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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.
SellingDigitalMusicwithoutCopy-protectionMakesSense
A. Itwasuncharacteristicallylow-keyfortheindustry’sgreatestshowman.ButtheessaypublishedthisweekbySteveJobs,thebossofApple,onhisfirm’swebsiteundertheunassumingtitle“ThoughtsonMusic”hasnonethelessprovokedavigorousdebateaboutthefutureofdigitalmusic,whichAppledominateswithitsiPodmusic-playerandiTunesmusic-store.Atissueis“digitalrightsmanagement”(DRM)—thetechnologyguardingdownloadedmusicagainsttheft.SincethereisnocommonstandardforDRM,italsohastheside-effectthatsongspurchasedforonetypeofmusic-playermaynotworkonanother.Apple’sDRMsystem,calledFairPlay,isthemostwidespread.SoitcameasasurprisewhenMr.JobscalledforDRMfordigitalmusictobeabolished.
B. ThisisachangeoftackforApple.IthascomeunderfirefromEuropeanregulatorswhoclaimthatitsrefusaltolicenseFairPlaytootherfirmshas“lockedin”customers.SincemusicfromtheiTunesstorecannotbeplayedonnon-iPodmusic-players(atleastnotwithoutalotoffiddling),anyiTunesbuyerwillbedeterredfromswitchingtoadevicemadebyarivalfirm,suchasSonyorMicrosoft.WhenFrenchlawmakersdraftedabilllastyearcompellingAppletoopenupFairPlaytorivals,thecompanywarnedof“state-sponsoredpiracy”.OnlyDRM,itimplied,couldkeepthepiratesatbay.
C. ThisweekMr.JobsgaveanotherexplanationforhisformerdefenceofDRM:therecordcompaniesmadehimdoit.TheywouldmaketheirmusicavailabletotheiTunesstoreonlyifAppleagreedtoprotectitusingDRM.TheycanstillwithdrawtheircataloguesiftheDRMsystemiscompromised.ApplecannotlicenseFairPlaytoothers,saysMrJobs,becauseitwoulddependonthemtoproducesecurityfixespromptly.AllDRMdoesisrestrictconsumerchoiceandprovideabarriertoentry,saysMrJobs;withoutittherewouldbefarmorestoresandplayers,andfarmoreinnovation.So,hesuggests,whynotdoawaywithDRMandsellmusicunprotected?“Thisisclearlythebestalternativeforconsumers,”hedeclares,“andApplewouldembraceitinaheartbeat.”
D. Whythesuddenchangeofheart?MrJobsseemschieflyconcernedwithgettingEurope’sregulatorsoffhisback.RatherthancomplainingtoAppleaboutitsuseofDRM,hesuggests,“thoseunhappywiththecurrentsituationshouldredirecttheirenergiestowardspersuadingthemusiccompaniestoselltheirmusicDRM-free.”Twoandahalfofthefourbigrecordcompanies,hehelpfullypointsout,areEuropean-owned.MrJobsalsohopestopainthimselfasaconsumerchampion.AppleresentsaccusationsthatithasbecometheMicrosoftofdigitalmusic.
E. Applecanaffordtoembraceopencompetitioninmusicplayersandonlinestores.Consumerswouldgravitatetothebestplayerandthebeststore,andatthemomentthatstillmeansApple’s.MrJobsisevidentlyunfazedbyrivalstotheiPod.Sinceonly3%ofthemusicinatypicaliTuneslibraryisprotected,mostofitcanalreadybeusedonotherplayerstoday,henotes.(AndeventheprotectedtrackscanbeburnedontoaCDandthenre-ripped.)SoApple’sdominanceevidentlydependsfarmoreonbrandingandeaseofusethanDRM-related“lockin”.
F. ThemusicgiantsaretryingDRM-freedownloads.Lotsofsmallerlabelsalreadysellmusicthatway.Havingseenwhichwaythewindisblowing,MrJobsnowwantstobeseennotasDRM’sdefender,butasaconsumerchampionwhohelpedinitsdownfall.Wouldn’titleadtoasurgeinpiracy?No,becausemostmusicisstillsoldunprotectedonCDs,peoplewishingtostealmusicalreadycandoso.Indeed,scrappingDRMwouldprobablyincreaseonline-musicsalesbyreducingconfusionandincompatibility.Withtheleadingonlinestore,Applewouldbenefitmost.MrJobs’sargument,inshort,istransparentlyself-serving.Italsohappenstoberight.
NotestoReadingPassage1
1.low-key:
抑制的，受约束的，屈服的
2.showman:
开展览会的人,出风头的人物
3.unassuming:
谦逊的,不夸耀的,不装腔作势的
4.iPod：
(苹果公司出产的)音乐播放器
5.iTunesstore：
(苹果公司出产的)在线音乐商店
6.getoffperson’sback:
不再找某人的麻烦，摆脱某人的纠缠
7.gravitate:
受吸引，倾向于
8.unfazed:
不再担忧，不被打扰
Questions1-7
DothefollowingstatemetsreflecttheclaimsofthewriterinReadingPassage1?
WriteyouranswerinBoxes1-7onyouranswersheet.
TRUEifthestatementrefletstheclaimsofthewriter
FALSEifthestatementcontradictstheclaimsofthewriter
NOTGIVENifitisimpossbiletosaywhatthewriterthinksaboutthis
1.AppleenjoysacontrollingpositionindigitalmusicmarketwithitsiPodmusic-playerandiTunesmusic-store.
2.DRMisagovernmentdecreeissuedwithapurposetoprotectdownloadedmusicfromtheftbyconsumers.
3.LackofstandardizationinDRMmakessongsboughtforonekindofmusicplayermaynotfunctiononanother.
4.ApplehasbeencriticizedbyEuropeanregulatorssinceithasrefusedtograntalicenseFairPlaytootherfirms.
5.Allmusiccanbeeasilyplayedonnon-iPodmusicdevicesfromSonyorMicrosoftwithouttoomuchfiddling.
6.AppledependsfarmoreonDRMratherthanbrandingforitsdominanceofthedigitalmusicdevices.
7.IfDRMwascancelled,Sonywouldcertainlydominatetheinternationaldigitalmusicmarket.
Questions8-10
ChoosetheappropriatelettersA-Dandwritetheminboxes8-10onyouranswesheet.
8.WhichofthefollowingstatementsaboutMr.Jobs’ideaofDRMisNOTTRUE?
A.DRMplacesrestrictionsonconsumer’choiceofdigitalmusicproductsavailable.
B.DRMcomplesiTunesbuyerstoswitchtoadevicemadebySonyorMicrosoft.
C.DRMconstitutesabarrierforpotentialconsumerstoenterdigitalmusicmarkets.
D.DRMhindersdevelopmentofmorestoresandplayersandtechnicalinnovation.
9.Theword“unfazed”inline3ofparagraphE,means___________.
A.refused
B.welcomed
C.notbothered
D.notwellreceived
10.WhichofthefollowingstatementsisTRUEifDRMwasscapped?
A.Sonywouldgainthemostprofit.
B.Morecustomerswouldbe“lockedin”.
C.Asuddenincreaseinpiracywouldoccur.
D.Online-musicsaleswouldprobablydecrease.
Questions11-14
Completethenotesbelow.
ChooseNOMORETHANTHREEWORDSfromReadingPassage1foreachanswer.
Writeyouranswersinboxes11-14onyouranswersheet.
Mr.SteveJobs,thebossofApple,explainsthereasonwhyheusedtodefendDRM,sayingthatthecompanywasforcedtodoso:therecordcompanieswouldmaketheirmusicaccessibleto…11...onlyiftheyagreedtoprotectitusingDRM;theycanstill…12…iftheDRMsystemiscompromised.HealsoprovidesthereasonwhyAppledidnotlicenseFairPlaytoothers:thecompanyreliesonthemto…13….ButnowhechangeshismindwithapossibleexpectationthatEurope’sregulatorswouldnottroublehimanymoreinthefuture.Heproposesthatthosewhoareunsatisfactorywiththecurrentsituationindigitalmusicmarketshould…14…towardspersuadethemusiccompaniestoselltheirmusicDRM-free.
1There'sadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallontimescalesofaround100,000years-exactlythesameperiodasbetweeniceagesonEarth.Sosaysaphysicistwhohascreatedacomputermodelofourstar'score.
2RobertEhrlichofGeorgeMasonUniversityinFairfax,Virginia,modelledtheeffectoftemperaturefluctuationsinthesun'sinterior.Accordingtothestandardview,thetemperatureofthesun'scoreisheldconstantbytheopposingpressuresofgravityandnuclearfusion.However,Ehrlichbelievedthatslightvariationsshouldbepossible.
3HetookashisstartingpointtheworkofAttilaGrandpierreoftheKonkolyObservatoryoftheHungarianAcademyofSciences.In2005,Grandpierreandacollaborator,Gáborágoston,calculatedthatmagneticfieldsinthesun'scorecouldproducesmallinstabilitiesinthesolarplasma.Theseinstabilitieswouldinducelocalisedoscillationsintemperature.
4Ehrlich'smodelshowsthatwhilstmostoftheseoscillationscanceleachotherout,somereinforceoneanotherandbecomelong-livedtemperaturevariations.Thefavouredfrequenciesallowthesun'scoretemperaturetooscillatearounditsaveragetemperatureof13.6millionkelvinincycleslastingeither100,000or41,000years.Ehrlichsaysthatrandominteractionswithinthesun'smagneticfieldcouldflipthefluctuationsfromonecyclelengthtotheother.
5ThesetwotimescalesareinstantlyrecognisabletoanyonefamiliarwithEarth'siceages:forthepastmillionyears,iceageshaveoccurredroughlyevery100,000years.Beforethat,theyoccurredroughlyevery41,000years.
6MostscientistsbelievethattheiceagesaretheresultofsubtlechangesinEarth'sorbit,knownastheMilankovitchcycles.OnesuchcycledescribesthewayEarth'sorbitgraduallychangesshapefromacircletoaslightellipseandbackagainroughlyevery100,000years.ThetheorysaysthisalterstheamountofsolarradiationthatEarthreceives,triggeringtheiceages.However,apersistentproblemwiththistheoryhasbeenitsinabilitytoexplainwhytheiceageschangedfrequencyamillionyearsago.
7"InMilankovitch,thereiscertainlynogoodideawhythefrequencyshouldchangefromonetoanother,"saysNeilEdwards,aclimatologistattheOpenUniversityinMiltonKeynes,UK.NoristhetransitionproblemtheonlyonetheMilankovitchtheoryfaces.EhrlichandothercriticsclaimthatthetemperaturevariationscausedbyMilankovitchcyclesaresimplynotbigenoughtodriveiceages.
8However,EdwardsbelievesthesmallchangesinsolarheatingproducedbyMilankovitchcyclesarethenamplifiedbyfeedbackmechanismsonEarth.Forexample,ifseaicebeginstoformbecauseofaslightcooling,carbondioxidethatwouldotherwisehavefounditswayintotheatmosphereaspartofthecarboncycleislockedintotheice.ThatweakensthegreenhouseeffectandEarthgrowsevencolder.
9AccordingtoEdwards,thereisnolackofsuchmechanisms."Ifyouaddtheireffectstogether,thereismorethanenoughfeedbacktomakeMilankovitchwork,"hesays."Theproblemnowisidentifyingwhichmechanismsareatwork."ThisiswhyscientistslikeEdwardsarenotyetreadytogiveuponthecurrenttheory."Milankovitchcyclesgiveusiceagesroughlywhenweobservethemtohappen.Wecancalculatewhereweareinthecycleandcompareitwithobservation,"hesays."Ican'tseeanywayoftesting[Ehrlich's]ideatoseewhereweareinthetemperatureoscillation."
10Ehrlichconcedesthis."Ifthereisawaytotestthistheoryonthesun,Ican'tthinkofonethatispractical,"hesays.That'sbecausevariationover41,000to100,000yearsistoogradualtobeobserved.However,theremaybeawaytotestitinotherstars:reddwarfs.Theircoresaremuchsmallerthanthatofthesun,andsoEhrlichbelievesthattheoscillationperiodscouldbeshortenoughtobeobserved.Hehasyettocalculatethepreciseperiodortheextentofvariationinbrightnesstobeexpected.
11NigelWeiss,asolarphysicistattheUniversityofCambridge,isfarfromconvinced.HedescribesEhrlich'sclaimsas"utterlyimplausible".EhrlichcountersthatWeiss'sopinionisbasedonthestandardsolarmodel,whichfailstotakeintoaccountthemagneticinstabilitiesthatcausethetemperaturefluctuations.
Questions1-4
CompleteeachofthefollowingstatementswithOneorTwonamesofthescientistsfromtheboxbelow.
WritetheappropriatelettersA-Einboxes1-4onyouranswersheet.
A.AttilaGrandpierre
B.Gáborágoston
C.NeilEdwards
D.NigelWeiss
E.RobertEhrlich
1....claimsthereadimmerswitchinsidethesunthatcausesitsbrightnesstoriseandfallinperiodsaslongasthosebetweeniceagesonEarth.
2....calculatedthattheinternalsolarmagneticfieldscouldproduceinstabilitiesinthesolarplasma.
3....holdsthatMilankovitchcyclescaninducechangesinsolarheatingonEarthandthechangesareamplifiedonEarth.
4....doesn'tbelieveinEhrlich'sviewpointsatall.
Questions5-9
Dothefollowingstatementsagreewiththeinformationgiveninthereadingpassage?
Inboxes5-9onyouranswersheetwrite
TRUEifthestatementistrueaccordingtothepassage
FALSEifthestatementisfalseaccordingtothepassage
NOTGIVENiftheinformationisnotgiveninthepassage
5.Theiceageschangedfrequencyfrom100,000to41,000yearsamillionyearsago.
6.ThesoleproblemthattheMilankovitchtheorycannotsolveistoexplainwhytheiceagefrequencyshouldshiftfromonetoanother.
7.Carbondioxidecanbelockedartificiallyintoseaicetoeliminatethegreenhouseeffect.
8.SomescientistsarenotreadytogiveuptheMilankovitchtheorythoughtheyhaven'tfiguredoutwhichmechanismsamplifythechangesinsolarheating.
9.BothEdwardsandEhrlichbelievethatthereisnopracticalwaytotestwhenthesolartemperatureoscillationbeginsandwhenends.
Questions10-14
Completethenotesbelow.
ChooseonesuitablewordfromtheReadingPassageaboveforeachanswer.
Writeyouranswersinboxes10-14onyouranswersheet.
Thestandardviewassumesthattheopposingpressuresofgravityandnuclearfusionsholdthetemperature...10...inthesun'sinterior,buttheslightchangesintheearth's...11...alterthetemperatureontheearthandcauseiceagesevery100,000years.ABritishscientist,however,challengesthisviewbyclaimingthattheinternalsolarmagnetic...12...caninducethetemperatureoscillationsinthesun'sinterior.Thesun'scoretemperatureoscillatesarounditsaveragetemperaturein...13...lastingeither100,000or41,000years.Andthe...14...interactionswithinthesun'smagneticfieldcouldflipthefluctuationsfromonecyclelengthtotheother,whichexplainswhytheiceageschangedfrequencyamillionyearsago.
