Rogue theory of smell gets a boost

1.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.That's 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 body's 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 doesn't 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.Turin's explanation for these smelly facts invokes the idea that the smell signal in olfactory receptor proteins is triggered not by an odour molecule's 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.Turin's 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 Stoneham's colleague, Andrew Horsfield.

10.Stoneham says that when he first heard about Turin's idea, while Turin was himself based at UCL, "I didn't believe it".But, he adds, "because it was an interesting idea, I thought I should prove it couldn't 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 that's different from a proof of Turin's idea."So far things look plausible, but we need proper experimental verification.We're 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.

Questions 5-9

Complete the sentences below with words from the passage.Use NO MORE THAN THREE WORDS for each answer.

5.The hypothesis that we smell by sensing the molecular vibration was made by ______.

6.Turin's company is based in ______.

7.Most scientists believed that our nose works in the same way as our ______.

8.Different isotopes can smell different when ______ weigh differently.

9.According to Audrew Horsfield, it is still to be proved that ______ could really occur in human nose.

查看答案
正确答案:

5.Luca Turin

6.Virginia

7.tongue

8.the atoms

9.vibration-assisted electron tunneling

答案解析:

5、文章第二,三和七段均可看出Luca的理论即人类的鼻子是通过感觉气味分子的震动来分辨气味的。

6、见第四段。

7、见第五段“Thismolecular'lockandkey'processisthoughttoliebehindawiderangeofthebody'sdetectionsystems:itishowsomepartsoftheimmunesystemrecogniseinvaders,forexample,andhowthetonguerecognizessometastes.”

8、见第八段“Thiswouldexplainwhyisotopescansmelldifferent:theirvibrationfrequenciesarechangediftheatomsareheavier.”

9、见第九段“"Thequestioniswhetherthisispossibleinthenose,"saysStoneham'scolleague,AndrewHorsfield.”句中的代词“this”指句首的“vibration-assistedelectrontunneling”。

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How a Frenchman is reviving McDonald’s in Europe

A. When Denis Hennequin took over as the European boss of McDonald’s in January 2004, the world’s biggest restaurant chain was showing signs of recovery in America and Australia, but sales in Europe were sluggish or declining. One exception was France, where Mr Hennequin had done a sterling job as head of the group’s French subsidiary to sell more Big Macs to his compatriots. His task was to replicate this success in all 41 of the European countries where anti-globalisers’ favourite enemy operates.

B. So far Mr Hennequin is doing well. Last year European sales increased by 5.8% and the number of customers by 3.4%, the best annual results in nearly 15 years. Europe accounted for 36% of the group’s profits and for 28% of its sales. December was an especially good month as customers took to seasonal menu offerings in France and Britain, and to a promotion in Germany based on the game of Monopoly.

C. Mr Hennequin’s recipe for revival is to be more open about his company’s operations, to be “locally relevant”, and to improve the experience of visiting his 6,400 restaurants. McDonald’s is blamed for making people fat, exploiting workers, treating animals cruelly, polluting the environment and simply for being American. Mr Hennequin says he wants to engage in a dialogue with the public to address these concerns.

D. He introduced “open door” visitor days in each country which became hugely popular. In Poland alone some 50,000 visitors came to McDonald’s through the visitors’ programme last year. The Nutrition Information Initiative, launched last year, put detailed labels on McDonald’s packaging with data on calories, protein, fat, carbohydrates and salt content. The details are also printed on tray-liners.

E. Mr Hennequin also wants people to know that “McJobs”, the low-paid menial jobs at McDonald’s restaurants, are much better than people think. But some of his efforts have backfired: last year he sparked a controversy with the introduction of a “McPassport” that allows McDonald’s employees to work anywhere in the European Union. Politicians accused the firm of a ploy to make cheap labour from eastern Europe more easily available to McDonald’s managers across the continent.

F. To stay in touch with local needs and preferences, McDonald’s employs local bosses as much as possible. A Russian is running McDonald’s in Russia, though a Serb is in charge of Germany. The group buys mainly from local suppliers. Four-fifths of its supplies in France come from local farmers, for example. (Some of the French farmers who campaigned against the company in the late 1990s subsequently discovered that it was, in fact, buying their produce.) And it hires celebrities such as Heidi Klum, a German model, as local brand ambassadors.

G. In his previous job Mr Hennequin established a “design studio” in France to spruce up his company’s drab restaurants and adapt the interior to local tastes. The studio is now masterminding improvements everywhere in Europe. He also set up a “food studio”, where cooks devise new recipes in response to local trends.

H. Given France’s reputation as the most anti-American country in Europe, it seems odd that McDonald’s revival in Europe is being led by a Frenchman, using ideas cooked up in the French market. But France is in fact the company’s most profitable market after America. The market where McDonald’s is weakest in Europe is not France, but Britain.

I. “Fixing Britain should be his priority,” says David Palmer, a restaurant analyst at UBS. Almost two-thirds of the 1,214 McDonald’s restaurants in Britain are company-owned, compared with 40% in Europe and 15% in America. The company suffers from the volatility of sales at its own restaurants, but can rely on steady income from franchisees. So it should sell as many underperforming outlets as possible, says Mr Palmer.

J. M.Mark Wiltamuth, an analyst at Morgan Stanley, estimates that European company-owned restaurants’ margins will increase slightly to 16.4% in 2007. This is still less than in the late 1990s and below America’s 18-19% today. But it is much better than before Mr Hennequin’s reign. He is already being tipped as the first European candidate for the group’s top job in Illinois. Nobody would call that a McJob.

Notes to Reading Passage 1

1.sterling高质量的

e.g. He has many sterling qualities. 他身上有许多优秀的品质。

2. menial 不体面的, 乏味的(工作、职业)

3. spruce up打扮整齐、漂亮、装饰

4. mastermind指挥、谋划(一个计划或活动)

e.g. The police know who masterminded the robbery.警察知道是谁策划了那次抢劫。

5. underperform表现不佳表现出低于标准的工作水平、企业出现亏本

Questions 1-6

Do the following statements reflect the claims of the writer in Reading Passage 1?

Write your answer in Boxes 1-6 on your answer sheet.

TRUE if the statement reflects the claims of the writer

FALSE if the statement contradicts the claims of the writer

NOT GIVEN if it is impossible to say what the writer thinks about this

1. McDonald was showing the sign of recovery in all European countries except France after Denis Hennequin took office as the boss of Euro-markets.

2. Starting from last year, detailed labels are put on McDonald’s packaging and detailed information is also printed on tray-liners.

3. France is said to be the most anti-American country in Europe, but the ideas of the “open door” visiting days and “McPassport” are invented in the French market.

4. Britain possesses the weakest McDonald market among European countries and approximately 1214 McDonald’s restaurants are company-owned.

5. According to David Palmer, a restaurant analyst at UBS, David Hennequin should treat the problem about McDonald in Britain as the most important thing.

6. David Palmer suggested that the management of McDonalod in Italy should sell as many its outlets which lose money in business as possible for revival.

Questions 7-10

Choose the appropriate letters A-D and write them in boxes 7-10 on your answe sheet.

7. The word “sterling” in line 3 of Paragraph A means__________.

A. difficult

B. menial

C. terrible

D. excellent

8. Which of the following statements on the accusation of MacDonald is NOT TRUE?

A. It tends to make people fat.

B. Its operations are very vague.

C. It tends to exploit workers.

D. It tends to treat animals cruelly.

9. Which of the following measures taken by Denis Hennequin produced undesired result?

A. “Food Studio” scheme.

B. “Open Door” visitor days.

C. The “McPassport” scheme.

D. The Nutrition Information Initiative.

10. What did Denis Hennequin do so as to respond to local trends?

A. set up a “Food Studio” .

B. established a “Design Studio”.

C. hired celebrities as local brand ambassadors.

D. employed local bosses as much as possible.

Questions 11-14

Complete each of the following statements (Questions 11-14) with words or number taken from Reading Passage 1.

Write NO MORE THAN THREE WORDS for each answer.

Write your answers in boxes 11-14 on your answer sheet.

11. After January 2004, McDonald was making improvement following a period of slump in America and Australia, but sales in Europe were ………………………….

12. Business of McDonald in France and Britain was particularly good in December since customers took to ……………………………..

13. Compared with other countries, France is McDonald’s ………………………. next to America.

14. ……………………. of McDonald’s restaurants in America are companied–owned and the figure is much lower than that in Britain.

newweapontofightcancer

1.Britishscientistsarepreparingtolaunchtrialsofaradicalnewwaytofightcancer,whichkillstumoursbyinfectingthemwithviruseslikethecommoncold.

2.Ifsuccessful,virustherapycouldeventuallyformathirdpillaralongsideradiotherapyandchemotherapyinthestandardarsenalagainstcancer,whileavoidingsomeofthedebilitatingside-effects.

3.LeonardSeymour,aprofessorofgenetherapyatOxfordUniversity,whohasbeenworkingonthevirustherapywithcolleaguesinLondonandtheUS,willleadthetrialslaterthisyear.CancerResearchUKsaidyesterdaythatitwasexcitedbythepotentialofProfSeymour’spioneeringtechniques.

4.Oneofthecountry’sleadinggeneticists,ProfSeymourhasbeenworkingwithvirusesthatkillcancercellsdirectly,whileavoidingharmtohealthytissue."Inprinciple,you’vegotsomethingwhichcouldbemanytimesmoreeffectivethanregularchemotherapy,"hesaid.

5.Cancer-killingvirusesexploitthefactthatcancercellssuppressthebody’slocalimmunesystem."Ifacancerdoesn’tdothat,theimmunesystemwipesitout.Ifyoucangetavirusintoatumour,virusesfindthemaverygoodplacetobebecausethere’snoimmunesystemtostopthemreplicating.Youcanregarditasthecancer’sAchilles’heel."

6.Onlyasmallamountofthevirusneedstogettothecancer."Theyreplicate,yougetamillioncopiesineachcellandthecellburstsandtheyinfectthetumourcellsadjacentandrepeattheprocess,"saidProfSeymour.

7.Preliminaryresearchonmiceshowsthatthevirusesworkwellontumoursresistanttostandardcancerdrugs."It’saninterestingpossibilitythattheymayhaveanadvantageinkillingdrug-resistanttumours,whichcouldbequitedifferenttoanythingwe’vehadbefore."

8.Researchershaveknownforsometimethatvirusescankilltumourcellsandsomeaspectsoftheworkhavealreadybeenpublishedinscientificjournals.Americanscientistshavepreviouslyinjectedvirusesdirectlyintotumoursbutthistechniquewillnotworkifthecancerisinaccessibleorhasspreadthroughoutthebody.

9.ProfSeymour’sinnovativesolutionistomaskthevirusfromthebody’simmunesystem,effectivelyallowingthevirusestodowhatchemotherapydrugsdo-spreadthroughthebloodandreachtumourswherevertheyare.Thebighurdlehasalwaysbeentofindawaytodelivervirusestotumoursviathebloodstreamwithoutthebody’simmunesystemdestroyingthemontheway.

10."Whatwe’vedoneismakechemicalmodificationstothevirustoputapolymercoataroundit-it’sastealthviruswhenyouinjectit,"hesaid.

11.Afterthestealthvirusinfectsthetumour,itreplicates,butthecopiesdonothavethechemicalmodifications.Iftheyescapefromthetumour,thecopieswillbequicklyrecognisedandmoppedupbythebody’simmunesystem.

12.Thetherapywouldbeespeciallyusefulforsecondarycancers,calledmetastases,whichsometimesspreadaroundthebodyafterthefirsttumourappears."There’sanawfulstatisticofpatientsinthewest...withmalignantcancers;75%ofthemgoontodiefrommetastases,"saidProfSeymour.

13.Twovirusesarelikelytobeexaminedinthefirstclinicaltrials:adenovirus,whichnormallycausesacold-likeillness,andvaccinia,whichcausescowpoxandisalsousedinthevaccineagainstsmallpox.Forsafetyreasons,bothwillbedisabledtomakethemlesspathogenicinthetrial,butProfSeymoursaidheeventuallyhopestousenaturalviruses.

14.Thefirsttrialswilluseuncoatedadenovirusandvacciniaandwillbedeliveredlocallytolivertumours,inordertoestablishwhetherthetreatmentissafeinhumansandwhatdoseofviruswillbeneeded.Severalmoreyearsoftrialswillbeneeded,eventuallyalsoonthepolymer-coatedviruses,beforethetherapycanbeconsideredforuseintheNHS.Thoughtheapproachwillbeexaminedatfirstforcancersthatdonotrespondtoconventionaltreatments,ProfSeymourhopesthatonedayitmightbeappliedtoallcancers.

Questions1-6

Dothefollowingstatementsagreewiththeinformationgiveninthereadingpassage?Forquestions1-6write

TRUEifthestatementagreeswiththeinformation

FALSEifthestatementcontradictstheinformation

NOTGIVENifthereisnoinformationonthisinthepassage

1.Virustherapy,ifsuccessful,hasanadvantageineliminatingside-effects.

2.CancerResearchUKisquitehopefulaboutProfessorSeymour’sworkonthevirustherapy.

3.Viruscankillcancercellsandstopthemfromgrowingagain.

4.Cancer’sAchilles’heelreferstothefactthatvirusmaystaysafelyinatumorandreplicate.

5.Toinfectthecancercells,agooddealofvirusesshouldbeinjectedintothetumor.

6.Researchesonanimalsindicatethatviruscouldbeusedasanewwaytotreatdrug-resistanttumors.

Question7-9

Basedonthereadingpassage,choosetheappropriateletterfromA-Dforeachanswer.

7.Informationaboutresearchesonviruseskillingtumorcellscanbefound

(A)onTV

(B)inmagazines

(C)oninternet

(D)innewspapers

8.Totreattumorsspreadingoutinbody,researcherstryto

(A)changethebody’immunesystem

(B)injectchemotherapydrugsintobloodstream.

(C)increasetheamountofinjection

(D)disguisethevirusesonthewaytotumors.

9.Whenthechemicalmodifiedvirusintumorreplicates,thecopies

(A)willsoonescapefromthetumorandspreadout.

(B)willbewipedoutbythebody’simmunesystem.

(C)willbeimmediatelyrecognizedbytheresearchers.

(D)willeventuallystopthetumorfromspreadingout.

Questions10-13

Completethesentencesbelow.Chooseyouranswersfromthelistofwords.Youcanonlyuseeachwordonce.

NBTherearemorewordsinthelistthanspacessoyouwillnotusethemall.

Inthefirstclinicaltrials,scientistswilltryto……10……adenovirusandvaccinia,soboththeviruseswillbelesspathogenicthanthe……11…….Theseuncoatedviruseswillbeapplieddirectlytocertainareastoconfirmsafetyonhumanbeingsandtheright……12……needed.Theexperimentswillfirstlybe……13……tothetreatmentofcertaincancers

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