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Lukas, Paul (Hungarian-American actor)
American journalist and author (b. April 25, 1933, New York, N.Y.--d. June 5, 1997, New York), wrote meticulous examinations of the societal and racial fissures in the U.S. He was known and highly regarded for his tenacity, perfectionism, and painstaking research and won a number of the country’s top literature and journalism awards, including two Pulitzer Prizes. Lukas was educated at ......
Lukasbund (German art society)
one of an association formed by a number of young German painters in 1809 to return to the medieval spirit in art. Reacting particularly against 18th-century Neoclassicism, the brotherhood was the first effective antiacademic movement in European painting. The Nazarenes believed that all art should serve a moral or religious purpose; they admired painters of the late Middle Ages and early Renaissa...
Lukashenka, Alyaksandr (president of Belarus)
Belarusian politician who espoused communist principles and who became president of the country in 1994....
Lukashenka, Alyaksandr Hrygorevich (president of Belarus)
Belarusian politician who espoused communist principles and who became president of the country in 1994....
Lukashenko, Alyaksandr (president of Belarus)
Belarusian politician who espoused communist principles and who became president of the country in 1994....
Łukasiewicz, Jan (Polish philosopher)
...from his dissertation to the appearance in 1916 of his first work on the theory of collective sets. Leśniewski attributed the discovery of his true intellectual vocation to the influence of Jan Łukasiewicz, also a pupil of Twardowski and then a privat dozent at the University of Lwów. Already learned in the history of logic, to which he was to make outstanding......
Łukasiński, Walerian (Polish rebel)
Out of Freemasonry, which the tsar at first patronized, there grew a secret Polish Patriotic Society whose aims could hardly be qualified as treason. Nevertheless, its leader, Major Walerian Łukasiński, became a national martyr when he was thrown into prison, where he languished half-forgotten for more than 40 years until his death. Other conspiracies of more radical character......
Lukasz, Paul (Hungarian-American actor)
Out of Freemasonry, which the tsar at first patronized, there grew a secret Polish Patriotic Society whose aims could hardly be qualified as treason. Nevertheless, its leader, Major Walerian Łukasiński, became a national martyr when he was thrown into prison, where he languished half-forgotten for more than 40 years until his death. Other conspiracies of more radical character.........
Luke, Gospel According to (biblical literature)
third of the four New Testament Gospels (narratives recounting the life and death of Jesus Christ), and, with Mark and Matthew, one of the three Synoptic Gospels (i.e., those presenting a common view). It is traditionally credited to Lu...
Luke, Saint (biblical author)
in Christian tradition, the author of the third Gospel and the Acts of the Apostles, a companion of the Apostle Paul, and the most literary of the New Testament writers. Information about his life is scanty. His writing style indicates a cultivated literary background. Tradition based on Gospel references has regarded him as a physician and a Gentile. He was a coworker of Paul and probably accompa...
Luke, Sir Samuel (English military officer)
...King’s school, Worcester. He afterward obtained employment in the household of the Countess of Kent, at Wrest, Bedfordshire, where he had access to a fine library. He then passed into the service of Sir Samuel Luke, a rigid Presbyterian, a colonel in the Parliamentary army, and scoutmaster general for Bedfordshire. In his service Butler undoubtedly had firsthand opportunity to study some...
Luke Skywalker (fictional character)
...intriguing twist offered in The Empire Strikes Back (1980; Star Wars: Episode V—The Empire Strikes Back), Vader is revealed to be the father of the young rebel Luke Skywalker, and at the climax of the next film, Return of the Jedi (1983; Star Wars: Episode VI—Return of the Jedi), Vader turns against the Empire to save...
Lukens, Mount (mountain, Los Angeles, California, United States)
...and tortuously shaped city of Los Angeles occupies a sizable portion of the southern part of the county. It too has a varied topography, climbing from sea level at the beach community of Venice to Mount Lukens, which rises above 5,100 feet (1,550 metres). The city started in 1781 as a tiny village of 28 square miles (73 square km) but expanded greatly through a series of annexations when it......
Lukin, Lionel (British engineer)
pioneer in the construction of the modern “unsinkable” lifeboat....
Lukins, Sheila Gail Block (American cookbook author, gourmet, and entrepreneur)
Nov. 18, 1942Philadelphia, Pa.Aug. 30, 2009New York, N.Y.American cookbook author, gourmet, and entrepreneurwho served as the food editor (1986–2009) of Parade magazine and wrote four best-selling cookbooks. With the advent of her innovative ...
Luks, George (American artist)
one of a group of American painters popularly known as the Ashcan school because of their realistic treatment of urban scenes....
Luks, George Benjamin (American artist)
one of a group of American painters popularly known as the Ashcan school because of their realistic treatment of urban scenes....
Luksic Abaroa, Andrónico (Chilean business magnate)
Chilean business magnate (b. Nov. 5, 1926, Antofagasta, Chile—d. Aug. 18, 2005, Santiago, Chile), amassed a fortune after building one of the largest business empires in Latin America. Luksic’s first investment was a copper mine in Antofagasta, which he sold to a Japanese concern in 1954. He invested the proceeds in other businesses that came to include banking and telecommunications...
Lukuas-Andreas (Cyrenian king-messiah)
...against Trajan—involving the Jews of Egypt, Cyrenaica, Cyprus, and Mesopotamia (though only to a minor degree those of Palestine)—was a widespread revolt under a Cyrenian king-messiah, Lukuas-Andreas, aimed at freeing Palestine from Roman rule. In 132–135 the same spirit of freedom inspired another uprising, the Second Jewish Revolt, led by Bar Kokhba, who may have had the....
Lukuga (Democratic Republic of the Congo)
town, southeastern Democratic Republic of the Congo, central Africa. It is a port on the west bank of Lake Tanganyika where the Lukuga River exits, and it has an airport and rail links to Lubumbashi and Kananga. In 1915 Kalemi, then the site of a British-Belgian ...
Lukuga River (river, Democratic Republic of the Congo)
tributary of the Lualaba River in eastern Congo (Kinshasa). It issues from the western shore of Lake Tanganyika at Kalemie, Congo, and flows 200 miles (320 km) west to the Lualaba River 25 miles (40 km) north of Kabalo. There are low-grade coal deposits along its tributaries, north of Kalemie and Moluba (f...
Lukyanenko, Levko (Ukrainian statesman)
...the restoration of Ukraine’s sovereignty as the main guarantee of its population’s national and human rights and the transformation of the U.S.S.R. into a genuine confederation of states. Headed by Levko Lukyanenko, with Vyacheslav Chornovil as an important leader, the Ukrainian Helsinki Union had branches in all regions of Ukraine by 1989....
Lukyanov, Anatoly (Soviet political leader)
...while they redistributed power among themselves. The choice was between genuine or controlled democracy. In early 1988 Fyodor Burlatsky was a member of a small group under the chairmanship of Anatoly Lukyanov. The latter proposed a two-stage approach to the election of a Supreme Soviet. Legal authority was to be vested in local soviets, but the relationship between the party and the......
Lula (president of Brazil)
Brazilian politician who served as president of Brazil from 2003 to 2011....
Lula da Silva, Luiz Inácio (president of Brazil)
Brazilian politician who served as president of Brazil from 2003 to 2011....
Lulach (king of Scotland)
Macbeth was buried on the island of Iona, regarded as the resting place of lawful kings but not of usurpers. His followers installed his stepson, Lulach, as king; when Lulach was killed on March 17, 1058, Malcolm III was left supreme in Scotland....
Lule River (river, Sweden)
river in the län (county) of Norrbotten, northern Sweden. It flows southeast from the Norwegian border for 280 miles (450 km) to the Gulf of Bothnia at Luleå. Between the river’s two main headstreams, the Stora (Big) Lule and the Lilla (Little) Lule, is Mount ...
Lule, Yusufu (president of Uganda)
...With these troops closing in, Amin escaped the capital. A coalition government of former exiles, calling itself the Uganda National Liberation Front (UNLF), with a former leading figure in the DP, Yusufu Lule, as president, took office in April 1979. Because of disagreement over economic strategy and the fear that Lule was promoting the interests of his own Ganda people, he was replaced in......
Luleå (Sweden)
city and seaport, seat of Norrbotten län (county), northern Sweden. The city lies at the mouth of the Lule River, where it enters the Gulf of Bothnia. Gustavus II Adolphus founded the town in 1621, 7 m...
Luleälv (river, Sweden)
river in the län (county) of Norrbotten, northern Sweden. It flows southeast from the Norwegian border for 280 miles (450 km) to the Gulf of Bothnia at Luleå. Between the river’s two main headstreams, the Stora (Big) Lule and the Lilla (Little) Lule, is Mount ...
Luli (king of Phoenicia)
Phoenician king of the cities of Tyre and Sidon who rebelled against Assyrian rule following the death of the Assyrian king Sargon II (705). Concurrent with the insurrection of Babylon under Merodach-Baladan, Luli joined with Shabaka of Egypt and Hezekiah of Judah in a revolt against Sennacherib, Sargon...
Lüli yuanyuan (Chinese compendium)
...mathematician and the following year joined the Mengyangzhai (an imperial bureau created to synthesize Western and Chinese scientific knowledge) as one of the chief editors of Lüli yuanyuan (c. 1723; “Source of Mathematical Harmonics and Astronomy”), a compendium on music, mathematics, and astronomy. Unlike earlier such endeavours, this was.....
Lüliang Mountains (mountains, China)
range in Shanxi province, China. The name Lüliang Mountains generally refers to the whole system of ranges in the west and southwest of Shanxi, separating the north-south section of the Huang He (Yellow River) to the west from the valley of its tributary, the ...
Lüliang Shan (mountains, China)
range in Shanxi province, China. The name Lüliang Mountains generally refers to the whole system of ranges in the west and southwest of Shanxi, separating the north-south section of the Huang He (Yellow River) to the west from the valley of its tributary, the ...
Luling (China)
city, west-central Jiangxi sheng (province), southeastern China. Ji’an is situated on the west bank of the Gan River, at the head of navigation for small steamboats from Nanchang. The city is a highway centre located on the north-south route up the Gan valley ...
Lull, Ramón (Catalan mystic)
Catalan mystic and poet whose writings helped to develop the Romance Catalan language and widely influenced Neoplatonic mysticism throughout medieval and 17th-century Europe. He is best known in the history of ideas as the inventor of an “art of finding truth” (ars inveniendi veritatis) that was primarily...
Lullaby (work by Gershwin)
...Nobody but You, and Tee-Oodle-Um-Bum-Bo. Also in 1919, Gershwin composed his first “serious” work, the Lullaby for string quartet. A study in harmony that Gershwin composed as an exercise for Kilenyi, Lullaby’s delicate beauty transcends its academic origins. Ira......
Lulli, Giovanni Battista (French composer)
Italian-born French court and operatic composer who from 1662 completely controlled French court music and whose style of composition was imitated throughout Europe....
Lullubi (people)
ancient group of tribes that inhabited the Sherizor plain in the Zagros Mountains of western Iran. A warlike people, they were especially active during the reign of the Akkadian king Naram-Sin (reigned c. 2254–c. 2218 bc) and at the end of the dynasty of Akkad (2334...
Lully, Jean-Baptiste (French composer)
Italian-born French court and operatic composer who from 1662 completely controlled French court music and whose style of composition was imitated throughout Europe....
Lully, Raymond (Catalan mystic)
Catalan mystic and poet whose writings helped to develop the Romance Catalan language and widely influenced Neoplatonic mysticism throughout medieval and 17th-century Europe. He is best known in the history of ideas as the inventor of an “art of finding truth” (ars inveniendi veritatis) that was primarily...
Lulonga River (river, Democratic Republic of the Congo)
stream formed by the union of the Lopori and the Maringa rivers near Basankusu in north-central Congo (Kinshasa), central Africa. It flows 125 miles (200 km) west and southwest to its confluence with the Congo River north of Lulonga. It is navigable fo...
Lulu (British singer and actress)
...by E.R. Braithwaite. With its sentimental story and Poitier’s portrayal of the principled Thackeray, the film was one of the highest-grossing movies of 1967. The title song, which was performed by Lulu, was an international hit. In 1996 Poitier reprised the role of Thackeray in the television movie To Sir, with Love II....
Lulu (opera by Berg)
...(1895; “Earth Spirit”) and Büchse der Pandora (1904; “Pandora’s Box”), he extracted the central figure for his opera Lulu. This work engaged him, with minor interruptions, for the next seven years, and the orchestration of its third act remained incomplete at his death (it was completed by the Austrian....
Lulu (fictional character)
fictional character, an amoral femme fatale who is the protagonist of German dramatist Frank Wedekind’s plays Der Erdgeist (1895; Earth Spirit) and Die Büchse der Pandora (1904; Pandora’s Box)....
Luluabourg (Democratic Republic of the Congo)
city, south-central Democratic Republic of the Congo, situated just east of the Lulua River, a tributary of the Kasai. It is on road and rail routes to Lubumbashi (southeast) and the Kasai River port of Ilebo (northwest) and has air links to those and other Congolese cities. It was named Luluabourg in 1884...
Lulworthiales (order of fungi)
Annotated classification...
lumbago (pathology)
pain in the lower (lumbar) portion of the back. Lumbago is considered by health professionals to be an antiquated term that designates nothing more than lower back pain caused by any of a number of underlying conditions. The pain may be mild or severe, acute or chronic, confined to the lower back or radiating into the buttocks an...
lumbang tree (plant)
...centres, and apple-sized globular fruit. The tung and its relatives, the candlenut tree (Aleurites moluccana), mu tree (A. montana), Japan wood oil tree (A. cordata), and lumbang tree (A. trisperma), are decorative and are planted as shade trees or as sources of tung oil in the subtropical and tropical areas of many countries, including the American Deep South...
lumbar artery (anatomy)
Parietal branches of the abdominal aorta include the inferior phrenic, serving the suprarenal (adrenal) glands, the lumbar, and the middle sacral arteries. The lumbar arteries are arranged in four pairs and supply the muscles of the abdominal wall, the skin, the lumbar vertebrae, the spinal cord, and the meninges (spinal-cord coverings)....
lumbar curve (anatomy)
...more: (1) a sacral curve, in which the sacrum curves backward and helps support the abdominal organs, (2) an anterior cervical curve, which develops soon after birth as the head is raised, and (3) a lumbar curve, also anterior, which develops as the child sits and walks. The lumbar curve is a permanent characteristic only of humans and their bipedal forebears, though a temporary lumbar curve......
lumbar nerve (anatomy)
...pairs of spinal nerves, each of which receives and furnishes one dorsal and one ventral root. On this basis the spinal cord is divided into the following segments: 8 cervical (C), 12 thoracic (T), 5 lumbar (L), 5 sacral (S), and 1 coccygeal (Coc). Spinal nerve roots emerge via intervertebral foramina; lumbar and sacral spinal roots, descending for some distance within the subarachnoid space......
lumbar plexus (anatomy)
Spinal nerves from lumbar levels L1–L4 contribute to the formation of the lumbar plexus, which, along with the sacral plexus, provides motor, sensory, and autonomic fibres to gluteal and inguinal regions and to the lower extremities. Lumbar roots are organized into dorsal and ventral divisions....
lumbar puncture (medical procedure)
direct aspiration (fluid withdrawal) of cerebrospinal fluid (CSF) through a hollow needle. The needle is inserted in the lower back, usually between the third and fourth lumbar vertebrae, into the subarachnoid space of the spinal cord, where the CSF is located....
lumbar vein (anatomy)
...link between the superior and inferior vena cava. The terminal veins of this system are the azygous, hemiazygous, and accessory hemiazygous veins. At the level of the diaphragm, the right ascending lumbar vein continues upward as the azygous vein, principal tributaries of which are the right intercostal veins, which drain the muscles of the intercostal spaces. It also receives tributaries from....
lumbar vertebra (bone anatomy)
...different shapes and functions. Crocodilians and lizards, birds, and mammals demonstrate five regions: (1) cervical, in the neck, (2) thoracic, in the chest, which articulates with the ribs, (3) lumbar, in the lower back, more robust than the other vertebrae, (4) sacral, often fused to form a sacrum, which articulates with the pelvic girdle, (5) caudal, in the tail. The atlas and axis......
lumber (harvested wood)
Collective term for harvested wood, whether cut into logs, heavy timbers, or members used in light-frame construction. Lumber is classified as hardwood or softwood (see wood). The term often refers specifically to the products derived from logs in a sawmill. Conversion of logs to sawed lumber involves debarking, sawing into boards or slabs, resawing into thinner boards of...
Lumberton (North Carolina, United States)
city, seat (1788) of Robeson county, southern North Carolina, U.S., on the Lumber (Lumbee) River about 30 miles (50 km) south of Fayetteville. Founded about 1787 by John Willis, an officer of the American Revolution, it began as a shipping point for lumber and naval supplies floated downriver to Georgetown, South ...
Lumbineris (polychaete genus)
...single-lobed, often with many aciculae (needlelike structures); size, minute to 3 m; examples of genera: Palola (palolo), Eunice, Stauronereis, Lumbineris, Onuphis.Order OrbiniidaSedentary; head pointed or rounded without appendages; proboscis eversibl...
Lumbini (grove, Nepal)
grove near the southern border of modern-day Nepal where, according to Buddhist legend, Queen Maha Maya stood and gave birth to the future Buddha while holding onto a branch of a sal tree. There are two references to Lumbini as the birthplace of the Buddha in the Pali scripture, the firs...
Lumbreras, Luis G. (Peruvian archaeologist)
The next epoch, called the Initial Period by the American scholar John H. Rowe, and the Lower Formative by the Peruvian archaeologist Luis G. Lumbreras, began with the introduction of pottery. The earliest ceramics have yielded radiocarbon dates of about 1800 bc, although Rowe has suggested that even a date of 2100 bc is plausible. Ceramics from this period have been fo...
Lumbriculida (oligochaete order)
...reproduction by copulation, with fertilized eggs laid in a cocoon secreted by clitellum; development direct, without larval stages; about 3,250 living species.Order Lumbriculida (earthworms)Male gonopores several segments behind segments containing the testes or, when 2 pairs of testes are present, in more......
Lumbricus (oligochaete genus)
...the testes or, when 2 pairs of testes are present, in more posterior segment; size, minute to 30–40 cm; examples of genera: Haplotaxis, Eisenia, Lumbricus (earthworm), Megascolides.Order MoniligastridaMale gonopores, 1 or 2 pairs on segment posterior to testes;...
Lumbricus terrestris (earthworm)
any worm of the subclass Oligochaeta (class Clitellata, phylum Annelida). About 3,500 living species are known, the most familiar of which is the earthworm (q.v.), Lumbricus terrestris. Oligochaetes are common all over the world. They live in the sea, in fresh water, and in moist soil....
Lumbwa (people)
largest ethnic group of the Southern Nilotic (Kalenjin) language group. They occupy the highlands around the town of Kericho in southwestern Kenya. Like other Nandi speakers, they originated in the highlands north of Lake Rudolf (Lake Turkana) and move...
Lumbye, H. C. (Danish composer)
The park was opened in 1843 by the writer-architect Georg Carstensen (1812–59) on the southern ramparts of the old city. A remnant of the former moat became a lake for boating. The composer H.C. Lumbye (1810–74) conducted the orchestra at Tivoli for its first 30 years, playing popular Viennese dance music as well as his own compositions. Bombing in 1944 destroyed many park......
lumen (unit of energy measurement)
unit of luminous flux, or amount of light, defined as the amount streaming outward through one steradian (a unit of solid angle, part of the volume of space illuminated by a light source) from a uniform point source having an intensity of one candela. The lumen is used in calculations regarding artificial lighting. ...
lumen (anatomy)
...and the prominence more marked in men than in women, which has given this structure the common name of Adam’s apple. Behind the shieldlike thyroid cartilage, the vocal cords span the laryngeal lumen. They correspond to elastic ligaments attached anteriorly in the angle of the thyroid shield and posteriorly to a pair of small pyramidal pieces of cartilage, the arytenoid cartilages. The......
Lumen Gentium (Roman Catholicism)
...Activity (Ad Gentes) built theologically on the council’s foundational document, the “Dogmatic Constitution on the Church” (Lumen Gentium; “Light of the Nations”), which insisted upon evangelization but presented a larger understanding of God’s grace for those outside the church, and urge...
Lumet, Sidney (American director)
American motion-picture, television, and stage director noted for his psychological dramas. He was one of the most prolific and important American cinematic directors of the second half of the 20th century....
Lumière, Auguste (French inventor)
...15 million plates a year. That year the father, Antoine, was invited to a showing of Thomas Edison’s Kinetoscope in Paris; his description of the peephole machine on his return to Lyon set Louis and Auguste to work on the problem of combining animation with projection. Louis found the solution, which was patented in 1895. At that time they attached less importance to this invention than ...
Lumière brothers (French inventors)
French inventors and pioneer manufacturers of photographic equipment who devised an early motion-picture camera and projector called the Cinématographe (“cinema” is derived from this name). Auguste Lumière (b. Oct. 19, 1862Besançon, France—d. Apr...
Lumière, Louis (French inventor)
Sons of a painter turned photographer, the two boys displayed brilliance in science at school in Lyon, where their father had settled. Louis worked on the problem of commercially satisfactory development of film; at 18 he had succeeded so well that with his father’s financial aid he opened a factory for producing photographic plates, which gained immediate success. By 1894 the Lumièr...
Lumières, Siècle de (European history)
a European intellectual movement of the 17th and 18th centuries in which ideas concerning God, reason, nature, and man were synthesized into a worldview that gained wide assent and that instigated revolutionary developments in art, philosophy, and politics. Central to Enlightenment thought were the use and the celebration of reason, the power by which man understands the univers...
luminaire (lighting)
Complete lighting unit, consisting of one or more lamps (bulbs or tubes that emit light), along with the socket and other parts that hold the lamp in place and protect it, wiring that connects the lamp to a power source, and a reflector that helps direct and distribute the light. Fluorescent fixtures usually have lenses or louvers to shield th...
luminance (physics)
...Light and dark colours that have the same chromaticity (and are therefore plotted at the same point on the two-dimensional chromaticity diagram) are distinguished by their different Y values (luminance, or visually perceived brightness)....
luminance signal (electronics)
The picture carrier is thus simultaneously amplitude modulated by (1) the luminance signal, to represent changes in the intended luminance, and (2) the chrominance subcarrier, which in turn is amplitude modulated to represent changes in the intended saturation and phase modulated to represent changes in the intended hue. When a colour receiver is tuned to the transmission, the picture signal is......
luminance transmission (electronics)
...or luminance, of the televised scene, and the other carries the colour, or chrominance, information. Since the ability of the human eye to perceive detail is most acute when viewing white light, the luminance transmission carries the impression of fine detail. Because it employs methods essentially identical to those of a monochrome television system, it can be picked up by black-and-white......
luminescence (physics)
emission of light by certain materials when they are relatively cool. It is in contrast to light emitted from incandescent bodies, such as burning wood or coal, molten iron, and wire heated by an electric current. Luminescence may be seen in neon and fluorescent lamps; television, radar, and X-ray fluoroscope screens; organi...
luminescence, biological (chemical reaction)
the emission of light by an organism or by a test-tube biochemical system derived from an organism. It could be the ghostly glow of bacteria on decaying meat or fish, the shimmering phosphorescence of protozoans in tropical seas, or the flickering signals of fireflies. The phenomenon occurs sporadically in a wide range of protists and animals, from bacteria and fungi to insects, marine invertebrat...
luminescent lamp
Luminescent lamps, which produce less heat than incandescent lamps, include electric discharge lamps, semiconductor lamps, and chemical lamps. Of the electric discharge lamps, the fluorescent lamp (q.v.) gives off a neutral white light, the sodium-vapour lamp emits a yellow-orange light, and the mercury-vapour lamp gives off a whitish blue-green light....
luminiferous ether (theoretical substance)
in physics, a theoretical, universal substance believed during the 19th century to act as the medium for transmission of electromagnetic waves (e.g., light and X rays) much as sound waves are transmitted by elastic media such as air. The ether was assumed to be weightless, transparent, frictionless,...
luminism (painting)
late 19th-century painting style emphasizing a unique clarity of light. It was characteristic of the works of a group of independent American painters who were directly influenced by the Hudson River school of painting. The term, however, was not coined until 1954 by John Baur, director of the ...
Luminodesmus sequoiae (millipede)
...habitat, but almost all these forms are nocturnal. The centipede Orphaneus, widely distributed in tropical Asia, gives off luminous secretions from each segment. The entire body of Luminodesmus sequoiae, a millipede found in the Sierra Nevada (mountains) of California, glows with a diffuse light. Luminous insects include some true flies (order Diptera), notably......
luminol (chemical compound)
The first efficient chemiluminescent materials were nonbiological synthetic compounds such as luminol (with the formula 5-amino-2,3-dihydro-1.4-phthalazinedione). The strong blue chemiluminescence resulting from oxidation of this compound was first reported in 1928....
luminosity (astronomy)
in astronomy, the amount of light emitted by an object in a unit of time. The luminosity of the Sun is 3.846 × 1026 watts (or 3.846 × 1033 ergs per second). Luminosity is an absolute measure of radiant power; that is, its value is independent of an observer’s distance from an object. Astronomers usu...
luminosity function (astronomy)
The stellar luminosity function is a description of the relative number of stars of different absolute luminosities. It is often used to describe the stellar content of various parts of the Galaxy or other groups of stars, but it most commonly refers to the absolute number of stars of different absolute magnitudes in the solar neighbourhood. In this form it is usually called the van Rhijn......
luminous flux (physics)
The stellar luminosity function is a description of the relative number of stars of different absolute luminosities. It is often used to describe the stellar content of various parts of the Galaxy or other groups of stars, but it most commonly refers to the absolute number of stars of different absolute magnitudes in the solar neighbourhood. In this form it is usually called the van Rhijn.........
luminous intensity (physics)
the quantity of visible light that is emitted in unit time per unit solid angle. The unit for the quantity of light flowing from a source in any one second (the luminous power, or luminous flux) is called the lumen. The lumen is evaluated with reference to visual sensation. The sensitivity of the human eye is greatest for l...
luminous moss (plant species)
(Schistostega pennata; formerly S. osmundacea), light-reflecting plant of the subclass Bryidae, native to the Northern Hemisphere. It forms green mats in caves, holes in wood or earth, or cavities between rocks or under tree roots. A luminous moss is about one centimetre (12 inch) or more tall. The lower part of the caulid (stem) is bare, and the up...
luminous mysteries (religion)
In 2002 Pope John Paul II added a fourth set of mysteries, the “luminous mysteries,” or mysteries of light. The five new mysteries celebrate events in Jesus’ ministry, including his baptism; his miracle at Cana, where he turned water into wine; his proclamation of the kingdom of God; the Transfiguration, in which he revealed his divinity to three of his Apostles; and his......
luminous paint
paint that glows in the dark because it contains a phosphor, a substance that emits light for a certain length of time after exposure to an energy source, such as ultraviolet radiation. Zinc sulfide and calcium sulfide are such phosphors....
luminous range (light)
The luminous intensity of a light, or its candlepower, is expressed in international units called candelas. Intensities of lighthouse beams can vary from thousands to millions of candelas. The range at which a light can be seen depends upon atmospheric conditions and elevation. Since the geographic horizon is limited by the curvature of the Earth, it can be readily calculated for any elevation......
Luminy (France)
...complexes in Marseille, the North Hospital and the Timone Hospital. The centre for the study of tropical medicine at the Michel Lévy Hospital is well known. A computer centre in the suburb of Luminy links the region’s hospitals....
lumirhodopsin (protein)
...changes may be arrested by cooling the solution to -195° C (-319° F), at which temperature prelumirhodopsin remains stable; on warming to -140° C (-220° F) prelumirhodopsin becomes lumirhodopsin, with a slightly different colour; on warming further, successive changes are permitted until finally retinal is split off from the opsin to give a yellow solution. The impor...
Lumizip 900 (typesetter)
...performs at the rate of 70,000 to 80,000 characters per hour. But at this speed the technique of using a rotary matrix case reaches its limit because of the problems posed by centrifugal force. The Lumizip 900 (1959) introduced a further revolutionary change by retaining as moving parts only the lens, which scans in a single movement the fixed series of light matrices so as to photograph at one...
Lumley, Harry (American hockey player)
American hockey goalie whose 16 seasons in the National Hockey League included an important role in the 1950 Stanley Cup victory of the Detroit Red Wings as well as selection to the All-Star team three times; he was inducted into the Hockey Hall of Fam...
Lumley, Joanna (British actress)
May 1, 1946Srinagar, Kashmir, British IndiaIn early 2009 Joanna Lumley, a tall, blonde British comedic actress, accomplished something that is achieved by very few people—including individual MPs. She pressured the U.K. government to abandon a specific policy and change course. Her cause was that of supporting the Gurkha soldiers...
Lumley, Joanna Lamond (British actress)
May 1, 1946Srinagar, Kashmir, British IndiaIn early 2009 Joanna Lumley, a tall, blonde British comedic actress, accomplished something that is achieved by very few people—including individual MPs. She pressured the U.K. government to abandon a specific policy and change course. Her cause was that of supporting the Gurkha soldiers...
Lummis, Elizabeth Fries (American author)
American historical writer, best remembered for her several extensive volumes of portraits of American women of the Revolutionary War and of Western pioneer days....