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速度1:
  Reprogrammed Cells Earn Nobel Honor The discovery that cellular development is not a one-way street has earned this year's Nobel Prize in physiology or medicine. John B. Gurdon, a developmental biologist at the Wellcome Trust/Cancer Research UK Gurdon Institute at the University of Cambridge in the United Kingdom, and Shinya Yamanaka, a stem cell researcher at Kyoto University in Japan and the Gladstone Institute at the University of California, San Francisco, have won the prize for their discovery that mature cells can be reprogrammed to resemble the versatile cells of a very early embryo. These so-called pluripotent cells have the ability to become any of the body's tissues. The pair's work, which bridges two eras of modern biology, "revolutionised our understanding of how cells and organisms develop," the Nobel committee wrote in its award announcement. The ability to reprogram adult cells has made it possible for researchers to study certain diseases in new waysand raises the possibility of someday growing replacement tissues or even organs in the lab. "I think everyone who works on developmental biology and on the understanding of disease mechanisms will applaud these excellent and clear choices for the Nobel prizes. "Countless labs' work build on the breakthroughs they have pioneered," says John Hardy, a neuroscientist the University College London. In normal development, cells mature from their pluripotent state into various, specialized cell types a neuron, muscle cell, or skin cell, for example. For many years developmental biologists thought that the cellular maturation process was irreversible. In 1962, however, John Gurdon, working at the University of Oxford, showed that under the right conditions, a mature cell nucleus could become developmentally young again. (270)
速度2: He replaced the nucleus of a frog egg with a nucleus taken from a cell in a tadpole's intestine. In a few cases, the egg cell was able to "reprogram" the DNA in the tadpole nucleus and the egg cell developed into an adult frog-the first animals cloned from mature cells*. Other researchers built on Gurdon's findings, most famously the team that cloned Dolly the sheep using a similar feat of nuclear transplantation. That breakthrough demonstrated that mammal cells could undergo the same transformation from mature to immature. More than 4 decades later, Shinya Yamanaka showed that an egg cell wasn't necessary to reprogram a cell's DNA to pluripotency. Working with mouse cells, Yamanaka and his colleagues found that by adding extra copies of four genes to skin cells growing in a laboratory dish, they could prompt the cells to act like embryonic stem (ES) cells, the pluripotent cells taken from early embryos. A few years later, Yamanaka and other teams showed that a similar technique could work on human cells. That has allowed scientists to establish stable, growing populations of cells from patients with diseases such as Amyotrophic Lateral Sclerosis. (191)
速度3: Researchers can study such cells, known as induced pluripotent stem (iPS) cells for disease insights. In the case of ALS, for example, they can prompt them to become muscle and nerve cells that mimic the problems seen in people with the condition. Yamanaka, who originally trained as an orthopedic surgeon, welcomed the Nobel honor with a note of caution about how quickly it might yield medical benefits. "I feel great joy, but at the same time a great responsibility. The iPS technology is new and we actually have not been able to apply these findings to the development of new therapies or drugs. I feel we have to continue research to make a contribution to society as early as possible." Yamanaka's work was also welcomed because it offers researchers a potential alternative to human ES cells, which have been ethically and politically controversial given their source. Scientists are still working to understand exactly how cells reprogrammed by the addition of genes differ from the pluripotent cells that are found in embryos, and how those differences might affect the ways the cells can be used. Gurdon released a statement highlighting how the two scientist's research had moved from basic science into medicine: "I am immensely honoured to be awarded this spectacular recognition, and delighted to be due to receive it with Shinya Yamanaka, whose work has brought the whole field within the realistic expectation of therapeutic benefits. ... It is particularly pleasing to see how purely basic research, originally aimed at testing the genetic identity of different cell types in the body, has turned out to have clear human health prospects." At the press conference at Kyoto University today, Yamanaka said that he couldn't have carried out his work without the financial support he has received from the country." I really feel that Japan is receiving this prize." In 2009, he and Gurdon shared the Albert Lasker Basic Medical Research Award. (320)
速度4:
 At MIT, Romney and Obama Campaigns Debate Energy Policy CAMBRIDGE, MASSACHUSETTS—There might be few better places to debate the future of U.S. energy policy than at the Massachusetts Institute of Technology (MIT), a campus that has nurtured its share of energy innovations. Representatives of the Barack Obama and Mitt Romney presidential campaigns squared off here last night in the school’s cavernous Kresge Hall. The sparks didn’t exactly fly, and undecided voters were probably left unswayed, but the debate did sharpen up some of the differences in how an Obama or Romney administration would steer the world’s second largest consumer of energy, passed only recently by China. Obama’s champion was Joseph Aldy, an economist at nearby Harvard University and a former White House adviser on energy and environment. Romney’s man was Oren Cass, a lawyer and domestic policy director for the Romney campaign. The early part of the debate, moderated by Technology Review editor Jason Pontin, focused on the long-sought American dream of “energy independence.” Both sides cling tightly to that dream. Aldy recalled growing up in the mid-1970s, when his family joined the long lines of cars stranded at the gas pumps during the oil crisis. Cass lamented that the United States has actually grown more dependent on foreign oil since then. They both agreed that domestic natural gas will be crucial for weening the United States to energy independence. Their few differences hit familiar Republican vs. Democrat talking points. Aldy talked up the promise of alternative energy sources such as wind and solar, while Cass argued for more oil drilling on U.S. territory, particularly in the Arctic National Wildlife Refuge (ANWR) in Alaska. (266)
速度5: Disagreement over the future of the Alaskan refuge provided one of the few moments during the debate when an otherwise polite audience packed with scientists turned rowdy. Aldy made the case for protecting the Arctic refuge from drilling because of its ecological uniqueness. Cass dismissed that idea with an argument that made the crowd groan and grumble. “My daughter will probably never visit ANWR,” he said, implying that tourism is the only value of a nature preserve. At about this point, the moderator looked up from his iPhone and addressed the cameras providing live video feed on the Internet. “People on Twitter are asking, ‘Why haven’t they mentioned climate change yet?’ I assure you, we’re getting to that.” Cass was blunt on the topic: A Romney administration, he said, would not put a high priority on reducing U.S. emissions of carbon. He acknowledged that many Americans are passionate about the issue, especially after Obama’s “inspiring” speeches early in his presidency. But since then, Cass pointed out, the Administration has done little to address climate. In his rebuttal, Aldy did not deny the charge, but he placed the blame squarely on “intransigence” in Congress. Every time the president has introduced legislation for mitigating climate change, Aldy said, “the Republicans have blocked it.” Later, the crowd groaned again when Cass deployed an argument frequently used by climate skeptics: The connection between human activity and climate change “needs more scientific study,” he said, echoing a point made in this year’s Republican Party platform. Who won the debate? Team Obama, at least according to Jocelyn Newhouse, a Ph.D. student at MIT working on large-scale battery technologies. “[Aldy] was the only one who directly answered the questions,” she concluded. But Newhouse was happy to hear one thing from the Romney camp. “Both sides said they will continue supporting ARPA-E,” the U.S. Department of Energy’s Advanced Research Projects Agency-Energy, which funds high-risk, early stage technologies. “I’m completely funded by ARPA-E,” she said, “and so are half of our postdocs.” (333)
越障: America’s Real Jobs Gap It’s not often that you read a book that solves a mystery that has baffled you for years. But that's what happened a couple of weeks ago when I read Why Good People Can't Get Jobs: The Skills Gap and What Companies Can Do About It. Written by Peter Cappelli, a professor of management and director of the Wharton School’s Center for Human Resources at the University of Pennsylvania, this tiny book provides a remarkably enlightening, strikingly original, and extremely important explanation of what’s wrong with America’s skilled labor market and how to fix it. Should this little book get the attention it deserves, it could, like Rachel Carson's Silent Spring or Michael Harrington's The Other America , change the way Americans think about a pressing issue. That's because the book resolves the vexing conundrum of how two conflicting narratives about high-skilled employment have coexisted in our national conversation. On the one hand, countless unemployed or underemployed workers with perfectly good skills, education, and experience are struggling through a severe job drought, many sending out hundreds of applications and resumes to no avail. On the other hand, employers (especially in technical fields) complain of great difficulty finding workers, citing serious gaps between the requirements of available jobs and the skills of the workforce. One company that Cappelli mentions didn’t find a single worker that it considered qualified among 25,000 applicants for a fairly ordinary engineering job. Employers and their organizations fault an inadequate school system that fails to prepare Americans and restrictive immigration laws that prevent employers from importing the skilled workers they need from abroad. Is one side hallucinating? Are American workers really not up to the challenge of today’s workplace? Are employers, as some critics argue, lying to hold down wages? Is something else entirely going on? Something is indeed broken, Cappelli compellingly argues, but it’s not America’s schools or the skills of its workers. He finds the workforce “largely competent and able” and clearly up to the jobs on offer. Instead, Cappelli writes, “the hiring process by which supply and demand are brought together is an absolute mess.” The needed workers are available, but employers don’t know it because they use ineffective, self-defeating methods to evaluate applicants’ qualifications. They also eschew obvious and time-tested steps that could mold those abilities to meet their exact needs. Fixing “the present, debilitating disconnect between job supply and job demand” would immeasurably aid countless companies and workers, saving the former the huge but generally unrecognized costs of persistent vacancies and the latter the very obvious costs of unemployment (and underemployment). Fixing this problem—which isn't that hard—could unleash a new age of invention and prosperity in the United States. The main reason that companies aren’t finding the workers they seek in an ocean of available ability, Cappelli believes, is that in recent decades, for reasons he explains, those companies have allowed their traditional human resources (HR) departments and training programs to atrophy. Another reason is that some complaining companies simply offer too little money to attract the people they want. The current lack of adequately staffed HR departments, and companies’ refusal to teach workers on the job, have combined to produce what the book terms “a Home Depot view of the hiring process, in which filling a job vacancy is seen as akin to replacing a part in a washing machine. … Like a replacement part, job requirements have very precise specifications. Job candidates must fit them perfectly or the job won’t be filled.” The problem, Cappelli writes, is that “no perfect fit exists between applicants and job requirements.” In a great many cases, people with various combinations of credentials and experience can do a given job well, and work can be structured in many different ways. In decades past, companies routinely hired people with capabilities related to the work and then, if necessary, trained them to do specific jobs; those jobs needed doing, after all, and there didn't seem to be any viable staffing alternatives. But then Silicon Valley “invented the ‘free agent’ model of hiring for new skills rather than training and then letting workers go once those skills aren’t needed.” That model has spread to other industries. Rather than investing in workers to cultivate the skills that companies need, many employers now think—erroneously, Cappelli persuasively argues—that it is cheaper to limit hiring to people who can do a job from day one. The best way to ensure that applicants have the desired skills, those companies believe, is to find people who’ve done the job before. We have often mentioned in this space that many nonacademic employers complain that early-career scientists don't understand business culture and such practices as budgeting and project management. Following Cappelli’s logic, companies could solve that problem by hiring deeply educated, very able people and then providing on-the-job opportunities—as part of a probationary period, perhaps—to pick up the nonscientific knowledge they lack. Instead, too many employers refuse to consider applicants who do not already meet exact requirements. Jobs stay needlessly unfilled. Workers stay unemployed. |
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