简介：<正>ChinaDailyreportedthatgovernmentministriesaresteppingupthepaceofworkingoutdetailsofthe"BroadbandChina"project,whichis

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简介：Theexplosivegrowthofthebioinformaticsfieldhasledtoalargeamountofdataandsoftwareapplicationspubliclyavailableaswebresources.However,thelackofpersistenceofwebreferencesisabarriertoacomprehensivesharedaccess.Weconductedastudyofthecurrentavailabilityandotherfeaturesofprimarybioinfor-maticswebresources(suchassoftwaretoolsanddatabases).Themajority(95%)oftheexaminedbioinformaticswebresourceswerefoundrunningonUNIX/Linuxoperatingsystems,andthemostwidelyusedwebserverwasfoundtobeApache(orApache-relatedproducts).Oftheoverall1,130UniformResourceLocators(URLs)examined,91%werehighlyavailable(morethan90%ofthetime),whileonly4%showedlowaccessibility(lessthan50%ofthetime)duringthesurvey.Furthermore,themostcommonURLfailuremodesarepresentedandanalyzed.

简介：Sulfurtransformationin3soilsmaintainedinaclosedincubationsystemanditsavailabilitytoplantswereinvestigatedusingcarrier-free^35S-SO4^2-and^35S-labeledryegrassstraw.Forcarrier-freeNa2^35SO4treatment,78%,70%and64%of^35SappliedwerefoundinCa(H2PO4)2-extractaleSfraction,4%,5%and7%inslowlysolubleinorganicS,11%,15%and18%inC-O-S,5%,7%,and6%inC-bondedS,and5%,7%and6%inunidentifiedorganicS120daysafterincubationinblacksoil,cinnamonsoilandchestnutsoil,respectively.Mostof35Suptakebyplantscamefromextractable35SO4^2-,andlittlefromC-O-^35SandC-bonded^35S,Inthetreatmentwith35S-labeledstraw,51%,46%and36%of35SincorporatedwerefoundinCa(H2PO4)2-extractableSfraction,7%,6%and7%inslowlysolubleinorganicS,13%,15%and18%inC-O-S,8%,8%and6%inC-bondedS,and18%,25%and35%inunidentifiedorganicSattheendofincubationinabove-mentonedthreesoils,respectively.HigheravailabilityofC-O-35S,C-bonded35Sandunidentifiedorganic35Sfrom35S-labeledstrawwasobservedin35S-labeledstrawtreatmentcomparedtocarrier-freeNa2^35SO4treatment.

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简介：Background:Europeanforestsareconsideredacrucialresourceforsupplyingbiomasstoagrowingbio-economyinEurope.ThisstudyaimedtoassessthepotentialavailabilityofforestbiomassfromEuropeanforestsanditsspatialdistribution.Wetriedtoanswerthequestions(i)howisthepotentialforestbiomassavailabilityspatiallydistributedacrossEuropeand(ii)wherearehotspotsofpotentialforestbiomassavailabilitylocated?Methods:Thespatialdistributionofwoodybiomasspotentialswasassessedfor2020forstemwood,residues(branchesandharvestlosses)andstumpsfor39Europeancountries.UsingtheEuropeanForestInformationSCENario(EFISCEN)modelandinternationalforeststatistics,weestimatedthetheoreticalamountofbiomassthatcouldbeavailablebasedonthecurrentandfuturedevelopmentoftheforestage-structure,growingstockandincrementandforestmanagementregimes.Wecombinedtheseestimateswithasetofenvironmental(siteproductivity,soilandwaterprotectionandbiodiversityprotection)andtechnical(recoveryrate,soilbearingcapacity)constraints,whichreducedtheamountofwoodybiomassthatcouldpotentiallybeavailable.Wemappedthepotentialbiomassavailabilityatthelevelofadministrativeunitsandatthe10km×10kmgridleveltogaininsightintothespatialdistributionofthewoodybiomasspotentials.Results:Accordingtoourresults,thetotalavailabilityofforestbiomassrangesbetween357and551Tgdrymatterperyear.ThelargestpotentialsupplyofwoodybiomassperunitoflandcanbefoundinnorthernEurope(southernFinlandandSweden,EstoniaandLatvia),centralEurope(Austria,CzechRepublic,andsouthernGermany),Slovenia,southwestFranceandPortugal.However,largepartsofthesepotentialsarealreadyusedtoproducematerialsandenergy.Thedistributionofbiomasspotentialsthatarecurrentlyunusedonlypartiallycoincideswithregionsthatcurrentlyhavehighlevelsofwoodproduction.Conclusions:Ourstudyshowshowthefo

简介：根流出物，微生物殖民和土壤总数一起形成rhizosheath，微生态系统的遵守的特殊柱体根表面。为了学习rhizosheath怎么影响，玷污结构和滋养的分发，我们在壶和地实验在土壤粒子尺寸和滋养的可获得性上分析了玉米rhizosheath的影响。结果证明有在rhizosheath的土壤粒子的重要尺寸减少。同时，在rhizosheath的土壤矿物质氮在tasseling和玉米的成熟阶段在根围或体积土壤比那显著地高。Fe和Mn的内容也是在rhizosheath改变的差别。Rhizosheath开发，由rhizosheath土壤的干燥重量比率显示了到根，在整个试验性的时期期间相对独立于根开发。玉米rhizosheath的形成贡献了土壤粒子尺寸和滋养的可获得性的调整。物理的土壤和化学性质的微妙的本地变化可以在植物进化和驯服的长历史上在土壤形成，rhizospheric生态系统开始，和矿物质营养素动员上有深刻影响。

简介：Athermostaticincubationexperimentwascarriedouttoestimatetheeffectsoffloodingperiods,stalkapplicationandPadditionofFetransformationandPavailabilityincalcareoussoils.SubmergenceincreasedamorphousFe,especiallyinthecaseofstalkapplication.ThenewlyformedamorphousFewithagreatsurfaceareaplayedanimportantroleinPsorption;andsubmergencealsostimulatedthedissolutionofinorganicP,thusincreasingtheavailabilityofsoilPincalcareoussoils.Meanwhile,apartofsolublePwasabsorbedandfixedagainonthesurfaceofnewlyformedamorphousFe,thusresultinginadecreaseofPavailability.SoilrapidlyavailablePincreasedafter150-dayincubation.ThereexistedsignificantlynegativecorrelationsbetweensoilamorphousFecontentandsoilFe-PandrapidlyavailablePcontents.SubmergedconditionspromotedthetransformationofinorganicPaddedtowardFe-Pincalcareoussoils,especiallyinthecaseofstalkapplication.

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简介：IntheexistingliteratureofRepairableQueueingSystems(RQS),i.e.,queueingsystemswithserverbreakdowns,itisalmostallassumedthatinterarrivaltimesofsuccessivecustomersareindependent,identicallyexponentiallydistributed.Inthispaper,wedealwithmoregenericsystemGI/PH/1withserver'sexponentialuptimeandphase-typerepairtime.Withmatrixanalysistheory,weestablishtheequilibriumconditionandthecharacteristicsofthesystem,derivethetransientandstationaryavailabilitybehaviorofthesystem.

简介：Inapreviousgreenhouseexperiment,weshowedthattherewasaninteractionbetweencuandZn,whichaffectedgrowthandmetaluptakebyyoungbarleyplantsgrownonsoiltowhichCd,Cu,Pb,andZnhadbeenadded.Wesuggestedthattheunderlyingmechanismwasthecontroloftheamountofplant-availableZnbycompetitiveadsorptionbetweenCuandZn,Inordertotestthishypothesis,theadsorptionofZnalone,andinthepresenceofaddedCd,CuandPb,hasbeenmeasuredusingthesamesoil.Followingadsorption,theextractabilityoftheZninCaCl2solutionwasmeasured.TheadsorptionisothermsshowedthatoftheaddedmetalsonlyCuhadalargeeffectonZnadsorption.TheeffectofCuwastoreduceZnadsoptionandtoincreasetheamountofCaCl2-extractable(i.e.plant-available)Zn,inagreementwiththeconclusionsfromthegreenhouseexperiment.ThemagnitudeoftheeffectofCuonplant-avalilableZnwassimilarinbothexperiments.

简介：Silicon(Si)isknownasabeneficialnutrientinthecultivationofrice,playingakeyroleinphotosynthesisenhancement,lodgingresistanceandtolerancetovariousenvironmentalstress.ThepresentstudyaimedtoexamineavailableSicontentinbothlowlandsoils(n=29)andneighboringuplandsoils(n=21)collectedfromBeninandNigeriaandtoevaluatethevalidityoftheassessmentresultsthroughapotexperiment.Ourresultsrevealedthattheacetate-buffermethodpredictedSiconcentrationinricestrawattheharveststage(R2=0.68,P<0.01)betterthantheanaerobic-incubationmethod(R2=0.31,P>0.05),and76%oftheuplandsand38%ofthelowlandsweredeficient(<50mg/kg)inacetate-buffersolubleSi.ThesefindingssuggestthattheSi-deficiencysoilsprevailacrossthestudyarea,makingriceplantsstarvedforSiandpronetoenvironmentalstress.

简介：在中国的黄土高原上，干燥土壤层可以由于过量蒸发形成，导致蝗虫(Robiniapseudoacacia)承受的黑色的降级。为了更好设法，预测包含黑蝗虫，这研究被打算调查黑蝗虫蒸发率的反应玷污在黄土高原上用二代表性的土壤(卢拇的泥土和沙的沃土)由气象学的因素影响了的水可获得性。四个土壤水内容为在开始户外的壶然后在一个控制气候的房间种的黑蝗虫幼苗被维持，由弄干或灌溉壶。在两环境，每日的蒸发率被力量功能与空气温度并且由逻辑功能有关引用土壤水分蒸发蒸腾损失总量(et0)。蒸发率比在卢拇的黏土更产生处于在沙的沃土的气象学的条件的变化。在浇得好的处理的蒸发率为比在卢拇的黏土在沙的沃土种的黑蝗虫是更大的。规范的蒸发率由et0是未受影响的直到土壤水内容的批评价值(c)被达到；c价值为卢拇的黏土显著地减少了，但是当et0增加了时，为沙的沃土土壤显著地增加了。这些建议黑蝗虫的蒸发特征上的气象学的条件的效果依赖于土壤质地。

简介：N利用和氨基酸的生合成上的碳(C)和氮(N)来源的效果在arbuscularmycorrhizal(AM)的发芽孢子被检验在到各种各样的N底层，CO2，葡萄糖，或根流出物的暴露以后的真菌血管球intraradicesSchenck与史密斯。N举起和氨基酸的denovo生合成用与集体度谱的察觉的稳定的同位素的标记被分析。高效的液体基于层析的分析被用来测量氨基酸层次。当外长的N来源不在时并且面对25mLL1CO2，发芽AM真菌的孢子利用了从存储类脂化合物的降级导出到biosynthesize的内部N存储以及C骨骼免费氨基酸，丝氨酸和glycine主要在被生产。内部氨基酸的集中作为时间从0～1或2个星期增加了的萌芽逐渐地增加了。然而，天门冬素和夫酸安衰退了到底层；两个降级了向另外的氨基酸的生合成提供C和N施主。外长的无机的N(铵和硝酸盐)和到用仅仅为萌芽的CO2的AM真菌的孢子的器官的N(脲，精氨酸，和夫酸安)的可获得性当外长的N不在时比那些产生了更内部的免费氨基酸超过5次。没有外长的N，到有仅仅CO2的AM真菌的孢子的外长的硝酸盐的供应比那产生了更多的天门冬素超过10次。相反，到AM真菌的孢子的外长的葡萄糖的额外的供应更在外长的N来源的举起产生了重要改进，与超过3次免费氨基酸比与仅仅外长的CO2供应的那些正在被生产。同时，精氨酸是生产的最丰富的免费氨基酸，用作N存储混合物被合并到AM真菌的孢子的蛋白质。

简介：smeltersinNorthernFrancewerestudiedbyanalysingthechemicalformsofthesemetalsandevaluatingtheirphytoavailability.Thesemetalsweredeterminedusingflameorelectrothermalabsorptionatomicspectrometry(FAASorETAAS),dependingontheirconcentrationlevels.AfteroptimisationoftheETAASmethod,characteristicmassofIninwaterandaquaregiawere9.9and18pg,respectively,showingthehighsensitivityoftheanalyticalSoilcontaminationbymetalsfromanthropogenicactivities(e.g.,miningandsmelting)isamajorconcernfortheenvironmentandhumanhealth.Environmentalavailabilityofcadmium(Cd),lead(Pb),zinc(Zn),copper(Cu),andindium(In)in27urbansoilslocatedaroundtwoformerPbandZnsmeltersinNorthernFrancewerestudiedbyanalysingthechemicalformsofthesemetalsandevaluatingtheirphytoavailability.Thesemetalsweredeterminedusingflameorelectrothermalabsorptionatomicspectrometry(FAASorETAAS),dependingontheirconcentrationlevels.AfteroptimisationoftheETAASmethod,characteristicmassofIninwaterandaquaregiawere9.9and18pg,respectively,showingthehighsensitivityoftheanalyticalprocedure.Metalpartitioningwasconductedusingafour-stepsequentialextractionprocedure.TheresultsshowedthatCdandZnweremainlyintheacid-extractableandreducibleformsintheurbansoilsstudied.Incontrast,PbandInwerelargelyinthereduciblefraction.However,insomesamples,theamountofInextractedintheresidualorexchangeablefractionwashigherthanthatinthereduciblefraction.Copperwasmainlyfoundinthereducibleandresidualfractions.Apotexperimentwasconductedinaglasshousewithsevensoils(sixcontaminatedandoneuncontaminated)andtwoplantspecies,ryegrassandlettuce.Theresultsshowedtransferofmetalsfromthecontaminatedsoilstotheshootsofryegrassandtheediblepartoflettuce.ThemetalbioconcentrationfactorwasintheorderofCdCu>In>ZnPbforlettuceleaves,whereas

简介：Mostofthemaintenanceoptimizationmodelsincondition-basedmaintenance(CBM)considerthecost-optimalcriterion,butfewpapershavedealtwithavailabilitymaximizationformaintenanceapplications.AnoveloptimalBayesiancontrolapproachispresentedformaintenancedecisionmaking.Thesystemdeteriorationevolvesasathree-statecontinuoustimehiddensemi-Markovprocess.Consideringtheoptimalmaintenancepolicy,themultivariateBayesiancontrolschemebasedonthehiddensemi-Markovmodel(HSMM)isdeveloped,theobjectiveistomaximizethelong-runexpectedaverageavailabilityperunittime.Theproposedapproachcanoptimizethesamplingintervalandcontrollimitjointly.AcasestudyusingMarkovchainMonteCarlo(MCMC)simulationisprovidedandacomparisonwiththeBayesiancontrolschemebasedonhiddenMarkovmodel(HMM),theage-basedreplacementpolicy,Hotelling’sT2,multivariateexponentiallyweihtedmovingaverage(MEWMA)andmultivariatecumulativesum(MCUSUM)controlchartsisgiven,whichillustratestheeffectivenessoftheproposedmethod.

简介：Afieldtestwiththetraditionalrotationofpaddyrice/uplandcrop(wheat)wascarriedoutonapaddysoilderivedfromredearthtoelucidatetheeffectoforganicmanureonthephoshporusadsorption-desorptionbysoilanditsPavailability.Soilsamplesweretakenfromdifferenttreatmentsatricehavestingstageandanalysed.TheisothermaladsorptionofPbythesamplesfittedverywellwithLangmuirequation,andhence,theparametersintheequation,i.e.,maximumadsorption(qm),constantrelatedtobondingenergy(k)andtheirproduct(k×qm)couldbeusedasacomprehensiveindextocharacterizethepotentialPadsorptivityofthesoil.Organo-inorganicfertilizationandorganicmanuringcoulddecreaseqmandk,whilemineralPapplicationhadlittleeffectonthem.TheisothermaldesorptionofPwassignificantlycorrelatedwithinitiallyaddedandisothermallyadsorbedP.PartofPaddedwasfixed,whichrepresentedthePfixationcapactyofsoil,andorganicmanuringcouldobviouslylowerthePfixation,ThecontentofsoilavailablePhadasignificantnegativecorrelationwithqm,kandfixedP.ItisconcluedthatorganicmanurecouldincreasethePavailabilityofpaddysoilderviedfromredearthbydecreasingqm.k,maximumbufferingcapacity(MBC=k×qm)andfixationcapacity.

简介：Thecalcareousfluvo-aquicsoilwascollectedandamicrocosmstudywascarriedoutwithroot-matandfrozenslicingmethodinlaboratory.ThepHintheroot-soilinterfacewiththecontroltreatmentwasjustslightlylowerthaninthebulksoil.However,theadditionofNH4--NsignificantlydecreasedthepHvalueintheroot-soilinterfaceandtheadditionofNo3-NslightlyincreasedthepHvalueintheroot-soilinterface.ThemagnitudeofpHchangesintheroot-soilinterfacedependedupontheconcentrationsofthenitrogensourcesadded.ThecontentsofCa2-P,Fe-PandAl-Pintheroot-soilinterfaceweremuchloweraftertreatedwithNH4-NandslightlyhigheraftertreatedwithNo3-Ncomparedwithcontroltreatment.Aftertreatedwith100,200and400mg·kg-1NH4+-N,thedeficiencyratesofCa2-Pinthearea0-1mmfromtherootplanewere37.1%,45.9%and57.7%,respectively,thedeficiencyratesofFe-Pwere23.4%,29.1%and38.2%,respectively,andthedeficiencyratesofAl-Pwere25.1%,28.0%and33.2%,respectively.ComparedwiththecontrolthedeficiencyratesofCa8-PinNH4+-NandNo3-Ntreatmentsdecreasedandincreased,respectively,butthedifferenceswerenotobvious.ThecontentsofCa10-PandO-Pintheroot-soilinterfacedidnotsignificantlychangeaftertreatedwithNH4+-NorNo3-N,suggestingthatCa10-PandO-PwereremarkablydifficulttobemobilizedevenatthepresenceofhighconcentrationofNH4+-N.TheloweredpHintheroot-soilinterfaceinducedbytheadditionoftheNH4-Npromotedthetransformationofphosphatesintheroot-soilinterface,enhancedthemobilizationandbioavailabilityofphosphates,andtherebyremarkablyincreasedtheabsorptionofphosphorusbyroots.

简介：Soiltestforavailabilityofnutrientsandheavymetalsisextensivelyservedasameansfortheevaluationsofsoilfertility,andenvironmentaleffectsandphytotoxicityofpollutantsinsoils,andforthefertilizerrecommendationinagriculturalandenvironmentalsciences.Therefore,greatattentionhasbeenpaidtothemeasurementofelementalavailabilityinsoiltest.

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