124 résultats pour "loss"

• Eye. I INTRODUCTION Eye, light-sensitive organ of vision in animals. The eyes of

  Several structures, not parts of the eyeball, contribute to the protection of the eye. The most important of these are the eyelids, two folds of skin and tissue, upper andlower, that can be closed by means of muscles to form a protective covering over the eyeball against excessive light and mechanical injury. The eyelashes, a fringe ofshort hairs growing on the edge of either eyelid, act as a screen to keep dust particles and insects out of the eyes when the eyelids are partly closed. Inside the...

• W. L. Mackenzie King. I INTRODUCTION W. L. Mackenzie King (1874-1950), tenth prime

  V SECOND TERM AS PRIME MINISTER By the election of 1925 most of the rifts in the Liberal Party were healed. Little had been achieved by King's government except for some tariff reduction and thereorganization of Canadian railroads, but no mistakes had been made. The real issue of the election was the personalities of the party leaders, King and the brilliant butarrogant Conservative, Arthur Meighen. The Conservatives swept English-speaking Canada, and they won 116 seats. The Liberals won 101, a...

• Hurricane.

  V HOW HURRICANES ARE DETECTED AND MONITORED Since 1943 U.S. military and civilian aircraft have been flying into hurricanes to measure wind velocities and directions, the location and size of the eye, air pressures,and temperatures in different parts of the storm. A coordinated system of tracking hurricanes was developed in the mid-1950s, and steady improvements have beenmade over the years. In addition to reports from aircraft, geosynchronous weather satellites (since 1966) and ocean buoys tha...

• Poliomyelitis.

  Physical therapy helps patients with paralytic polio stretch and move affected muscles. This movement minimizes the atrophy, or shrinkage, of affected muscles andlimbs and builds strength. Exercises can also retrain working muscles to compensate for other muscles that have permanently lost the ability to move. Rehabilitativetherapy trains patients to use braces, crutches, and other devices that provide support and aid mobility. V PREVENTION OF POLIO Immunization with polio vaccine is the best w...

• Radioactivity I INTRODUCTION Marie Curie Working with her husband, Pierre Curie, French physicist Marie Curie discovered the radioactive elements polonium and radium in 1898.

  Rutherford when he allowed an alpha-emitting substance to decay near an evacuated thin-glass vessel. The alpha particles were able to penetrate the glass and werethen trapped in the vessel, and within a few days the presence of elemental helium was demonstrated by use of a spectroscope. Beta particles were subsequentlyshown to be electrons, and gamma rays to consist of electromagnetic radiation of the same nature as X rays but of considerably greater energy. A The Nuclear Hypothesis Rutherford...

• Indo-Pakistani Wars - History.

  wrest Jammu and Kashmīr from India through the use of force. This effort failed as India held its ground, and the war ended in a stalemate after almost two months ofarmed conflict. Although the second war over the territory was shorter than the first, the increased firepower of the two nations resulted in a more deadly war, with atotal of about 6,800 battle casualties. A Events Before the War A number of factors precipitated the second conflict over Jammu and Kashm īr. In the wake of a border w...

• French and Indian War.

  Virginia as well as the French governor-general of Canada had attempted to seize their lands. After receiving large presents of supplies and arms, the Iroquoisgrudgingly renewed their alliances with the British colonies. Delegates then moved on to plan other defensive measures. An important topic was a plan of union developed by Benjamin Franklin. The Albany Plan, as it became known, proposed a single institution to govern all of the Britishcolonies in America. Under the plan, each colony would...

• French and Indian War - Canadian History.

  Virginia as well as the French governor-general of Canada had attempted to seize their lands. After receiving large presents of supplies and arms, the Iroquoisgrudgingly renewed their alliances with the British colonies. Delegates then moved on to plan other defensive measures. An important topic was a plan of union developed by Benjamin Franklin. The Albany Plan, as it became known, proposed a single institution to govern all of the Britishcolonies in America. Under the plan, each colony would...

• Republican Party.

  the reaction to the depression that the Republican Party controlled Congress for only 4 of the 48 years between 1932 and 1980. The Republicans did win the presidencyfour times during that period—in 1952, 1956, 1968, and 1972—when the Democratic Party split or when some unusual combination of circumstances occurred. Fromthe 1930s through the 1970s, however, the Democratic Party was the dominant party in the United States. The response of the Republicans to this new situation was confusion, anger,...

• Space Shuttle - astronomy.

  The two SRBs, with their combined thrust of some 26 million newtons (about 5.8 million lb), provide most of the power for the first two minutes of flight. The SRBs takethe space shuttle to an altitude of 45 km (28 mi) and a speed of 4,973 km/h (3,094 mph) before they separate and fall back into the ocean to be retrieved,refurbished, and prepared for another flight. After the boosters fall away, the three main engines continue to provide thrust. These engines are clustered at the rear end of the...

• Drug. I INTRODUCTION Drug, substance that affects the function of living cells, used

  normalizing chemical activity in the emotional centers of the brain. Antianxiety drugs, also referred to as tranquilizers, treat anxiety by decreasing the activity in theanxiety centers of the brain. Sedative-hypnotic drugs are used both as sedatives to reduce anxiety and as hypnotics to induce sleep. Sedative-hypnotic drugs act by reducing brain-cell activity.Stimulant drugs, on the other hand, increase neuronal (nerve cell) activity and reduce fatigue and appetite. Analgesic drugs reduce pain...

• Chess.

  There are two standard methods of recording chess moves: the algebraic system and the descriptive system. In both systems, the pieces are designated by capitalinitials: K for king, Q for queen, R for rook, B for bishop, and N for knight. The initial P for pawn is used in the descriptive system only. Castling is noted as either 0-0(“short” castling on the king’s side) or 0-0-0 (“long” castling on the queen’s side). Each square is part of both a file and a rank, and in the algebraic system, that u...

• Plant - biology.

  B1 Vacuoles Vacuoles are membrane-bound cavities filled with cell sap, which is made up mostly of water containing various dissolved sugars, salts, and other chemicals. B2 Plastids Plastids are types of organelles, structures that carry out specialized functions in the cell. Three kinds of plastids are important here. Chloroplasts contain chlorophyllsand carotenoid pigments; they are the site of photosynthesis, the process in which light energy from the sun is fixed as chemical energy in the b...

• Glacier.

  covered. In spring the snow cover begins to melt in the lower reaches, exposing the ice surface. As temperatures increase, the melting moves up the glacier. Thesnowline is the highest position the melting reaches during the year. Firn is old granular snow. The firn limit may not exactly coincide with the annual snowline since insome years rapid melting leaves behind firn patches below the snowline. Some glaciers exhibit features called ice streams and icefalls. Ice streams are valley glaciers th...

• Bacteria - biology.

  A2 b Bacterial Killers Some dramatic infectious diseases result from exposure to bacteria that are not part of our normal bacterial community. Cholera, one of the world’s deadliest diseasestoday, is caused by the bacterium Vibrio cholerae . Cholera is spread in water and food contaminated with the bacteria, and by people who have the disease. After entering the body, the cholera bacteria grow in the intestines, often along the surface of the intestinal wall, where they secrete a toxin (poiso...

• Amphibian (animal) - biology.

  strong enough to kill potential predators. C Hearing, Vision, and Vocalizations Amphibians rely on their senses to find food and evade predators. Amphibians lack external ears but have well-developed internal ears. Hearing is most acute in frogs,which typically have a middle ear cavity for transferring sound vibrations from the eardrum, or tympanum, to the inner ear. Frogs and toads also use their keen hearingin communicating with one another. Using a true voice box, or larynx, and a large, exp...

• Medical Ethics.

  medical profession. In recent years, however, the field of medical ethics has struggled to keep pace with the many complex issues raised by new technologies for creating and sustaininglife. Artificial-respiration devices, kidney dialysis, and other machines can keep patients alive who previously would have succumbed to their illnesses or injuries.Advances in organ transplantation have brought new hope to those afflicted with diseased organs. New techniques have enabled prospective parents to con...

• Labor Unions in the United States - U.

  National Guard troops were used against the strikers, with the result that the strike was lost and the union that conducted it virtually destroyed. In 1894 a strike by theAmerican Railway Union against the Pullman Palace Car Company was defeated by an injunction issued under the Sherman Antitrust Act of 1890, which made acombination or contract in restraint of trade illegal. Thereafter employers used injunctions with increasing frequency and effectiveness as an antistrike weapon. See also Hours...

• Colonialism and Colonies.

  by plundering the riches of existing civilizations in the Americas and by seizing the area’s mineral wealth through mining. These practices were promoted by the policy of mercantilism that many European colonial powers adopted. Those who advocated mercantilism believed that exports toforeign countries were preferable both to trade within a country and to imports because exports brought more money into the country. They also believed that thewealth of a nation depended primarily on the possession...

• Colonialism and Colonies .

  by plundering the riches of existing civilizations in the Americas and by seizing the area’s mineral wealth through mining. These practices were promoted by the policy of mercantilism that many European colonial powers adopted. Those who advocated mercantilism believed that exports toforeign countries were preferable both to trade within a country and to imports because exports brought more money into the country. They also believed that thewealth of a nation depended primarily on the possession...

• European Union .

  safeguard the interests of the member states, a common assembly with advisory authority only, and a court of justice to settle disputes. D European Economic Community (EEC) In 1957 the participants in the ECSC signed two more treaties, known as the Treaties of Rome. These treaties created the European Atomic Energy Community(Euratom) for the development of peaceful uses of atomic energy and, most important, the European Economic Community (EEC, often referred to as the CommonMarket). The EEC tr...

• Guatemala - country.

  C Climate The climate of Guatemala varies according to elevation, from hot coastal plains to cold mountain heights. Most of the population lives between 900 and 2,400 m (3,000and 8,000 ft) above sea level, where there are warm days and cool nights with average annual temperatures of 20°C (68°F). The coastal regions are hot and humid,with average annual temperatures of 28°C (83°F). A rainy season, from May through October, is sometimes called “winter” because it brings cloudy afternoons andlower...

• Minnesota - geography.

  C Climate Minnesota’s climate is classified as humid continental because normally there is a sufficient amount of precipitation to provide at least some surplus for runoff, andbecause Minnesota’s temperature conditions are largely controlled by its location in the interior of the large landmass of North America. The result is extreme seasonaltemperature variations. The average January temperature is about -18°C (about 0°F) in the northwest and about -10°C (about 14°F) in the south, but thetherm...

• Minnesota - USA History.

  C Climate Minnesota’s climate is classified as humid continental because normally there is a sufficient amount of precipitation to provide at least some surplus for runoff, andbecause Minnesota’s temperature conditions are largely controlled by its location in the interior of the large landmass of North America. The result is extreme seasonaltemperature variations. The average January temperature is about -18°C (about 0°F) in the northwest and about -10°C (about 14°F) in the south, but thetherm...

• George Bush.

  1986 it was folded into Harken Energy Corporation, another Texas petroleum company. Bush served as a consultant and a member of Harken’s board of directors. In 1987 Bush relocated his family to Washington, D.C., to assist his father in his bid to become president. He worked as a campaign adviser at his father’s nationalcampaign headquarters, serving as a liaison to the media and to conservative and Christian leaders. He was a trusted confidant of his father and mother, whosometimes dispatched Bu...

• George Bush - USA History.

  1986 it was folded into Harken Energy Corporation, another Texas petroleum company. Bush served as a consultant and a member of Harken’s board of directors. In 1987 Bush relocated his family to Washington, D.C., to assist his father in his bid to become president. He worked as a campaign adviser at his father’s nationalcampaign headquarters, serving as a liaison to the media and to conservative and Christian leaders. He was a trusted confidant of his father and mother, whosometimes dispatched Bu...

• Kansas - geography.

  at the adjoining cities of Kansas City, Kansas, and Kansas City, Missouri. Its chief headstreams are the Republican and Smoky Hill rivers, which join to form the KansasRiver at Junction City. Each of the headstreams has numerous tributaries. The Kansas River proper is only 270 km (170 mi) long, but the Smoky Hill River has a lengthof 870 km (540 mi), and the Republican River has a length of 720 km (450 mi). The main tributary flowing into the Kansas River is the Big Blue River. The Arkansas Rive...

• Kansas - USA History.

  at the adjoining cities of Kansas City, Kansas, and Kansas City, Missouri. Its chief headstreams are the Republican and Smoky Hill rivers, which join to form the KansasRiver at Junction City. Each of the headstreams has numerous tributaries. The Kansas River proper is only 270 km (170 mi) long, but the Smoky Hill River has a lengthof 870 km (540 mi), and the Republican River has a length of 720 km (450 mi). The main tributary flowing into the Kansas River is the Big Blue River. The Arkansas Rive...

• Brazil Wins Third World Cup In Soccer.

  Playing their fifth consecutive game at Guadalajara's Jalisco Stadium, the Brazilians faced Uruguay in the semifinals on June 17. Uruguay struck first, capitalizingon a blunder by goalie Felix (Miéli Venerand Felix). Brazil equalized just before the half when midfielder Clodoaldo (Tavares Santana Clodoaldo) took a pass fromTostao and drove it home. It was all Brazil in the second half. Pelé constructed two late-game scores within 13 minutes, feeding Jairzinho and then Rivelino. The 3-1victory av...

• Flood Control.

  When scientific research into the causes of floods showed that the construction of levees was insufficient as a method of control, the first steps were made to provide forreforestation and soil conservation. The Clarke-McNary Act of 1924, the Mississippi Flood Control Act of 1928, and the McSweeney-McNary Act of 1928 were all directedtoward that end. In 1935 the Soil Conservation Service was established by the Congress of the United States under an act declaring a policy of permanent provision f...

• American Civil War.

  free state to keep the balance in the Senate. It also provided that slavery would be excluded from the still unorganized part of the Louisiana Territory. A line was drawnfrom Missouri’s southern boundary, at the latitude of 36°30’, and slavery would not be allowed in the territory north of that line,with the exception of Missouri. B Compromise of 1850 Agitation against slavery continued in the North. The South reacted by defending it ever more strongly. The Mexican War, by which the United Stat...

• American Civil War - U.

  free state to keep the balance in the Senate. It also provided that slavery would be excluded from the still unorganized part of the Louisiana Territory. A line was drawnfrom Missouri’s southern boundary, at the latitude of 36°30’, and slavery would not be allowed in the territory north of that line,with the exception of Missouri. B Compromise of 1850 Agitation against slavery continued in the North. The South reacted by defending it ever more strongly. The Mexican War, by which the United Stat...

• Owl - biology.

  Among the largest species of typical owls are the eagle owls. They have tufts of feathers on their heads that are called “ears.” The great horned owl is the only eagleowl found in the Americas. It is about 60 cm (25 in) in length with a wingspan of 1.4 m (60 in). Numerous species of eagle owls inhabit Europe, Africa, and Asia. Mostwidely distributed is the northern eagle owl, found from Scandinavia and Spain to Japan. It is about 71 cm (28 in) long with a wingspan of about 2m (72 in). Nearly asl...

• Excerpt from Little Dorrit - anthology.

  'That,' said the turnkey, 'is agen her.' 'She is so little used to go out alone,' said the debtor, 'that I am at a loss to think how she will ever make her way here, if she walks.' 'P'raps,' quoth the turnkey, 'she'll take a ackney coach.' 'Perhaps.' The irresolute fingers went to the trembling lip. 'I hope she will. She may not think of it.' 'Or p'raps,' said the turnkey, offering his suggestions from the top of his well-worn wooden stool, as he might have offered them to a...

• Alzheimer's Disease.

  compared residents of Ibadan, Nigeria, who eat a mostly low-fat vegetarian diet, with African Americans living in Indianapolis, Indiana, whose diet included a variety ofhigh-fat foods. The Nigerians were less likely to develop Alzheimer’s disease compared to their U.S. counterparts. Some researchers suspect that health problems suchas high blood pressure, atherosclerosis (arteries clogged by fatty deposits), high cholesterol levels, or other cardiovascular problems may play a role in the devel...

• Exercise.

  broad, and most studies suggest a positive relationship between physical fitness and mental achievement. The relationship between regular aerobic exercise and cardiovascular health and longevity is well established. Regular exercise leads to a reduction in the risk ofcoronary heart disease, in which fatty deposits (plaque) form in blood vessels supplying the muscular wall of the heart, compromising oxygen delivery to the heartmuscle. In addition, with regular exercise the efficiency of the heart...

• Giant Panda - biology.

  In 2007 conservationists announced that a parasitic roundworm was responsible for a significant number of the panda deaths reported in the wild since 1990. Theparasite Baylisascaris schroederi causes the disease visceral larval migrans, which results in bleeding in the lungs, the liver, and the intestines, and can also affect the brain. It is not known if other recent pandas deaths were caused by the same parasite or by a different contagious disease. Loss of habitat from deforestation is forc...

• Zebra - biology.

  C Life Span Captive zebras have lived into their late 30s. Life expectancy in the wild, where predators abound, is probably not much more than 12 years. IV SOCIAL BEHAVIOR Like horses, zebras have large brains and a wide variety of social behaviors. Although they cannot match the overall intelligence of mammals that hunt, zebras interactwith each other in complex ways. Zebras usually live in groups known as herds, but the social structure of these groups depends on the species. The plains zeb...

• Zachary Taylor.

  army fled back across the Río Grande into Mexico. When Polk got word of the victories, he promoted Taylor to major general. Congress awarded him two gold medals. B1 Battle of Monterrey In September 1846, Taylor began an invasion of northern Mexico. His army of 6000 consisted of regulars and volunteers. On September 21 he attacked the fortifiedcity of Monterrey, which was defended by more than 7000 Mexicans under General Pedro de Ampudia. Taylor divided his army, giving Brigadier General William...

• Zachary Taylor

  army fled back across the Río Grande into Mexico. When Polk got word of the victories, he promoted Taylor to major general. Congress awarded him two gold medals. B1 Battle of Monterrey In September 1846, Taylor began an invasion of northern Mexico. His army of 6000 consisted of regulars and volunteers. On September 21 he attacked the fortifiedcity of Monterrey, which was defended by more than 7000 Mexicans under General Pedro de Ampudia. Taylor divided his army, giving Brigadier General William...

• Koala - biology.

  V REPRODUCTION Female koalas become sexually mature around 18 to 24 months of age. They can produce one offspring a year until they reach about 13 years of age. Males begin toproduce sperm around age 2 and, in the absence of older, stronger males, they may breed at that young age. More often, however, a male must grow big enough tocompete with other males for females, and mating generally begins for males at about 4 years of age. The breeding season for koalas is from October to May, during the...

• Ecology.

  an input of nutrients exceeding the capability of the ecosystem to process them. Nutrients eroded and leached from agricultural lands, along with sewage and industrialwastes accumulated from urban areas, all drain into streams, rivers, lakes, and estuaries. These pollutants destroy plants and animals that cannot tolerate theirpresence or the changed environmental conditions caused by them; at the same time they favor a few organisms more tolerant to changed conditions. Thus,precipitation filled...

• Ecology - biology.

  an input of nutrients exceeding the capability of the ecosystem to process them. Nutrients eroded and leached from agricultural lands, along with sewage and industrialwastes accumulated from urban areas, all drain into streams, rivers, lakes, and estuaries. These pollutants destroy plants and animals that cannot tolerate theirpresence or the changed environmental conditions caused by them; at the same time they favor a few organisms more tolerant to changed conditions. Thus,precipitation filled...

• Benito Mussolini.

  Mussolini threatened to order his tens of thousands of armed Black Shirts to occupy Rome if he were not asked to form the new government. Bands of Fascists beganmoving towards the capital in what would become known as the March on Rome. King Victor Emmanuel III at first leaned towards declaring a state of emergency andsending the army against the Fascists, but powerful interest groups, state officials, and army leaders convinced him that Mussolini should be given the chance to endwhat they consi...

• Benito Mussolini .

  Mussolini threatened to order his tens of thousands of armed Black Shirts to occupy Rome if he were not asked to form the new government. Bands of Fascists beganmoving towards the capital in what would become known as the March on Rome. King Victor Emmanuel III at first leaned towards declaring a state of emergency andsending the army against the Fascists, but powerful interest groups, state officials, and army leaders convinced him that Mussolini should be given the chance to endwhat they consi...

• Jimmy Carter.

  B Election of 1976 Carter apparently decided as early as 1972, halfway through his four-year term as governor, that he would seek the presidency of the United States. Soon after the1972 election, his campaign manager drew up a detailed campaign strategy. Carter followed the plan closely, beginning an exhausting schedule of campaigning as soonas his gubernatorial term ended. When Carter formally announced in January 1975 that he was a candidate for president, he had almost no national reputation...

• Jimmy Carter

  B Election of 1976 Carter apparently decided as early as 1972, halfway through his four-year term as governor, that he would seek the presidency of the United States. Soon after the1972 election, his campaign manager drew up a detailed campaign strategy. Carter followed the plan closely, beginning an exhausting schedule of campaigning as soonas his gubernatorial term ended. When Carter formally announced in January 1975 that he was a candidate for president, he had almost no national reputation...

• Parkinson Disease.

  III SYMPTOMS Parkinson disease most notably affects motor control (muscle activity). The disease progresses differently for each individual—symptoms develop swiftly in some peopleand slowly in others. Some Parkinson patients may develop problems that affect their intellect or ability to reason, or they may suffer from depression or anxiety. A Motor Control Problems Doctors look for the presence of four principal symptoms in patients they suspect may have Parkinson disease. Tremor (the involun...

• Persian Gulf War.

  to “use all necessary means” to force Iraq from Kuwait if Iraq remained in the country after January 15, 1991. The Iraqis rejected the ultimatum. Soon after the vote,the United States agreed to a direct meeting between Secretary of State James Baker and Iraq’s foreign minister. The two sides met on January 9. Neither offered tocompromise. The United States underscored the ultimatum, and the Iraqis refused to comply with it, even threatening to attack Israel. For the United States, themeeting was...

• Persian Gulf War - History.

  to “use all necessary means” to force Iraq from Kuwait if Iraq remained in the country after January 15, 1991. The Iraqis rejected the ultimatum. Soon after the vote,the United States agreed to a direct meeting between Secretary of State James Baker and Iraq’s foreign minister. The two sides met on January 9. Neither offered tocompromise. The United States underscored the ultimatum, and the Iraqis refused to comply with it, even threatening to attack Israel. For the United States, themeeting was...