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  • double cross (genetics)

    origins of agriculture: Maize, or corn: The double cross was the basic technique used in developing modern hybrid maize and has been used by commercial firms since. Jones’s invention was to use four inbred lines instead of two in crossing. Simply, inbred lines A and B made one cross, lines C and…

  • double cross hybrid (genetics)

    origins of agriculture: Maize, or corn: The double cross was the basic technique used in developing modern hybrid maize and has been used by commercial firms since. Jones’s invention was to use four inbred lines instead of two in crossing. Simply, inbred lines A and B made one cross, lines C and…

  • Double Crostic (puzzle)

    acrostic: In the United States, the Double Crostic puzzle, devised by Elizabeth Kingsley for the Saturday Review in 1934, had an acrostic in the answers to the clues giving the author and title of a literary work; the letters, keyed by number to blanks like those of a crossword puzzle, spelled…

  • double curtal (musical instrument)

    wind instrument: The Renaissance: …its bass (sometimes called the double curtal in England and the Choristfagott in Germany) soon became the most important size, particularly at the beginning of the Baroque period, when it was needed for a bass whenever higher winds were scored. German church composers of the 17th century normally used the…

  • double dactyls (literature)

    Double dactyls, a light-verse form consisting of eight lines of two dactyls each, arranged in two stanzas. The first line of the poem must be a jingle, often “Higgledy-piggledy,” “Jiggery-pokery,” or “Pocketa-pocketa”; the second line must be a name; and the last lines of each stanza are truncated

  • double diffraction system (optics)

    optics: Filtering: Maréchal gave the descriptive title double diffraction to this type of two-lens system.

  • double displacement (chemistry)

    organometallic compound: Double displacement: The synthesis of organometallic compounds by double displacement involves organometallic (MR) and binary halide (EX, where E is a metal or metalloid and X is a halogen) starting materials. It provides a convenient synthetic procedure that is widely used in the laboratory and…

  • double Dutch (game)

    Double Dutch, children’s game in which the player must time jumps between two jump ropes twirling in opposite directions. In the 1930s, during the Depression era, children often jumped rope because the game required only a used clothesline to be played. By the late 1950s, however, a number of

  • Double Dutch (work by Shonibare)

    Yinka Shonibare: In paintings such as Double Dutch (1994), he created a large work by painting a rectangle on a wall and placing on it a grid of several small stretchers covered with the Dutch wax-printed fabric ubiquitous in his art. He then began using these textiles to create costumes in…

  • Double Dynamite (film by Cummings [1951])

    Irving Cummings: …he made the strained comedy Double Dynamite, starring Jane Russell, Frank Sinatra, and Groucho Marx. Cummings subsequently retired from directing.

  • Double Eagle V (balloon)

    Ben L. Abruzzo: …nonstop balloon flight, in the Double Eagle V.

  • double effect, doctrine of (ethics)

    ethics: Natural law ethics: …situation in which the so-called doctrine of double effect would apply. If a pregnant woman, for example, is found to have a cancerous uterus, the doctrine of double effect allows a doctor to remove it, notwithstanding the fact that such action would kill the fetus. This allowance is made not…

  • Double Falsehood (play)

    Double Falsehood, tragicomedy in five acts presented by Lewis Theobald at Drury Lane Theatre in 1727. According to Theobald, it was based on a lost play by William Shakespeare (and, scholars now believe, John Fletcher) called Cardenio. The play was probably first performed (as Cardenio) in 1613,

  • Double Falsehood; or, The Distressed Lovers (play)

    Double Falsehood, tragicomedy in five acts presented by Lewis Theobald at Drury Lane Theatre in 1727. According to Theobald, it was based on a lost play by William Shakespeare (and, scholars now believe, John Fletcher) called Cardenio. The play was probably first performed (as Cardenio) in 1613,

  • Double Fantasy (album by Lennon and Ono)

    John Lennon: … (1970) through his half of Double Fantasy (1980)—reflects Ono’s belief in art without artifice. Whether or not they actually eschewed artifice, that was one impression they strove to create.

  • double feature (theatrical attraction)

    history of the motion picture: The Hollywood studio system: The double feature, an attraction introduced in the early 1930s to counter the Depression-era box-office slump, was the standard form of exhibition for about 15 years. The larger studios were, for the most part, not interested in producing B movies for double bills, because, unlike the…

  • double fertilization (biology)

    angiosperm: Fertilization and embryogenesis: This is called double fertilization because the true fertilization (fusion of a sperm with an egg) is accompanied by another fusion process (that of a sperm with the polar nuclei) that resembles fertilization. Double fertilization of this type is unique to angiosperms. The zygote now has a full…

  • double flower (plant anatomy)

    Asteraceae: Flowers: These “double-flowered” forms do not survive competition in nature, but they are valued and perpetuated horticulturally because of their showier flower heads. The “daisy-flowered” chrysanthemums, with only a single marginal row of ray flowers, have the normal type of radiate head, but the more commonly cultivated…

  • double fugue (music)

    fugue: Varieties of the fugue: In a double fugue two subjects may receive simultaneous exposition; the result is similar to a simple fugue with a countersubject, as is the case in the opening chorus of Bach’s St. Matthew Passion, BWV 244 (1727; Passio secundum Matthaeum). More often, in a double fugue the…

  • double glazing (construction)

    art conservation and restoration: Glass and other vitreous materials: Double-glazing can be quite successful in some instances for protecting stained-glass windows from the damaging effects of exterior (and even interior) environments. The process involves placing a clear pane of glass over the original stained glass with a suitable space for air circulation to prevent…

  • double harp (musical instrument)

    harp: , the double harp, with two rows of strings, and the Welsh triple harp, with three rows. They also include the chromatic harp, invented in the late 19th century by the Pleyel firm of Paris, with two crossing sets of strings (like an X), and its U.S.…

  • double helix (genetics)

    James Watson: …a molecular model for DNA—a double helix, which can be likened to a spiraling staircase or a twisting ladder. The DNA double helix consists of two intertwined sugar-phosphate chains, with the flat base pairs forming the steps between them. Watson and Crick’s model also shows how the DNA molecule could…

  • Double Helix, The (work by Watson)

    James Watson: He later wrote The Double Helix (1968), an informal personal account of the DNA discovery and the roles of the people involved in it, which aroused some controversy.

  • double hernia (physiology)

    hernia: …bilaterally, it is called a double hernia. A femoral hernia lies on the inner side of the large femoral blood vessels of the thigh. An umbilical hernia protrudes through the navel.

  • Double Hook, The (novel by Watson)

    Canadian literature: Modern period, 1900–60: Sheila Watson’s enigmatic and mythic The Double Hook (1959) and Ethel Wilson’s Swamp Angel (1954), about a Vancouver housewife’s bid for personal freedom, present quest journeys against the striking backdrop of British Columbia’s interior. Elizabeth Smart’s incantatory novel By Grand Central Station I Sat Down and Wept (1945) is a…

  • double hull (ship part)

    tanker: …but the smallest ships have double hulls or some suitable equivalent. (In a double-hulled ship, the sides and bottom consist of two layers separated by a space sufficient to reduce the chance that an incident breaching one layer will breach the other.) After 1996 all new tankers were delivered with…

  • double hybrid (genetics)

    origins of agriculture: Maize, or corn: The double cross was the basic technique used in developing modern hybrid maize and has been used by commercial firms since. Jones’s invention was to use four inbred lines instead of two in crossing. Simply, inbred lines A and B made one cross, lines C and…

  • Double Indemnity (novel by Cain)

    James M. Cain: …were made from his novels: Double Indemnity (1936; film 1944), Mildred Pierce (1941; film 1945, TV miniseries 2011), and The Postman Always Rings Twice (1934; stage version 1936, films 1946, 1981).

  • Double Indemnity (film by Wilder [1944])

    Double Indemnity, American film noir, released in 1944, that was considered the quintessential movie of its genre. It followed the time-honoured noir plotline of a man undone by an evil woman. The film was adapted by director Billy Wilder and writer Raymond Chandler from the 1935 novella by James

  • double indemnity rider

    insurance: Special riders: Under the double indemnity rider, if death occurs through accident, the insurance payable is double the face amount.

  • double iron (tool)

    hand tool: Plane: Now called the double iron, it is a feature of all but the smallest of modern planes.

  • double jeopardy (law)

    Double jeopardy, in law, protection against the use by the state of certain multiple forms of prosecution. In general, in countries observing the rule of double jeopardy, a person cannot be tried twice for the same crime based on the same conduct. If a person robs a bank, that individual cannot

  • Double Jeopardy (film by Beresford [1999])

    Tommy Lee Jones: …convicted murderer (Ashley Judd) in Double Jeopardy (1999) and as a man attempting to find his kidnapped granddaughter in the western The Missing (2003). He then directed and starred in the grim drama The Three Burials of Melquiades Estrada (2005), which traces the efforts of a rancher to return the…

  • double knit (textile)

    knitting: Double knits are heavy and firm and rarely run. They are produced only by machine, with a variation of the rib stitch, the interlock stitch, employing two yarns and two sets of needles, with loops drawn through from both directions.

  • double leachate collection system (waste management)

    hazardous-waste management: Secure landfills: The double leachate collection system consists of a network of perforated pipes placed above each liner. The upper system prevents the accumulation of leachate trapped in the fill, and the lower serves as a backup. Collected leachate is pumped to a treatment plant. In order to…

  • Double Life of Veronique, The (film by Kie?lowski [1991])

    Krzysztof Kie?lowski: …Double Vie de Véronique (1991; The Double Life of Veronique) came commercial as well as critical success. This moody, atmospheric film is the study of two doppelg?ngers—one French, one Polish—who, in addition to sharing the same name, share the same birthday, heart condition, and a vague sense of the existence…

  • Double Life, A (film by Cukor [1947])

    A Double Life, American drama film, released in 1947, that is notable for Ronald Colman’s Academy Award-winning portrayal of an unstable stage actor. Colman played Anthony John, an acclaimed star of the theatre who takes on the persona of the role he is currently playing. Thus, he can be

  • Double Man, The (film by Schaffner [1967])

    Franklin J. Schaffner: Less popular was The Double Man (1967), an espionage drama with Yul Brynner in a dual role as an American and an East German spy.

  • Double Man, The (work by Auden)

    W. H. Auden: Life: …songs and topical verse, and The Double Man (containing “New Year Letter,” which provided the title of the British edition; 1941) embodies his position on the verge of commitment to Christianity. The beliefs and attitudes that are basic to all of Auden’s work after 1940 are defined in three long…

  • double negation, law of (logic)

    formal logic: Logical manipulations in LPC: Similarly, because the law of double negation permits the deletion of a pair of consecutive negation signs, ~(?x) may be replaced by (?x)~, and ~(?x) by (?x)~.

  • Double Negative (work by Heizer)

    Western painting: Land art: Michael Heizer’s Double Negative (1969–70) involved the removal of thousands of tons of earth in order to produce two “cuts” that faced each other across the chasm of the Mormon Mesa in Nevada. Bulgarian-born artist Christo and Jeanne-Claude, his Moroccan-born wife, specialized throughout the 1960s and ’70s…

  • double numerical integration (technology)

    inertial guidance system: Double numerical integration, combining the measured accelerations and the instantaneous turning rates, allows the computer to determine the craft’s current velocity and position and to guide it along the desired trajectory.

  • Double Persephone (poetry by Atwood)

    Margaret Atwood: In her early poetry collections, Double Persephone (1961), The Circle Game (1964, revised in 1966), and The Animals in That Country (1968), Atwood ponders human behaviour, celebrates the natural world, and condemns materialism. Role reversal and new beginnings are recurrent themes in her novels, all of them centred on women…

  • double play (baseball)

    baseball: The force play: …outs on one play, a double play. Although double plays can be initiated by force outs at home or third base, the second-to-first double play is the most common form.

  • double predestination (religion)

    predestination: …extreme is the notion of double predestination, commonly identified with Calvinism and especially associated with the Synod of Dort (1618–19) and appearing also in some of the writings of St. Augustine and Martin Luther and in the thought of the Jansenists. According

  • double reed (musical instrument part)

    wind instrument: Flutes and reeds: …beating parts of a multiple reed or between a beating single reed and a mouthpiece.

  • double refraction (optics)

    Double refraction, an optical property in which a single ray of unpolarized light entering an anisotropic medium is split into two rays, each traveling in a different direction. One ray (called the extraordinary ray) is bent, or refracted, at an angle as it travels through the medium; the other ray

  • double replacement

    organometallic compound: Alkylidene ligands: …Schrock carbenes is the alkene metathesis reaction:

  • double retting (fibre-separation process)

    retting: In double retting, a gentle process producing excellent fibre, the stalks are removed from the water before retting is completed, dried for several months, then retted again.

  • double rhyme (prosody)

    Feminine rhyme, in poetry, a rhyme involving two syllables (as in motion and ocean or willow and billow). The term feminine rhyme is also sometimes applied to triple rhymes, or rhymes involving three syllables (such as exciting and inviting). Robert Browning alternates feminine and masculine rhymes

  • Double Ring Storage Facility (collider)

    DESY: The Double Ring Storage Facility (DORIS), completed 10 years later, was designed to collide beams of electrons and positrons at energies of 3.5 GeV per beam (upgraded to 5 GeV per beam in 1978). Now in its third version as DORIS III, this machine is no…

  • Double Sextet (work by Reich)

    Steve Reich: His composition Double Sextet (2007), arranged either for 12 musicians or for 6 playing against a recording of themselves, won the 2009 Pulitzer Prize for Music. In commemoration of the September 11, 2001, attacks on the World Trade Center, Reich composed WTC 9/11: For Three String Quartets…

  • double stage (theatrical device)

    theatre: Development of stage equipment: Elevator stages permitted new settings to be assembled below stage and then lifted to the height of the stage as the existing setting was withdrawn to the rear and dropped to below-stage level. Slip stages allowed large trucks to be stored in the wings or…

  • double standard (sexual morality)

    human sexual activity: Sociosexual activity: This double standard of morality is also seen in premarital life. Postmarital coitus (i.e., coitus by separated, divorced, or widowed persons) is almost always ignored. Even societies that try to confine coitus to marriage recognize the difficulty of trying to force abstinence upon sexually experienced and…

  • double standard (monetary system)

    Bimetallism, monetary standard or system based upon the use of two metals, traditionally gold and silver, rather than one (monometallism). The typical 19th-century bimetallic system defined a nation’s monetary unit by law in terms of fixed quantities of gold and silver (thus automatically

  • double star (astronomy)

    binary star: …binary stars are sometimes called double stars, the latter refers to any two stars that are close together in the sky and thus includes true binaries as well as stars that look close together when viewed from Earth but which are actually quite far apart.

  • double star (astronomy)

    Binary star, pair of stars in orbit around their common centre of gravity. A high proportion, perhaps one-half, of all stars in the Milky Way Galaxy are binaries or members of more complex multiple systems. Although binary stars are sometimes called double stars, the latter refers to any two stars

  • double sugar (biochemistry)

    Disaccharide, any substance that is composed of two molecules of simple sugars (monosaccharides) linked to each other. Disaccharides are crystalline water-soluble compounds. The monosaccharides within them are linked by a glycosidic bond (or glycosidic linkage), the position of which may be

  • Double Suicide at Amijima (work by Chikamatsu)

    The Love Suicides at Amijima, classic Bunraku (puppet theatre) play by Chikamatsu Monzaemon, written and performed about 1720 as Shinjū ten no Amijima. Like most of Chikamatsu’s more than 20 love-suicide dramas, it was based on an actual event, the outcome of the brothel system. These works made

  • double taxation

    Double taxation, in economics, situation in which the same financial assets or earnings are subject to taxation at two different levels (e.g., personal and corporate) or in two different countries. The latter can occur when income from foreign investments is taxed both by the country in which it is

  • double tide (physics)

    English Channel: Hydrology: …at Southampton, which has a double, or prolonged, high tide), and the Gulf of Saint-Malo experiences the greatest tidal range, 28 feet or more.

  • Double Trouble (film by Taurog [1967])

    Norman Taurog: Elvis movies: …completed Taurog’s career: Spinout (1966), Double Trouble (1967), Speedway (1968), and Live a Little, Love a Little (1968).

  • double unilineal descent (sociology)

    descent: In systems of double unilineal descent, society recognizes both the patrilineage and the matrilineage but assigns to each a different set of expectations. For example, the inheritance of immovable materials, such as land, may be the domain of the patrilineage, while the matrilineage controls the inheritance of moveable…

  • Double Vie de Véronique, La (film by Kie?lowski [1991])

    Krzysztof Kie?lowski: …Double Vie de Véronique (1991; The Double Life of Veronique) came commercial as well as critical success. This moody, atmospheric film is the study of two doppelg?ngers—one French, one Polish—who, in addition to sharing the same name, share the same birthday, heart condition, and a vague sense of the existence…

  • double virginal (musical instrument)

    Hans Ruckers, the Elder: …earliest known instrument is a double virginal (a rectangular harpsichord with two independent keyboards, set side by side, and two independent sets of strings) dated 1581, now in New York City; his latest extant instrument is dated 1620. Ruckers’ sons Hans the Younger (also known as Jean) and Andreas were…

  • double vision (physiology)

    Double vision, perceiving of two images of a single object. Normal binocular vision results from the brain’s fusion of slightly different images from each eye, with points on the retina of each eye corresponding to points on the retina of the opposite eye. Binocular diplopia occurs when the eyes

  • double warp (textiles)

    Bījār carpet: …carpets are said to be double warped. This refers to the way the warps are strung closely together, and alternate weft shoots are pulled so tight that the warp lies on two levels, one almost precisely behind the other. The structure is unusual in that the weft is passed three…

  • Double X (American baseball player)

    Jimmie Foxx, American professional baseball player, the second man in major league history to hit 500 home runs. (Babe Ruth was the first.) A right-handed hitter who played mostly at first base, he finished with a total of 534 home runs. His career batting average was .325. Foxx was a sensational

  • Double, The (novel by Dostoyevsky)

    The Double, novel by Fyodor Dostoyevsky, published in 1846 in Russian as Dvoynik. It is a classic of doppelg?nger literature. The Double is the first of many works by Dostoyevsky to reveal his fascination with psychological doubles. The morbidly sensitive and pretentious clerk Golyadkin, already

  • double-acting baking powder

    leavening agent: Double-acting baking powder, the most widely used type, contains sodium aluminum sulfate and calcium acid phosphate and releases a small amount of gas when mixed and the balance when heated.

  • double-acting engine

    James Watt: The Watt engine: …inventive powers, he patented the double-acting engine, in which the piston pushed as well as pulled. The engine required a new method of rigidly connecting the piston to the beam. He solved that problem in 1784 with his invention of the parallel motion—an arrangement of connected rods that guided the…

  • double-acting pump

    pump: Positive displacement pumps.: …of this type are called double acting. Fluctuations in pumping rate can be further reduced by using more than one cylinder.

  • double-action accordion (musical instrument)

    accordion: In “double-action” accordions, the two reeds of each pair are tuned to the same note, thus making each treble or bass note available from the same key or button with both directions of bellows movement. Among these instruments is the piano accordion, with a piano-style keyboard…

  • double-aspect theory (philosophy)

    Double-aspect theory, type of mind-body monism. According to double-aspect theory, the mental and the material are different aspects or attributes of a unitary reality, which itself is neither mental nor material. The view is derived from the metaphysics of Benedict de Spinoza, who held that mind

  • double-banded courser (bird)

    charadriiform: Shorebirds (suborder Charadrii): …lay two eggs, but the double-banded courser (Rhinoptilus africanus) lays only one, often located near antelope droppings, for concealment on otherwise bare ground. In that species, incubation by both sexes lasts about 26 days, and eggshells are removed. The chick has sparse down and is fed for about six weeks,…

  • double-base gunpowder (explosive)

    propellant: … until the 20th century, when double-base gunpowder (40 percent nitroglycerin, 60 percent nitrocellulose) came into use. Other modern solid propellants are cast perchlorate (using perchlorate as oxidizer and various oils or rubbers as fuel) and composite propellants (using a plastic binder with ammonium picrate, potassium nitrate, or sodium nitrate). There…

  • double-bass viol (musical instrument)

    viol: …sizes was later added the violone, a double bass viol often tuned an octave below the bass.

  • double-bit ax (tool)

    hand tool: Early metal designs: The double-bit (two-bladed) ax, classically associated with the Minoans, was first known in 2500 bce as a votive ax, a piece of tomb furniture made of riveted bronze plates. It became a working tool when it was cast in bronze with a shaft hole about 500…

  • double-blind trial (science)

    therapeutics: Designing a therapeutic regimen: Such a study is “double-blind”: it controls for both possible tendencies by comparing an active drug with an inactive placebo (an inert drug). Neither the patient nor the physician knows which drug the patient is taking, so that neither one’s bias can influence the result. Although this is the…

  • double-chair (carriage)

    Curricle, open, two-wheeled gentleman’s carriage, popular in England from about 1700 to 1850. It was pulled by two matched horses yoked abreast and was therefore equipped with a pole, rather than shafts. The pole had to be very strong because it both directed the carriage and bore its weight. To

  • double-contrast barium enema (medical procedure)

    colorectal cancer: Diagnosis: An X-ray procedure called a double-contrast barium enema may be used. Barium sulfate is used to coat the colon, and the colon is filled with air. A series of X rays are then taken, and the resulting high-contrast images indicate any abnormalities present.

  • double-crucible technique (technology)

    industrial glass: Fabrication: …also are made by the double-crucible technique (see Figure 11), in which two concentric compartments of a platinum crucible are fed with glass rods, and a composite stream is allowed to exit a bottom orifice. In either case, the glass fibre is attenuated to its proper dimensions by a high-speed…

  • Double-Dealer, The (play by Congreve)

    William Congreve: Literary career: His next play, The Double-Dealer, played in November or December at Drury Lane but did not meet with the same applause (it later became the more critically admired work, however). Its published form contained a panegyrical introduction by Dryden. Love for Love almost repeated the success of his…

  • double-deck car (railroad vehicle)

    railroad: Cars for daytime service: …is an increasing use of double-deck cars for such operations in North America, Europe, and Australia. North American operators have tended to prefer a design that limits the upper level to a gallery along each side wall, but in most double-deck cars the upper level is wholly floor-separated from the…

  • double-deck elevator

    elevator: …of the idea of the double-deck elevator, first tried in 1932. Each elevator consisted of two cars, one mounted above the other and operating as a unit, serving two floors at each stop. The technique is being increasingly adopted. Automatic double-deck elevators in the Time-Life Building, Chicago, were operating in…

  • double-deck pinochle (card game)

    pinochle: Partnership pinochle: …been eclipsed in popularity by double-deck pinochle, in which the 9s are stripped from two standard pinochle decks to produce an 80-card deck. Besides the basic melds, there exist triple aces (150 points for three in each suit), triple kings (120), triple queens (90), triple jacks (60), triple pinochles (45…

  • double-dummy problem (bridge)

    bridge: Bridge problems: …is enhanced by study of double-dummy problems (in which the location of all unplayed cards is known). Putting such knowledge to practical use has been much better accomplished in contract bridge than in any of its predecessor games. For example, a prime problem at whist was the “Great Vienna Coup,”…

  • double-elimination tournament (sports and games event)

    tournament: In some tournaments, called double-elimination tournaments, the contestant is not eliminated until defeated a second time. In a third form, called a round robin, each contestant opposes every other contestant and the one with the highest percentage of victories is declared the champion.

  • double-ender ferry (type of ship)

    ship: Ferries: …of ferry is the “double-ender,” built for shuttling across harbour waters. The typical vessel has propellers, rudders, control stations, and loading ramps at both ends. It is usually wide enough to handle four vehicle lanes abreast and may accommodate up to 100 four-wheeled vehicles. Special docks, fitted with adjustable…

  • double-entry bookkeeping

    balance of payments: …presented in the form of double-entry bookkeeping.

  • double-figure impost (art)

    Iranian art and architecture: Architecture: …Achaemenian design is the “double-figure” impost (an upper addition to the capital), taking the form of paired bulls, bull-men, or dragons. Some of these features reappear in the contemporary palace at Susa. Also from this source are figured panels of molded and glazed brick, reminiscent of Nebuchadrezzar’s Babylon.

  • double-focusing mass spectrometer (instrument)

    mass spectrometry: Focusing spectroscopes: Such focusing is termed double focusing. It was thus possible to achieve a resolving power of about 60,000.

  • double-headed drum (musical instrument)

    percussion instrument: Membranophones: Double-headed drums served to provide rhythmic accompaniment in the Middle Ages, and in the 7th century is found the first evidence of their being played with drumsticks, a technique adopted from Asia. The small rope-strung cylinder drum known as the tabor entered western Europe during…

  • double-pipe heat exchanger

    heat exchanger: …is the concentric tube or double-pipe heat exchanger shown in Figure 1, in which one pipe is placed inside another. Inlet and exit ducts are provided for the two fluids. In the diagram the cold fluid flows through the inner tube and the warm fluid in the same direction through…

  • double-stranded RNA (biochemistry)

    RNA interference: …introducing short double-stranded RNA (dsRNA) segments into the cells of nematodes (Caenorhabditis elegans). The dsRNA segments underwent enzymatic processing that enabled them to attach to molecules of messenger RNA (mRNA) possessing complementary nucleotide sequences. The attachment of the two RNAs inhibited the translation of the mRNA molecules into proteins

  • double-striped thickknee (bird)

    thickknee: The double-striped thickknee (B. bistriatus) inhabits the American tropics. Others are the great stone curlew (Esacus recurvirostris), also called stone plover or reef thickknee, of coastal rivers of India; and the beach stone curlew (Orthorhamphus magnirostris) of Australia.

  • double-system recording (cinematic process)

    motion-picture technology: Double-system recording: Although it is possible to reproduce sound, either optically or magnetically, in the same camera that is photographing a scene (a procedure known as single-system recording), there is greater flexibility if the sound track is recorded by a different person and on a…

  • double-system shooting (cinematic process)

    motion-picture technology: Double-system recording: Although it is possible to reproduce sound, either optically or magnetically, in the same camera that is photographing a scene (a procedure known as single-system recording), there is greater flexibility if the sound track is recorded by a different person and on a…

  • double-truth theory (philosophy)

    Double-truth theory, in philosophy, the view that religion and philosophy, as separate sources of knowledge, might arrive at contradictory truths without detriment to either—a position attributed to Averro?s and the Latin Averroists. Perhaps neither Averro?s, a Muslim philosopher, nor the Christian

  • double-wattled cassowary (bird)

    cassowary: The common, or southern, cassowary, Casuarius casuarius, which inhabits New Guinea, nearby islands, and Australia, is the largest—almost 1.5 metres (5 feet) tall—and has two long red wattles on the throat. The dwarf cassowary (C. bennetti) is native to higher elevations of New Guinea and can…

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