简介：OPM05-M2100,thespecificRAPDfragmentofBursaphelenchusxylophilus,wascollectedfromagarosegelsandpurified.Then,thepurifiedfragmentwasinsertedintothepGEMR-TVectorthatwastransformedintoEscherichia.coliandclonedandsequenced.BasedonthesequenceofRAPDmarker,thesequencescharacterizedamplifiedregion（SCAR）primersweredesignedbytheaidofthesoftwareOligo5.0.TheforwardprimerisM05F2（5’-CGGGTCATGGCTGGAGGTATCGT-3’）,andthebackwardprimerisM05R1(5’-TGGCTCAATGGCAAATCCTTCGTA-3’.Thespecificfragment(OPM05-M2100)wassuccessfullyconvertedtoSCARmarker(SCAR-M05-X600)byusingM05F2/R1,whichwasthespecificmarkersofB.xylophilus.Then,theDNAof92isolatesofBursaphelenchus,B.mucronatus,B.hofmanni,AphelenchoidesmacronucleatusandSeinurasp.whichwereisolatedfromdeadpines,weremarked,andtheDNAofasinglenematodeextractedwithasimplemethodwasdetectedusingthissetofspecificprimers.TheresultsindicatedthatthePCRproductofall81isolatesofB.xylophiluswasaclearandbrightfragmentabout600bpwithM05F2/R1.ButeightisolatesofB.mucronatus,oneB.hofmanni,oneA.macronucleatusandoneSeinurasp.hadnoanyfragments.AssayM05F2/R1alsosuccessfullydetectedsinglepinewoodnematode.Therefore,thespecificpairwiseswouldbeusedforconstructingidentificationkitsofB.xylophilus,implementingtheaimofquickdetection,andachievingthepurposeofidentifyjuvenilesuccessfully.

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简介：Fungalpathogenscausingpoplarcankerdiseasesarecosmopolitaninspecies,andhaveawiderangeofhosts.Thesepathogenshavediverseanamorphsandtheirmorphologyoverlapswitheachother;Theirteleomorphsarehardlydiscoveredinnature.Furthermore,theidentificationofthesepathogensisusuallylimitedbythegeography,hostandtaxonomicknowledge.Therefore,aculture-independentmethodusedtoidentifydeterminepathogensisexpectedtobedevelopedforfielddiagnostics.Throughamplifying,sequencingandanalyzingmultiplexnucleicacidtemplatesandgeneticmarkedtargetsequences,amultiplexPCRtechniquehasbeenestablishedandusedtodirectlydetectvariousenvironmentalsamples.Inthisstudy,fourpathogenstrainsandenvironmentalsampleswereamplifiedusingfungaluniversalprimersITS1/ITS4andEF1-728F/EF1-986RbygeneralPCRandmultiplexPCR.Theampliconsweresequenced,andthenalignedinGenBank.TheresultshowedthatthemultiplexPCRwasabletosuccessfullyamplifythetargetgeneandidentifythepathogensfromenvironmentalsamplesintheconditionofanannealingtemperatureof55.6℃andprimersfinalconcentrationof0.2μmol·L-1.ThemultiplexPCRcouldamplifythetargetattheconcentrationlevelofapproximatelylngofgenomicDNA.ThismethodwouldprovideausefultoolfortheidentificationofcankerpathogensbythemultiplexPCRandthehigh-throughputDNAmicroarraydetectionofenvironmentalsamples.

简介：Background:Monitoringthechangingpatternofvegetationacrossdiverselandscapesthroughremotesensingisinstrumentalinunderstandingtheinteractionsofhumanactivitiesandtheecologicalenvironment.LandusepatterninthestateofHimachalPradeshintheIndianWesternHimalayashasbeenundergoingrapidmodificationsduetochangingcroppingpatterns,risinganthropogenicpressureonforestsandgovernmentpolicies.WestudiedlandusechangeinSolanForestDivisionofHimachalPradeshtoassessspecieswiseareachangesintheforestsoftheregion.Methods:Thesupervisedclassification(Maximumlikelihood)ontwodatesofIRS(LISSIII)satellitedatawasperformedtoassesslandusechangeovertheperiod1998–2010.Results:Sevenlandusecategorieswereidentifiednamely,chirpine(Pinusroxburghii)forest,broadleavedforest,bamboo(Dendrocalamusstrictus)forest,banoak(Quercusleucotrichophora)forest,khair(Acaciacatechu)forest,culturableblankandcultivation.Theareaunderchirpine,cultivationandkhairforestsincreasedby191ha(4.55%),129ha(13.81%)and77ha(23.40%),whereastheareaunderbanoak,broadleaved,culturableblankandbamboodecreasedby181ha(16.58%),152ha(6.30%),71ha(2.72%)and7ha(0.47%),respectively.Conclusions:Thestudyrevealedadecreaseintheareaunderforestandculturableblankcategoriesandasimultaneousincreaseintheareaundercultivationprimarilyduetothelargescaleintroductionofhorticulturalcashcropsinthestate.Thecompositionofforestsalsoexhibitedsomemajorchanges,withanincreaseintheareaofcommerciallyimportantmonocultureplantationspeciessuchaspineandkhair,andadeclineintheareaofoak,broadleavedandbamboowhicharefacingahighanthropogenicpressureinmeetingthelivelihooddemandsofforestdependentcommunities.Intimedeforestation,forestdegradationandecologicalimbalancesduetothechangingforestspeciescompositionmayinflictirreversibledamagesuponunstableandfragilemountainzonessuchastheIndianH

简介：Visualclassificationandstresswavenon-destructivetestingtechnologywereadoptedtoevaluatethedecaystatusofancientPopuluswoodmembers(rafters)replacedfromthePotalaPalace.Thedecaystatusofwoodmemberswasevaluatedbystresswavetestingandvisualobservation.Formostoftheancientwoodmembers,theevaluationresultsbytwomethodswereconsistentwitheachother.Alsostresswavetestingtechniquescanfindtheinternalwoodmemberdecaytoeliminatethehiddenhazardforancientwoodmembers,andofferrelativelyaccuratequantitativeinformationforthesafetystatusofancientwoodmembers.Thusduringthemaintainingforancientarchitectures,visualobservationcombinedwithstresswavetestingtechniquesisagoodwaytoevaluatethedegradationofancientwoodmembers.

简介：Thelocaldamagessuchasknots,decay,andcrackscanbetranslatedintoareductionofservicelifeduetomechanicalandenvironmentalloadings.Inwoodconstruction,itisveryimportanttoevaluatetheweakestlocationanddetectdamageattheearliestpossiblestagetoavoidthefuturecatastrophicfailure.Inthisstudy,themodaltestingwasoperatedonwoodbeamstogeneratethefirsttwomodeshapes.Anovelstatisticalalgorithmwasproposedtoextractthedamageindicatorbycomputingthemodalflexibilitycurvaturebeforeandafterdamageintimbers.Thedifferentdamageseverities,damagelocations,anddamagecountsweresimulatedbyremovingmassfromintactbeamstoverifythealgorithm.Theresultsshowedthattheproposedstatisticalalgorithmwaseffectiveandsuitabletothedesigneddamagescenarios.Itwasreliabletodetectandlocatelocaldamagesunderdifferentseverities,locations,andcounts.Thepeakvaluesofthedamageindicatorscomputedfromthefirsttwomodeshapesweresensitivetodifferentdamageseveritiesandlocations.Theywerealsoreliabletodetectthemultipledamages.