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简介：InAugust27th,somestudentsofGrade6wenttoLeShan.

简介：开心网上做投票,很多投票的都有这样的选项"我来自火星"。于是,在网络用语中,"我来自火星"成了对事物不知所以的代名词。但是火星上可曾有人居住呢?带着这样的问题,我们启动了时光机器,来到了未来的火星上一探究竟。

简介：Monitoring.We,ecologists,hearthewordnearlyeveryday.Fromthemostunexpectedcornersthiswordspringsout,muchusedandabused.Oneonehand,itisoftenusedbymypeerstojustifytheirwork,theirprojectoreventheirexistenceasscientists.Theyclaimtodousefulwork,becausetheymonitorsomephenomenonoranother.This,goesthear-

简介：Inthispaper,weconsiderFPUlatticeswithparticlesofunitmass.Thedynamicsofthesystemisdescribedbytheinfinitesystemofsecondorderdifferentialequationsqn=U′(qn+1-qn)-U′(qn-qn-1),n∈Z,whereqndenotesthedisplacementofthen-thlatticesiteandUisthepotentialofinteractionbetweentwoadjacentparticles.InspiredbypreviousworkduetoSzulkinandWeth（Groundstatesolutionsforsomeindefinitevariationalproblems,J.Funct.Anal.,257（2009）,3802-3822）,weinvestigatetheexistenceofsolitarygroundwaves,i.e.,nontrivialsolutionswithleastpossibleenergy.

简介：Wediscusssomeclassesoftravellingsalesmanproblemswithsumandbottleneckobjectiveswhichcanbesolvedefficientlyandposethequestionhowsuchspecialcasescanleadtogoodheuristics.

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简介：AtthestartofournewJournalofBiosafety,IwaspromptedbymyCo-Editors-in-Chief,ProfessorWanandProfessorYou,toprovideregularreviewsorupdatesonbiosafetyforourreaders,giventhatImostlyresideoutsideChina,andhavemanyinternationalconnections.Thatisaverybigtask,andIwasnotsurethatIcoulddoitasthejournaldemands.However,Ihadthoughtthatinalighterway,IcouldattempttopresentmythoughtsonsomeissuesthatIfeelareofimportancetoday.Chinaisveryquicklyopeningtotheworld,economically,scientifically,andinmanyotherfields,andformanycolleaguesinsideandoutsideChina,thisisanewsituation.Duringmycareer,IhaveworkedinseveralcountriesofEurope,inNewZealand,andhadprojectsonothercontinents.Thisgavemeexperiencesindifferentpartsofourglobe,andIfeelthatallofus,ecologists,havetostartthinkingmorewidely,andbeawareofdevelopments,especiallyofhumanimpacts,onfarawayplaces.Somyviewwhenwritingtheseessayswilltrytobebothlocalandglobal.ThereforeIhavechosentheoveralltitleforthisseriesofessays'Thoughtsofatravellingecologist'.Belowyouwillbeabletoreadthefirstone-Ihopeyouwillenjoythem.Ifyoufeelliketoadd,orcommentonmyessays,pleasefeelfreetodoso.Anyfeedbackwillbemostwelcome.

简介：Natureconservationneedspeoplewhocareaboutnature,andtheeffortstoconvincepeopletocareaboutthefateofnaturehasextensivelyreliedonselectedcharismaticspecies,the'conservationicons'.Onefamousexampleisthegreatpanda,Ailuropodamelanoleuca,wellknownastheWorldWideFundforNature(WWF)logo.Whenitcomestoinvertebrates,the

简介：Byusingthebifurcationtheoryofdynamicalsystemstothecouplednonlinearwaveequations,theexistenceandstabilityofperiodicwavesolutionsbyHopfbifurcationsareobtained.Theoryoftravellingwavewasappliedtotransformakindofcouplednonlinearwaveequationsintothree-dimensiondynamicalsystems.Underdifferentparametricconditions,varioussufficientconditionstoguaranteetheexistenceandstabilityoftheabovesolutionsaregiven.

简介：Theauthordemonstratethatthetwo-pointboundaryvalueproblem{p′(s)=f′(s)-λp^β(s)fors∈(0,1);β∈(0,1),p(0)=p(1)=0,p(s)>0ifs∈(0,1),hasasolution(λ^-，p^-（s）),where|λ^-|isthesmallestparameter,undertheminimalstringentrestrictionsonf(s),byapplyingtheshootingandregularizationmethods.Inaclassicpaper,Kohmogorovet.al.studiedin1937aproblemwhichcanbeconvertedintoaspecialcaseoftheaboveproblem.Theauthoralsousethesolution(λ^-,p^-(s))toconstructaweaktravellingwavefrontsolutionu(x,t)=y(ξ),ξ=x-Ct,C=λ^-N/(N+1),ofthegeneralizeddiffusionequationwithreactionδ/δx（k（u）|δu/δx|^n-1δu/δx)-δu/δt=g（u），whereN>0,k(s)>0a.e.on(0,1),andf(a):=n+1/N∫0ag(t)k^1/N(t)dtisabsolutelycontinuousou[0,1],whiley(ξ)isincreasingandabsolutelycontinuouson(-∞,+∞)and(k(y(ξ))|y′(ξ)|^N)′=g(y(ξ))-Cy′(ξ)a.e.on(-∞，+∞）,y(-∞)=0,y(+∞)=1.

简介：Abstract.ARiccatiequationinvolvingaparameterandsymboliccomputationareusedtouni-formlyconstructthedifferentformsoftravellingwavesolutionsfornonlinearevolutionequa-tions.Itisshownthatthesignoftheparametercanbeappliedinjudgingtheexistenceofvari-ousformsoftravellingwavesolutions.Anefficiencyofthismethodisdemonstratedonsomee-quations,whichincludeBurgers-Huxleyequation,Caudrey-Dodd-Gibbon-Kawadaequation,gen-eralizedBenjamin-Bona-MahonyequationandgeneralizedFisherequation.

简介：TheconditionofourEarthischanging,anditischangingduetohumandominance.Werealisedthatourinfluenceonbiotaisoverwhelming,buildinguptoamassextinction,thesixthinthehistoryoflifeonEarth.Thelaterthisrealisationisturnedintoactiontodecreaseourfatalinfluence,theworsearethechancesofthesurvivalofthehumanrace.Howcanwefail?Oneplausiblescenarioisthatthiscanhappenviathelossofecologicalservices

简介：WeliveintheAgeofExtinctions-thecallfornamingourtime＂Anthropocene＂isnomorethanhubrisandescapismfromthiscolossalsin.Althoughthe6thmassextinctionhaspossiblyalreadystarted（Barnoskyetal.,2011）,anditmayprovethelargestsofartobeenduredbylifeonEarth,effortsareneedednottoturnthisintotheAgeofLoneliness,whenhumansmayfindthemselvesMastersoftheEarthbutalone（Wilson,2014）.

简介：SomenewexacttravellingwaveandperiodsohltionsofdiscretenonlinearSchroedingerequationarefoundbyusingahyperbolictangentfunctionapproach,whichwasusuallypresentedtofindexacttravellingwavesolutionsofcertainnonlinearpartialdifferentialmodels.Nowwecanfurtherextendthenewalgorithmtoothernonlineardifferentialdifferentmodels.

简介：Theultrafastchargedynamicsfollowingtheinteractionofanultra-intenselaserpulsewithafoiltargetleadstothelaunchofanultra-short,intenseelectromagnetic（EM）pulsealongawireconnectedtothetarget.Duetothestrongelectricfield（oftheorderofGVm^-1）associatedtosuchlaser-drivenEMpulses,thesecanbeexploitedinatravelling-wavehelicalgeometryforcontrollingandoptimizingtheparametersoflaseracceleratedprotonbeams.ThepropagationoftheEMpulsealongahelicalpathwasstudiedbyemployingaprotonprobingtechnique.Thepulse-carryingcoilwasprobedalongtwoorthogonaldirections,transverseandparalleltothecoilaxis.Thetemporalprofileofthepulseobtainedfromthetransverseprobingofthecoilisinagreementwiththepreviousmeasurementsobtainedinaplanargeometry.Thedataobtainedfromthelongitudinalprobingofthecoilshowsaclearevidenceofanenergydependentreductionoftheprotonbeamdivergence,whichunderpinsthemechanismbehindselectiveguidingoflaser-drivenionsbythehelicalcoiltargets.

简介：在这份报纸，概括Dodd-Bullough-Mikhailov方程被学习。周期的波浪和无界的波浪解决方案的存在被使用动态系统的分叉理论的方法证明。在不同参量的条件下面，保证上述答案的存在的各种各样的足够的条件被给。上述旅行答案的一些准确明确的参量的代表被获得。

简介：Inthispaper,anextendedmethodisproposedforconstructingnewformsofexacttravellingwavesolutionstononlinearpartialdifferentialequationsbymakingamoregeneraltransformation.Forillustration,weapplythemethodtotheasymmetricNizhnik-Novikov-VesselovequationandthecoupledDrinfel'd-Sokolov-WilsonequationandsuccessfullycoverthepreviouslyknowntravellingwavesolutionsfoundbyChen'smethod[Y.Chen,etal.Chaos,SolitonsandFractals22(2004)675;Y.Chen,etal.Int.J.Mod.Phys.C4(2004)595].

简介：Bythemethodofdynamicalsystem,weconstructtheexacttravellingwavesolutionsofanewHamiltonianamplitudeequationandtheOstrovskyequation.Basedonthismethod,thenewexacttravellingwavesolutionsofthenewHamiltonianamplitudeequationandtheOstrovskyequation,suchassolitarywavesolutions,kinkandanti-kinkwavesolutionsandperiodictravellingwavesolutions,areobtained,respectively.

简介：Byusingthemethodofdynamicalsystem,theexacttravellingwavesolutionsofthecouplednonlinearSchrdinger-KdVequationsarestudied.Basedonthismethod,allphaseportraitsofthesystemintheparametricspacearegiven.Allpossibleboundedtravellingwavesolutionssuchassolitarywavesolutionsandperiodictravellingwavesolutionsareobtained.WiththeaidofMaplesoftware,thenumericalsimulationsareconductedforsolitarywavesolutionsandperiodictravellingwavesolutionstothecouplednonlinearSchrdinger-KdVequations.Theresultsshowthatthepresentedfindingsimprovetherelatedpreviousconclusions.