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阅读理解 If you are reading this article, antibiotics have probably saved your life—and not once but several times. A rotten tooth, a knee operation, a brush with pneumonia; any number of minor infections that never turned nasty. You may not remember taking the pills, so unremarkable have these one-time wonder drugs become. Modern medicine relies on antibiotics—not just to cure diseases, but to augment the success of surgery, childbirth and cancer treatments. Yet now health authorities are warning, in uncharacteristically apocalyptic terms, that the era of antibiotics is about to end. In some ways, bacteria are continually evolving to resist the drugs. But in the past we've always developed new ones that killed them again. Not this time. Infections that once succumbed to everyday antibiotics now require last-resort drugs with unpleasant side effects. Others have become so difficult to treat that they kill some 25,000 Europeans yearly. And some bacteria now resist every known antibiotic. Regular readers will know why: New Scientist has reported warnings about this for years. We have misused antibiotics appallingly, handing them out to humans like medicinal candy and feeding them to livestock by the tonne, mostly not for health reasons but to make meat cheaper. Now antibiotic-resistant bacteria can be found all over the world—not just in medical facilities, but everywhere from muddy puddles in India to the snows of Antarctica(南极洲). How did we reach this point without viable successors to today's increasingly ineffectual drugs? The answer lies not in evolution but economics. Over the past 20 years, nearly every major pharmaceutical company has abandoned antibiotics. Companies must make money, and there isn't much in short-term drugs that should be used sparingly. So researchers have discovered promising candidates, but can't reach into the deep pockets needed to develop them. This can be fixed. As we report this week, regulatory agencies, worried medical bodies and Big Phar-ma are finally hatching ways to remedy this market failure. Delinking profits from the volume of drug sold (by adjusting patent rights, say, or offering prizes for innovation) has worked for other drugs, and should work for antibiotics—although there may be a worryingly long wait before they reach the market. One day, though, these will fall to resistance too. Ultimately, we need, evolution-proof cures for bacterial infection: treatments that stop bacteria from causing disease, but don't otherwise inconvenience the little blighters. When resisting drugs confers no selective advantage, drugs will stop breeding resistance. Researchers have a couple of candidates for such treatment. But they fear regulators will drag their feet over such radical approaches. That, too, can be fixed. We must not neglect development of the sustainable medicine we need, the way we have neglected simple antibiotic R D. If we do, one day another top doctor will be telling us that the drugs no longer work—and there really will be no help on the way.

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阅读理解 The biggest thing in operating rooms these days is a million-dollar, multi-armed robot named da Vinci, used in nearly 400,000 surgeries nationwide last year—triple the number just four years earlier. But now the high-tech helper is under scrutiny over reports of problems, including several deaths that may be linked with it and the high cost of using the robotic system. There also have been a few disturbing, freak incidents: a robotic hand that wouldn't let go of tissue grasped during surgery and a robotic arm hitting a patient in the face as she lay on the operating table. Is it time to curb the robot enthusiasm? Some doctors say yes, concerned that the 'wow' factor and heavy marketing have boosted use. They argue that there is not enough robust research showing that robotic surgery is at least as good or better than conventional surgeries. Many U. S. hospitals promote robotic surgery in patient brochures, online and even on highway billboards. Their aim is partly to attract business that helps pay for the costly robot. The da Vinci is used for operations that include removing prostates, gallbladders and wombs, repairing heart valves, shrinking stomachs and transplanting organs. Its use has increased worldwide, but the system is most popular in the United States. For surgeons, who control the robot while sitting at a computer screen rather than standing over the patient, these operations can be less tiring. Plus robot hands don't shake. Advocates say patients sometimes have less bleeding and often are sent home sooner than with conventional laparoscopic surgeries and operations involving large incisions. But the Food and Drug Administration is looking into a spike in reported problems during robotic surgeries. Earlier this year, the FDA began a survey of surgeons using the robotic system. The agency conducts such surveys of devices routinely, but FDA spokeswoman Synim Rivers said the reason for it now 'is the increase in number of reports received' about da Vinci. Reports filed since early last year include at least five deaths. Whether there truly are more problems recently is uncertain. Rivers said she couldn't quantify the increase and that it may simply reflect more awareness among doctors and hospitals about the need to report problems. Doctors aren't required to report such things; device makers and hospitals are. Company spokesman Geoff Curtis said intuitive Surgical has physician-educators and other trainers who teach surgeons how to use the robot. But they don't train them how to do specific procedures robotically, he said, and that it's up to hospitals and surgeons to decide 'if and when a surgeon is ready to perform robotic cases.' A 2010 New England Journal of Medicine essay by a doctor and a health policy analyst said surgeons must do at least 150 procedures to become adept at using the robotic system. But there is no expert consensus on how much training is needed. New Jersey banker Alexis Grattan did a lot of online research before her gallbladder was removed last month at Hackensack University Medical Center. She said the surgeon's many years of experience with robotic operations was an important factor. She also had heard that the surgeon was among the first to do the robotic operation with just one small incision in the belly button, instead of four cuts in conventional keyhole surgery.

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阅读理解 This issue of Science contains announcements for more than 100 different Gorgon Research Conferences, on topics that range from atomic physics to developmental biology. The brainchild(某人的主意) of Nell Gordon of Johns Hopkins University, these week-long meetings are designed to promote intimate, informal discussions of frontier science. Often confined to fewer than 125 attendees, they have traditionally been held in remote places with minimal distractions. Beginning in the early 1960s, I attended the summer Nucleic Acids Gordon Conference in rural New Hampshire, sharing austere (简朴的) dorm facilities in a private boy's school with randomly assigned roommates. As a beginning scientist, I found the question period after each talk especially fascinating, providing valuable insights into the personalities and ways of thinking of many senior scientists whom I had not encountered previously. Back then, there were no cell-phones and no Internet, and all of the speakers seemed to stay for the entire week. During the long, session-free afternoons, graduate students mingled freely with professors. Many lifelong friendships were begun, and—as Gordon intended—new scientific collaborations began. Leap forward to today, and every scientist can gain immediate access to a vast store of scientific thought and to millions of other scientists via the Internet. Why, nevertheless, de in-person scientific meetings remain so valuable for a life in science? Part of the answer is that science works best when there is a deep mutual trust and understanding between the collaborators, which is hard to develop from a distance. But most important is the critical role that face-to-face scientific meetings play in stimulating a random collision of ideas and approaches. The best science occurs when someone combines the knowledge gained by other scientists in non-obvious ways to create a new understanding of how the world works. A successful scientist needs to deeply believe, whatever the problem being tackled, that there is always a better way to approach that problem than the path currently being taken. The scientist is then constantly on the alert for new paths to take in his or her work, which is essential for making breakthroughs. Thus, as much as possible, scientific meetings should be designed to expose the attendees to ways of thinking and techniques that are different from the ones that they already know.

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阅读理解 Back in 1896, the Swedish scientist Svante Arrhenius realized that by burning coal we were adding carbon dioxide to the air, and that this would warm the Earth. But he mentioned the issue only in passing (顺便地), for his calculations suggested it would not become a problem for thousands of years. Others thought that the oceans would soak up any extra CO2, so there was nothing much to worry about. That this latter argument has persisted to this day in some quarters highlights our species' propensity (倾向) to underestimate the scale of our impact on the planet. Even the Earth's vast oceans cannot suck up CO2 as quickly as we can produce it, and we now know the stored CO2 is acidifying the oceans, a problem in itself. Now a handful of researchers are warning that energy sources we normally think of as innocuous could affect the planet's climate too. If we start to extract immense amounts of power from the wind, for instance, it will have an impact on how warmth and water move around the planet, and thus on temperatures and rainfall. Just to be clear, no one is suggesting we should stop building wind farms on the basis of this risk. Aside from the huge uncertainties about the climatic effects of extracting power from the wind, our present and near-term usage is far too tiny to make any difference. For the moment, any negative consequences on the climate are massively outweighed by the effects of pumping out even more CO2. That poses by far the greater environmental threat; weaning ourselves off fossil fuels should remain the priority. Even so, now it is the time to start thinking about the long-term effects of the alternative energy sources we are turning to. Those who have already started to look at these issues report weary, indifferent or even hostile reactions to their work. That's understandable, but disappointing. These effects may be inconsequential, in which case all that will have been wasted is some research time that may well yield interesting insights anyway. Or they may turn out to be sharply negative, in which case the more notice we have, the better. It would be unfortunate to put it mildly, to spend countless trillions replacing fossil-fuel energy infrastructure(基础建设) only to discover that its successor(替代物) is also more damaging than it need be. These climatic effects may even be beneficial. The first, tentative models suggest that extracting large amounts of energy from high-altitude jet streams would cool the planet, counteracting the effects of rising greenhouse gases. It might even be possible to build an energy infrastructure that gives us a degree of control over the weather: turning off wind turbines here, capturing more of the sun's energy there. We may also need to rethink our long-term research priorities. The sun is ultimately the only source of energy that doesn't end up altering the planet's energy balance. So the best bet might be invest heavily in improving solar technology and energy storage—rather than in efforts to harness, say, nuclear fusion. For the moment, all of this remains supposition(推测). But our species has a tendency to myopia. We have nothing to lose, and everything to gain by taking the long view for a change.

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