(from the article "nervous system, human") In a fundamental discovery made in 1954, Canadian researchers James Olds and Peter Milner found that stimulation of certain regions of the brain of the rat acted as a reward ...
American inventor and automobile manufacturer, designer of the three-horsepower, curved-dash Oldsmobile, the first commercially successful American-made automobile and the first to use a progressive assembly system, which foreshadowed modern mass-production ... [3 Related Articles]
brigadier general (ret.), U.S. Air Force was a World War II ace fighter pilot who later flew 152 combat missions during the Vietnam War. Olds was perhaps best known for ...
(from the article "Olds, Ransom Eli") American inventor and automobile manufacturer, designer of the three-horsepower, curved-dash Oldsmobile, the first commercially successful American-made automobile and the first to use a progressive assembly system, which foreshadowed modern mass-production ...
(from the article "Olduvai Gorge") The Olduvai fossil beds accumulated in a lake basin between 4 and 9 miles (7 and 15 km) in diameter. The lake is underlain by volcanic rocks of the Pliocene ...
paleoanthropological site in the eastern Serengeti Plain, within the boundaries of the Ngorongoro Conservation Area in northern Tanzania. It is a steep-sided ravine consisting of two branches that have a ... [11 Related Articles]
(from the article "Homo habilis") ...into a gully. Some of the teeth survived, but the cranium was broken into many small fragments; only the top of the braincase, or vault, has been pieced back together. ...
(from the article "Homo habilis") ...gully. Some of the teeth survived, but the cranium was broken into many small fragments; only the top of the braincase, or vault, has been pieced back together. These two ...
(from the article "Homo habilis") Since 1964 more material has been discovered, not only at Olduvai but at other African localities as well. One intriguing specimen is OH 24. This cranium is more complete than ...
(from the article "Homo habilis") ...discovery was reported from Olduvai Gorge in 1986. A jaw with teeth and skull fragments as well as pieces of a right arm and both legs were found. The bones ...
(from the article "Homo habilis") Apart from the original discovery of the jaw, cranial, and hand bones from a juvenile individual called Olduvai Hominid 7 (OH 7), additional fossils from Olduvai have been ascribed to ...
(from the article "Homo erectus") ...the more convincing evidence for the existence of H. erectus in Africa came with the discovery in 1960 of a partial braincase at Olduvai Gorge in Tanzania. This fossil, catalogued ...
the olive family, belonging to the order Lamiales and named for the economically important olive tree (species Olea europaea). A number of plants in the family are of economic or ... [1 Related Articles]
(from the article "gastropod") ...woodland snails of eastern North America (Polygyridae), plus a Neotropical group (Thysanophoridae) and a relict group of Asia (Corillidae).Carnivorous (Oleaciniidae) and herbivorous (Sagdidae) snails of the Neotropical region.Oleaciniidae
(from the article "gastropod") ...(Polygyridae), plus a Neotropical group (Thysanophoridae) and a relict group of Asia (Corillidae).Carnivorous (Oleaciniidae) and herbivorous (Sagdidae) snails of the Neotropical region.Land snails without (Oreohelicidae and...
city, Cattaraugus county, western New York, U.S. It lies along the Allegheny River at the mouth of Olean Creek, 60 miles (97 km) southeast of Buffalo. First settled in 1804 ...
(from the article "Potter") Potter county was organized in 1804 and named for James Potter, a general in the American Revolution. Norwegian violinist Ole Bornemann Bull founded Oleona (located south of present-day Carter Camp) ...
small deciduous tree of Eurasia, about 4.5 to 6 m (15 to 20 feet) high. It has smooth, dark brown branches that often bear spines and narrow, light green leaves ...
(from the article "ulna") ...or trochlear, notch-which articulates with the trochlea of the humerus (upper arm bone) to form the elbow joint. The projection that forms the upper border of this notch is called ...
(from the article "humerus") ...elbow joint, and two projections (epicondyles). The capitulum laterally articulates with the radius; the trochlea, a spool-shaped surface, articulates with the ulna. The two depressions-the olecranon fossa, behind and above ...
any unsaturated hydrocarbon containing one or more pairs of carbon atoms linked by a double bond. The olefins are classified in either or both of the following ways: (1) as ... [23 Related Articles]
(from the article "Common fatty acids in foods") ...unsaturated fatty acids and glycerides to higher-melting saturated products. The process consists of the addition of hydrogen in the presence of a catalyst to the double (unsaturated) bonds. Thus oleic ...
city, south-central Ukraine, on the Inhulets River. Founded as Usivka in the early 18th century, it was renamed Becheyu (also Becha, or Bechka) in the 1750s, Oleksandriysk in 1784, and ...
uppermost of two divisions of the Lower Triassic Series, representing those rocks deposited worldwide during Olenekian time (249.7 million to 245 million years ago) in the Triassic Period. The stage ...
genus of trilobites (extinct arthropods) common in but restricted to Early Cambrian rocks (540 to 520 million years ago) and thus a useful guide fossil for the Early Cambrian. Olenellus ... [1 Related Articles]
river rising on the southern slopes of the Bukochan Ridge on the Central Siberian Plateau and flowing mainly through Sakha (Yakutiya), east-central Russia. The total length of the river is ... [1 Related Articles]
colour lithograph produced by preparing a separate stone by hand for each colour to be used and printing one colour in register over another. The term is most often used ... [2 Related Articles]
(from the article "naval stores") Gum naval stores are derived from the oleoresin, a fluid commonly called crude turpentine, that exudes from incisions made in the living trees. Wood naval stores are obtained by the ...
(from the article "horticulture") Horticulture is divided into the cultivation of plants for food (pomology and olericulture) and plants for ornament (floriculture and landscape horticulture). Pomology deals with fruit and nut crops. Olericulture deals ...
island in the Bay of Biscay, forming part of the Charente-Maritime departement, located off the coast of France south of La Rochelle and north of the Gironde Estuary. Oleron is ...
(from the article "Moustiers faience") Another important Moustiers factory was that of Joseph Olerys, founded in 1738 and active until c. 1793. Olerys introduced polychrome decoration, producing faience in the Berain style painted in purple, ...
Russian prose writer and playwright whose works address the conflict between old and new mentalities in the early years of the Soviet Union. [1 Related Articles]
any of a group of moths in the family Tortricidae (order Lepidoptera) that contains several species with economically destructive larvae. The pale caterpillars roll or tie leaves and feed on ...
(from the article "Heidelberg Catechism") Reformed confession of faith that is used by many of the Reformed churches. It was written in 1562 primarily by Caspar Olevianus, the superintendent of the Palatinate church, and Zacharias ...
structure located in the forebrain of vertebrates that receives neural input about odours detected by cells in the nasal cavity. The axons of olfactory receptor (smell receptor) cells extend directly ... [3 Related Articles]
(from the article "nasal concha") ...chambers of the nasal cavities. They increase the surface area of these cavities, thus providing for rapid warming and humidification of air as it passes to the lungs. In higher ...
(from the article "nervous system, human") Bipolar cells in the nasal mucosa give rise to axons that enter the cranial cavity through foramina in the cribriform plate of the ethmoid bone. These cells and their axons, ...
(from the article "nasal tumour") Olfactory neuroblastoma is a highly malignant tumour that originates in the olfactory (smell) receptor cells, located in the upper rear portion of the nose. This tumour is one of the ...
(from the article "nose") the prominent structure between the eyes that serves as the entrance to the respiratory tract and contains the olfactory organ. It provides air for respiration, serves the sense of smell, ...
protein capable of binding odour molecules that plays a central role in the sense of smell (olfaction). These receptors are common to arthropods, terrestrial vertebrates, fish, and other animals. In ... [2 Related Articles]
(from the article "Langjokull") ...(24 km) wide and covers an area of 395 square miles (1,025 square km). It rises to 4,757 feet (1,450 m) above sea level in the centre and feeds several ...
(from the article "Olgas") ...rising from the desert plains north of the Musgrave Ranges. They occupy an area of 11 square miles (28 square km) within Uluru-Kata Tjuta National Park (established in 1958 as ...
princess who was the first recorded female ruler in Russia and the first member of the ruling family of Kiev to adopt Christianity. She was canonized as the first Russian ... [2 Related Articles]
tors (isolated weathered rocks) in southwestern Northern Territory, Australia, comprising a circular grouping of some 36 red conglomerate domes rising from the desert plains north of the Musgrave Ranges. They ...
(from the article "Jainism") The Jain calendar includes many festivals. Among them is the Shvetambara fasting ceremony, oli, which is celebrated for nine days twice a year (in March-April and September-October) ...
(from the article "conquistador") ...Aztec capital of Tenochtitlan (now Mexico City). Between 1522 and 1524, Michoacan and the Pacific coastal regions were conquered, and in 1524, expeditions led by Pedro de Alvarado and Cristobal ...
third and last major worldwide division of the Paleogene Period (65.5 million to 23 million years ago), spanning the interval between 33.9 million to 23 million years ago. The Oligocene ... [10 Related Articles]
any worm of the subclass Oligochaeta (class Clitellata, phylum Annelida). About 3,500 living species are known, the most familiar of which is the earthworm (q.v.), Lumbricus terrestris. Oligochaetes are common ... [4 Related Articles]
(from the article "nervous system") ...of different neuroglia, neurologists have been able to discern two (in some opinions, three) main groups of neuroglia: (1) astrocytes, subdivided into fibrous and protoplasmic types; (2) oligodendrocytes, subdivided into ...
(from the article "plant breeding") The easiest characters, or traits, to deal with are those involving discontinuous, or qualitative, differences that are governed by one or a few major genes. Many such inherited differences exist, ...
(from the article "pregnancy") True oligohydramnios, a deficiency in amniotic fluid, is a rare condition of unknown cause. It is seen more often in pregnancies that have extended beyond the projected time of delivery. ...
(from the article "protozoan") ...well-developed oral/cytopharyngeal zones; typical genera are Nassula, Paramecium, Frontonia, and hypotrichs, such as Euplotes.Complex oral cilia distinct from the body cilia; oral cavity may be deep, with ciliary structures ...
prolonged intervals between menstrual cycles. Menstruation is the normal cyclic bleeding from the female reproductive tract. Most women of reproductive age menstruate every 25 to 30 days if they are ... [1 Related Articles]
(from the article "industrial polymers, major") In the above structure, n varies from about 2 to 25 repeating units; such low-molecular-weight prepolymers as these are called oligomers. Depending on their average chain length, the prepolymers vary ...
(from the article "sedimentary rock") Clast-supported conglomerates (and orthobreccias) are deposited by highly turbulent water. For example, beach deposits commonly contain lenses and bands of oligomictic orthoconglomerate, composed mainly (95 percent or more) of stable, ...
(from the article "recombinant DNA technology") One method of in vitro mutagenesis is oligonucleotide-directed mutagenesis. A specific point in a sequenced gene is pinpointed for mutation. An oligonucleotide, a short stretch of synthetic DNA of the ...
market situation in which each of a few producers affects but does not control the market. Each producer must consider the effect of a price change on the actions of ... [5 Related Articles]
(from the article "hantavirus") ...Argentina (the Andes virus, carried by Oligoryzomys longicaudatus, a species of pygmy rice rat), and Central America (the Choclo virus, carried by Oligoryzomys fulvescens, ...
(from the article "hantavirus") ...Louisiana (the Bayou virus, carried by the marsh rice rat [Oryzomys palustris]), Chile and Argentina (the Andes virus, carried by Oligoryzomys longicaudatus, a species ...
any carbohydrate of from three to six units of simple sugars (monosaccharides). A large number of oligosaccharides have been prepared by partially breaking down more complex carbohydrates (polysaccharides). Most of ... [4 Related Articles]
(from the article "infertility") ...of the semen. Sperm count is the total number of sperm in the ejaculate; counts vary widely, but values below 20 million are usually considered low. Low sperm count is ...
any spherical to pear-shaped protozoan of the ciliate order Oligotrichida, found in fresh, salt, and brackish water. Body cilia (minute, hairlike projections), when present, are often fused into groups of ...
(from the article "inland water ecosystem") Standing bodies of fresh water are often divided into categories that reflect levels of biological production. Oligotrophic lakes are those that are unproductive: net primary production is only between 50 ...
(from the article "renal system disease") ...three phases: an onset phase, a phase of established acute renal failure, and a recovery phase. In general, but not invariably, the second of these phases is characterized by a ...
city, eastern Pernambuco estado (state), northeastern Brazil. It is located atop a low hill on the Atlantic coast, immediately north of Recife, the state capital. It was ... [3 Related Articles]
(Bassaricyon), any of about four species of small arboreal carnivores of the raccoon family, Procyonidae, found in the jungles of Central and northern South America. Olingos are slender, grayish-brown animals ... [1 Related Articles]
(from the article "Myrtales") ...shrub or treelet that occurs from Bolivia, throughout the Andes, to Costa Rica. Three small families related to Alzateaceae and Crypteronianceae are restricted to Africa: Rhynchocalycaceae; Oliniaceae, found in eastern ...
(from the article "burlesque show") ...patterned after the popular minstrel show. It consisted of three parts: first, a series of songs, coarsely humorous sketches or bits, and comic monologues usually by baggy-pants comics; second, the ...
(from the article "horn") Medieval European ivory horns, imported from Byzantium in the 10th century, were associated with royalty; these ivory (sometimes bone) horns, often richly carved, were called oliphants. The oxhorns of medieval ...
(from the article "Native American") ...federal or dominion authorities. One area of concern has been whether a non-Indian who commits a criminal act while on reservation land can be prosecuted in the tribal court. In ...
British-born Canadian dance educator (b. Aug. 5, 1918, London, Eng.-d. July 12, 2004, St. Catherines, Ont.), became a ballet dancer in London and, after moving to Canada in 1947, opened ... [1 Related Articles]
British author, traveller, and mystic, a controversial figure whose quest to establish a Jewish state in Palestine-"fulfilling prophecy and bringing on the end of the world"-won wide support among both ...
Australian physicist (b. Oct. 8, 1901, Adelaide, Australia-d. July 14, 2000, Canberra, Australia), was an esteemed specialist in high-energy physics at the University of Cambridge's Cavendish Laboratory, where he had ... [1 Related Articles]
(from the article "algae") ...bodies) occasionally found in freshwater or marine environments; fewer than 50 species; Heterosigma, Vacuolaria, and Olisthodiscus.Previously placed in Chrysophyceae; silica-scaled; ...
Russian-born American painter generally identified with the Abstract Expressionist school known as colour field. He was one of the first to use thinned paints in a staining technique to create ... [1 Related Articles]
(from the article "olive shell") any of the marine snails that constitute the family Olividae (subclass Prosobranchia of the class Gastropoda). Fossils of the genus Oliva are common from the Eocene Epoch (57.8 to 36.6 ...
(from the article "Minnesota Twins") Renamed the Twins, the team quickly became contenders in their new home, advancing to the World Series in 1965, with outfielder Tony Oliva and pitcher Jim Kaat joining Killebrew as ...
(from the article "Austria") ...same time, Austria was engaged in the northeast when it intervened in the war between Sweden and Poland (1658) in order to prevent the collapse of Poland. There were some ...
prime minister (1623-43) and court favourite (valido) of King Philip IV of Spain. He attempted to impose a strong centralizing policy and eventually provoked rebellion and his ... [6 Related Articles]
(from the article "ear, human") Some fibres from the ventral cochlear nucleus pass across the midline to the cells of the superior olivary complex, whereas others make connection with the olivary cells of the same ...
(Olea europaea; family Oleaceae), subtropical, broad-leaved, evergreen tree and its edible fruit. The tree, ranging in height from 3 to 12 metres (10 to 40 feet) or more, has numerous ... [4 Related Articles]
(from the article "olive") The olive fruit is classed botanically as a drupe, similar to the peach or plum. Within the stone are one or two seeds. Olives tend to have maximum oil content ...
(from the article "colobus") ...more or less thumbless and can be distinguished by colour: black-and-white colobus (genus Colobus), red colobus (genus Piliocolobus), and olive colobus (genus
(from the article "fruit fly") ...family include the Mexican fruit fly (Anastrepha ludens), which attacks citrus crops; the Oriental fruit fly (Dacus dorsalis), which infests many kinds of subtropical fruits; and the olive fruit fly ...
(from the article "glassware") The second factory of importance, later known as the Olive Glass Works, Gloucester County, New Jersey, was completed in 1781 by former employees of the Wistar Glass Works, the Stanger ...
(from the article "common saturated fatty acids") Olive oil is invariably marketed in undeodorized form. The natural flavour is an important asset, and olive oil, as is true of butter, commands a premium in the market because ...
(from the article "sea turtle") ...of its jellyfish prey, it moves widely throughout the oceans. The shell lengths of few individuals exceed 1.6 metres (5 feet), although some reportedly reach 2.4 metres (8 feet). Adult ...
any of the marine snails that constitute the family Olividae (subclass Prosobranchia of the class Gastropoda). Fossils of the genus Oliva are common from the Eocene Epoch (57.8 to 36.6 ... [1 Related Articles]
(from the article "Italy") ...leadership. "Prodi bis," or Prodi II, as the new executive was nicknamed, became the 62nd Italian government since 1945. As the year wore on, the beleaguered head of the centre-left ...
(from the article "law, philosophy of") The Swedish jurist Axel Hagerstrom insisted that the idea of rules of law as commands is an idea not corresponding with facts. His disciple Karl Olivecrona added that this false ...
(from the article "Portuguese literature") ...of Sebastiao de Carvalho, marquis of Pombal). Henrique da Gama Barros and Antonio de Sousa Silva Costa Lobo followed Herculano on early historical and political topics. The works of Joaquim ...
(from the article "Portuguese literature") ...a sophisticated form with Jose Regio (who was also an outstanding dramatist and religious poet), took new, neorealist directions with the work of Antonio Alves Redol and Carlos de Oliveira. ...
