插播一则劲爆新闻，16系列封神榜重磅出炉！所有人速度围观、踩楼、看数据！今后封神榜单将自动悬挂一周，以示瞻仰之情~ 咳咳，by 神猴
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Hello！最近一直在忙论文，但是小分队还是要坚持的，加油！第三和第四篇来自一篇文章，标题用白色标记的，读完文章后用鼠标拖动一下就看到了，在图片上面~
[Time 1] Article 1 ( Check the title later)
Fingerprints, Now There's 'Breathprints'
What makes your body different from everyone else's? Maybe you're thinking fingerprints or the DNA that you leave on everything you touch. Now, add your breath to that list. Researchers have found that individuals have unique "breathprints" that change throughout the day and that reflect chemical reactions going on in the body. In the new study, reported today in PLOS ONE, volunteers blew air into a mass spectrometer (pictured), which split the exhalation into its chemical components. Unlike older methods, which required samples to be prepared and then injected into the machine, the device used in this study can directly accept breath and show the results in seconds. The researchers found that individuals' breathprints changed slightly from sample to sample, but always kept a core signature that was unique enough to identify that person. That means that a breathprint reflects what's going on in a person's body and isn't just a random sampling of room air, they conclude. In the future, the authors say that such a technique could reveal the drugs you've been taking or biomarkers of diseases such as cancer. Smaller versions of the machine shown above could make their way into doctors' offices and could be used to detect doping at races without sending samples to a lab. [字数：211] [Time 2] Article 2 NASA Picks Next Exoplanet Mission for Launch in 2017
NASA plans to launch an exoplanet-hunting satellite and an instrument to study neutron stars in 2017. Both are small missions that could have a big impact. The Transiting Exoplanet Survey Satellite (TESS) will aim to find terrestrial planets in the habitable zones of nearby stars. It will use an array of wide-field cameras to survey the brightest stars in the sun's neighborhood in hopes of detecting exoplanets such as gas giants and rocky, Earth-sized planets. Some of these planets, researchers hope, will become candidates for follow-up studies of their atmospheres by the James Webb Space Telescope, scheduled for launch in 2018. The other mission chosen by NASA is the Neutron Star Interior Composition Explorer (NICER), which will be deployed on the International Space Station. The instrument will observe x-rays flashed by neutron stars, helping researchers understand the nature of matter contained in these dense, spinning objects that result from the collapse of massive stars. "TESS will carry out the first space-borne all-sky transit survey, covering 400 times as much sky as any previous mission," said George Ricker, a research scientist at the Massachusetts Institute of Technology in Cambridge and principal investigator of the mission, in a statement. "It will identify thousands of new planets in the solar neighborhood, with a special focus on planets comparable in size to the Earth." Both TESS and NICER have been selected as part of NASA's Explorer program, out of four concept studies submitted to the agency in the fall last year. TESS will get up to $200 million, and NICER—to be led by Keith Gendreau of NASA's Goddard Space Flight Center in Greenbelt, Maryland—will receive up to $55 million. [字数：277] [Time 3] Article 3 Bigger not always better for penis sizeStudy reveals diminishing returns in attractiveness of larger-than-average genitalia.
Researchers report today that penis size does matter to women — though within limits. The finding suggests that women’s preferences could have fuelled the evolution of the human male penis, which is longer and thicker than that of any other primate.Male genitalia evolve quickly. They diversify earlier than other physical traits, with a wide variation in size and shape across the animal kingdom that can reveal a species’ evolutionary pressures. Biologists have puzzled, therefore, over what factors might have caused the human penis to become so large. Now, a study published in the Proceedings of the National Academy of Sciences finds that women consider penis size and height equally when judging men’s attractiveness, but both exhibit diminishing returns with greater size and are less important than a masculine body type1.The findings add to a debate that began in 1966 when sexuality researchers William Masters and Virginia Johnson declared penis size to be unimportant to most females. Subsequent studies of women’s preferences, based on questionnaires or line drawings, have reported conflicting results. For the latest study, researchers developed computer-generated images of males that varied independently in three factors: height, shoulder-to-hip ratio and penis length. A sample of 105 heterosexual Australian women each viewed life-sized projections of 53 of the images and rated their sexual attractiveness. Too big to succeed? The data showed an upside-down-U-shaped curve for each trait. The women considered taller men with a more masculine body type (indicated by a larger shoulder-to-hip-size ratio) and longer penis to be more attractive, but not without limits — there were diminishing returns for extreme size, and men with substantially larger-than average features were not found much more attractive than those with only slightly above-average features. Study leader Brian Mautz, a biologist now at the University of Ottawa in Canada, says that there seems to be a ceiling effect for each trait — a point of theoretical peak attractiveness, beyond which women’s ratings will begin to decline. The team’s model predicts that the most attractive penis would measure 12.8–14.2 centimetres in its flaccid state. Mautz notes that this ideal size is relatively closer to the population average (of 9 centimetres) than are the predicted ideals for the other traits, implying that women prefer more extreme shoulder-to-hip ratio and tallness but less extreme penis size. Other researchers say that the findings are an important first step but fall short of showing a role for sexual selection in the evolution of human penis size, a point that Mautz concedes. “It's hard to extrapolate much from the data,” he says. ”More work needs to be done to connect the dots.” Alan Dixson, a primatologist at Victoria University of Wellington in New Zealand, says that the research should be broadened to include women from other countries and cultures — especially those from indigenous populations in which full clothing is not usually worn. More crucially, female preference needs to be tied to reproductive success, says William Eberhard, an evolutionary biologist at the University of Costa Rica in San Pedro. Women may prefer a large penis when choosing a partner, but that doesn’t necessarily translate into more offspring who carry those genes. Still, the findings have immediate implications for sexual medicine and counselling, says Geoffrey Miller, an evolutionary psychologist at New York University. “This research will allow an uncomfortable subject to become a legitimate topic of discussion.” [字数：342] [Time 5] Article 4 Climate Change Will Boost Plane Turbulence
Get used to a bumpy ride. The strength and frequency of atmospheric turbulence affecting transatlantic flights will increase by midcentury, a new study suggests. Researchers used a global climate model to assess the intensity of clear-air turbulence—the kind that stems from wind shear. In particular, the researchers assessed the intensity of turbulence at a point in the future when carbon dioxide concentrations are twice the levels they were before human industrial activity began boosting them substantially—which, according to a middle-of-the-road emissions scenario, will likely occur sometime in the 2050s. For their analysis, they simulated atmospheric conditions at an altitude of about 12 kilometers (a typical cruise altitude for airliners) in the northern portion of the North Atlantic, a region that includes most transatlantic routes. During winter months, when clear-air turbulence is at its worst in that area, 16 of the 21 often-used ways in which scientists measure turbulence suggest that the average intensity of the plane-rattling phenomenon (image depicts turbulence intensity on a random winter day) will be between 10% and 40% stronger when CO2 concentrations are double their preindustrial value, the researchers report online today in Nature Climate Change. Accordingly, the frequency of moderate-or-greater turbulence—intensities at which passengers will experience accelerations of 0.5 g or more, which are strong enough to toss items about the cabin—will rise by between 40% and 170%. As a result of pilots needing to dodge strong turbulence, flight paths will become longer, and fuel consumption and carbon dioxide emissions will increase—possibly leading to even more turbulence. Hold on tight. [字数：260] [越障] Article 5 The Fuel Of The Future
WHICH source of renewable energy is most important to the European Union? Solar power, perhaps? (Europe has three-quarters of the world’s total installed capacity of solar photovoltaic energy.) Or wind? (Germany trebled its wind-power capacity in the past decade.) The answer is neither. By far the largest so-called renewable fuel used in Europe is wood. In its various forms, from sticks to pellets to sawdust, wood (or to use its fashionable name, biomass) accounts for about half of Europe’s renewable-energy consumption. In some countries, such as Poland and Finland, wood meets more than 80% of renewable-energy demand. Even in Germany, home of the Energiewende (energy transformation) which has poured huge subsidies into wind and solar power, 38% of non-fossil fuel consumption comes from the stuff. After years in which European governments have boasted about their high-tech, low-carbon energy revolution, the main beneficiary seems to be the favoured fuel of pre-industrial societies. The idea that wood is low in carbon sounds bizarre. But the original argument for including it in the EU’s list of renewable-energy supplies was respectable. If wood used in a power station comes from properly managed forests, then the carbon that billows out of the chimney can be offset by the carbon that is captured and stored in newly planted trees. Wood can be carbon-neutral. Whether it actually turns out to be is a different matter. But once the decision had been taken to call it a renewable, its usage soared. In the electricity sector, wood has various advantages. Planting fields of windmills is expensive but power stations can be adapted to burn a mixture of 90% coal and 10% wood (called co-firing) with little new investment. Unlike new solar or wind farms, power stations are already linked to the grid. Moreover, wood energy is not intermittent as is that produced from the sun and the wind: it does not require backup power at night, or on calm days. And because wood can be used in coal-fired power stations that might otherwise have been shut down under new environmental standards, it is extremely popular with power companies.
Money grows on trees The upshot was that an alliance quickly formed to back public subsidies for biomass. It yoked together greens, who thought wood was carbon-neutral; utilities, which saw co-firing as a cheap way of saving their coal plants; and governments, which saw wood as the only way to meet their renewable-energy targets. The EU wants to get 20% of its energy from renewable sources by 2020; it would miss this target by a country mile if it relied on solar and wind alone. The scramble to meet that 2020 target is creating a new sort of energy business. In the past, electricity from wood was a small-scale waste-recycling operation: Scandinavian pulp and paper mills would have a power station nearby which burned branches and sawdust. Later came co-firing, a marginal change. But in 2011 RWE, a large German utility, converted its Tilbury B power station in eastern England to run entirely on wood pellets (a common form of wood for burning industrially). It promptly caught fire. Undeterred, Drax, also in Britain and one of Europe’s largest coal-fired power stations, said it would convert three of its six boilers to burn wood. When up and running in 2016 they will generate 12.5 terawatt hours of electricity a year. This energy will get a subsidy, called a renewable obligation certificate, worth £45 ($68) a megawatt hour (MWh), paid on top of the market price for electricity. At current prices, calculates Roland Vetter, the chief analyst at CF Partners, Europe’s largest carbon-trading firm, Drax could be getting £550m a year in subsidies for biomass after 2016—more than its 2012 pretax profit of £190m. With incentives like these, European firms are scouring the Earth for wood. Europe consumed 13m tonnes of wood pellets in 2012, according to International Wood Markets Group, a Canadian company. On current trends, European demand will rise to 25m-30m a year by 2020. Europe does not produce enough timber to meet that extra demand. So a hefty chunk of it will come from imports. Imports of wood pellets into the EU rose by 50% in 2010 alone and global trade in them (influenced by Chinese as well as EU demand) could rise five- or sixfold from 10m-12m tonnes a year to 60m tonnes by 2020, reckons the European Pellet Council. Much of that will come from a new wood-exporting business that is booming in western Canada and the American south. Gordon Murray, executive director of the Wood Pellet Association of Canada, calls it “an industry invented from nothing”. Prices are going through the roof. Wood is not a commodity and there is no single price. But an index of wood-pellet prices kept by the Argus Biomass Report rose from $116 a tonne in August 2010 to $129 a tonne at the end of 2012. Prices for hardwood from western Canada have risen by about 60% since the end of 2011. This is putting pressure on companies that use wood as an input. About 20 large saw mills making particle board for the construction industry have closed in Europe during the past five years, says Petteri Pihlajamaki of Poyry, a Finnish consultancy (though the EU’s building bust is also to blame). Higher wood prices are hurting pulp and paper companies, which are in bad shape anyway: the production of paper and board in Europe remains almost 10% below its 2007 peak. In Britain, furniture-makers complain that competition from energy producers “will lead to the collapse of the mainstream British furniture-manufacturing base, unless the subsidies are significantly reduced or removed”. But if subsidising biomass energy were an efficient way to cut carbon emissions, perhaps this collateral damage might be written off as an unfortunate consequence of a policy that was beneficial overall. So is it efficient? No. Wood produces carbon twice over: once in the power station, once in the supply chain. The process of making pellets out of wood involves grinding it up, turning it into a dough and putting it under pressure. That, plus the shipping, requires energy and produces carbon: 200kg of CO2 for the amount of wood needed to provide 1MWh of electricity. This decreases the amount of carbon saved by switching to wood, thus increasing the price of the savings. Given the subsidy of £45 per MWh, says Mr Vetter, it costs £225 to save one tonne of CO2 by switching from gas to wood. And that assumes the rest of the process (in the power station) is carbon neutral. It probably isn’t. A fuel and your money Over the past few years, scientists have concluded that the original idea—carbon in managed forests offsets carbon in power stations—was an oversimplification. In reality, carbon neutrality depends on the type of forest used, how fast the trees grow, whether you use woodchips or whole trees and so on. As another bit of the EU, the European Environment Agency, said in 2011, the assumption “that biomass combustion would be inherently carbon neutral…is not correct…as it ignores the fact that using land to produce plants for energy typically means that this land is not producing plants for other purposes, including carbon otherwise sequestered.” Tim Searchinger of Princeton University calculates that if whole trees are used to produce energy, as they sometimes are, they increase carbon emissions compared with coal (the dirtiest fuel) by 79% over 20 years and 49% over 40 years; there is no carbon reduction until 100 years have passed, when the replacement trees have grown up. But as Tom Brookes of the European Climate Foundation points out, “we’re trying to cut carbon now; not in 100 years’ time.” In short, the EU has created a subsidy which costs a packet, probably does not reduce carbon emissions, does not encourage new energy technologies—and is set to grow like a leylandii hedge. 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发表于 2013-4-9 19:41:01
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