1657 résultats pour "havas"

• Coral Reef.

  sensitive to particles of mud or sediment settling on them, which means that corals rarely grow close to rivers or other sources of sediment. In the sea, light is filteredout by depth, so reef-building corals can only grow in relatively shallow water. Even in the clearest oceans few reef-building corals grow below a depth of 80 to 100 m(260 to 328 ft). Although corals need nutrients, they cannot thrive in areas where there are large amounts of nutrients. Typically, microscopic organisms in the p...

• 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...

• Abortion.

  Intact dilation and extraction, also referred to as a partial birth abortion, consists of partially removing the fetus from the uterus through the vaginal canal, feet first,and using suction to remove the brain and spinal fluid from the skull. The skull is then collapsed to allow complete removal of the fetus from the uterus. III SOCIAL AND ETHICAL ISSUES Abortion has become one of the most widely debated ethical issues of our time. On one side are pro-choice supporters—individuals who favor a...

• From A Vindication of the Rights of Woman - anthology.

  Ignorance is a frail base for virtue! Yet, that it is the condition for which woman was organized, has been insisted upon by the writers who have most vehementlyargued in favour of the superiority of man; a superiority not in degree, but essence; though, to soften the argument, they have laboured to prove, with chivalrousgenerosity, that the sexes ought not to be compared; man was made to reason, woman to feel: and that together, flesh and spirit, they make the most perfect whole, byblending hap...

• Tiger - biology.

  have a simple digestive system designed to process meat so that the nutrients can be readily absorbed into the bloodstream. With the exception of white tigers, which have blue eyes, all tigers have yellow eyes. Tigers mainly use vision to find prey. Although tigers see about as well as humansduring the day, their large eye openings gather more light than do human eyes, making tiger night vision far superior to that of humans. In addition, a special structurein the tiger’s eye, called the tapetu...

• Churchill: "The Sinews of Peace" On March 5, 1946, in a

  safeguards to make it effective, these powers would naturally be confided to that world organisation. Now I come to the second danger of these two marauders which threatens the cottage, the home, and the ordinary people—namely, tyranny. We cannot be blind tothe fact that the liberties enjoyed by individual citizens throughout the British Empire are not valid in a considerable number of countries, some of which are verypowerful. In these States control is enforced upon the common people by variou...

• President of the United States.

  Democrats and Republicans—select delegates to attend their party conventions. Primary voters and caucus participants choose delegates who will support their favoredcandidate at the convention. The party conventions, held in the summer before the November general election, formally nominate the winner of the primaries andcaucuses. Would-be candidates crisscross the states that hold the earliest primaries, especially New Hampshire, which holds the country’s first primary, usually in mid-February....

• Elephant - biology.

  B Trunk An elephant's nose and upper lip are combined in a long, limber trunk, an exceptionally supple appendage with an estimated 150,000 muscles. The versatile trunk actslike a hand for grasping low-growing shrubs and other food and placing it into the mouth; an arm for breaking off tree branches; or a snorkel for breathing when theelephant's body is submerged. Elephants also use their trunks to suck up water and squirt it into their mouths for drinking or over their bodies for bathing. Nostr...

• Rain Forest.

  dropped into the heart of the forest by helicopters. Suspended from the crane’s long, movable arm is a large gondola that functions as a mobile treetop laboratory.Moving from tree to tree, forest researchers collect specimens, conduct experiments, and observe life in the canopy frontier. The highest stratum of the rain forest is made up of the emergent trees, those individuals that stick up above the forest canopy. Emergents, which do not form acontinuous layer, are usually the giants of the for...

• Dog. I INTRODUCTION Dog, mammal generally considered to be the first domesticated animal.

  French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...

• Dog - biology.

  French word for butterfly because it has ears that resemble butterfly wings, is a happy, friendly dog, suitable for small living spaces. The final dog group, nonsporting ,includes a wide variety of purebreds that differ in size, coat, overall appearance, and personality, from the shorthaired spotted dalmatian to the curly-haired poodle. V DOG BEHAVIOR Instinctive behaviors of the domestic dog are comparable to those of its wild relatives, the wolf, coyote, fox, and jackal. Unlike trained behavi...

• Saudi Arabia - country.

  C Natural Resources Some of the world’s largest oil and natural gas fields lie beneath Saudi Arabia and its offshore waters, representing the country’s most economically important naturalresource. In 2007 Saudi Arabia’s oil reserves were estimated at 264 billion barrels. Before the discovery and exploitation of these reserves in the mid-20th century,Saudi Arabia was one of the poorest countries in the world. Its relatively small population subsisted in a harsh environment with little agricultur...

• Programming Language.

  Logic languages use logic as their mathematical base. A logic program consists of sets of facts and if-then rules, which specify how one set of facts may be deducedfrom others, for example: If the statement X is true, then the statement Y is false. In the execution of such a program, an input statement can be logically deduced from other statements in the program. Many artificial intelligence programs are writtenin such languages. IV LANGUAGE STRUCTURE AND COMPONENTS Programming languages use...

• Collectibles and Collecting.

  common blond and thus commands a higher price. If there are different variations to a collectible, the least common one is usually worth more. Often there areinteresting stories behind rarities, such as the highly sought-after 1909 Honus Wagner baseball card. At that time tobacco companies manufactured and distributedbaseball cards, and when the antitobacco Wagner complained, his card was pulled from production. Very few copies in good condition have ever been found. C Age Age is often an indic...

• Bill of Rights.

  accused has the right to “confront”—that is, to cross-examine witnesses who testify against him or her at trial. Those accused also have a right to subpoena (compel)supporting witnesses to testify in court and to have a lawyer assist in their legal defense. G Seventh Amendment In Suits at common law, where the value in controversy shall exceed twenty dollars, the right of trial by jury shall be preserved, and no fact tried by a jury, shall beotherwise re-examined in any Court of the United Stat...

• Bill of Rights - U.

  accused has the right to “confront”—that is, to cross-examine witnesses who testify against him or her at trial. Those accused also have a right to subpoena (compel)supporting witnesses to testify in court and to have a lawyer assist in their legal defense. G Seventh Amendment In Suits at common law, where the value in controversy shall exceed twenty dollars, the right of trial by jury shall be preserved, and no fact tried by a jury, shall beotherwise re-examined in any Court of the United Stat...

• Wisconsin (state) - geography.

  -6° C (22° F) in the southeast, along the Lake Michigan shore. During winter extremely cold weather persists for several weeks at a time. C2 Precipitation Average annual precipitation ranges from 700 to 800 mm (28 to 32 in). Rainfall is generally heaviest during the spring and summer, and snowfall is generally moderatein the south, but can be quite heavy in the north. Thunderstorms, sometimes accompanied by devastating tornadoes, are common in spring and summer, particularly inthe southern part...

• Wisconsin (state) - USA History.

  -6° C (22° F) in the southeast, along the Lake Michigan shore. During winter extremely cold weather persists for several weeks at a time. C2 Precipitation Average annual precipitation ranges from 700 to 800 mm (28 to 32 in). Rainfall is generally heaviest during the spring and summer, and snowfall is generally moderatein the south, but can be quite heavy in the north. Thunderstorms, sometimes accompanied by devastating tornadoes, are common in spring and summer, particularly inthe southern part...

• Arab Music I INTRODUCTION Umm Kulthum Egyptian singer Umm Kulthum was revered throughout Egypt, North Africa, and the Near East for her powerful voice and improvisational skill.

  The rhythmic structure of Arab music is similarly complex. Rhythmic patterns have up to 48 beats and typically include several downbeats (called dums ) as well as upbeats (called taks) and silences, or rests. To grasp a rhythmic mode, the listener must hear a relatively long pattern. Moreover, the performers do not simply play the pattern; they elaborate upon and ornament it. Often the pattern is recognizable by the arrangement of downbeats. The Rhythm in Arab Music illustration demonstratesa...

• Saskatchewan (province) - Geography.

  The length of the frost-free season varies within the province. In the southwest, particularly in the valley lands along the South Saskatchewan River, the frost-freeperiod ranges from 150 to 160 days. Regina enjoys about 123 frost-free days, and Saskatoon has about 111. The far north has only from 85 to 95 frost-free days. One important characteristic of Saskatchewan’s climate is the great variability in temperature and precipitation from year to year, which is often critical for agriculture.The...

• Saskatchewan (province) - Canadian History.

  The length of the frost-free season varies within the province. In the southwest, particularly in the valley lands along the South Saskatchewan River, the frost-freeperiod ranges from 150 to 160 days. Regina enjoys about 123 frost-free days, and Saskatoon has about 111. The far north has only from 85 to 95 frost-free days. One important characteristic of Saskatchewan’s climate is the great variability in temperature and precipitation from year to year, which is often critical for agriculture.The...

• Mental Illness.

  note that under this definition, political dissidents could be considered mentally ill for refusing to accept the dictates of their government. VI PREVALENCE Mental illness affects people of all ages, races, cultures, and socioeconomic classes. The prevalence of mental illness refers to how many people experience a mentalillness during a specified time period. A United States and Worldwide In the United States, researchers estimate that about 24 percent of people 18 or older, or about 44 mill...

• Labor Union.

  B The Legal Environment The legal environment, which permits certain types of union activities and prohibits others, also influences the extent of union organization. States with right-to-worklaws have much lower unionization rates than other states. In the United States, the states with the lowest unionization rates are North Carolina, South Carolina, SouthDakota, and Arkansas—states that have right-to-work laws. In 2000 the unionization rate in these states ranged from 4.44 percent to 6.7 per...

• Pennsylvania - geography.

  B Rivers and Lakes There are three major river basins in Pennsylvania: the Susquehanna, the Ohio, and the Delaware. Together they drain more than 90 percent of Pennsylvania’s landarea. Most of eastern and central Pennsylvania is drained by the Susquehanna and Delaware systems. The western part of the state is drained by the Allegheny andMonongahela rivers, which join at Pittsburgh to form the Ohio. In addition to the three major river basins, short streams flowing into Lake Erie drain the north...

• Pennsylvania - USA History.

  B Rivers and Lakes There are three major river basins in Pennsylvania: the Susquehanna, the Ohio, and the Delaware. Together they drain more than 90 percent of Pennsylvania’s landarea. Most of eastern and central Pennsylvania is drained by the Susquehanna and Delaware systems. The western part of the state is drained by the Allegheny andMonongahela rivers, which join at Pittsburgh to form the Ohio. In addition to the three major river basins, short streams flowing into Lake Erie drain the north...

• Ohio - geography.

  conflict with modified Gulf air and causing frontal or cyclonic storms. Gulf air is dominant in summer. In fall, polar air passing over Lake Erie is modified, delaying thekilling frost along the adjacent shoreline. C1 Temperatures The mean annual temperatures for the state range from 9° C (48° F) in the northeast to 13° C (55° F) in the south. Average January temperatures range from -4° C(24° F) in the west to 2° C (35° F) in the south. July averages are 24° C (76° F) in the south and 23° C (73...

• Ohio - USA History.

  conflict with modified Gulf air and causing frontal or cyclonic storms. Gulf air is dominant in summer. In fall, polar air passing over Lake Erie is modified, delaying thekilling frost along the adjacent shoreline. C1 Temperatures The mean annual temperatures for the state range from 9° C (48° F) in the northeast to 13° C (55° F) in the south. Average January temperatures range from -4° C(24° F) in the west to 2° C (35° F) in the south. July averages are 24° C (76° F) in the south and 23° C (73...

• Dolphin (aquatic mammal) - biology.

  Scientists have observed dolphins displaying three types of caregiving behaviors: standing by, excitement, and supporting. In standing-by behavior, dolphins remain inthe vicinity of an injured or ill companion without offering aid. In excitement behavior, dolphins swim swiftly in circles around an injured dolphin, responding aggressivelytoward threats to the injured animal. For instance, they may bite harpoon lines or charge boats that come too close to the animal. In supporting behavior, one or...

• Missouri - geography.

  Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...

• Missouri - USA History.

  Saint Francois Mountains, at the eastern end of the crest of the dome. Only in these mountains have the sedimentary rocks been sufficiently eroded away so that theunderlying igneous rocks are exposed. They form the rounded, knoblike peaks of an old mountain range. The peaks project, in isolation or in clusters, between 230 and300 m (750 and 1,000 ft) above the surrounding sedimentary basins. One of these knobs, Taum Sauk Mountain, reaches 540 m (1,772 ft) above sea level and is thehighest point...

• World Wide Web.

  browser does not display the URL for the user. Instead, to indicate that an item is selectable, the browser changes the color of the item on the screen and keeps theURL associated with the link hidden. When a user clicks on an item that corresponds to a selectable link, the browser consults the hidden information to find theappropriate URL, which the browser then follows to the selected page. Because a link can point to any page in the Web, the links are known as hyperlinks. See also Hypermedia...

• Animal - biology.

  Vertebrates are customarily divided into cold-blooded and warm-blooded animals, but these labels are not very precise. Biologists normally use the terms ectoderm and endoderm to describe temperature regulation more accurately. An ectoderm is an animal whose temperature is dictated by its surroundings, while an endoderm is one that keeps its body at a constant warm temperature by generating internal heat. Reptiles, amphibians, and fish are ectoderms. Although they do not maintain a constant wa...

• Goose - biology.

  Branta comes from a German word meaning “burned” and all of the geese in this genus have black plumage somewhere on their bodies. The brant, a sea goose that also belongs to this genus, is found on both coasts of North America. Brants are darker than barnacle and Canada geese and similar in size to the smallest Canadageese. Like the Canada and barnacle goose, the brant nests in Arctic regions. But unlike them, it winters chiefly on salt water. Instead of the white cheeks of Canadaand barnacle g...

• United Nations.

  and programs to carry out its recommendations. It elects members to serve on certain agencies and programs, and it coordinates those programs through variouscommittees. B Security Council The Security Council is the most powerful body in the UN. It is responsible for maintaining international peace, and for restoring peace when conflicts arise. Its decisionsare binding on all UN members and have the force of international law. The Security Council has the power to define what is a threat to sec...

• Anthropology.

  humans, such as tools, pottery, and buildings) and human fossils (preserved bones). They also examine past environments to understand how natural forces, such as climate and available food, shaped the development of human culture. Some archaeologists study cultures that existed before the development of writing, a time knownas prehistory . The archaeological study of periods of human evolution up to the first development of agriculture, about 10,000 years ago, is also called paleoanthropology....

• Spider (arthropod) - biology.

  The spider’s abdomen is soft and saclike. On the underside of the tip of the abdomen are three pairs of spinnerets. Each spinneret is studded with many fine, hairliketubes called spigots, which produce a variety of silk threads. The spigots lead to several large silk glands inside the abdomen. Silk is formed as a liquid inside theseabdominal glands. As the silk is drawn out through the spigots, protein molecules within the silk line up parallel to one another, causing the silk to harden and form...

• Excerpt from A Christmas Carol - anthology.

  External heat and cold had little influence on Scrooge. No warmth could warm, no wintry weather chill him. No wind that blew was bitterer than he, no falling snowwas more intent upon its purpose, no pelting rain less open to entreaty. Foul weather didn’t know where to have him. The heaviest rain, and snow, and hail, and sleet,could boast of the advantage over him in only one respect. They often “came down” handsomely and Scrooge never did. Nobody ever stopped him in the street to say, with g...

• Jim Thorpe's Olympic Triumph.

  Thorpe's decathlon gold medal was widely hailed in the United States. James E. Sullivan, chairman of the U.S. Olympic Committee, said it was particularlyimpressive in light of criticisms that the American team consisted of too many “specialists” in track and field. “His all-around work was certainly sensational,”Sullivan told the New York Times. ”In fact, the pentathlon was added to the games especially for the benefit of foreigners, but we have shown that we can produce all-around men, too. I...

• Hinduism.

  they do not share any basic terms. B Sanātana Dharma Evidence from inscriptions indicates that Hindus had begun to use the word dharma for their religion by the 7th century. After other religions of Indian origin also began to use this term, Hindus then adopted the expression san ātana dharma to distinguish their dharma from others. The word san ātana, meaning immemorial as well as eternal, emphasized the unbroken continuity of the Hindu tradition in contrast to the other dharmas . The Bu...

• God. I INTRODUCTION God, the center and focus of religious faith, a holy

  C Islam Islam arose as a powerful reaction against the ancient pagan cults of Arabia, and as a consequence it is the most starkly monotheistic of the three biblically rootedreligions. The name Allah means simply “the God.” He is personal, transcendent, and unique, and Muslims are forbidden to depict him in any creaturely form. The primary creed is that “There is no god but Allah, and Muhammad is the apostle of Allah.” Allah has seven basic attributes: life, knowledge, power, will, hearing, se...

• Extinction (biology) - biology.

  III ROLE OF MASS EXTINCTION IN EVOLUTION Historically biologists—most famous among them British naturalist Charles Darwin—assumed that extinction is the natural outcome of competition between newlyevolved, adaptively superior species and their older, more primitive ancestors. These scientists believed that newer, more highly evolved species simply drove less well-adapted species to extinction. That is, historically, extinction was thought to result from evolution. It was also thought that this...

• Liver.

  by bacterial infections. But hepatitis is most often caused by one of several viruses. The hepatitis A virus (HAV) can produce flulike symptoms and jaundice, but manypeople who contract it have no symptoms. The disease tends to resolve on its own. Because HAV lives in feces in the intestinal tract, hepatitis A is prevalent in areaswhere drinking water is contaminated with raw sewage. Good hygiene practices and a hepatitis A vaccination are effective measures of prevention. Hepatitis B is a more...

• From Bulfinch's Mythology: Perseus and Medusa - anthology.

  The Sea-monster Perseus, continuing his flight, arrived at the country of the Æthiopians, of which Cepheus was king. Cassiopeia his queen, proud of her beauty, had dared to compareherself to the Sea-Nymphs, which roused their indignation to such a degree that they sent a prodigious sea-monster to ravage the coast. To appease the deities,Cepheus was directed by the oracle to expose his daughter Andromeda to be devoured by the monster. As Perseus looked down from his aerial height he beheld thev...

• 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...

• Algeria - country.

  areas to fishing. National parks, including the giant Tassili N’Ajjer National Park in the eastern corner of the country, comprise a large proportion of the protected area. The effects of Algeria’s human population on the fragile landscape have been severe. The greatest ecological threats are deforestation and burning of scrub vegetation,conversion of steppe habitat to arable land, and soil erosion due to overgrazing and poor farming practices. Pollution of Mediterranean coastal waters is pervas...

• Deoxyribonucleic Acid - biology.

  bacterium Escherichia coli . In 1998 scientists achieved the milestone of sequencing the complete genome of a multicellular organism—a roundworm identified as Caenorhabditis elegans . The Human Genome Project, an international research collaboration, was established to determine the sequence of all of the 3 billion nucleotide base pairs that make up thehuman genetic material. In 2003 scientists completed the sequencing of the human genome. The project identified nearly all of the estimated 20...

• North Dakota - geography.

  Bismarck, the growing season averages 134 days, as the average date of the last killing frost is May 11 and that of the first killing frost is September 22. The length ofthe growing season drops to about 110 days in the northerly reaches of the state. The long periods of summer sunshine at this latitude, providing as much as 16 hoursof daylight in summer, help crops to mature quickly, thus compensating somewhat for the relatively short growing season. Temperatures in the north are, on the averag...

• North Dakota - USA History.

  Bismarck, the growing season averages 134 days, as the average date of the last killing frost is May 11 and that of the first killing frost is September 22. The length ofthe growing season drops to about 110 days in the northerly reaches of the state. The long periods of summer sunshine at this latitude, providing as much as 16 hoursof daylight in summer, help crops to mature quickly, thus compensating somewhat for the relatively short growing season. Temperatures in the north are, on the averag...

• El Salvador - country.

  III PEOPLE The Spanish subjugated the native population of El Salvador in the 16th century. Few Spanish women came to the country, however, so many Spanish men took NativeAmerican women as their mates. Today nearly 90 percent of the population is mestizo , of mixed European and Native American descent. People of purely Native American descent represent about 5 to 10 percent of the population, while people of European descent represent only about 1 percent. El Salvador’s population, 5.2 millio...