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肾盂肾炎最常见的致病菌是
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治疗肺结核气阴耗伤证，应首选（）
The "grid" would be like （）, who can perform your tasks efficiently.
Debate over the Use of Renewable EnergyAusubel of Rockefeller University in New York, US says the key renewable (可再生的) energy sources, including sun, wind and biofuels, would all require vast amounts of land if developed up to large scale production - unlike nuclear power. That land would be far better (51) alone, he says. Renewables look (52) when they are quite small. But if we start producing renewable energy on a large (53) , the fallout (结果) is going to be horrible.Ausubel draws his conclusions by analysing the amount of energy that renewables, natural gas and nuclei (原子核) can (54) in terms of power per square metre of land used. Moreover, he claims that (55) renewable energy use increases, this measure of efficiency will decrease as the best land for wind, biofuels, and solar power gets used up.Solar power is much more (56) than biofuel in terms of the area of land used, but it would still (57) 150 square kilometres of photovoltaic (光电的) cells to match the energy production of the 1000 MW nuclear plant. In another example, he says (58) the 2005 US electricity demand via wind power alone would need 780,000 square kilometres, an area the (59) of Texas.However, several experts are highly critical of Ausubel’s (60) . John Turner of the US government’s National Renewable Energy Laboratory says that even if the US got all of its (61) from solar energy, it would still need less than half the amount of land that has been paved over (62) highways. Further, it need not (63) up additional land. The US could get a quarter of its energy just from covering rooftops of existing buildings, he says.According to Turner, the same "dual use" also (64) to wind power. "The footprint for wind is only 5% of the land that it (65) . Farmers can still farm the land that the turbines are on." Turner says looking solely at land use is an oversimplification of the issue. 63（）
第三篇Why Humans Walk on Two LegsA team of scientists that studied chimpanzees (黑猩猩) trained to use treadmills(跑步机) has gathered new evidence suggesting that our earliest apelike ancestors started walking on two legs because it required less energy than getting around on all fours.Michael Sockol, researcher of UC Davis, worked for two years to find an animal trainer willing to coax (劝诱) adult chimps to walk on two legs and to walk on ail fours.The five chimps also wore face masks used to help the researchers measure oxygen consumption. While the chimps worked out, the scientists collected data that allowed them to calculate which method of locomotion (移动) used less energy and why. The team gathered the same information for four adult humans walking on a treadmill.The researchers found that human walking used about 75 percent less energy and burned 75 percent fewer calories than quadrupedal and bipedal walking in chimpanzees. They also found that for some but not all of the chimps, walking on two legs was no more costly than on all fours."We were prepared to find that all of the chimps used more energy walking on two legs -but that finding wouldn’t have been as interesting," Sockol said. "What we found was much more telling. For three chimps, bipedalism was more expensive, but for the other two chimps, this wasn’t the case. One spent about the same energy walking on two legs as on all fours. The other used less energy walking upright." These two chimps had different gaits (步法) and anatomy (解剖) than their quadrupedal peers.Taken together, the findings provide support for the hypothesis that anatomical (解剖学的) differences affecting gait existed among our earliest apelike ancestors, and that these differences provided the geneticvariation which natural selection could act on when changes in the environment gave bipeds an advantage over quadrupeds.Fossil and molecular evidence suggests the earliest ancestors of the human family lived in forested areas in equatorial Africa in the late Miocene era (中世纪) some 8 to 10 million years ago, when changes in climate may have increased the distance between food patches. That would have forced our earliest ancestors to travel longer distances on the ground and favored those who could cover more ground using less energy."This isn’t the complete answer," Sockol said. "But it’s a good piece of a puzzle humans have always wondered about: How and why did we become human And why do we alone walk on two legs" The word "quadrupeds" in paragraph 6 is a technical word for（）
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