182 résultats pour "shower"

• Human Evolution.

  Strepsirhines are the most primitive types of living primates. The last common ancestors of strepsirhines and other mammals—creatures similar to tree shrews andclassified as Plesiadapiformes—evolved at least 65 million years ago. The earliest primates evolved by about 55 million years ago, and fossil species similar to lemursevolved during the Eocene Epoch (about 55 million to 38 million years ago). Strepsirhines share all of the basic characteristics of primates, although their brains are notpa...

• Human Evolution - biology.

  classified as Plesiadapiformes—evolved at least 65 million years ago. The earliest primates evolved by about 55 million years ago, and fossil species similar to lemursevolved during the Eocene Epoch (about 55 million to 38 million years ago). Strepsirhines share all of the basic characteristics of primates, although their brains are notparticularly large or complex and they have a more elaborate and sensitive olfactory system (sense of smell) than do other primates. B Haplorhines B1 Tarsiers T...

• Alzheimer's Disease.

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

• Sleep - biology.

  V FUNCTIONS OF SLEEP Although no one knows for sure why we sleep, there are a number of theories. Sleep may have evolved to protect animals from their predators by reducing theiractivity during the times when they are most vulnerable. Research has shown that REM and NREM sleep may serve specific biological functions. Sleep deprivation studies reveal that humans and other animals respond to sleeploss in the same way. When study subjects are deprived of REM sleep, they tend to spend longer period...

• Interstellar Matter - astronomy.

  silhouette of a cloud of dust. At other times, it blocks only a percentage of the light from behind it, a process known by astronomers as extinction . The long, narrow dark lanes in the Milky Way as seen from Earth are examples of extinction. The amount of extinction is different for different wavelengths of light. A2 Reddening Starlight that does not get completely absorbed by interstellar dust can still be changed by the dust’s effects. As light passes through less dense patches of interstel...

• 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...

• Natural Satellite - astronomy.

  Titan, Saturn’s largest moon, also has few impact craters. Although icy volcanism from water and ammonia may occur along with some tectonic activity, Titan’s youngsurface is most likely the result of weather processes. Titan’s dense, cold atmosphere precipitates particles of complex organic molecules that accumulate as dunes andmountains. Methane rain erodes the surface and creates lakes at the moon’s poles. Triton’s young surface also may result from processes in its atmosphere, as well aserupt...

• Mark Twain.

  father, who keeps him prisoner in an isolated cabin. The boy escapes and, together with a runaway slave, Jim, sails down the Mississippi on a raft. During their trip,Huck and Jim encounter many unusual characters, including two families involved in a senseless feud and a pair of scoundrels who swindle innocent townspeople. Theirexperiences bring about a strong friendship between the boy and the slave, but their adventures end when Jim is captured and held at the farm of Tom Sawyer’s AuntSally. W...

• Mark Twain I INTRODUCTION Mark Twain, pseudonym of Samuel Langhorne Clemens (1835-1910), American writer and humorist, whose best work is characterized by broad, often irreverent humor or biting social satire.

  father, who keeps him prisoner in an isolated cabin. The boy escapes and, together with a runaway slave, Jim, sails down the Mississippi on a raft. During their trip,Huck and Jim encounter many unusual characters, including two families involved in a senseless feud and a pair of scoundrels who swindle innocent townspeople. Theirexperiences bring about a strong friendship between the boy and the slave, but their adventures end when Jim is captured and held at the farm of Tom Sawyer’s AuntSally. W...

• Mark Twain - USA History.

  father, who keeps him prisoner in an isolated cabin. The boy escapes and, together with a runaway slave, Jim, sails down the Mississippi on a raft. During their trip,Huck and Jim encounter many unusual characters, including two families involved in a senseless feud and a pair of scoundrels who swindle innocent townspeople. Theirexperiences bring about a strong friendship between the boy and the slave, but their adventures end when Jim is captured and held at the farm of Tom Sawyer’s AuntSally. W...

• Lifehack

• Byzantine Art and Architecture I INTRODUCTION Archangel Michael This depiction of the archangel Michael, in Saint Mark's Cathedral in Venice, Italy, is an example of ancient enamel art.

  This Byzantine ivory relief shows Christ the Pantocrator, or ruler of the world, raising his hand in a gesture of blessing. Itcomes from the cover of a lectionary, or book containing portions of the scriptures, and dates from the second golden ageof Byzantine art, the late 10th century. The relief is in the Fitzwilliam Museum, Cambridge, England.Bridgeman Art Library, London/New York Mosaics were the favored medium for the interior adornment of Byzantine churches. The small cubes, or tesserae, t...

• Rap I INTRODUCTION Jay-Z Rapper Jay-Z rose to popularity with such albums as Vol.

  Run-DMCTypically in rap music, vocalists recite rhyming lyrics in time to a beat that may be sampled from prerecorded music byother groups. Black youths developed rap music on the streets of inner cities in the United States during the 1970s, butthe style has expanded to include a wider variety of performers and audiences. The rap group Run-DMC, shown here, wasa powerful early influence in the genre. The group helped bring rap music into the mainstream when it released “WalkThis Way” (1986), a s...

• Statistics I INTRODUCTION Statistics, branch of mathematics that deals with the collection, organization, and analysis of numerical data and with such problems as experiment design and decision making.

  Professional pollsters typically conduct their surveys among sample populations of 1,000 people. Statistical measurementsshow that reductions in the margin of error flatten out considerably after the sample size reaches 1,000.© Microsoft Corporation. All Rights Reserved. The raw materials of statistics are sets of numbers obtained from enumerations or measurements. In collecting statistical data, adequate precautions must be taken tosecure complete and accurate information. The first problem of...

• Coronary Heart Disease.

  when a patient is at rest may indicate that the blood supply of the heart is not normal, and the ECG can often detect damage from a previous heart attack. In anexercise stress test, an ECG is recorded while a patient is performing physical activity such as walking on a treadmill or riding a stationary bicycle. As the intensity ofexercise increases, the doctor looks for specific changes in the ECG that indicate the heart is not getting enough oxygen. In cardiac catheterization, a long, thin, flex...

• Wolfgang Amadeus Mozart I INTRODUCTION Wolfgang Amadeus Mozart Wolfgang Amadeus Mozart, an 18th-century Austrian classical composer and one of the most famous musicians of all time, came from a family of musicians that included his father and sister.

  The opera, Mitridati, rè di Ponto (Mithridates, King of Pontus), was produced in 1770 in Milan under Mozart’s direction with success. Also that year the pope made Mozart a knight of the Order of the Golden Spur. A Salzburg and Germany From 1775 to 1780 Mozart was based mainly in Salzburg working for the archbishop Hieronymous von Colloredo. Although dissatisfied with the low pay and limitedopportunities his employment offered, Mozart composed many works during this period, including his first...

• Solar System - astronomy.

  dwarf planets according to the IAU because they have rounded shapes from their own gravity but have not cleared their neighborhoods in space of other objects—bothorbit through the Kuiper Belt, a region beyond Neptune containing thousands of small icy bodies. Pluto and Eris are composed of layers of ice around a rocky core.Ceres qualifies as a dwarf planet because it is spherical but is found in the asteroid belt, a zone between the orbits of Mars and Jupiter that contains thousands of smallrocky...

• Heredity - biology.

  allele from the mother and a mutated allele from the father. In both of these cases, the child will be a carrier. The child develops the disease only if he or she receives amutated allele from each parent. When both parents are carriers, there is a 25 percent chance that a child will be disease-free, a 25 percent chance that it will have thedisease, and a 50 percent chance that it will be a carrier. Examples of genetic diseases that follow the dominant-recessive pattern include sickle-cell anemi...

• Disputed Presidential Election of 2000 - U.

  counts. At oral arguments on November 20, the justices seemed to be most interested in one issue: At what point did allowing re-counts risk making Florida too late toparticipate in the electoral college vote? Gore’s lawyers, led by David Boies, argued that the state had until December 12 to pick its electors, which allowed plenty oftime for the re-counts. Electors from each state would meet on December 18 to cast their votes. The next day the court ruled unanimously for Gore and granted a five-d...

• Amphibian (animal) - biology.

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

• Sexual Harassment.

  A person who believes he or she has experienced sexual harassment on the job has a limited period of time in which to file a complaint with the EEOC. After the EEOCinvestigates the matter, it issues a right to sue letter, regardless of its conclusions about the matter. The victim then has 90 days to file a lawsuit against the employer in federal court. If he or she is successful in the lawsuit, the victim can receive up to $300,000 in compensatory damages for each incident of unlawful harassme...

• Radar.

  gathers the weak returning radar signals and converts them into an electric current. Because a radar antenna may both transmit and receive signals, the duplexerdetermines whether the antenna is connected to the receiver or the transmitter. The receiver determines whether the signal should be reported and often does furtheranalysis before sending the results to the display. The display conveys the results to the human operator through a visual display or an audible signal. B1 The Antenna The rec...

• Television.

  A charge-coupled device (CCD) can be much smaller than a camera tube and is much more durable. As a result, cameras with CCDs are more compact and portablethan those using a camera tube. The image they create is less vulnerable to distortion and is therefore clearer. In a CCD, the light from a scene strikes an array ofphotodiodes arranged on a silicon chip. Photodiodes are devices that conduct electricity when they are struck by light; they send this electricity to tiny capacitors. Thecapacitors...

• Midnighters

• 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....

• On the road

• Afghanistan - country.

  D Climate Most of Afghanistan has a subarctic mountain climate with dry and cold winters, except for the lowlands, which have arid and semiarid climates. In the mountains and afew of the valleys bordering Pakistan, a fringe effect of the Indian monsoon, coming usually from the southeast, brings moist maritime tropical air in summer.Afghanistan has clearly defined seasons: Summers are hot and winters can be bitterly cold. Summer temperatures as high as 49°C (120°F) have been recorded in thenorth...

• Astronomy - astronomy.

  Telescopes may use either lenses or mirrors to gather visible light, permitting direct observation or photographic recording of distant objects. Those that use lenses arecalled refracting telescopes, since they use the property of refraction, or bending, of light ( see Optics: Reflection and Refraction ). The largest refracting telescope is the 40-in (1-m) telescope at the Yerkes Observatory in Williams Bay, Wisconsin, founded in the late 19th century. Lenses bend different colors of light by d...

• Alaska - geography.

  depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...

• Alaska - USA History.

  depression surrounded by highlands and have the coldest winter and hottest summer temperatures in Alaska. Once the Kuskokwim River passes through theKuskokwim Mountains, it forms the southern edge of a vast lake-studded alluvial plain bounded on the north by the Yukon River. This water-logged lowland is a majorsummer nesting area for birds. Fairbanks is the major city in this region, while Fort Yukon is the major community in the Yukon Flats and Bethel the largest settlementon the Lower Kuskokwi...

• Library (institution).

  rooms, special galleries for exhibitions, auditoriums for lectures or concerts, computer rooms, children’s rooms, photocopy rooms, and classrooms. A3 Lending Materials As part of their mission to provide information resources to the community, public libraries allow users to borrow items from their collections for limited amounts of time.To be eligible to borrow public library materials, a user must register her or his name, address, and other basic information with the local library’s circulat...

• The Alchimist