Scientists have identified the likely culprit in a disease that has devastated sea stars along the west coast of North America. Genomic detective work and lab experiments show that the wasting disorder is associated with a previously unknown virus. With the discovery comes a deeper mystery, however, the sea star—killing virus is far from new. The authors of the study found it in museum samples up to 72 years old, so scientists are puzzled about why the current outbreak has been so severe. “This is probably the most extensive and devastating disease of marine invertebrates that has happened,“ says ecologist Bruce Mange of Oregon State University, Corvallis, who was not involved in the new research. “It’s a major concern. “ The enigmatic disease came to broad attention in June 2013, when recreational divers near Vancouver, British Columbia, and Seattle, Washington, began noticing legions of dying sea stars. The sea stars first developed lesions, then began to lose their arms, and finally decayed into piles of skeletal ossicles(bits of calcium carbonate such as a star’s plates and spines). As the year progressed , the disease was seen in more and more locations in the waters off California. [*] Although there have been minor outbreaks in previous decades , this one is much more widespread, and more than 20 species of sea stars have been afflicted: other kinds of echino-derms, the animal group to which sea stars and sea urchins belong, have not. Researchers have raced to collect samples and conduct laboratory experiments to investigate any pathogens that might be involved. A feature in Science earlier this year, now available for free, examined the mystery. Scientists sent hundreds of tissue samples to Ian Hewson, a microbial oceanographer at Cornell University. When he sequenced the DNA in the samples, he discovered that a densovirus was more common in the sick stars than in ones that looked healthy.(Densoviruses are known to infect insects, crustaceans, and some sea urchins.)Additional evidence came from experiments conducted by marine ecologist Drew Harvell of Cornell and other researchers, who took tissue from sick sea stars, filtered out everything larger than viruses, and injected the tissue into apparently healthy sea stars. They developed symptoms—and, concurrently, the amount of densovirus in their bodies increased. Other sea stars injected with sterilized tissue did not develop symptoms of the wasting disorder. “We have very good evidence that this is a densovirus,“ Hewson says. But because the virus cannot be grown in culture, scientists cannot satisfy the classic tests for identifying the culprit of a disease: four criteria collectively referred to as Koch’s postulates. The researchers published their results online today in the Proceedings of the National Academy of Sciences. Looking for some historical perspective, Hewson tested museum samples of sea stars collected between 1923 and 2010 along the US west coast. The virus existed in healthy-looking specimens from five different years, suggesting it has persisted in the environment. Hewson speculates that the virus may have mutated as it wiped out various species of sea stars, allowing it to infect others. He is also trying to figure out the source of the virus, by analyzing sea stars from around the world, and whether it can infect other kinds of echinoderms. The biggest question is why the current epidemic has been so bad. A likely situation, Hewson and his colleagues say, is that an overabundance of sea stars increased the transmission of the virus, especially if they were stressed by competition for food, which could make them more vulnerable to infection. That theory makes sense to marine pathologist Marta Gomez-Chiarri of the University of Rhode Island, Kingston, who was not involved in the new paper. She and her students have been studying an earlier densovirus outbreak on the east coast: populations of sea stars in Rhode Island’s Narra-gansett Bay abounded before a crash in 2011. It’s not clear whether the same densovirus that caused the west coast die-off is also involved in the eastern declines. Hewson found some densovirus genes in sea stars from Connecticut but did not have enough samples for firm conclusions. Menge doesn’t think overabundance played a role in the current outbreak among 13 sea star populations that he follows on the coast of Oregon. Instead, he wonders whether ocean acidification, which may also be a source of stress that weakens sea stars, is a possible contributing factor. So far, the evidence is mixed for the role of acidification, Mange admits. Whatever the cause of the epidemic, Mange says, the demise of purple stars has already led to greater survival of its prey, including barnacles and mussels. As a result, he predicts, the mussels will eventually take over the rocky shore, crowding out many other species of invertebrates. In a way, he adds, the epidemic is a once-in-a-lifetime opportunity for ecologists to study these predator-prey relationships. But that doesn’t dull the pain of losing familiar and charismatic species. “ From a personal standpoint, it’s really disheartening. “ Questions 56 to 60 Mark each statement as either true(T)or false(F)according to the passage.

Read the following passage. Choose from the sentences A-G the one which best fits each gap of 61 —65. There are two extra sentences which you do not need to use. A Dutch Sinologist has spent more than 50 years studying the country’s language, and classic literature. 【R1】______As a child, the vivid descriptions of China in Nobel and Pulitzer Prize-winner Pearl S. Buck’s books sparked Idema’s interest in the country. He later read classic Chinese literature and spent whole days pouring through works at the National Library of China. The 70-year-old Dutch Sinologist recalled his half-century-long romance with Chinese culture during a recent visit to Beijing. Idema was the only Sinologist invited this year to participate in the Oriental Culture Research Program, an annual project hosted by the China International Culture Association. Idema has served as the director of the Chinese Languages and Cultures Department at Leiden University of the Netherlands and was also director of Harvard’s Fairbank Center for East Asian Research.【R2】______ Idema began learning Mandarin during middle school, because he wanted to learn a language that “has a long history yet is still active today“. “ Back then, I knew little about China,“ says Idema, whose early influences include Dutch Sinologist and author Robert van Gulik. 【R3】______Finding opportunities to practice the language at the school was a huge challenge. “There were actually no Chinese-speaking teachers in our university at the time, and it was also impossible for us to study in China for political reasons,“ he explains. “ So when I graduated from college, I couldn’t even speak a single sentence in Chinese, though I was able to read and write in it fluently. “ 【R4】______Idema discovered his passion for traditional Chinese plays after a Japanese professor introduced him to some works from the Yuan Dynasty(1271-1368). He soon began translating them into Western languages. Idema says it took him some time to really appreciate the poetic lyrics in the plays, which are closely associated with traditional Chinese poetry and have high aesthetic value. Idema first visited China in 1978. As one of the few Westerners who understood Chinese language and culture, he was invited to work as a guide and interpreter for a tourist delegation. While he recalls the backwardness of China in the late 1970s, Idema says he is impressed with the rapid development of the country over the last few decades. He has visited the county several times to study and teach. He vividly remembers the “ China mania“ in the West when the country opened up in the 1980s, and the flood of new materials about ancient Chinese culture that appeared in the West. 【R5】______ “ There were scholars studying law, religion and society, but not traditional Chinese literature, which was my personal interest,“ Idema explains. Finding reference books for his research, especially regional publications, used to be a huge challenge , and Idema used to spend a lot of time collecting books and other materials during visits to China. “With the internet now, it is much more convenient,“ says Idema. “Traditional Chinese culture is a passion. I have been studying it for 50 years and will continue to do so,“ says the retired professor. Questions 61 to 65 A. Idama later studied Chinese culture at Leiden University. B. In recent years, he has devoted himself to translating Chinese folk tales and writing about Chinese folk society and folk culture. C. While many other experts on China focused on the country’s economic transformation, Idema continued to study traditional Chinese literature. D. For Wilt Idema, books are the best guides in life. E. He has studied ancient Chinese plays, novels and literature, and has authored or translated a number of influential books published in English and other languages. F. Idema usually chooses less-known subjects for his research and tries to get firsthand materials. G. Idema continued his academic pursuits in Japan, where he became familiar with the similarities between the Japanese and Chinese languages.

New research points to a biological role in criminality. The tattoo on the ex-con’s beefy arm reads: Born to raise hell. Much as it may defy the science of the past, which blamed crime on the social influences such as poverty and bad parenting, the outlaw may be onto something. Though no one would deny that upbringing and environment play important parts in the making of a criminal, scientists increasingly suspect that biology also plays a significant role. Poverty and family problems, sex-role expectations, community standards—all may predispose individuals toward crime. But many researchers now believe that the reason one individual commits a crime and another person doesn’t may have as much to do with neurological differences as it does with differences in upbringing or environment. [*] After all, says Dr. Tames Q. Wilson, a professor of management and public policy at UCLA, “it’s hard to find any form of behavior that doesn’t have some biological component. “ After evaluating recent research on violence, a special panel gathered by the National Research Council(NRC)in Washington published a lengthy report last fall noting that “ even if two individuals could be exposed to identical experiences, their potentials for violent behavior would differ because their nervous systems process information differently“. First and most obvious among the clues that biology plays a role in criminal behaviors is the simple fact that throughout history, crime has occurred in all cultures. One element in the universality of crime is the human capacity for aggression. Nobel prizewinning ethnologist Konrad Lorenz, author of On Aggression, argued that just as people have an instinct for eating and drinking, nature evolved in them the impulse for aggression. Though Lorenz thought it was peculiar to people and rats, aggression has now been observed in every vertebrate species studied. In people, only a fine line separates aggression from violence—defined by researchers as behavior intended to inflict harm on others. “Criminals are, on the whole, angry people,“ says Harvard psychologist Richard Hern-stein. “That is well substantiated. “ Another simple fact pointing to a biological basis for criminality is that in all societies, about 90% of violent criminals are men—many of them young. The great majority of other crimes are also committed by men. Among animals too, the male is almost always more aggressive. This fact suggests that certain hormones, particularly androgens, which characterize maleness, may help tip the balance from obeying to breaking the law. While there’s no such thing as a “crime gene“ , or indeed any single determinant that leads a person to break the law, each child is born with a particular temperament, or characteristic pattern of psychological response. As Wilson notes, “One is shy, the other hold: one sleeps through the night, the other is always awake: one is curious and exploratory, the other passive. These observations are about differences that cannot be explained wholly or even largely by environment. “ Linking an individual’s temperament to criminality is, of course, a much more contentious matter. To search for the roots of violence, the members of the NRC panel asked several key questions. Why do some children show patterns of unusually aggressive behavior—hitting, kicking, biting peers or parents, or being cruel to animals—at an early age? Why do only a small percentage of those children commit violent crimes as adults? The panel concluded: “Research strongly suggests that violence arises from interactions among individuals’ psychological development, their neurological and hormonal differences, and social processes. “ There is no basis, the researchers added, for giving one of these elements more weight than another. Nonetheless, two camps have emerged to debate whether criminality is influenced more by nature(biology)or nurture(environment). And this is no mere ivory tower question. Public interest mounts with the statistics: Some 35 million offenses against people or households ,20% of them violent, are reported in the US every year. Research that may help resolve this nature-nurture question focuses mostly on three areas: biochemical imbalances, genetic factors and physical damage such as head injury around time of birth. Some studies suggest a link between behaviors—particularly the violent sort—and birth-related trauma , premature birth or low birth weight. Similarly, a woman’s use of alcohol, cocaine, tobacco or other drugs during pregnancy also appears, in some instances, to damage fetal development in a way that is related to later criminality. On a more positive note, however, one recent study concluded that when children who’d had a traumatic birth grew up in a stable family environment, they were no likelier than anyone else to develop into criminals. Questions 66 to 70 Answer the following questions with the information given in the passage.

A team of scientists has just finished what might literally be described as one of the most breathtaking jobs in the world — surveying and mapping the coral reefs in Southeast Asia’s Coral Triangle off the coast of Indonesia’s Sulawesi Island. As part of the Catlin Seaview Survey, teams from the University of Queensland, Indonesia’s Sam Ratulangi University and Indonesia’s Institute of Sciences spent time underwater over several weeks near the city of Manado to record data and map reefs in what the survey says “ could become one of the last refuges on Earth for coral reefs“. [*] The effort was part of a larger project to map the Coral Triangle, which encompasses 647 million hectares of land and sea located within the territories of Indonesia, Malaysia, the Philippines, Papua New Guinea, the Solomon Islands and Timor-Leste. “Coral Triangle“ refers to a roughly triangular shape of waters between the Pacific and Indian oceans. As one of the world’s most crucial breeding grounds for marine biodiversity, it’s home to 75 percent of all known coral species, including nearly 600 species of reel-building corals and 3, 000 species of reef fish. The Catlin Seaview Survey says the scale of its undersea mapping project is unprecedented. Located on the island of Sulawesi, Manado is the capital of Indonesia’s North Sulawesi province. Coral devastation According to experts, about 40 percent of the world’s corals have been lost in the last three decades due to climate change and human activities. Assuming the current rate of decline remains steady, some marine biologists predict that most of the world’s remaining coral will disappear by the middle of the century. The Catlin Seaview Survey got underway in September 2012 on Australia’s Great Barrier Reef. Centring on the waters of Southeast Asia, the 2014 campaign commenced in April has also covered areas around Apo Island and Tubbataha Reefs in the Philippines, Komodo and Bali in Indonesia, and East Timor. Located in the centre of the Coral Triangle, Manado is a crucial section for researchers. “ Regions like Manado in the Coral Triangle could, by the middle of the century, be one of the only places on Earth where coral reefs will exist,“ says Ove Hoegh-Guldberg, chief scientist of the survey and director of the Global Change Institute at the University of Queensland. “ Understanding the structure and function of such reefs is of the utmost importance if we are to underpin their resilience to global change. “ “This information is necessary to make informed decisions about how much, and where, governments should invest to ensure the future well-being of our planet,“ says Stephen Catlin, chief executive of Catlin Group Limited, a Bermuda-based insurance company that sponsors the survey. How coral reef maps are made The coral mapping effort employs a Seaview SVII underwater camera, which has a rod and propeller attached to the back to create a sort of photo scooter. Three digital SLR cameras encased in the SVII’s globe-shaped lens capture high resolution, 360 degree images of reefs. Designed by Catlin Seaview Survey, the camera’s new technology helps shorten surveying time of large, shallow water areas from months to days. To map such a vast area, scientist-divers took photographs while “riding“ the camera at an average depth of eight meters while traveling at 4kph(Kilometers per Hour). Thousands of images will eventually be stitched together to create a whole picture of the reef system. The images will be uploaded for viewing on the company’s database—the Global Reef Record. Some of the images can be found on Google Maps. Questions 56 to 60 Mark each statement as either true(T)or false(F)according to the passage.

Given their role in the 2008 meltdown, and their subsequent branding as toxic sludge, it is not surprising that “ secu-ritized“ financial products have had a quiet few years. Yet the transformation of mortgages, credit-card debt and other recurring cash flows into new marketable securities is enjoying something of resurgence. Once apparently destined for the financial history books, the alphabet soup of ABSS(asset backed securities), MBSS(their mortgage version), CLOs(collateralized loan obligations)and others had a bumper year in 2013. More growth is expected next year. [*] Not everybody is thrilled. Some observers argue that the risks securitization poses are too grave. But its revival should be welcomed, for it is probably essential to continued economic recovery, particularly in Europe. Use carefully In its simplest form, securitization is straightforward and beneficial. For example, a carmaker expecting lots of monthly payments from customers who have taken out financing can get investors to fund its business more cheaply by selling them its claim to those payments. A bank on the receiving end of mortgage repayments or credit-card receivables can do something similar: bundle the loans up and sell them, or use them as collateral to get funding, which it can then use to issue more loans. This boosts both credit and growth. Used recklessly, though, securitization can be dangerous. It fuelled the catastrophic boom in American subprime mortgages. Some banks, aware that home loans would be sliced, diced, repackaged and sold on, gave up even cursory checks on their borrowers’ creditworthiness. Investors piled in blindly, snapping up supposedly safe “tranches“ of bundled-up debt that proved to be anything but. The boom turned to bust and bail-outs. Yet structured finance cannot bear sole responsibility for the crisis. It was more the conduit for irrational financial exuberance than its cause. Lax lending standards in boom times predate the e-mergence of securitization(in the 1970s)by several centuries at least. Most structured products performed well through the crisis, with the notable exception of those related to American residential mortgages. Default in Europe remained low despite the recession. And although there are still risks, securitization should be safer in the future than in the past because of new, post-crisis regulations to reduce the danger of excesses. The principle that the party creating a new security needs to retain some exposure to the underlying credit(the “ skin in the game“ rule)should help ensure that underwriting standards do not get too slack. That will hamper the desirable transferring of risks but, given recent history, it is probably prudent to put a little sand in the gears. Europe stands to benefit most from securitization’s return. Lenders across Europe are under pressure to improve the ratio of capital they hold to loans made. One way of doing this is to stop extending credit, which is, unfortunately, what many banks have done. If they instead slimmed themselves through securitization, by bundling and repackaging loans and selling them to outside investors such as insurance firms or asset managers, they could lend more money to credit-starved companies. That would have the added benefit of spreading risk away from wobbly banks. Securitization certainly has a black mark against it, but it is far too useful to be banished for good. Almost all financial innovations, from the humble mortgage to the joint-stock company, have had to re-establish their reputation after a bust at some point in their history. Society benefited from their eventual rehabilitation—as it most probably will from the revival of securitization. Questions 71 to 75 Complete the summary below with information from the passage, using no more than three words for each blank. Securitization regains public attention along with the transformation of mortgages, credit-card debt and other recurring cash flows into new marketable securities. However, some researchers adopt a conservative attitude towards its【E1】______ , which poses great risks on economy. But securitization is stilled supported for its potential promotion of【E2】______. In its simplest form, securitization is straightforward and beneficial. It boosts both credit and growth. If used recklessly, securitization can be dangerous. For example, it has brought about a harmful effect on American subprime mortgages. Although there is still disagreement on securitization, it should be safer in the future than in the past due to the【E3】______of the danger of excesses under the control of new regulations. It is far too useful to be【E4】______for good. Almost all financial innovations, from the humble mortgage to the joint-stock company, have had to re-establish their reputation after a bust at some point in their history.【E5】______benefited from their eventual rehabilitation—as it most probably will from the revival of securitization.

Research on genes shows that the wasting disorder which destroys sea stars may be caused by an unknown but not new virus.

The sea stars near Vancouver, British Columbia, Seattle and Washington were noticed dying. They first developed lesions, then decayed into piles of skeletal ossicles and lost their arms at last.

Known as viruses that infect insects, crustaceans, and some sea urchins, densoviruses are found more common in the sick stars than in ones that looked healthy.

Researchers are curious about why the disease has spread so quickly and some propose that the sharp increase of sea stars brings fiercer competition for food among these creatures, which fastens the transmission of viruses and leaves sea stars exposed to infection.

Menge thinks that ocean acidification plays a role in weakening sea stars and the evidence has turned out conclusive.