英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文

英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文xxx公司英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文文件編號(hào)：文件日期：修訂次數(shù)：第1.0次更改批準(zhǔn)審核制定方案設(shè)計(jì)，管理制度英語(yǔ)聽(tīng)力聽(tīng)寫練習(xí)原文〈2014.7〉第一集1.OceanPlasticParticlesCouldGetinGillsSeacreatureseatplasticdumpedintheocean,buttheyalsomightbeaccumulatingplasticbysuckinguptinyparticleswiththeirsiphonsandgills.ChristopherIntagliatareports.Therearenowatleastfivemajorgarbagepatchesintheworld'soceans,andmuchofthattrashisplastic.Butlastmonthresearcherssaidtheycanonlyaccountforonepercentoftheplasticthey'dexpecttofindintheoceans.So,where'dtherestofitgo?Well,animalseatsomeofit.Plastichasbeenfoundinturtles,seabirds,fish,plankton,shellfish,evenbottom-feedinginvertebrates.Butthere'sanotherwayseacreaturesmightbeaccumulatingplastic:bysuckinguptinyplasticparticleswiththeirsiphonsandgills.Researchersaddedcommonshorecrabs—Carcinusmaenas—totanksofseawatercontainingmillionsoftinyplasticparticles,just10micronsindiameter.After16hours,allthecrabshadplasticlodgedintheirgills.Andtheparticlesstuckaroundforuptothreeweeks,too.TheresultsareinthejournalEnvironmentalScienceandTechnology.[AndrewJ.R.Wattsetal,UptakeandRetentionofMicroplasticsbytheShoreCrabCarcinusmaenas]Thelongerplasticsitsinananimal,researcherssay,thebetterthechancesitwilltravelupthefoodchain.Meaningallourplasticwastecouldcomebacktobiteus—orratherbebittenbyus."Ofcourseweeatmusselswhole,withouttheshells.Butwe'repotentiallyeatingplastic,ifthey'refromasitewherethere'splasticpresent."LeadresearcherAndrewWatts,oftheUniversityofExeter."Wedon'tknowhowmuchplasticwehaveinourstomachs…chancesarewedohavesome."—ChristopherIntagliata2.Salmonella'sFavoriteFoodCouldBeItsAchilles'HeelSalmonella'sprimaryfuelsourceisthemoleculefructose-asparagine.Starvingitofthatfuelinaninfectedpersoncouldkillitwithoutharmingbeneficialgutbacteria.KarenHopkinreportsSummer’shereandwithitcomepicnics,barbecuesandofcoursesalmonella.Thegermisnotoriousforcontaminatingavarietyoffavoritewarm-weatherfoods.Butthebacteria’spalateismorelimitedthanours.Oncesalmonellamakesitswayintoyoursystem,itreliesonasingleunusualnutrienttosurvive.That’saccordingtoastudyinthejournalPLoSPathogens.[MohamedM.Alietal,Fructose-AsparagineIsaPrimaryNutrientduringGrowthofSalmonellaintheInflamedIntestine]Mostpeopletoughitoutwhentheygetfoodpoisoningfromsalmonella.That’sbecausetreatmentwithantibioticswouldeliminatetheinfection,butalsogetridofthegutbacteriathatpromotegoodhealth.Tofigureouthowtotargetsalmonellaspecifically,researchersscreenedforgenesvitalforthemicrobe’ssurvivalduringtheactivephaseofinfection.Andtheyidentifiedaclusteroffivegenesthatworktogethertoallowthebacteriatodigestamoleculecalledfructose-asparagine.Nootherorganismsareknowntousethischemicalforfuel,sostarvingsalmonellaofitcouldbeanewstrategyforfightingthisfoodbornebugwhileleavingdesirableintestinalinhabitantsunharmed.Next,theresearchersplantoseewhichfoodscontainlargeamountsofsalmonella’sgo-tosnack.Butplease,don’tsendunsolicitedsamplesofAuntAgnes’seggsalad.—KarenHopkin3.EducationLevelLinkedtoNearsightednessInaGermanstudy,halfofthosewithauniversitydegreeweremyopiccomparedwithlessthanaquarteroffolkswhoquitafterhighschoolorsecondaryschool.KarenHopkinreportsNothingsays“overeducatedegghead”likeapairofcoke-bottleglasses.Butevenclichéssometimeshitthenerdonthehead.Becauseanewstudyfindsthatnearsightednessislinkedtothenumberofyearsspentinschool.ThefindingscanbeviewedinthejournalOphthalmology.[AlirezaMirshahietal,MyopiaandLevelofEducation]Inthepastcentury,theprevalenceofmyopia—science-speakforbeingabletoseeonlywhat’srightinfrontofyou—hasbeenontherise.Somuchsothatitcan’tallbeblamedongeekygenes.Tonaildownthepotentialenvironmentalinfluences,researchersfocusedontheclassroom.Theygaveeyeexamstonearly5000GermansubjectsinaprojectcalledtheGutenbergHealthStudy.Theresearchersfoundthatindividualswith13yearsofeducationweremoremyopicthanthosewhodidn’tgetpastprimaryschool.Andmorethanhalfofthosewithauniversitydegreecoulduseasetofspecs,comparedtolessthanaquarterofthefolkswhoquitafterhighschoolorsecondaryschool.Allthatlearningtakesalotofreading.Whichitselfisassociatedwithnearsightedness.Orthenearsightedmaygravitatetowardpursuitseasiertosee—likehittingthebooks.Eitherway,seemsthatbeingagoodstudentmaynotrequiregreatpupils.—KarenHopkin4.GiveUsThisDaytheBreadWheatGenomeApreliminarymapofthebreadwheatgenomeincludesthelocationsofmorethan75,000genes.CynthiaGraberreportsWheathelpedcreatecivilizationintheMiddleEast.It’sastaplecropfor30percentoftheworld’spopulation.Andnow,withthepublicationoffourarticlesinthejournalScience,we’reclosetoadetailedunderstandingofthebreadwheatgenome.[KellyeEversoleetal,Slicingthewheatgenome]Wheatistoughtosequence.It’sgonethroughmultiplehybridizations,makingitsgenomefivetimeslargerthanahumanone.Plustherearemanyredundancies:morethan80percentofthegenomeismadeofrepeatedDNAsequences.Sothetypicalwhole-genomeshotgunapproach—breakinggenomesintosegmentsandthenreassemblingthem—doesn’tworkforwheat.Instead,aninternationalconsortiumdevisedanotherstrategy,involvingphysicallymappingindividualchromosomesandchromosomearms.Onepaperdetailsadraftoftheentiregenomeofbreadwheat.Anotheridentifiesallthegenesonthelargestoftheplant’s21chromosomes.Some75,000geneshavebeenmapped.Themethodsinthesecondpaperwillhelpscientistsmaptheremainingchromosomes.Theysayitshouldtakeanotherthreeyears.Knowingexactlywhichgenesareresponsiblefortalentssuchastoleratingdroughtorimprovingyieldsshouldallowresearcherstominethegenomeandtoquicklyproducenewandbetterwheatvarietiestobringusourdailybread.—CynthiaGraber5.SupercooledOrgansCouldStretchTimetoTransplantLivertransplanttimefromhumandonortopatientislimitedto12hours,butratsthatgotliversspeciallystoredforthreedaysweregoingstrongthreemonthslater.CynthiaGraberreportsIfyouneedanewliver,doctorshaveabouttwelvehourstotransportitfromadonor.Thattickingclockseverelylimitstheabilityofdoctorstogetorganstopatients.Nowresearchershavedemonstratedamethodthatkeptratliversviableuptofourdays.Thescientistsloweredtheliverstobelowfreezingtemperatures,whilefloodingthetissuewithantifreezechemicalstopreventtheformationofdamagingicecrystals.Butsuchcoolingaloneisnotsufficient,dueinparttotheliver’swidevarietyofcelltypesandfunctions.Sotheresearchersalsousedmachineperfusion:astheliverswerecooledtheywereflushedwithsolutionsthatkeptthemoperational.Theywereperfusedagainastheywerebroughtbacktoabove-freezingtemps.Alltheratsthatwereimplantedwith3-day-oldliverssurvivedforthreemonths.Nearly60percentoftheratswithfour-day-oldliverssurvived.Incontrast,noratsthatreceived3-and4-day-oldliverspreservedbycurrentlyusedmethodssurvived.[TimA.Berendsenetal,Supercoolingenableslong-termtransplantationsurvivalfollowing4daysofliverpreservation,inNatureMedicine]Thisworkisanearlysteptowardcreatingasystemthatcouldworkinhumans,whichwoulddramaticallyimprovethechancesofgettingorganstopeoplewhodesperatelyneedthem.—CynthiaGraber6.Space-BasedDataCollectionBetterPredictsFloodsSatellitedatacanhelpgeologistspredictmajorfloodsupto11monthsinadvanceinareaswheresnowmeltorgroundwaterisasignificantcontributor.CynthiaGraberreportsWanttoknowwhere—andwhen—thenextmajorriverfloodwillhit

Justlookup,tothesatellites.

Conventionalestimatesofrivervolumecomefromrainfall,ofcourse,andfrommeasurementofthewaterthatseepsfromsoilandgroundwaterreserves.ButNASA’sGRACEsatellites,forGravityRecoveryandClimateExperiment,canpickupchangesinthegravityfieldinagivenriverbasin.Themorewaterinthebasin,thehigherthegravitysignal.ScientistsusedGRACEresultsfrom2003to2012toseeiftheycouldhavepredictedthe500-yearfloodingeventintheMissouriRiverbasinin2011.Precedingthefloodweretwosignificantstorms,recordsnowmelt,saturatedsoilsandparticularlyhighgroundwater.WithGRACEdata,theresearchersfoundthattheycouldhavepredictedtheMissouriRiverfloodsmonthsbeforecurrentpredictionmodels.Theysaythatthetechniquecouldbeusedtoforecastfloodsupto11monthsbeforesucheventstakeplaceinareaswheresnowmeltorgroundwaterisasignificantcontribution.TheresearchwaspublishedinthejournalNatureGeoscience.[J.T.Reager,B.F.ThomasandJ.S.Famiglietti,RiverbasinfloodpotentialinferredusingGRACEgravityobservationsatseveralmonthsleadtime]Snowmeltandmajorrainstormsarepredictedtoincreasewithclimatechange.Whichputsapremiumonbetterfloodprediction.—CynthiaGraber7.MobilePhonesCarryOwners'MicrobiomesThebacteriafoundonsomeone'smobilephoneisagoodmatchforthemostcommonkindsofbacteriathatliveontheirhands.ChristopherIntagliatareportsThisyear,thenumberofmobilephonesoncellnetworksisexpectedtosurpasstheEarth'spopulation."Morepeoplenowowncellphonesthanactuallyhaveaccesstoworkingtoilets."JamesMeadow,amicrobialecologistattheUniversityofOregon.Hiddeninthedataistherealitythatsomepeopleworkontheirphones…ontoilets.Ifthatgrossesyouout,considerthis:"Soitturnsoutwe'rejustreallyleakyanimals.Wejust,weleaveourbacteriaeverywherewego."Including,ofcourse,ourphones.Meadowandhiscolleaguestookacensusofthebacteriaonthumbsandindexfingersof17volunteers—andontheirsmartphonetouchscreens.Overall,theyID’edover7,000types.Lookingatjustthemostcommonbacteria,thosethatappearmorethan0.1percentofthetime,theyfoundan82percentsimilaritybetweenthemicrobiomesoffingersandphones.Meaningourphonesareaprettygoodmirrorofourselves,microbially,atleast.TheresultsappearinthejournalPeerJ.[JamesF.Meadow,AdamE.AltrichterandJessicaL.Green,Mobilephonescarrythepersonalmicrobiomeoftheirowners]"Wehavealwaysbeencoveredinbacteria…andwewillalwaysbecoveredinbacteria."Sothefactthatourphonesarealsocoveredinbacteriaisnoreasonforconcern.Infact,theresearcherssaythatmobilephonesmayholduntappedpotentialaspersonalmicrobiomesensors.Appdevelopers,takenote.—ChristopherIntagliata8.MalarialMiceSmellBettertoMosquitoesMiceinfectedwiththeparasitesthatcausetheirtypeofmalariaproduceodorouscompoundsthatattractmosquitoes,increasingtheoddsthattheparasiteswillbespreadtothenextvictimsGettingmalariastinks.Literally.Accordingtoanewstudy,malariavictimsgiveoffodorsthatattractsmosquitoes.Andtheinsectsthatfeedontheinfectedsuffererarethenmorelikelytospreadthedisease.TheworkappearsintheProceedingsoftheNationalAcademyofSciences.[ConsueloM.DeMoraesetal,Malaria-inducedchangesinhostodorsenhancemosquitoattraction]Malariaiscausedbyplasmodiumparasites,whicharetransmittedbymosquitoes.Adecadeago,scientistsfoundthatKenyankidsinfectedwithplasmodiumweremoreattractivetomosquitosthanwerekidswhowereparasite-free.Buttheydidnotknowwhatdrewthebloodsuckerstotheunfortunateinfectedchildren.Tofindout,researcherstookmicethatharboredtherodentversionofmalariaandputtheanimalsinawindchamber.Andtheyfoundthatmosquitosflockedtowardtheinfectedanimals,attractedbytheirsmellalone.Bychemicallyanalyzingtheanimals’scents,theresearchersfoundthattheparasitesboostthelevelsofavarietyofodorouscompoundsthatattractmosquitoes.Soplasmodiumismanipulatingbothitsvictimanditscarriertogetitselfspreadfarandwide.Thefindingmayhelpwithmalariaprevention:ifwecanmaskorharnesstheeaud’infection,maybewecouldnosethemosquitoesawayfrompeople.—KarenHopkin9.ProfessorsStillViewMOOCsSkepticallyAsurveyofprofessorsfindsthatmostseeonlinecoursesasinferiortoin-classlessons--butthosewhohavetaughtonlinearemoreopentotheirpotential.LarryGreenemeierreports.TheNewYorkTimescalls2013“theyearoftheMOOC.”Butmassiveopenonlinecoursesstillfailtogethighmarksfrommosteducators.Inarecentsurveyofmorethan2,200professors,onlyoneinfivethoughtthatonlinecoursescouldbeaseffectiveasclassroomcurricula.Theirbiggestconcern:limitedinteractionbetweenteachersandstudents.ThesurveywasdonebyGallupandthewebsiteInsideHigherEd.RespondentslinkedMOOCcredibilitytowhetheranonlinecoursewasofferedbyanaccreditedschoolandtoastudent’sabilitytoreceivecredits.Facultyskepticismisn’tsurprising.Newtechnologiesoftenturncraftedproductsandservicesintoblandcommodities,somethingnoteacherwants.Ontheotherhand,resistancetochange,especiallywhenitinvolvescomputers,tendstobealosingstrategyinmostfields.Animportantwrinkleinthedata:muchMOOCcriticismcomesfromfacultywho’venevertaughtanonlin