简介:Cellulasesareimportantglycosylhydrolases(GHs)thathydrolyzecellulosepolymersintosmalleroligosaccharidesbybreakingthecelluloseβ(1→4)bonds,andtheyarewidelyusedtoproducecellulosicethanolfromtheplantbiomass.N-linkedandO-linkedglycosylationswereproposedtoimpactthecatalyticefficiency,cellulosebindingaffinityandthestabilityofcellulasesbasedonobservationsofindividualcellulases.Asfarasweknow,therehasnotbeenanysystematicanalysisofthedistributionsofN-linkedandO-linkedglycosylatedresiduesincellulases,mainlyduetothelimitedannotationsoftherelevantfunctionaldomainsandtheglycosylatedresidues.Wehavecomputationallyannotatedthefunctionaldomainsandglycosylatedresiduesincellulases,andconductedasystematicanalysisofthedistributionsoftheN-linkedandO-linkedglycosylatedresiduesintheseenzymes.ManyN-linkedglycosylatedresidueswereknowntobeintheGHdomainsofcellulases,buttheyarethereprobablyjustbychance,sincetheGHdomainusuallyoccupiesmorethanhalfofthesequencelengthofacellulase.OuranalysisindicatesthattheO-linkedglycosylatedresiduesaresignificantlyenrichedinthelinkerregionsbetweenthecarbohydratebindingmodule(CBM)domainsandGHdomainsofcellulases.Possiblemechanismsarediscussed.
简介:Amodelhelicopterismoredifficulttocontrolthanitsfullscalecounterpart.Thisisduetoitsgreatersensitivitytocontrolinputsanddisturbancesaswellashigherbandwidthofdynamics.Thisworkisfocusedondesigningpracticaltrackingcontrollerforasmallscalehelicopterfollowingpredefinedtrajectories.Atrackingcontrollerbasedonoptimalcontroltheoryissynthe-sizedasapartofthedevelopmentofanautonomoushelicopter.Someissueswithregardstocontrolconstraintsareaddressed.Theweightingbetweenstatetrackingperformanceandcontrolpowerexpenditureisanalyzed.Overallperformanceofthecontroldesignisevaluatedbasedonitstimedomainhistoriesoftrajectoriesaswellascontrolinputs.
简介:Inspiredbythecoarse-to-finevisualperceptionprocessofhumanvisionsystem,anewapproachbasedonGaussianmulti-scalespacefordefectdetectionofindustrialproductswasproposed.ByselectingdifferentscaleparametersoftheGaussiankernel,themulti-scalerepresentationoftheoriginalimagedatacouldbeobtainedandusedtoconstitutethemulti-variateimage,inwhicheachchannelcouldrepresentaperceptualobservationoftheoriginalimagefromdifferentscales.TheMultivariateImageAnalysis(MIA)techniqueswereusedtoextractdefectfeaturesinformation.TheMIAcombinedPrincipalComponentAnalysis(PCA)toobtaintheprincipalcomponentscoresofthemultivariatetestimage.TheQ-statisticimage,derivedfromtheresidualsaftertheextractionofthefirstprincipalcomponentscoreandnoise,couldbeusedtoefficientlyrevealthesurfacedefectswithanappropriatethresholdvaluedecidedbytrainingimages.Experimentalresultsshowthattheproposedmethodperformsbetterthanthegrayhistogram-basedmethod.Ithaslesssensitivitytotheinhomogeneousofillumination,andhasmorerobustnessandreliabilityofdefectdetectionwithlowerpseudorejectrate.
简介:Thepaperpresentsamulti-scalemodellingapproachforsimulatingmacromoleculesinfluidflows.Macromoleculetransportatlownumberdensitiesisfrequentlyencounteredinbiomedicaldevices,suchasseparators,detectionandanalysissystems.Accuratemodellingofthisprocessischallengingduetothewiderangeofphysicalscalesinvolved.Thecontinuumapproachisnotvalidforlowsoluteconcentrations,butthelargetimescalesofthefluidflowmakepurelymolecularsimulationsprohibitivelyexpensive.Apromisingmulti-scalemodellingstrategyisprovidedbythemeta-modellingapproachconsideredinthispaper.Meta-modelsarebasedonthecoupledsolutionoffluidflowequationsandequationsofmotionforasimplifiedmechanicalmodelofmacromolecules.Theapproachenablessimulationofindividualmacromoleculesatmacroscopictimescales.Meta-modelsoftenrelyonparticle-correctoralgorithms,whichimposelengthconstraintsonthemechanicalmodel.Lackofrobustnessoftheparticle-correctoralgorithmemployedcanleadtoslowconvergenceandnumericalinstability.AnewFAstLinearCOrrector(FALCO)algorithmisintroducedinthispaper,whichsignificantlyimprovescomputationalefficiencyincomparisonwiththewidelyusedSHAKEalgorithm.ValidationofthenewparticlecorrectoragainstasimpleanalyticsolutionisperformedandimprovedconvergenceisdemonstratedforssDNAmotioninalid-drivenmicro-cavity.
简介:QuestionsconcerningthefunctionalroleofthehollowregionofthebutterflyPyrameisatalanta(L.)scaleareexperimentallyinvestigated.Attentionwasinitiallydirectedtothisproblembyobservationofthecomplexmicrostructureofthebutterflyscaleaswellasotherstudiesindicatinghigherliftonbutterflywingscoveredwithscale.Theaerodynamicforcesweremeasuredfortwooscillatingscalemodels.ResultsindicatedthattheaircavityofanoscillatingmodelofthePyrameisatalanta(L.)scaleincreasedtheliftbyafactorof1.15andreducedthedampingcoefficientsbyafactorof1.38.Themodificationoftheaerodynamiceffectsonthemodelofbutterflyscalewasduetoanincreaseofthevirtualairmass,whichinfluencedthebody.Thehollowregionofthescaleincreasedthevirtualairmassbyafactorof1.2.Thevirtualmassofthebutterflyscalewiththehollowregionwasrepresentedasthesumofairmassoftwoimaginarygeometricalfigures:acircularcylinderaroundthescaleandaright-angledparallelepipedwithinthehollowregion.TheinteractionmechanismofthebutterflyPyrameisatalanta(L.)scalewithaflowwasdescribed.Thisnovelinteractionmechanismexplainedmostgeometricalfeaturesoftheairpermeablebutterflyscale(invertedV-profileoftheridges,nozzleofthetipedge,hollowregion,andopeningsoftheupperlamina)andtheirarrangement.
简介:Aglycosylphosphatidylinositol(GPI)anchorisacommonbutcomplexC-terminalpost-translationalmodificationofextracellularproteinsineukaryotes.HereweinvestigatetheproblemofcorrectlyannotatingGPI-anchoredproteinsforthegrowingnumberofsequencesinpublicdatabases.Wedevelopedacomputa-tionalsystem,calledFragAnchor,basedonthetandemuseofaneuralnet-work(NN)andahiddenMarkovmodel(HMM).Firstly,NNselectspotentialGPI-anchoredproteinsinadataset,thenHMMparsesthesepotentialGPIsig-nalsandrefinesthepredictionbyqualitativescoring.FragAnchorcorrectlypredicted91%ofalltheGPI-anchoredproteinsannotatedintheSwiss-Protdatabase.Inalarge-scaleanalysisof29eukaryoteproteomes,FragAnchorpredictedthatthepercentageofhighlyprobableGPI-anchoredproteinsisbetween0.21%and2.01%.ThedistinctivefeatureofFragAnchor,comparedwithothersystems,isthatittargetsonlytheC-terminusofaprotein,makingitlesssensitivetothebackgroundnoisefoundindatabasesandpossibleincompleteproteinsequences.Moreover,FragAnchorcanbeusedtopredictGPI-anchoredproteinsinalleukaryotes.Finally,byusingqualitativescoring,thepredictionscombinebothsensitivityandinformationcontent.Thepredictorispubliclyavailableathttp://navet.ics.hawaii.edu/~fraganchor/NNHMM/NNHMM.html.
简介:中国白蜡规模昆虫,Ericeruspela,能在-30°C下面在温度在极其低的温度,和某overwintering个人展览supercooling幸存。调查E的深supercooling能力。pela,transcriptomic和proteomic分析被执行描出为overwintering女性的深supercooling能力负责的主要基因和蛋白质家庭。基因本体论(去)基因在表明小径和小径的激活mitogen的蛋白质kinase,钙,和PI3K-Akt包含了,这与可溶的糖,糖白酒和免费氨基酸的生合成联系的分析显示了的基因和染色体(KEGG)的分类和京都百科全书是主导的。为低温度的应力负责的蛋白质例如冷环境适应蛋白质,甘油生合成相关的酶和热吃惊蛋白质(HSP)被识别。然而,防冻剂蛋白质(法新社)都没通过顺序类似搜索方法被识别。一条随机的森林途径在proteome识别了388个通常认为的法新社。法新社基因ep-afp在Escherichiacoli被表示,并且表示蛋白质展出了0.97°C的一项热磁滞现象活动,建议它处于E的深supercooling能力的潜在的角色。pela。
简介:Climbingrobotsareofpotentialuseforsurveillance,inspectionandexplorationindifferentenvironments.Inparticular,theuseofclimbingrobotsforspaceexplorationcanallowscientiststoexploreenvironmentstoochallengingfortraditionalwheeleddesigns.Toadheretosurfaces,biomimeticdryadhesivesbasedongeckofeethavebeenproposed.Thesebiomimeticdryadhesivesworkbyusingmulti-scalecompliantmechanismstomakeintimatecontactwithdifferentsurfacesandadherebyusingVanderWaalsforces.Fabricationoftheseadhesiveshasfrequentlybeenchallenginghowever,duetothedifficultyincombiningmacro,microandnanoscalecompliance.Wepresentanallpolymerfootdesignforusewithahexapodclimbingrobotandafabricationmethodtoimprovereliabilityandyield.Ahighstrength,low-modulussilicone,TC-5005,isusedtoformthefootbaseandmicroscalefibresinonepiecebyusingatwopartmold.Amacroscalefootdesignisproducedusinga3Dprintertoproduceabasemold,whilelithographicdefinitionofmicroscalefibresinathickphotoresistformsthe‘hairs’ofthepolymerfoot.Theadhesionofthesiliconefibresbythemselvesorattachedtothemacrofootisexaminedtodeterminebeststrategiesforplacementandremovaloffeettomaximizeadhesion.Resultsdemonstratethesuccessfulintegrationofmicroandmacrocompliantfeetforuseinclimbingonavarietyofsurfaces.
简介:Overthelastdecade,computationalmethodshavebeenintensivelyappliedtoavarietyofscientificresearchesandengi-neeringdesigns.Althoughthecomputationalfluiddynamics(CFD)methodhasplayedadominantroleinstudyingandsimu-latingtransportphenomenainvolvingfluidflowandheatandmasstransfers,inrecentyears,othernumericalmethodsforthesimulationsatmeso-andmicro-scaleshavealsobeenactivelyappliedtosolvethephysicsofcomplexflowandfluid-interfaceinteractions.Thispaperpresentsareviewofrecentadvancesinmulti-scalecomputationalsimulationofbiomimeticsrelatedfluidflowproblems.Thestate-of-the-artnumericaltechniques,suchaslatticeBoltzmannmethod(LBM),moleculardynamics(MD),andconventionalCFD,appliedtodifferentproblemssuchasfishflow,electro-osmosiseffectofearthwormmotion,andself-cleaninghydrophobicsurface,andthenumericalapproachesareintroduced.Thenewchallengingofmodellingbiomi-meticsproblemsindevelopingthephysicalconditionsofself-cleanhydrophobicsurfacesisdiscussed.