795 résultats pour "botha"

• Learning.

  B1 Acquisition The acquisition phase is the initial learning of the conditioned response—for example, the dog learning to salivate at the sound of the bell. Several factors can affect the speed of conditioning during the acquisition phase. The most important factors are the order and timing of the stimuli. Conditioning occurs most quickly when theconditioned stimulus (the bell) precedes the unconditioned stimulus (the food) by about half a second. Conditioning takes longer and the response is...

• Global Warming.

  some of the warming influence of increasing greenhouse gases. A1 Carbon Dioxide Carbon dioxide is the second most abundant greenhouse gas, after water vapor. Carbon dioxide constantly circulates in the environment through a variety of naturalprocesses known as the carbon cycle. It is released into the atmosphere from natural processes such as eruptions of volcanoes; the respiration of animals, whichbreathe in oxygen and exhale carbon dioxide; and the burning or decay of plants and other organic...

• Uganda - country.

  Uganda’s population is predominantly rural and is concentrated in the south, particularly in the crescent at the edge of Lake Victoria and in the southwest. Almost allUgandans are black Africans. Foreign residents make up less than 4 percent of the population and come mostly from neighboring states. In 2008 Uganda’s population was estimated at 31,367,972. The estimated growth rate of the population in 2008 was 3.6 percent. The birth rate was 48 per 1,000people and the death rate 12 per 1,000. Th...

• South America - Geography.

  South America is dominated by relatively warm climatic regimes. Spanning nearly the entire continent along the equator is a belt of humid tropical climate that grades tothe north and south into broad zones where the length of the rainy season and the amount of rainfall diminish. These zones have wet summers and dry winters and aresubject to prolonged droughts. Droughts are a particularly serious problem in northeastern Brazil and along the northern coast of Venezuela and Colombia. The areas ofra...

• Comparative Anatomy.

  In comparing two species, anatomists have to be careful to differentiate between homologous structures, which are ones that have evolved from a shared ancestor, andanalogous structures, which have developed from different origins. Homologous structures are built on the same underlying plan. A human arm, a bat’s wing, and awhale’s flipper look quite different from the outside, but the bones inside reveal that these limbs all have the same basic structure. Analogous structures, by contrast,often l...

• Modern Dance I INTRODUCTION Modern Dance, tradition of theatrical dance unique to the 20th century.

  Though both had their own interests and styles, their collaboration helped establish modern dance as a 20th-century artform. Shawn helped overcome prejudices against men in the new field of modern dance.E.O. Hoppé/Corbis Because a dance language involves elements such as posture, use of the body’s weight, and the character of movements (sinuous, angular, and so forth)—as well asspecific movements of the head, torso, hands, arms, legs, and feet—most creators of modern dance have considered it ess...

• Vice President of the United States.

  naval operations. Located in northwest Washington at Massachusetts Avenue and 34th Street, the three-story Queen Anne-style house is within easy driving distance ofCapitol Hill and the White House. The vice president receives an annual salary of $189,300. The vice president has a staff and offices in the Everett M. Dirksen Senate Office Building, near the Capitol, toassist with legislative matters, as well as a personal office near the Senate lobby. The vice president also has staff and offices...

• Islamic Art and Architecture I INTRODUCTION Córdoba Mosque Courtyard This mosque and courtyard with its repeated horseshoe arches was built between the 8th and 10th centuries in Córdoba, Spain.

  Süleymaniye MosqueThe Süleymaniye Mosque in İstanbul was built in 1550. The architect, Sinan, based his design on Byzantine churches, inparticular the Hagia Sophia. The large central dome above a square opens to smaller spaces vaulted by buttressing half-domes. The four tapering minarets with balconies are characteristic of the architectural style of later Islamic mosques.Gian Berto Vanni/Art Resource, NY The few and relatively simple rituals of the Islamic faith gave rise to a unique religious...

• Stock Exchange.

  A Example of a Trade In an example of a trade, an investor wanting to buy 200 shares—also known as two round lots, of 100 shares each—of IBM stock will telephone or e-mail the order to abrokerage firm. This communication is normally made to an individual called a stockbroker. The investor might desire to buy the shares at the market, or current, price.On the other hand, the investor may choose to pay no more than a set amount per share. The brokerage firm then contacts one of its floor brokers...

• Public Education in the United States.

  opportunities for them to break out from whatever social or economic circumstances constrained their development. IV HIGHER EDUCATION During the 20th century participation in higher or postsecondary education in the United States increased as dramatically as it did in American high schools. At thebeginning of the century about 2 percent of Americans from the ages of 18 to 24 were enrolled in a college. There were fewer than 1,000 colleges then, with enrollmenttotaling about 157,000 students. N...

• New France - Canadian History.

  the colony now consisted of a governor-general, an intendant , and a Sovereign Council, all located at Québec, with local governors at Trois-Rivières and Montréal, and law courts for all three districts. The senior official was the governor-general, responsible for military matters and for relations with the indigenous nations and theEnglish colonies. The intendant, a noble trained in law, was the official responsible for civil affairs: justice, law enforcement, and the maintenance of the colon...

• Metalwork I INTRODUCTION Metalwork, in the fine arts, objects of artistic, decorative, and utilitarian value made of one or more kinds of metal--from precious to base--fashioned by either casting, hammering, or joining or a combination of these techniques.

  Early Bronze DiskThis disk with the head of Acheloos, an Etruscan river god, was made of bronze, an alloy of copper and tin, sometime inthe early 5th century bc. It comes from the necropolis of Monte Quaglieri in Tarquinia. Alloys are made by smelting twodifferent metals together.Scala/Art Resource, NY Knowledge of smelting ultimately led to knowledge of mixing different ores together in the smelting process to produce simple alloys. This followed an intermediateperiod, about 3000 BC, when comp...

• James Monroe.

  In October 1786, Monroe resigned from Congress and settled with his bride in Fredericksburg, Virginia, where he began a law practice. His retirement from politics wasbrief. He was soon elected to the town council, and then once again to the Virginia legislature. However, Monroe never lost touch with national politics. He corresponded regularly with both Jefferson and Madison. In 1786 Monroe attended the AnnapolisConvention, which had been called to consider interstate commerce and other matters...

• James Monroe - USA History.

  In October 1786, Monroe resigned from Congress and settled with his bride in Fredericksburg, Virginia, where he began a law practice. His retirement from politics wasbrief. He was soon elected to the town council, and then once again to the Virginia legislature. However, Monroe never lost touch with national politics. He corresponded regularly with both Jefferson and Madison. In 1786 Monroe attended the AnnapolisConvention, which had been called to consider interstate commerce and other matters...

• Whale - biology.

  III BEHAVIOR OF WHALES Studies of whales in captivity have taught scientists much about the complex social behavior of whales. Since the late 1980s, advances in the use of satellite trackingsystems have also broadened opportunities for scientists to observe how whales behave in the wild. A Swimming and Diving Whales swim by making powerful up-and-down movements of the tail flukes, which provide thrust. The power comes from body muscles that flex the lower spine upand down in a wavelike motion...

• Ottoman Empire .

  fleets at Suez, Egypt; though the Portuguese were not expelled, Selim did manage to prevent the establishment of a total Portuguese monopoly over the spice trade. Selim I died in 1520 after having spent most of his short reign on matters pertaining to the east. His son and successor Süleyman I (reigned 1520-1566) again turnedthe attention of the Ottomans to the west. In August 1521 Süleyman, later known as Süleyman the Magnificent, opened the road to Hungary by capturing Belgrade, aHungarian str...

• Ottoman Empire - History.

  fleets at Suez, Egypt; though the Portuguese were not expelled, Selim did manage to prevent the establishment of a total Portuguese monopoly over the spice trade. Selim I died in 1520 after having spent most of his short reign on matters pertaining to the east. His son and successor Süleyman I (reigned 1520-1566) again turnedthe attention of the Ottomans to the west. In August 1521 Süleyman, later known as Süleyman the Magnificent, opened the road to Hungary by capturing Belgrade, aHungarian str...

• Johann Sebastian Bach.

  from his duties, and even tossed him into jail for “too obstinately requesting his dismissal.” But after several weeks the duke saw it was of no use and let him go. E Köthen: 1717-1723 Bach’s new employer, Leopold, loved and understood music and could play the violin, viola da gamba, and harpsichord as well as sing bass. The prince held Bach in highregard and stood as godfather for his seventh child. Bach, in turn, named the child Leopold August in his employer’s honor. Bach later said that the...

• Ukraine - country.

  a major hazard, especially to Ukraine’s water supply. The Chernobyl’ complex was finally shut down completely in December 2000, with the financial assistance ofWestern nations. The funds were to pay for the completion of two other nuclear power plants that would produce enough power to make up for the loss of the powersupply from the Chernobyl’ plant. III PEOPLE OF UKRAINE The population of Ukraine was estimated in 2008 at 45,994,287, giving the country a population density of 76 persons per s...

• Child Development.

  developmental scientists have studied how cultural values guide the skills and attitudes that children acquire as they mature, and how brain maturation influences thedevelopment of thinking and feeling. For a more detailed discussion of child development theories, see the Theories of Child Development section of this article. III BASIC QUESTIONS A Nature and Nurture Scholars have long debated the relative importance of nature (hereditary influences) and nurture (environmental influences) i...

• Hungary - country.

  Northern Hungary lacks sufficient water, especially between July and October, when precipitation levels are typically low. Canals irrigate the Great Hungarian Plain,which is subject to drought. Because of the country’s mainly flat terrain, only limited water resources can be harnessed for hydroelectric power. F Environmental Issues Rapid industrialization in Hungary following World War II contributed significantly to a number of major environmental problems, including air, water, and soil pollu...

• Race - biology.

  distributed as a cline, generally varying along a north-south line. Skin color is lightest in northern Europeans, especially in those who live around the Baltic Sea, andbecomes gradually darker as one moves toward southern Europe, the Mediterranean, the Middle East, and into northern Africa and northern subtropical Africa. Skin isdarkest in people who live in the tropical regions of Africa. The lack of clear-cut discontinuities makes any racial boundary based on skin color totally arbitrary. Sim...

• From Bulfinch's Mythology: Minerva (Athena) - anthology.

  Spenser tells the story of Arachne in his 'Muiopotmos,' adhering very closely to his master Ovid, but improving upon him in the conclusion of the story. The twostanzas which follow tell what was done after the goddess had depicted her creation of the olive tree: 'Amongst these leaves she made a Butterfly, With excellent device and wondrous slight,Fluttering among the olives wantonly,That seemed to live, so like it was in sight;The velvet nap which on his wings doth lie,The silken down with whic...

• Killer Whale - biology.

  V REPRODUCTION Mating occurs more often among killer whales of different pods to avoid inbreeding within pods. About 16 to 18 months after mating, females give birth to a single calf.Newborn calves weigh about 200 kg (440 lb) and are about 2.5 m (8 ft) long. Mothers nurse their calf for 14 to 18 months, although mothers continue to be protectiveof their young long after the offspring have been weaned. Scientists do not know how long killer whales live in the wild. Scientists estimate that male...

• In-Line Skating.

  the foot using a combination of laces and buckles. Many skaters prefer a simple closure system that has laces on the lower portion of the skate and a buckle at the top.The boot liner is made of a soft, padded, cloth portion that fits inside the outer shell. Boot liners should be vented, which keeps the feet cool by allowing perspiration toescape during strenuous workouts or long trips. Attached to the bottom of each skate is the wheel frame. The frame houses from three to five wheels. The wheels...

• Wetland.

  Other plants and animals have special adaptations suited for living in a wet environment. Most emergent plants have air spaces in their stems that enable oxygen to betransported to roots that grow in sediments with no oxygen. Some of the trees that grow in swamps form a set of roots above the soil surface or above the water thatallows them to get oxygen to the lower roots. In saltwater wetlands, specialized cells can limit the amount of salt that enters a plant, or specialized organs can excrete...

• Jane Austen.

  years later.) Mansfield Park is Jane Austen’s most ambitious novel—in length, in variety of characterization, and in the scope of its theme. It centers on the effects of upbringing on personal morality in three families—the middle-class Bertrams, the fashionable Crawfords, and the impoverished Prices. Austen has been praised for her presentation ofthe complex relations between the members of the families, but as in Sense and Sensibility, she frustrates the expectations of her readers that the...

• Jane Austen I INTRODUCTION Jane Austen English author Jane Austen crafted satirical romances set within the confines of upper-middle-class English society.

  up their personal pride and prejudices before they can enter into a happy relationship together. As do Austen’s earlier writings, Pride and Prejudice displays the themes of appearance versus reality, and impulse versus deliberation. Elizabeth, trusting her own impulses, makes a mistake about Darcy and his apparent arrogance that deliberation and further experience eventually cause her to correct. Of Elizabeth, Austenwrote: “I must confess that I think her as delightful a creature as ever appea...

• Classification - biology.

  species based on the fewest number of shared changes that have occurred from generation to generation. IV HISTORY OF CLASSIFICATION SYSTEMS Classification is one of the oldest sciences, but despite its age it is still a vigorous field full of new discoveries and methods. Much like other fields of science, greatthinkers have shaped the course of classification. One of the earliest classification schemes was established by Greek philosopher Aristotle, who lived in the 300s BC. Aristotle believe...

• Comedy

  Socrates suffered in the comedy of Aristophanes. Throughout history, opposition to comedy and laughter has been strongest in societies which emphasize physical restraint, decorum and conformity. Many medieval monastic orders had statutes forbidding laughter. The Puritan and Victorian eras saw many condemnations of comedy and laughter. The more authoritarian the regime, the greater its suppression of comedy. Hitler even set up ‘joke courts' to punish those who made fun of his regime - one Berl...

• 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...

• Elizabeth I I INTRODUCTION Elizabeth I (1533-1603), queen of England and Ireland (1558-1603), daughter of Henry VIII and his second wife, Anne Boleyn.

  Catholic challenges and plots persisted through much of Elizabeth’s reign, and Elizabeth reacted to them strongly. In 1569 a group of powerful Catholic nobles innorthern England rose in rebellion but were savagely repressed. The northern earls were executed, their property and those of their followers was confiscated, and theirheirs were deprived of their inheritance. In 1570 the pope excommunicated Elizabeth, sanctioning Catholic efforts to dethrone her. In 1571 an international conspiracywas u...

• Elizabeth I.

  Catholic challenges and plots persisted through much of Elizabeth’s reign, and Elizabeth reacted to them strongly. In 1569 a group of powerful Catholic nobles innorthern England rose in rebellion but were savagely repressed. The northern earls were executed, their property and those of their followers was confiscated, and theirheirs were deprived of their inheritance. In 1570 the pope excommunicated Elizabeth, sanctioning Catholic efforts to dethrone her. In 1571 an international conspiracywas u...

• Elizabeth I .

  Catholic challenges and plots persisted through much of Elizabeth’s reign, and Elizabeth reacted to them strongly. In 1569 a group of powerful Catholic nobles innorthern England rose in rebellion but were savagely repressed. The northern earls were executed, their property and those of their followers was confiscated, and theirheirs were deprived of their inheritance. In 1570 the pope excommunicated Elizabeth, sanctioning Catholic efforts to dethrone her. In 1571 an international conspiracywas u...

• Grover Cleveland.

  Americans, Roman Catholics, and Southerners, who all generally supported the Democratic Party. The statement lost Blaine any chance of getting the Irish Americanvote in New York City. The Mugwumps supported Cleveland because of Blaine’s political past. Even the Prohibition Party candidate received 25,000 votes that normallywould have gone to the Republican candidate. New York’s 36 electoral votes swung the election to Cleveland. He won the state’s vote by only about 1000 in a total vote of more...

• Grover Cleveland

  Americans, Roman Catholics, and Southerners, who all generally supported the Democratic Party. The statement lost Blaine any chance of getting the Irish Americanvote in New York City. The Mugwumps supported Cleveland because of Blaine’s political past. Even the Prohibition Party candidate received 25,000 votes that normallywould have gone to the Republican candidate. New York’s 36 electoral votes swung the election to Cleveland. He won the state’s vote by only about 1000 in a total vote of more...

• Rhythm-and-Blues Music I INTRODUCTION Tina Turner American singer Tina Turner began performing rhythm-and-blues music in a band led by her former husband, Ike Turner, in the 1960s.

  thousands of black Americans migrated from the rural South to Midwest, Northeast, and West Coast cities. In popular music, new styles were created to meet thechanging tastes of this demographic group, leading to the development of the urbane sounds of R&B. The profound sociological changes of the World War II period were accompanied by two significant technological developments: the invention of the electric guitar in thelate 1930s and the discovery of the German-invented tape recorder by the mu...

• Nicaraguan Revolution.

  Directorate. Within a year Robelo and Violeta Chamorro left the junta, and the Council of State was reorganized to guarantee an overwhelming Sandinista majority.Elections were postponed, restrictions were placed on the media, and relations with the Roman Catholic Church became increasingly tense. Two non-Sandinistasreplaced Robelo and Chamorro on the junta, but they had little power, and the government’s relations with opposition political parties and the private business sectordeteriorated. A D...

• Country Music I INTRODUCTION Willie Nelson Country singer and musician Willie Nelson gained national popularity during the 1970s for a string of country hits, including the 1978 hits "Mammas Don't Let Your Babies Grow Up to Be Cowboys" and "Georgia On My Mind.

  Singer and mandolin player Bill Monroe is known as the father of bluegrass music. A virtuoso mandolin player, Monroe combined traditional folk ballads and gospel songswith string-band music played at very fast tempos. Monroe, with his band The Blue Grass Boys, performed from the mid-1920s until Monroe’s death in 1996. Otherwell-known bluegrass performers include banjo player Earl Scruggs, who played with Monroe during the 1940s; the Osborne Brothers, a duo from Kentucky known forits work during...

• Asia - geography.

  the Himalayas, the world’s highest mountain system. The Pacific Ocean plate drifted westward, scraping along the Eurasian plate and slipping under its coastal edge. This created the islands of Japan, Taiwan, the Kurils, theRyūky ūs, and the Philippines. Southeast Asia lies at the intersection of the Eurasian, Pacific Ocean, and Indian Ocean plates. Over time the contact between these platescreated the mountain ranges of mainland Southeast Asia. The continued slow movement of the plates causes fr...

• Asia - history.

  the Himalayas, the world’s highest mountain system. The Pacific Ocean plate drifted westward, scraping along the Eurasian plate and slipping under its coastal edge. This created the islands of Japan, Taiwan, the Kurils, theRyūky ūs, and the Philippines. Southeast Asia lies at the intersection of the Eurasian, Pacific Ocean, and Indian Ocean plates. Over time the contact between these platescreated the mountain ranges of mainland Southeast Asia. The continued slow movement of the plates causes fr...

• Animal Behavior - biology.

  The first motor program analyzed in much detail was the egg-rolling response of geese. When a goose sees an egg outside its nest, it stares at the egg, stretches itsneck until its bill is just on the other side of the egg, and then gently rolls the egg back into the nest. At first glance this seems a thoughtful and intelligent piece ofbehavior, but it is a mechanical motor program; almost any smooth, rounded object (the sign stimulus) will release the response. Furthermore, removal of the egg on...

• George Herbert Walker Bush.

  Lebanon. More troubling was the disclosure that agents operating under direct White House supervision used profits from the arms sales to buy weapons for thecontras, a group of anti-government Nicaraguan rebels, despite an explicit congressional ban on such aid. Bush later claimed that he opposed the arms-for-hostagesdeal, but offered little evidence to back his claims ( see Iran-Contra Affair). C 1988 Presidential Election While the Reagan-Bush program helped produce prosperity for the wealth...

• George Herbert Walker Bush - USA History.

  Lebanon. More troubling was the disclosure that agents operating under direct White House supervision used profits from the arms sales to buy weapons for thecontras, a group of anti-government Nicaraguan rebels, despite an explicit congressional ban on such aid. Bush later claimed that he opposed the arms-for-hostagesdeal, but offered little evidence to back his claims ( see Iran-Contra Affair). C 1988 Presidential Election While the Reagan-Bush program helped produce prosperity for the wealth...

• Excerpt from Barnaby Rudge - anthology.

  Mr. Dennis rolled lazily over upon his breast, and resting his chin upon his hand in imitation of the attitude in which Hugh lay, said, as he too looked towards thedoor: “ Ay, ay, you knew him, brother, you knew him. But who'd suppose to look at that chap now, that he could be the man he is! Isn't it a thousand cruel pities, brother,that instead of taking his nat'ral rest and qualifying himself for further exertions in this here honourable cause, he should be playing at soldiers like a boy?...

• From Pride and Prejudice - anthology.

  But why Mr Darcy same so often to the Parsonage, it was more difficult to understand. It could not be for society, as he frequently sat there ten minutes togetherwithout opening his lips; and when he did speak, it seemed the effect of necessity rather than of choice—a sacrifice to propriety, not a pleasure to himself. He seldomappeared really animated. Mrs Collins knew not what to make of him. Colonel Fitzwilliam's occasionally laughing at his stupidity, proved that he was generallydifferent, wh...

• Jean Chrétien.

  In 1969, when Chrétien introduced policy proposals based on this principle, indigenous peoples reacted with such hostility that he ultimately had to withdraw theproposals. Despite this and other clashes with indigenous leaders, Chrétien continued to work at improving the government relations with them. By the time he left theDepartment of Indian and Northern Affairs in 1974, he had earned their respect and appreciation for his efforts. Following the 1974 election, Trudeau appointed Chrétien pres...

• Jean Chrétien - Canadian History.

  In 1969, when Chrétien introduced policy proposals based on this principle, indigenous peoples reacted with such hostility that he ultimately had to withdraw theproposals. Despite this and other clashes with indigenous leaders, Chrétien continued to work at improving the government relations with them. By the time he left theDepartment of Indian and Northern Affairs in 1974, he had earned their respect and appreciation for his efforts. Following the 1974 election, Trudeau appointed Chrétien pres...

• Tajikistan - country.

  by more than 100 percent due to a high birth rate and improvements in medical care. During the early 1990s, however, the growth rate began to decline due to civilwar and emigration. A Ethnic Groups and Languages Tajiks constitute the largest ethnic group in Tajikistan, making up about 65 percent of the population. The peoples who live in Gorno-Badakhshan, located in the Pamirs,are classified as Tajiks, although their languages and customs are distinct. The largest minority group in the country...