58 résultats pour "slow"
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Heart.
situation. A Cardiac Cycle Although the right and left halves of the heart are separate, they both contract in unison, producing a single heartbeat. The sequence of events from the beginning ofone heartbeat to the beginning of the next is called the cardiac cycle. The cardiac cycle has two phases: diastole, when the heart’s chambers are relaxed, and systole,when the chambers contract to move blood. During the systolic phase, the atria contract first, followed by contraction of the ventricles. T...
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Nova - astronomy.
When first discovered, the spectrum of a nova shows that the expanding layers of gas that cause the brightening have temperatures of 40,000° to 50,000° C (70,000°to 90,000° F)—about eight times as hot as the surface of the Sun. By the time a nova reaches maximum brightness, the temperature of the material has fallen to about10,000° C (about 20,000° F), or lower. Just after maximum brightness, the escaping cloud of gas cools and expands enough to become transparent. This transparency allows astro...
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Venus (planet) - astronomy.
level winds circle the planet at 360 km/h (225 mph), making a complete rotation in only four days. These winds are said to super-rotate because they travel muchfaster than the rotation of the planet itself. These high-speed winds cover the planet completely, blowing toward the west at virtually every latitude from equator topole. The motions of descending probes, however, have shown that the bulk of Venus’s tremendously dense atmosphere, closer to the planet’s surface, is almoststagnant. From th...
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Turtle.
Turtles use their jaws to cut and handle food. Instead of teeth, a turtle’s upper and lower jaws are covered by horny ridges, similar to a bird’s beak. Meat-eating turtlescommonly have knife-sharp ridges for slicing through their prey. Plant-eating turtles often have ridges with serrated edges that help them cut through tough plants.Turtles use their tongues in swallowing food, but unlike many other reptiles, such as chameleons, they cannot stick out their tongues to capture food. C Limb Structu...
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Turtle - biology.
Turtles use their jaws to cut and handle food. Instead of teeth, a turtle’s upper and lower jaws are covered by horny ridges, similar to a bird’s beak. Meat-eating turtlescommonly have knife-sharp ridges for slicing through their prey. Plant-eating turtles often have ridges with serrated edges that help them cut through tough plants.Turtles use their tongues in swallowing food, but unlike many other reptiles, such as chameleons, they cannot stick out their tongues to capture food. C Limb Structu...
- Sloth The sloth is a slow-moving mammal found in Central and South America.
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Ballet
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INTRODUCTION
Tchaikovsky's The Nutcracker
The Nutcracker is a classic ballet with music by Peter Ilyich Tchaikovsky.
Joffrey Ballet SchoolTraining for classical ballet dancers must begin when the students are very young. Here, teacher Dorothy Lister workswith her pre-ballet class of six-year-olds at the Joffrey Ballet School. These students are learning the five basic positions ofclassical ballet.Susan Kunklin/Photo Researchers, Inc. Different systems of ballet training have evolved, named after countries (Russia, France) or teachers (Italian dancer Enrico Cecchetti, Danish choreographer AugustBournonville). T...
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Hardware (computer).
Magnetic tape drives use magnetic tape similar to the tape used in VCR cassettes. Tape drives have a very slow read/write time, but have a very high capacity; in fact,their capacity is second only to hard disk drives. Tape drives are mainly used to back up data. Compact disc drives store information on pits burned into the surface of a disc of reflective material ( see CD-ROM). CD-ROMs can store up to 737 megabytes (MB) of data. A Compact Disc-Recordable (CD-R) or Compact Disc-ReWritable (CD-RW)...
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Encyclopedia of Philosophy: Adverbs
arguments to a predicate actually function as adverbial modifiers. Perhaps the best known account of this type isRoderick Chisholm's discussion of a certain class of statements about appearances. Chisholm suggests that a manwho ‘sees spots before his eyes' should be thought of as ‘sensing in a spotty manner' or as someone whom things‘appeared to spottily' ( 1957 ). This philosophical move is designed to rid the locution of any implication that in sensing spots before his eyes the man is...
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Gardening - biology.
of synthetic and organic fertilizers, see Organic Farming.) Fertilizers usually are sold in packages, on which the percentage by weight of the macronutrients nitrogen (N), phosphorus (P), and potassium (K) are listed on thelabel—always in the order N-P-K. For example, a fertilizer that is labeled 10-5-3 is 10 percent nitrogen, 5 percent phosphorus, and 3 percent potassium. V PLANTING AND TRANSPLANTING Before planting seeds, gardeners prepare, or till, the soil using a variety of methods. Some...
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Automobile Racing.
beginning in 1906 at Le Mans it came to refer to the principal F1 auto race in a given nation, except in the United States, where the term continues to be used lessdiscriminately. After the end of World War I in 1918, when automobile racing blossomed internationally, a series of GP races in several nations became reserved for F1competition, and an annual GP calendar was developed consisting of national races, such as the French Grand Prix and the British Grand Prix. An annual award calledthe Wor...
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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...
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Jupiter (planet) - astronomy.
Beneath the supercritical fluid zone, the pressure reaches 3 million Earth atmospheres. At this depth, the atoms collide so frequently and violently that the hydrogenatoms are ionized—that is, the negatively charged electrons are stripped away from the positively charged protons of the hydrogen nuclei. This ionization results in asea of electrically charged particles that resembles a liquid metal and gives rise to Jupiter’s magnetic field. This liquid metallic hydrogen zone is 30,000 to 40,000 k...
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Insect - biology.
they almost always have six legs. In some insects, such as beetles, the legs are practically identical, but in other insects each pair is a slightly different shape. Still otherinsects have specialized leg structures. Examples are praying mantises, which have grasping and stabbing forelegs armed with lethal spines, and grasshoppers andfleas, which have large, muscular hind legs that catapult them into the air. Mole crickets’ front legs are modified for digging, and backswimmers have hind legs de...
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Ludwig van Beethoven
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INTRODUCTION
Ludwig van Beethoven (1770-1827), German composer, considered one of the greatest musicians of all time.
dedication after learning that Napoleon had taken the title of emperor. Beethoven’s other instrumental works from the period of the Eroica also tend to expand the formal framework that he inherited from Haydn and Mozart. The Piano Sonata in C major op. 53 ( Waldstein ) and the Piano Sonata in F minor op. 57 ( Appassionata ), completed in 1804 and 1805 respectively, each employ bold contrasts in harmony, and they use a broadened formal plan, in which the meditative slow movements flow directly...
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Ludwig van Beethoven.
dedication after learning that Napoleon had taken the title of emperor. Beethoven’s other instrumental works from the period of the Eroica also tend to expand the formal framework that he inherited from Haydn and Mozart. The Piano Sonata in C major op. 53 ( Waldstein ) and the Piano Sonata in F minor op. 57 ( Appassionata ), completed in 1804 and 1805 respectively, each employ bold contrasts in harmony, and they use a broadened formal plan, in which the meditative slow movements flow directly...
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Ludwig van Beethoven
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INTRODUCTION
Ludwig van Beethoven
Ludwig van Beethoven is considered possibly the greatest Western composer of all time.
the other hand, breaks up the opening theme into contrasting segments in different tempi, whereas customary practice called for stating the theme in its entirety at thebeginning of a movement. In the first movement of the Eroica Symphony, one of the major works from Beethoven’s middle period, he again sought ways to expand upon the prevailing musical forms. At that time, composers usually organized movements in three major parts. First, the exposition introduces the musical themes of the pie...
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Acquired Immunodeficiency Syndrome.
child transmission is particularly prevalent in Africa. D Misperceptions About HIV Transmission The routes of HIV transmission are well documented by scientists, but health officials continually grapple with people’s unfounded fears concerning the potential for HIVtransmission by other means. HIV differs from other infectious viruses in that it dies quickly if exposed to the environment. No evidence has linked HIV transmission tocasual contact with an infected person, such as a handshake, huggi...
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Sun - astronomy.
A The Sun’s Place in the Milky Way The Milky Way Galaxy contains about 400 billion stars. All of these stars, and the gas and dust between them, are rotating about a galactic center. Stars that arefarther away from the center move at slower speeds and take longer to go around it. The Sun is located in the outer part of the galaxy, at a distance of 2.6 × 10 17 km (1.6 × 10 17 mi) from the center. The Sun, which is moving around the center at a velocity of 220 km/s (140 mi/s), takes 250 million y...
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Une histoire
- Tes mains sont douces, caresses moi doucement. Elle était passée du vouvoiement au tutoiement. Devant un tel appel je ne pus résister, et avec mes deux mains je lui caressais doucement les seins, et lui donnais un baiser dans le cou et derrière l'oreille, ce qui lui arracha un petit cri de plaisir. Ce moment délicieux fut vite interrompu, car d'autres promeneurs arrivaient près du bassin et nous décidâmes de revenir vers le bâtiment d'où venait la musique. En chemin, je m'excusais pour...
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Multiple Sclerosis.
slow the progress of the disease. It has become increasingly clear that early treatment is crucial to prevent or delay further damage to the nervous system. There are also treatments for specific symptoms, including corticosteroids (often taken intravenously), that can shorten the duration of an MS attack. Several drugs canrelieve spasticity, fatigue, and bladder problems. People with MS often find that nondrug treatments, such as regular exercise and adequate rest, can help them tomaintain more...
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Acid Rain.
the Adirondack Mountains of New York State, a quarter of the lakes and ponds are acidic, and many have lost their brook trout and other fish. In the middleAppalachian Mountains, over 1,300 streams are afflicted. All of Norway’s major rivers have been damaged by acid rain, severely reducing salmon and trout populations. E Plants and Animals The effects of acid rain on wildlife can be far-reaching. If a population of one plant or animal is adversely affected by acid rain, animals that feed on tha...
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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...
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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...
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Federal Reserve System.
and their powers were also expanded. For example, discount rates now had to be approved periodically by the board. Sales and purchases of governmentsecurities—the open-market operation that previously had been managed solely at the discretion of the presidents of the reserve banks—were centralized in the FederalOpen Market Committee (FOMC), consisting of the seven governors, the president of the Federal Reserve Bank of New York, and four other reserve bank presidentsserving on a rotating basis....
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Uruguay (country) - country.
Freedom of religion is guaranteed by the constitution of Uruguay. Three-quarters of the people belong to the Roman Catholic Church. There are also sizable Protestantand Jewish congregations. The official language is Spanish, which in Uruguay has been influenced by Italian vocabulary and pronunciation. C Education Uruguay has one of the highest rates of literacy in Latin America, at 98.2 percent of the adult population. Six years of primary education is compulsory, and Uruguay isone of the few n...
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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...
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Globalization.
higher living standard for their people. The World Bank made loans to developing countries for dams and other electrical-generating plants, harbor facilities, and otherlarge projects. These projects were intended to lower costs for private businesses and to attract investors. Beginning in 1968 the World Bank focused on low-cost loansfor health, education, and other basic needs of the world’s poor. B International Monetary Fund The IMF makes loans so that countries can maintain the value of thei...
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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...
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Arkansas - geography.
temperature rises to the upper 30°s C (lower 100°s F). C2 Precipitation Arkansas receives about 1,000 to 1,300 mm (about 40 to 50 in) of precipitation a year, and some areas receive even more. Most of the rain comes during winter andspring and at times is so heavy as to cause flooding. Snow is rare in the south but amounts to more than 250 mm (10 in) a year in the mountains. C3 Growing Season Arkansas has a long growing season. It averages 211 days for the state as a whole and ranges from 241...
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Arkansas - USA History.
temperature rises to the upper 30°s C (lower 100°s F). C2 Precipitation Arkansas receives about 1,000 to 1,300 mm (about 40 to 50 in) of precipitation a year, and some areas receive even more. Most of the rain comes during winter andspring and at times is so heavy as to cause flooding. Snow is rare in the south but amounts to more than 250 mm (10 in) a year in the mountains. C3 Growing Season Arkansas has a long growing season. It averages 211 days for the state as a whole and ranges from 241...
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Intelligence.
education. Teachers had no way of knowing which of the “slow” students had true learning problems and which simply had behavioral problems or poor prior education.In 1904 the French Ministry of Public Instruction asked Binet and others to develop a method to objectively identify children who would have difficulty with formaleducation. Objectivity was important so that conclusions about a child’s potential for learning would not be influenced by any biases of the examiner. The governmenthoped tha...
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Snorkeling.
injury from animals is to be aware of diving conditions at a site, to dive with a buddy, and to leave the water promptly should a problem occur. Boaters can also pose a serious threat to snorkelers. If not near a boat or a visible dive flag, snorkelers can be virtually invisible to boaters and can be run over.Another common danger in snorkeling is fatigue, which can lead to drowning. V WORKING UNDERWATER Most underwater work is accomplished by scuba divers because they can remain underwater at...
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Bob Dylan - Musik.
To RamonaMy Back PagesIt ain't Me Babe 1965 Bringing It All Back Home/Subterranean HomesickBlues Subterranean Homesick BluesMaggie's FarmLove Minus Zero/No LimitMr. Tambourine ManIt's Alright, Ma (I'm Only Bleeding)It's All Over Now, Baby Blue 1965 Highway 61 Revisited Like a Rolling StoneTombstone BluesIt Takes a Lot to Laugh, It Takes aTrain to CryHighway 61 RevisitedJust Like Tom Thumb's BluesDesolation Row 1966 Blonde on Blonde Rainy Day Women #12 & 35One of Us Must Know (Sooner orLater)I W...
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Virus (computer).
how closely it resembles a virus. It relies on experience with previous viruses to predict the likelihood that a suspicious file is an as-yet unidentified or unclassified newvirus. Other types of antiviral software include monitoring software and integrity-shell software. Monitoring software is different from scanning software. It detects illegal orpotentially damaging viral activities such as overwriting computer files or reformatting the computer's hard drive. Integrity-shell software establis...
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Kolkata - geography.
area, and trains have north-south lines with a few east-west connections. There are two major train terminals: Sealdah in the east central part of Kolkata and Hāoraacross the river from the Central Business District. Electric trams operate in Kolkata proper. The aging buses, trains, and tram cars suffer from overloading, creatinguncomfortable rides. Subway construction started in 1972 and became operational with 7 km (4.3 mi) of line in 1984. By 1995 all of the subway’s 16.4-km (10.2-mi)route fr...
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Electric Motors and Generators.
the armature. It is often desirable to generate as high a voltage as possible, and rotating armatures are not practical in such applications because of the possibility of sparkingbetween brushes and slip rings and the danger of mechanical failures that might cause short circuits. Alternators are therefore constructed with a stationary armaturewithin which revolves a rotor composed of a number of field magnets. The principle of operation is exactly the same as that of the AC generator described,...
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Immune System.
The humoral immune response involves a complex series of events after antigens enter the body. First, macrophages take up some of the antigen and attach it to classII MHC molecules, which then present the antigen to T helper cells. The T helper cells bind the presented antigen, which stimulates the T helper cells to divide andsecrete stimulatory molecules called interleukins. The interleukins in turn activate any B lymphocytes that have also bound the antigen. The activated B cells then divide...
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Coral - biology.
Soft corals lack a distinct skeleton. Although they live in colonies, the individual polyps are fused into a complex body, usually strengthened by small lumps or spikesknown as sclerites, which are made of protein and calcite. Soft corals come in a variety of shapes, including undulating sheets, upright mushroomlike shapes, andbeautiful shapes that form branches. A number of other octocorals have skeletons made from a hard or horny protein, sometimes strengthened with more brittle calcareous dep...
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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...
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Nuclear Energy
I
INTRODUCTION
Gundremmingen Nuclear Power Plant, Germany
The first of three boiling-water nuclear reactors at Germany's Gundremmingen plant began operating in 1966 but was
permanently shut down after being decommissioned in 1983.
such as ¯U is induced by the absorption of a neutron as in producing cesium-140, rubidium-93, three neutrons, and 200 MeV, or 3.2 × 10 -11 J (7.7 × 10 -12 cal). A nuclear fission reaction releases 10 million times as much energy as is released in a typical chemical reaction. See Nuclear Chemistry. III NUCLEAR ENERGY FROM FISSION The two key characteristics of nuclear fission important for the practical release of nuclear energy are both evident in equation (2). First, the energy per fiss...
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Artificial Satellite - astronomy.
The first stage of a multistage rocket consists of rocket engines that provide a huge amount of force, or thrust. The first stage lifts the entire launch vehicle—with itsload of fuel, the rocket body, and the satellite—off the launch pad and into the first part of the flight. After its engines use all their fuel, the first stage portion of therocket separates from the rest of the launch vehicle and falls to Earth. The second stage then ignites, providing the energy necessary to lift the satellit...
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Gravitation
I
INTRODUCTION
Gravitation, the force of attraction between all objects that tends to pull them toward one another.
precise observations possible, and Galileo was one of the first to use a telescope to study astronomy. In 1609 Galileo observed that moons orbited the planet Jupiter, afact that could not reasonably fit into an earth-centered model of the heavens. The new heliocentric theory changed scientists' views about the earth's place in the universe and opened the way for new ideas about the forces behind planetarymotion. However, it was not until the late 17th century that Isaac Newton developed a theory...
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Gravitation - astronomy.
precise observations possible, and Galileo was one of the first to use a telescope to study astronomy. In 1609 Galileo observed that moons orbited the planet Jupiter, afact that could not reasonably fit into an earth-centered model of the heavens. The new heliocentric theory changed scientists' views about the earth's place in the universe and opened the way for new ideas about the forces behind planetarymotion. However, it was not until the late 17th century that Isaac Newton developed a theory...
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Internet.
usually pays a fixed monthly fee for a dedicated connection. In exchange, the company providing the connection agrees to relay data between the user’s computer andthe Internet. Dial-up is the least expensive access technology, but it is also the least convenient. To use dial-up access, a subscriber must have a telephone modem, a device thatconnects a computer to the telephone system and is capable of converting data into sounds and sounds back into data. The user’s ISP provides software that con...
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Dinosaur - biology.
The behavior of dinosaurs was governed by their metabolism and by their central nervous system. The dinosaurs’ metabolism—the internal activities that supply thebody’s energy needs—affected their activity level. It is unclear whether dinosaurs were purely endothermic (warm-blooded), like modern mammals, or ectothermic (cold-blooded), like modern reptiles. Endotherms regulate their body temperature internally by means of their metabolism, rather than by using the temperature oftheir surroundin...
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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...
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Montana - geography.
(191 sq mi), is Montana’s largest lake, and the largest natural freshwater lake in the contiguous states west of the Mississippi River. C Climate Climatic regions in Montana coincide roughly with the two major physiographic regions. In western Montana, as compared with the eastern plains area, winters tend tobe milder while summers are cooler. Precipitation is more evenly distributed throughout the year in the west, and it is cloudier and somewhat more humid in all seasons.In addition, the grow...
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Montana - USA History.
(191 sq mi), is Montana’s largest lake, and the largest natural freshwater lake in the contiguous states west of the Mississippi River. C Climate Climatic regions in Montana coincide roughly with the two major physiographic regions. In western Montana, as compared with the eastern plains area, winters tend tobe milder while summers are cooler. Precipitation is more evenly distributed throughout the year in the west, and it is cloudier and somewhat more humid in all seasons.In addition, the grow...
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New York (city) - geography.
The Bronx is the fourth largest and the northernmost of the five boroughs, and the only one on the American mainland. Even so, it is surrounded by water on threesides: Long Island Sound on the east, the Harlem and East rivers on the south, and Hudson River on the west. Encompassing 109 sq km (42 sq mi), it had 1,332,650inhabitants in 2000. Largely residential, the Bronx includes dozens of vibrant neighborhoods. Fieldston is particularly elegant, with great stone houses set among spacious lawns a...