简介：为快速鉴别白灵菇种质资源的真伪,对58个供试菌株进行ITS特异性扩增,根据遗传差异选择菌株进行ITS克隆测序,经ITS-RFLP分析和ITS序列分析得知：58个供试菌株中,Pl.n0010、Pl.n0020、Pl.n0025、Pl.n0041这4个菌株为杏鲍菇;菌株Pl.n0037是糙皮侧耳;余下53个菌株为白灵菇。结果表明：ITS-RFLP可应用于白灵菇与杏鲍菇菌株间的鉴定。

简介：JustasFranceandGermanytookanincreasinglydivergentstandwiththeUnitedStatesovertheIraqissue,onJanuary3rd,2003,eightcountriesincludingBritain,Italy,Spain,Portugal,Denmark,Poland,CzechRepublicandHungarymadeajointstatementintheBritishTimes,appealingtoEuropetoactinconcertwithU.S.overtheissueofusingforceagainstIraq.Thisstatementhaditthatitwas

简介：Letl1,l2,…,lgbeevenintegersandxbeasufficientlylargenumber.Inthispaper,theauthorsprovethatthenumberofpositiveoddintegersk≤xsuchthat（k+l1）2,（k+l2）2,…,（k+lg）2cannotbeexpressedas2n+pαisatleastc（g）x,wherepisanoddprimeandtheconstantc（g）dependsonlyong.

简介：Japan'sdiplomacyrelatedtotheUnitedNationscanbetracedbackto1956whenitformallyjoinedtheUnitedNations.Afterraisingthegoalofbecominga'politicalpower'inthe1980s,Japan,inordertoboostitsinternationalstatus,hassparedno

简介：TheemergenceofZhangHeng’sseismoscopehasaprofoundhistoricalbackground.ThispaperintendstoexploretheformationandmaterialbasisofZhangHeng’sscientificthought.Itappearsthatthesimpleintentionof"observingvisionsanddistinguishinggoodfortuneormisfortune"washismotivationtodeveloptheseismoscope.Tracingitshistoricalbackground,theauthorsproposedinthispaperthatthedevelopmentofthisseismoscopestartedaround128A.D.,andbasedonperceptualknowledge,twoideasaboutearthquakescameintobeing,i.e.,earthquakelocationcouldbejudgedaccordingtotheinstrumentshakingdirection,andtheearthquakeandearthsplitwereessentiallydifferent.Intheinstrumentmanufacture,ZhangHengadvocatedaprincipleof"makingutensilstoimitatecosmos".Bythisprinciple,thefollowingthreeproblemswerereadilysolved:theseismoscopeimitatedtheresponseofthesuspensionsystemtoearthquakes(i.e.naturalseismoscope).Technically,thetriggermechanismofthelatchwasusedforreference,anditrecordedthephysicalevidenceofearthquakeoccurrencebyaningeniouswayofaballdroppingfromadragon’smouth.Thesolutionofthesethreekeyproblemsleadtotheemergenceoftheseismoscopein132A.D.andthesuccessfuldetectionofanearthquakein134A.D.Hisinventiondeepenedhumanity’sknowledgeofnaturallaws,andpromotedthedevelopmentofscienceandtechnologyinthattimeandlater.

简介：TheheightoftheU.S.strengthisattheperiodfromPresidentClinton'scomingtopowerin1992tilltheendofthelarge-scalebattlesintheIraqwaronMay1,2003.HowAmerica'snationalfortunewilldevelopdependsonhowAmericawillresolvetheIraqissue,implementitsprogramofreformingMiddleEast,andmaintaininsteadofdamagingitsnationalfundamentalprinciplesathome.

简介：WiththearchitecturalhistoryupontheQinghai-TibetPlateauspanningbackfourtofivethousandyears,theTibetanarchitecturehasgivenrisetothreebasicforms:palaces,monasteriesandcivilianresidences.

简介：Trump'sMiddleEastpolicycouldbesummarizedas"oneaxisandthreeapproaches."ThemaindriveriscreatinganallianceofIsraelandSaudiArabia,andhisthreeapproachesaretocontainIran,counterterrorism,andlaunchthedealofthecentury.BehindthisMiddleEastpolicyisTrump'saccelerationofglobalcontraction,andareturntotheUSpro-Israeldiplomatictradition,bothinfluencedbyTrumpianstyleandtheJewishpeoplearoundhim.AnyrelianceonanIsrael-SaudiArabiaallianceisinherentlyfragile,thepotentialforIranregimechangeunclear,andTrump'splanneddealwoulddestabilizetheregionandexpandaUS-Europeanrift.ChangingthisdirectionwouldrequiretheUStothinkmoredeeplyaboutMiddleEastlong-termprospectstofindamorebalancedpolicy.

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简介：为了解烟草内生细菌的多样性,采用改良的NA培养基和稀释平板法从不同生长期的烟草的根、茎、叶中分离得到127株内生细菌。利用细菌16SrDNA特异引物扩增得到16SrDNA的部分片段,长约700bp,分别用内切酶MspⅠ、HaeⅢ、AfaⅠ、HinfⅠ对扩增产物进行限制性酶切。16SrDNAPCR-RFLP分析中,在100%相似性水平处,除了cj23、ty16、cg23、wy6、cj25、wy13、my23、ty7、cj14、cg25、cg2、cj13、my11,my27单独成群外,其余菌株分为15个分类操作单元,其中Otu1、Otu2,Otu27类群最大,分别包括了27、18,26个菌株。对29个代表菌株16SrDNA序列系统发育分析表明,这些菌株主要分布于芽孢杆菌（Bacillus）分支,其余菌株分布于葡萄球菌属（Staphylococcus）、微杆菌属（Microbacterium）、单胞菌属（Sphingomonas）、中华根瘤菌属（Sinorhizobium）、土壤杆菌属（Agrobac-terium）、根瘤菌属（Rhizobium）、纳西杆菌属（Naxibacter）、贪铜菌属（Cupriavidus）、寡养食单胞菌属（Stenotrophomonas）、不动杆菌属（Acinetobacter）、假单胞菌属（Pseudomonas）、肠杆菌属（Enterobacter）、泛菌属（Pantoea）、克雷伯菌属（Klebsiella）、Bifissio属系统发育分支。通过Shannon多样性指数对不同生长期分离到的菌株进行多样性分析和比较,结果表明团棵期叶片中分离到的内生细菌多样性最大,随后是旺长期,苗期次之,成熟期最小。

简介：ManybelievethatChinaandtheU.S.havebeenstrugglingagainsteachothertogaintheupperhandintheEastAsianregion-andtheareabeyondChina'scoastline-inrecentyears.

简介：Ofitstotalexportvolume,theproportionofChina’snewandhightechnologyproductsandhighvalue-addedproductsisextremelylow.Itspuretechnologicalexportrateisonly2percentofthetotal.Therefore,alongwiththetransformationofthemodeofgrowthofChina’snationaleconomy,acorrespondinggrowthmodetransformationshouldtakeplaceinitsforeigntradesector,anditisnecessarytoachieveasignificantchangeinitsimportandexportproductmix.

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简介：BycombiningChapman-EnskogexpansionwiththeBGKapproximationtoBaltzmannequationandNavier-Stokesequationwasobtained.AndanexpressionofDarcy'slawwasobtainedthroughtakingvariableaverageoverNavier-Stokesequationonsomerepresentativespaceinporousmedia,andfinallyanexamplewastakentoproveitsreliability.

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简介：应用ＣＤＳＮ台网兰州数字台的记录和中法合作建立的朗索数字台的记录，研究了１９９５年７月２２日甘肃永登５．８级地震和１９９６年６月１日天祝－古浪５．４级地震前台剪切波分裂的特征。结果表明，在永登地震前大约１年的时间延迟和偏振方向很快恢复。因此，可以认为，此次地震前ＮＷ向，地震后剪切波分裂时间延迟和偏振方向很快恢复。因此，可以认为，此次地震前Ｓ波分裂方向的前兆特征是明显的。对于天祝－古浪５．４级地震，

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