简介:Themechanismofhealtheffectscausedbyorganohalogenpollutants,e.g.,toxinsfromelectronicwaste(e-waste),ispoorlyunderstood.WesupposedthatmicroRNAs(miRNAs),animportantpost-transcriptionalregulator,couldplayaroleinthisprocess.Inthisstudy,fastingperipheralbloodsampleswerecollectedfromresidentslivingatane-wastesiteinnorthernChinaandanearbyreferencepopulation.Concentrationsofe-wasterelatedorganohalogenpollutantsinplasmafromtheexposuregroupwerehigherthanthecorrespondingmeasurementinthereferencegroup.Correspondingly,sixtymiRNAsinplasmashowed>2-foldchangebetweenthetwogroupsinmicroarrayanalysis.Amongthem,miR-125a-5pwasconfirmedtobeupregulatedbyqRT-PCRanditsvalidatedtargetswereenrichedinresponsestoxenobioticsandcancerrelatedpathways.Furthermore,significantpositivecorrelationswerefoundbetweenlevelsofmiR-125a-5pinplasmaandreactiveoxygenspecies(ROS)inpolymorphonuclearneutrophilleukocytes(P<0.05).Theseevidencessuggestedoxidativestressmightbeanintermediatebetweene-wasterelatedPOPsexposureandalterationofplasmamiRNA.
简介:利用RT-PCR(ReverseTranscriptionPolymeraseChainReaction)分离阿部鲻(Mugilogobiusabei)P-gp(P-glycoproteins)CDS(Sequencecodingforaminoacidsinprotein)基因,并进行序列测定与分析。结果表明,cDNA全长2073bp,其中阅读框1958bp,编码652个氨基酸,估算的蛋白质相对分子质量为71.87kD;5′非翻译区115bp。序列同源性分析表明,不同进化地位动物的P-gp编码序列存在高度同源性,显示P-gp基因在系统进化上高度保守。生物信息学分析表明,阿部鲻P-gp基因不含有编码蛋白信号肽的序列,预测结果显示,有4个跨膜区,编码蛋白含ATP结合盒(theATP-bindingcassette)内膜转运typ-1型结合域。
简介:通过探究iNOS/p38MAPK信号通路在丙烯腈(acrylonitrile,ACN)诱导脑组织损伤中的作用,为进一步研究ACN的神经毒性作用提供依据。选取50只SPF级健康成年雄性SD大鼠,随机分为5组,每组10只。适应性饲养一周后,以12.5、25.0、50.0mg·kg^-1ACN对大鼠进行灌胃染毒,对照组给予玉米油,另设NAC组(300.0mg·kg^-1NAC+50.0mg·kg^-1ACN),1次·天^-1,6天·周^-1,共染毒13周。次日称重并处死大鼠,测定大鼠脑组织NO含量、总NOS水平及iNOS、p-p38和p38蛋白表达水平。结果显示,ACN各剂量组大鼠脑组织脏器系数与对照组比较均显著降低(P〈0.05),高剂量组大鼠脑脏器系数与NAC组比较降低(P〉0.05)。高剂量组NO含量和总NOS水平显著高于对照组,与NAC组比较,高剂量组NO含量降低(P〉0.05),总NOS水平升高(P〉0.05)。Westernblot结果显示,ACN高剂量组大鼠脑组织iNOS、p-p38蛋白表达水平和p-p38/p38比值显著高于对照组和NAC组(P〈0.05)。ACN可激活iNOS/p38MAPK信号通路,这可能是ACN致大鼠脑组织损伤的机制之一。
简介:通过涂覆热分解法制备了Ti/RuO2-ZrO2-SnO2、Ti/RuO2电极材料,采用X射线衍射(XRD)、扫描电镜(SEM)和循环伏安(CV)对电极材料进行表征,考察了电流密度、NaCl质量浓度、pH值及电极间距对废水COD降解率的影响。结果表明,Ti/RuO2-ZrO2-SnO2电极对COD具有更高的降解率,对其进行工艺优化。电极材料对废水降解的最佳工艺条件为电流密度40mA/cm^2,NaCl质量浓度4g/L,pH=5.0,电极间距10mm,COD的降解率达到90.5%。Ti/RuO2-ZrO2-SnO2电极中SnO2与RuO2生成固溶体,有利于增强涂层与基体之间的结合力,提高电极的稳定性;ZrO2起到细化晶粒的作用,致使电极表面粗糙度增加,增强了电极的电催化性能,且降解过程符合一级动力学模型。
简介:2009年的北京国际通信展是3G牌照发放后工业和信息化部主办的首个国际大型信息通信展览会。无线网络优化覆盖领域的领军企业烽火科技,以全新的"烽火,志在网络/智在网络/自在网络"集团
简介:为探讨纳米MnO2与常规MnO2粉末对细胞DNA损伤作用的差别,采用不同浓度的纳米MnO2与常规MnO2粉末(0、100、200、400μg·mL^-1)对Hela细胞进行染毒,应用单细胞凝胶电泳(彗星实验)检测Hela细胞的损伤效应.结果表明,与对照组相比,纳米MnO2和常规MnO2各染毒组细胞尾部DNA百分率(TailDNA%)和尾矩(TailMoment)均显著增加(p〈0.01);同一浓度下,纳米MnO2组细胞尾部DNA百分率和尾矩显著高于常规MnO2组(p〈0.01).以上结果表明,纳米MnO2和常规MnO2粉末均能导致Hela细胞DNA损伤,且纳米MnO2的损伤作用强于常规MnO2.
简介:Globalclimatechangeisoneofthemajorenvironmentalissuesfacedbyhumans.Existingevidenceindicatesthattheanthropogenicpushforariseintheatmosphericconcentrationofgreenhousegases(GHGs)(particularlyCO2)hasbeenaprimarycauseforglobalwarming.Asidefromeconomicandteclinologicalfactors,demographicdynamics(includinghumanconsumptioninabroaddemographicsense)hasbeenamajordriverforCO2emissions.Inthispaper,weperformedbothnonlinearregressionanalysis(basedontheSTIRPATmodel)andgraycorrelationdegreeanalysis(basedongraysystemtheory)ontheimpactofdemographicdynamicsonCO2emissions.OurresultsrevealthatCO2emissionsarepositivelycorrelatedwithpopulationsizeandGDPpercapitaandnegativelycorrelatedwithenergyintensity.WealsoshowthatgraycorrelationdegreewithCO2emissionsforfivevariables(i.e.,householdconsumption,urbanizationrate,householdsize,populationagingrate,populationsize)variessubstantially:householdconsumption>urbanizationrate>householdsize>populationagingrate>populationsize,withhouseholdconsumptionbeingthehighest,andpopulationsizethelowest.TomitigatetheimpactofdemographicdynamicsonCO2emissions,itisofvitalsignificancetonurturepeople’sawarenessofsustainableconsumptionandtoadheretocurrentpopulationcontrolpolicies.
简介:HouseholdconsumptionisoneoftheimportantfactorsthatinduceCO2emission.Basedoninput-outputmodel,thisarticlecalculatedtheintensityofCO2emissionofdifferentincomegroupsandsevenprovincesinChina,andthenestimatedtotalCO2emissioninducedbyurbanhouseholdconsumptionfrom1995to2004inChinabasedonstatisticdataofhouseholdlivingexpenditure.TheresultsshowthatCO2emissionpercapitainducedbyhouseholdconsumptionhadincreasedfrom1583to2498kgCO2during1995-2004.Theratioofconsumption-inducedCO2emissiontototalCO2emissionhadrisenfrom19%to30%inthepastdecade.IndirectCO2emissionaccountedforanimportantpartoftheconsumption-inducedemission,theratioofindirectemissiontoconsumption-inducedemissionhadrisenfrom69%to79%duringthesameperiod.Asignificantdifferenceinconsumption-inducedCO2emissionacrossdifferentincomegroupsanddifferentregionshasbeenobserved.CO2emissionpercapitaofhigherincomegroupsanddevelopedregionsincreasedfasterthanthatoflowerincomegroupsanddevelopingregions.ChanginglifestylehasdrivensignificantincreaseinCO2emission.Especially,increasesinprivatetransportexpenditure(forexample,vehicleexpenditure)andhousebuildingexpenditurearekeydrivingfactorsofgrowthinconsumption-inducedCO2emission.TherearebigdifferencesintheamountofCO2emissioninducedbychangeinlifestyleacrossdifferentincomegroupsandprovinces.Itcanbeexpectedthatlowerincomehouseholdsanddevelopingregionswillincreaseconsumptiontoimprovetheirlivingswithincomegrowthinthefuture,whichmayinducemuchmoreCO2emission.AreasonablelevelofCO2emissionisnecessarytosatisfyhumanneedsandtoimprovelivingstandard,butanoticeablefactisthatCO2emissionpercapitainducedbyhouseholdconsumptionindevelopedareasofChinahadreachedaquitehighlevel.Adjustmentinlifestyletowardsalow-carbonsocietyisinurgentneed.
简介:为探究并比较淡水鱼种日本青鳉早期发育阶段对Cu2+和Cd2+等重金属胁迫的响应,在实验室通过半静态方式,对日本青鳉受精卵和仔稚鱼分别进行了48h和96h急性毒性实验。结果表明:Cu2+对日本青鳉胚胎24、48h-LC_(50)分别为8.164mg·L(-1)和6.965mg·L(-1);Cd2+对日本青鳉胚胎24、48h-LC_(50)分别为63.084mg·L(-1)和53.093mg·L(-1);较低浓度组Cu(2+)(≤1.97mg·L(-1))时日本青鳉胚胎的发育速率快于对照组,而较高浓度组(≥3.87mg·L(-1))胚胎的发育速率则慢于对照组;与Cu(2+)略有不同,无论浓度高低Cd(2+)对胚胎的孵化速率均产生抑制作用;Cu(2+)和Cd(2+)质量浓度分别高于1.97mg·L(-1)和19.68mg·L(-1)时,两种重金属离子均显著降低胚胎的孵化率(P〈0.05)。Cu(2+)对日本青鳉初孵仔鱼24、48、72和96h-LC_(50)分别为5.361mg·L(-1)、2.844mg·L(-1)、2.020mg·L(-1)和1.352mg·L(-1);Cd(2+)对日本青鳉初孵仔鱼24、48、72和96h-LC_(50)分别为15.907mg·L(-1)、10.550mg·L(-1)、7.986mg·L(-1)和6.346mg·L(-1);Cu(2+)对日本青鳉稚鱼24、48、72和96h-LC_(50)分别为5.732mg·L(-1)、4.037mg·L(-1)、2.498mg·L(-1)和1.955mg·L(-1);Cd(2+)对日本青鳉稚鱼的24、48、72和96h-LC_(50)分别为16.419mg·L(-1)、11.745mg·L(-1)、8.516mg·L(-1)和6.776mg·L(-1)。与其它淡水水生生物相比,日本青鳉仔稚鱼对铜和镉离子较为敏感。
简介:AftertheKyotoProtocolwasimplemented,carbonleakageexertsgreatinfluencesoninternationaltradeandeconomy.Tradecreatesamechanismforconsumerstoshiftenvironmentalpollutionassociatedwiththeirconsumptiontoothercountries.ChinahasovertakentheU.S.astheworld'sbiggestCO2emittersince2006.AsChina'ssecondlargesttradepartner,theU.S.hasthebiggesttradedeficitwithChinawhichhasarousedalotofdisputesbetweenthetwoparties.ButsofartheassessmentsofthetradeimbalanceofChina-U.S.havepaidlittleattentiontoenvironmentalimpactsassociatedwiththetradeimbalance.Appliedaninput-outputapproach,thearticleestimatestheamountofCO2embodiedinChina-U.S.tradeduring1997-2007.ItwasfoundthatthroughtradewithChina,theU.S.reduceditsCO2emissionscomparedwithanon-tradescenario.Duetothegreatercarbon-intensityandrelativelylessefficientproductionprocessesofChineseindustry,China-U.S.traderesultedinmoreCO2emissionsinChinaandtheworld.Intheend,thearticlegivessomesuggestions:itisequalandsustainablethattheinternationalaccountingmethodologiesshouldbeimproved,forCO2emissionsresponsibilitymustbedesignedtoaccountforthedynamicnatureofinternationaltrade.
简介:EstablishingpositiveandurgenttargetsforCO2reductionandemissionpeak,andpromotingenergyconservationandenergystructureadjustmentareamongthestrategiestoaddressglobalclimatechangeandCO2emissionsreduction.Theyarealsomeanstobreakthroughtheconstraintsofdomesticresourcesandenvironment,andinternalneeds,toachievesustainabledevelopment.Generallyspeaking,acountry’sCO2emissionpeakappearsafterachievingurbanizationandindustrialization.Bythen,connotativeeconomicgrowthwillappear,GDPwillgrowslowly,energyconsumptionelasticitywilldecrease,andenergyconsumptiongrowthwillslowdown-dependentmainlyonnewandrenewableenergies.Fossilfuelconsumptionwillnotincreasefurther.WhenCO2emissionreachesitspeak,theannualreductionrateofCO2intensityofGDPisgreaterthanGDPannualgrowthrate;andtheannualreductionrateofCO2intensityofenergyuseisgreaterthantheannualgrowthrateofenergyconsumption.Therefore,threeimportantapproachestopromotionofCO2emissionpeakcanbeconcluded:maintainingreasonablecontrolofGDPgrowth,strengtheningenergyconservationtosignificantlyreducetheGDPenergyintensity,andoptimizingtheenergymixtoreducetheCO2intensityofenergyuse.Byaround2030,Chinawillbasicallyhavecompleteditsrapiddevelopmentphaseofindustrializationandurbanization.ConnotativeeconomicgrowthwillappearwiththeaccelerationofindustrialstructureadjustmentThetargetofGDPenergyintensitywillstillbetomaintainanaverageannualreductionof3%orhigher.Theproportionofnon-fossilfuelswillreach20-25%,andtheaimwillbetomaintainanaverageannualgrowthrateof6-8%.Thetotalannualenergydemandgrowthof1.5%willbesatisfiedbythenewlyincreasedsupplyofnon-fossilfuels.TheannualdeclineinCO2intensityofGDPwillreach4.5%orhigher,whichiscompatiblewithanaverageannualGDPgrowth