystem

    Urban ecosystem, any ecological system located within a city or other densely settled area or, in a broader sense, the greater ecological system that makes up an entire metropolitan area. The largest urban ecosystems are currently concentrated in Europe, India, Japan, eastern China, South America,

  • urban forestry (forestry)

    forestry: Urban forestry: Urban forestry, which is the management of publicly and privately owned trees in and adjacent to urban areas, has emerged as an important branch of forestry. Urban forests include many different environments such as city greenbelts; street and utility rights-of-way; forested watersheds of municipal…

  • urban geography (geography)

    geography: Human geography as locational analysis: New subdisciplines—notably urban geography—came rapidly to the fore, as systematic specialisms displaced regional courses from the core of many curricula. Other parts of the discipline—economic, social, political, and historical—were influenced by the theoretical and quantitative revolutions. What became known as a “new” human geography was created, initially…

  • urban geology (science)

    geology: Other areas of application: of engineering, environmental, and urban geology are broadly concerned with applying the findings of geologic studies to construction engineering and to problems of land use. The location of a bridge, for example, involves geologic considerations in selecting sites for the supporting piers. The strength of geologic materials such as…

  • urban growth boundary

    urban sprawl: Smart growth communities: …employing smart growth principles are urban growth boundaries. Urban growth boundaries involve the drawing of mapped lines that separate areas designated for urban expansion from open space and, beyond that, agriculture. The boundary is typically kept in place for a period of 20 years to encourage development within the city…

  • urban guerrilla warfare

    guerrilla warfare: The Cold War period: …was the media-heightened impact of urban guerrilla warfare, and such its potential danger to civilized society, that some observers believed “urban terrorism” should be classified as a new genre of warfare. But terrorist tactics, urban or rural, even the most extreme, have always been integral to guerrilla and counterguerrilla warfare—indeed…

  • Urban I, Saint (pope)

    Saint Urban I, ; feast day May 25), pope from 222 to 230. Succeeding that of St. Calixtus I, his pontificate occurred within the reign of the Roman emperor Severus Alexander, a time of peace for the church. His baptism of St. Cecilia’s husband, St. Valerian, is fictitious. He was buried in the

  • Urban II (pope)

    Urban II, head of the Roman Catholic Church (1088–99) who developed ecclesiastical reforms begun by Pope Gregory VII, launched the Crusade movement, and strengthened the papacy as a political entity. Odo was born of noble parents about 1035 in the Champagne region of France. After studies in

  • Urban III (pope)

    Urban III, pope from 1185 to 1187. Of noble birth, he was made cardinal and archbishop of Milan in 1182 by Pope Lucius III, whom he succeeded on Nov. 25, 1185, and from whom he inherited an imperial diplomatic crisis that harassed his entire pontificate. On Jan. 27, 1186, Henry VI, son of the Holy

  • Urban Indian Relocation Program (United States history)

    Native American: Reorganization: …of Indian Affairs instituted the Urban Indian Relocation Program. Initiated within the bureau in 1948 and supported by Congress from the 1950s on, the relocation program was designed to transform the predominantly rural native population into an assimilated urban workforce. The bureau established offices in a variety of destination cities,…

  • Urban Institute of Ireland (building, Dublin, Ireland)

    Yvonne Farrell and Shelley McNamara: …Housing (2000), Dublin, and the Urban Institute of Ireland (2002), Dublin. The latter was a new addition to University College Dublin campus, which mostly comprises 19th-century school buildings. Although Grafton Architects’ geometric building appears modern next to its neighbours, it reflects their materials, featuring unique applications of brick, concrete, and…

  • Urban IV (pope)

    Urban IV, pope from 1261 to 1264. Urban was of humble origin. He was first a priest at Lyon and then professor of canon law at Paris before being elevated to the bishopric of Verdun in 1253. Two years later he was made patriarch of Jerusalem by Pope Alexander IV. Despite not having been made a

  • Urban League (American organization)

    National Urban League, American service agency founded for the purpose of eliminating racial segregation and discrimination and helping African Americans and other minorities to participate in all phases of American life. By the late 20th century more than 110 local affiliated groups were active

  • Urban Legend (film by Blanks [1998])

    Jared Leto: …up with the slasher movie Urban Legend (1998). He also appeared in Terrence Malick’s star-packed war drama The Thin Red Line (1998). Leto played club regular Angel Face in the cult classic Fight Club (1999) and had major roles in Girl, Interrupted (1999) and American Psycho (2000).

  • Urban Light (art installation by Burden)

    Chris Burden: …from Erector set parts, and Urban Light (2008), a permanent—and now iconic—installation of some 200 restored antique lampposts outside the Los Angeles County Museum of Art. In 2013 he was the subject of a large-scale retrospective, “Chris Burden: Extreme Measures,” organized by the New Museum, in New York. He received…

  • urban mapping (sociology)

    sociology: Ecological patterning: …Chicago School’s urban research involved mapping locations. These included locations of land values, specific populations (racial, ethnic, or occupational), ethnic succession in neighbourhoods, residences of persons who committed certain crimes, or zones with a high incidence of divorce and desertion. Data-collection methods included participant observation, life histories, case studies, historical…

  • Urban Militia (Spanish military faction)

    Spain: Moderates, progressives, and the generals: Their instrument was the Urban Militia. General Espartero used his military faction and his supporters among the younger progresista politicians and their artisan followers in the great cities to oust María Cristina and establish himself as regent (1841–43). Espartero proved a disappointment to the radical progresistas, who now allied…

  • urban music (music)

    Urban contemporary music, musical genre of the 1980s and ’90s defined by recordings by rhythm-and-blues or soul artists with broad crossover appeal. Urban contemporary began as an American radio format designed to appeal to advertisers who felt that “black radio” would not reach a wide enough

  • urban planning

    Urban planning, design and regulation of the uses of space that focus on the physical form, economic functions, and social impacts of the urban environment and on the location of different activities within it. Because urban planning draws upon engineering, architectural, and social and political

  • Urban Question, The (work by Castells)

    urban culture: Definitions of the city and urban cultures: …City, 1973), Manuel Castells (The Urban Question, 1977), and other scholars influenced by Marxism caused a major shift in the conception of urban cultural roles. Although they mainly worked on cities in advanced capitalist cultures, their approach had wide relevance. Rather than looking outward from the city to the…

  • urban realism (arts)

    African American literature: The advent of urban realism: Despite the enormous outpouring of creativity during the 1920s, the vogue of black writing, black art, and black culture waned markedly in the early 1930s as the Great Depression took hold in the United States. African American pundits in the 1930s and ’40s…

  • Urban Reform Law (1960, Cuba)

    Cuba: Housing: The Urban Reform Law of 1960 prohibited landlords from renting urban real estate, and families soon began buying homes by paying the current rental sum for between 5 and 20 years. Many families have acquired titles to houses and apartments in this fashion, and the rest…

  • urban renewal

    Urban renewal, comprehensive scheme to redress a complex of urban problems, including unsanitary, deficient, or obsolete housing; inadequate transportation, sanitation, and other services and facilities; haphazard land use; traffic congestion; and the sociological correlates of urban decay, such as

  • urban revolution (anthropology)

    Urban revolution, in anthropology and archaeology, the processes by which agricultural village societies developed into socially, economically, and politically complex urban societies. The term urban revolution was introduced by the archaeologist V. Gordon Childe. Childe identified 10 formal

  • Urban Robot (Japanese architectural firm)

    Toyo Ito: …he established his own practice, Urban Robot (URBOT), in Tokyo, initially focusing on residential and other small-scale projects. One of his most notable early designs was the White U house (1976) in Tokyo. Intended as a place of solace and retreat for Ito’s recently widowed sister, the house—built in the…

  • urban servitude (property law)

    servitude: …to another) include various rights-of-way; urban servitudes (i.e., those established for convenience) include building rights in neighbouring properties, such as drainage and encroachment rights, and rights to light, support, and view.

  • urban society (sociology)

    Urban culture, any of the behavioral patterns of the various types of cities and urban areas, both past and present. Research on urban cultures naturally focuses on their defining institution, the city, and the lifeways, or cultural forms, that grow up within cities. Urban scholarship has steadily

  • urban sprawl

    Urban sprawl, the rapid expansion of the geographic extent of cities and towns, often characterized by low-density residential housing, single-use zoning, and increased reliance on the private automobile for transportation. Urban sprawl is caused in part by the need to accommodate a rising urban

  • urban transportation

    Our Future Eco-Cities: Beyond Automobile Dependence: …of the biggest problems is transport. Motor vehicles fill the streets of every city from Los Angeles to Lagos, from Beijing to Berlin, causing chronic congestion, chaotic parking, air pollution, noise, crippled bus systems, traffic deaths, and despoiled public environments, which make walking and cycling, the most sustainable modes, extremely…

  • urban tunnel (building and construction)

    tunnels and underground excavations: Settlement damage and lost ground: …rights-of-way, the dominant concern in urban tunneling is the need to avoid intolerable settlement damage to adjoining buildings. While this is rarely a problem in the case of modern skyscrapers, which usually have foundations extending to rock and deep basements often extending below the tunnel, it can be a decisive…

  • Urban V, Blessed (pope)

    Blessed Urban V, ; feast day December 19), pope from 1362 to 1370. Of noble birth, he joined the Benedictines, later teaching law at Avignon. He became abbot of Saint-Germain, Auxerre, in 1352 and of Saint-Victor, Marseille, in 1361. On Sept. 28, 1362, he was elected successor to Innocent VI and

  • Urban VI (pope)

    Urban VI, pope from 1378 to 1389 whose election sparked the Western Schism (1378–1417). Archbishop first of Acerenza (1363) and then of Bari (1377), he became papal chancellor for Pope Gregory XI, whom he was elected to succeed on April 8, 1378. This election of an Italian appeased the Romans, who

  • Urban VII (pope)

    Urban VII, pope from Sept. 15 to Sept. 27, 1590. Of noble birth, he held several key church offices, including papal ambassador to Spain (until 1572), cardinal priest (1583), and inquisitor general (1586). Known for his charity and piety, he was elected pope on Sept. 15, 1590, but died of malaria

  • Urban VIII (pope)

    Urban VIII, pope from 1623 to 1644. The son of an aristocratic Florentine family, Barberini filled many distinguished church appointments. He served as papal legate in France (1601) and was simultaneously appointed (1604) archbishop of Nazareth and nuncio to Paris. Pope Paul V made him cardinal in

  • Urban Wildlife: Carnivores Come to the City

    In July 2016 Chicago’s City Council approved a measure that tacitly protected urban wildlife; the measure called on animal-control officials not to disturb coyotes found within Chicago unless they acted aggressively or otherwise threatened people. As urban environments continued to expand

  • urban yellow fever (pathology)

    yellow fever: The course of the disease: …the yellow fever virus: (1) urban, or classical, yellow fever, in which transmission is from person to person via the “domestic” (i.e., urban-dwelling) Aedes aegypti mosquito; (2) jungle, or sylvatic, yellow fever, in which transmission is from a mammalian host (usually a monkey) to humans via any one of a…

  • Urban, Joseph (Austrian architect and stage designer)

    theatre: Developments in the United States: …was represented by the Viennese Joseph Urban, who when he went to the Boston Opera before World War I took with him an entire atelier of draftsmen and scenic artists. Urban moved into musical comedy and eliminated the acreage of painted vistas and box sets that had been manufactured by…

  • Urban, Keith (Australian singer, songwriter, and guitarist)

    Keith Urban, New Zealand-born Australian singer, songwriter, and guitarist who earned recognition both inside and outside the country music sphere for his pop-rock influences and honest lyrics. Urban moved with his family from New Zealand to Queensland, Australia, when he was two years old.

  • Urban, Keith Lionel (Australian singer, songwriter, and guitarist)

    Keith Urban, New Zealand-born Australian singer, songwriter, and guitarist who earned recognition both inside and outside the country music sphere for his pop-rock influences and honest lyrics. Urban moved with his family from New Zealand to Queensland, Australia, when he was two years old.

  • Urban, Wilbur Marshall (American philosopher)

    religious experience: Study and evaluation: Hocking, and Wilbur M. Urban represented an idealist tradition in interpreting religion, stressing the concepts of purpose, value, and meaning as essential for understanding the nature of God. Naturalist philosophers, of whom John Dewey was typical, have focused on the “religious” as a quality of experience and…

  • Urbana (Ohio, United States)

    Urbana, city, Champaign county, west-central Ohio, U.S., in a stock-raising and farming area, 40 miles (64 km) northeast of Dayton. Laid out in 1805 by Col. William Ward of Virginia, it became the county seat in the same year and grew after a training camp was established there by Gen. William Hull

  • Urbana (Illinois, United States)

    Urbana, city, seat (1833) of Champaign county, east-central Illinois, U.S. Urbana is contiguous with Champaign (west), about 135 miles (220 km) southwest of Chicago. The two cities are often called Champaign-Urbana. The area was first settled in 1822, and in 1833 the city was founded as the county

  • Urbani, Carlo (Italian epidemiologist)

    Carlo Urbani, Italian epidemiologist (born Oct. 19, 1956, Castelplanio, Italy—died March 29, 2003, Bangkok, Thai.), recognized that the SARS (severe acute respiratory syndrome) outbreak was an epidemic and raised the alarm, allowing the disease to be somewhat contained, before dying himself of S

  • urbanisation

    Urbanization, the process by which large numbers of people become permanently concentrated in relatively small areas, forming cities. The definition of what constitutes a city changes from time to time and place to place, but it is most usual to explain the term as a matter of demographics. The

  • Urbanist Poor Clare (religious order)

    Poor Clare: …came to be called the Urbanist Poor Clares or officially the Order of St. Clare (O.S.C.), whereas those communities who continued to observe the stricter rule of St. Clare (as revised in 1253) became known as the Primitives.

  • urbanization

    Urbanization, the process by which large numbers of people become permanently concentrated in relatively small areas, forming cities. The definition of what constitutes a city changes from time to time and place to place, but it is most usual to explain the term as a matter of demographics. The

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