588 résultats pour "maker"

• Comparative Anatomy.

  In comparing two species, anatomists have to be careful to differentiate between homologous structures, which are ones that have evolved from a shared ancestor, andanalogous structures, which have developed from different origins. Homologous structures are built on the same underlying plan. A human arm, a bat’s wing, and awhale’s flipper look quite different from the outside, but the bones inside reveal that these limbs all have the same basic structure. Analogous structures, by contrast,often l...

• 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...

• United States Government.

  Article II establishes an executive department headed by a president and vice president. The article further describes the powers of the offices, the manner of election,and the qualifications for office. Of special significance is the president’s constitutional role as commander of the nation’s armed forces, which assures civilian controlover the military. Because the president is the head of the armed forces and only Congress can declare war, the authority of the military is diffused and its po...

• Louisiana - geography.

  lakes are on the Red River and its tributaries. In addition, small oxbow lakes are numerous in the Mississippi Alluvial Plain. Oxbow lakes are formed when a river cutsthrough the neck of one of its loops, or meanders, thus establishing a shorter course and leaving the former loop as a lake separate from the river. Louisiana also hassome artificially created reservoirs. C Coastline Louisiana’s long and irregular coastline extends along the Gulf of Mexico from the Pearl River on the east to the S...

• Louisiana - USA History.

  lakes are on the Red River and its tributaries. In addition, small oxbow lakes are numerous in the Mississippi Alluvial Plain. Oxbow lakes are formed when a river cutsthrough the neck of one of its loops, or meanders, thus establishing a shorter course and leaving the former loop as a lake separate from the river. Louisiana also hassome artificially created reservoirs. C Coastline Louisiana’s long and irregular coastline extends along the Gulf of Mexico from the Pearl River on the east to the S...

• 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...

• Telescope - astronomy.

  Observatory). In some telescopes designed in the 1990s, the mirror’s weight has been dramatically reduced by sandwiching a honeycomb pattern of glass ribs between a thin, butrigid, concave mirror and a flat back plate. Engineers have even developed meniscus mirrors—mirrors that are too thin to support their own weight. An adjustableframework supports the meniscus mirror, and servomechanical actuators, controlled by computer, continually adjust the shape of the mirror as it tracks celestial tar...

• Bear - biology.

  programs sponsored by zoos or other breeding centers have attempted to breed giant pandas in captivity, although most of these programs have proved unsuccessful.Among the difficulties faced by captive breeders has been the problem of encouraging a female giant panda to mate with a selected male during the two to three daysof the year when she is most fertile, a period known as estrus. B Spectacled Bear Creamy-white rings surrounding the eyes give the spectacled bear its name. Its shaggy coat of...

• Mammal - biology.

  On land, mammals live in many different habitats, and at a wide range of altitudes. Many mammals dig burrows as refuges or as places to raise their young, but somehave developed a largely subterranean lifestyle, feeding on small animals or plant roots beneath the soil's surface. These animals, including moles and mole-rats, digthrough the ground either with spadelike front paws or with their teeth, and they detect danger by being highly sensitive to vibrations transmitted through the soil.Most m...

• Prints and Printmaking I INTRODUCTION Prints and Printmaking, pictorial images that can be inked onto paper, and the art of creating and reproducing them.

  Bewick’s The SkylarkBritish engraver Thomas Bewick’s The Skylark is part of his History of British Birds (2 vols., 1797 and 1804). Bewick wasthe first artist to demonstrate the full potential of wood engraving and is renowned for his fine natural history illustrations.Each illustration shows some of the bird’s natural habitat.Folio Society, London/Bridgeman Art Library, London/New York Historically, the wood engraving was chiefly used for illustrations in magazines and books. It is similar to th...

• Theater I INTRODUCTION The Art of Theater BBC Worldwide Americas, Inc.

  Theater at EpidaurusAncient Greek dramas were performed in open-air theaters like this one in Epidaurus, Greece, which was designed byPolyclitus the Younger in 350 bc. A festival of ancient Greek drama is still held in the summer in this 14,000-seat theater.Roger Wood/Corbis Fundamental to the theater experience is the act of seeing and being seen; in fact, the word theater comes from the Greek word theatron , meaning 'seeing place.' Throughout the history of world cultures, actors have used...

• Excerpt from Little Dorrit - anthology.

  'That,' said the turnkey, 'is agen her.' 'She is so little used to go out alone,' said the debtor, 'that I am at a loss to think how she will ever make her way here, if she walks.' 'P'raps,' quoth the turnkey, 'she'll take a ackney coach.' 'Perhaps.' The irresolute fingers went to the trembling lip. 'I hope she will. She may not think of it.' 'Or p'raps,' said the turnkey, offering his suggestions from the top of his well-worn wooden stool, as he might have offered them to a...

• Congress of the United States.

  senator, a person must be at least 30 years old, a citizen for nine years, and a resident of the state from which he or she is elected. Most members of Congress haveserved in state legislatures, city councils, or other elected bodies. See United States Senate: Campaigning for the Senate ; United States House of Representatives: Campaigning for the House. The 435 House seats are divided among the states in proportion to each state’s population. Every state is guaranteed at least one seat. State...

• Bat - biology.

  tomb bat has rather small ears. The shapes of bat ears are extremely varied. The wide ears of the Australian false vampire bat meet above the head and are fused.Many bats are able to turn their ears in the direction of faint noises. Bat hearing and its use in echolocation are highly developed. Some bats have large, conspicuous eyes, while others may have small beady eyes. This variation suggests that vision plays different roles in the lives of various species.Despite the familiar expression, 'b...

• Light - astronomy.

  Each different frequency or wavelength of visible light causes our eye to see a slightly different color. The longest wavelength we can see is deep red at about 700 nm.The shortest wavelength humans can detect is deep blue or violet at about 400 nm. Most light sources do not radiate monochromatic light. What we call white light,such as light from the Sun, is a mixture of all the colors in the visible spectrum, with some represented more strongly than others. Human eyes respond best to greenlight...

• Poker.

  After the ante and the initial deal, the first round of betting starts with the player to the left of the dealer. This bettor can check (make no bet), make a bet, or fold. To stay in the game, subsequent bettors must call (match the current bet) or raise (increase the total bet). A round of betting ends when no player makes a further bet or a set limit of turns around the table has been reached. In the next round of betting, the player to the left of the bettor that started the last round o...

• Trinidad and Tobago - country.

  III PEOPLE The history of Trinidad and Tobago is reflected in the makeup of its population, among the most ethnically diverse in the Caribbean. Blacks of African ancestry andAsians of Indian ancestry each make up about 40 percent of the population. The remainder is mainly of mixed ancestry, although there are also small groups of peopleof Chinese, European, South American, and Middle Eastern descent. The ethnic diversity of Trinidad and Tobago owes its origins to slavery and its abolition. Afr...

• Austria - country.

  Wildlife is generally scarce in Austria. Chamois, deer, and marmot are still present; bear, which were once abundant, are now almost completely absent. Hunting isstrictly regulated to protect the remaining species. F Environmental Issues Industrial emissions, a high volume of tourist traffic, and significant air pollution from other countries—principally the former East Germany, Slovakia, and the CzechRepublic—combine to make acid rain the major environmental problem in Austria. One-quarter of...

• Football.

  C Special Teams Each team has players who enter the game during special plays such as kickoffs, field goals, punts, and returns. The kicker kicks off at the beginning of a game or half,and after his team has scored. The kicker also scores points for the offensive team by kicking the ball through the goalpost’s vertical posts, also known as the uprights;these scores are called field goals. When the offensive team must surrender the ball to the opponents, a punter comes in to kick the ball downfi...

• 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...

• Monkeys.

  Female monkeys usually give birth to only one baby at a time. The baby stays with its mother while itfeeds on her milk. In many species, the females stay with their mother’s family group for life. Malesoften leave their mother’s family group when they grow up. Compared to other animals, monkeys live a long time. It’s hard to know how long a monkey in the wildwill live. But some monkeys in zoos have lived to be more than 50 years old. WHAT DO MONKEYS EAT? What a monkey eats depends on the size of...

• Nixon's Checkers Speech Under attack for having used a secret campaign fund for his personal expenses, Richard M.

  The first way is to be a rich man. I don't happen to be a rich man so I couldn't use that. Another way that is used is to put your wife on the payroll. Let me say, incidentally, my opponent, my opposite number for the Vice Presidency on the Democraticticket, does have his wife on the payroll. And has had her on his payroll for the ten years—the past ten years. Now just let me say this. That's his business and I'm not critical of him for doing that. You will have to pass judgment on that particul...

• Crafts.

  VI POTTERY Ceramic objects can be molded completely by hand or thrown (shaped) on a potter's wheel, a device with a rotating horizontal disk. When the clay hardens, it is fired ina high-temperature oven, or kiln, to strengthen it. To make the object waterproof, glazes may then be applied and the piece fired again. Although hand construction iseasy to master, throwing on the potter's wheel requires practice. Several simple tools are used by potters, including sponges, trimming tools, wooden sha...

• Digestive System.

  The stomach, located in the upper abdomen just below the diaphragm, is a saclike structure with strong, muscular walls. The stomach can expand significantly to storeall the food from a meal for both mechanical and chemical processing. The stomach contracts about three times per minute, churning the food and mixing it with gastricjuice. This fluid, secreted by thousands of gastric glands in the lining of the stomach, consists of water, hydrochloric acid, an enzyme called pepsin, and mucin (the...

• From The Scarlet Letter - anthology.

  “Mercy on us, goodwife,” exclaimed a man in the crowd, “is there no virtue in woman, save what springs from a wholesome fear of the gallows? That is the hardestword yet! Hush, now, gossips; for the lock is turning in the prison-door, and here comes Mistress Prynne herself.” The door of the jail being flung open from within, there appeared, in the first place, like a black shadow emerging into the sunshine, the grim and grisly presence ofthe town-beadle, with a sword by his side and his staff...

• 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,...

• Computer Memory.

  been created, information can be retrieved but not changed. Newer technologies allow ROMs to be semi-permanent—that is, the information can be changed, but ittakes several seconds to make the change. For example, a FLASH memory acts like a ROM because values remain stored in memory, but the values can be changed. C External Memory External memory can generally be classified as either magnetic or optical, or a combination called magneto-optical. A magnetic storage device, such as a computer'shar...

• Aztec Empire.

  tribute to the empire in agricultural products, which were used to finance public projects. All able-bodied men owed military service to the empire. Citizens could also bedrafted to work on public lands or build temples, dikes, aqueducts, and roads. Although Aztec society had strict classes, a person’s status could change based on his or her contribution to society. Commoners could improve their rank, especially byperforming well in battle, and become prosperous landowners. Young people of some...

• Aztec Empire - USA History.

  tribute to the empire in agricultural products, which were used to finance public projects. All able-bodied men owed military service to the empire. Citizens could also bedrafted to work on public lands or build temples, dikes, aqueducts, and roads. Although Aztec society had strict classes, a person’s status could change based on his or her contribution to society. Commoners could improve their rank, especially byperforming well in battle, and become prosperous landowners. Young people of some...

• Marketing.

  Where advertising reaches a mass audience, personal or direct selling focuses on one customer at a time. That kind of individual attention makes direct sellingexpensive, but it also makes it effective. As the costs of personal selling have risen, the utilization of salespeople has changed. Simple transactions are completed byclerks. Salespeople are now used primarily where the products are complex and require detailed explanation, customized application, or careful negotiation over priceand paym...

• Skin. I INTRODUCTION Skin, outer body covering of an animal. The term skin

  III SKIN APPENDAGES In humans, the skin appendages, or structures embedded in the skin, include hair, nails, and several types of glands. Glands are groups of cells that produce andsecrete substances needed by other parts of the body. In other vertebrates, the skin appendages include scales (in fish and reptiles) and feathers (in birds). Together,the skin and the skin appendages are known as the integumentary system of the body. A Hair Hair is a distinguishing characteristic of mammals, a gro...

• Criminal Procedure.

  B State Criminal Procedure A person prosecuted in the courts of a particular state on a charge of violating the criminal laws of that state is subject to state criminal procedure. State criminalprocedure is found in the constitution, statutes, rules, and judicial decisions of that state. Furthermore, portions of the U.S. Constitution are applicable to state criminaldefendants. State constitutions generally guarantee a state criminal defendant most of the same rights that a federal defendant is...

• Supreme Court of Canada.

  whether the leave to appeal will be granted and the case heard by the Court. The Court has no specified criteria by which it determines whether to grant leave, and the Court does not give reasons for its decision. The key factor appears to be acase’s degree of national importance. Other factors might include the impact of uncertainty in the challenged law, the case’s appropriateness for developing the law torespond to changing social needs, and the presence of a split decision at the court of ap...

• Laos - country.

  by the year 2025. About one-quarter of Laos’s people live in mountainous regions. The rest live in upland valleys or on the flood plains of the Mekong and its tributaries.Just over three-quarters of the population live in rural areas, although the proportion of people living in urban areas is steadily increasing. Vientiane is the capital and largest city of Laos. Louangphrabang, the former royal capital, is an increasingly popular tourist destination. Other major cities are theregional capitals...

• Ukraine - country.

  a major hazard, especially to Ukraine’s water supply. The Chernobyl’ complex was finally shut down completely in December 2000, with the financial assistance ofWestern nations. The funds were to pay for the completion of two other nuclear power plants that would produce enough power to make up for the loss of the powersupply from the Chernobyl’ plant. III PEOPLE OF UKRAINE The population of Ukraine was estimated in 2008 at 45,994,287, giving the country a population density of 76 persons per s...

• 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...

• how shakspear can make me funny

• The Scarlett letter

  The Scarlet Letter is an american romantic novel of fiction, written by Nathaniel Hawthorne, published in the mid-nineteenth century. It is considered to be his best work. Nathaniel Hawthorne was an American novelist and short story writer from the nineteen century. He is a dark romantic (anti-transcendentalist) which means that he explores the psychological effects of guilt and sin, madness, derangement in the human psyche. The Scarlett letter is marked by this exploration. The st...

• Monkey (animal) - biology.

  traveling in troops, often take turns acting as sentinel, making specific alarm calls to alert their companions to approaching danger. In trees, monkeys have other waysof outwitting their enemies. Capuchins, for example, sometimes fend off inquisitive predators by urinating on them from high above or by jumping up and down tomake dead branches fall on the predators. Most monkeys can breed at any time of the year, so their troops often contain young of many different ages. Courtship is typically...

• Molecule - chemistry.

  attracted to the negatively charged electrons between them. The electrons belong to the molecule as a whole. However, each hydrogen atom now has a complete outershell of two electrons. The formula H 2 describes a hydrogen molecule, a discrete unit. When a molecule contains just two atoms, such as the hydrogen molecule does, it is called a diatomic molecule. Some atoms can form covalent bonds with more than one other atom and thus create a larger molecule. Atoms form molecules with covalent bo...

• Excerpt from A Midsummer Night's Dream - anthology.

  BOTTOM: Well, proceed. QUINCE: Robin Starveling, the tailor? STARVELING: Here, Peter Quince. QUINCE: Robin Starveling, you must play Thisbe’s mother. Tom Snout, the tinker? SNOUT: Here, Peter Quince. QUINCE: You, Pyramus’ father; myself, Thisbe’s father; Snug, the joiner, you the lion’s part; and I hope here is a play fitted. SNUG: Have you the lion’s part written? Pray you, if it be, give it me; for I am slow of study. QUINCE: You may do it extempore; for it is nothing but roaring. BOTTOM: Let...

• Camping.

  Commercial campgrounds serve as campsites for RV and car campers on the outskirts of national and state parks and along highways throughout North America.Owners of commercial campgrounds charge campers on a daily or weekly basis, and provide campsites equipped with hookups for electricity and water. They may alsoprovide such amenities as showers, laundry facilities, or a swimming pool. Many commercial campgrounds belong to a club or network that allows its members toreserve campsites in advance....

• Gambling.

  C Lotteries Lotteries are another form of gambling. In a lottery, tickets are sold for a set amount and a share of the proceeds is returned to the winners, usually through a randomdraw. Most games allow players to pick their own numbers or let a computer randomly pick for them. Lotteries offer a wide variety of games, including weekly drawings,instant “scratch” tickets, daily games, and superlottos with prizes increasing until there is a winner. Large lottery prizes sometimes exceed $100 millio...

• Milwaukee - geography.

  acts ranging from alternative rock to country music. During the rest of the summer months, the park is the site of weekend festivals staged by Milwaukee’s majorethnic groups: Italian, Irish, German, African American, Polish, Mexican, Native American, and Asian. The Great Circus Parade, featuring the world’s largest collection ofornate circus wagons, is another staple of Milwaukee’s festival season. The Wisconsin State Fair is held annually in nearby West Allis. V RECREATION The largest single u...

• Neandertals.

  Neandertals made stone tools by striking flakes from rock “cores.” The cores were carefully selected and prepared so that only a single blow was normally required todetach a flake. A number of relatively standardized flakes were sometimes produced from a single core. These sharp flakes served as “blanks” that were further workedand shaped into the desired tools. Suitable stone was sometimes rare, and often tools were sharpened and resharpened to make new tools, yielding a whole variety ofshapes...

• 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...

• From "Resistance to Civil Government" - anthology.

  intending it, as God. A very few—as heroes, patriots, martyrs, reformers in the great sense, and men—serve the state with their consciences also, and so necessarily resist it for the most part; and they are commonly treated as enemies by it. A wise man will only be useful as a man, and will not submit to be “clay,” and “stop a holeto keep the wind away,” but leave that office to his dust at least: “I am too high born to be propertied,To be a second at control,Or useful serving-man and instr...

• Georgia (country) - country.

  1917. During the subsequent Soviet period, religious practice was strongly discouraged because the Soviet state was officially atheistic; however, the GeorgianOrthodox Church was allowed to function openly. Orthodox Christianity is the religion of about 58 percent of the Georgian population. Muslims represent about 19 percent of the country’s population, with ethnicAzerbaijanis, Kurds, and Ajars comprising the principal Muslim groups. Ajars are ethnic Georgians who converted to Islam in the 17th...

• Health Insurance.

  needs services. Essentially, individuals make regular payments to the plan rather than having to pay especially large sums at any one time in the event of sudden illnessor injury. In this way, the group as a whole funds expensive treatments for those few who need them. Many people believe that in addition to providing financial stability, health insurance can promote good health. Supporters of this idea claim that by lowering thepersonal cost of services, insurance induces individuals to seek he...

• History of Astronomy - astronomy.

  Egypt, the Sun was directly overhead at noon. On the same date and time in Alexandria, Egypt, the Sun was about 7 degrees south of zenith. With simple geometryand knowledge of the distance between the two cities, he estimated the circumference of the Earth to be 250,000 stadia. (The stadium was a unit of length, derivedfrom the length of the racetrack in an ancient Greek stadium. We have an approximate idea of how big an ancient Greek stadium was, and based on that approximationEratosthenes was...