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Once found almost entirely in the western United States and in As. ia, dinosaur fossils are now being discovered on all seven continents. A host of new revelations emerged in 1998 that promise to reshape scientists’ views of dinosaurs, including what they looked like and when and where they lived.It is doubtful that Tyrannosaurus Rex had lips or that Triceratops had cheeks, says Lawrence Witmer, an assistant professor of anatomy at Ohio University in Athens, Ohio. Witmer was a leading researcher for a study on dinosaur anatomy that was presented at the annual meeting of the Society for Vertebrate Paleontology, which concluded on October 3 in Snowbird, Utah.Witmer’s study reached its conclusions by using high-tech computerized axial tomography (CT or CAT) scans along with comparative anatomy studies. For example, the theory that Triceratops and similar dinosaur species had cheeks was based on past comparisons with mammals such as sheep. But Witmer’s careful analysis found the structure of the triceratops jaw and skull made it more likely that Triceratops had a beak like that of an eagle. Witmer said that scientists should use birds and crocodiles as models when researching the appearance of dinosaurs.In early October scientists announced that they had confirmed the discovery of a new type of ceratopsian dinosaur. The dinosaur’s bones, found in New Mexico in 1996, are forcing paleontologists to rethink their theories about when eeratopsians migrated to what is now North America.Scientists previously thought that ceratopsians, the group that included the well known Triceratops, arrived in North America from Asia between 70 million and 80 million years ago. During this time, the late Cretaceous Period, the earth’s two supercontinents—Laurasia in the north and Gondwanaland in the south—were in the process of pulling apart, cutting dinosaur populations off from each other and interrupting migratory patterns.The fossilized bones, found by eight-year-old Christopher Wolfe and his father, paleontologist Doug Wolfe of the Mesa Southwest Museum in Arizona, date to about 90 million years ago. This could mean that ceratopsians originated in North America and migrated to Asia rather than the reverse, paleontologists said. Doug Wolfe named’ the important new species of dinosaur Zuniceratops Christopheri after his son.An expedition from the Universities of Alaska in Anchorage and Fairbanks has discovered a region in remote northern Alaska so rich in fossilized dinosaur tracks that team members dubbed it the "dino expressway". The trampled area was found during the summer of 1998 on Alaska’s North Slope near the Brooks Range.The team found 13 new track sites and made casts from the prints of five different types of dinosaurs. The rock in which the prints were found dates to more than 100 million years ago, or about 25 million years older than the previously discovered signs of dinosaurs in the Arctic region. Paleontologists said that the new findings provide important evidence that dinosaurs migrated between Asia and North America during the early and mid-Cretaceous Period, before Asia split off into its own continent.Two rich fossil sites in the hills of Bolivia have been recently discovered, exciting paleontologists and dinosaur buffs. This discovery includes one of the most spectacular dinosaur trackways ever found.The discovery of a large site in the mountain region of Kila Kila in southern Bolivia was announced in early October. Here scientists found the tracks of at least two unknown species of dinosaur. These included a large quadruped (four-footed) dinosaur that was probably about 20m (about 70 ft) long.The other site, located not far from the Bolivian city of Sucre, was uncovered in a cement quarry by workers several years ago but was not brought to paleontologists’ attention until the middle of 1998. The site features a vertical wall covered with thousands of dinosaur prints representing more than 100 different species. The tracks date back to between 65 million and 70 million years ago. Since dinosaurs are believed to have died out around 65 million years ago, the prints were likely made by some of the last dinosaurs on earth.Scientists speculated that the tracks were made at the edge of a lake or swamp and were then hardened and preserved. The rock containing the tracks was then pushed into a vertical position over millions of years of geologic activity. Dinosaur eggs have also been found at the site, which paleontologists are working to preserve before it falls victim to erosion. Paleontologists hope to study the site and learn about the diet and physical characteristics of the dinosaurs that are represented there. Newly-found fossilized tracks in Alaska proved that dinosaurs’ migration between Asia and North America took place().
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As every ancient mariner knew, traveling by sail is a simple way to go. Though the winds could be fickle and the boats pokey, the energy source that moved the ship was free, plentiful and renewable. Now the same technology that conquered the oceans of Earth may conquer the ocean of space.This week a Russian and American consortium will announce plans for an April launch of the first so-called solar-sail vehicle, a multicasted spacecraft that will use sunlight to push itself along. To a public raised on smoke-and-tire rocketry, the idea of drawing energy straight from space seems fanciful. To the people behind the new ship, however, the technology is not only sensible but inevitable, the easiest way to reinvent the business of cosmic travel. "This allows us to use very little fuel to fly very great distances," says Bud Schurmeier, a former NASA engineer and an adviser to the project. "It’s an in triguing concept."The idea behind solar sailing is simple. Although light is made of massless particles called photons, such ephemeral things exert real pressure, especially when they flow so close a source as the sun. Attach a sail of lightweight Mylar or other material to a spacecraft, set it up in the path of that outrushing energy, and you ought to be able to move in almost any direction.NASA has a keen interest in solar sailing and had budgeted $ 5 million to investigate 17 possible missions. It may select one as early as next month. But while the space agency has been mulling plans, the people behind the new ship, dubbed Cosmos I, have been getting set to fly. The project is the brainchild of Russia’s Babakin Space Center, near Moscow, and the Planetary Society in Pasadena, Calif. , a think tank founded in 1979 by astronomer Carl Sagan and others. The two groups had long been developing plans for a solar-sail mission but got the cash to make it happen only last year when Ann Druyan, Sagan’s widow and head of the Media Company Cosmos Studios, and Joe Firmage, the founder of US Web, threw their names and about $ 4 million behind the effort. "I had talked to people about solar sailing before," says Lou Friedman ,former engineer at the Jet Propulsion Laboratory in Pasadena and director of the Planetary Society, "but between the Russians’ capabilities and Ann’s vision, I knew this one would click."The spacecraft is a 3-ft. metal with eight 35-ft. metallic wings. Mylar petals sprout from it -- though the prototype used in the April launch will have just two petals. Mounted atop a reconfigured Russian ICBM and launched from a sub in the B arents Sea, the Cosmos I will fly to an altitude of 260 miles, where it will deploy the wings and float for a minute of so. If all goes well, the wings will then be jettisoned and the sphere aerobraked back to Earth, its bounce-down on Russian soil cushioned by air bags.By some measures, this cosmic lob shot is not that impressive, but for solar-sail scientists, the engineering is every thing. Few doubt that when sunlight strikes the wings, the spacecraft will accelerate; the key is building wings that can open and pivot, allowing the ship to tack into the solar stream. If this mission works, a more ambitious orbital flight, using the eight-paneled craft, is set for the end of the year. The space-craft could circle Earth for months, surfing the sun until designers shut it down. "There will be a grandeur to it," says Druyan, "a 70-ft. sail that will be visible to the whole plan et."Grandeur aside, critics wonder if solar sails have a future. The technique is problematic in Earth orbit, since the changing position of sun relative to the space-craft makes constant tacking necessary. Sailing is best used for as the crow flies shots to neighboring planets. Even in these cases, progress can be slow, since sunlight exerts, at most, 2 lbs. of pres sure per square half-mile, requiring a year or more to rev a spacecraft to interplanetary speeds. Worse, beyond Jupiter, sunlight flickers out almost entirely; to go any farther would require energy beamen from Earth orbit, perhaps by giant laser howitzers. "None of these things has been tested, "says Mel Monte-merlo, one of NASA’s solar-sailing chiefs. "We have a long way to go."Whether that will continue to seem such a long way may depend on the spring-time flight of Cosmos I. A successful mission has a way of making impossible technologies seem possible -- a big burden for a small rocket that will, for one day at least, carry the hopes of the world’s space community. What does "brainchild" in the paragrapth 4 mean().
3.2□△6 If □ and △ each represent single digits in the decimal above, what digit does □ represent ？（） (1)When the decimal is rounded to the nearest tenth, 3.2 is the result. (2)When the decimal is rounded to the nearest hundredth, 3.24 is the result.
The story of Polly Klaas’ murder by a man with a history of violence galvanized California voters into passing the state’s three-strikes-and-you’re-out law in 1994. Two dozen states and the federal government have now adopted similar laws. Still, only in California can conviction on any third felony put someone behind bars for life. That singularity points to what is wrong with the California law, despite its emotionally wrenching origins.Eleven years after Polly was snatched from her upstairs bedroom and murdered, voters are troubled by other stories--about the Army veteran who stole $153 worth of videotapes or the father who pinched a box of diapers for his baby, both now in prison for life, and about the $31,000 that taxpayers pony up every year to house such individuals. Those tales should push voters to pass Proposition 66, correcting a gross injustice while reserving the harshest punishment for those who commit the worst crimes.Proposition 66 would limit third-strike offenses to serious or violent felonies; that’s the law many voters now say they thought they passed back in 1994. Excluded would be crimes like petty theft, passing a bad check or holding a small amount of drugs. These offenses would remain felonies for repeat offenders, who could still get longer prison terms for each new crime. Only the life sentence is excluded.Of California’s 7,300 third-strikers, 4,200 are doing 25 years to life for a nonserious or nonviolent felony. Proposition 66 also requires judges to resentence these third-strikers, meaning some who have already served several years behind bars may be freed.Los Angeles County Dist. Atty. Steve Cooley first campaigned for office in 2000 arguing that the 1994 law was unduly harsh and wisely promising not to charge as strikes most nonviolent, nonserious felonies without a good reason. Because Cooley has made good on that promise, his opposition to Proposition 66 is particularly disappointing. He--along with Gov. Arnold Schwarzenegger, Oakland Mayor and former Gov. Jerry Brown and Atty. Gen. Bill Loekyer--now insists, wrongly in our view, that the measure would flood the streets with predators. Those who might be released would have already done time for their crimes, just not life.Proposition 66 does not eliminate the three-strikes law. It restores voters’ original intent to keep violent criminals off the street for good. That said, like almost every initiative, Proposition 66 is not a model of nuanced legislation. It goes too far in narrowing the universe of "third strikes". If it passes, lawmakers in Sacramento should reinstate serious offenses like burglary and arson to that list.Then again, if Sacramento had fixed the three-strikes law in the first place, and not been so cowered by the fear of seeming "soft on crime", this proposition wouldn’t be needed now. The author of the passage thinks that ().
St. Paul didn’t like it. Moses warned his people against it. Hesiod declared it "mischievous" and "hard to get rid of it," but Oscar Wilde said, "Gossip is charming." "History is merely gossip," he wrote in one of his famous plays. But scandal is gossip made tedious by morality.In times past, under Jewish law, gossipmongers might be fined or flogged. The Puritans put them in stocks or ducking stools, but no punishment seemed to have the desired effect of preventing gossip, which has continued uninterrupted across the back fences of the centuries.Today, however, the much-maligned human foible is being looked at in a different light. Psychologists, sociologists, philosophers, even evolutionary biologists are concluding that gossip may not be so bad after all.Gossip is "an intrinsic valuable activity," philosophy professor Aaron Ben-Zee states in a book he has edited, entitled Good Gossip. For one thing, gossip helps us acquire information that we need to know that doesn’t come through ordinary channels, such as: "What was the real reason so-and-so was fired from the office" Gossip also is a form of social bonding, Dr. Ben-Zee says. It is "a kind of sharing" that also "satisfies the tribal need—namely, the need to belong to and be accepted by a unique group." What’s more, the professor notes, "Gossip is enjoyable."Another gossip groupie, Dr. Ronald De Sousa, a professor of philosophy at the University of Toronto, describes gossip basically as a form of indiscretion and a "saintly virtue", by which he means that the knowledge spread by gossip will usually end up being slightly beneficial. "It seems likely that a world in which all information were universally available would be preferable to a world where immense power resides in the control of secrets," he writes.Still, everybody knows that gossip can have its ill effects, especially on the poor wretch being gossiped about. And people should refrain from certain kinds of gossip that might be harmful, even though the ducking stool is long out of fashion.By the way, there is also an interesting strain of gossip called medical gossip, which in its best form, according to researchers Jerry M. Sols and Franklin Goodwin, can motivate people with symptoms of serious illness, but who are unaware of it, to seek medical help.So go ahead and gossip. But remember, if (as often is the case among gossipers) you should suddenly become one of the gossipers instead, it is best to employ the foolproof defense recommended by Plato, who may have learned the lesson from Socrates, who as you know was the victim of gossip spread that he was corrupting the youth of Athens: When men speak ill of thee, so live that nobody will believe them. Or, as Will Rogers said, "Live so that you wouldn’t be ashamed to sell the family parrot to the town gossip.\ Which of the following statements is true according to the text().
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