131 résultats pour "able"

• Vikings .

  Wessex (England) and Charles II the Bald and Louis III in France could command their resources to move to fortify their towns, station fleets and naval patrols alongthe coasts, and organize localized and mobile military forces. Some Christian leaders paid ransom to the larger Viking armies of the 10th and early 11th centuries.Taxing their people to pay the “danegeld,” the tribute to the Vikings, became a regular defensive strategy. But in return for the cash, the Vikings often negotiatedpeaceful...

• Army. I INTRODUCTION Army, military land forces of a nation, assembled, drilled, disciplined,

  disappearance for several centuries of large standing armies in Europe. A Middle Ages Feudalism was based on a concept of local defense, each baron or landowner governing land that had been given him by the king, and each lord having his ownpersonal protective forces recruited from among men who worked for him. In return, each lord and his men were pledged to annual service to the monarch and couldbe called on in special instances, as in the defense of Christendom during the Crusades. National...

• 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...

• Genetic Engineering.

  Pseudomonas fluorescens bacterium. The genetically altered Pseudomonas fluorescens bacterium produces light in proportion to the amount of its activity in breaking down the naphthalene, thus providing a way to monitor the efficiency of the process ( see Bioremediation). A3 Medicine In 1982 the United States Food and Drug Administration (FDA) approved for the first time the medical use of a recombinant DNA protein, the hormone insulin, whichhad been cloned in large quantities by inserting th...

• 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...

• 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...

• Observatory - astronomy.

  Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...

• Extrasolar Planets - astronomy.

  When a planet passes in a front of the star it orbits—an event called a transit—it causes a small dip in the brightness of the star. Measuring the slight change in thebrightness can be used not only to directly detect a planet, but to determine its size and orbit. However, the planet needs to orbit in a plane that lies in a telescope’sline of sight on the star. Despite long odds, Earth-based telescopes have detected and studied a few exoplanets using this method. The first space telescope design...

• Soil. I INTRODUCTION Soil, the loose material that covers the land surfaces of

  an exchange between plants and the atmosphere, as oxygen diffuses into the soil and is used by roots for respiration. In turn, the resulting carbon dioxide diffusesthrough pore spaces and returns to the atmosphere. This exchange is most efficient in soils with a high degree of porosity. For farmers, gardeners, landscapers, andothers with a professional interest in soil health, the process of aeration—making holes in the soil surface to permit the exchange of air—is a crucial activity. Theburrowi...

• The way in which companies frame themselves, their products and their clients

• 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,...

• Winston Churchill I INTRODUCTION Winston Churchill (1874-1965), British politician and prime minister of the United Kingdom (1940-1945, 1951-1955), widely regarded as the greatest British leader of the 20th century.

  sufficient tools to break the stalemate on the western front and he worked on developing armored fighting vehicles (tanks) to break the deadlock and end theslaughter. As the lines hardened on the western front, Churchill focused on a campaign to force open the Dardanelles Strait, controlled by the Ottoman Empire, to give the Allies adirect route to Russia through the Black Sea. Such a move would bring much-needed supplies to the Russian armies and eliminate the Ottomans from the war. Whenthe nav...

• Winston Churchill.

  sufficient tools to break the stalemate on the western front and he worked on developing armored fighting vehicles (tanks) to break the deadlock and end theslaughter. As the lines hardened on the western front, Churchill focused on a campaign to force open the Dardanelles Strait, controlled by the Ottoman Empire, to give the Allies adirect route to Russia through the Black Sea. Such a move would bring much-needed supplies to the Russian armies and eliminate the Ottomans from the war. Whenthe nav...

• Winston Churchill .

  sufficient tools to break the stalemate on the western front and he worked on developing armored fighting vehicles (tanks) to break the deadlock and end theslaughter. As the lines hardened on the western front, Churchill focused on a campaign to force open the Dardanelles Strait, controlled by the Ottoman Empire, to give the Allies adirect route to Russia through the Black Sea. Such a move would bring much-needed supplies to the Russian armies and eliminate the Ottomans from the war. Whenthe nav...

• Horse - biology.

  Horses reach sexual maturity at about one and a half years. The estrous cycle in the mare—a mature female horse—typically lasts 21 days. During the first five days ofthe cycle, the mare is usually receptive to mating. The estrous cycle stops during winter and resumes in the spring, which is the start of the breeding season. Astallion—a mature male horse—approaching a mare in estrus engages in various courtship rituals. These include uttering nickering sounds and sniffing and licking themare’s ge...

• Mexican War.

  men, mostly Mexicans, rode to Nacogdoches to capture the rebellious Fredonians. The small garrison of Fredonians soundly defeated their attackers in the only battle ofthe rebellion. When Mexican troops arrived at Nacogdoches a short time later, the republic had been dissolved and the leader of the colonists had fled to Louisiana. B The Texas Revolution Although the Fredonians were not successful, by the 1830s the population of Mexican Texas included many immigrants from the United States. These...

• Slavery in the United States - U.

  tripled, from about 1.2 million to almost 4 million in 1860. The natural growth of the slave population meant that slavery could survive without new slave imports. Natural population growth also hastened the transition from an African to an African American slave population. By the 1770s, only about 20 percent of slaves in thecolonies were African-born, although the concentration of Africans remained higher in South Carolina and Georgia. After 1808 the proportion of African-born slavesbecame tin...

• Ethiopia - country.

  constitute about 6 percent of the population. The Somali, who live in the east and southeast, notably in the Ogadēn region, are about equal in number to the Shangalla.The Denakil inhabit the semidesert plains east of the highlands. The nonindigenous population includes Yemenis, Indians, Armenians, and Greeks. B Political Divisions Ethiopia is divided into nine regions composed of specific ethnic groups. The regions, which have a significant degree of autonomy, are Tigray; Afar; Amhara; Oromia;S...

• Cosmology - astronomy.

  In 1917 American scientist Harlow Shapley measured the distance to several groups of stars known as globular clusters. He measured these distances by using amethod developed in 1912 by American astronomer Henrietta Leavitt. Leavitt’s method relates distance to variations in brightness of Cepheid variables, a class of starsthat vary periodically in brightness. Shapley’s distance measurements showed that the clusters were centered around a point far from the Sun. The arrangement of theclusters was...

• Butterflies and Moths - biology.

  The smallest butterflies are certain blues that have wingspans of a mere 0.7 cm (0.25 in). The largest are the female giant birdwings of Papua New Guinea, whichmeasure up to 30 cm (12 in) across. Moths range in size from tiny Microlepidoptera, several groups of small moths with wings no more than 0.16 cm (0.06 in) across, togiant silk moths, such as the atlas moth, which may exceed 30 cm (12 in) in wingspan. IV REPRODUCTION AND LIFE CYCLE Butterflies locate potential mates by sight, identifyin...

• Johann Sebastian Bach I INTRODUCTION Johann Sebastian Bach (1685-1750), German composer and one of the world's greatest musical geniuses.

  Bach served nine years at the Weimar court, first as organist and then, from 1714, as concertmaster as well. His employer, Wilhelm Ernst, duke of Weimar, was a greatadmirer of the organ, and spurred by the duke’s enthusiasm Bach proceeded to compose a vast number of unprecedented works for the instrument: the Orgelbüchlein (“Little Organ Book”), a collection of small chorale preludes for the church year; the so-called Great Eighteen Chorales of larger size; and a series of dramatic preludes a...

• Western Music I INTRODUCTION Bizet's Carmen Georges Bizet's Carmen, first performed in Paris in 1875, was a milestone in the history of French opera.

  church ceremonies during the period from the 5th to the 7th century. Roman chant became known as Gregorian chant after Pope Gregory I, the Great, who may havecomposed some of the melodies and who actively encouraged an orderly, ritualized use of music by the church. Because Gregory and later popes preferred Gregorianchant to the varieties that had developed elsewhere in Europe, Gregorian chant eventually superseded most of the others. Gregorian and other chant styles arepreserved in many manuscr...

• 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...

• Airplane.

  For example, the Anglo-French Concorde, a commercial supersonic aircraft, was generally limited to over-water routes, or to those over sparsely populated regions ofthe world. This limitation impacted the commercial viability of the Concorde, which ended its regular passenger service in October 2003. Designers today believe theycan help lessen the impact of sonic booms created by supersonic airliners but probably cannot eliminate them. One of the most difficult practical barriers to supersonic fl...

• American Literature: Poetry I INTRODUCTION Phyllis McGinley American poet and author Phyllis McGinley composed light, witty verse, much of which deals with family life.

  Taylor, a poet of great technical skill, wrote powerful meditative poems in which he tested himself morally and sought to identify and root out sinful tendencies. In“God's Determinations Touching His Elect” (written 1680?), one of Taylor’s most important works, he celebrates God's power in the triumph of good over evil in thehuman soul. All of Taylor’s poetry and much of Bradstreet’s served generally personal ends, and their audience often consisted of themselves and their family andclosest frie...

• France - country.

  In both the Paris and Aquitaine basins, fertile soils derived from limestone and wind-deposited dust, called loess, have supported prosperous agriculture since ancienttimes. Other lowlands in France are scattered and relatively small. They include the Alsace Plain in the east, bordering Germany, the valley of the Rhône River in thesoutheast, and the Languedoc Plain along the Mediterranean coast. A2 Uplands France contains several regions of uplands, the worn down remains of ancient mountain sys...

• Africa.

  The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...

• Africa - Geography.

  The highest elevations in Africa are found in the various ranges of East Africa. After Kilimanjaro, the next highest peaks are Mount Kenya (5,199 m/17,057 ft), north ofKilimanjaro in central Kenya; Margherita Peak (5,109 m/ 16,762 ft) in the Ruwenzori Range on the border between Uganda and the Democratic Republic of the Congo(DRC); Ras Dashen (4,620 m/ 15,157 ft) in the Ethiopian Highlands of northern Ethiopia; Mount Meru (4,565 m/ 14,977 ft), close to Kilimanjaro in Tanzania; and MountElgon (4,...

• China - country.

  North China lies between the Mongolian Steppe on the north and the Yangtze River Basin on the south. It stretches west from the Bo Hai gulf and the Yellow Sea to theeastern edge of the Tibetan Plateau. Administratively, North China includes Beijing and Tianjin municipalities; Shandong and Shanxi provinces; most of Hebei, Henan,and Shaanxi provinces; and portions of Ningxia Hui Autonomous Region and of Jiangsu, Anhui, and Gansu provinces. Humans have lived in the agriculturally rich region of Nor...