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一、实验室培养鉴别微生物Millionsofmicrobialspeciespopulatetheworld,butsofaronlyafewhavebeenidentifiedduetotheinabilityofmostmicrobestogrowinthelaboratory.EdgarGoluch,anengineer,andSlavaEpstein,abiologist,aimtochangethis.Thepair,bothresearchersatNortheasternUniversity,hasdevelopedadevicethatallowsscientiststocultivateasinglespeciesofbacteriathatcanthenbestudiedandidentified.Goluch'spreviousresearchdevicesincorporatedpermeable（有渗透性的）membranes1thatallowsequestered2bacteriatobeexposedtothenutrients3andmolecules4oftheirnativeenvironment.Butnaturalcompetitionbetweenspecies,eveninthewild,hassofarlimitedthenumberofspeciesofbacteriathatbiologistshavebeenabletoisolate5withthesemethodsandintraditionallabsettings.GoluchandEpstein'sdevice,detailed6inapaperreleasedJuly1inthejournalPLOSONE,solvesthisproblem.Thisnewdevicepermitsjustasinglebacterial7celltoenteraninnerchamber8containingafoodsource,towhichtheonlyaccessisamicroscopic9passagewayjustslightlynarrowerthanasinglecell.Thepassagewayissosmallthatthefirstcelltoenteritgetsstuck,blockingentrybyanyothercellorspecies.Onceinside,thiscellpro-liferatesasinpreviousdevices,andwhenitdoesitfillsuptheinnerchamberwithapure,single-speciessample,sinceitisisolated10fromcompetitionfromotherspecies.Inthepaper,theteamdemonstratesthedevice'sabilitytoseparatemixturesofcelltypesinalaboratorysetting.Inoneexperiment,theresearchersseparatedtwodifferentbacterialspecieswhosecellsareslightlydifferentsizes--E.coliandP.aueruginosa.Inasecondexperiment,theyisolatedacombinationofsimilarlysizedbutdifferentlyshapedspeciesthatcommonlyshowuptogetherinthemarine11environment--Roseobactersp.andPscyhoserpenssp.Finally,theyusedthedevicetoseparatecellsofthesamespeciesthathadbeendifferentiallytaggedtogloweitherredorgreen.Thisfinalexperimentvalidates12thehypothesisthatthecellsgrowninsidethefoodchamberaredaughtersofthesinglecellcaughtintheentryway.EpsteinwilltestthedevicesinthebiologicalsettingbeginningthismonthduringaresearchtriptoGreenland.Goingforward,fundingfromanInstrumentDevelopmentBiologicalResearchGrantfromtheNationalScienceFoundationwillenableGoluchandhisteamofengineerstobeginoptimizing13thedeviceanditsmanufactureonalargerscale.1membranesn.（动物或植物体内的）薄膜(membrane的名词复数)；隔膜；（可起防水、防风等作用的）膜状物参考例句：Thewastematerialisplacedincellswithpermeablemembranes.废液置于有渗透膜的槽中。Thesarcoplasmicreticulumisasystemofintracellularmembranes.肌浆网属于细胞内膜系统。2sequesteredadj.扣押的；隐退的；幽静的；偏僻的v.使隔绝，使隔离(sequester的过去式和过去分词)；扣押参考例句：Thejuryisexpectedtobesequesteredforatleasttwomonths.陪审团渴望被隔离至少两个月。Everythingheownedwassequestered.他的一切都被扣押了。3nutrientsn.（食品或化学品）营养物，营养品(nutrient的名词复数)参考例句：alackofessentialnutrients基本营养的缺乏Nutrientsareabsorbedintothebloodstream.营养素被吸收进血液。来自《简明英汉词典》4molecules分子(molecule的名词复数)参考例句：Thestructureofmoleculescanbeseenunderanelectronmicroscope.分子的结构可在电子显微镜下观察到。Insidethereactorthelargemoleculesarecrackedintosmallermolecules.在反应堆里，大分子裂变为小分子。5isolatevt.使孤立，隔离参考例句：Donotisolateyourselffromothers.不要把自己孤立起来。Weshouldneverisolateourselvesfromthemasses.我们永远不能脱离群众。6detailedadj.详细的，详尽的，极注意细节的，完全的参考例句：Hehadmadeadetailedstudyoftheterrain.他对地形作了缜密的研究。Adetailedlistofourpublicationsisavailableonrequest.我们的出版物有一份详细的目录备索。8chambern.房间，寝室；会议厅；议院；会所参考例句：Formany,thedentist'ssurgeryremainsatorturechamber.对许多人来说，牙医的治疗室一直是间受刑室。Thechamberwasablazewithlight.会议厅里灯火辉煌。9microscopicadj.微小的，细微的，极小的，显微的参考例句：It'simpossibletoreadhismicroscopichandwriting.不可能看清他那极小的书写字迹。Aplant'slungsarethemicroscopicporesinitsleaves.植物的肺就是其叶片上微细的气孔。10isolatedadj.与世隔绝的参考例句：Hisbadbehaviourwasjustanisolatedincident.他的不良行为只是个别事件。Patientswiththediseaseshouldbeisolated.这种病的患者应予以隔离。12validatesv.证实(validate的第三人称单数)；确证；使生效；使有法律效力参考例句：Otherresearchvalidatesthatwhenitcomestochocolate,typedoesmatter.其他的研究也证实了不同种类的巧克力确实功效不同。Troubleshootsequipment,reviewandvalidatesdataandcompletereports.管理错误描述设备，审查并确认试验数据，完成试验报告。13optimizingv.使最优化，使尽可能有效(optimize的现在分词)；最佳化；寻优参考例句：Thismodelmaybeclassifiedaseitheranoptimizingmodelorsimulationmodel.这个模型可分为最佳化模型或模拟模型。NeedtodesigncrossoveroperatorrationallywhileoptimizingANN.优化网络需要合理设计交叉算子。二、海洋微生物具有独立的日常代谢系统Imaginetheopenoceanasamicrobialmegacity（大城市）,teeming1with（富于，充满）lifetoosmalltobeseen.Ineverydropofwater,hundredsoftypesofbacteriacanbefound.Nowscientistshavediscoveredthatcommunitiesoftheseoceanmicrobeshavetheirowndailycycles--notunliketheresidentsofabustling2citywhotendtowakeup,commute3,work,andeatatthesametimes.What'smore,it'snotallaboutthesun.Light-lovingphotoautotrophs（光合自养生物）--bacteriathatneedsolarenergytohelpthemphotosynthesizefoodfrominorganic4substances--havebeenknowntosunthemselvesonaregularschedule.ButinanewstudypublishedintheJuly11issueofthejournalScience,researchersworkingatStationALOHA,adeepoceanstudysite100kmnorthofOahu,observeddifferentspeciesoffree-living,heterotrophicbacteriaturningondiel（一昼夜的）cyclinggenes6atslightlydifferenttimes--suggestingawaveoftranscriptionalactivitythatpassesthroughthemicrobialcommunityeachday.Iliketosaytheyaresinginginharmony,saidEdwardF.DeLong,professorofOceanographyatUniversityofHawaiiatManoaandtheheadoftheMassachusettsInstituteofTe