• El Salvador, República de

    El Salvador, country of Central America. El Salvador is the smallest and most densely populated of the seven Central American countries. Despite having little level land, it traditionally was an agricultural country, heavily dependent upon coffee exports. By the end of the 20th century, however,

  • El Salvador, University of (university, San Salvador, El Salvador)

    San Salvador: The National University of El Salvador was founded there in 1841 as Colegio de la Asunción. San Salvador is also the seat of the Central American University of José Simeón Cañas (1965). During the late 1970s the city became the focus of violence between the government…

  • El Seíbo (Dominican Republic)

    El Seíbo, city, eastern Dominican Republic, on the Soco River. Founded in 1502, the city serves as a trading centre for the agricultural hinterland. The region yields cacao, coffee, sugarcane, and corn (maize), in addition to beeswax and medicinal plants. Cattle are also raised. The city lies on

  • El Tajín (archaeological site, Mexico)

    Native American art: Mexico and Middle America: …up a major centre at El Tajín, remained limited to their own group. Other pre-Totonac folk who were active in Veracruz produced innumerable “smiling face” figurines and related works that give an impression of an exuberant, happy people. Remarkable among these clayworks are the small clay whistles that abound in…

  • El Teniente (Chile)

    El Teniente, mining settlement, O’Higgins región, central Chile. The site of the world’s largest underground copper mine, it lies in the Andes Mountains about 60 miles (100 km) southeast of Santiago. It accounts for much of Chile’s annual copper production. Copper is smelted at El Teniente,

  • El Tigre (Venezuela)

    El Tigre, city, central Anzoátegui estado (state), northeastern Venezuela. It is situated in the highlands east of the Barcelona gap. The city is a commercial centre in the Oficina oil fields. Oil is piped 100 miles (160 km) north-northeastward to Puerto La Cruz, which produces some of Venezuela’s

  • El Tor (bacterium biotype)

    cholera: The cholera bacterium and toxin: …into two biotypes: classical and El Tor. These two biotypes each contain two serotypes, called Inaba and Ogawa (some classifications recognize a third serotype, Hikojima), which are differentiated based on their biochemical properties, namely their expression of type-specific antigens. Inaba and Ogawa serotypes both express a common cholera antigen known…

  • El trueno entre las hojas (book by Rao Bastos)

    Augusto Roa Bastos: …first collection of short stories, El trueno entre las hojas (1953; “Thunder Among the Leaves”), which he also adapted as a film script, describes the Paraguayan experience with emphasis on violence and social injustice. Roa Bastos began to experiment with magic realism, in which realistic descriptions are enhanced by myths…

  • El Yopal (Colombia)

    Yopal, town and capital of Casanare departamento, eastern Colombia. The original settlement (caserío) of Yopal was founded in 1935 by Pedro Pablo González, and it has been the seat of Casanare intendency (now departamento) since the creation of Casanare in 1974. Located at the western edge of the

  • El Zanjón, peace of (Spain [1878])

    Spain: The restored monarchy, 1875–1923: …accepted the peace settlement of El Zanjón (1878), the restored monarchy provided the most stable government Spain had known since 1833. This stability was sustained by an uneven but respectable economic growth.

  • El ʿAl Netive Awir Le-Yisraʾel

    El Al Israel Airlines, Israeli airline founded by Israel in November 1948 after the establishment of the new nation. It flew its first commercial scheduled flights—to Rome and Paris—in July 1949, and by the 1980s it was flying routes from Jerusalem and Tel Aviv to many of the major cities of

  • EL-1 (nuclear reactor)

    Frédéric and Irène Joliot-Curie: 15, 1948, of ZOE (zéro, oxyde d’uranium, eau lourde), the first French nuclear reactor, which, though only moderately powerful, marked the end of the Anglo-Saxon monopoly. In April 1950, however, during the climax of the cold war and anticommunism, Prime Minister Georges Bidault removed him without explanation from…

  • El-al ben Shachar (Jewish physician and scholar)

    Hillel ben Samuel was a physician, Talmudic scholar, and philosopher who defended the ideas of the 12th-century Jewish philosopher Maimonides during the “years of controversy” (1289–90), when Maimonides’ work was challenged and attacked; Hillel ben Samuel denounced in turn the adherents of the

  • El-Djelfa (Algeria)

    Djelfa, town, north-central Algeria, in the Oulad Naïl Mountains at an elevation of 3,734 feet (1,138 metres). It is situated between the towns of Bou Saâda and Laghouat. Djelfa town is at a point of transition between the dry, steppelike High Plateaus of the north, with their chotts (intermittent

  • El-Djouf (desert region, western Africa)

    El-Djouf, desert region in western Africa, at the western edge of the Sahara. It occupies the border region of eastern Mauritania and western

  • El-Ferdan Bridge (bridge, Suez Canal, Egypt)

    El-Ferdan Bridge, longest rotating metal bridge in the world, spanning the western shipping lane of the Suez Canal in northeastern Egypt, from the lower Nile River valley near Ismailia to the Sinai Peninsula. Opened on November 14, 2001, the bridge has a single railway track running down the middle

  • El-Giza (Egypt)

    Giza, city, capital of Al-Jīzah muḥāfaẓah (governorate) in Upper Egypt, located on the west bank of the Nile River just south-southwest of Cairo. It is a suburb of the national capital, with a distinctive character enriched by several archaeological and cultural sites. The district was settled in

  • El-Hamra Plateau (plateau, Libya)

    Al-Ḥamrāʾ Plateau, desolate rocky plateau of the Sahara, northwestern Libya. Located mostly in Tripolitania, it occupies an area measuring about 275 miles (440 km) by 190 miles (305 km). Its bare rock outcrops reach a height of about 2,700 feet (825 metres). Wells are drilled for petroleum, which

  • El-Khazzani, Ayoub (Moroccan militant)

    Paris attacks of 2015: Prelude to the attacks: Ayoub El-Khazzani, a militant with ties to ISIL, smuggled an AK-47, a semiautomatic pistol, and hundreds of rounds of ammunition onto the crowded Paris-bound train. A potential massacre was averted when El-Khazzani was subdued by passengers, among them a pair of off-duty U.S. military personnel…

  • ELA-STV (labor organization, Spain)

    Spain: Labour and taxation: …Sindical Independiente de Funcionarios); the Basque Workers’ Solidarity (Euzko Langilleen Alkartasuna–Solidaridad de Trabajadores Vascos; ELA-STV), which is independent but has ties to the Basque Nationalist Party; and the General Confederation of Labour (Confederación General del Trabajo; CGT), the tiny remnant of the once-powerful anarcho-syndicalist union organization. Overall, with about one-sixth…

  • elaboration-likelihood model (psychology)

    persuasion: …the conflict-resolution model is the elaboration-likelihood model (ELM) of persuasion, put forth in 1980 by American psychologists John Cacioppo and Richard Petty. The ELM emphasizes the cognitive processing with which people react to persuasive communications. According to this model, if people react to a persuasive communication by reflecting on the…

  • elachista (matter)

    atomism: The elachista of the early Aristotelian commentators: …systems the atoms were called elachista (“very small” or “smallest”). The choice of this term was connected with the Aristotelian rejection of the infinite divisibility of matter. Each substance had its own minimum of magnitude below which it could not exist. If such a minimum particle were to be divided,…

  • Elaeagnaceae (plant family)

    Elaeagnaceae, the oleaster family of flowering plants (order Rosales), comprising 45–60 species in 3 genera. The oleaster family is largely composed of shrubs and small trees of the Northern Hemisphere, especially in steppe and coastal regions. The plants have a characteristic silvery or

  • Elaeagnus angustifolia (tree)

    oleaster, 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 that are silvery on the undersides from a covering of minute scales. The flowers are small, greenish, fragrant, and

  • Elaeis (plant genus)

    palm: Distribution: …Chamaerops in Europe and Africa, Elaeis (oil palm) and Raphia (raffia palm, or jupati) in Africa and America, and Borassus (palmyra palm), Calamus (rattan palm), Hyphaene (doum palm), and Phoenix (date palm) in Africa and Asia. Numbers of individuals of a species may be few or many.

  • Elaeis guineensis (tree)

    oil palm, (Elaeis guineensis), African tree in the palm family (Arecaceae), cultivated as a source of oil. The oil palm is grown extensively in its native West and Central Africa, as well as in Malaysia and Indonesia. Palm oil, obtained from the fruits, is used in making soaps, cosmetics, candles,

  • Elaeis melanococca (tree)

    oil palm: The American oil palm (Elaeis oleifera) is native to Central and South America and is sometimes cultivated under the erroneous name Elaeis melanococca. Unlike the African oil palm, the trunk of the American oil palm creeps along the ground and bears flat leaves. Both the American…

  • Elaeis oleifera (tree)

    oil palm: The American oil palm (Elaeis oleifera) is native to Central and South America and is sometimes cultivated under the erroneous name Elaeis melanococca. Unlike the African oil palm, the trunk of the American oil palm creeps along the ground and bears flat leaves. Both the American…

  • elaenia (bird)

    elaenia, (genus Elaenia), any of about 20 species of plain-coloured New World flycatchers, family Tyrannidae (order Passeriformes), with a short bill and modest, ragged crest, usually concealing a white or yellow crown patch. Found in Central America, South America, and the West Indies, most

  • Elagabalus (Roman emperor)

    Elagabalus was a Roman emperor from 218 to 222, notable chiefly for his eccentric behaviour. The family of his mother, Julia Soaemias, were hereditary high priests of the god Baal at Emesa (in ancient Syria), worshiped in that locality under the name Elah-Gabal (thus Elagabalus). The emperor

  • Elagatis bipinnulata (fish)

    runner: The rainbow runner (Elagatis bipinnulata) is a spectacularly coloured fish, metallic blue on the upper half of the body and yellow on the lower. Two deeper blue longitudinal lines complement the brilliant colour pattern. Rainbow runners attain lengths of more than 1.2 m (4 feet).

  • Elāhī-nāma (work by ʿAṭṭār)

    Farīd al-Dīn ʿAṭṭār: …this prolific poet include the Elāhī-nāma (The Ilahī-nāma or Book of God) and the Moṣībat-nāma (“Book of Affliction”), both of which are mystical allegories similar in structure and form to Manṭeq al-ṭayr; the Dīvān (“Collected Poems”); and the famous prose work Tadhkerat al-Awlīyāʾ, an invaluable source of information on the…

  • Elaine (British legendary figure)

    Elaine, character of Arthurian legend, first portrayed in Le Morte Darthur (1485) by Sir Thomas Malory. In Malory’s sprawling work, Elaine (or Elayne) is the name of five women with overlapping identities. The best known and most cited of these is Elaine Le Blank, known as the Fair Maid of Astolat,

  • elaiosome (plant anatomy)

    bloodroot: …feature fleshy structures known as elaiosomes to attract ants for dispersal.

  • Elais (Greek mythology)

    Anius: three daughters, Oeno, Spermo, and Elais—that is, Wine, Grain Seed, and Oil—were granted by Dionysus the gift of bringing these three crops to fruition. In Ovid’s Metamorphoses the Greek army tries to force Anius’s daughters to come to Troy, whereupon Dionysus turns them into doves, the sacred birds of Delos.…

  • Elam (ancient kingdom, Iran)

    Elam, ancient country in southwestern Iran approximately equivalent to the modern region of Khūzestān. Four prominent geographic names within Elam are mentioned in ancient sources: Awan, Anshan, Simash, and Susa. Susa was Elam’s capital, and in classical sources the name of the country is sometimes

  • Elämä ja aurinko (novel by Sillanpää)

    Frans Eemil Sillanpää: Sillanpää’s first novel, Elämä ja aurinko (1916; “Life and the Sun”), the story of a young man who returns home in midsummer and falls in love, is characteristic. People are seen as essentially part of nature. Instinct, through which life’s hidden purpose is revealed, rules human actions.

  • Elamite (people)

    Babylon: History: …city was sacked by the Elamites. Babylon’s acknowledged political supremacy is shown by the fact that the dynasty of Nebuchadrezzar I (1124–03), which endured for more than a century, made the city its capital, though the dynasty did not originate there.

  • Elamite language

    Elamite language, extinct language spoken by the Elamites in the ancient country of Elam, which included the region from the Mesopotamian plain to the Iranian Plateau. Elamite documents from three historical periods have been found. The earliest Elamite writings are in a figurative or pictographic

  • Elamtu (ancient kingdom, Iran)

    Elam, ancient country in southwestern Iran approximately equivalent to the modern region of Khūzestān. Four prominent geographic names within Elam are mentioned in ancient sources: Awan, Anshan, Simash, and Susa. Susa was Elam’s capital, and in classical sources the name of the country is sometimes

  • Elan Vital (religious organization)

    Elan Vital, international religious organization that teaches spiritual enlightenment through the practice of yoga and chanting. Although beset by court battles and schism, it remains active in the United States and many other countries. Elan Vital is the successor organization of the Divine Light

  • élan vital (philosophy)

    Henri Bergson: Philosophical triumphs: …as the endurance of an élan vital (“vital impulse”) that is continually developing and generating new forms. Evolution, in short, is creative, not mechanistic. (See creative evolution.)

  • Élan, L’  (French art review)

    Amédée Ozenfant: … and Guillaume Apollinaire, the review L’Élan, which aimed to maintain communication between avant-garde artists serving in the war and those who remained in Paris. The review published essays discussing the principles of Cubism, notably Ozenfant’s “Notes on Cubism” (1916), which appeared in the final issue.

  • Elancon (India)

    Kollam, port city, southern Kerala state, southwestern India. It lies on the Malabar Coast of the Arabian Sea northwest of Thiruvananthapuram, the state capital. The city is situated next to Asthamudi Lake, an inlet of the sea, and is linked with Alappuzha and Kochi (Cochin) to the north by a

  • eland (mammal)

    eland, (genus Taurotragus), either of two very large, oxlike African antelopes of the spiral-horned antelope tribe (Tragelaphini, family Bovidae), which also includes the bushbuck and the kudus. The giant, or Derby, eland (Taurotragus derbianus) inhabits woodlands filled with the broad-leaved doka

  • Elandsfontein (archaeological site, Cape of Good Hope, South Africa)

    Hopefield: The archaeological site of Elandsfontein is located 8 miles (13 km) southwest of Hopefield, about 10 miles (16 km) inland from an estuary of Saldanha Bay and 330 feet (100 m) above sea level. In the early 1950s a large collection of fossilized bones and Paleolithic artifacts was discovered…

  • Elanoides forficatus (bird, Elanoides forficatus)

    kite: The swallow-tailed kite of the New World (Elanoides forficatus) is a striking black and white bird of the subfamily Perninae. It is about 60 cm long, including its long forked tail. It is most common in tropical eastern South America but also occurs from Central America…

  • Elanus leucurus (bird)

    kite: The white-tailed kite (Elanus leucurus; subfamily Elaninae) occurs from Argentina to California, where it is one of the few North American raptors increasing in number. It is gray with a white tail, head, and underparts and conspicuous black shoulder patches. It eats rodents. Similar kites of…

  • Elaphe (reptile)

    rat snake, any of between 40 and 55 species of the genus Elaphe, of the family Colubridae and similar forms. They occur in North America, Europe, and Asia east to the Philippines. Most are found in woodlands and around farm buildings. They hunt rats and mice and kill them by constriction. They also

  • Elaphe guttata (reptile)

    rat snake: The corn snake (E. guttata) ranges from New Jersey and Florida to Utah and northeastern Mexico. In the east it is yellow or gray, with black-edged red blotches, and is often referred to as the red rat snake. In the west it usually is pale gray,…

  • Elaphe longissima (reptile)

    rat snake: The Aesculapian snake (E. longissima), plain and dark coloured, is native to southeastern Europe and Asia Minor. In ancient times it was sacred to Aesclepius, god of medicine; the present isolated populations in Germany and Switzerland are descended from specimens conveyed to health resorts there by…

  • Elaphe obsoleta obsoleta (reptile)

    rat snake: The black rat snake, or pilot black snake (Elaphe obsoleta obsoleta), of the eastern United States usually is about 1.2 m (about 4 feet) long but may exceed 2.5 m (8 feet). It is black, with whitish chin and throat—like the true black snake (see racer)—but…

  • Elaphe quatuorlineata (reptile)

    rat snake: …Europe’s largest serpents is the four-lined snake (E. quatuorlineata), which may be 1.8 m (about 6 feet) long. It ranges from Italy to the Caucasus and Turkey and is grayish, with two dorsal and two lateral stripes. The Aesculapian snake (E. longissima), plain and dark coloured, is native to southeastern…

  • Elaphe radiata (reptile)

    copperhead: …India is a rat snake, Elaphe radiata.

  • Elaphe vulpina (reptile)

    rat snake: The fox snake (E. vulpina), chiefly of farmlands of Wisconsin to Missouri, is yellowish or pale brown above, with strong dark blotches, and yellow below, with black checkering. Its head may be quite reddish.

  • Elaphoglossum (fern genus)

    fern: Annotated classification: …fern, about 250 species), and Elaphoglossum (tongue fern, 600–700 species), distributed nearly worldwide. Family Hypodematiaceae Small family of 2 genera, Hypodematium (about 20 species) and Leucostegia (2 species). Family Lomariopsidaceae Plants in soil, on

  • Elaphurus davidianus (mammal)

    Père David’s deer, (Elaphurus davidianus), large, rare Asian deer in the family Cervidae (order Artiodactyla). The only member of its genus, it is unknown in nature within historical times. Presumably native to northern China, it is now found only in zoos, private animal collections, and game

  • elapid (snake)

    elapid, any of about 300 venomous species of the snake family Elapidae, characterized by short fangs fixed in the front of the upper jaw. Terrestrial elapids generally resemble the more abundant colubrids, whereas aquatic elapids may possess paddle-shaped tails and other structures adapted to

  • Elapidae (snake)

    elapid, any of about 300 venomous species of the snake family Elapidae, characterized by short fangs fixed in the front of the upper jaw. Terrestrial elapids generally resemble the more abundant colubrids, whereas aquatic elapids may possess paddle-shaped tails and other structures adapted to

  • Elara (astronomy)

    Jupiter: Other satellites: Himalia, Lysithea, and Elara—has prograde orbits. (In the case of these moons, retrograde motion is in the direction opposite to Jupiter’s spin and motion around the Sun, which are counterclockwise as viewed from above Jupiter’s north pole, whereas prograde, or direct, motion is in the same direction.) In…

  • ELAS (political organization, Greece)

    EAM-ELAS, communist-sponsored resistance organization (formed September 1941) and its military wing (formed December 1942), which operated in occupied Greece during World War II. Fighting against the Germans and the Italians as well as against other guerrilla bands, particularly EDES, EAM-ELAS

  • elasmobranch (fish subclass)

    chondrichthyan: Problems of taxonomy: …further grouped into one subclass, Elasmobranchii, and the chimaeras into another, Holocephali. Some authorities classify the elasmobranchs into one class (Selachii) and classify the chimaeras into another (Holocephali); however, assigning the two groups class rank implies a degree of distinctness equal to that of the amphibians (Amphibia), reptiles (Reptilia), birds…

  • Elasmobranchii (fish subclass)

    chondrichthyan: Problems of taxonomy: …further grouped into one subclass, Elasmobranchii, and the chimaeras into another, Holocephali. Some authorities classify the elasmobranchs into one class (Selachii) and classify the chimaeras into another (Holocephali); however, assigning the two groups class rank implies a degree of distinctness equal to that of the amphibians (Amphibia), reptiles (Reptilia), birds…

  • Elasmosaurus (fossil marine reptile)

    plesiosaur: For example, Elasmosaurus, a plesiosaurid, had as many as 76 vertebrae in its neck alone and reached a length of about 13 metres (43 feet), fully half of which consisted of the head and neck. In contrast, Kronosaurus, an early Cretaceous pliosaur whose fossils have been unearthed…

  • Elassomatidae

    perciform: Annotated classification: Family Elassomatidae (pygmy sunfishes) Once classified in the Centrarchidae; recent studies shed doubt on the close relationships of pygmy sunfishes to that family. Freshwater, eastern United States. 1 genus, Elassoma, with 6 species. Suborder Labroidei 6 families, about 2,274 species. Family Cichlidae (

  • elastase (enzyme)

    connective tissue: Extracellular fibres: …however, by a specific enzyme, elastase, present in the pancreas. Upon chemical analysis, elastin, like collagen, is found to be rich in glycine and proline, but it differs in its high content of valine and in the presence of an unusual amino acid, desmosine. As their name implies, elastic fibres…

  • elastic cartilage (anatomy)

    cartilage: Elastic cartilage, which is yellow in appearance, is more pliable than the other two forms because it contains elastic fibres in addition to collagen. In humans it makes up the external ear, the auditory tube of the middle ear, and the epiglottis.

  • elastic collision (physics)

    mechanics: Collisions: …collision is said to be elastic.

  • elastic constant (mechanics)

    mechanics of solids: The general theory of elasticity: …maximum possible number of independent elastic moduli in the most general anisotropic solid were settled by the British mathematician George Green in 1837. Green pointed out that the existence of an elastic strain energy required that of the 36 elastic constants relating the 6 stress components to the 6 strains,…

  • elastic defense (warfare)

    World War I: The Western Front, March–September 1918: …was frustrated by the “elastic defense” that Pétain had recently been prescribing but that the local commanders had failed to practice against the offensive of May 27. A drive from Dormans, on the left flank of the Germans’ huge Soissons–Reims bulge, across the Marne toward Épernay simply made the…

  • elastic deformation (mechanics)

    deformation and flow: Most solids initially deform elastically; that is to say, they return to their original shape when the load is removed. Rigid materials such as metals, concrete, or rocks sustain large forces while undergoing little deformation, but if sufficiently large forces are applied, the materials can no longer sustain them…

  • elastic fibre (anatomy)

    elastic fibre, any of the yellowish branching fibres composed primarily of the protein elastin, frequently arranged in plates or perforated membranes, as in the walls of the large arteries. Unlike collagenous fibres, they show no orderly fibrous subunits under microscopic examination but sometimes

  • elastic limit (mechanics)

    elastic limit, maximum stress or force per unit area within a solid material that can arise before the onset of permanent deformation. When stresses up to the elastic limit are removed, the material resumes its original size and shape. Stresses beyond the elastic limit cause a material to yield or

  • elastic modulus (mechanics)

    mechanics of solids: The general theory of elasticity: …maximum possible number of independent elastic moduli in the most general anisotropic solid were settled by the British mathematician George Green in 1837. Green pointed out that the existence of an elastic strain energy required that of the 36 elastic constants relating the 6 stress components to the 6 strains,…

  • elastic rebound (physics)

    uplift: Such elastic reboundis both measurable and ongoing in southern Canada and in the general Scandinavian area today.

  • elastic rebound theory (geology)

    Harry Fielding Reid: …who in 1911 developed the elastic rebound theory of earthquake mechanics, still accepted today.

  • elastic recovery (physics)

    uplift: Such elastic reboundis both measurable and ongoing in southern Canada and in the general Scandinavian area today.

  • elastic resistance training (exercise)

    resistance training: Elastic resistance: …and springs are forms of elastic resistance. The premise of using elastic resistance is that the greater the stretch of the band or spring, the greater the force needed to overcome the resistance. If the density is too great, the muscle will not be able to complete the full range…

  • elastic scattering (physics)

    radiation measurement: Slow neutrons: Slow neutrons frequently undergo elastic scattering interactions with nuclei and may in the process transfer a fraction of their energy to the interacting nucleus. Because the kinetic energy of a neutron is so low, however, the resulting recoil nucleus does not have enough energy to be classified as an…

  • elastic skeleton (anatomy)

    animal: Types of skeletons and their distribution: Elastic skeletons do not change shape but simply bend when a muscle contracts. Muscle relaxation results either from a muscle contracting in the opposite direction to its antagonist or from the skeleton resuming its original position. The tentacles of many hydrozoan coelenterates, the mesoglea of…

  • elastic strain (mechanics)

    earthquake: Natural forces: …energy can be released by elastic strain, gravity, chemical reactions, or even the motion of massive bodies. Of all these the release of elastic strain is the most important cause, because this form of energy is the only kind that can be stored in sufficient quantity in the Earth to…

  • elastic wave (physics)

    elastic wave, motion in a medium in which, when particles are displaced, a force proportional to the displacement acts on the particles to restore them to their original position. If a material has the property of elasticity and the particles in a certain region are set in vibratory motion, an

  • elasticity (mineralogy)

    rare-earth element: Elastic properties: As with most of the other properties of the rare-earth metals, the elastic moduli of the rare-earth metals fall in the middle percentile of the other metallic elements. The values for scandium and yttrium are about the same as those of the end…

  • elasticity (physics)

    elasticity, ability of a deformed material body to return to its original shape and size when the forces causing the deformation are removed. A body with this ability is said to behave (or respond) elastically. To a greater or lesser extent, most solid materials exhibit elastic behaviour, but there

  • elasticity (economics)

    elasticity, in economics, a measure of the responsiveness of one economic variable to another. A variable y (e.g., the demand for a particular good) is elastic with respect to another variable x (e.g., the price of the good) if y is very responsive to changes in x; in contrast, y is inelastic with

  • elasticity, modulus of (mechanics)

    mechanics of solids: The general theory of elasticity: …maximum possible number of independent elastic moduli in the most general anisotropic solid were settled by the British mathematician George Green in 1837. Green pointed out that the existence of an elastic strain energy required that of the 36 elastic constants relating the 6 stress components to the 6 strains,…

  • elasticoviscous deformation (mechanics)

    rock: Stress-strain relationships: In elasticoviscous deformation, there is combined elastic and viscous behaviour. The material yields continuously (viscously) for a constant applied load. An example of such behaviour is creep, a slow, permanent, and continuous deformation occurring under constant load over a long time in such materials as crystals,…

  • Elasticum (work by Hausmann)

    Raoul Hausmann: …was Hausmann’s photomontage and collage Elasticum (1920), which includes images of tires, a speedometer, nuts and bolts, and, most likely, the head of Henry Ford—inventor of the assembly line and father of mass-produced automobiles. Throughout the Dada era, which flourished for about six years (1916–22), Hausmann contributed his “Dadasophy” (his…

  • elastin (biology)

    aging: Changes in structural tissues: Elastin is the molecule responsible for the elasticity of blood vessel walls. With age, progressive loss of elasticity of vessels occurs, presumably because of fragmentation of the elastin molecule.

  • elastomer (chemical compound)

    elastomer, any rubbery material composed of long chainlike molecules, or polymers, that are capable of recovering their original shape after being stretched to great extents—hence the name elastomer, from “elastic polymer.” Under normal conditions the long molecules making up an elastomeric

  • Elat (Israel)

    Elat, port city, southern extremity of Israel. It lies at the south tip of the Negev and at the head of the Gulf of Aqaba (Hebrew, Mifratz Elat), the eastern arm of the Red Sea. Al-ʿAqabah, Jordan, also located on the Gulf of Aqaba, lies 4 miles (7 km) to the southeast. Modern Elat is situated just

  • Elat (Semitic goddess)

    Asherah, ancient West Semitic goddess, consort of the supreme god. Her principal epithet was probably “She Who Walks on the Sea.” She was occasionally called Elath (Elat), “the Goddess,” and may have also been called Qudshu, “Holiness.” According to texts from Ugarit (modern Ras Shamra, Syria),

  • elater (plant anatomy)

    bryophyte: Form and function: …within it elongate cells (elaters) with coiled thickenings that are scattered among the spores. When the sporangium opens, usually very rapidly when dry, it does so along four longitudinal lines, exposing the elaters, which uncoil rapidly and throw themselves and the adjacent spores into the air. Other devices exist…

  • Elateridae (insect family)

    click beetle, (family Elateridae), family of approximately 7,000 species of beetles named for the clicking noise made when seized by a predator. Taxonomy See also list of insects. Most click beetles range between 2.5 and 18 mm (less than 0.75 inch) in length and are brown or black in color with

  • elateriform larva (zoology)

    insect: Types of larvae: …campodeiform (elongated, flattened, and active), elateriform (wireworm-like), and vermiform (maggot-like). The three types of pupae are: obtect, with appendages more or less glued to the body; exarate, with the appendages free and not glued to the body; and coarctate, which is essentially exarate but remaining covered by the cast skins…

  • Elateroidea (insect superfamily)

    coleopteran: Annotated classification: Superfamily Elateroidea Forecoxae small; metasternum without transverse suture; larvae with no free labrum. Select families below. Family Brachypsectridae A few species in Asia and California. Family Cantharidae (soldier beetles)

  • Elath (Semitic goddess)

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