59 résultats pour "devices"
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Electronic Music
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INTRODUCTION
Electronic Music, music that requires the use of electronic devices to produce or manipulate sound during its composition and performance.
III SYNTHESIZERS AND OTHER ELECTRONIC TECHNOLOGY Moog SynthesizerThe musical synthesizer was invented by American Robert Moog. Soon after Moog introduced an early version in 1964, itbecame known as the “Moog Synthesizer,” and then simply as the “Moog.” Here, Japanese composer Isao Tomita uses aMoog synthesizer in his studio.Huynh Cong/AP/Wide World Photos In the 1950s sound synthesizers were developed, principally in the United States. Synthesizers enabled composers to produce sounds electroni...
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Machine
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INTRODUCTION
Machine, simple device that affects the force, or effort, needed to do a certain amount of work.
to decrease the amount of force needed to do work or to change the direction of the force. The wheel and axle and some levers can also be used to increase the speedof performance of a task, but doing so always increases the amount of force needed. A Inclined Plane NutsNuts are pieces of metal with a hole in the middle. They are screwed on the end of a bolt as a fastening. Nuts come invarying shapes, depending on their intended use.© Microsoft Corporation. All Rights Reserved. Ramps and staircas...
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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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Computer.
which can activate computer commands in conjunction with voice recognition software. “Tablet” computers are being developed that will allow users to interact with theirscreens using a penlike device. E The Central Processing Unit Information from an input device or from the computer’s memory is communicated via the bus to the central processing unit (CPU), which is the part of the computerthat translates commands and runs programs. The CPU is a microprocessor chip—that is, a single piece of sil...
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Nanotechnology.
ever-finer method of reducing material to the nanoscale size. Instead, nanostructures would be assembled atom by atom and molecule by molecule, from the atomiclevel up, just as occurs in nature. However, assembly at this scale has its own challenges. In school, children learn about some of these challenges when they study the random Brownian motion seen in particles suspended in liquids such as water. Theparticles themselves are not moving. Rather, the water molecules that surround the particles...
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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...
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Birth Control.
without a prescription and used alone or with a condom, diaphragm, or cervical cap. Spermicides used alone must be inserted deep into the vagina before each act ofintercourse and a woman should not douche for six to eight hours after intercourse. With typical use, spermicides used alone are effective in preventing pregnancyabout 74 percent of the time. They may cause an allergic reaction such as irritation of the vagina or penis. B Intrauterine Device The intrauterine device (IUD) is a small pl...
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Thomas Edison.
While Edison was working on the electric light, he made a scientific discovery that would become important to future generations. Edison noticed that particles of carbonfrom the filament blackened the insides of his light bulbs. This effect was caused by the emission of electrons from the filament, although Edison made the discoverybefore he and other scientists knew the electron existed. Not until 1897 did British physicist J. J. Thomson prove that the blackening observed by Edison was caused b...
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Thomas Edison - USA History.
While Edison was working on the electric light, he made a scientific discovery that would become important to future generations. Edison noticed that particles of carbonfrom the filament blackened the insides of his light bulbs. This effect was caused by the emission of electrons from the filament, although Edison made the discoverybefore he and other scientists knew the electron existed. Not until 1897 did British physicist J. J. Thomson prove that the blackening observed by Edison was caused b...
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Wireless Communications.
were large, heavy units. After the invention of the transistor in 1948, radios shrank in size to small handheld radio transceivers. Public two-way radios with severalfrequency options are widely available as well. Usually limited in range to a few miles, these units are great aids for such mobile professionals as construction workers,film crews, event planners, and security personnel. Simpler two-way radios, called walkie-talkies, have been popular children’s toys for years. Most walkie-talkiesb...
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Electronics.
electronic circuits. The resistors are made from carbon mixtures, metal films, or resistance wire and have two connecting wires attached. Variable resistors, with anadjustable sliding contact arm, are often used to control volume on radios and television sets. E Capacitors Capacitors consist of two metal plates that are separated by an insulating material ( see Capacitor). If a battery is connected to both plates, an electric charge will flow for a short time and accumulate on each plate. If th...
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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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Observatory - astronomy.
Ultraviolet radiation, X rays, and gamma rays have shorter wavelengths than visible light has. These types of radiation tell astronomers about the hottest and mostviolent phenomena in the universe. Earth’s atmosphere blocks most of this radiation, so astronomers must send their observatories above the atmosphere aboardballoons, rockets, or satellites. Ultraviolet telescopes are much like visible light telescopes, but X-ray telescopes must have special nested cylindrical mirrors to prevent Xrays...
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Automation.
Not all industries require the same degree of automation. Agriculture, sales, and some service industries are difficult to automate. The agriculture industry may becomemore mechanized, especially in the processing and packaging of foods; however, in many service industries such as supermarkets, for example, a checkout countermay be automated and the shelves or supply bins must still be stocked by hand. Similarly, doctors may consult a computer to assist in diagnosis, but they must makethe final...
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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...
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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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Network (computer science).
computer. Since there is only one token in the network, only one computer can transmit information at a time. Token Ring networks are now quite rare. Most LANs nowuse Ethernet technology. International Business Machines Corporation (IBM), the company that invented Token Ring in the early 1980s, no longer promotes thetechnology. In the mid-1990s a new protocol called Asynchronous Transfer Mode (ATM) was introduced. This protocol encodes data in fixed-sized packets called cells rather thanvariable...
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Telecommunications.
commonly referred to as wireless communications, use technologies such as cordless telephones, cellular radio telephones, pagers, and satellites. Wirelesscommunications offer increased mobility and flexibility. In the future some experts believe that wireless devices will also offer high-speed Internet access. C Wires and Cables Wires and cables were the original medium for telecommunications and are still the primary means for telephone connections. Wireline transmission evolved fromtelegraph...
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Computer Science.
theoretical research is called algorithmic complexity. Computer scientists in this field seek to develop techniques for determining the inherent efficiency of algorithmswith respect to one another. Another area of theoretical research called computability theory seeks to identify the inherent limits of computation. Software engineers use programming languages to communicate algorithms to a computer. Natural languages such as English are ambiguous—meaning that theirgrammatical structure and vocab...
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Galileo
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INTRODUCTION
Galileo (1564-1642), Italian physicist and astronomer who, with German astronomer Johannes Kepler, initiated the scientific revolution that flowered in the work of
English physicist Sir Isaac Newton.
V WORK IN ASTRONOMY During most of his time in Padua, Galileo showed little interest in astronomy, although in 1595 he declared in a letter that he preferred the Copernican theory that Earthrevolves around the Sun to the assumptions of Aristotle and Ptolemy that planets circle a fixed Earth ( see Astronomy: The Copernican Theory ; Ptolemaic System). A Observations with the Telescope In 1609 Galileo heard that a telescope had been invented in Holland. In August of that year he constructed a t...
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Galileo.
V WORK IN ASTRONOMY During most of his time in Padua, Galileo showed little interest in astronomy, although in 1595 he declared in a letter that he preferred the Copernican theory that Earthrevolves around the Sun to the assumptions of Aristotle and Ptolemy that planets circle a fixed Earth ( see Astronomy: The Copernican Theory ; Ptolemaic System). A Observations with the Telescope In 1609 Galileo heard that a telescope had been invented in Holland. In August of that year he constructed a t...
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Diving (underwater).
compensator (or control) device (BCD or BC), which the diver wears as a vest. By adding air to the BCD, the diver becomes more buoyant and rises. By releasing air,the diver becomes less buoyant and sinks. With minor adjustments of air, the diver can achieve neutral buoyancy. A third hose attaches to pressure gauges that diversuse to monitor how much air remains in the tank. A fourth hose attaches to a backup breathing device called an alternate air source, or octopus. Divers also wear a belt w...
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Electricity
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INTRODUCTION
Electricity, one of the basic forms of energy.
electrons in the neutral object are attracted to the positive object. Some of these electrons flow to the side of the neutral object that is nearest to the positive object.This side of the neutral object accumulates electrons and becomes negatively charged. Because electrons leave the far side of the neutral object while its protonsremain stationary, that side becomes positively charged. Since the negatively charged side of the neutral object is closest to the positive object, the attraction bet...
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Electronic Games.
arcade game of all time. With Pizza Time Theaters legitimizing the idea of arcades and hits such as Ms. Pac-Man , Asteroids , Donkey Kong , Tempest , Frogger , and Defender bringing new excitement to gaming, the coin-operated video game business boomed. In 1981 Americans spent 75,000 person-years and $5 billion playing video games at anestimated 4,300 arcades in the United States. Many popular arcade games also were translated for use on the Atari 2600 and its chief rivals in the homemarket—M...
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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...
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Body Scanner Research
Christmas 2009 when the Nigerian Abdul Mudallad avoided security men vigilance and failed to blow up a bomb during the flight from Amsterdam (Holland) to Detroit (US). In the wake the attempt, many governments over the w orld have decided to introduce a new technology device in the airports in order to strengthen the available measures. This technology device, called Body Scanners, like its name depicts - is a device built to facilitate a strict and reliable search of hazar dous materials t...
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Helicopter.
naturally flaps down so as to increase lift. Flapping allows the differences in lift caused by uneven rotor tip speed to cancel out, producing a stable ride. Many helicoptersuse mechanical hinges with lubricated bearings, but some use flexible straps made of a composite material in order to reduce the required maintenance. Helicopters require different amounts of lift and thrust at different times during flight, because the aerodynamic forces acting on them change during hovering andacceleration...
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Poliomyelitis.
Physical therapy helps patients with paralytic polio stretch and move affected muscles. This movement minimizes the atrophy, or shrinkage, of affected muscles andlimbs and builds strength. Exercises can also retrain working muscles to compensate for other muscles that have permanently lost the ability to move. Rehabilitativetherapy trains patients to use braces, crutches, and other devices that provide support and aid mobility. V PREVENTION OF POLIO Immunization with polio vaccine is the best w...
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Air Pollution.
Several pollutants attack the ozone layer. Chief among them is the class of chemicals known as chlorofluorocarbons (CFCs), formerly used as refrigerants (notably in airconditioners), as agents in several manufacturing processes, and as propellants in spray cans. CFC molecules are virtually indestructible until they reach thestratosphere. Here, intense ultraviolet radiation breaks the CFC molecules apart, releasing the chlorine atoms they contain. These chlorine atoms begin reacting withozone, br...
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Nuclear Weapons.
Regardless of the method used to attain a supercritical assembly, the chain reaction proceeds for about a millionth of a second, liberating vast amounts of heat energy.The extremely fast release of a very large amount of energy in a relatively small volume causes the temperature to rise to tens of millions of degrees. The resultingrapid expansion and vaporization of the bomb material causes a powerful explosion. VI PRODUCTION OF FISSILE MATERIAL Much experimentation was necessary to make the p...
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Temperature
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INTRODUCTION
Thermometers
Mercury and digital thermometers are the most common types of household devices for measuring body temperature.
range of the water, which differs for various species. Thus, for example, the increase in temperature of river water by only a few degrees as a result of heat dischargedfrom power plants may kill most of the native fish. See Water Pollution. The properties of all materials are also markedly affected by temperature changes. At arctic temperatures, for example, steel becomes very brittle and breaks easily,and liquids either solidify or become very viscous, offering high frictional resistance to...
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Installer un µcontroller F210A
Zavio F210A Quick Installation Guide Please follow the installation steps below to set up your F210A IP Camera. Check the package contents against the list below. See P.1 Physical overview. See P.1 Install the hardware and connect all cables. See P.2 Microsoft OS: Use the software CD to install Intelligent IP Installer. See P.2 Access the IP Camera using Intelligent IP Installer. See P.2 Mac OS using Safari Browser. See P.4 Change light environment setting. See P.5 Change the Web I...
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Chemical Analysis - chemistry.
inorganic reactions than by organic functional group chemistry. VII SPECTROSCOPIC TECHNIQUES Spectroscopy, or the study of the interactions of electromagnetic radiation with matter, is the largest and most nearly accurate class of instrumental methods used inchemical analysis and indeed in all of chemistry ( see Spectroscopy; Spectrum). The electromagnetic radiation (emr) spectrum is divided into the following wavelength regions: X ray, ultraviolet, visible, infrared, microwave, and radiowave....
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Federal Republic of Germany - country.
B Rivers and Lakes Rivers have played a major role in Germany’s economic development. The Rhine River flows in a northwesterly direction from Switzerland through much of westernGermany and The Netherlands into the North Sea. It is a major European waterway and a pillar of commerce and trade. Its primary German tributaries include theMain, Mosel, Neckar, and Ruhr rivers. The Oder (Odra) River, along the border between Poland and Germany, runs northward and empties into the Baltic; it provides an...
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Laser.
their atoms into laser light. Consequently, they are the most powerful continuous wave (CW) lasers—that is, lasers that emit light continuously rather than in pulses. C Liquid Lasers The most common liquid laser media are inorganic dyes contained in glass vessels. They are pumped by intense flash lamps in a pulse mode or by a separate gas laserin the continuous wave mode. Some dye lasers are tunable, meaning that the color of the laser light they emit can be adjusted with the help of a prism lo...
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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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Atom
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INTRODUCTION
Water Molecule
A water molecule consists of an oxygen atom and two hydrogen atoms, which are attached at an angle of 105°.
spontaneously break apart and change, or decay, into other atoms. Unlike electrons, which are fundamental particles, protons and neutrons are made up of other, smaller particles called quarks. Physicists know of six different quarks.Neutrons and protons are made up of up quarks and down quarks —two of the six different kinds of quarks. The fanciful names of quarks have nothing to do with their properties; the names are simply labels to distinguish one quark from another. Quarks are unique amo...
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Atom - chemistry.
Atoms have several properties that help distinguish one type of atom from another and determine how atoms change under certain conditions. A Atomic Number Each element has a unique number of protons in its atoms. This number is called the atomic number (abbreviated Z). Because atoms are normally electrically neutral,the atomic number also specifies how many electrons an atom will have. The number of electrons, in turn, determines many of the chemical and physical properties ofthe atom. The ligh...
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Le Wi-Fi
~ 1 ~ Wi -f i i s a pr etty r e cen t w i r el es s r a di o co mm uni cati o n te c hno l o gy us e d i n par ti cul ar i n co mp uti n g a cti v i ti es . I t i s us ed i n p ar ti c ul ar f o r w i r el es s l o cal n etw o r ks , a nd no w ad ay s i t’s t he f i r s t w ay to ac ces s t he i nter net. What are the advantages and the drawbacks of Wi -Fi technology, and how safe is it ? SUMMARY I - General Presentation .............
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Alternative Medicine.
The field of chiropractic was founded by David Daniel Palmer in the 1890s. He believed that joint subluxation, or a partial dislocation, is a causal factor in disease andthat removal of the subluxation by thrusting on the bony projections of the vertebrae restores health. In addition to manipulating and adjusting bone and tissue, particularly in the spinal column, chiropractors use a variety of manual, mechanical, and electrical treatments.Chiropractors are most widely recognized for providing d...
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Surrealism
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INTRODUCTION
Surrealism, artistic and literary movement that explored and celebrated the realm of dreams and the unconscious mind through the creation of visual art, poetry, and
motion pictures.
Hieronymus Bosch’s The Garden of Earthly Delights (about 1505-1510).© 2008 Salvador Dali, Gala-Salvador Dali Foundation / Artists Rights Society (ARS), New York./Bridgeman Art Library, London/New York Dreams, according to Freud, were the royal road to studying the unconscious, because it is in dreams that our unconscious, primal desires manifest themselves. Theincongruities in dreams, Freud believed, result from a struggle for dominance of ego and id. In attempting to access the real workings of...
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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...
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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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Criminal Punishment.
In the United States and Canada, younger offenders may be sentenced to highly regimented, military-style correctional programs known as boot camps. Generally,offenders volunteer to participate in boot camp programs to avoid other types of incarceration. At boot camps, officials subject offenders to strict discipline and physicaltraining. They also provide educational or vocational programs. Boot camps serve as an alternative to traditional, long-term incarceration and attempt to train offenderst...
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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...
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English Literature
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INTRODUCTION
English Literature, literature produced in England, from the introduction of Old English by the Anglo-Saxons in the 5th century to the present.
evident. That feature is typical of other Old English literature, for almost all of what survives was preserved by monastic copyists. Most of it was actually composed byreligious writers after the early conversion of the people from their faith in the older Germanic divinities. Sacred legend and story were reduced to verse in poems resembling Beowulf in form. At first such verse was rendered in the somewhat simple, stark style of the poems of Caedmon, a humble man of the late 7th century who w...
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Infrared Astronomy - astronomy.
ft above sea level. With the launch of the Infrared Astronomical Satellite (IRAS), by the United States, the United Kingdom, and The Netherlands in 1983, infraredastronomy took another leap forward. This mission surveyed the entire sky at wavelengths of 12, 25, 60, and 100 microns (1 micron is a millionth of a meter) until itsonboard supply of liquid helium ran out. A short time later infrared astronomy was revolutionized by the first introduction of devices that could take infrared images. Thea...
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Gun Control.
Bridgeport, Connecticut, alleged that gun manufacturers acted negligently (not carefully enough) when marketing and distributing their products. The cities contended that gun manufacturers oversupplied gun dealers in areas with weak gun restrictions, knowing that individuals from areas with tougher laws wouldpurchase the guns. Other cities, such as New Orleans, Louisiana, and Atlanta, Georgia, used a different approach in lawsuits against gun makers. These cities allegedthat gun makers failed to...
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Comedy
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INTRODUCTION
Laurel and Hardy
Stan Laurel, in overalls, and Oliver Hardy, left, formed one of the most popular comedy teams in motion-picture history.
The elements and techniques of comedy are diverse and differ from culture to culture. More than tragedy or serious drama, comic entertainment is controlled by socialconventions that define the boundaries of acceptable humor and topics that are taboo or off-limits for humor. What is considered funny in one place and time may beforbidden culturally or viewed as infantile or in poor taste in another. Virtually every component of human behavior is subject to comic treatment. This includes bodilyfunc...
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Cubism
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INTRODUCTION
Cubism, movement in modern art, especially in painting, invented by Spanish artist Pablo Picasso and French artist Georges Braque in 1907 and 1908.
Mont Sainte-Victoire by CézanneFrench artist Paul Cézanne painted Mont Sainte-Victoire, a mountain near his home in Provence in southern France, onmany occasions. Over time, the images he produced became flatter, less realistic, and more abstract. In this late version,painted from 1902 to 1904, patches of color barely indicate the mountain, sky, and foreground, while creating a rhythmicpattern across the painting’s surface. The mountain and sky, both intensely blue, appear almost to merge.Philad...