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Directions: Read the following passages and then answer IN COMPLETE SENTENCES the questions which follow each passage. Scientists are preparing to boot up the world’s most powerful supercomputer, a machine with the power of 500,000 PCs and a thirst for electricity that will leave its owners with an annual bill of ￡25m. The computer, called Titan, will use graphics processors similar to those in PlayStation gaming consoles to tackle some of the toughest tasks in science. Until now most supercomputers have used normal processors souped-up versions of those in laptops and PCs. Decoding new flu strains—one of the most demanding jobs in computing—is one task that engineers at Oak Ridge National Laboratory in Tennessee might set Titan. The supercomputer could also design vaccines to stop the flu bugs before they can spread. Sumit Gupta, a senior engineer at Nvidia, the company that is making the Titan processors, said: "Computer simulations can explore lm different drug [vaccine] candidates within weeks or months." Titan will carry out 20,000 trillion calculations a second, about 4,000 trillion calculations a second faster than Sequoia, the world’s current fastest computer, which is used to simulate nuclear explosions. A typical PC carries out 40 billion calculations a second. "Oak Ridge is in the race to have the fastest supercomputer in the world," the laboratory said in a statement. Supercomputing has been one of the fastest and most revolutionary of technological trends. As with ordinary computers, its history goes back to the 1930s and 1940s when the first digital computers were built, with the first transistor-based machine being produced in 1956. The development of supercomputers owes much to the work of Seymour Cray, an electrical engineer who realized the potential of linking processors together to create much faster machines. Experts differ on which of his machines should be called the first supercomputer but Cray-1, built in 1976, is commonly cited. Back then its ability to perform 160m calculations a second was seen as revolutionary. Nowadays that machine would have a fraction of the computing power of a smartphone. "Computers like these have revolutionized science," said Paul Calleja, director of the high-performance computing centre at Cambridge University. "In the past, researchers devised theories and then they carried out experiments. What supercomputers do is offer us a third way—computer modelling. We can devise a theory about, say, the way atoms and molecules or materials might behave, and then build a computer model to see if it works." Such approaches are now standard throughout science and engineering. In the aviation industry, for example, where engineers once tested the effects of bird strikes on aircraft by throwing or firing a dead chicken into a jet turbine, they now have vast databases on the composition of chickens and their behaviour when they hit spinning turbines. Similarly, car designers use computer models to test how vehicles will crumple in a crash and what injuries the occupants might sustain. In the past, such tests could be conducted only by using real cars occupied by dummies or even dead bodies. Computer modelling has sharply cut the need for such testing. Titan will be made available to scientists in various fields. One programme will tackle climate change and how rising greenhouse gas emissions might affect different parts of the world. Another will study the way fuel burns in diesel engines spinning thousands of times a minute, to find ways of boosting efficiency. "These types of calculations require massive computing power," said Calleja, whose own supercomputer at Cambridge has been used to design America’s Cup sailing boats. "The pressure to build even more powerful machines is huge." Supercomputers are no longer the preserve of the military or academic establishments, however. Many high-street companies, from supermarkets to banks and insurance firms, own them. Tesco, for example, is investing in a ￡65m supercomputing system in Watford, Hertfordshire, to underpin its online retail and banking businesses. Such computing power, combined with data extracted from loyalty cards and other sources, means supermarkets can build models of consumer behaviour to predict what they will want to buy even before their customers know it. Walmart, the American owner of Asda, has been using a supercomputer for several years and has even combined it with weather forecasts to work out what products will be needed in stores when storms or other events arise. Researchers at Cambridge are now working on perhaps the most ambitious computing project of all—to build a machine 150 times faster than Titan to help search for planets capable of supporting life. The computer, capable of between 2m trillion and 3m trillion calculations a second, will be hooked up to the Square Kilometre Array, a giant radio telescope made up of thousands of radio dishes that is under construction across South Africa and Australia. Calleja said the supercomputer’s key task would be to collate and analyse all the data captured by each dish. "It is the most ambitious project we have ever attempted," he said. What is Titan What advantages does Titan have
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Go to the mall these days and it’s hard not to feel as if you’re being messed with, which is why J. C. Penney’s recent not-going-to- take-it-anymore ad rings true. You may have seen it. consumer upon consumer screaming "No!" as coupons flood out of a mailbox, crowds mass before dawn for a Black Friday-esque sale and store windows are stocked with items that are now 62% off. Too bad you bought them at full price, sucker. The ad is staged and exaggerated, but the frustrations are real. To be a shopper—and not walk away screaming—is to come to grips with the reality that unless you are using shopbots and taking on bargain hunting as a full-time job, as some have, you are almost never going to get the lowest price. So when Penney’s newly appointed CEO, Ron Johnson, declared in mid-January that most of the original prices in his store have long been "fake" and inflated, the only surprising thing was that he had the guts to admit it. More surprising. Johnson said he was going to make changes. Instead of facing infinite discounts and promotions—there were 590 different "sales" at Penney alone in 2011—the department store’s shoppers will now see just three price categories. One will represent discounted seasonal items that change monthly. Another is clearance merchandise marked down on the first and third Fridays of each month. But the majority of goods will be offered every day at 40% or 50% less than the prices Penney used to charge. In retail parlance that’s called EDLP, as in "everyday low price". It’s a radical shift for a promotional department store like Penney. The "fair and square" makeover also includes a new logo, store upgrades and in-store boutiques that will feature fewer brands. The big discount chains Walmart and Target have long staked out EDLP, but mostly we live in a promotional, markdown world. And all those Sunday circulars, flash deals and holiday sales events—which seemed more intense than ever last year—have turned shopping into retail combat. According to the management-consulting firm A.T. Kearney, more than 40% of the items we bought last year were on sale. That’s up from 10% in 1990. Penney has been a notorious discounter, with nearly three-quarters of revenue coming from goods sold at 50% or more off list price—whatever that is—and less than 1% from fullprice merchandise. If anyone is equipped to transform Penney, it’s the new CEO. Johnson joined the retailer in November, arriving from Apple, where for the past decade he presided over the computer company’s huge retail success. Apple loves price maintenance and loathes heavy discounting and sales gimmicks. Johnson believes Penney’s customers will appreciate pricing clarity, not to mention sleeping in. "I don’t think customers like having to come to a store between 8 and 10 a.m. on a Sunday in order to get the best price on swimwear," he said. But iPads are not underwear or makeup. "My intuition is that, in the long run, the changes won’t be effective," says Kit Yarrow, consumer psychologist and author of Gen BuY: How Tweens, Teens and Twenty-Somethings Are Revolutionizing Retail. "A discount gives shoppers the incentive to buy today. Without that, there’s no sense of urgency for people to purchase things that, frankly, they probably don’t need." Today’s consumers respond well to transparency, though, and to businesses that admit their mistakes. The success of the Domino’s "We Were Wrong" campaign is Exhibit A. So Penney’s disavowal of marketing games should build customer trust. At least initially, the slashing of all list prices should also boost sales. But what happens when the novelty wears off and nothing seems special about everyday prices By then, Johnson hopes, J. C. Penney will be a place that shoppers love because they like the merchandise and atmosphere, and they won’t fret about doing better elsewhere. Why does the author think Johnson is the most suitable person for the task of transforming Penney
Despots and tyrants may have changed the course of human evolution by using their power to force hundreds of women to bear their children, says new research. It shows that the switch from hunter-gathering to farming about 8,000 - 9,000 years ago was closely followed by the emergence of emperors and elites who took control of all wealth, including access to young women. Such men set up systems to impregnate hundreds, or even thousands, of women while making sure other men were too poor or oppressed to have families. It means such men may now have hundreds of millions of descendants, a high proportion of whom may carry the genetic traits that drove their ancestors to seek power and oppress their fellow humans. "In evolutionary terms this period of human existence created an enormous selective pressure, with the guys at the top who had the least desirable traits passing on their genes to huge numbers of offspring," said Laura Betzig, an evolutionary anthropologist. She has studied the emergence of the world’s first six great civilisations in Mesopotamia, Egypt, India, China, Mexico and Peru. In each she found that emperors created systems to "harvest" hundreds of the prettiest young women and then systematically impregnate them. Betzig has studied the records left by the six civilisations to work out how many children were born to emperors. "In China they had it down to a science. Yangdi, the 6th-century Sui dynasty emperor, was credited by an official historian with 100,000 women in his palace at Yangzhou alone," she said. "They even had sex handbooks describing how to work out when a woman was fertile. Then they would be taken to the emperor to be impregnated. It was all organised by the state so the emperor could impregnate as many women as possible. And they had rules, like all the women had to be under 30 and all had to be attractive and symmetrical. This was the system in China for more than 2,000 years." Others relied on violence. One genetic study showed that Genghis Khan, the 13th-century Mongol warlord, who was renowned for sleeping with the most beautiful women in every territory he conquered, now has about 16m male descendants. This compares with the 800 people descended from the average man of that era. Betzig also studied primitive societies. She found that the small bands of hunter-gatherers were the most egalitarian, with men and women able to have the number of children they wanted. "This freedom is probably because they were so mobile. If their group got taken over by a big guy who tried to control resources, the others could simply leave and find somewhere else," she said. This system broke down when the world’s first civilisations emerged about 8,000 years ago based on farming. All began on fertile river plains surrounded by mountains or deserts that made it difficult to leave. Such situations were perfect for the emergence of elites and emperors. In a paper published recently, Betzig has catalogued the same trend in each of the great early civilisations. Such systems arose in Britain as well, especially in the feudal era. "Lords then had sexual access to hundreds of dependent serfs ... with up to a fifth of the population ’in service’," Betzig said. She is to publish a book, The Badge of Lost Innocence, exploring why that era has ended. "The European discovery of the Americas changed everything," she said. "Along with the emergence of democracy it offered millions of people the chance to emigrate or get rid of despotic regimes. The literature of that time shows people wanted to have families of their own and for the first time in thousands of years they had that chance. " Betzig has studied the records left by the following civilisations EXCEPT ______ to work out how many children were born to emperors.
J.K. Rowling’s first novel for adults, which treads on very different ground to her bestselling Harry Potter series, is set to become a publishing sensation when it hits bookshelves next week. Waterstones, the country’s biggest book-chain store, revealed that the comic novel, The Casual Vacancy, has received the largest number of pre-order sales this year. This number is believed to be five figured, although online pre-orders have reportedly reached well over a million already. The RRP for the paperback is ￡20 but many outlets are reducing this considerably with Waterstones pricing it at ￡10. The secrecy, as well as the excitement, around Rowling’s latest offering, has guaranteed its status as the biggest publishing event of the year. Waterstones is opening its doors an hour earlier than usual, at 8 a.m., on its official publication date next Thursday. Until then, Rowling’s publisher Little, Brown has stipulated that the books should not even appear on display. Staff will come in early to put out display copies and prepare for the crowds. Jon Howells, a spokesman for Waterstones, described it as one of the first "Super Thursdays" leading up to Christmas, not least because Jamie Oliver was also publishing his book, 15-Minute Meals, on the same day. Mr. Howells said that while he anticipated a big rush at the outset, the book would, in all likelihood, not inspire the equivalent of Pottermania. "Certainly, the anticipation for J.K. Rowling’s book has been great because it’s the first non-Harry Potter book and it is for a purely adult audience. I think it will see a fantastic level of first day and first weekend sales and after that people will come to it more steadily." "We are treating it as a very different thing from the Harry Potter books. The way readers will approach this will be different. A lot of the readers will be curious and interested in what this book can do for them. There was a huge sense of urgency with the Harry Potter books, and people wanted to read them quickly so that they would not find out the plot through other mediums, while this is a standalone story," he said. A spokeswoman for Tesco, which will also be stocking the book, said: "If the hits on the Tesco Books blog are anything to go by, we think it could be one of our bestselling books in the run-up to Christmas." The plot of the book, which revolves around the inhabitants of a small English town, has been fiercely guarded, and newspaper reviewers have been asked to sign the kind of long and stiffly worded pre-publication confidentiality contracts that a celebrity footballer might use to protect his darkest secrets. A limited number of copies will be delivered by hand to reviewers’ homes today. Rowling is due to attend her only question-and-answer session in front of a live audience in London on the day of publication. The event, at the 900-seat Queen Elizabeth Hall in the Southbank Centre, sold out within 48 hours and will also be attended by the world’s media. The Southbank Centre condemned the selling of single ￡12 tickets on eBay for ￡85 each. The event, which will last just under two hours including a 30-minute Q & A with the audience, will be transmitted in a live feed on YouTube. Rowling will sign books afterwards, and audience members are limited to one copy per person. Next month she will appear at the Cheltenham Literary Festival and sign copies there. Little, Brown refused to reveal the numbers of copies that have been printed so far—but the book is expected to sell millions. The word "Pottermania" in the sentence "... the book would, in all likelihood, not inspire the equivalent of Pottermania" (para. 3) can best be paraphrased as ______.
When I recently mentioned to a pregnant acquaintance that I was writing a book about egg freezing (and had frozen my own eggs in hopes of preserving my ability to have children well into my 40s), she replied, "You’re so lucky. I wish I had known to freeze my eggs. " She was 40 years old and wanted two children, so she and her husband were planning to start trying to conceive a second child shortly after the birth of their first. "Now everything is a rush," she said. Married at 38, she didn’t think to talk to her obstetrician-gynecologist about fertility before then. If her doctor had brought up the subject, she said, she might have put away some eggs when she was younger. In our fertility-obsessed society, women can’t escape the message that it’s harder to get pregnant after 35. And yet, it’s not a conversation patients are having with the doctors they talk to about their most intimate issues—their OB-GYNs—unless they bring up the topic first. OB-GYNs routinely ask patients during their annual exams about their sexual histories and need for contraception, but often missing from the list is, "Do you plan to have a family" OB-GYNs are divided on whether it’s their responsibility to broach the topic with patients. Those who take an "ask me first" approach understandably don’t want to offend women who don’t want children, or frighten those who do. It doesn’t take much for an informational briefing to spiral into a teary heart-to-heart about dating woes. Do you reassure a distraught 38-year-old that she’s still got time; encourage her to seriously consider having a baby on her own; or freak her out so she settles for a lackluster relationship And considering that fertility figures are averages (while one woman may need fertility treatment at age 36, another can get pregnant naturally at 42), when is the right age to sound the alarm But the biggest impediment to bringing the issue up was that doctors didn’t have many good recommendations for a single woman. she could either use an anonymous donor’s sperm to have a baby today, or she could fertilize her eggs with it and freeze the resulting embryos for future use. Now, a better option is gaining credibility. Egg freezing (a technique that allows women to store their unfertilized eggs to use with a future partner when they are older) has been available in the United States since the early 2000s, but success rates at first were low and doctors have been hesitant to push it. The American Society for Reproductive Medicine said the technique shouldn’t be "offered or marketed as a means to defer reproductive aging", and deemed it "experimental". Last week, the doctors’ society announced that it was removing the experimental label (though it stopped short of endorsing widespread use of egg freezing to put off having children). After reviewing four randomized controlled trials, it found little difference in the effectiveness of using fresh or frozen eggs in in-vitro fertilization, and said that babies conceived from frozen eggs faced no increased risk of birth defects or developmental problems. The procedure isn’t a panacea. It’s terribly expensive—often $15,000—and is not usually covered by insurance. In addition, there’s a worrisome lack of data regarding the success rates of eggs frozen by the women at the end of their baby-making days. The majority of the women in the four studies were under 35, and it warned against giving women who want to delay childbearing "false hope" that their frozen eggs will work when they are ready to get pregnant years later. Although estimates of the number of American women who have frozen their eggs for nonmedical reasons are in the thousands, very few have yet returned to thaw them—there are only a couple of thousand babies born from frozen eggs in the world. Women should be allowed to come to their own conclusions and take their own risks—there’s a fine line between doctors’ "mentioning" and "suggesting" the procedure—but this is an option they should be hearing about from their OB-GYNs. To standardize the message, professional groups like the American Congress of Obstetricians and Gynecologists should create pamphlets that doctors can give to patients. OB-GYN residents also can learn suggested scripts that present the information in a nonbiased, non alarmist way. I first learned about egg freezing from a friend who had talked to her OB-GYN about whether she should freeze, given her family’s history of premature menopause. When I asked my doctor about the procedure, she said she had heard that the success rates had recently improved and gave me the name of a respected fertility doctor. As a result, I stashed away several batches of eggs between the ages of 36 and 38—just before the cutoff at which many doctors no longer consider eggs worthwhile to save. I was fortunate, because I knew to ask. We must go one step further and expect OB-GYNs to bring up family planning at every annual visit, so that women have the information they need to choose to take charge of their fertility. Perhaps more women will think about freezing in their early to mid-30s, when their chances of success are greater. Or maybe, after being asked about their plans from their very first visit, more will decide to start families when their eggs are at their prime, and won’t even need to freeze. Which of the following CANNOT be true about fertility according to the passage
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