Dadwenttobuysome__________as__________formycousin.
A、stationery;souvenirC
暫無解析
Roguetheoryofsmellgetsaboost
1.Acontroversialtheoryofhowwesmell,whichclaimsthatourfinesenseofodourdependsonquantummechanics,hasbeengiventhethumbsupbyateamofphysicists.
2.CalculationsbyresearchersatUniversityCollegeLondon(UCL)showthattheideathatwesmellodourmoleculesbysensingtheirmolecularvibrationsmakessenseintermsofthephysicsinvolved.
3.That'sstillsomewayfromprovingthatthetheory,proposedinthemid-1990sbybiophysicistLucaTurin,iscorrect.Butitshouldmakeotherscientiststaketheideamoreseriously.
4."Thisisabigstepforward,"saysTurin,whohasnowsetuphisownperfumecompanyFlexitralinVirginia.Hesaysthatsincehepublishedhistheory,"ithasbeenignoredratherthancriticized."
5.Mostscientistshaveassumedthatoursenseofsmelldependsonreceptorsinthenosedetectingtheshapeofincomingmolecules,whichtriggersasignaltothebrain.Thismolecular'lockandkey'processisthoughttoliebehindawiderangeofthebody'sdetectionsystems:itishowsomepartsoftheimmunesystemrecogniseinvaders,forexample,andhowthetonguerecognizessometastes.
6.ButTurinarguedthatsmelldoesn'tseemtofitthispictureverywell.Moleculesthatlookalmostidenticalcansmellverydifferent—suchasalcohols,whichsmelllikespirits,andthiols,whichsmelllikerotteneggs.Andmoleculeswithverydifferentstructurescansmellsimilar.Moststrikingly,somemoleculescansmelldifferent—toanimals,ifnotnecessarilytohumans—simplybecausetheycontaindifferentisotopes(atomsthatarechemicallyidenticalbuthaveadifferentmass).
7.Turin'sexplanationforthesesmellyfactsinvokestheideathatthesmellsignalinolfactoryreceptorproteinsistriggerednotbyanodourmolecule'sshape,butbyitsvibrations,whichcanenourageanelectrontojumpbetweentwopartsofthereceptorinaquantum-mechanicalprocesscalledtunnelling.Thiselectronmovementcouldinitiatethesmellsignalbeingsenttothebrain.
8.Thiswouldexplainwhyisotopescansmelldifferent:theirvibrationfrequenciesarechangediftheatomsareheavier.Turin'smechanism,saysMarshallStonehamoftheUCLteam,ismorelikeswipe-cardidentificationthanakeyfittingalock.
9.Vibration-assistedelectrontunnellingcanundoubtedlyoccur—itisusedinanexperimentaltechniqueformeasuringmolecularvibrations."Thequestioniswhetherthisispossibleinthenose,"saysStoneham'scolleague,AndrewHorsfield.
10.StonehamsaysthatwhenhefirstheardaboutTurin'sidea,whileTurinwashimselfbasedatUCL,"Ididn'tbelieveit".But,headds,"becauseitwasaninterestingidea,IthoughtIshouldproveitcouldn'twork.Ididsomesimplecalculations,andonlythenbegantofeelLucacouldberight."NowStonehamandhisco-workershavedonethejobmorethoroughly,inapapersoontobepublishedinPhysicalReviewLetters.
11.TheUCLteamcalculatedtheratesofelectronhoppinginanosereceptorthathasanodorantmoleculeboundtoit.Thisratedependsonvariouspropertiesofthebiomolecularsystemthatarenotknown,buttheresearcherscouldestimatetheseparametersbasedontypicalvaluesformoleculesofthissort.
12.Thekeyissueiswhetherthehoppingratewiththeodorantinplaceissignificantlygreaterthanthatwithoutit.Thecalculationsshowthatitis—whichmeansthatodouridentificationinthiswayseemstheoreticallypossible.
13.ButHorsfieldstressesthatthat'sdifferentfromaproofofTurin'sidea."Sofarthingslookplausible,butweneedproperexperimentalverification.We'rebeginningtothinkaboutwhatexperimentscouldbeperformed."
14.Meanwhile,Turinispressingaheadwithhishypothesis."AtFlexitralwehavebeendesigningodorantsexclusivelyonthebasisoftheircomputedvibrations,"hesays."Oursuccessrateatodorantdiscoveryistwoordersofmagnitudebetterthanthecompetition."Attheveryleast,heisputtinghismoneywherehisnoseis.
Questions5-9
Completethesentencesbelowwithwordsfromthepassage.UseNOMORETHANTHREEWORDSforeachanswer.
5.Thehypothesisthatwesmellbysensingthemolecularvibrationwasmadeby______.
6.Turin'scompanyisbasedin______.
7.Mostscientistsbelievedthatournoseworksinthesamewayasour______.
8.Differentisotopescansmelldifferentwhen______weighdifferently.
9.AccordingtoAudrewHorsfield,itisstilltobeprovedthat______couldreallyoccurinhumannose.
-----Whataboutthepenyouboughtyesterday?
-----It____________well.Ilikeitverymuch.
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 pressure
5.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."You're blocking a physiologic mechanism to eliminate cholesterol and effectively constipating the pathway," says Kashyap.Going up
7.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.
Questions 7-13
Match torcetrapib，HDLs，statin and CETP with their functions (Questions 8-13)..Write the correct letter A，B，C or D in boxes 8-13 on your answer sheet.NB You may use any letter more than once.
7.It has been administered to over 10,000 subjects in a clinical trial.
8.It could help rid human body of cholesterol.
9.Researchers are yet to find more about it.
10.It was used to reduce the level of cholesterol.
11.According to Kashyap，it might lead to unwanted result if it's blocked.
12.It produced contradictory results in different trials.
13.It could inhibit LDLs.List of choices
A.TorcetrapicB.HDLSC.StatinD.CETP
Selling Digital Music without Copy-protection Makes Sense
A. It was uncharacteristically low-key for the industry’s greatest showman. But the essay published this week by Steve Jobs, the boss of Apple, on his firm’s website under the unassuming title “Thoughts on Music” has nonetheless provoked a vigorous debate about the future of digital music, which Apple dominates with its iPod music-player and iTunes music-store. At issue is “digital rights management” (DRM)—the technology guarding downloaded music against theft. Since there is no common standard for DRM, it also has the side-effect that songs purchased for one type of music-player may not work on another. Apple’s DRM system, called FairPlay, is the most widespread. So it came as a surprise when Mr. Jobs called for DRM for digital music to be abolished.
B. This is a change of tack for Apple. It has come under fire from European regulators who claim that its refusal to license FairPlay to other firms has “l(fā)ocked in” customers. Since music from the iTunes store cannot be played on non-iPod music-players (at least not without a lot of fiddling), any iTunes buyer will be deterred from switching to a device made by a rival firm, such as Sony or Microsoft. When French lawmakers drafted a bill last year compelling Apple to open up FairPlay to rivals, the company warned of “state-sponsored piracy”. Only DRM, it implied, could keep the pirates at bay.
C. This week Mr. Jobs gave another explanation for his former defence of DRM: the record companies made him do it. They would make their music available to the iTunes store only if Apple agreed to protect it using DRM. They can still withdraw their catalogues if the DRM system is compromised. Apple cannot license FairPlay to others, says Mr Jobs, because it would depend on them to produce security fixes promptly. All DRM does is restrict consumer choice and provide a barrier to entry, says Mr Jobs; without it there would be far more stores and players, and far more innovation. So, he suggests, why not do away with DRM and sell music unprotected? “This is clearly the best alternative for consumers,” he declares, “and Apple would embrace it in a heartbeat.”
D. Why the sudden change of heart? Mr Jobs seems chiefly concerned with getting Europe’s regulators off his back. Rather than complaining to Apple about its use of DRM, he suggests, “those unhappy with the current situation should redirect their energies towards persuading the music companies to sell their music DRM-free.” Two and a half of the four big record companies, he helpfully points out, are European-owned. Mr Jobs also hopes to paint himself as a consumer champion. Apple resents accusations that it has become the Microsoft of digital music.
E. Apple can afford to embrace open competition in music players and online stores. Consumers would gravitate to the best player and the best store, and at the moment that still means Apple’s. Mr Jobs is evidently unfazed by rivals to the iPod. Since only 3% of the music in a typical iTunes library is protected, most of it can already be used on other players today, he notes. (And even the protected tracks can be burned onto a CD and then re-ripped.) So Apple’s dominance evidently depends far more on branding and ease of use than DRM-related “l(fā)ock in”.
F. The music giants are trying DRM-free downloads. Lots of smaller labels already sell music that way. Having seen which way the wind is blowing, Mr Jobs now wants to be seen not as DRM’s defender, but as a consumer champion who helped in its downfall. Wouldn’t it lead to a surge in piracy? No, because most music is still sold unprotected on CDs, people wishing to steal music already can do so. Indeed, scrapping DRM would probably increase online-music sales by reducing confusion and incompatibility. With the leading online store, Apple would benefit most. Mr Jobs’s argument, in short, is transparently self-serving. It also happens to be right.
Notes to Reading Passage 1
1. low-key:
抑制的，受約束的，屈服的
2. showman:
開展覽會的人, 出風(fēng)頭的人物
3. unassuming:
謙遜的, 不夸耀的, 不裝腔作勢的
4. iPod：
(蘋果公司出產(chǎn)的)音樂播放器
5. iTunes store：
(蘋果公司出產(chǎn)的)在線音樂商店
6. get off person’s back:
不再找某人的麻煩，擺脫某人的糾纏
7. gravitate:
受吸引，傾向于
8. unfazed:
不再擔(dān)憂，不被打擾
Questions 1-7
Do the following statemets reflect the claims of the writer in Reading Passage 1?
Write your answer in Boxes 1-7 on your answer sheet.
TRUE if the statement reflets the claims of the writer
FALSE if the statement contradicts the claims of the writer
NOT GIVEN if it is impossbile to say what the writer thinks about this
1. Apple enjoys a controlling position in digital music market with its iPod music-player and iTunes music-store.
2. DRM is a government decree issued with a purpose to protect downloaded music from theft by consumers.
3. Lack of standardization in DRM makes songs bought for one kind of music player may not function on another.
4. Apple has been criticized by European regulators since it has refused to grant a license FairPlay to other firms.
5. All music can be easily played on non-iPod music devices from Sony or Microsoft without too much fiddling.
6. Apple depends far more on DRM rather than branding for its dominance of the digital music devices.
7. If DRM was cancelled, Sony would certainly dominate the international digital music market.
Questions 8-10
Choose the appropriate letters A-D and write them in boxes 8-10 on your answe sheet.
8. Which of the following statements about Mr. Jobs’ idea of DRM is NOT TRUE?
A. DRM places restrictions on consumer’ choice of digital music products available.
B. DRM comples iTunes buyers to switch to a device made by Sony or Microsoft.
C. DRM constitutes a barrier for potential consumers to enter digital music markets.
D. DRM hinders development of more stores and players and technical innovation.
9. The word “unfazed” in line 3 of paragraph E, means___________.
A. refused
B. welcomed
C. not bothered
D. not well received
10. Which of the following statements is TRUE if DRM was scapped?
A. Sony would gain the most profit.
B. More customers would be “l(fā)ocked in”.
C. A sudden increase in piracy would occur.
D. Online-music sales would probably decrease.
Questions 11-14
Complete the notes below.
Choose NO MORE THAN THREE WORDS from Reading Passage 1 for each answer.
Write your answers in boxes 11-14 on your answer sheet.
Mr. Steve Jobs, the boss of Apple, explains the reason why he used to defend DRM, saying that the company was forced to do so: the record companies would make their music accessible to …11...only if they agreed to protect it using DRM; they can still…12…if the DRM system is compromised. He also provides the reason why Apple did not license FairPlay to others: the company relies on them to …13….But now he changes his mind with a possible expectation that Europe’s regulators would not trouble him any more in the future. He proposes that those who are unsatisfactory with the current situation in digital music market should …14… towards persuade the music companies to sell their music DRM-free.
Don't wash those fossils!
Standard museum practice can wash away DNA.
1.Washing, brushing and varnishing fossils — all standard conservation treatments used by many fossil hunters and museum curators alike — vastly reduces the chances of recovering ancient DNA.
2.Instead, excavators should be handling at least some of their bounty with gloves, and freezing samples as they are found, dirt and all, concludes a paper in the Proceedings of the National Academy of Sciences today.
3.Although many palaeontologists know anecdotally that this is the best way to up the odds of extracting good DNA, Eva-Maria Geigl of the Jacques Monod Institute in Paris, France, and her colleagues have now shown just how important conservation practices can be.This information, they say, needs to be hammered home among the people who are actually out in the field digging up bones.
4.Geigl and her colleagues looked at 3,200-year-old fossil bones belonging to a single individual of an extinct cattle species, called an aurochs.The fossils were dug up at a site in France at two different times — either in 1947, and stored in a museum collection, or in 2004, and conserved in sterile conditions at -20 oC.
5.The team's attempts to extract DNA from the 1947 bones all failed.The newly excavated fossils, however, all yielded DNA.
6.Because the bones had been buried for the same amount of time, and in the same conditions, the conservation method had to be to blame says Geigl."As much DNA was degraded in these 57 years as in the 3,200 years before," she says.
Wash in, wash out
7.Because many palaeontologists base their work on the shape of fossils alone, their methods of conservation are not designed to preserve DNA, Geigl explains.
8.The biggest problem is how they are cleaned.Fossils are often washed together on-site in a large bath, which can allow water — and contaminants in the form of contemporary DNA — to permeate into the porous bones."Not only is the authentic DNA getting washed out, but contamination is getting washed in," says Geigl.
9.Most ancient DNA specialists know this already, says Hendrik Poinar, an evolutionary geneticist at McMaster University in Ontario, Canada.But that doesn't mean that best practice has become widespread among those who actually find the fossils.
10.Getting hold of fossils that have been preserved with their DNA in mind relies on close relationships between lab-based geneticists and the excavators, says palaeogeneticist Svante P bo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.And that only occurs in exceptional cases, he says.
11.P bo's team, which has been sequencing Neanderthal DNA, continually faces these problems."When you want to study ancient human and Neanderthal remains, there's a big issue of contamination with contemporary human DNA," he says.
12.This doesn't mean that all museum specimens are fatally flawed, notes P bo.The Neanderthal fossils that were recently sequenced in his own lab, for example, had been part of a museum collection treated in the traditional way.But P bo is keen to see samples of fossils from every major find preserved in line with Geigl's recommendations — just in case.
Warm and wet
13.Geigl herself believes that, with cooperation between bench and field researchers, preserving fossils properly could open up avenues of discovery that have long been assumed closed.
14.Much human cultural development took place in temperate regions.DNA does not survive well in warm environments in the first place, and can vanish when fossils are washed and treated.For this reason, Geigl says, most ancient DNA studies have been done on permafrost samples, such as the woolly mammoth, or on remains sheltered from the elements in cold caves — including cave bear and Neanderthal fossils.
15.Better conservation methods, and a focus on fresh fossils, could boost DNA extraction from more delicate specimens, says Geigl.And that could shed more light on the story of human evolution.
(640 words nature )
Glossary
Palaeontologists 古生物學(xué)家
Aurochs 歐洲野牛
Neanderthal (人類學(xué))尼安德特人，舊石器時(shí)代的古人類。
Permafrost (地理)永凍層
Questions 1-6
Answer the following questions by using NO MORE THAN THREE WORDS for each answer.
1.How did people traditionally treat fossils?
2.What suggestions do Geigl and her colleagues give on what should be done when fossils are found?
3.What problems may be posed if fossil bones are washed on-site? Name ONE.
4.What characteristic do fossil bones have to make them susceptible to be contaminated with contemporary DNA when they are washed?
5.What could be better understood when conservation treatments are improved?
6.The passage mentioned several animal species studied by researchers.How many of them are mentioned?
Questions 7-11
Do the following statements agree with the information given in the passage? Please write TRUE if the statement agrees with the writer FALSE if the statement does not agree with the writer NOT GIVEN if there is no information about this in the passage.
7.In their paper published in the Proceedings of the National Academy of Sciences，Geigl and her colleagues have shown what conservation practices should be followed to preserve ancient DNA.
8.The fossil bones that Geigl and her colleagues studied are all from the same aurochs.
9.Geneticists don't have to work on site.
10.Only newly excavated fossil bones using new conservation methods suggested by Geigl and her colleagues contain ancient DNA.
11.Paabo is still worried about the potential problems caused by treatments of fossils in traditional way.
Questions 12-13
Complete the following the statements by choosing letter A-D for each answer.
12.“This information” in paragraph 3 indicates:
[A] It is critical to follow proper practices in preserving ancient DNA.
[B] The best way of getting good DNA is to handle fossils with gloves.
[C] Fossil hunters should wear home-made hammers while digging up bones.
[D] Many palaeontologists know how one should do in treating fossils.
13.The study conducted by Geigl and her colleagues suggests:
[A] the fact that ancient DNA can not be recovered from fossil bones excavated in the past.
[B] the correlation between the amount of burying time and that of the recovered DNA.
[C] the pace at which DNA degrades.
[D] the correlation between conservation practices and degradation of DNA.
