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高中英语阅读理解科技类二Medicaldrugssometimescausemoredamagethantheycure.Onesolutiontothisproblemistoputthedrugsinsideacapsule,protectingthemfromthebody—andthebodyfromthem—untiltheycanbereleasedatjusttherightspot.Therearelotsofwaystotrigger(引发)thisrelease,includingchangingtemperature,acidity,andsoon.Buttriggerscancomewiththeirownrisks---burns,forexample.Now,researchersinCaliforniahavedesignedwhatcouldbeaharmlesstriggertodate:shiningnear-infraredlight(NIR，近红外钱)onthedruginthecapsule.Theideaofsuinglighttoliberatethedruginthecapsuleisn’tnew.Researchersaroundtheglobehavedevelopedpolymers(聚合物)andothermaterialsthatbegintobreakdownwhentheyabsorbeitherultraviolet(UV，紫外线)orvisiblelight.ButtissuesalsoreadilyabsorbUVandvisiblelight,whichmeansthedrugreleasecanbetriggeredonlyneartheskin,wherethelightcanreachthecapsule.NIRlightlargelypassesthroughtissues,soresearchershavetriedtouseitasatrigger.Butfewcompounds(化合物)absorbNIRwellandgothroughchemicalchanges.ThatchangedlastyearwhenAdahAlmutairi,achemistattheUniversityofCalifornia,SanDiego,reportedthatsheandhercolleagueshaddesignedapolymerthatbreaksdownwhenitabsorbsNIRlight.TheirpolymerusedacommerciallyavailableNIR-absorbinggroupcalledo-nitroberizyl(ONB).Whentheycatchthelight,ONBgroupsfalloffthepolymer,leadingtoitsbreakdown.ButONBisonlyaso-soNIRabsorber,anditcouldbepoisonoustocellswhenitseparatesfromthepolymer.SoAlmutairiandhercolleaguesreportedcreatinganewmaterialforcapsulesthat’sevenbetter.Thisoneconsistsofalongchainofcompoundscalledcresolgroupslinkedinapolymer.Cresolcontainsreactive(易反应的)componentsthatmakeithighlyunstableinitspolymericform,afeatureAlmutairiandhercolleaguesusetotheiradvantage.Afterpolymerizingthecresols,theycapeachreactivecomponentwithalight-absorbingcompoundcalledBhc.WhentheBhcsabsorbNIRlight,thereactivecomponentwithalight-absorbingcompoundcalledBhc.WhentheBhcsabsorbNIRlight,thereactivegroupsareexposedandbreakthelongpolymerintotwoshortchains.Shiningadditionallightcontinuesthisbreakdown,potentiallyreleasinganydrugsinthecapsule.What’smore,Almutairisays,Bhcis10timesbetteratabsorbingNIRthanisONBandisnotpoisonoustocells.1.Accordingtothepassage,whichofthefollowingcouldbethebesttrigger?A.TemperaturechangeB.NIRlight.C.Aciditychange.D.UVlight.2.WhyisONBunsatisfactory?A.ItbreaksdownwhenitabsorbsNIRlight.B.Itfallsoffthepolymerandtriggersdrugrelease.C.Ithasnotcomeontothemarketuptillnow.D.Itisnoteffectiveenoughandcouldbepoisonous.3.Whichwordcanbeusedtocompetethefollowingprocessofchanges?A.protectedB.formedC.exposedD.combinedBhcsabsorbNIR.Partofthecresolis______Polymerbreaksdown.Drugisreleased.Ifadiversurfacestooquickly,hemaysufferthebends.Nitrogen(氮)dissolved(溶解)inhisbloodissuddenlyliberatedbythereductionofpressure.Theconsequence,ifthebubbles(气泡)accumulateinajoint,issharppainandabentbody—thusthename.Ifthebubblesforminhislungsorhisbrain,theconsequencecanbedeath.Otherair-breathinganimalsalsosufferthisdecompression(减压)sicknessiftheysurfacetoofast:whales,forexample.Andso,longago,didichthyosaurs.Thattheseancientseaanimalsgotthebendscanbeseenfromtheirbones.Ifbubblesofnitrogenforminsidethebonetheycancutoffitsbloodsupply.Thiskillsthecellsinthebone,andconsequentlyweakensit,sometimestothepointofcollapse.Fossil(化石)bonesthathavecavedinonthemselvesarethusasignthattheanimaloncehadthebends.BruceRothschildoftheUniversityofKansasknewallthiswhenhebeganastudyofichthyosaurbonestofindouthowwidespreadtheproblemwasinthepast.Whatheparticularlywantedtoinvestigatewashowichthyosaursadaptedtotheproblemofdecompressionoverthe150millionyears.Tothisend,heandhiscolleaguestraveledtheworld’snatural-historymuseums,lookingathundredsofichthyosaursfromtheTriassicperiodandfromthelaterJurassicandCretaceousperiods.Whenhestarted,heassumedthatsignsofthebendswouldberarerinyoungerfossils,reflectingtheirgradualevolutionofmeasurestodealwithdecompression.Instead,hewasastonishedtodiscovertheopposite.Morethan15%ofJurassicandCretaceousichthyosaurshadsufferedthebendsbeforetheydied,butnotasingleTriassicspecimen(标本)showedevidenceofthatsortofinjury.Ifichthyosaursdidevolveananti-decompressionmeans,theyclearlydidsoquickly—and,moststrangely,theylostitafterwards.ButthatisnotwhatDrRothschildthinkshappened.Hesuspectsitwasevolutioninotheranimalsthatcausedthechange.Whalesthatsufferthebendsoftendosobecausetheyhavesurfacedtoescapeapredator(捕食动物)suchasalargeshark.OneofthefeaturesofJurassicoceanswasanabundanceoflargesharksandcrocodiles,bothofwhichwerefondofichthyosaurlunches.Triassicoceans,bycontrast,weremercifullyshark-andcrocodile-free.IntheTriassic,then,ichthyosaursweretopofthefoodchain.IntheJurassicandCretaceous,theywereprey(猎物)aswellaspredator—andoftenhadtomakeaspeedyexitasaresult.1.Whichofthefollowingisatypicalsymptomofthebends?A.Atwistedbody.B.Agradualdecreaseinbloodsupply.C.Asuddenreleaseofnitrogeninblood.D.Adropinbloodpressure.2.ThepurposeofRothschild’sstudyistosee_____.A.howoftenichthyosaurscaughtthebendsB.howichthyosaursadaptedtodecompressionC.whyichthyosaursbenttheirbodiesD.whenichthyosaursbroketheirbones3.Rothschild’sfindingstatedinPara