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简介：Humankinddrawsimportantbenefitsfromlarge-scaleecologicalprocessestermedecosystemservices,yetthestatusofseveralofthemisdeclining.Reliablemonitoringmethodsareessentialfortrackingthestatusofecosystemservices.Predationisthemainstayofnaturalpestcontrol,akeyecosystemservice.Weusedgreenplasticinecaterpillarstomonitorpredationpressure,andtoobtainbaselinedataonpredatoractivityintransgenicBtversusnon-BtmaizefieldsinOldandNewWorldcountries.Predationpressurewasmeasuredatgroundandcanopylevelsusinganidentical,small-plotexperimentaldesigninfourEuropeancountries(Denmark,Slovakia,RomaniaandItaly)andArgentina.Totalpredationrateinmaizewasll.7%d^-1(min.7.2%d^-1inArgentina,max.29.0%d^-1inRomania).Artificialcaterpillarswereattackedbothbyinvertebrates(mostlychewinginsectswith42.0%oftheattackmarks,andantswith7.1%,butalsopredatoryandparasitoidwasps,spidersandslugs),andvertebrates(smallmammals25.5%,andbirds20.2%).Totalpredationatgroundlevel(15.7%d^-1)wassignificantlyhigherthaninmaizecanopies(6.0%d^-1)inallcountries,exceptArgentina.WefoundnosignificantdifferencesbetweenpredatorpressureinBtversusnon-Btmaizeplots.Theartificialcaterpillarmethodprovidedcomparable,quantitativedataonpredationintensity,andprovedtobesuitableformonitoringnaturalpestcontrol.Thismethodusefullyexpandstheexistingtoolkitbydirectlymeasuringecologicalfunctionratherthanstructure.

简介：Withtheexceptionofmatureerythrocytes,cellswithinthehumanhematopoieticsystemarecharacterizedbythecellsurfaceexpressionofthepan-leukocytereceptorCD45.Here,weidentifyanovelsubsetamongmononuclearcordbloodcellsdepletedoflineagecommitmentmarkers(Lin-)thataredevoidofCD45expression.Surprisingly,functionalexaminationofLin-CD45-cellsalsolackingcellsurfaceCD34revealedtheywerecapableofmultipotentialhematopoieticprogenitorcapacity.Co-culturewithmouseembryoniclimbbudcellsdemonstratedthatLin-CD45-CD34-cellswerecapableofcontributingtocartilagenodulesanddifferentiatingintohumanchondrocytes.BMP-4,amesodermalfactorknowntopromotechondrogenesis,significantlyaugmentedLin-CD45-CD34-differentiationintochondrocytes.Moreover,unlikeCD34+humanhematopoieticstemcells,Lin-CD45-CD34-cellswereunabletoproliferateorsurviveinliquidcultures,whereassingleLin-CD45-CD34-cellswereabletochimerizetheinnercellmass(ICM)ofmurineblastocystsandproliferateinthisembryonicenvironment.OurstudyidentifiesanovelpopulationofLin-CD45-CD34-cellscapableofcommitmentintobothhematopoieticandchondrocyticlineages,suggestingthathumancordbloodmayprovideamoreubiquitoussourceoftissuewithbroaderdevelopmentalpotentialthanpreviouslyappreciated.

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简介：Wepresentarapidsystemforpredictingbeeftendernessbymimickingthehumantactilesense.ThedetectionsystemincludesaFSpressuresensor,apowersupplyconversioncircuit,asignalamplifierandaboxinwhichthesampleismounted.AsampleofrawLongissimusdorsi(LD)muscleisplacedinthemeasuringbox;thenarodconnectedtothepressuresensorispressedintothebeefsampletoagivendepth;thereactionforceofthebeefsampleismeasuredandusedtopredictthetenderness.SensoryevaluationandWarner-BratzlerShearForce(WBSF)evaluationofsamplesfromthesameLDmuscleareusedforcomparison.Thenewdetectionsystemagreeswithestablishedprocedure95%ofthetime,andthetimetotestasampleislessthan5minutes.

简介：Thesurfaceglycoproteinhemagglutinin(HA)helpstheinfluenzaAvirustoevadethehostimmunesystembyantigenicvariationandisamajordrivingforceforviralevolution.Inthisstudy,theselectionpressureonHAofH5N1influenzaAviruswasanalyzedusingbioinformaticsalgorithms.Mostoftheidentifiedpositiveselection(PS)siteswerefoundtobewithinoradjacenttoepitopesites.SomeoftheidentifiedPSsitesareconsistentwithpreviousexperimentalstudies,providingfurthersupporttothebiologicalsignificanceofourfindings.ThehighestfrequencyofPSsiteswasobservedinrecentstrainsisolatedduring2005–2007.PhylogeneticanalysiswasalsoconductedonHAsequencesfromvarioushosts.Viraldriftisalmostsimilarinbothavianandhumanspecieswithaprogressivetrendovertheyears.OurstudyreportsnewmutationsinfunctionalregionsofHAthatmightprovidemarkersforvaccinedesignorcanbeusedtopredictisolatesofpandemicpotential.

简介：Thenumberofcompletelysequencedarchaealgenomeshasbeensufficientforalarge-scalebioinformaticstudy.Wehaveconductedanalysesforeachcodingregionfrom36archaealgenomesusingtheoriginalCGSalgorithmbycalculatingthetotalGCcontent(G+C),GCcontentinfirst,secondandthirdcodonpositionsaswellasinfourfoldandtwofolddegeneratedsitesfromthirdcodonpositions,levelsofargininecodonusage(Arg2:AGA/G;Arg4:CGX),levelsofaminoacidusageandtheentropyofaminoacidcontentdistribution.InarchaealgenomeswithstrongGCpressure,arginineiscodedpreferablybyGC-richArg4codons,whereasinmostofarchaealgenomeswithG+C<0.6,arginineiscodedpreferablybyAT-richArg2codons.InthegenomeofHaloquadratumwalsbyi,whichiscloselyrelatedtoGC-richarchaea,GCcontenthasdecreasedmostlyinthirdcodonpositions,whileArg4>>Arg2biasstillpersists.Proteomesofarchaealspeciescarrycharacteristicaminoacidbiases:levelsofisoleucineandlysineareelevated,whilelevelsofalanine,histidine,glutamineandcytosinearerelativelydecreased.NumerousgenomicandproteomicbiasesobservedcanbeexplainedbythehypothesisofpreviouslyexistedstrongmutationalATpressureinthecommonpredecessorofallarchaea.

简介：Humanplacenta-derivedmononuclearcells(MNC)wereisolatedbyaPercolldensitygradientandculturedinmesenchymalstemcell(MSC)maintenancemedium.Thehomogenouslayerofadherentcellsexhibitedatypicalfibroblastlikemorphology,alargeexpansivepotential,andcellcyclecharacteristicsincludingasubsetofquiescentcells.Invitrodifferentiationassaysshowedthetripotentialdifferentiationcapacityofthesecellstowardadipogenic,osteogenicandchondrogeniclineages.FlowcytometryanalysesandimmunocytochemistrystainshowedthatplacentalMSCwasahomogeneouscellpopulationdevoidofhematopoieticcells,whichuniformlyexpressedCD29,CD44,CD73,CD105,CD166,laminin,fibronectinandvimentinwhilebeingnegativeforexpressionofCD31,CD34,CD45andα-smoothmuscleactin.Mostimportantly,immuno-phenotypicanalysesdemonstratedthatthesecellsexpressedclassImajorhistocompatibilitycomplex(MHC-Ⅰ),buttheydidnotexpressMHC-Ⅱmolecules.Additionallythesecellscouldsuppressumbilicalcordblood(UCB)lymphocytesproliferationinducedbycellularornonspecificmitogenicstimuli.Thisstronglyimpliesthattheymayhavepotentialapplicationinallografttransplantation.SinceplacentaandUCBarehomogeneous,theMSCderivedfromhumanplacentacanbetransplantedcombinedwithhematopoieticstemcells(HSC)fromUCBtoreducethepotentialgraft-versus-hostdisease(GVHD)inrecipients.

简介：来自哈尔滨医科大学附属第一临床医学院与上海交通大学医学院附属瑞金医学院的2个研究团队在白血病研究方面同时取得新的进展，相关成果文章分别发表在《Blood》和《CancerCell》上。