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  • Bach, Alexander, Freiherr von (Austrian statesman)
    Under Francis Joseph and Schwarzenberg, order was restored. Schwarzenberg died in 1852, and the new regime passed largely to the direction of Alexander, Freiherr (baron) von Bach, minister of the interior and a competent bureaucrat. Despite its reputation as a repressive instrument, Bach’s government was not without positive accomplishments. It established a unified customs territory for th...
  • Bach, Carl Philipp Emanuel (German composer)
    second surviving son of J.S. and Maria Barbara Bach, and the leading composer of the early Classical period....
  • Bach, Johann Christian (German composer)
    composer called the “English Bach,” youngest son of J.S. and Anna Magdalena Bach and prominent in the early Classical period....
  • Bach, Johann Christoph Friedrich (German composer)
    longest surviving son of J.S. and Anna Magdalena Bach....
  • Bach, Johann Sebastian (German composer)
    composer of the Baroque era, the most celebrated member of a large family of northern German musicians. Although he was admired by his contemporaries primarily as an outstanding harpsichordist, organist, and expert on organ building, Bach is now generally regarded as one of the greatest composers of all time and is celebrated as the creator of the Brandenburg Concertos...
  • Bach Long Vi (island, Vietnam)
    island of northern Vietnam in the Gulf of Tonkin, halfway between the mouth of the Red River (Song Hong) near Nam Dinh and the Chinese island of Hainan. The island is a plateau that rises abruptly to 190 ft (58 m) above sea level and is fringed with precipitous cliffs. Fishing resources are abundant in the surrounding gulf of the South China Sea....
  • Bach trumpet (musical instrument)
    Instruments in keys other than B♭ are frequently used. The “piccolo” trumpet in D, also known as the Bach trumpet, was invented in about 1890 by the Belgian instrument-maker Victor Mahillon for use in the high trumpet parts of music by J.S. Bach and George Frideric Handel. Other forms include the older E♭ trumpet, the trumpet in C, piccolo trumpets in F and high B...
  • Bach, Wilhelm Friedemann (German composer)
    eldest son of J.S. and Maria Barbara Bach, composer during the period of transition between Baroque and Rococo styles....
  • Bach-Gesellschaft (music society)
    ...by a crowd of enthusiastic pupils, among whom were Joseph Joachim, Hans von Bülow, Arthur Sullivan, and Frederic Hymen Cowen. In 1850, with Otto Jahn and Robert Schumann, Hauptmann founded the Bach-Gesellschaft (“Bach Society”); for the remainder of his life he served as the society’s president and edited the first three volumes of the Bach-Gesellschaft (BG) edition ...
  • Bach-Institute (music society)
    ...Its chief publication is its research journal, the Bach-Jahrbuch (from 1904). By 1950 the deficiencies of the BG edition had become painfully obvious, and the Bach-Institut was founded, with headquarters at Göttingen and Leipzig, to produce a new standard edition (the Neue Bach-Ausgabe, or NBA), a publication that eventually exceeded 100......
  • Bach-Werke-Verzeichnis (work by Schmieder)
    ...Prelude and Fugue in G Minor (before 1707, BWV 535a). (The “BWV” numbers provided are the standard catalog numbers of Bach’s works as established in the Bach-Werke-Verzeichnis, prepared by the German musicologist Wolfgang Schmieder.)...
  • Bach-y-Rita, Paul (American neurobiologist)
    ...research in neuroplasticity was carried out in the 1960s, when scientists attempted to develop machines that interface with the brain in order to help blind people. In 1969 American neurobiologist Paul Bach-y-Rita and several of his colleagues published a short article titled Vision substitution by tactile image projection, which detailed the workings of such a......
  • bacha nagma (dance)
    ...(devotional music of the Muslim mystics known as Ṣūfīs) was banned in the 1920s by the ruling maharaja, who felt this dance was becoming too sensual. It was replaced by the bacha nagma, performed by young boys dressed like women. A popular entertainment at parties and festivals, it is also customarily included in modern stage plays....
  • Bacha Saqqao (Tajik leader)
    ...proposals that caused his popular support to drop and enraged the mullahs (Muslim religious leaders). In 1928 a tribal revolt resulted in a chaotic situation during which a notorious bandit leader, Bacheh Saqqāw (Bacheh-ye Saqqā; “Child of a Water Carrier”), seized Kabul, the capital city, and declared himself ruler. Amānollāh attempted to regain the th...
  • Bachan (island, Indonesia)
    island, North Maluku propinsi (province), Indonesia. One of the northern Moluccas, in the Molucca Sea, it lies just southwest of the large island of Halmahera. The islands of Kasiruta to the northwest, Mandioli to the west, and about 80 other islets compose the Bacan Island group. With an area of about 700 square miles (1,800 square km), B...
  • Bacharach, Burt (American composer, songwriter, and pianist)
    ...Conrad Hall for Butch Cassidy and the Sundance KidArt Direction: Herman Blumenthal, John DeCuir and, Jack Martin Smith for Hello, Dolly!Original Score for a Motion Picture: Burt Bacharach for Butch Cassidy and the Sundance KidScore of a Musical Picture Original or Adaptation: Lennie Hayton and Lionel Newman for Hello, Dolly!Song Original for the Picture:......
  • Bachchan, Aishwarya (Indian actress)
    Indian actress whose classic beauty made her one of Bollywood’s premier stars....
  • Bachchan, Amitabh (Indian actor)
    Indian film actor, perhaps the most popular star in the history of that nation’s cinema, known primarily for his roles in action films....
  • Bachchan, Harivansh Rai (Indian poet)
    Indian poet (b. Nov. 27, 1907, Allahabad, United Provinces [now Uttar Pradesh], India—d. Jan. 18, 2003, Mumbai [Bombay], Maharashtra, India), was one of the most acclaimed Hindi-language poets of the 20th century. His long lyric poem Madhushala (The House of Wine), published in 1935, brought him legions of fans. Bachchan’s public readings were attended by thousands of p...
  • Bachcheh Saqow (Tajik leader)
    ...proposals that caused his popular support to drop and enraged the mullahs (Muslim religious leaders). In 1928 a tribal revolt resulted in a chaotic situation during which a notorious bandit leader, Bacheh Saqqāw (Bacheh-ye Saqqā; “Child of a Water Carrier”), seized Kabul, the capital city, and declared himself ruler. Amānollāh attempted to regain the th...
  • Bacheh Saqqāw (Tajik leader)
    ...proposals that caused his popular support to drop and enraged the mullahs (Muslim religious leaders). In 1928 a tribal revolt resulted in a chaotic situation during which a notorious bandit leader, Bacheh Saqqāw (Bacheh-ye Saqqā; “Child of a Water Carrier”), seized Kabul, the capital city, and declared himself ruler. Amānollāh attempted to regain the th...
  • Bachelard, Gaston (French writer)
    ...thinkers who were also superb stylists and who deemed it a function of philosophy to understand the aesthetic phenomenon: Henri Bergson (1859–1941), Paul Valéry (1871–1945), and Gaston Bachelard (1884–1962). No more poetical advocate of reverie arose in the 20th century than La Poétique de la rêverie (1960; The Poetics of Reverie) and the....
  • Bachelard, Suzanne (French philosopher)
    Suzanne Bachelard, who in 1957 translated Husserl’s Formale und transzendentale Logik: Versuch einer Kritik der logischen Vernunft, has pointed to the significance of Husserl for modern logic; and Jacques Derrida, an original French thinker on the limits of thought and language, has combined Phenomenology and Structuralism in his interpretation of literature....
  • Bachelet Jeria, Verónica Michelle (president of Chile)
    Chilean politician, president of Chile (2006– ). She was the first woman president of Chile and the first popularly elected South American woman president whose political career was established independent of her husband....
  • Bachelet, Michelle (president of Chile)
    Chilean politician, president of Chile (2006– ). She was the first woman president of Chile and the first popularly elected South American woman president whose political career was established independent of her husband....
  • Bachelier, Louis (French scientist)
    The most important stochastic process is the Brownian motion or Wiener process. It was first discussed by Louis Bachelier (1900), who was interested in modeling fluctuations in prices in financial markets, and by Albert Einstein (1905), who gave a mathematical model for the irregular motion of colloidal particles first observed by the Scottish botanist Robert Brown in 1827. The first......
  • Bacheller, Irving (American writer)
    journalist and novelist whose books, generally set in upper New York State, are humorous and full of penetrating character delineations, especially of rural types....
  • Bacheller, Irving Addison (American writer)
    journalist and novelist whose books, generally set in upper New York State, are humorous and full of penetrating character delineations, especially of rural types....
  • bachelor (degree)
    ...certifications that they had attained the guild status of a “master.” There was originally only one degree in European higher education, that of master or doctor. The baccalaureate, or bachelor’s degree, was originally simply a stage toward mastership and was awarded to a candidate who had studied the prescribed texts in the trivium (grammar, rhetoric, and logic) for three ...
  • Bachelor and the Bobbysoxer, The (film by Reis [1947])
    Screenplay: George Seaton for Miracle on 34th StreetOriginal Story: Valentine Davies for Miracle on 34th StreetOriginal Screenplay: Sidney Sheldon for The Bachelor and the BobbysoxerCinematography, Black-and-White: Guy Green for Great ExpectationsCinematography, Color: Jack Cardiff for Black NarcissusArt Direction, Black-and-White: John Bryan for Great......
  • Bachelor, Charles (American mechanic)
    ...laboratory and machine shop in the rural environs of Menlo Park, N.J.—12 miles south of Newark—where he moved in March 1876. Accompanying him were two key associates, Charles Batchelor and John Kruesi. Batchelor, born in Manchester in 1845, was a master mechanic and draftsman who complemented Edison perfectly and served as his “ears” on such projects......
  • Bachelor of Arts (degree)
    ...four years. The master’s degree involves one to two years’ additional study, while the doctorate usually involves a lengthier period of work. British and American universities customarily grant the bachelor’s as the first degree in arts or sciences. After one or two more years of coursework, the second degree, M.A. or M.S., may be obtained by examination or the completion o...
  • Bachelor of Science (degree)
    ...are now awarded in the United States, for example, with the largest number in science, technology, engineering, medicine, and education. The commonest degrees, however, are still the B.A. and the B.S., to which the signature of a special field may be added (e.g., B.S.Pharm., or Bachelor of Science in Pharmacy). These special fields have their corresponding designations at the graduate......
  • Bachelor, The (play by Turgenev)
    Simultaneously, he tried his hand at writing plays, some, like A Poor Gentleman (1848), rather obviously imitative of the Russian master Nikolay Gogol. Of these, The Bachelor (1849) was the only one staged at this time, the others falling afoul of the official censors. Others of a more intimately penetrating character, such as One May Spin a Thread Too Finely (1848), led to......
  • bachelordom (degree)
    ...certifications that they had attained the guild status of a “master.” There was originally only one degree in European higher education, that of master or doctor. The baccalaureate, or bachelor’s degree, was originally simply a stage toward mastership and was awarded to a candidate who had studied the prescribed texts in the trivium (grammar, rhetoric, and logic) for three ...
  • bachelor’s button (plant)
    The genus includes a wide variety of annual and perennial garden plants such as the cornflower, or bachelor’s button (C. cyanus), and the basket-flower (C. americana). Others are variously known as knapweed, thornless thistle, cardo-del-valle, dusty miller, blue bottle, mountain bluet, sweet-sultan, hard heads, and Spanish buttons....
  • Bachelors, Community of (English group)
    ...were to be local men, appointed for one year. The households of the king and queen were to be reformed. The drafting of further measures took time. In October 1259 a group calling itself the Community of Bachelors, which seems to have claimed to represent the lesser vassals and knights, petitioned for the fulfillment of the promises of the magnates and king to remedy its grievances. As a......
  • bachelor’s degree (degree)
    ...certifications that they had attained the guild status of a “master.” There was originally only one degree in European higher education, that of master or doctor. The baccalaureate, or bachelor’s degree, was originally simply a stage toward mastership and was awarded to a candidate who had studied the prescribed texts in the trivium (grammar, rhetoric, and logic) for three ...
  • Bachet de Méziriac, Claude-Gaspar (French mathematician)
    ...produced books devoted solely to recreational problems not only in mathematics but frequently in mechanics and natural philosophy as well. The first important contribution was that of the Frenchman Claude-Gaspar Bachet de Méziriac, one of the earliest pioneers in this field, who is remembered for two mathematical works: his Diophanti, the first edition of a Greek text on the......
  • Bachiacca (Italian artist)
    Cartoons were designed by such leading Mannerist artists of Florence as Jacopo Pontormo (1494–1556/57), Francesco Salviati (1510–63), Il Bronzino (1503–72), and Bachiacca (1494–1557), who designed the “Grotesques” (c. 1550; Uffizi, Florence), one of the most famous and influential tapestry sets produced by the Arrazeria Medicea....
  • Bachianas brasileiras (work by Villa-Lobos)
    As mentioned above, Villa-Lobos’s works are characterized by a singular blend of Western classical music and Brazilian folk songs and rhythms. One of his best-known works is Bachianas brasileiras (written 1930–44), a set of nine pieces for various instrumental and vocal groups, in which a contrapuntal technique in the manner of Bach is applied to themes ...
  • Bachman, Hannah (American reformer)
    American social worker who launched a successful campaign to establish municipal, state, and national boards and associations for child welfare....
  • Bachman, John (American naturalist and minister)
    naturalist and Lutheran minister who helped write the text of works on North American birds and mammals by renowned naturalist and artist John James Audubon....
  • Bachmann, Ingeborg (Austrian author)
    Austrian author whose sombre, surreal writings often deal with women in failed love relationships, the nature of art and humanity, and the inadequacy of language....
  • Bachofen, Johann Jakob (Swiss jurist and anthropologist)
    Swiss jurist and early anthropological writer whose book Das Mutterrecht (1861; “Mother Right”) is regarded as a major contribution to the development of modern social anthropology....
  • Bachur, Elijah (Italian grammarian)
    German-born Jewish grammarian whose writings and teaching furthered the study of Hebrew in European Christendom at a time of widespread hostility toward the Jews....
  • baci (Lao ritual)
    The ethnic Lao ritual of the baci, in which strings are tied around a person’s wrist to preserve good luck, has indeed been elevated in Laos to the place of a national custom. The baci is associated with transitions, namely, giving birth, getting married, entering the monkhood, going away, returning, beginning a new year, and welcoming or biddin...
  • Baciccia (Italian painter)
    leading Roman Baroque painter of the second half of the 17th century....
  • Baciccio (Italian painter)
    leading Roman Baroque painter of the second half of the 17th century....
  • Bacílek, Karol (Slovak statesman)
    ...In 1960 he agreed to the rehabilitation of the Slovaks purged in the 1950s. The new constitution, however, restricted Slovak autonomy further. By 1963, new leaders had moved into power in Slovakia; Karol Bacílek, who was compromised by the purges in the 1950s, was replaced as first secretary of the party in Slovakia by Alexander Dubček. When the rehabilitated Slovaks, among whom.....
  • Bacillariophyceae (algae)
    class of fuccous algae, commonly known as diatoms, in the division Chromophyta. See diatom....
  • Bacillariophyta (protist phylum)
    class of fuccous algae, commonly known as diatoms, in the division Chromophyta. See diatom.......
  • bacillary dysentery (intestinal disorder)
    infection of the gastrointestinal tract by bacteria of the genus Shigella. The illness produces cramplike abdominal pain as well as diarrhea consisting of either watery stools or scant stools containing mucus and blood....
  • Bacille Calmette-Guérin vaccine (medicine)
    vaccine against tuberculosis. The BCG vaccine is prepared from a weakened strain of Mycobacterium bovis, a bacteria closely related to M. tuberculosis, which causes the disease. The vaccine was developed over a period of 13 years, from 1908 to 1921, by French bacteriologists Albert Calmette...
  • bacilli (bacteria)
    (genus Bacillus), any of a group of rod-shaped, gram-positive, aerobic or (under some conditions) anaerobic bacteria widely found in soil and water. The term bacillus in a general sense has been applied to all cylindrical or rodlike bacteria. The largest species are about 2 μm (micrometres; 1 μm = 10−6 m) across by 7 μm long and f...
  • bacillite (geology)
    in geology, a type of crystallite....
  • bacillus (bacterial shape)
    Individual bacteria can assume one of three basic shapes: spherical (coccus), rodlike (bacillus), or curved (vibrio, spirillum, or spirochete). Considerable variation is seen in the actual shapes of bacteria, and cells can be stretched or compressed in one dimension. Bacteria that do not separate from one another after cell division form characteristic clusters that are helpful in their......
  • bacillus (bacteria)
    (genus Bacillus), any of a group of rod-shaped, gram-positive, aerobic or (under some conditions) anaerobic bacteria widely found in soil and water. The term bacillus in a general sense has been applied to all cylindrical or rodlike bacteria. The largest species are about 2 μm (micrometres; 1 μm = 10−6 m) across by 7 μm long and f...
  • Bacillus (bacteria)
    (genus Bacillus), any of a group of rod-shaped, gram-positive, aerobic or (under some conditions) anaerobic bacteria widely found in soil and water. The term bacillus in a general sense has been applied to all cylindrical or rodlike bacteria. The largest species are about 2 μm (micrometres; 1 μm = 10−6 m) across by 7 μm long and f...
  • Bacillus alvie (bacterium)
    European foulbrood is caused by a nonsporeforming bacterium, Streptococcus pluton, but Bacillus alvie and Acromobacter eurydice are often associated with Streptococcus pluton. This disease is similar in appearance to American foulbrood. In some instances it severely affects the colonies, but they recover so that colony destruction is not necessary. Terramycin can......
  • Bacillus anthracis (bacterium)
    acute, infectious, febrile disease of animals and humans caused by Bacillus anthracis, a bacterium that under certain conditions forms highly resistant spores capable of persisting and retaining their virulence for many years. Although anthrax most commonly affects grazing animals such as cattle, sheep, goats, horses, and mules, humans can develop the disease by eating the meat......
  • Bacillus Calmette-Guérin vaccine (medicine)
    vaccine against tuberculosis. The BCG vaccine is prepared from a weakened strain of Mycobacterium bovis, a bacteria closely related to M. tuberculosis, which causes the disease. The vaccine was developed over a period of 13 years, from 1908 to 1921, by French bacteriologists Albert Calmette...
  • Bacillus cereus (bacterium)
    Bacillus cereus sometimes causes spoilage in canned foods and food poisoning of short duration. B. subtilis, also widely disseminated, is a common contaminant of laboratory cultures (it plagued Louis Pasteur in many of his experiments) and is often found on human skin. Most strains of Bacillus are not pathogenic for humans and only infect them incidentally in their role as......
  • Bacillus fusiformis (bacterium)
    acute and painful infection of the tooth margins and gums that is caused by the symbiotic microorganisms Bacillus fusiformis and Borrelia vincentii. The chief symptoms are painful, swollen, bleeding gums; small, painful ulcers covering the gums and tooth margins; and characteristic fetid breath. The ulcers may spread to the throat and tonsils. Fever and malaise may also be......
  • Bacillus larvae (bacterium)
    American foulbrood, caused by a spore-forming bacterium, Bacillus larvae, is the most serious brood disease. It occurs throughout the world wherever bees are kept and affects workers, drones, and queens. The spores are highly resistant to heat and chemicals. A comb containing brood severely infected with this disease has a mottled appearance caused by the mixture of healthy capped brood......
  • Bacillus mesentericus (bacterium)
    Bacteria associated with bread spoilage include Bacillus mesentericus, responsible for “ropy” bread, and the less common but more spectacular Micrococcus prodigiosus, causative agent of “bleeding bread.” Neither ropy bread nor bleeding bread is particularly toxic. Enzymes secreted by B. mesentericus change the starch inside the loaf into a gummy......
  • Bacillus pestis (bacterium)
    infectious fever caused by the bacillus Yersinia pestis, a bacterium transmitted from rodents to humans by the bite of infected fleas. Plague was the cause of some of the most devastating epidemics in history. It was the disease behind the Black Death of the 14th century, when as much as one-third of Europe’s population died. Huge pandemics also arose in Asia i...
  • Bacillus polymyxa (bacterium)
    ...thuringiensis insecticides are harmless to vertebrates but effective against pests of agricultural products. Medically useful antibiotics are produced by B. subtilis (bacitracin) and B. polymyxa (polymyxin B)....
  • Bacillus popilliae (bacterium)
    ...to prey on the larvae—have been imported into the United States, where some of them have become established. Of even greater promise as a biological control is a disease-inducing bacterium, Bacillus popilliae, which causes milky disease in larvae; its use has reduced Japanese beetle infestations in some areas....
  • Bacillus subtilis (bacterium)
    Bacillus cereus sometimes causes spoilage in canned foods and food poisoning of short duration. B. subtilis, also widely disseminated, is a common contaminant of laboratory cultures (it plagued Louis Pasteur in many of his experiments) and is often found on human skin. Most strains of Bacillus are not pathogenic for humans and only infect them incidentally in their role as......
  • Bacillus thuringiensis (bacterium)
    ...for humans and only infect them incidentally in their role as soil organisms; a notable exception is B. anthracis, which causes anthrax (q.v.) in humans and domestic animals. B. thuringiensis causes disease in insects; B. thuringiensis insecticides are harmless to vertebrates but effective against pests of agricultural products. Medically useful antibiotics are......
  • bacitracin (drug)
    ...It has excellent activity against Pseudomonas aeruginosa and Enterobacteriaceae. Aztreonam has a low incidence of toxicity, but it must be administered parenterally. Bacitracin is produced by a special strain of Bacillus subtilis. Because of its severe toxicity to kidney cells, its use is limited to the topical treatment of skin......
  • back (rugby)
    It was not until the early 1880s that specialized positions began to appear, particularly among the backs, with Allen Rotherham of Oxford and England establishing the position of halfback, named for a player who took up a position between the scrum and the rest of the backs. Fullbacks, who took the farthest position from the scrum, were also common, and by this time three additional players......
  • back (lute)
    In the lute the part of the resonating chamber over which the strings pass is called the belly, and the other side of the resonator is called the back. The portion between the back and belly is the side, or rib. A lute may be plucked with the fingers or a plectrum or may be bowed, but the means of sound production do not affect the essential morphological identity of plucked, struck, and bowed......
  • Back Bay (area, Boston, Massachusetts, United States)
    ...of land along the line of present-day Washington Street. To the west of the neck were great reaches of mudflats and salt marshes that were covered by water at high tide and known collectively as the Back Bay. The Charles River flowed through the Back Bay to Boston Harbor and separated the peninsula from the mainland to the north and west. To the east, Town Cove indented Boston’s harbour ...
  • Back Bay (bay, Bombay, India)
    ...open sea. The western ridge terminates at Malabār Hill, 180 feet (55 metres) above sea level, which is one of the highest points in Bombay. Between the two ridges lies the shallow expanse of Back Bay. On a slightly raised strip of land between the head of Back Bay and the harbour is the fort, the original nucleus around which the city grew; it is now chiefly occupied by public and......
  • Back Bay (region, Virginia, United States)
    ...extends 28 miles (45 km) southward from the mouth of Chesapeake Bay to the North Carolina border, covering 302 square miles (782 square km) of land and water, with 28 miles (45 km) of ocean front. Back Bay is a brackish lagoon and a national wildlife refuge that occupies about 39 square miles (101 square km) and parallels the ocean at the south end of the city. Founded in 1887, Virginia Beach.....
  • back bonding
    ...The second mode of interaction with the metal is the simultaneous back-donation of electron density from the metal to the carbonyl ligand, which is called back π bonding....
  • “back door to war” theory (World War II analysis)
    Was there a “back door” to World War II, as some revisionist historians have asserted? According to this view, President Franklin D. Roosevelt, inhibited by the American public’s opposition to direct U.S. involvement in the fighting and determined to save Great Britain from a Nazi victory in Europe, manipulated events in the Pacific in order to provoke a Japanese attack on the...
  • back emf (physics)
    ...the increase of a current than the same coil with an air core. The iron core increases the inductance; for the same rate of change of the current in the coil, a greater opposing electromotive force (back emf) is present to choke the current....
  • Back for the First Time (album by Ludacris)
    ...word of mouth the album managed to enter the Billboard 200 chart, and Ludacris was soon signed to the record label Def Jam South, which repackaged Incognegro as Back for the First Time (2000). That major label debut ultimately reached number four in the Billboard 200....
  • “Back from the U.S.S.R.” (work by Gide)
    ...him that he had found a faith in Communism. In 1936 he set out on a visit to the Soviet Union, but later expressed his disillusionment with the Soviet system in Retour de l’U.R.S.S. (1936; Return from the U.S.S.R.) and Retouches à mon retour de l’U.R.S.S. (1937; Afterthoughts on the U.S.S.R.)....
  • back furrow (agriculture)
    ...is plowed across the field; on the return trip, a furrow slice is lapped over the first slice. This leaves a slightly higher ridge than the second, third, and other slices. The ridge is called a back furrow. When two strips of land are finished, the last furrows cut leave a trench about twice the width of one bottom, called a dead furrow. When land is broken by continuous lapping of furrows,......
  • back junction layer (engineering)
    The three energy-conversion layers below the antireflection layer are the top junction layer, the absorber layer, which constitutes the core of the device, and the back junction layer. Two additional electrical contact layers are needed to carry the electric current out to an external load and back into the cell, thus completing an electric circuit. The electrical contact layer on the face of......
  • Back, Kurt W. (American sociologist)
    ...to be closed down and fumigated because of reports of toxic insect bites—reports that could not subsequently be substantiated. The U.S. sociologist Alan C. Kerckhoff and the U.S. psychologist Kurt W. Back found that the crisis came after a period during which the women employees had performed unusual amounts of overtime work. The women who became ill from the mysterious insect bites had....
  • back mutation (genetics)
    ...against which to compare a mutant allele. Mutation can occur in two directions; mutation from wild type to mutant is called a forward mutation, and mutation from mutant to wild type is called a back mutation or reversion....
  • Back of the Yards Council (community group, Chicago, Illinois, United States)
    ...and criminology, Alinsky worked as a criminologist in Illinois for eight years. In 1938, he undertook his first community organizing campaign in a working-class area of Chicago; the result was the Back of the Yards Council, which became a prototype for a generation of community organizations. In 1940, Alinsky founded the Industrial Areas Foundation and trained cadres of organizers in his......
  • back pain (pathology)
    ...and criminology, Alinsky worked as a criminologist in Illinois for eight years. In 1938, he undertook his first community organizing campaign in a working-class area of Chicago; the result was the Back of the Yards Council, which became a prototype for a generation of community organizations. In 1940, Alinsky founded the Industrial Areas Foundation and trained cadres of organizers in his.........
  • back pi bonding
    ...The second mode of interaction with the metal is the simultaneous back-donation of electron density from the metal to the carbonyl ligand, which is called back π bonding....
  • back projection (photography)
    ...viewing angle increases). They are therefore especially suitable for screenings in small rooms—e.g., for home movies. The glass-beaded screen is made up of many tiny beads on a canvas backing, the lenticular screen of tiny, uniformly spaced, cylindrical lenses....
  • Back, Sir George (British explorer)
    naval officer who helped to trace the Arctic coastline of North America. He twice accompanied the British explorer John Franklin to Canada’s Northwest Territories (1819–22 and 1825–27) and later conducted two expeditions of his own to the same region....
  • back stroke (cricket)
    ...stroke, in which the batsman advances his front leg to the pitch (direction) of the ball and plays it in front of the wicket (if played with aggressive intent, this stroke becomes the drive); back stroke, in which the batsman moves his rear leg back before playing the ball; leg glance (or glide), in which the ball is deflected behind the wicket on the leg side; cut, in which the batsman......
  • back swimmer (insect)
    any of about 200 species of insects (order Heteroptera) that occur worldwide and are named for their ability to swim on their backs, which are shaped like the keel and sides of a boat. The back swimmer uses its long, oarlike legs for propulsion and has an oval-shaped head and an elongated body, generally less than 15 mm (0.6 inch) in length. It is a good example of countershading, as its light-col...
  • Back to Methuselah (work by Shaw)
    ...war’s bloodshed. Attempting to keep from falling into “the bottomless pit of an utterly discouraging pessimism,” Shaw wrote five linked plays under the collective title Back to Methuselah (1922). They expound his philosophy of creative evolution in an extended dramatic parable that progresses through time from the Garden of Eden to ad ...
  • back vowel (linguistics)
    ...part of the tongue pushed forward in the mouth and somewhat arched. The a in “had,” the e in “bed,” and the i in “fit” are front vowels. A back vowel—e.g., the u in “rule” and the o in “pole”—is produced with the back part of the tongue raised toward the soft palate (vel...
  • back-arc basin (geology)
    Where both converging plates are oceanic, the margin of the older oceanic crust will be subducted because older oceanic crust is colder and therefore more dense. As the dense slab collapses into the asthenosphere, however, it also may “roll back” oceanward and cause extension in the overlying plate. This results in a process known as back-arc spreading, in which a basin opens up......
  • back-formation (linguistics)
    Back-formations and blends are becoming increasingly popular. Back-formation is the reverse of affixation, being the analogical creation of a new word from an existing word falsely assumed to be its derivative. For example, the verb “to edit” has been formed from the noun “editor” on the reverse analogy of the noun “actor” from “to act,” and....
  • back-propagation algorithm (computing)
    Two modifications of this simple feedforward neural network account for the growth of commercial applications. First, a network can be equipped with a feedback mechanism, known as a back-propagation algorithm, that enables it to adjust the connection weights back through the network, training it in response to representative examples. Second, recurrent neural networks can be developed,......
  • back-strap loom (weaving instrument)
    ...known of the American Indian weavers, have used the simple two-bar vertical loom for several centuries to produce their beautiful rugs and blankets. A form of the horizontal two-bar loom was the back-strap loom, in which one bar was tied to a tree or other stationary device, the second being attached to the weaver’s waist by a strap. The weaver could control the tension of the warp yarns...
  • backache
    ...known of the American Indian weavers, have used the simple two-bar vertical loom for several centuries to produce their beautiful rugs and blankets. A form of the horizontal two-bar loom was the back-strap loom, in which one bar was tied to a tree or other stationary device, the second being attached to the weaver’s waist by a strap. The weaver could control the tension of the warp yarns...
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