托福阅读1219.docx

托福阅读1219.docx

《托福阅读1219.docx》由会员分享，可在线阅读，更多相关《托福阅读1219.docx（28页珍藏版）》请在冰豆网上搜索。

托福阅读1219

ResearchersTurnHumanSkinCellsintoBloodCells

-

生物医学领域科学家们的一个梦想如今终于成真。

加拿大麦克马斯特大学的研究人员利用人的皮肤细胞和脱氧核糖核蛋白成功造出了血细胞。

今天的托福考试阅读练习题要关注的就是此项最新研究成果。

　　Oneofthedreamsofbiomedicalscientistsistobeabletotransformadultcellsintootherkindsofcells.Andthusavoidsomeoftheethicalconcernsofworkingwithembryonicstemcells.NowaresearchteamfromMcMasterUniversityinOntariohasannouncedthatthey’vebeenabletotransformhumanskincellsintobloodcells.TheworkwaspublishedonlineonNovember7thbythejournalNature.[EvaSzaboetal.,"Directconversionofhumanfibroblaststomultilineagebloodprogenitors"]

　　Otherresearchinthisareahasrequiredthatcellsofonetypefirstbereturnedtoamoregenerallyundifferentiatedstemcellstate,whichcanintroducefreshproblems.Oncethere,thecellisthenturnedintothetypeoftissuetheresearchersseek.Butinthiscase,thescientistsavoidedthemiddlemancell.Theskinwaschangeddirectlyintowhatappearstobefunctionaladulthumanbloodcells.Thetechniqueinvolvesgeneinsertionbyavirusvectorandexposuretonumerousregulatoryproteins.

　　Thecellshavenotbeentestedinhumanstoseeifthey’retrulyindistinguishablefromthehome-grownkind.Buttheresearchisanotherstepintheefforttocreateneededcelltypesfromeasilyavailableones.

Collectingyourthoughts:

youcandoitinyoursleep!

-

　正在备考托福考试的同学们经常会感觉时间不够用，为了背单词做题常常需要熬夜。

如果睡觉时间也能用来背单词会怎样呢?

　　Itisonethingtolearnanewpieceofinformation,suchasanewphonenumberoranewword,butquiteanothertogetyourbraintofileitawaysoitisavailablewhenyouneedit.

　　AnewstudypublishedintheJournalofNeurosciencebyresearchersattheUniversityofYorkandHarvardMedicalSchoolsuggeststhatsleepmayhelptodoboth.Thescientistsfoundthatsleephelpspeopletorememberanewlylearnedwordandincorporatenewvocabularyintotheir"mentallexicon".

　　Duringthestudy,researcherstaughtvolunteersnewwordsintheevening,followedbyanimmediatetest.Thevolunteerssleptovernightinthelaboratorywhiletheirbrainactivitywasrecordedusinganelectroencephalogram.Atestthefollowingmorningrevealedthattheycouldremembermorewordsthantheydidimmediatelyafterlearningthem,andtheycouldrecognizethemfasterdemonstratingthatsleephadstrengthenedthenewmemories.

　　Thisdidnotoccurinacontrolgroupofvolunteerswhoweretrainedinthemorningandre-testedintheevening,withnosleepinbetween.Anexaminationofthesleepvolunteers'brainwavesshowedthatdeepsleep（slow-wavesleep）ratherthanrapideyemovement（REM）sleeporlightsleephelpedinstrengtheningthenewmemories.

　　Theseresultshighlighttheimportanceofsleepandtheunderlyingbrainprocessesforexpandingvocabulary.LeadauthorJakkeTamminen,said:

"Newmemoriesareonlyreallyusefulifyoucanconnectthemtoinformationyoualreadyknow."hesaidtheirstudyidentifiesthebrainactivityduringsleepthatorganizesnewmemoriesandmakesthosevitalconnectionswithexistingknowledge.

要想学好就该多考试？

-

有句话说得好：

考考考，老师的法宝，分分分，学生的命根。

考试让每个学生都感到压力，因此非常不受欢迎。

但单纯的考试其实非常有助于学生的学习提高。

　　Testsaren'tjustawayforteacherstotorturetheirstudents,accordingtoanewstudythatfindsthebrainencodesbettermentalhintsduringtest-takingthanduringstudyingalone.

　　Althoughmanypeopleviewtestsasawaytomarkandgradestudents'progress,researchhasfoundthattheactofretrievinginformationfrommemoryactuallymakesrememberingiteasier.Inotherwords,testsimprovelearning.

　　ThestudyauthorMaryPyc,apostdoctoralfellowatWashingtonUniversityinSt.Louisandherco-authorKatherineRawsoninvestigatedpiecesofinformationcalled"mediators."Mediatorsareconcepts,ideasorphrasesthatconnectonepieceofinformationtoanother.Tobeagoodmediator,theideahastobebotheasytorememberandeasytolinktotheinformationyou'retryingtoretrieve.

　　Toinvestigatetheeffectoftestingonmediators,PycandRawsonhad118English-speakingparticipantslearn48Swahiliwords.Someofthelearnerstooktestsontheinformationandthengottorestudythematerialbeforebeingtestedagain.Othersonlystudiedandrestudiedwithouttests.

　　Aweekafterlearningthewords,eachgrouptookafinaltest.SometestsrequiredthemtogivetheEnglishtranslationfromtheSwahliiwordalone.AnothergroupgotatestthatgavethemtheSwahiliwordplusthemediatorthey'dusedwhenlearningthewords.Athirdgroupnotonlyhadtotranslatetheword,buttheyalsohadtorememberandwritedowntheirmediatorword.

　　Overall,thegroupthattookpracticetestsdidthreetimesbetterthanthestudy-onlygroup.Inaddition,moretestpracticemadeforbettermediators.Thosewhohadtorecallboththeirmediatorandthetranslationgotscoresaveraging51percentifthey'dbeeninthepretestinggroupandjust34percentifthey'donlystudied.Thosewhodidn'thavetoremembertheirmediator,justlinkittothetranslation,alsodidmuchbetterifthey'dcompletedpracticetests.

：

LaughterisGoodfortheHeart

-

笑是最美的语言，也是最好的健康保养品。

我们今天的托福考试阅读练习题要说的就是笑强大的保健功能。

　　Laughterisgoodfortheheartbecauseitprolongslifewhiledepressionincreasestheriskofanearlydeath,accordingtotwonewstudies.

　　Agoodboutoflaughtereverydayprovidessimilarcardiovascularbenefitsasexercisebecauseitstimulatesthebloodflow,saidMichaelMiller,whoheadedoneresearchteamattheUniversityofMaryland.

　　Ontheotherhand,depression--orthelackoflaughter--isoftenlinkedtounhealthyhabitssuchassmokinganddrugaddictionandincreasestheriskofdeathby44percent,saidWeinJiang,wholedastudyof1,000heartpatientsfortheUniversityofNorthCarolina.

　　Millersaidlaughterproduceda"magnitudeofchange...intheendothelium...similartothebenefitwemightseewithaerobicactivity,butwithouttheaches,painsandmuscletensionassociatedwithexercise"

　　Whilelaughtershouldnotreplaceexercise,hesaid,"Wedorecommendthatyoutrytolaughonaregularbasis.Thirtyminutesofexercisethreetimesaweek,and15minutesoflaughteronadailybasisisprobablygoodforthevascularsystem."

女性小脚更有魅力

-

在封建时代，中国人都认为拥有“三寸金莲”的小脚女人才美，于是历代中国女性都逃脱不了痛苦的缠足厄梦。

直到民国时期孙中山颁布法令后“缠足”才被逐渐禁止。

不过据一项最新研究表明，脚步的大小确实与女性的外貌有关。

这到底是怎么回事呢?

大家首先在下图中选出自己认为更有吸引力的脸。

　　Ifyouchosethefaceontheleft,yousharethetastesofmostheterosexualmen.Itisacompositeface,or"morph",madefromthefacesofeightwomenwithunusuallysmallfeet.Thefaceontherightisamorphofeightwomenwithunusuallylargefeet.

　　It'squiteadifference,isn'tit?

Womenwithsmallerfeethaveprettierfaces,atleastaccordingtothemenwhotookpartinthisstudy.Sodowomenwithlongerthighbonesandnarrowerhips.

　　JeremyAtkinson,anevolutionarypsychologistattheUniversityatAlbany,NewYork,andhiscolleaguesmeasuredhandlength,footlength,thighlengthandhipwidthon60whitefemalecollegestudents.Foreachof16body-partmeasurements,heandhiscolleaguesselectedtheeightwomenwiththeshortestlengthsandtheeightwiththelongest,andconstructedmorphsoftheirfaces.Thesemorphswerethenratedforattractivenessby77heterosexualmalestudents.

　　Themenwerethree-and-a-halftimesaslikelytopicktheshort-footedmorphasmoreattractive,andalmost10timesaslikelytosayitwasmorefeminine,Atkinsonandhiscolleaguesfound.Similarly,theyweremorethan11timesaslikelytopickthenarrow-hippedmorphasmoreattractive,andeighttimesaslikelytochoosethelong-thighedmorph.

　Atkinsonthinksmenfindthesefeaturesattractivebecausetheyserveasmarkersofahealthychildhood.Biologistsknowthatstressandpoornutritionduringfoetaldevelopmentandpubertycanaffectsexhormonelevelsandcauseearlierpuberty.

　　Thiscanleavesuchwomenrelativelyshortandstout,whilethosewithamorebenignchildhoodcontinuegrowingforlonger,andattainaslenderer,morestereotypicallyfemininefaceandbody,whichmostmenfindmoreattractive.

世界上最小国家正在出售

-

　许多普通人都曾有过成为一国元首一国之君的梦想，如今购买一个世界上最小的国家就能圆梦。

　　Forsale:

theworld'ssmallestcountrywithitsownflag,stamps,currencyandpassports.

　　Applytoprincemichaelofsealandifyouwanttorunyourownnation,evenifitisjustawartimefortperchedontwoconcretetowersinthenorthsea.

　　BuiltinworldwarTwoasananti-aircraftbasetorepelgermanbombers,thederelictplat-formwastakenover40yearsagobyretiredarmymajorPaddyRoyBateswhowenttolivetherewithhisfamily.

　　Hedeclaredtheplatform,perchedsevenmilesofftheeastcoastofenglandandjustoutsidebritain'sterritorialwaters,tobetheprincipalityofsealand.

　　Theself-styledprinceRoyadoptedaflag,choseanationalanthemandmintedsilverandgoldcoins.

　　ThefamilysawoffattemptsbyBritain'sRoyalNavytoevictthemandalsoanattemptin1978byagroupofgermananddutchbusinessmentoseizesealandbyforce.

　　Roy,85,nowlivesinSpainandhissonMichaeltoldBBCRadiohisfamilyhadbeenapproachedbyestateagentswithclients"whowantedabitmorethanabitofrealestate,theywantedautonomy."

“发现号”再次推迟发射

-

已经为NASA服务了26年的“发现号”如今即将开始自己的最后一次航行，不过开始此次航行似乎并不顺利，最近因为漏油，“发现号”的发射时间再次推迟。

　　ThefinalmissionofthespaceshuttleDiscoveryhasbeenpostponedagainbecauseofafuelleak.

　　After26yearsofservice,thevehicleisduetomakeonelastflighttotheInternationalSpaceStation（ISS）beforebeingretiredtoamuseum.

　　NasahasstruggledallweektogetDiscoveryofftheground,frustratedbypoorweatherandtechnicalproblems.

　　EscapinghydrogendetectedmidwaythroughfuellingleftNasanochoicebuttostandDiscoverydown