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Fishermen on the high seas have plenty of worries, not the least of which are boat-tossing storms, territorial squabbles and even pirates. Now Boris Worm, a marine biologist at Dalhousie University in Halifax, Canada, has added another. After studying, among other things, global catch data over more than 50 years, he and a team of 13 researchers in four countries have come to a stunning conclusion. By the middle of this century, fishermen will have almost nothing left to catch. "None of us regular working folk are going to be able to afford seafood," says Stephen Palumbi, a Stanford University marine biologist and co-author of the study published in Science. "It’s going to be too rare and too expensive." Don’t tell that to your local sushi chef. Over the past three decades, the fish export trade has grown fourfold, to 30 million tons, and its value has increased ninefold, to $71 billion. The dietary attractiveness of seafood has stoked demand. About 90% of the ocean’s big predators—like cod and tuna—have been fished out of existence. Increasingly, fish and shrimp farms are filling the shortfall. Though touted as a solution to overfishing, many of them have—along with rampant coastal development, climate change and pollution—devastated the reefs, mangroves and seagrass beds where many commercially valuable fish hatch. Steven Murawski, chief scientist at the U. S. National Marine Fisheries Service, finds Worm’s headlining prediction far too pessimistic. Industry experts arc even more skeptical. "There’s now a global effort to reduce or eliminate fishing practices that aren’t sustainable," says industry analyst Howard Johnson. "With that increased awareness, these projections just aren’t realistic." Perhaps. Still, the destructive fishing practices that have decimated tuna and cod have not declined worldwide, as Johnson suggests. Up to half the marine life caught by fishers is discarded, often dead, as bycatch, and vibrant coral forests are still being stripped bare by dragnets. Worm argues that fisheries based on ecosystems stripped of their biological diversity are especially prone to collapse. At least 29% of fished species have already collapsed, according to the study, and the trend is accelerating. So what’s a fish eater to do "Vote with your wallet," says Michael Sutton, who runs the Monterey Bay Aquarium’s Seafood Watch program in California. Since 1999, the aquarium has handed out pocket guides listing sustainably harvested seafood. The Marine Stewardship Council has partnered with corporations to similarly certify wild and farm-raised seafood. Some 370 products in more than two dozen countries bear the British group’s "Fish Forever" label of approval. Wal-Mart and Red Lobster, among others, have made commitments to sell sustainably harvested seafood. But that’s just a spit in the ocean unless consumers in Japan, India, China and Europe join the chorus for change. "If everyone in the U. S. started eating sustainable seafood," says Worldwatch Institute senior researcher Brian Halweil, "it would be wonderful, but it wouldn’t address the global issues. We’re at the very beginning of this.\ What is the main idea of the passage
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In this section you will hear everything ONCE ONLY. Listen carefully and then answer the questions that follow. Mark the correct answer to each question on your answer sheet. Questions 1 to 5 are based on an interview. At the end of the interview you will be given 10 seconds to answer each of the following five questions. Now listen to the interview. When it comes to nursing articles, Sam suggests that parents should
Jonas Frisen had his eureka moment in 1997. Back then, scientists suspected that there was a special type of cell in the brain that had the power to give rise to new brain cells. If they could harness these so-called neural stem cells to regenerate damaged brain tissue, they might someday find a cure for such brain diseases as Alzheimer’s and Parkinson’s. But first they had to figure out where neural stem cells were and what they looked like. Frisen, then a freshly minted Ph. D. at the Karolinska Institute in Stockholm, was peering through his microscope at some tissue taken from a rat’s injured spinal cord when he saw cells that appeared to have been enervated by the injury, as though they were busy making repairs. Frisen thought these might be the neural stem cells scientists had been looking for. It took him six years of painstaking research to make sure. Frisen is quick to emphasize that his research is basic and that treatments are years off. But the findings so far hint at extraordinary potential. Two years ago he identified neural stem cells in the adult human brain, And he’s now researching the mechanisms by which these cells grow into different types of brain cells. Rather than growing brain tissue in a petri-dish and implanting it in, say, the forebrain of a Parkinson’s patient, doctors might someday stimulate the spontaneous growth of new neural cells merely by administering a drug. "It sounds like science fiction," Frisen says, "but we can already do it in mice." In 2007 he will publish the results of his recent experiments. He’s isolated a protein in the mouse brain that inhibits the generation of nerve cells. Using other chemicals, he’s been able to block the action of this inhibitor, which in turn leads to the production of new brain cells. Frisen honed his analytical mind at the dinner table in Goteborg, in southwest Sweden. His mother was a mathematics professor and his father was an ophthalmologist. Frisen went to medical school intending to be a brain surgeon or perhaps a psychiatrist, but ended up spending all his free time in the lab. In 1998 he got seed money from a Swedish venture capitalist to set up his own company, NeuroNova, to commercialize his work. A private foundation tried to lure him to Texas, but Swedish businessman Marcus Storch persuaded him to stay by funding a 15-year professorship at Karolinska, covering his salary and the running costs of his 15-person lab. "Jonas Frisen stood out from all candidates by far," says Storch, whose Tobias Foundation sponsors stem-cell research. "He is something of a king in Sweden." Two years ago two more venture capitalists helped the company expand by hiring a CEO and setting up a separate lab. Since most researchers are interested in stem cells taken from embryos, the practice has attracted considerable controversy in the past few years. Frisen has benefited indirectly from research restrictions in the United States, which have driven funds and brain-power to Singapore, the United Kingdom and Sweden. The Bush Administration currently forbids U. S. -funded work on all but 78 approved stem-cell cultures, many of which are located outside the country. In just one sign of the times, the U. S.-based Juvenile Diabetes Research Foundation recently announced grants totaling $20 million for stem-cell research—the largest award yet given to the field by a medical charity—to research institutes in Sweden and elsewhere, but not in the United States. Since Frisen doesn’t work with embryonic stem cells, he’s unwittingly become a champion of the radical right, which argues that scientists ought to concentrate solely on adult stem cells. He happens to disagree. "It would be overoptimistic or outright stupid," he says. "To really understand adult cells, we need to master how embryonic stem cells work." But what really gets Frisen going is when people ask him when they can expect a drug for Parkinson’s and other diseases. "I say, five decades, just to get the number thing out of the way," he quips. "I’m not going to oversell this." When pressed, he admits that clinical trials might begin in five years. That would be a eureka moment worth waiting for. Which of the following statements is TRUE of Frisen
She broke off with a little shudder. It was a relief to Framton Nuttel when the aunt bustled into the room with a whirl of apologies for being late in making her appearance. "I hope Vera has been amusing you" she said. "She has been very interesting," said Framton. "I hope you don’t mind the open window," said Mrs. Sappleton briskly. "My husband and brothers will be home directly from shooting, and they always come in this way. They’ve been out for snipe in the marshes today, so they’ll make a fine mess over my poor carpets. So like you menfolk, isn’t it" She rattled on cheerfully about the shooting and the scarcity of birds, and the prospects for duck in the winter. To Framton it was all purely horrible. He made a desperate but only partially successful effort to turn the talk on to a less ghastly topic; he was conscious that his hostess was giving him only a fragment of her attention, and her eyes were constantly straying past him to the open window and the lawn beyond. It was certainly an unfortunate coincidence that he should have paid his visit on this tragic anniversary. "The doctors agree in ordering me complete rest, an absence of mental excitement, and avoidance of anything in the nature of violent physical exercise," announced Framton, who laboured under the tolerably widespread delusion that total strangers and chance acquaintances are hungry for the least detail of one’s infirmities, their cause and cure. "On the matter of diet they are not so much in agreement," he continued. "No" said Mrs. Sappleton, in a voice which only replaced a yawn at the last moment. Then she suddenly brightened into alert attention-but not to what Framton was saying. "Here they are at last!" she cried. "Just in time for tea, and don’t they look as if they were muddy up to the eyes!" Framton shivered slightly and turned towards the niece with a look intended to convey sympathetic comprehension. The child was staring out through the open window with a dazed horror in her eyes. In a chill shock of nameless fear Framton swung round in his seat and looked in the same direction. In the deepening twilight three figures were walking across the lawn towards the window, they all carried guns under their arms, and one of them was additionally burdened with a white coat hung over his shoulders. A tired brown spaniel kept close at their heels. Noiselessly they neared the house, and then a hoarse young voice chanted out of the dusk: "I said, Bertie, why do you bound" Framton grabbed wildly at his stick and hat; the hall door, the gravel drive, and the from gate were dimly noted stages in his headlong retreat. A cyclist coming along the road had to run into the hedge to avoid imminent collision. "Here we are, my dear," said the bearer of the white mackintosh, coming in through the window, "fairly muddy, but most of it’s dry. Who was that who bolted out as we came up" "A most extraordinary man, a Mr. Nuttel," said Mrs. Sappleton, "could only talk about his illnesses, and dashed off without a word of goodbye or apology when you arrived. One would think he had seen a ghost." "I expect it was the spaniel," said the niece calmly. "He told me he had a horror of dogs. He was once hunted into a cemetery somewhere on the banks of the Ganges by a pack of pariah dogs, and had to spend the night in a newly dug grave with the creatures snarling and grinning and foaming just above him. Enough to make anyone lose their nerve." Romance at short notice was her speciality. The word "infirmities" in the sixth paragraph probably means
Jonas Frisen had his eureka moment in 1997. Back then, scientists suspected that there was a special type of cell in the brain that had the power to give rise to new brain cells. If they could harness these so-called neural stem cells to regenerate damaged brain tissue, they might someday find a cure for such brain diseases as Alzheimer’s and Parkinson’s. But first they had to figure out where neural stem cells were and what they looked like. Frisen, then a freshly minted Ph. D. at the Karolinska Institute in Stockholm, was peering through his microscope at some tissue taken from a rat’s injured spinal cord when he saw cells that appeared to have been enervated by the injury, as though they were busy making repairs. Frisen thought these might be the neural stem cells scientists had been looking for. It took him six years of painstaking research to make sure. Frisen is quick to emphasize that his research is basic and that treatments are years off. But the findings so far hint at extraordinary potential. Two years ago he identified neural stem cells in the adult human brain, And he’s now researching the mechanisms by which these cells grow into different types of brain cells. Rather than growing brain tissue in a petri-dish and implanting it in, say, the forebrain of a Parkinson’s patient, doctors might someday stimulate the spontaneous growth of new neural cells merely by administering a drug. "It sounds like science fiction," Frisen says, "but we can already do it in mice." In 2007 he will publish the results of his recent experiments. He’s isolated a protein in the mouse brain that inhibits the generation of nerve cells. Using other chemicals, he’s been able to block the action of this inhibitor, which in turn leads to the production of new brain cells. Frisen honed his analytical mind at the dinner table in Goteborg, in southwest Sweden. His mother was a mathematics professor and his father was an ophthalmologist. Frisen went to medical school intending to be a brain surgeon or perhaps a psychiatrist, but ended up spending all his free time in the lab. In 1998 he got seed money from a Swedish venture capitalist to set up his own company, NeuroNova, to commercialize his work. A private foundation tried to lure him to Texas, but Swedish businessman Marcus Storch persuaded him to stay by funding a 15-year professorship at Karolinska, covering his salary and the running costs of his 15-person lab. "Jonas Frisen stood out from all candidates by far," says Storch, whose Tobias Foundation sponsors stem-cell research. "He is something of a king in Sweden." Two years ago two more venture capitalists helped the company expand by hiring a CEO and setting up a separate lab. Since most researchers are interested in stem cells taken from embryos, the practice has attracted considerable controversy in the past few years. Frisen has benefited indirectly from research restrictions in the United States, which have driven funds and brain-power to Singapore, the United Kingdom and Sweden. The Bush Administration currently forbids U. S. -funded work on all but 78 approved stem-cell cultures, many of which are located outside the country. In just one sign of the times, the U. S.-based Juvenile Diabetes Research Foundation recently announced grants totaling $20 million for stem-cell research—the largest award yet given to the field by a medical charity—to research institutes in Sweden and elsewhere, but not in the United States. Since Frisen doesn’t work with embryonic stem cells, he’s unwittingly become a champion of the radical right, which argues that scientists ought to concentrate solely on adult stem cells. He happens to disagree. "It would be overoptimistic or outright stupid," he says. "To really understand adult cells, we need to master how embryonic stem cells work." But what really gets Frisen going is when people ask him when they can expect a drug for Parkinson’s and other diseases. "I say, five decades, just to get the number thing out of the way," he quips. "I’m not going to oversell this." When pressed, he admits that clinical trials might begin in five years. That would be a eureka moment worth waiting for. According to the passage, what does the author think of Frisen’s findings
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