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  • acidity (chemistry)

    buffer: …the ionization constant of acetic acid and the expressions in brackets are the concentrations of the respective substances. The hydrogen ion concentration of the buffer solution is dependent on the relative amounts of acetic acid and acetate ion (or sodium acetate) present, known as the buffer ratio. The addition of…

  • acidity exponent (chemistry)

    acid–base reaction: Acid–base equilibria: …quantity pKa, sometimes called the acidity exponent, and defined by the relation pKa = −log10Ka. Values of pKa are generally of a more convenient magnitude.

  • acidity function (chemistry)

    acid–base reaction: Concentrated aqueous acids: …is commonly measured by the acidity function, H0, a quantity measured by the effect of the solvent on a basic indicator I. It is defined by H0 + pKih+ − log10 [IH+]/[I] and becomes equal to the pH in dilute solution. The acidity function H0 frequently is found to be…

  • acidophile (biology)

    extremophile: …organisms may be described as acidophilic (optimal growth between pH 1 and pH 5); alkaliphilic (optimal growth above pH 9); halophilic (optimal growth in environments with high concentrations of salt); thermophilic (optimal growth between 60 and 80 °C [140 and 176 °F]); hyperthermophilic (optimal growth above 80 °C [176 °F]);…

  • acidophilic organism (biology)

    extremophile: …organisms may be described as acidophilic (optimal growth between pH 1 and pH 5); alkaliphilic (optimal growth above pH 9); halophilic (optimal growth in environments with high concentrations of salt); thermophilic (optimal growth between 60 and 80 °C [140 and 176 °F]); hyperthermophilic (optimal growth above 80 °C [176 °F]);…

  • acidosis (pathology)

    Acidosis, abnormally high level of acidity, or low level of alkalinity, in the body fluids, including the blood. There are two primary types of acidosis: respiratory acidosis and metabolic acidosis. Respiratory acidosis results from inadequate excretion of carbon dioxide from the lungs. This may be

  • acids and bases, proton theory of (chemistry)

    Brønsted–Lowry theory, a theory, introduced independently in 1923 by the Danish chemist Johannes Nicolaus Brønsted and the English chemist Thomas Martin Lowry, stating that any compound that can transfer a proton to any other compound is an acid, and the compound that accepts the proton is a base.

  • Acier Noir (typeface)

    Cassandre: …he designed two other typefaces, Acier Noir (1935) and Piegnot (1937). In 1939 he abandoned poster art and henceforth devoted himself to designing stage sets and to painting.

  • Acier, Michel Victor (French sculptor)

    pottery: Porcelain: …by the figure modelling of Michel Victor Acier, who came to the factory to share the position of Modellmeister with Kändler in 1764. From 1774 to 1814 the Neoclassical style was increasingly used, and the designs of Sèvres and of Wedgwood (Wedgwoodarbeit) were copied.

  • Aciéries Réunies de Burbach-Eich-Dudelange (Luxembourger company)

    Luxembourg: Manufacturing and trade: …the late 1970s ARBED (Aciéries Réunies de Burbach-Eich-Dudelange) SA was Luxembourg’s only remaining steelmaker. In 2001 ARBED merged with the Spanish company Aceralia and the French company Usinor to form Arcelor, which subsequently joined Mittal to create ArcelorMittal, the world’s largest steel company at the time of its formation…

  • Acilia Repetundarum, Lex (Roman law)

    epigraphy: Ancient Rome: …bce; pieces of the laws Lex Acilia Repetundarum (123 bce) and Lex Agraria (111 bce) were found in the 16th century on opposite sides of what was once a large bronze tablet; the local laws of the town of Bantia (on the borderlands of Lucania and Apulia in southern Italy)…

  • Acilius Glabrio (Roman consul)

    Marcus Porcius Cato: …Cato served with distinction under Manius Acilius Glabrio at Thermopylae in the war against the Seleucid king Antiochus III. Shortly thereafter he included Glabrio in his denunciation of the supporters of the Scipios. He then attacked Lucius Scipio and Scipio Africanus the Elder and broke their political influence. This success…

  • acinar cell (anatomy)

    pharmaceutical industry: Isolation of insulin: …destroyed by enzymes from the acinar cells. By this time Banting had enlisted the support of Charles H. Best, a fourth-year medical student. Together they tied off the pancreatic ducts through which acinar cells release the digestive enzymes. This insult caused the acinar cells to die. Subsequently, the remainder of…

  • Acinipo (Spain)

    Ronda, town, Málaga provincia (province), in the Andalusia comunidad autónoma (autonomous community), southern Spain. It lies in the Ronda Mountains west of Málaga city. The town is situated on two hills divided by a deep ravine (El Tajo de Ronda) containing the Grande River, which is an affluent

  • Acinonyx (mammal)

    feline: Evolution and classification: Acinonychinae Genus Acinonyx (cheetah) 1 almost exclusively African species. Assorted ReferencesAmazon Rain Forestclassification and characteristics

  • Acinonyx jubatus (mammal)

    Cheetah, (Acinonyx jubatus), one of the world’s most-recognizable cats, known especially for its speed. Cheetahs’ sprints have been measured at a maximum of 114 km (71 miles) per hour, and they routinely reach velocities of 80–100 km per hour while pursuing prey. Nearly all the cheetahs remaining

  • Ačinsk (Russia)

    Achinsk, city, Krasnoyarsk kray (region), south-central Russia. It lies along the Chulym River, which is a tributary of the Ob. It was founded in 1621 and chartered in 1782. Important as a river-road transfer point until rail lines were constructed, it gained economic importance when an alumina

  • acinus (anatomy)

    respiratory disease: Morphological classification of respiratory disease: …terminal bronchiole opens into an acinus, so called because the structure resembles a cluster of grapes, and from this point onward the gas-exchanging portion of the lung is reached. The alveoli, or air sacs, which are divided into groups or lobules by fibrous partitions, or septa, are small hexagonal structures…

  • Acipenser fulvescens (fish)

    sturgeon: Distribution: The lake, or rock, sturgeon (A. fulvescens) of North America occurs in the Mississippi River valley, Great Lakes, and Canada and may weigh more than 90 kg (200 pounds). The white, Oregon, or Sacramento sturgeon (A. transmontanus) occurs on the Pacific coast and is the largest…

  • Acipenser guldenstadtii (fish)

    sturgeon: Distribution: The Russian sturgeon, A. guldenstadtii, is one of the most valuable species inhabiting the rivers of Russia and occurs eastward to Lake Baikal. It is about the same size as the common sturgeon and is found particularly in the rivers feeding the Black and Caspian seas.…

  • Acipenser huso (fish)

    Hausen, large species of sturgeon

  • Acipenser oxyrhynchus (fish)

    sturgeon: Distribution: …considered a separate species (A. oxyrhynchus) by some authorities, occurs along the east coast of North America. The length of these fishes is generally to about 3 metres (10 feet); their weight can reach about 227 kg (500 pounds).

  • Acipenser ruthenus (fish)

    caviar: …the golden eggs of the sterlet, was formerly reserved for the table of the tsar; more recently it found its way to the tables of Soviet dignitaries and that of the shah of Iran. Lesser grades of caviar, made from broken or immature eggs, are more heavily salted and compressed.…

  • Acipenser sinensis (fish)

    sturgeon: Conservation status: The Chinese sturgeon is thought to be the species most at risk, because its population declined nearly 98 percent between 1973 and 2010. The species decline has been associated with water pollution in the Yangtze and dam construction that has blocked access to or changed the…

  • Acipenser stellatus (fish)

    sturgeon: Distribution: The stellate, or star, sturgeon, A. stellatus, occurs in the rivers of the Black and Caspian seas and of the Sea of Azov. It has a long pointed snout like the sterlet, and its flesh, caviar, and isinglass are highly valued.

  • Acipenser sturio (fish)

    sturgeon: Distribution: The common Old World sturgeon (Acipenser sturio) occurs from Scandinavia to the Mediterranean. A very similar, closely related form, considered a separate species (A. oxyrhynchus) by some authorities, occurs along the east coast of North America. The length of these fishes is generally to

  • Acipenser transmontanus (fish)

    sturgeon: Distribution: The white, Oregon, or Sacramento sturgeon (A. transmontanus) occurs on the Pacific coast and is the largest of the North American sturgeons, weighing up to 820 kg (1,800 pounds).

  • Acipenseridae (fish)

    Sturgeon, (family Acipenseridae), any of about 29 species of fishes of the family Acipenseridae (subclass Chondrostei), native to temperate waters of the Northern Hemisphere. Most species live in the ocean and ascend rivers (possibly once in several years) to spawn in spring or summer; a few others

  • Acipenseriformes (fish order)

    fish: Annotated classification: Order Acipenseriformes (sturgeons and paddlefishes) Almost no internal ossification; scales as large scutes in isolated rows (Acipenseridae); snout enlarged and tactile (Polyodontidae); median fins chondrostean in having more fin rays than basal elements; tail heterocercal. Length (sturgeons) up to 6 metres (roughly 20 feet), weight to…

  • Acireale (Italy)

    Acireale, town and episcopal see, eastern Sicily, Italy, on terraces above the Ionian Sea at the foot of Mount Etna, 7 miles (11 km) northeast of Catania. Known as Aquilia by the Romans, the town was called Reale by Philip IV of Spain in 1642. The first part of its name is derived from the ancient

  • Acis (Greek mythology)

    Acis, in the Greek mythology of Ovid, the son of Faunus (Pan) and the nymph Symaethis. He was a beautiful shepherd of Sicily, the lover of the Nereid Galatea. His rival, Polyphemus the Cyclops, surprised them together and crushed him to pieces with a rock. His blood, gushing forth from beneath, was

  • Acis and Galatea (serenata by Handel)

    serenata: …genre is Handel’s pastoral serenata Acis and Galatea (c. 1718).

  • Acis et Galatée (ballet by Fokine)

    Michel Fokine: …performance by his pupils, was Acis et Galatée, based on an ancient Sicilian legend. Fokine’s enthusiasm for antiquity owed nothing in origin to the “free dance” ideas of the American dancer Isadora Duncan, although her appearance in Russia in 1905 greatly consolidated his own views. In 1905 he also composed…

  • Acis in Oxford (work by Finch)

    Robert Finch: …as did a later work, Acis in Oxford (1961), a series of meditations inspired by a performance of G.F. Handel’s dramatic oratorio Acis and Galatea. Dover Beach Revisited (1961), treating the World War II evacuation of Dunkirk and issues of faith, contains 11 variations on Matthew Arnold’s poem. In another…

  • aCJD

    Creutzfeldt-Jakob disease: Types: acquired (aCJD). Both sCJD and aCJD may be further divided into subtypes. The most common sCJD subtype is sCJDMM1. Subtypes of aCJD include iatrogenic (iCJD) and variant (vCJD) forms of the disease (kuru is sometimes considered a third subtype of aCJD).

  • AcK (isotope)

    francium: …an isotope of francium (francium-223) that was formerly called actinium K (AcK) and is a member of the actinium decay series. Though it is the longest-lived isotope of francium, francium-223 has a half-life of only 22 minutes. Thirty-four isotopes of francium with masses between 199 and 232 have been…

  • Ack libertas, tu ädla tingh (work by Wivallius)

    Lars Wivallius: …1632 and translates as “Ah, Liberty, Thou Noble Thing”) and love of nature (most notably the majestic “Klagovisa över denna torra och kalla vår” [1642; “Dirge over This Dry and Cold Spring”], in which the poet laments the season that he encountered upon his release from Kajaneborg).

  • ackee (plant)

    Ackee, (Blighia sapida), tree of the soapberry family (Sapindaceae) native to West Africa, widely cultivated throughout tropical and subtropical regions for its edible fruit. Ackee and salt fish is a popular dish in the Caribbean and is the national dish of Jamaica. Taken to the Caribbean area with

  • Acker, Kathy (American author)

    Kathy Acker, American novelist whose writing style and subject matter reflect the so-called punk sensibility that emerged in the 1970s. Acker studied classics at Brandeis University and the University of California, San Diego. Her early employment ranged from clerical work to performing in

  • Ackerley, J. R. (British writer and editor)

    J.R. Ackerley, British novelist, dramatist, poet, and magazine editor known for his eccentricity. Ackerley’s education was interrupted by his service in World War I, during which he was captured and imprisoned for eight months in Germany. He graduated from Magdalen College, Cambridge, in 1921. He

  • Ackerley, Joe Randolph (British writer and editor)

    J.R. Ackerley, British novelist, dramatist, poet, and magazine editor known for his eccentricity. Ackerley’s education was interrupted by his service in World War I, during which he was captured and imprisoned for eight months in Germany. He graduated from Magdalen College, Cambridge, in 1921. He

  • Ackerman, Diane (American author)

    Diane Ackerman, American writer whose works often reflect her interest in natural science. Ackerman was educated at Pennsylvania State University (B.A., 1970) and Cornell University, Ithaca, N.Y. (M.F.A., 1973; M.A., 1976; Ph.D., 1978). From 1980 to 1983 she taught English at the University of

  • Ackerman, Edward A. (American geographer)

    geography: Geography as a science: a new research agenda: …well to the war effort: Edward A. Ackerman, a professor of geography at the University of Chicago from 1948 to 1955 (and later head of the Carnegie Foundation), claimed that those working in the U.S. government’s intelligence service had only a weak understanding of their material and portrayed them as…

  • Ackerman, Forrest J (American writer and editor)

    Forrest J Ackerman, American writer and editor (born Nov. 24, 1916, Los Angeles, Calif.—died Dec. 4, 2008, Los Angeles), championed the burgeoning genre of science fiction as both an author and a fan and was credited with coining the term “sci-fi.” Ackerman developed an early affection for science

  • Ackermann aus Böhmen, Der (work by Johannes von Tepl)

    Johannes von Tepl: 1400; Death and the Ploughman), the first important prose work in the German language.

  • Ackermann system (mechanics)

    truck: Steering: Steering is always by the Ackermann system, which provides a kingpin for each front wheel. Maximum cramp angle of the front wheels is about 35 degrees. The minimum turning radius is dependent on the wheelbase. A few vehicles have been built with two steering axles in the front.

  • Ackermann, Konrad Ernst (German actor and manager)

    Konrad Ernst Ackermann, actor-manager who was a leading figure in the development of German theatre. Conflicting accounts exist of Ackermann’s early adult years. He was probably not a trained scientist and surgeon, as has been widely reported, but was instead a soldier—and later an officer—in the

  • Ackermann, Louise-Victorine (French poet)

    Louise-Victorine Ackermann, French poet who is best-known for works characterized by a deep sense of pessimism. Educated by her father in the philosophy of the Encyclopédistes, she traveled to Berlin in 1838 to study German and there married (1843) Paul Ackermann, an Alsatian philologist. Two years

  • Ackermann, Wilhelm (German logician)

    history of logic: Propositional and predicate logic: …Theoretical Logic”) by Hilbert and Wilhelm Ackermann.

  • Ackland-Snow, Brian (British production designer and art director)
  • Ackoli (work by Holub)
  • Ackroyd, Peter (British author, biographer, critic and scholar)

    Peter Ackroyd, British novelist, critic, biographer, and scholar whose technically innovative novels present an unconventional view of history. Ackroyd graduated from Clare College, Cambridge (M.A., 1971), and then attended Yale University for two years. In 1973 he returned to England and worked as

  • Aclla Cuna (Inca religion)

    Chosen Women, in Inca religion, women who lived in temple convents under a vow of chastity. Their duties included the preparation of ritual food, the maintenance of a sacred fire, and the weaving of garments for the emperor and for ritual use. They were under the supervision of matrons called Mama

  • ACLU (American organization)

    American Civil Liberties Union (ACLU), organization founded by Roger Baldwin and others in New York City in 1920 to champion constitutional liberties in the United States. The ACLU works to protect Americans’ constitutional rights and freedoms as set forth in the U.S. Constitution and its

  • ACM (international organization)

    Association for Computing Machinery (ACM), international organization for computer science and information technology professionals and, since 1960, institutions associated with the field. Since 1966 ACM has annually presented one or more individuals with the A.M. Turing Award, the most prestigious

  • Acmaeidae (gastropod family)

    gastropod: Classification: …in rocky shallow waters (Acmaeidae and Patellidae). Superfamily Trochacea Small to large spiral shells in shallow to deep ocean waters, often brightly coloured, with or without heavy shell ornamentation; Trochidae (top shells), Turbinidae (turban shells), and Phasianellidae (pheasant shells

  • Acme Colored Giants (American sports team)

    baseball: Segregation: …during 19th century were the Acme Colored Giants, who represented Celoron, New York, in the Iron and Oil Leagues in 1898.

  • Acmeists (Russian poets)

    Acmeist, member of a small group of early-20th-century Russian poets reacting against the vagueness and affectations of Symbolism. It was formed by the poets Sergey Gorodetsky and Nikolay S. Gumilyov. They reasserted the poet as craftsman and used language freshly and with intensity. Centred in S

  • acmite (mineral)

    aegirine: In this series, the name acmite is given to crystals with the composition NaFeSi2O6 as well as to the reddish brown or greenish black pointed crystals approximating that composition. Aegirine generally is restricted to the dark green to greenish black, blunt crystals of the same composition. For detailed physical properties,…

  • ACNA

    Anglican Church in North America, Anglican church formed in 2009 in Bedford, Texas. Its founders were theological traditionalists who had seceded from the Episcopal Church in the United States of America (ECUSA) and the Anglican Church of Canada. Beginning in the 1990s, disputes about the validity

  • acne (dermatology)

    Acne, any inflammatory disease of the sebaceous, or oil, glands of the skin. There are some 50 different types of acne. In common usage, the term acne is frequently used alone to designate acne vulgaris, or common acne, probably the most prevalent of all chronic skin disorders. Acne vulgaris

  • acne vulgaris (dermatology)

    childhood disease and disorder: Disorders associated with adolescence: Acne vulgaris (common acne) is a prevalent skin condition that has its onset during adolescence. At puberty, androgenic stimulation of the skin’s sebaceous (oil) glands (which empty into the canals of the hair follicles) causes increased production of the fatty substance sebum. In susceptible individuals,…

  • ACO (international organization)

    North Atlantic Treaty Organization: Organization: …states, subsumes two strategic commands: Allied Command Operations (ACO) and Allied Command Transformation (ACT). ACO is headed by the SACEUR and located at Supreme Headquarters Allied Powers Europe (SHAPE) in Casteau, Belgium. ACT is headquartered in Norfolk, Virginia, U.S. During the alliance’s first 20 years, more than $3 billion worth…

  • Acochlidacea (gastropod order)

    gastropod: Classification: Order Acochlidacea Three families with visceral mass longer than foot; 4 species in fresh water; a few with sexes in separate animals; size minute. Order Philinoglossacea No head appendages; gill lacking; no external shell; 2 families. Order Anaspidea Shell reduced

  • Acoela (flatworm order)

    flatworm: Annotated classification: Order Acoela Exclusively marine; mouth present; pharynx simple or lacking; no intestine; without protonephridia, oviducts, yolk glands, or definitely delimited gonads; about 200 species. Order Neorhabdocoela Saclike linear intestine; protonephridia and oviducts usually present; gonads few, mostly compact; nervous system generally with 2 longitudinal

  • acoelomate (biology)

    animal: Acoelomates: Flatworms (phyla Platyhelminthes, Nemertea, and Mesozoa) lack a coelom, although nemerteans have a fluid-filled cavity at their anterior, or head, end, which is used to eject the proboscis rapidly. The lack of a fluid-filled cavity adjacent to the muscles reduces the extent to which…

  • Acoemetae (Byzantine monks)

    Acoemeti, monks at a series of 5th- to 6th-century Byzantine monasteries who were noted for their choral recitation of the divine office in constant and never interrupted relays. Their first monastery, at Constantinople, was founded in about 400 by St. Alexander Akimetes, who, after long study of

  • Acoemeti (Byzantine monks)

    Acoemeti, monks at a series of 5th- to 6th-century Byzantine monasteries who were noted for their choral recitation of the divine office in constant and never interrupted relays. Their first monastery, at Constantinople, was founded in about 400 by St. Alexander Akimetes, who, after long study of

  • Acolhua (people)

    Texcoco: …Valley of Mexico by the Acolhuas, a pre-Columbian people of the Nahuatl-speaking group of tribes, which gained mastery of the valley after the collapse of the Toltec hegemony in the mid-12th century ad. The rulers of Texcoco were the first among Nahuatl tribal leaders to establish their rule over Anáhuac…

  • Acoli (people)

    Acholi, ethnolinguistic group of northern Uganda and South Sudan. Numbering more than one million at the turn of the 21st century, they speak a Western Nilotic language of the Eastern Sudanic branch of the Nilo-Saharan family and are culturally and historically related to their traditional enemies,

  • acolyte (religion)

    Acolyte, (from Greek akolouthos, “server,” “companion,” or “follower”), in the Roman Catholic church, a person is installed in a ministry in order to assist the deacon and priest in liturgical celebrations, especially the eucharistic liturgy. The first probable reference to the office dates from

  • Acoma (people)

    Ancestral Pueblo culture: Zuni, Acoma, and Laguna. As farmers, Ancestral Pueblo peoples and their nomadic neighbours were often mutually hostile; this is the source of the term Anasazi, a Navajo word meaning “ancestors of the enemy,” which once served as the customary scientific name for this group.

  • Acoma (pueblo, New Mexico, United States)

    Acoma, Indian pueblo, Valencia county, west-central New Mexico, U.S. The pueblo lies 55 miles (89 km) west-southwest of Albuquerque and is known as the “Sky City.” Its inhabitants live in terraced dwellings made of stone and adobe atop a precipitous sandstone butte 357 feet (109 metres) high. They

  • Acominatus, Michael (Byzantine historian)

    Michael Choniates, Byzantine humanist scholar and archbishop of Athens whose extensive Classical literary works provide the principal documentary witness to the political turbulence of 13th-century Greece after its occupation by the Western Crusaders. Having studied at Constantinople (Istanbul)

  • Acominatus, Nicetas (Byzantine historian)

    Nicetas Choniates, Byzantine statesman, historian, and theologian. His chronicle of Byzantium’s humiliations during the Third and Fourth Crusades (1189 and 1204) and his anthology of 12th-century theological writings constitute authoritative historical sources for this period and established him

  • Acomys (rodent)

    African spiny mouse, (genus Acomys), any of more than a dozen species of small to medium-sized rodents characterized by the harsh, inflexible spiny hairs of their upperparts. African spiny mice have large eyes and ears and scaly, nearly bald tails that are shorter than or about as long as the body.

  • Acomys cahirinus (mammal)

    African spiny mouse: …golden spiny mouse and the Cairo spiny mouse (A. cahirinus).

  • Acomys cilicicus (mammal)

    African spiny mouse: The most restricted is A. cilicicus, which is known only from a single locality in southern Turkey.

  • Acomys kempi (mammal)

    African spiny mouse: …species native to East Africa, Kemp’s spiny mouse (A. kempi) and Percival’s spiny mouse (A. percivali), possess the ability to slough off patches of skin when attempting to escape capture from predators. The wounds that remain, which may be painful in appearance, may shrink dramatically within the first 24 hours…

  • Acomys percivali (mammal)

    African spiny mouse: kempi) and Percival’s spiny mouse (A. percivali), possess the ability to slough off patches of skin when attempting to escape capture from predators. The wounds that remain, which may be painful in appearance, may shrink dramatically within the first 24 hours after the injury. They are covered…

  • Acomys russatus (mammal)

    African spiny mouse: The golden spiny mouse (Acomys russatus), found from Egypt to Saudi Arabia, is one of the largest, with a body up to 25 cm (9.8 inches) long and a shorter tail of up to 7 cm. The Cape spiny mouse (A. subspinosus) of South Africa is…

  • Acomys subspinosus (mammal)

    African spiny mouse: The Cape spiny mouse (A. subspinosus) of South Africa is one of the smallest, with a body up to 10 cm long and a tail of less than 2 cm. Depending upon the species, fur covering the upperparts may be gray, grayish yellow, brownish red, or…

  • Aconcagua River (river, Chile)

    Aconcagua River, river in central Chile. It rises in the northwestern foothills of Mount Aconcagua of the Andes Mountains and flows westward from the Argentine border area to enter the Pacific Ocean north of the city of Viña del Mar after a course of 120 miles (190 km). Much of the Chilean trackage

  • Aconcagua, Cerro (mountain, Argentina)

    Mount Aconcagua, mountain in western Mendoza province, west-central Argentina, on the Chilean border. It is the highest point in the Western Hemisphere. Aconcagua lies in the Southern Andes Mountains; although its peak is in Argentina, its western flanks build up from the coastal lowlands of Chile,

  • Aconcagua, Mount (mountain, Argentina)

    Mount Aconcagua, mountain in western Mendoza province, west-central Argentina, on the Chilean border. It is the highest point in the Western Hemisphere. Aconcagua lies in the Southern Andes Mountains; although its peak is in Argentina, its western flanks build up from the coastal lowlands of Chile,

  • Aconcagua, Río (river, Chile)

    Aconcagua River, river in central Chile. It rises in the northwestern foothills of Mount Aconcagua of the Andes Mountains and flows westward from the Argentine border area to enter the Pacific Ocean north of the city of Viña del Mar after a course of 120 miles (190 km). Much of the Chilean trackage

  • Aconcio, Giacomo (Italian religious reformer)

    Jacobus Acontius, advocate of religious toleration during the Reformation whose revolt took a more extreme form than that of Lutheranism. Acontius served as secretary to Cristoforo Madruzzo, a liberal cardinal. When the more conservative Paul IV became pope, Acontius repudiated Roman Catholic

  • aconitase (enzyme)

    metabolism: Formation of coenzyme A, carbon dioxide, and reducing equivalent: …and isocitrate—remain closely associated with aconitase, the enzyme that catalyzes the isomerization process, and that most of the cis-aconitate is not released from the enzyme surface but is immediately converted to isocitrate.

  • aconitate (chemical compound)

    metabolism: Formation of coenzyme A, carbon dioxide, and reducing equivalent: …from citrate to form cis-aconitate and then the re-addition of water to cis-aconitate in such a way that isocitrate is formed. It is probable that all three reactants—citrate, cis-aconitate, and isocitrate—remain closely associated with aconitase, the enzyme that catalyzes the isomerization process, and that most of the cis-aconitate is…

  • aconite (common name of several plants)

    Aconite, any member of two genera of perennial herbs of the buttercup family (Ranunculaceae): Aconitum, consisting of summer-flowering poisonous plants (see monkshood), and Eranthis, consisting of spring-flowering ornamentals (see winter

  • aconitine (drug)

    monkshood: Major species: …species contain the powerful poison aconitine. The common monkshood, or friar’s cap (A. napellus), native to mountain slopes in Europe and east to the Himalayas, has been the most important source of this drug, which in ancient times was administered to criminals and has been used in minute amounts for…

  • Aconitum (plant)

    Monkshood, (genus Aconitum), genus of more than 200 species of showy perennial herbs of the buttercup family (Ranunculaceae). They occur in the north temperate zone, usually in partial shade and in rich soil. Some species are cultivated as ornamental plants, and several are used in traditional

  • Aconitum carmichaelii (plant)

    monkshood: Major species: …‘Sparks variety’ monkshood (Aconitum henryi), Carmichael’s monkshood (A. carmichaelii), and southern blue monkshood (A. uncinatum). All species contain the powerful poison aconitine. The common monkshood, or friar’s cap (A. napellus), native to mountain slopes in Europe and east to the Himalayas, has been the most important source of this drug,…

  • Aconitum henryi (plant)

    monkshood: Major species: …are cultivated in gardens, including ‘Sparks variety’ monkshood (Aconitum henryi), Carmichael’s monkshood (A. carmichaelii), and southern blue monkshood (A. uncinatum). All species contain the powerful poison aconitine. The common monkshood, or friar’s cap (A. napellus), native to mountain slopes in Europe and east to the Himalayas, has been the most

  • Aconitum napellus (plant)

    monkshood: Major species: The common monkshood, or friar’s cap (A. napellus), native to mountain slopes in Europe and east to the Himalayas, has been the most important source of this drug, which in ancient times was administered to criminals and has been used in minute amounts for reducing fever…

  • Aconitum uncinatum (plant)

    monkshood: Major species: carmichaelii), and southern blue monkshood (A. uncinatum). All species contain the powerful poison aconitine. The common monkshood, or friar’s cap (A. napellus), native to mountain slopes in Europe and east to the Himalayas, has been the most important source of this drug, which in ancient times was…

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    Tucumán: …province is occupied by the Sierra del Aconquija, which consists of northeast-southwest–trending outlying ridges of the Andes Mountains with elevations of 8,000 to 18,000 feet (2,400 to 5,500 metres). The eastern part of the province, by contrast, is flat, alluvial, and agriculturally fertile. Tucumán owes its prosperity to the Sierra…

  • Acontius (Greek legendary figure)

    Acontius, in Greek legend, a beautiful youth of the island of Ceos. During the festival of Artemis at Delos, Acontius saw and loved Cydippe, a girl of a rich and noble family. He wrote on an apple the words “I swear to wed Acontius” and threw it at her feet. She picked it up and mechanically read

  • Acontius, Jacobus (Italian religious reformer)

    Jacobus Acontius, advocate of religious toleration during the Reformation whose revolt took a more extreme form than that of Lutheranism. Acontius served as secretary to Cristoforo Madruzzo, a liberal cardinal. When the more conservative Paul IV became pope, Acontius repudiated Roman Catholic

  • Aconzio, Giacomo (Italian religious reformer)

    Jacobus Acontius, advocate of religious toleration during the Reformation whose revolt took a more extreme form than that of Lutheranism. Acontius served as secretary to Cristoforo Madruzzo, a liberal cardinal. When the more conservative Paul IV became pope, Acontius repudiated Roman Catholic

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