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Macy’s reported its sales plunged 5.2% in November and December at stores open more than a year, a disappointing holiday season performance that capped a difficult year for a department store chain facing wide-ranging challenges. Its flagship stores in major U.S. cities depend heavily on international tourist spending, which shrank at many retailers due to a strong dollar. Meanwhile, Macy’s has simply struggled to lure consumers who are more interested in spending on travel or dining out than on new clothes or accessories.The company blamed much of the poor performance in November and December on unseasonably warm weather. “About 80% of our company’s year-over-year declines in comparable sales can be attribut¬ed to shortfalls (短缺)in cold-weather goods,” said chief executive Terry Lundgren in a press release. This prompted the company to cut its forecasts for the full fourth quarter.However, it’s clear that Macy’s believes its troubles run deeper than a temporary aberration (偏离) off the thermometer. The retail giant said the poor financial performance this year has pushed it to be¬gin implementing $400 million in cost-cutting measures. The company pledged to cut 600 back-office po¬sitions, though some 150 workers in those roles would be reassigned to other jobs. It also plans to offer “voluntary separation” packages to 165 senior executives. It will slash staffing at its fleet of 770 stores, a move affecting some 3,000 employees.The retailer also announced the locations of 36 stores it will close in early 2016. The company had previously announced the planned closures, but had not said which locations would be affected. None of the chain's stores in the Washington metropolitan area are to be closed.Macy’s has been moving aggressively to try to remake itself for a new era of shopping. It has plans to open more locations of Macy’s Backstage, a newly-developed off-price concept which might help it better compete with ambitious T. J. Maxx. It’s also pushing ahead in 2016 with an expansion of Bluemercury, the beauty chain it bought last year. At a time when young beauty shoppers are often turning to Sephora or Ulta instead of department store beauty counters, Macy's hopes Bluemercury will help strengthen its position in the category.One relative bright spot for Macy’s during the holiday season was the online channel, where it rang up “double-digit” increases in sales and a 25% increase in the number of orders it filled. That relative strength would be consistent with what was seen in the wider retail industry during the early part of the holiday season. While Thanksgiving, Black Friday and Cyber Monday all saw record spending online, in¬store sales plunged over the holiday weekend.What does the author say about the shrinking spending of international tourists in the U.S.?What does Macy’s believe about its problems?In order to cut costs, Macy's decided to(  ).Why does Macy’s plan to expand Bluemercury in 2016?What can we learn about Macy's during the holiday season?

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Open data sharers are still in the minority in many fields. Although many researchers broadly agree that public access to raw data would accelerate science, most are reluctant to post the results of their own labors online.Some communities have agreed to share online一geneticists, for example, post DNA sequences at the GenBank repository (库),and astronomers are accustomed to accessing images of galaxies and stars from, say, the Sloan Digital Sky Survey, a telescope that has observed some 500 million objects—but these remain the exception, not the rule. Historically, scientists have objected to sharing for many rea¬sons: it is a lot of work; until recently, good databases did not exist; grant funders were not pushing for sharing; it has been difficult to agree on standards for formatting data; and there is no agreed way to assign credit for data.But the barriers are disappearing, in part because journals and funding agencies worldwide are en¬couraging scientists to make their data public. Last year, the Royal Society in London said in its report that scientists need to “shift away from a research culture where data is viewed as a private preserve”. Funding agencies note that data paid for with public money should be public information, and the scien¬tific community is recognizing that data can now be shared digitally in ways that were not possible be¬fore. To match the growing demand, services are springing up to make it easier to publish research products online and enable other researchers to discover and cite them.Although calls to share data often concentrate on the moral advantages of sharing, the practice is not purely altruistic (利他的).Researchers who share get plenty of personal benefits, including more connections with colleagues, improved visibility and increased citations. The most successful sharers— those whose data are downloaded and cited the most often—get noticed, and their work gets used. For example, one of the most popular data sets on multidisciplinary repository Dryad is about wood density around the world; it has been downloaded 5,700 times. Co-author Amy Zanne thinks that users probably range from climate-change researchers wanting to estimate how much carbon is stored in biomass, to foresters looking for information on different grades of timber. “I’d much prefer to have my data used by the maximum number of people to ask (heir own questions,” she says. “It’s important to allow read¬ers and reviewers to see exactly how you arrive at your results. Publishing data and code allows your science to be reproducible.”Even people whose data are less popular can benefit. By making the effort to organize and label files so others can understand them, scientists become more organized and better disciplined themselves, thus avoiding confusion later on.What do many researchers generally accept?What is the attitude of most researchers towards making their own data public?According to the passage, what might hinder open data sharing?What helps lift some of the barriers to open data sharing?Dryad serves as an example to show how open data sharing(  ).

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The Price of Oil and the Price of Carbon[A] Fossil fuel prices are likely to stay “low for long.” Notwithstanding important recent progress in de¬veloping renewable fuel sources, low fossil fuel prices could discourage further innovation in, and adoption of, cleaner energy technologies. The result would be higher emissions of carbon dioxide and other greenhouse gases.[B] Policymakers should not allow low energy prices to derail the clean energy transition. Action to re¬store appropriate price incentives, notably through corrective carbon pricing, is urgently needed to lower the risk of irreversible and potentially devastating effects of climate change. That approach al¬so offers fiscal benefits.[C] Oil prices have dropped by over 60% since June 2014. A commonly held view in the oil industry is that “the best cure for low oil prices is low oil prices.” The reasoning behind this saying is that low oil prices discourage investment in new production capacity, eventually shifting the oil supply curve backward and bringing prices back up as existing oil fields—which can be tapped at relatively low marginal cost一are depleted. In fact, in line with past experience, capital expenditure in the oil sec¬tor has dropped sharply in many producing countries, including the United States. The dynamic ad¬justment to low oil prices may, however, be different this time around.[D] Oil prices are expected to remain lower for longer. The advent of new technologies has added about 4.2 million barrels per day to the crude oil market, contributing to a global over-supply. In addition, other factors are putting downward pressure on oil prices: change in the strategic behavior of the Organization of Petroleum Exporting Countries, the projected increase in Iranian exports, the scaling- down of global demand (especially from emerging markets), the long-term drop in petroleum con¬sumption in the United States, and some displacement of oil by substitutes. These likely persistent forces, like the growth of shale (页岩)oil, point to a "low for long” scenario. Futures markets, which show only a modest recovery of prices to around $60 a barrel by 2019, support this view.[E] Natural gas and coal—also fossil fuels—have similarly seen price declines that look to be long-lived. Coal and natural gas are mainly used for electricity generation, whereas oil is used mostly to power transportation, yet the prices of all these energy sources are linked. The North American shale gas boom has resulted in record low prices there. The recent discovery of the giant Zohr gas field off the Egyptian coast will eventually have impact on pricing in the Mediterranean region and Europe, and there is significant development potential in many other places, notably Argentina. Coal prices also are low, owing to over-supply and the scaling-down of demand, especially from China, which bums half of the world’s coal.[F ] Technological innovations have unleashed the power of renewables such as wind, hydro, solar, and geothermal (地热).Even Africa and the Middle East, home to economies that are heavily dependent on fossil fuel exports, have enormous potential to develop renewables. For example, the United Arab Emirates has endorsed an ambitious target to draw 24% of its primary energy consumption from re¬newable sources by 2021.[G] Progress in the development of renewables could be fragile, however, if fossil fuel prices remain low for long. Renewables account for only a small share of global primary energy consumption, which is still dominated by fossil fuels一30% each for coal and oil, 25% for natural gas. But renewable energy will have to displace fossil fuels to a much greater extent in the future to avoid unacceptable climate risks.[H] Unfortunately, the current low prices for oil, gas, and coal may provide little incentive for research to find even cheaper substitutes for those fuels. There is strong evidence that both innovation and adoption of cleaner technology are strongly encouraged by higher fossil fuel prices. The same is true for new technologies for alleviating fossil fuel emissions.[I] The current low fossil fuel price environment will thus certainly delay the energy transition from fos¬sil fuel to clean energy sources. Unless renewables become cheap enough that substantial carbon deposits are left underground for a very long time, if not forever, the planet will likely be exposed to potentially catastrophic climate risks.[J] Some climate impacts may already be discernible. For example, the United Nations Children's Fund estimates that some 11 million children in Africa face hunger, disease, and water shortages as a re¬sult of the strongest El Nino (厄尔尼诺)weather phenomenon in decades. Many scientists believe that El Nino events, caused by warming in the Pacific, are becoming more intense as a result of climate change.[K] Nations from around the world have gathered in Paris for the United Nations Climate Change Con¬ference, COP 21, with the goal of a universal and potentially legally-binding agreement on reducing greenhouse gas emissions. We need very broad participation to fully address the global tragedy that results when countries fail to take into account the negative impact of their carbon emissions on the rest of the world. Moreover, non-participation by nations, if sufficiently widespread, can undermine the political will of participating countries to act.[L] The nations participating at COP 21 are focusing on quantitative emissions-reduction commitments. Economic reasoning shows that the least expensive way for each country is to put a price on car¬bon emissions. The reason is that when carbon is priced, those emissions reductions that are least costly to implement will happen first. The International Monetary Fund calculates that countries can generate substantial fiscal revenues by eliminating fossil fuel subsidies and levying carbon charges that capture the domestic damage caused by emissions. A tax on upstream carbon sources is one easy way to put a price on carbon emissions, although some countries may wish to use other meth¬ods, such as emissions trading schemes. In order to maximize global welfare, every country’s carbon pricing should reflect not only the purely domestic damage from emissions, but also the damage to foreign countries.[M] Setting the right carbon price will therefore efficiently align the costs paid by carbon users with the true social opportunity cost of using carbon. By raising relative demand for clean energy sources, a carbon price would also help align the market return to clean-energy innovation with its social re¬turn, spurring the refinement of existing technologies and the development of new ones. And it would raise the demand for technologies such as carbon capture and storage, spurring their further development. If not corrected by the appropriate carbon price, low fossil fuel prices are not accu¬rately signaling to markets the true social profitability of clean energy. While alternative estimates of the damage from carbon emissions differ, and it’s especially hard to reckon the likely costs of possi¬ble catastrophic climate events, most estimates suggest substantial negative effects.[N] Direct subsidies to research and development have been adopted by some governments but are a poor substitute for a carbon price: they do only part of the job, leaving in place market incentives to over-use fossil fuels and thereby add to the stock of atmospheric greenhouse gases without regard to the collateral (附带的)costs.[O] The hope is that the success of COP 21 opens the door to future international agreement on carbonprices. Agreement on an international carbon-price floor would be a good starting point in that process. Failure to address comprehensively the problem of greenhouse gas emissions, however, exposes all generations, present and future, to incalculable risks.

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After becoming president of Purdue University in 2013, Mitch Daniels asked the faculty to prove that their students have actually achieved one of higher education’s most important goals: critical thinking skills. Two years before, a nationwide study of college graduates had shown that more than a third had made no(  ) — gains in such mental abilities during their school years. Mr. Daniels needed to (  )  the high cost of attending Purdue to its students and their families. After all, the percentage of Ameri¬cans who say a college degree is “very important” has fallen (  )  in the last 5-6 years.Purdue now has a pilot test to assess students’ critical thinking skills. Yet like many college teachers around the U.S., the faculty remain (  )  that their work as educators can be measured by a “learning (  )   ” such as a graduate’s ability to investigate and reason. However, (he professors need not worry so much. The results of a recent experiment showed that professors can use (  )  metrics to measure how well students do in three key areas: critical thinking, written communication, and quantitative literacy.Despite the success of the experiment, the actual results are worrisome, and mostly (  )  earlier studies. The organizers of the experiment concluded that far fewer students were achieving at high levels on critical thinking than they were doing for written communication or quantitative literacy. And that conclusion is based only on students nearing graduation.American universities, despite their global (  )   for excellence in teaching, have only begun to demonstrate what they can produce in real-world learning. Knowledge-based degrees are still important, but employers are (  )  advanced thinking skills from college graduates. If the intellectual worth of a college degree can be (  )  measured, more people will seek higher education—and come out better thinkers.

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What a waste of money! In return for an average of £44,000 of debt, students get an average of only 14 hours of lecture and tutorial time a week in Britain. Annual fees have risen from £I,000 to £9,000 in the last decade, but contact time at university has barely risen at all. And graduating doesn’t even provide any guarantee of a decent job: six in ten graduates today are in non-graduate jobs.No wonder it has become fashionable to denounce many universities as little more than elaborate con-tricks (骗术..There’s a lot for students to complain about: the repayment threshold for paying back loans will be frozen for five years, meaning that lower-paid graduates have to start repaying their loans; and maintenance grants have been replaced by loans, meaning that students from poorer backgrounds face higher debt, than those with wealthier parents.Yet it still pays to go to university. If going to university doesn’t work out, students pay very little— if any—of their tuition fees back: you only start repaying when you are earning £21,000 a year. Almost half of graduates—those who go on to earn less—will have a portion of their debt written off. It’s not just the lectures and tutorials that are important. Education is the sum of what students teach each other in between lectures and seminars. Students do not merely benefit while at university; studies show they go on to be healthier and happier than non-graduates, and also far more likely to vote.Whatever your talents, it is extraordinarily difficult to get a leading job in most fields without having been to university. Recruiters circle elite universities like vultures (兀鹰..Many top firms will not even look at applications from those who lack a 2.1, i.e., an upper-second class degree, from an elite university. Students at university also meet those likely to be in leading jobs in the future, forming contacts for life. This might not be right, but school-leavers who fail to acknowledge as much risk making the wrong decision about going to university.Perhaps the reason why so many universities offer their students so little is they know studying at a top university remains a brilliant investment even if you don't learn anything. Studying at university will only become less attractive if employers shift their focus away from where someone went to university— and there is no sign of that happening anytime soon. School-leavers may moan, but they have little choice but to embrace university and the student debt that comes with it.What is the author’s opinion of going to university?What does the author say about the employment situation of British university graduates?What does the author say is important for university students besides classroom instruction?What is said to be an advantage of going to university?What can we infer from the last paragraph?

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Any veteran nicotine addict will testify that fancy packaging plays no role in the decision to keep smoking. So, it is argued, stripping cartons of their branding will trigger no mass movement to quit.But that isn’t why the government—under pressure from cancer charities, health workers and the Labour party—has agreed to legislate for standardised packaging. The theory is that smoking should be stripped of any appeal to discourage new generations from starting in the first place. Plain packaging would be another step in the reclassification of cigarettes from inviting consumer products to narcotics (麻醉剂).Naturally, the tobacco industry is violently opposed. No business likes to admit that it sells addictive poison as a lifestyle choice. That is why government has historically intervened, banning advertising, imposing health warnings and punitive (惩罚性的.duties. This approach has led over time to a fall in smoking with numbers having roughly halved since the 1970s. Evidence from Australia suggests plain packaging pushes society further along that road. Since tobacco is one of the biggest causes of premature death in the UK, a measure that tames the habit even by a fraction is worth trying.So why has it taken so long? The Department of Health declared its intention to consider the move in November 2010 and consulted through 2012. But the plan was suspended in July 2013. It did not escape notice that a lobbying Finn set up by Lynton Crosby, David Cameron’s election campaign director, had previously acted for Philip Morris International. (The prime minister denied there was a connection between his new adviser’s outside interests and the change in legislative programme.. In November 2013, after an unnecessary round of additional consultation, health minister Jane Ellison said the government was minded to proceed after all. Now we are told Members of Parliament (MPs. will have a free vote before parliament is dissolved in March.Parliament has in fact already authorised the government to tame the tobacco trade. MPs voted overwhelmingly in favour of Labour amendments to the children and families bill last February that included the power to regulate for plain packaging. With sufficient will in Downing Street this would have been done already. But strength of will is the missing ingredient where Mr. Cameron and public health are concerned. His attitude to state intervention has looked confused ever since his bizarre 2006 lament (叹惜.that chocolate oranges placed seductively at supermarket checkouts fueled obesity.The government has moved reluctantly into a sensible public health policy, but with such obvious over-cautiousness that any political credit due belongs to the opposition. Without sustained external pressure it seems certain Mr. Cameron would still be hooked on the interests of. big tobacco companies.What do chain smokers think of cigarette packaging?What has the UK government agreed to do concerning tobacco packaging?What has happened in Australia where plain packaging is implemented?Why has it taken so long for the UK government to consider plain packaging?What did Cameron say about chocolate oranges at supermarket checkouts?

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Countries Rush for Upper Hand in Antarctica[A] On a glacier-filled island with fjords (峡湾)and elephant seals, Russia has built Antarctica’s first Orthodox church on a hill overlooking its research base. Less than an hour away by snowmobile, Chinese labourers have updated the Great Wall Station, a vital part of China’s plan to operate five bases on Antarctica, complete with an indoor badminton court and sleeping quarters for 150 people. Not to be outdone, India’s futuristic new Bharathi base, built on stilts (桩子)using 134 interlocking shipping containers, resembles a spaceship. Turkey and Iran have announced plans to build bases, too.[B] More than a century has passed since explorers raced to plant their flags at the bottom of the world, and for decades to come this continent is supposed to be protected as a scientific preserve, shielded from intrusions like military activities and mining. But an array of countries are rushing to assert greater influence here, with an eye not just towards the day those protective treaties expire, but also for the strategic and commercial opportunities that already exist.[C] The newer players are stepping into what they view as a treasure house of resources. Some of the ventures focus on the Antarctic resources that are already up for grabs, like abundant sea life. South Korea, which operates state-of-the-art bases here, is increasing its fishing of krill (磷虾),found in abundance in the Southern Ocean, while Russia recently frustrated efforts to create one of the world’s largest ocean sanctuaries here.[D] Some scientists are examining the potential for harvesting icebergs from Antarctica, which is estimated to have the biggest reserves of fresh water on the planet. Nations are also pressing ahead with space research and satellite projects to expand their global navigation abilities.[E] Building on a Soviet-era foothold, Russia is expanding its monitoring stations for Glonass, its version of the Global Positioning System (GPS). At least three Russian stations are already operating in Antarctica, part of its effort to challenge the dominance of the American GPS, and new stations are planned for sites like the Russian base, in the shadow of the Orthodox Church of the Holy Trinity.[F] Elsewhere in Antarctica, Russian researchers boast of (heir recent discovery of a freshwater reserve the size of Lake Ontario after drilling through miles of solid ice. “You can see that we’re here to stay,” said Vladimir Cheberdak, 57, chief of the Bellingshausen Station, as he sipped tea under a portrait of Fabian Gottlieb von Bellingshausen, a high-ranking officer in the Imperial Russian Navy who explored the Antarctic coast in 1820.[G] Antarctica’s mineral, oil and gas wealth are a longer-term prize. The treaty banning mining here, shielding coveted (令人垂涎的)reserves of iron ore, coal and chromium, comes up for review in 2048. Researchers recently found kimberlite (金伯利岩)deposits hinting at the existence of diamonds. And while assessments vary widely, geologists estimate that Antarctica holds at least 36 billion barrels of oil and natural gas.[H] Beyond the Antarctic treaties, huge obstacles persist to tapping these resources, like drifting icebergs that could jeopardise offshore platforms. Then there is Antarctica’s remoteness, with some mineral deposits found in windswept locations on a continent that is larger than Europe and where winter temperatures hover around minus 55 degrees Celsius.[I] But advances in technology might make Antarctica a lot more accessible three decades from now. And even before then, scholars warn, the demand for resources in an energy-hungry world could raise pressure to renegotiate Antarctica’s treaties, possibly allowing more commercial endeavours here well before (he prohibitions against them expire. The research stations on King George Island offer a glimpse into the long game on this ice-blanketed continent as nations assert themselves, eroding the sway long held by countries like the United States, Britain, Australia and New Zealand.[J] Being stationed in Antarctica involves adapting to life on the planet’s driest, windiest and coldest continent, yet each nation manages to make itself at home. Bearded Russian priests offer regular services at the Orthodox church for the 16 or so Russian speakers who spend the winter at the base, largely polar scientists in fields like glaciology and meteorology. Their number climbs to about 40 in the warmer summer months. China has arguably the fastest-growing operations in Antarctica. It opened its fourth station last year and is pressing ahead with plans to build a fifth. It is building its second ice-breaking ship and setting up research drilling operations on an ice dome 13,422 feet above sea level that is one of the planet’s coldest places. Chinese officials say the expansion in Antarctica prioritises scientific research, but they also acknowledge that concerns about “resource security” influence their moves.[K] China’s newly renovated Great Wall Station on King George Island makes the Russian and Chilean bases here seem outdated. "We do weather monitoring here and other research,” Ning Xu, 53, the chief of the Chinese base, said over tea during a fierce blizzard (暴风雪)in late November. The large base he leads resembles a snowed-in college campus on holiday break, with the capacity to sleep more than 10 times the 13 people who were staying on through the Antarctic winter. Yong Yu, a Chinese microbiologist, showed off the spacious building, with empty desks under an illustrated timeline detailing the rapid growth of China's Antarctic operations since the 1980s. “We now feel equipped to grow,” he said.[L] As some countries expand operations in Antarctica, the United States maintains three year-round stations on the continent with more than 1,000 people during the southern hemisphere’s summer, including those at. the Amundsen-Scott station, built in 1956 at an elevation of 9,301 feet on a plateau at the South Pole. But US researchers quietly complain about budget restraints and having far fewer icebreakers than Russia, limiting the reach of the United States in Antarctica.[M] Scholars warn that Antarctica's political drift could blur the distinction between military and civilian activities long before the continent's treaties come up for renegotiation, especially in parts of Antarctica that are ideal for intercepting (拦截)signals from satellites or retasking satellite systems, potentially enhancing global electronic intelligence operations.[N] Some countries have had a hard time here. Brazil opened a research station in 1984, but it was largely destroyed by a fire that killed two members of the navy in 2012, the same year that a diesel-laden Brazilian barge sank near the base. As if that were not enough, a Brazilian C-130 Hercules military transport plane has remained stranded near the runway of Chile’s air base here since it crash-landed in 2014.[O] However, Brazil's stretch of misfortune has created opportunities for China, with a Chinese company winning the $100 million contract in 2015 to rebuild the Brazilian station.[P] Amid all the changes, Antarctica maintains its allure. South Korea opened its second Antarctic research base in 2014, describing it as a way to test robots developed by Korean researchers for use in extreme conditions. With Russia's help, Belarus is preparing to build its first Antarctic base. Colombia said this year that it planned to join other South American nations with bases in Antarctica.[Q] “The old days of the Antarctic being dominated by the interests and wishes of white men from European, Australasian and North American states are over,” said Klaus Dodds, a politics scholar at the University of London who specialises in Antarctica. “The reality is that Antarctica is geopolitically contested.”

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Small communities, with their distinctive character—where life is stable and intensely human一are disappearing. Some have(  ) from the face of the earth, others are dying slowly, but all have (  ) hanges as they have come into contact with an (  ) machine civilization. The merging of diverse peoples into a common mass has produced tension among members of the minorities and the majority alike.The Old Order Amish, who arrived on American shores in colonial times, have (  ) in the modem world in distinctive, small communities. They have resisted the homogenization(  )ore successfully than others. In planting and harvest time one can see their bearded men working the fields with horses and their women hanging out the laundry in neat rows to dry. Many American people have seen Amish families, with the men wearing broad-brimmecl black hats and the women in long dresses, in railway or bus (  ) . Although the Amish have lived with (  )America for over two and a half centuries, they have moderated its influence on their personal lives, their families, communities, and their values.The Amish are often (  ) by other Americans to be relics of the past who live a simple, inflexible life dedicated to inconvenient out-dated customs. They are seen as abandoning both modem (  ) and the American dream of success and progress. But most people have no quarrel with the Amish for doing things the old-fashioned way. Their conscientious objection was tolerated in wartime, for after all, they are good farmers who (  ) the virtues of work and thrift.

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More than 100 years ago, American sociologist W. E. B. Du Bois was concerned that race was being used as a biological explanation for what he understood to be social and cultural differences between different populations of people. He spoke out against the idea of “white” and “black” as distinct groups, claiming that these distinctions ignored the scope of human diversity.Science would favor Du Bois. Today, the mainstream belief among scientists is that race is a social construct without biological meaning. In an article published in the journal Science, four scholars say racial categories need to be phased out.“Essentially, I could not agree more with the authors,M said Svante Paabo, a biologist and director of the Max Planck Institute for Evolutionary Anthropology in Germany. In one example that demonstrated genetic differences were not fixed along racial lines, the full genomes (基因组.of James Watson and Craig Venter, two famous American scientists of European ancestry, were compared to that of a Korean scientist, Seong-Jin Kim. It turned out that Watson and Venter shared fewer variations in their genetic sequences than they each shared with Kim.Michael Yudell, a professor of public health at Drexel University in Philadelphia, said that modem genetics research is operating in a paradox: on the one hand, race is understood to be a useful tool to illuminate human genetic diversity, but on the other hand, race is also understood to be a poorly defined marker of that diversity.Assumptions about genetic differences between people of different races could be particularly dangerous in a medical setting. “If you make clinical predictions based on somebody’s race, you’re going to be wrong a good chunk of the time,” Yudell told Live Science. In the paper, he and his colleagues used the example of cystic fibrosis, which is underdiagnosed in people of African ancestry because it is thought of as a “white” disease.So what other variables could be used if the racial concept is thrown out? Yudell said scientists need to get more specific with their language, perhaps using terms like “ancestry” or “population” that might more precisely reflect the relationship between humans and their genes, on both the individual andpopulation level. The researchers also acknowledged that there are a few areas where race as a construct might still be useful in scientific research: as a political and social, but not biological, variable.“While we argue phasing out racial terminology (术语.in the biological sciences, we also acknowledge that using race as a political or social category to study racism, although filled with lots of challenges, remains necessary given our need to understand how structural inequities and discrimination produce health disparities (差异.between groups,” Yudell said.Du Bois was opposed to the use of race as(  ).The study by Svante Piiabo served as an example to show (  ).  The example of the disease cystic fibrosis underdiagnosed in people of African ancestry demonstrates that (  ).  What is Yudell’s suggestion to scientists?What can be inferred from Yudell’s remark in the last paragraph?

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Dr. Donald Sadoway at MIT started his own battery company with the hope of changing the world’s energy future. It’s a dramatic endorsement for a technology most people think about only when their smartphone goes dark. But Sadoway isn’t alone in trumpeting energy storage as a missing link to a cleaner, more efficient, and more equitable energy future.Scientists and engineers have long believed in the promise of batteries to change the world. Advanced batteries are moving out of specialized markets and creeping into the mainstream, signaling a tipping point for forward-looking technologies such as electric cars and rooftop solar panels.The ubiquitous (无所不在的.battery has already come a long way, of course. For better or worse, batteries make possible our mobile-first lifestyles, our screen culture, our increasingly globalized world. Still, as impressive as all this is, it may be trivial compared with what comes next. Having already enabled a communications revolution, the battery is now poised to transform just about everything else.The wireless age is expanding to include not just our phones, tablets, and laptops, but also our cars, homes, and even whole communities. In emerging economies, rural communities are bypassing the wires and wooden poles that spread power. Instead, some in Africa and Asia are seeing their first lightbulbs illuminated by the power of sunlight stored in batteries.Today, energy storage is a $33 billion global industry that generates nearly 100 gigawatt-hours of electricity per year. By the end of the decade, it’s expected to be worth over $50 billion and generate 160 gigawatt-hours, enough to attract the attention of major companies that might not otherwise be interested in a decidedly pedestrian technology. Even utility companies, which have long viewed batteries and alternative forms of energy as a threat, are learning to embrace the technologies as enabling rather than disrupting.Today’s battery breakthroughs come as the world looks to expand modem energy access to the billion or so people without it, while also cutting back on fuels that warm the planet. Those simultaneous challenges appear less overwhelming with increasingly better answers to a centuries-old question: how to make power portable.To be sure, the battery still has a long way to go before the nightly recharge completely replaces the weekly trip to the gas station. A battery-powered world comes with its own risks, too. What happens to the centralized electric grid, which took decades and billions of dollars to build, as more and more people become “prosumers,” who produce and consume their own energy on-site?No one knows which—if any一battery technology will ultimately dominate, but one thing remains clear: The future of energy is in how we store it.What does Dr. Sadoway think of energy storage?What is most likely to happen when advanced batteries become widely used?In some rural communities of emerging economies, people have begun to (  ).Utility companies have begun to realize that battery technologies (  ).  What does the author imply about the centralized electric grid?

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The American Workplace Is Broken. Here’s How We Can Start Fixing It.[A] Americans are working longer and harder hours than ever before. 83% of workers say they’re stressed about their jobs, nearly 50% say work-related stress is interfering with their sleep, and 60% use their smartphones to check in with work outside of normal working hours. No wonder only 13% of employees worldwide feel engaged in their occupation.[B] Glimmers (少许)of hope, however, are beginning to emerge in this bruising environment: Americans are becoming aware of the toll their jobs take on them, and employers are exploring ways to alleviate the harmful effects of stress and overwork. Yet much more work remains to be done. To call stress an epidemic isn’t, exaggeration. The 83% of American employees who are stressed about their jobs—up from 73% just a year before一say that poor compensation and an unreasonable workload are their number-one sources of stress. And if you suspected that the workplace had gotten more stressful than it was just a few decades ago, you’re right. Stress levels increased 18% for women and 24% for men from 1983 to 2009. Stress is also starting earlier in life, with some data suggesting that today’s teens are even more stressed than adults.[C] Stress is taking a significant toll on our health, and the collective public health cost may be enormous. Occupational stress increases the risk of heart attack and diabetes, accelerates the aging process, decreases longevity, and contributes to depression and anxiety, among numerous other negative health outcomes. Overall, stress-related health problems account for up to 90% of hospital visits, many of them preventable. Your job is “literally killing you,” as The Washington Post put it. It’s also hurting our relationships. Working parents say they feel stressed, tired, rushed and short on quality time with their children, friends and partners.[D] Seven in 10 workers say they struggle to maintain work-life balance. As technology (and with it, work emails) seeps (渗入)into every aspect of our lives, work-life balance has become an almost meaningless term. Add a rapidly changing economy and an uncertain future to this 24/7 connectivity, and you’ve got a recipe for overwork, according to Phyllis Moen. “There’s rising work demand coupled with the insecurity of mergers, takeovers, downsizing and other factors,” Moen said. “Part of the work-life issue has to talk about uncertainty about the future.”[E] These factors have converged to create an increasingly impossible situation with many employees overworking to the point of burnout. It’s not only unsustainable for workers, but also for the companies that employ them. Science has shown a clear correlation between high stress levels in workers and absenteeism (旷工),reduced productivity,disengagement and high turnover. Too many workplace policies effectively prohibit employees from developing a healthy work-life balance by barring them from taking time off, even when they need it most.[F] The U.S. trails far behind every wealthy nation and many developing ones that have family-friendly work policies including paid parental leave, paid sick days and breast-feeding support, according to a 2007 study. The U.S. is also the only advanced economy that does not guarantee workers paid vacation time, and it’s one of only two countries in the world that, does not offer guaranteed paid maternity leave. But even when employees are given paid time off, workplace norms and expectations that pressure them to overwork often prevent them from taking it. Full-time employees who do have paid vacation days only use half of them on average.[G] Our modem workplaces also operate based on outdated time constraints. The practice of clocking in for an eight-hour workday is a leftover from the days of the Industrial Revolution, as reflected in the then-popular saying, “Eight hours labor, eight hours recreation, eight hours rest.”[H] We’ve held on to this workday structure—but thanks to our digital devices, many employees never really clock out. Today, the average American spends 8.8 hours at work daily, and the majority of working professionals spend additional hours checking in with work during evenings, weekends and even vacations. The problem isn’t the technology itself, but that the technology is being used to create more flexibility for the employer rather than the employee. In a competitive work environment,employers are able to use technology to demand more from their employees rather than motivating workers with flexibility that benefits them.[I] In a study published last year, psychologists coined the term “workplace telepressure” to describe an employee’s urge to immediately respond to emails and engage in obsessive thoughts about returning an email to one’s boss, colleagues or clients. The researchers found that telepressure is a major cause of stress at work, which over time contributes to physical and mental burnout. Of the 300 employees participating in the study, those who experienced high levels of telepressure were more likely to agree with statements assessing burnout, like “I’ve no energy for going to work in the morning,” and to report feeling fatigued and unfocused. Telepressure was also correlated with sleeping poorly and missing work.[J] Harvard Business School professor Leslie Perlow explains that when people feel the pressure to be always “on,” they find ways to accommodate that pressure, including altering their schedules, work habits and interactions with family and friends. Perlow calls this vicious cycle the “cycle of respon¬siveness": Once bosses and colleagues experience an employee’s increased responsiveness, they in¬crease their demands on the employee’s time. And because a failure to accept these increased de¬mands indicates a lack of commitment to one’s work, the employee complies.[K] To address skyrocketing employee stress levels, many companies have implemented workplace wellness programs, partnering with health care providers that have created programs to promote employee health and well-being. Some research does suggest that these programs hold promise. A study of employees at health insurance provider Aetna revealed that roughly one quarter of those taking in-office yoga and mindfulness classes reported a 28% reduction in their stress levels and a 20% improvement in sleep quality. These less-stressed workers gained an average of 62 minutes per week of productivity. While yoga and meditation (静思.are scientifically proven to reduce stress levels, these programs do little to target the root causes of burnout and disengagement. The conditions creating the stress are long hours, unrealistic demands and deadlines, and work-life conflict.[L] Moen and her colleagues may have found the solution. In a 2011 study, she investigated the effects of implementing a Results Only Work Environment (ROWE. on the productivity and well-being of employees at Best Buy’s corporate headquarters.[M] For the study, 325 employees spent six months taking part in ROWE, while a control group of 334 employees continued with their normal workflow. The ROWE participants were allowed to freely determine when, where and how they worked—the only thing that mattered was that they got the job done. The results were striking. After six months, the employees who participated in ROWE reported reduced work-family conflict and a better sense of control of their time, and they were getting a full hour of extra sleep each night. The employees were less likely to leave their jobs, resulting in reduced turnover. It’s important to note that the increased flexibility didn’t encourage them to work around the clock. “They didn’t work anywhere and all the time—they were better able to manage their work,” Moen said. “Flexibility and control is key,” she continued.

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Teenagers at risk of depression, anxiety and suicide often wear their troubles like a neon (霓虹灯. sign. Their risky behaviors—drinking too much alcohol, using illegal drugs, smoking cigarettes and skip¬ping school—can alert parents and teachers that serious problems are brewing.But a new study finds that there’s another group of adolescents who are in nearly as much danger of experiencing the same psychiatric symptoms: teens who use tons of media, don’t get enough sleep and have a sedentary (不爱活动的. lifestyle.Of course, that may sound like a description of every teenager on the planet. But the study warns that it is teenagers who engage in all three of these practices in the extreme who are truly in jeopardy. Because their behaviors are not usually seen as a red flag, these young people have been dubbed the “invisible risk” group by the study’s authors.“In some ways they’re at greater risk of falling through the cracks,” says researcher Vladimir Carli. “While most parents, teachers and clinicians would react to an adolescent using drugs or getting drunk, they may easily overlook teenagers who are engaging in inconspicuous behaviors.”The study’s authors surveyed 12,395 students and analyzed nine risk behaviors, including excessive alcohol use, illegal drug use, heavy smoking, high media use and truancy (逃学..Their aim was to de¬termine the relationship between these risk behaviors and mental health issues in teenagers.About 58% of the students demonstrated none or few of the risk behaviors. Some 13% scored high on all nine of the risk behaviors. And 29%, the “invisible risk” group, scored high on three in particular: They spent five hours a day or more on electronic devices. They slept six hours a night or less. And they neglected “other healthy activities.”The group that scored high on all nine of the risk behaviors was most likely to show symptoms of depression; in all, nearly 15% of this group reported being depressed, compared with just 4% of the low- risk group. But the invisible group wasn't far behind the high-risk set, with more than 13% of them ex¬hibiting depression.The findings caught Carli off guard. “We were very surprised," he says. “The high-risk group and low-risk group are obvious. But this third group was not only unexpected, it was so distinct and so large—nearly one third of our sample—that it became a key finding of the study."Carli says that one of the most significant things about his study is that it provides new early-warn¬ing signs for parents, teachers and mental health-care providers. And early identification, support and treatment for mental health issues, he says, are the best ways to keep them from turning into full-blown disorders.What does the author mean by saying “Teenagers at risk of depression, anxiety and suicide often wear their troubles like a neon sign” (Lines 1-2, Para. 1.?What is the finding of the new study?Why do the researchers refer to teens who use tons of media, don't get enough sleep and have a sedentary lifestyle as the “invisible risk” group?What does the new study find about the invisible group?What is the significance of Vladimir Carli’s study?

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