-
Delphinium bakeri (plant)
Annual larkspurs (sometimes separated as the genus Consolida) include the common rocket larkspur (D. ajacis or C. ambigua) and its varieties, up to 60 centimetres (2 feet) tall, with bright blue, pink, or white flowers on branching stalks. Perennial larkspurs, which tend toward blue flowers but vary to pink, white, red, and yellow, include a puzzling assemblage of species,.......
-
Delphinium tricorne (plant species)
Annual larkspurs (sometimes separated as the genus Consolida) include the common rocket larkspur (D. ajacis or C. ambigua) and its varieties, up to 60 centimetres (2 feet) tall, with bright blue, pink, or white flowers on branching stalks. Perennial larkspurs, which tend toward blue flowers but vary to pink, white, red, and yellow, include a puzzling assemblage of species,.......
-
Delphinus (constellation)
small constellation in the northern sky at about 21 hours right ascension and 10° north in declination. The brightest star in Delphinus is Rotanev, with a magnitude of 3.63. The four brightest stars form a diamond-shaped asterism called “Job’s Coffin.” In ...
-
Delphinus delphis (mammal)
Dolphins are popularly noted for their grace, intelligence, playfulness, and friendliness to humans. The most widely recognized species are the common and bottlenose dolphins (Delphinus delphis and Tursiops truncatus). The bottlenose, characterized by a “built-in smile” formed by the curvature of its mouth, has become a familiar performer in......
-
Delray (Florida, United States)
city, Palm Beach county, southeastern Florida, U.S. It lies along the Atlantic Ocean about 20 miles (30 km) south of West Palm Beach. Settlers from Michigan arrived in 1894 and began farming. Soon after, Japanese se...
-
Delray Beach (Florida, United States)
city, Palm Beach county, southeastern Florida, U.S. It lies along the Atlantic Ocean about 20 miles (30 km) south of West Palm Beach. Settlers from Michigan arrived in 1894 and began farming. Soon after, Japanese se...
-
Delrin (chemical compound)
Also called polyoxymethylene (POM) or simply acetal, polyacetal has the simplest structure of all the polyethers. It is manufactured in a solution process by anionic or cationic chain-growth polymerization of formaldehyde (H2C=O), a reaction analogous to vinyl polymerization. By itself, the polymer is unstable and reverts to monomer on heating to 120° C (250°......
-
Delsarte, François (French acting teacher)
The difficulty of solving the problem is illustrated by the work of the 19th-century French teacher François Delsarte, whose influence was widespread not only in France but also in the United States. Delsarte became dissatisfied with routine acting techniques. He observed their mechanical and stultifying character and realized that under the stress of natural instinct or emotion, the......
-
Delsberg (Switzerland)
capital of Jura canton, northwestern Switzerland, situated in a wide valley at the confluence of the Sorne and Birse rivers. First mentioned in historical records in 727, Delémont was annexed by the prince-bishops of Basel in the 11th century for use as a summer residence. Seized by France in 1793, the town was given to Bern in 1815. Delémont became the capital of ...
-
Delsberg Valley (region, Switzerland)
Annual precipitation increases to the south and west, reaching more than 80 inches (2,030 mm) on Mount Risouz and Mount Tendre; but the Delsberg Valley and the north-facing corridor of the Ergolz River (Liestal) receive less than 40 inches (1,000 mm). The climate is of the maritime-continental transitional type: it is rawer on the Jura heights, milder in the protected valleys and on the......
-
Delsemme, Armand H. (American astronomer)
An average heuristic model for the elemental abundances of the cometary nucleus was developed by the American astronomer Armand H. Delsemme in 1982. Delsemme computed the H∶C∶N∶O∶S ratios from ultraviolet and visual observations of atomic and molecular species in bright comets detected during the 1970s and deduced the abundances of metals from the chondritic composition...
-
Delta (launch vehicle)
American three-stage space-launch vehicle; its development began in 1959. The first version was capable of placing a 480-pound (220-kilogram) payload into a 300-mile (480-kilometre) orbit. In the early 1960s, Delta launched TIROS weather satellites, Echo 1, and the Telstar, Relay, and Syncom communication satellites. An improved Delta with a more powerful first stage and capable of placing 1,000 ...
-
Delta (Utah, United States)
city, Millard county, west-central Utah, U.S. Delta is one of the few Utah towns to have been founded in the 20th century with little involvement from the Mormon church, which tightly controlled settlement in the region. Originally an agricultural cooperative called Melville, founded in 1906, the community...
-
Delta (submarine class)
...miles. In 1967 the first of the Soviet Union’s 8,000-ton Yankee-class submarines were delivered, which carried 16 SS-N-6 missiles of 1,300-nautical-mile range. These were followed a decade later by Delta-class vessels fitted with 16 SS-N-18 missiles. Each SS-N-18 had a range of 3,500 nautical miles. In 1982 the Soviet Union began to deploy its Typhoon class, of 18,500 tons displacement a...
-
Delta (state, Nigeria)
state, southern Nigeria. It is bounded by Edo state to the north, Anambra state to the east, Rivers state to the southeast, Bayelsa state to the south, the Bight of Benin of the Atlantic Ocean to the west, and Ondo...
-
Delta (British Columbia, Canada)
district municipality, southwestern British Columbia, Canada. It is situated in the southern Vancouver metropolitan area, between the Fraser River delta and Boundary Bay (an arm of the ...
-
delta (river system component)
low-lying plain that is composed of stream-borne sediments deposited by a river at its mouth....
-
Delta (cell surface molecule)
...of vertebrates, neurons arise from a simple tube of neuroepithelium, the cells of which possess a surface receptor called Notch. These cells also possess another cell surface molecule called Delta that can bind to and activate Notch on adjacent cells. Activation of Notch initiates a cascade of intracellular events that results in suppression of Delta production and suppression of......
-
delta agent
Infection with hepatitis D virus (HDV), also called the delta agent, can occur only in association with HBV infection, because HDV requires HBV to replicate. Infection with HDV may occur at the same time infection with HBV occurs, or HDV may infect a person already infected with HBV. The latter situation appears to give rise to a more......
-
Delta Air Corporation (American company)
American airline incorporated on Dec. 31, 1930, as Delta Air Corporation, which adopted the current name in 1945. Engaged initially in agricultural dusting operations in the southern United States and in Mexico, it progressed, especi...
-
Delta Air Lines, Inc. (American company)
American airline incorporated on Dec. 31, 1930, as Delta Air Corporation, which adopted the current name in 1945. Engaged initially in agricultural dusting operations in the southern United States and in Mexico, it progressed, especi...
-
Delta Amacuro (state, Venezuela)
estado (state), northeastern Venezuela. It is bounded by the Atlantic Ocean on the northeast, Guyana on the southeast, and the Venezuelan states of Bolívar on the south and Monagas on the west. The state consists of one of the largest swampy deltas in the world, through which the 26 distributa...
-
delta bond
...by the cylindrically symmetrical overlap of two d orbitals. There are also two π bonds formed by the overlap of two appropriately orientated d orbitals. The new feature is the δ bond, which is formed by the face-to-face overlap of two parallel d orbitals and has a distinctly different symmetry with respect to the internuclear axis than the other two types of.....
-
delta cell (anatomy)
...cells) may reside in only a fraction of the chain—for example, in a four- or five-amino-acid sequence. In other instances the entire chain must be intact to achieve this purpose. For example, delta (D) cells, which produce a hormone known as somatostatin, are dispersed throughout the whole gastrointestinal tract. Somatostatin has inhibiting effects on the production of acid in the......
-
Delta Cephei (star)
prototype star of the class of Cepheid variables, in the constellation Cepheus. Its apparent visual magnitude at minimum is 4.34 and at maximum 3.51, changing in a regular cycle of about five days and nine hours. Its variations in brightness were discovered in 1784 by the English amateur astronomer John Goodricke...
-
delta connection (electronics)
...also sum to zero at every instant, the three windings can be connected in series—a′ to b, b′ to c, and c′ to a—to form a delta connection. The output can then be transmitted using only three conductors connected to the three junction points. Other advantages of the three-phase system will become evident in the......
-
Delta Dagger (aircraft)
...included the first fighters intended from the outset to carry guided air-to-air missiles and the first supersonic all-weather fighters. Some were only marginally supersonic, notably the U.S. Convair F-102 Delta Dagger, an all-weather interceptor that was the first operational “pure” delta fighter without a separate horizontal stabilizer. Other aircraft included the Grumman F11F......
-
Delta Ibibio (people)
...branch of the Niger-Congo language family. The Ibibio comprise the following major divisions: Efik, Northern (Enyong), Southern (Eket), Delta (Andoni-Ibeno), Western (Anang), and Eastern (the Ibibio proper)....
-
delta iron (mining)
Three true allotropes of iron in its pure form occur. Delta iron, characterized by a body-centred-cubic crystal structure, is stable above a temperature of 1,390° C (2,534° F). Below this temperature there is a transition to gamma iron, which has a face-centred-cubic (or cubic close-packed) structure and is paramagnetic (capable ...
-
Delta of Venus: Erotica (work by Nin)
...her lyrical style, and her psychological insight. Some dismissed her concern with her own fulfillment as self-indulgent and narcissistic. Opinion was further divided by the posthumous Delta of Venus: Erotica (1977) and later collections of previously unpublished erotic stories written on commission during the financially lean years of the early 1940s. Her other works of......
-
Delta Orionis (star)
...Arabic and are frequently derived from translations of the Greek descriptions. The stars of Orion illustrate the various derivations: Rigel, from rijl al-Jawzah, “Leg of Orion,” Mintaka, the “Belt,” and Saiph, the “Sword,” all follow the Ptolemaic figure; Betelgeuse, from yad al-Jawzah, is an alternative non-Ptolemaic description meaning.....
-
Delta Plan (engineering project, Netherlands)
in the southwestern Netherlands, a giant flood-control project that closed off the Rhine, Maas, and Schelde estuaries with dikes linking the islands of Walcheren, Noord-Beveland, Schouwen, Goeree, and Voorne and created what amounts to several freshwater lakes that are free of tides. Devised by the Dutch engineer Johan van Veen, the plan acquired great urgency after a catastrophic ...
-
Delta Project (engineering project, Netherlands)
in the southwestern Netherlands, a giant flood-control project that closed off the Rhine, Maas, and Schelde estuaries with dikes linking the islands of Walcheren, Noord-Beveland, Schouwen, Goeree, and Voorne and created what amounts to several freshwater lakes that are free of tides. Devised by the Dutch engineer Johan van Veen, the plan acquired great urgency after a catastrophic ...
-
delta ray (physics)
in physics, any atomic electron that has acquired sufficient energy by recoiling from a charged particle passing through matter to force, in turn, some dozens of electrons out of other atoms along its own trajectory....
-
delta state (physics)
...than protons and neutrons. For example, the spins of the three quarks can be arranged so that they do not cancel. In this case they form short-lived resonance states, which have been given the name delta, or Δ. The deltas have spins of 32, and the up and down quarks combine in four possible configurations—uuu,......
-
Delta, the (region, Mississippi, United States)
In the northwestern part of the state, the great fertile crescent called the Delta is the old floodplain of the Yazoo and Mississippi rivers, comprising some 6,250 square miles (16,200 square km) of black alluvial soil several feet deep. Once subject to disastrous floods, the land is now protected by levee and reservoir systems....
-
delta wave (brain wave)
...waves become extremely slow. Such is also the case when a person is in a deep coma. Other abnormal conditions are associated with particular EEG patterns. For example, irregular slow waves known as delta waves arise from the vicinity of a localized area of brain damage....
-
delta wing (aeronautics)
The wing planform is the shape it forms when seen from above. Delta wings are formed in the shape of the Greek letter delta (Δ); they are triangular wings lying at roughly a right angle to the fuselage. The supersonic Concorde featured delta wings....
-
Delta Works (engineering project, Netherlands)
in the southwestern Netherlands, a giant flood-control project that closed off the Rhine, Maas, and Schelde estuaries with dikes linking the islands of Walcheren, Noord-Beveland, Schouwen, Goeree, and Voorne and created what amounts to several freshwater lakes that are free of tides. Devised by the Dutch engineer Johan van Veen, the plan acquired great urgency after a catastrophic ...
-
delta-aminolevulinate dehydratase (gene)
...varies widely and depends not only on the extent of environmental or occupational exposure but also on certain genetic factors. For example, a variation that occurs in a gene known as ALAD (delta-aminolevulinate dehydratase) results in the production of an enzyme called ALAD2, which has an abnormally high binding affinity for lead. Both the normal enzyme, known as ALAD1, and......
-
delta-wave (brain wave)
...waves become extremely slow. Such is also the case when a person is in a deep coma. Other abnormal conditions are associated with particular EEG patterns. For example, irregular slow waves known as delta waves arise from the vicinity of a localized area of brain damage....
-
Deltadromeus agilis (dinosaur)
Sereno journeyed to Morocco in 1995, where team member Gabrielle Lyon, whom he married in 1996, discovered the predator Deltadromeus agilis while excavating Cretaceous sediments. The theropod was determined to be among the swiftest dinosaurs yet discovered on the basis of its delicate, narrow frame. The expedition also brought to light the relatively complete skull of a specimen......
-
Deltatheridium (extinct mammal genus)
a genus of extinct mammals found as fossils in rocks from Upper Cretaceous times (about 100–65.5 million years ago) of Asia and, questionably, North America. Deltatheridium was a small insectivorous mammal about the size of a small rat...
-
Deltawerken (engineering project, Netherlands)
in the southwestern Netherlands, a giant flood-control project that closed off the Rhine, Maas, and Schelde estuaries with dikes linking the islands of Walcheren, Noord-Beveland, Schouwen, Goeree, and Voorne and created what amounts to several freshwater lakes that are free of tides. Devised by the Dutch engineer Johan van Veen, the plan acquired great urgency after a catastrophic ...
-
deltoid (anatomy)
large, triangular muscle that covers the shoulder and serves mainly to raise the arm laterally. The deltoid, as it is commonly known, originates on the outer front third of the clavicle (collarbone) and the lower margin of the spine of the scapula (shoulder blade). Its fibres unite to form a thick tendon that inserts at the...
-
deltoideus muscle (anatomy)
large, triangular muscle that covers the shoulder and serves mainly to raise the arm laterally. The deltoid, as it is commonly known, originates on the outer front third of the clavicle (collarbone) and the lower margin of the spine of the scapula (shoulder blade). Its fibres unite to form a thick tendon that inserts at the...
-
Deluc, Jean André (Swiss-British geologist and meteorologist)
Swiss-born British geologist and meteorologist whose theoretical work was influential on 19th-century writing about meteorology....
-
Delucia, Felice (American gangster)
Chicago gangster who was considered “the brains” behind the operations of Al Capone and Capone’s successors, Frank Nitti and Tony Accardo. He was the Chicago representative in the formation of the national crime syndicate in 1934, led by ...
-
Deluge, The (painting by Allston)
...At this point, what was obviously an impetuous and brooding strain in Allston’s temperament found expression by depicting nature in the darker, more destructive moods dear to Turner. “The Deluge” (1804; Metropolitan Museum of Art, New York City) is a typical......
-
DeLuise, Dom (American comic actor)
Aug. 1, 1933Brooklyn, N.Y.May 4, 2009Santa Monica, Calif.American comic actor who stole the show with broad and funny characterizations in dozens of movies, especially in association with director Mel Brooks and actor Burt Reynolds. DeLuise began his career on the stage and in children...
-
DeLuise, Dominick (American comic actor)
Aug. 1, 1933Brooklyn, N.Y.May 4, 2009Santa Monica, Calif.American comic actor who stole the show with broad and funny characterizations in dozens of movies, especially in association with director Mel Brooks and actor Burt Reynolds. DeLuise began his career on the stage and in children...
-
delusion (psychology)
in psychology, a rigid system of beliefs with which a person is preoccupied and to which the person firmly holds, despite the logical absurdity of the beliefs and a lack of supporting evidence. Delusions are symptomatic of such mental disorders as paranoia, schizophrenia, and major depression...
-
Delvalle, Eric Arturo (president of Panama)
...in secret. The population was increased by Jewish immigrants from the West Indies (notably from Curaçao) in the mid-19th century. Panama had the Western Hemisphere’s first Jewish president, Eric Arturo Delvalle (del Valle), who served in the 1980s....
-
Delvaux, André (Belgian filmmaker)
Belgian filmmaker (b. March 21, 1926, Heverlee, Belg.—d. Oct. 4, 2002, Valencia, Spain), was widely regarded as the founder of the Belgian national cinema. A musician and teacher, Delvaux made his first short film, Nous étions treize (1955), with his students. Its success led him to make a series of television documentarie...
-
Delvaux, Paul (Belgian painter)
Belgian Surrealist painter and printmaker whose canvases typically portray transfixed nudes and skeletons in mysterious settings....
-
Delvigne, Henri-Gustave (French officer and inventor)
French army officer and inventor who designed innovative rifles and helped introduce the cylindrical bullet....
-
dema deity (New Guinean mythology)
any of several mythical ancestral beings of the Marind-Anim of southern New Guinea, the centre of a body of mythology called the dema deity complex. The decisive act in dema myths is the slaying of a dema (ancestral) deity by the ancestral tribe. This act brings about the transition from the ancestral world to the human one. In many ancie...
-
Demades (Athenian statesman)
Athenian orator and diplomat who rose from humble origins to a leading place in politics through his vigorous speeches and shrewd ability to fathom popular opinion. Demades opposed Demosthenes’ attempt to arouse the Athenians against Philip II of Macedonia, but he fought against the Macedonians at the Battle of Chaeronea (338) and was taken prisoner. On his release he hel...
-
demagnetization (physics)
Demagnetization and magnetic anisotropy. As far as domain rotation is concerned, there are two important factors to be considered, demagnetization and magnetic anisotropy (exhibition of different magnetic properties when measured along axes in different directions). The first of these concerns the shape of a magnetized specimen. Any magnet generates a magnetic field in the space......
-
Demak (historical kingdom, Indonesia)
The conflict apparently began with the determination of the coastal rulers of the Islamic sultanate of Demak in the first half of the 16th century to rule over a great Javanese kingdom. Especially as their harbours grew richer and their dynasties older and more confident, the coastal princes came to see themselves not only as Muslim leaders but as Javanese royalty. Their pretensions are......
-
Deman, Esther Boise Van (American archaeologist)
American archaeologist and the first woman to specialize in Roman field archaeology. She established lasting criteria for the dating of ancient constructions, which advanced the serious study of Roman architecture....
-
Deman, Ralph Henry Van (United States general)
American intelligence officer, called “the father of American military intelligence.”...
-
demand (economics)
in economics, relationship between the quantity that producers wish to sell at various prices and the quantity of a commodity that consumers wish to buy....
-
demand assigned multiple access (communications)
...area-of-coverage beams for broadcasting and small area-of-coverage “spot beams” for point-to-point communications. By switching between these beams upon request—a process known as demand assigned multiple access (DAMA)—multibeam satellites can link widely distributed mobile and fixed users that cannot be linked economically by optical fibre cables or earthbound radio...
-
demand certificate of deposit (finance)
a receipt from a bank acknowledging the deposit of a sum of money. Among the common types are demand certificates of deposit and time certificates of deposit. Demand certificates of deposit are payable on demand but do not draw interest; they are used primarily by contractors as evidence of good faith when submitting a bid or as a guaranty......
-
demand curve (economics)
in economics, a graphic representation of the relationship between product price and the quantity of the product demanded. It is drawn with price on the vertical axis of the graph and quantity demanded on the horizontal axis. With few exceptions, the demand curve is delineated as sloping downward from left to right because price and quantity demanded are inversely related (i.e.,...
-
demand forecasting
This activity is carried on in conjunction with the firm’s marketing staff and is used to obtain a better idea of the logistic needs of the next planning period. These needs include both delivery to customers and receipt of raw materials or components for assembly. Because the logistics staff is involved with order processing, it also h...
-
demand pacemaker (medical device)
...pacemaker may be altered by the physician, but once set it will continue to generate an electric pulse at regular intervals. Most are set at 70 to 75 beats per minute. More-recent devices are synchronous, or demand, pacemakers that trigger heart contractions only when the normal beat is interrupted. Most pacemakers of this type are designed to generate a pulse when the natural ......
-
demanding reaction (chemistry)
...the catalyst was fired in vacuo at 900 °C (1,600 °F), the percentage dispersion remaining at 35 percent in both cases. Such structure-sensitive catalytic reactions have been called “demanding reactions.” The gain in selectivity appears to be largely because of a reduction in the rate of hydrogenolysis. Since other studies have shown that heating in vacuo to 900 ...
-
Demansia textilis (snake)
...mice, and ground-dwelling birds. They are alert, fast-moving, highly venomous snakes that are quite dangerous to humans. Brown snakes are found over most of Australia. The best-known species is the eastern brown snake (P. textilis), which grows to about 2 metres (7 feet). Other species in the genus are the western brown snake (P. nuchalis) and the dugite (P. affinis)....
-
Demantius, Christoph (German composer)
Dialogues in this vein were also cultivated successfully by Christoph Demantius, whose anthology of 1609 contains examples of memorable beauty and charm. In his Jungfrew, ich het ein’ Bitt’ an euch (Maiden, I have a Request for You), Demantius allows one four-part choir to represent the girl and the other the boy in a conversation full of innocent affection and honest c...
-
demantoid
...beautiful being yellowish (termed topazolite, because of its resemblance to topaz) and yellowish green or emerald-green (Uralian emeralds, or demantoid). Titanium may extensively replace both the iron and the silicon, as in schorlomite, or may simply produce a black colour, as in melanite. Andradite is typically found with grossular in......
-
Demaratus (king of Sparta)
king of Sparta, together with Cleomenes I, who frustrated Cleomenes’ designs on both Athens and Aegina. He was consequently dethroned by Cleomenes on a false charge of illegitimacy, upon which he fled to Persia and was given some small cities in northwestern Asia Minor, which his descendants held in ...
-
Demarçay, Eugène-Anatole (French chemist)
...rare-earth metal of the lanthanoid series of the periodic table; it is the least dense, softest, and most volatile member of the lanthanoid series. The element was discovered (1896) by Eugène-Anatole Demarçay and named for Europe. One of the least abundant rare earths, it occurs in minute amounts in many rare-earth minerals such as monazite and also in the products of......
-
Demarest, David (French Huguenot)
...north of Hackensack on the east bank of the Hackensack River. Early Dutch settlers established a plantation-type farm called Vriesendael, which was pillaged by Delaware Indians in 1643. In 1675 David Demarest (or des Marest), a French Huguenot, and his sons received a land grant, which included the former farm area. Two years later they established the first permanent settlement. Their......
-
Demaret, Jimmy (American golfer)
...north of Hackensack on the east bank of the Hackensack River. Early Dutch settlers established a plantation-type farm called Vriesendael, which was pillaged by Delaware Indians in 1643. In 1675 David Demarest (or des Marest), a French Huguenot, and his sons received a land grant, which included the former farm area. Two years later they established the first permanent settlement. Their.........
-
Demavend, Mount (mountain, Iran)
extinct volcanic peak of the Elburz Mountains, about 42 miles (68 km) northeast of Tehrān, in northern Iran. Estimates of its height vary from about 18,400 feet (5,600 metres) to more than 19,000 feet (5,800 metres), and it dominates the surrounding ranges by 3,000 to 8,000 feet (900 to 2,450 metres). Its steep, snowcapped cone is for...
-
Demba (people)
...week of the child’s life. Among the Asante of Ghana, twins are assigned a status akin to that of living shrines; a sign of abundant fertility, they are deemed repositories of sacredness. For the Ndembu of the Democratic Republic of the Congo, by contrast, twins represent an excess of fertility more characteristic of the animal world than the human, and rituals are undertaken to protect t...
-
Dembiński, Henryk (Polish soldier and revolutionary leader)
Polish soldier and revolutionary leader. Dembiński was the chief military commander in the Polish revolt of 1830–31, and he served as commander in chief of the Hungarian army during the Hungarian revolution of 1848–49....
-
Dembinszky, Henrik (Polish soldier and revolutionary leader)
Polish soldier and revolutionary leader. Dembiński was the chief military commander in the Polish revolt of 1830–31, and he served as commander in chief of the Hungarian army during the Hungarian revolution of 1848–49....
-
Dembo, Richard (French writer, director, producer, and actor)
...
-
Demchukdongrub (Mongolian leader)
At that time, refugees from Inner Mongolia swarmed into the Mongolian People’s Republic. The Japanese had organized a puppet government of Inner Mongolia under Teh Wang (Prince Teh, Demchukdongrub). He had, however, tried to minimize Japanese control and to promote Mongol nationalism. When the Chinese communists came to power in Inner Mongolia, he was condemned as a war criminal but later.....
-
deme (biogenetics)
in biogenetics, a population of organisms within which the exchange of genes is completely random; i.e., all mating combinations between individuals of opposite sexes have the same probability of occurrence. The deme usually is not a closed population but contributes individuals to neighbouring populations and receives immigrants from them....
-
deme (ancient Greek government)
in ancient Greece, country district or village, as distinct from a polis, or city-state. Dēmos also meant the common people (like the Latin plebs). In Cleisthenes’ democratic reform at Athens (508/507 bc), the demes of Attica (the area around Athens) were given sta...
-
Demelli, Francesco Ezechiele Ermenegildo, Cavaliere Suppé (Austrian composer)
Austrian composer of light operas. He greatly influenced the development of Austrian and German light music up to the middle of the 20th century....
-
dementia (pathology)
chronic, usually progressive deterioration of intellectual capacity associated with the widespread loss of nerve cells and the shrinkage of brain tissue. Dementia is most commonly seen in the elderly (senile dementia), though it is not part of the norm...
-
dementia infantilis (neurobiological disorder)
a rare neurobiological disorder characterized by the deterioration of language and social skills and by the loss of intellectual functioning following normal development throughout at least the initial two years of life. The disorder was first described in 1908 by Austrian educator Thomas Heller. However, because the disorder is rare, occurring in one in every 50,000–100,...
-
dementia paralytica (pathology)
psychosis caused by widespread destruction of brain tissue occurring in some cases of late syphilis. Mental changes include gradual deterioration of personality, impaired concentration and judgment, delusions, loss of memory, disorientation, and apathy or violent rages. Convulsions are not uncommon, and while temporary remissions sometimes ...
-
dementia praecox (psychology)
any of a group of severe mental disorders that have in common such symptoms as hallucinations, delusions, blunted emotions, disordered thinking, and a withdrawal from reality. Schizophrenics display a wide array of symptoms, but five main types of schizophrenia, differing in their specific symptomatology as follows, are reco...
-
“Dementia Praecox oder Gruppe der Schizophrenien” (work by Bleuler)
...in 1908 in a paper based on a study of 647 Burghölzli patients. He then expanded on his paper of 1908 in Dementia Praecox oder Gruppe der Schizophrenien (1911; Dementia Praecox; or, The Group of Schizophrenias). He argued in this monograph that dementia praecox was not a single disease, was not invariably incurable, and did not always progress to......
-
Dementia Praecox; or the Group of Schizophrenias (work by Bleuler)
...in 1908 in a paper based on a study of 647 Burghölzli patients. He then expanded on his paper of 1908 in Dementia Praecox oder Gruppe der Schizophrenien (1911; Dementia Praecox; or, The Group of Schizophrenias). He argued in this monograph that dementia praecox was not a single disease, was not invariably incurable, and did not always progress to......
-
dementia, senile (disease)
In these dementias there is a progressive intellectual impairment that proceeds to lethargy, inactivity, and gross physical deterioration and eventually to death within a few years. Presenile dementias are arbitrarily defined as those that begin in persons under the age of 65. In old age the most common causes of dementia are Alzheimer disease and cerebral arteriosclerosis. Dementia from......
-
Demerara (Dutch colony, Guyana)
...the Demerara River; the Dutch renamed it Stabroek and continued to develop it. The British took over in 1796 and remained in possession, except for short intervals, until 1814, when they purchased Demerara, Berbice, and Essequibo, which in 1831 were united as the colony of British Guiana....
-
Demerara River (river, Guyana)
river in eastern Guyana that rises in the forests of central Guyana and flows northward without important tributaries for 215 miles (346 km) to the Atlantic Ocean at Georgetown. Its narrow estuary and rapid flow keep clear a direct channel of 16–20 feet (5–6 m) to the ocean. Oceangoing steamers ascend 65 miles ...
-
Demerol (drug)
synthetic drug used in the treatment of moderate to severe pain. It is an opioid analgesic, and thus its effects on the body resemble those of opium or morphine, one of opium’s purified constituents. A common trade name for meperidine is Demerol....
-
Demes, The (work by Eupolis)
...and more than 460 fragments survive. Objects of his satire included the demagogues Cleon and Hyperbolus and the wealthy Callias and Alcibiades and their fashionable circle. In his last play, The Demes, written just after the disastrous Athenian expedition led by Alcibiades to Sicily (412 bc), he addressed himself with patriotic fervour to the problem of how the fortunes of ...
-
demesne (land tenure)
in English feudal law, that portion of a manor not granted to freehold tenants but either retained by the lord for his own use and occupation or occupied by his villeins or leasehold tenants. When villein tenure developed into the more secure copyhold and leaseholders became protected against premature eviction, the “lord’s demesne” came ...
-
Demeter (Greek mythology)
in Greek religion, daughter of the deities Cronus and Rhea, sister and consort of Zeus (the king of the gods), and goddess of agriculture. Her name indicates that she is a mother....
-
Demeter and Other Poems (poetry by Tennyson)
In 1889 Tennyson wrote the famous short poem “Crossing the Bar,” during the crossing to the Isle of Wight. In the same year he published Demeter and Other Poems, which contains the charming retrospective “To Mary Boyle,” “The Progress of Spring,” a fine lyric written much earlier and rediscovered, and “Merlin and the Gleam,” an allegor...
-
Demeter of Cnidus (Greek sculpture)
...passionless features of Classical sculpture into studies of intense emotion. Praxiteles and Scopas seem to typify the new spirit that can readily be discerned in surviving original sculptures. The “Demeter of Cnidus” (British Museum, London; perhaps by the Athenian sculptor Leochares) is Classical in mood, but the features are....
Have a comment about this page?
Please, contact us. If this is a correction, your suggested change will be reviewed by our editorial staff.