雅思阅读高分技能之积累词组更有效.doc

雅思阅读高分技能之积累词组更有效 影响雅思阅读重要的因素之一就是词组，雅思很大一部分内容都会考到词组上面,今天给大家带来了雅思阅读高分技-积累词组更有效，希望能帮助到大家，下面就和大家分享，来欣赏一下吧。雅思阅读高分技-积累词组更有效雅思阅读里的词组如何准备?有同学说买本雅思词组书去背，其实不然。比如，stand up，站起来，stood up呢?You stood me up yesterday，不是你昨天站我身上了，叫做你昨天放我鸽子，它跟站、起立完全不一样，这就是说为什么不让大家去背雅思词组书，因为背完了也不知道怎么去用它，词组相当于成语，靠的是积累，这也是阅读的一个重中之重。再如，常见词put放，除了放在雅思之中，put是可以当解释、说明来用。词组put down表放下。另一意思是可以使你失望沮丧，但在警匪片中，put down根据语境就可以是镇压、打倒，或者说制服、拿下。沿用警匪片语境，take down就是要他小命。之所以不翻译成杀死他，处决他，是因为对于词组来说，语境很重要，我们要看的是它的*，不是光背一个词组，这也是咱们口语当中要重点注意的。雅思阅读所有的*都是学术性的*，写作是学术性的写作，包括同学们出国以后的论文，也同样是学术性的。所以，记忆词组最简单的办法就是从雅思阅读中积累，雅思阅读中出现的任何一个词组和短语，都可以运用到你们的写作当中。所以并不是说一篇雅思阅读*13道题做完就结束了，如果你要不仔细把这篇*玩懂，看到里头那些好玩的点，那些好用的词组，那根本不叫学习，只是做了一遍阅读题而已。雅思考试阅读模拟试题及答案解析Doomed drug highlights complications of meddling with cholesterol.1.The failure of a high-profile cholesterol drug has thrown a spotlight on the complicated machinery that regulates cholesterol levels. But many researchers remain confident that drugs to boost levels of good cholesterol are still one of the most promising means to combat spiralling heart disease.2.Drug company Pfizer announced on 2 December that it was cancelling all clinical trials of torcetrapib, a drug designed to raise heart-protective high-density lipoproteins (HDLs). In a trial of 15000 patients, a safety board found that more people died or suffered cardiovascular problems after taking the drug plus a cholesterol-lowering statin than those in a control group who took the statin alone.3.The news came as a kick in the teeth to many cardiologists because earlier tests in animals and people suggested it would lower rates of cardiovascular disease. "There have been no red flags to my knowledge," says John Chapman, a specialist in lipoproteins and atherosclerosis at the National Institute for Health and Medical Research (INSERM) in Paris who has also studied torcetrapib. "This cancellation came as a complete shock."4.Torcetrapib is one of the most advanced of a new breed of drugs designed to raise levels of HDLs, which ferry cholesterol out of artery-clogging plaques to the liver for removal from the body. Specifically, torcetrapib blocks a protein called cholesterol ester transfer protein (CETP), which normally transfers the cholesterol from high-density lipoproteins to low density, plaque-promoting ones. Statins, in contrast, mainly work by lowering the bad low-density lipoproteins.Under pressure5.Researchers are now trying to work out why and how the drug backfired, something that will not become clear until the clinical details are released by Pfizer. One hint lies in evidence from earlier trials that it slightly raises blood pressure in some patients. It was thought that this mild problem would be offset by the heart benefits of the drug. But it is possible that it actually proved fatal in some patients who already suffered high blood pressure. If blood pressure is the explanation, it would actually be good news for drug developers because it suggests that the problems are specific to this compound. Other prototype drugs that are being developed to block CETP work in a slightly different way and might not suffer the same downfall.6.But it is also possible that the whole idea of blocking CETP is flawed, says Moti Kashyap, who directs atherosclerosis research at the VA Medical Center in Long Beach, California. When HDLs excrete cholesterol in the liver, they actually rely on LDLs for part of this process. So inhibiting CETP, which prevents the transfer of cholesterol from HDL to LDL, might actually cause an abnormal and irreversible accumulation of cholesterol in the body. "Youre blocking a physiologic mechanism to eliminate cholesterol and effectively constipating the pathway," says Kashyap.Going up7.Most researchers remain confident that elevating high density lipoproteins levels by one means or another is one of the best routes for helping heart disease patients. But HDLs are complex and not entirely understood. One approved drug, called niacin, is known to both raise HDL and reduce cardiovascular risk but also causes an unpleasant sensation of heat and tingling. Researchers are exploring whether they can bypass this side effect and whether niacin can lower disease risk more than statins alone. Scientists are also working on several other means to bump up high-density lipoproteins by, for example, introducing synthetic HDLs. "The only thing we know is dead in the water is torcetrapib, not the whole idea of raising HDL," says Michael Miller, director of preventive cardiology at the University of Maryland Medical Center, Baltimore.雅思考试阅读模拟试题及答案解析Rogue theory of smell gets a boost1.A controversial theory of how we smell, which claims that our fine sense of odour depends on quantum mechanics, has been given the thumbs up by a team of physicists.2.Calculations by researchers at University College London (UCL) show that the idea that we smell odour molecules by sensing their molecular vibrations makes sense in terms of the physics involved.3.Thats still some way from proving that the theory, proposed in the mid-1990s by biophysicist Luca Turin, is correct. But it should make other scientists take the idea more seriously.4."This is a big step forward," says Turin, who has now set up his own perfume company Flexitral in Virginia. He says that since he published his theory, "it has been ignored rather than criticized."5.Most scientists have assumed that our sense of smell depends on receptors in the nose detecting the shape of incoming molecules, which triggers a signal to the brain. This molecular lock and key process is thought to lie behind a wide range of the bodys detection systems: it is how some parts of the immune system recognise invaders, for example, and how the tongue recognizes some tastes.6.But Turin argued that smell doesnt seem to fit this picture very well. Molecules that look almost identical can smell very different such as alcohols, which smell like spirits, and thiols, which smell like rotten eggs. And molecules with very different structures can smell similar. Most strikingly, some molecules can smell different to animals, if not necessarily to humans simply because they contain different isotopes (atoms that are chemically identical but have a different mass).7.Turins explanation for these smelly facts invokes the idea that the smell signal in olfactory receptor proteins is triggered not by an odour molecules shape, but by its vibrations, which can enourage an electron to jump between two parts of the receptor in a quantum-mechanical process called tunnelling. This electron movement could initiate the smell signal being sent to the brain.8.This would explain why isotopes can smell different: their vibration frequencies are changed if the atoms are heavier. Turins mechanism, says Marshall Stoneham of the UCL team, is more like swipe-card identification than a key fitting a lock.9.Vibration-assisted electron tunnelling can undoubtedly occur it is used in an experimental technique for measuring molecular vibrations. "The question is whether this is possible in the nose," says Stonehams colleague, Andrew Horsfield.10.Stoneham says that when he first heard about Turins idea, while Turin was himself based at UCL, "I didnt believe it". But, he adds, "because it was an interesting idea, I thought I should prove it couldnt work. I did some simple calculations, and only then began to feel Luca could be right." Now Stoneham and his co-workers have done the job more thoroughly, in a paper soon to be published in Physical Review Letters.11.The UCL team calculated the rates of electron hopping in a nose receptor that has an odorant molecule bound to it. This rate depends on various properties of the biomolecular system that are not known, but the researchers could estimate these parameters based on typical values for molecules of this sort.12.The key issue is whether the hopping rate with the odorant in place is significantly greater than that without it. The calculations show that it is which means that odour identification in this way seems theoretically possible.13.But Horsfield stresses that thats different from a proof of Turins idea. "So far things look plausible, but we need proper experimental verification. Were beginning to think about what experiments could be performed."14.Meanwhile, Turin is pressing ahead with his hypothesis. "At Flexitral we have been designing odorants exclusively on the basis of their computed vibrations," he says. "Our success rate at odorant discovery is two orders of magnitude better than the competition." At the very least, he is putting his money where his nose is.