483 résultats pour "any"

• Astrobiology - astronomy.

  water to help reactions along. American chemists Stanley Miller and Harold Urey tested part of Oparin and Haldane’s hypothesis in the early 1950s by simulating conditions of the early Earth. In whathas become known as the Miller-Urey experiment, the two scientists connected two flasks with a loop of glass tubing that allowed the gases to pass between the flasks.They filled the upper flask with methane, ammonia, and hydrogen—components thought to have been in the early atmosphere. They filled the...

• Mountain Climbing.

  teeth on one side, and a straight, flat, metal blade called an adze on the other. Ice axes have many uses. One of the most common is to help the climber stay balanced on steep slopes. The climber swings the axe with a short, quick movement to lodge the pick in snow or ice, creating a secure anchor. If a climber should slip and beginsliding down a snowfield, a self-arrest can be performed by turning face down on the snow and burying the pick in the snow surface. The climber’s weight over the...

• Spread of Islam - History.

  Muhammad died in 632 and was succeeded by Abu Bakr, the father of Muhammad’s favorite wife, Aisha. Abu Bakr was the first caliph ( khalifah, Arabic for “successor”) of Islam. Like Muhammad, Abu Bakr was a member of the Quraysh clan. While neither Abu Bakr nor any subsequent caliph claimed the role of prophet, they wereleaders of this new religious enterprise that was quickly becoming a political entity as well. The first four caliphs, all of whom were selected by some form of council ofMuslims,...

• Fire - chemistry.

  were usually natural caves. Eventually people learned to dip branches in pitch to form torches. They created crude lamps by filling a hollowed out piece of stone withmoss soaked in oil or tallow (a substance derived from animal fat). By cooking with fire, prehistoric people made the meat of the animals they killed more palatable and digestible. They learned to preserve meat by smoking it over a fire,vastly decreasing the danger of periodic starvation. Cooking also enabled them to add some for...

• George Washington I INTRODUCTION George Washington (1732-1799), first president of the United States (1789-1797) and one of the most important leaders in United States history.

  A2 Promotion This was Washington’s first experience with the difficulties of raising troops while lacking equipment, clothing, and funds. Apparently he thought his efforts worthy ofsome recognition and successfully applied to Dinwiddie for a lieutenant colonel’s commission. He left Alexandria, Virginia, early in April with about 150 poorly equippedand half-trained troops. A3 First Battles Before he had advanced very far, Washington received news that the French had driven Trent’s men back from...

• George Washington.

  A2 Promotion This was Washington’s first experience with the difficulties of raising troops while lacking equipment, clothing, and funds. Apparently he thought his efforts worthy ofsome recognition and successfully applied to Dinwiddie for a lieutenant colonel’s commission. He left Alexandria, Virginia, early in April with about 150 poorly equippedand half-trained troops. A3 First Battles Before he had advanced very far, Washington received news that the French had driven Trent’s men back from...

• George Washington

  A2 Promotion This was Washington’s first experience with the difficulties of raising troops while lacking equipment, clothing, and funds. Apparently he thought his efforts worthy ofsome recognition and successfully applied to Dinwiddie for a lieutenant colonel’s commission. He left Alexandria, Virginia, early in April with about 150 poorly equippedand half-trained troops. A3 First Battles Before he had advanced very far, Washington received news that the French had driven Trent’s men back from...

• Venezuela - country.

  Venezuela has six navigable rivers. Of the thousand or more streams in the country, the majority flow into the Orinoco. The Orinoco flows east across central Venezuelaand drains approximately four-fifths of the total area of the country. With the tributaries—the Apure, Meta, and Negro rivers—it forms the outlet into the Atlantic Oceanfor the waters of much of the interior of Colombia, as well as of inland Venezuela. F Climate The climate of Venezuela is tropical on the Llanos and along the coas...

• Segregation in the United States - U.

  acts of discrimination. Writing for the court, Justice Joseph Bradley declared: “When a man has emerged from slavery, and by the aid of beneficent legislation ... theremust be some stage in the progress of his elevation when he takes the rank of a mere citizen, and ceases to be the special favorite of the laws, and when his rights as acitizen, or a man, are to be protected in the ordinary modes by which other men’s rights are protected.” Rather than being the “special favorites” of the law, blac...

• Mars (planet) - astronomy.

  The Martian core is probably much like Earth’s, consisting mostly of iron, with a small amount of nickel. If other light elements, particularly sulfur, exist there as well, thecore may be larger than presently thought. From studying Earth’s magnetic field and core, scientists theorize that the motions of the liquid rock in Earth’s core generateits magnetic field. Mars does not have a significant magnetic field, so scientists believe that Mars’s core is probably solid. However, spacecraft data in...

• Puerto Rico - geography.

  the length of the day remains fairly constant throughout the year. San Juan has a mean July temperature of 28°C (83°F) and a mean January temperature of 25°C (77°F). The average temperature of the seawater surrounding theisland is 27°C (81°F), with little variation during the course of the year. The entire island is cooled by the trade winds from the northeast. This air also contains much water vapor. As the air is forced to rise over the mountains, it becomescooler and the water vapor condenses...

• Arithmetic I INTRODUCTION Arithmetic, branch of mathematics that arises from counting, the most basic mathematical operation.

  Subtract the units: 6 - 3 = 3. Then subtract the tens column: 6 – 2 = 4. The results of these two single-digit subtractions, written side by side, provide the answer: Subtraction is a bit more complicated if we need to subtract a larger digit from a smaller one. For example, when subtracting 47 from 92, the units value (7) of 47 isgreater than the units value (2) of 92. We can handle this situation using a procedure called borrowing, which is like carrying in reverse. Ten units can be borrowe...

• Japan - country.

  island’s fertile soils support agriculture and provide the vast majority of Japan’s pasturelands. In addition, Hokkaidō contains coal deposits, and the cold currents off itsshores supply cold-water fish. Winters are long and harsh, so most of Hokkaid ō is lightly settled, housing about 5 percent of Japan’s population on approximately 20 percent of its land area. However,its snowy winters and unspoiled natural beauty attract many skiers and tourists. Hokkaid ō is thought of as Japan’s northern fr...

• Islam.

  commanded to face the Kaaba, an ancient shrine in the city of Mecca. The Qur’an also refers to the recitation of parts of the Qur’an as a form of prayer. However, evenwith its numerous references, the Qur’an alone does not give exact instructions for this central ritual of prayer. The most detailed descriptions of the rituals for prayer derive from the example set by the prophet Muhammad and are preserved in later Islamic traditions. Somedetails of these rituals vary, however all Muslims agree t...

• Elementary Particles I INTRODUCTION Structure of Matter Modern physics has revealed successively deeper layers of structure in ordinary matter.

  The most fundamental particles that make up matter fall into the fermion category. These fermions cannot be split into anything smaller. The particles that carry theforces acting on matter and antimatter are bosons called force carriers. Force carriers are also fundamental particles, so they cannot be split into anything smaller.These bosons carry the four basic forces in the universe: the electromagnetic, the gravitational, the strong (force that holds the nuclei of atoms together), and the wea...

• American Revolution.

  C1 The South Southern agriculture was founded on the cultivation of tobacco, wheat, and corn in Virginia, Maryland, and North Carolina, and of rice and indigo (a blue dye) in SouthCarolina and Georgia. There was a large demand for these crops in Europe. These crops were cultivated with the help of black slaves imported from Africa. The whiteplanter class in the South was the most powerful, both politically and economically. C2 The North Wheat was the main cash crop of the mid-Atlantic colonies...

• American Revolution - U.

  C1 The South Southern agriculture was founded on the cultivation of tobacco, wheat, and corn in Virginia, Maryland, and North Carolina, and of rice and indigo (a blue dye) in SouthCarolina and Georgia. There was a large demand for these crops in Europe. These crops were cultivated with the help of black slaves imported from Africa. The whiteplanter class in the South was the most powerful, both politically and economically. C2 The North Wheat was the main cash crop of the mid-Atlantic colonies...

• Texas - geography.

  D Climate Eastern Texas has a humid subtropical climate, while a semiarid low latitude climate prevails in central areas, and an arid low latitude climate in the extreme west. Alongthe coast the climate is much milder, with fewer extremes in temperatures. Hurricanes sometimes hit the coastal areas of Texas from late July through September, andtornadoes are common in north-central Texas in April and May. D1 Temperature Summers are hot throughout the state, and temperatures exceeding 35°C (95°F)...

• Texas - USA History.

  D Climate Eastern Texas has a humid subtropical climate, while a semiarid low latitude climate prevails in central areas, and an arid low latitude climate in the extreme west. Alongthe coast the climate is much milder, with fewer extremes in temperatures. Hurricanes sometimes hit the coastal areas of Texas from late July through September, andtornadoes are common in north-central Texas in April and May. D1 Temperature Summers are hot throughout the state, and temperatures exceeding 35°C (95°F)...

• Christopher Columbus I INTRODUCTION Christopher Columbus (1451-1506), Italian-born Spanish navigator who sailed west across the Atlantic Ocean in search of a route to Asia but achieved fame by making landfall in the Americas instead.

  explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...

• Christopher Columbus.

  explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...

• Christopher Columbus.

  explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...

• Christopher Columbus - explorer.

  explorers, adventurers, entrepreneurs, merchants, and any others who saw their fortunes tied to the trade winds and ocean currents. Columbus’s brother Bartholomewworked in Lisbon as a mapmaker, and for a time the brothers worked together as draftsmen and book collectors. Later that year, Columbus set sail on a convoy loadedwith goods to be sold in northern Atlantic ports. In 1478 or 1479 Columbus met and married Felipa Perestrello e Moniz, the daughter of a respected, though relatively poor, nob...

• Illinois - geography.

  the state before joining the Mississippi River at Grafton. The Illinois has been deepened and straightened and forms part of the Illinois Waterway. The watershed between rivers that flow into the Mississippi river system and rivers that flow into the Great Lakes is low and in many places is not easily discernible. Inwhat is now the Chicago area, explorers had little difficulty portaging, or carrying, their canoes over the low watershed between the Des Plaines River, which flows intothe Illinois,...

• Illinois - USA History.

  the state before joining the Mississippi River at Grafton. The Illinois has been deepened and straightened and forms part of the Illinois Waterway. The watershed between rivers that flow into the Mississippi river system and rivers that flow into the Great Lakes is low and in many places is not easily discernible. Inwhat is now the Chicago area, explorers had little difficulty portaging, or carrying, their canoes over the low watershed between the Des Plaines River, which flows intothe Illinois,...

• India - country.

  delta in the north, are intensely farmed. B Rivers and Lakes The rivers of India can be divided into three groups: the great Himalayan rivers of the north, the westward-flowing rivers of central India, and the eastward-flowingrivers of the Deccan Plateau and the rest of peninsular India. Only small portions of India’s rivers are navigable because of silting and the wide seasonal variation inwater flow (due to the monsoon climate). Water transport is thus of little importance in India. Barrages,...

• Music I INTRODUCTION World Music Tour Click on the instruments to hear music from around the world.

  Duke EllingtonAmerican composer, bandleader, and pianist Duke Ellington endures as perhaps the most important pioneer in big-bandjazz. Ellington and his orchestra shared a special interdependent relationship: Using the band as his musical workshop,Ellington derived his orchestra’s tone coloring from the unique sound qualities of the group’s individual players. Thisparticular style was later dubbed the “Ellington Effect” by jazz arranger Billy Strayhorn, who also wrote one of the band’ssignature...

• From Walden - anthology.

  instant? We should live in all the ages of the world in an hour; ay, in all the worlds of the ages. History, Poetry, Mythology!—I know of no reading of another'sexperience so startling and informing as this would be. The greater part of what my neighbors call good I believe in my soul to be bad, and if I repent of any thing, it is very likely to be my good behavior. What demonpossessed me that I behaved so well? You may say the wisest thing you can old man,—you who have lived seventy years,...

• 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...

• Meteorology.

  to find the corresponding relative humidity and dew-point temperature. III SPECIAL METEOROLOGICAL INSTRUMENTS Meteorologists have developed several sophisticated instruments that measure multiple physical characteristics of the air simultaneously and at more than one location.The most important of these special instruments are radiosondes, Doppler radar, and weather satellites. A Radiosonde A radiosonde measures air temperature, air pressure, and humidity from the earth’s surface up to an alt...

• Taxation.

  Thus, corporate income faces a higher tax burden than income earned by individuals or by other types of businesses. Tax legislation passed in 2003 in the United Statesattempted to address this issue by lowering the tax rate on dividends. Some economists have proposed abolishing the corporate income tax and instead taxing the owners of corporations (shareholders) through the personal income tax.Other students of the tax system see the corporate income tax as the price corporations pay in return f...

• Psychotherapy.

  Other managed-care companies pay therapists a set fee to meet with a client for up to a specified maximum number of sessions depending on the nature of theproblem, free of interference from case reviewers. For example, a managed-care firm may pay a therapist $200 to hold up to eight sessions with a person. If the clientuses all eight sessions, the therapist normally loses money. But if treatment stops after two or three sessions, the therapist makes a profit. This relatively new system iscontrov...

• Modern Art I INTRODUCTION American Gothic American Gothic was painted by the 20th-century American artist Grant Wood in 1930.

  while at the other side a woman in black appears to mourn the end of her participation in the dance. Click on the buttonsto learn more.© Microsoft Corporation. All Rights Reserved. In view of this diversity, it is difficult to define modern art in a way that includes all of 20th-century Western art. For some critics, the most important characteristic ofmodern art is its attempt to make painting and sculpture ends in themselves, thus distinguishing modernism from earlier forms of art that had con...

• Evolution - biology.

  genetic diversity to extinction. Sexual reproduction ensures that the genes in a population are rearranged in each generation, a process termed recombination. Although the combinations of genes inindividuals change with each new generation, the gene frequency, or ratio of different alleles in the entire population, remains relatively constant if no evolutionaryforces act on the population. One such force is the introduction of new genes into the genetic material of the population, or gene pool...

• Supreme Court of the United States.

  The Constitution does not specify formal qualifications for membership on the Supreme Court. From the beginning, though, justices have all been lawyers, and mostpursued legal and political careers before serving on the Court. Many justices served as members of Congress, governors, or members of the Cabinet. One president,William Howard Taft, was later appointed chief justice. Some justices came to the Court from private law practice, and others were appointed from positions as lawprofessors. Man...

• Turkmenistan - country.

  A Ethnic Groups With Turkmens constituting 77 percent of the population, Turkmenistan is the most ethnically homogeneous of the Central Asian republics. Uzbeks make up the largestminority group, with about 9 percent of the population. Other ethnic groups include Russians, Kazakhs, Tatars, Ukrainians, Azeris (ethnic Azerbaijanis), Armenians, andBaluch. In 1993 a bilateral treaty between Turkmenistan and Russia granted dual citizenship to Russians in the republic. At the 1995 census Russians cons...

• Advertising.

  Advertising agencies make money in a variety of ways. When the agency uses the client’s advertising budget to buy time for an ad on the radio or on television or whenit buys space for an ad in a newspaper or magazine, the media outlet allows the agency to keep 15 percent of the cost of the space or the time as a commission. The15 percent commission has become an advertising industry standard and usually accounts for the largest portion of the agency’s income. Agencies also charge clientsfor the...

• 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...

• 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...

• 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...

• which became a seed.

  BEAUTIFUL ANDTRUE   Mom made spaghetti fordinner thatnight. Ronatewith us.Iasked himifhe was stillinterested inbuying meafive-piece drum setwith Zildjian cymbals. Hesaid, "Yeah. Ithink thatwould begreat." "Howabout adouble basspedal?" "Idon't know whatthatis,but Ibet wecould arrange it."Iasked himwhy hedidn't havehisown family. Momsaid,"Oskar!" I said, " What? " Ron putdown hisknife andfork andsaid, "It'sOK." Hesaid, "Idid have afamily, Oskar.Ihad awife anda daughter." "Didyougetdivorced?" Helau...

• Excerpt from The Old Curiosity Shop - anthology.

  'Well!' muttered Quilp, as he marked her earnest look. 'I believe you. Humph! Gone already? Gone in four-and-twenty hours I What the devil has he done with it,that's the mystery!' This reflection set him scratching his head and biting his nails once more. While he was thus employed his features gradually relaxed into what was with him acheerful smile, but which in any other man would have been a ghastly grin of pain, and when the child looked up again she found that he was regarding her with...

• Excerpt from Persuasion - anthology.

  “Yes, dear ma'am,” said Mrs. Croft, “or an uncertain engagement, an engagement which may be long. To begin without knowing that at such a time there will be themeans of marrying, I hold to be very unsafe and unwise, and what I think all parents should prevent as far as they can.” Anne found an unexpected interest here. She felt its application to herself, felt it in a nervous thrill all over her; and at the same moment that her eyes instinctivelyglanced towards the distant table, Captain Wen...

• 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...

• Excerpt from Our Mutual Friend - anthology.

  The Podsnaps lived in a shady angle adjoining Portman Square. They were a kind of people certain to dwell in the shade, wherever they dwelt. Miss Podsnap's lifehad been, from her first appearance on this planet, altogether of a shady order; for, Mr Podsnap's young person was likely to get little good out of association withother young persons, and had therefore been restricted to companionship with not very congenial older persons, and with massive furniture. Miss Podsnap's earlyviews of life be...

• 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...

• Confucian philosophy, Korean

  neglected by more traditional Confucianism. Read with new eyes, an entirely new level of meaning was uncovered in the ancient texts: they discovered a Confucian foundation for the meditative cultivation of consciousness that had been a particular strength of the Buddhists, and to frame it and provide an account of sagehood equal to Buddhist talk of enlightenment, they found a complete metaphysical system, a Confucian version of the kind of thinking that had been elaborated mainly under Daoist au...

• Swimming.

  the swimmer and the pinky finger should enter the water first. At the same time, the swimmer moves the left arm through the water below the left side of the body.Once in the water, the right arm begins pulling the swimmer forward by bending at the elbow. At the same time the swimmer holds the left arm straight as it reachesthe hip and lifts it out of the water. As the right arm continues to pull, the swimmer rotates slightly onto the right side and swings the left arm up above the head. As the s...