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500 个结果
  • 简介:ABSTRACT:Westudytheevolutionofsingleellipticvortexringforinitialaspectratio(AR)=2,4,6.TheincompressibleNavier-Stokesequationsaresolvedbyadealiasedpseudo-spectralmethodwith64~3gridpointsinaperiodiccube.WefindthattherearethreekindsofvortexmotionasARincreasesandvortexbifurcationoccursatacertainAR.Theprocessesofadvection,interaction,anddecayofvortexringareanalyzed.Numericalresultscoincidewithexperimentsandothernumericalsimulations.

  • 标签: ELLIPTIC VORTEX RING DNS pseudo-spectral method
  • 简介:Anewsimilarsingle-differencemathematicalmodel(SS-DM)anditscorrespondingalgorithmareadvancedtosolvethedeformationofmonitoringpointdirectlyinsingleepoch.ThemethodforbuildingtheSSDMisintroducedindetail,andthemainerrorsourcesaffectingtheaccu-racyofdeformationmeasurementareanalyzedbriefly,andthebasicalgo-rithmandstepsofsolvingthedeform-ationarediscussed.Inordertovalidatethecorrectnessandtheaccuracyofthesimilarsingle-differencemodel,thetestwithfivedualfrequencyreceiversiscarriedoutonaslidewaywhichmovedinplaneinFeb.2001.Inthetest,fivesessionsareobserved.Thenumericalresultsoftestdatashowthattheadvancedmod-eliscorrect.

  • 标签: 运算法则 GPS 变形监测 数学模型
  • 简介:Thedendriticcellsystemcontainsconventionaldendriticcells(DCs)andplasmacytoidpre-dendriticcells(pDCs).BothDCsandpDCsarebonemarrowderivedcells.AlthoughthecommonfunctionsofDCsareantigen-processingandT-lymphocyteactivation,theydifferinsurfacemarkers,migratorypatterns,andcytokineoutput.ThesedifferencescandeterminethefateoftheTcellstheyactivate.SeveralsubsetsofmatureDCshavebeendescribedinbothmouseandhumanandthedevelopmentalprocessesofthesespecializedDCsubsetshavebeenstudiedextensively.TheoriginalconceptthatallDCswereofmyeloidoriginwasquestionedbyseveralrecentstudies,whichdemonstratedthatinadditiontotheDCsderivedfrommyeloidprecursors,someDCscouldalsobeefficientlygeneratedfromlymphoid-restrictedprecursors.Moreover,ithasbeenshownrecentlythatbothconventionalDCsandpDCscanbegeneratedbytheFlt3expressinghemopoieticprogenitorsregardlessoftheirmyeloid-orlymphoid-origin.ThesefindingssuggestanearlydevelopmentalflexibilityofprecursorsforDCsandpDCs.ThisreviewsummarizessomerecentobservationsonthedevelopmentofDCsysteminbothhumanandmouse.

  • 标签: 树枝状细胞系统 DCS MHC 活化作用 T细胞 免疫学
  • 简介:今日任务蓓蒂买新手机时必须做哪些决定?会话A(赛门站在邮局里。)蓓蒂:赛门,所以我的手机出了什么问题啊?赛门:我不确定耶,蓓蒂。我看过电池,电池没问题,但你也知道这个手机很旧了。

  • 标签: 中等教育 英语 阅读教材 课外阅读
  • 简介:TcellhomeostasiscommonlyreferstothemaintenanceofrelativelystableTcellnumbersintheperipherallymphoidorgans.AmongthelargenumbersofTcellsintheperiphery,Tcellsexhibitstructuraldiversity,I.e.,theexpressionofadiverserepertoireofTcellreceptors(TCRs),andfunctionaldiversity,I.e.,thepresenceofTcellsatna(I)ve,effector,andmemorydevelopmentalstages.AlthoughthehomeostasisofTcellnumbershasbeenextensivelystudied,investigationofthemechanismsunderlyingthemaintenanceofstructuralandfunctionaldiversityofTcellsisstillatanearlystage.ThefundamentalfeaturethroughoutTcelldevelopmentistheinteractionbetweentheTCRandeitherselforforeignpeptidesinassociationwithMHCmolecules.Inthisreview,wepresentevidenceshowingthathomeostasisofTcellnumberanddiversityismediatedthroughcompetitionforlimitingresources.ThenumberofTcellsismaintainedthroughcompetitionforlimitingcytokines,whereasthediversityofTcellsismaintainedbycompetitionforself-peptide-MHCcomplexes.Inotherwords,diversityoftheself-peptiderepertoirelimitsthestructural(TCR)diversityofaTcellpopulation.Wespeculatethatcognatelowaffinityself-peptides,actingasweakagonistsandantagonists,regulatethehomeostasisofTcelldiversitywhereasnon-cognateornullpeptideswhichareextremelyabundantforanygivenTCR,maycontributetothehomeostasisofTcellnumberbyprovidingsurvivalsignals.Moreover,self-peptidesandcytokinesmayformspecializednichesfortheregulationofTcellhomeostasis.

  • 标签: 动态平衡 T细胞 细胞多样性 免疫器官
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  • 简介:Redbloodcells(RBC)’flickeringpresentthedynamicpropertiesofthecytomembrane.Itscomplexitycouldbeusedforaginganalysisortheevaluationforthestoragequality.Theflickeringactivityisakindofreversibleperpendicularmotionofthespecifiedpixel.Therefore,thecomplexityanalysisdependsonthereliabledetectionoftemporalvariationforthegray-scalevaluesfromeachpixelofthecells.Inthispaper,weimprovedourpreviousworkonthescreeningofthehorizontaldriftedcellswithasurfacebasedoncellregistrationmethodandtheeffectofGSMexposuretothedynamicpropertiesoftheRBCsintermsofmulti-scalesampleentropywaspresentedinthepaper.

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  • 简介:Cancercelldormancyisthemaincauseofcancerrecurrenceandfailureoftherapyasdormantcellsevadenotonlytheanticancerdrugsbutalsothehostimmunesystem.Thesedormantcellsveilthemselvesfromdetectionbyimagingand/orusingbiomarkers,whichimposesanadditionalproblemintargetingsuchcells.Asimilarformofhibernationprocessknownasencystationisstudiedindetailforpathogenicunicellulareukaryoticmicroorganisms.Byexaminationusingmicroarraygeneexpressionprofiles,immunocytochemistrytools,andsiRNAsduringtheprocessofencystation,understandingthecovertfeaturesofcancercelldormancyasproposedcouldbepossible.Thisknowledgecanbeextendedtodormantcancercellstouncoverthemechanismsthatunderliethisghost,yetdangerousstateofhumancancers.Weproposeastrategytoinducedormancyandexitthisstatebyapplicationofknowledgegainedfromtheencystationinductionandretrievalprocessesinpathogeniceukaryoticmicroorganisms.Giventhatearlydetectionandcharacterizationofdormantmalignanttumorcellsisimportantasageneralstrategytomonitorandpreventthedevelopmentofovertmetastaticdisease,thishomologymayenablethedesignoftherapiesthatcouldeitherawakethedormantcellfromdormancytomakeitavailablefortherapiesorprolongsuchaphasetomakecancerappearasachronicdisease

  • 标签: 休眠细胞 真核细胞 癌细胞 隐藏 免疫细胞化学 恶性肿瘤细胞
  • 简介:RNAi是双链RNA介导的、序列特异性的转录后基因沉默,自1998年发现至今已有很大进展.本文综述了RNA干涉的分子机理及其应用研究进展.

  • 标签: RNAI 共抑制 功能基因组 DSRNA siRNA 基因沉默
  • 简介:1IntroductionOverthepastdecade,FlexibleManufacturingSystems(FMS)havereceivedsignificantattentionfromresearchersasanewmanufac...

  • 标签: FLEXIBLE MANUFACTURING SYSTEM PETRI NET process
  • 简介:Theintroductionofnext-generationsequencing(NGS)technologyintestingforhereditarycancersusceptibilityallowstestingofmultiplecancersusceptibilitygenessimultaneously.Whiletherearemanypotentialbenefitstoutilizingthistechnologyinthehereditarycancerclinic,includingefficiencyoftimeandcost,therearealsoimportantlimitationsthatmustbeconsidered.Thebestpanelforthegivenclinicalsituationshouldbeselectedtominimizethenumberofvariantsofunknownsignificance.Theinclusioninpanelsoflowpenetranceornewlyidentifiedgeneswithoutspecificactionabilitycanbeproblematicforinterpretation.Geneticcounselorsareanessentialpartofthehereditarycancerriskassessmentteam,helpingthemedicalteamselectthemostappropriatetestandinterprettheoftencomplexresults.Geneticcounselorsobtainanextendedfamilyhistory,counselpatientsontheavailabletestsandthepotentialimplicationsofresultsforthemselvesandtheirfamilymembers(pre-testcounseling),explaintopatientstheimplicationsofthetestresults(post-testcounseling),andassistintestingfamilymembersatrisk.

  • 标签: 遗传性 癌症 遗传评价 检测 测序 基因测试
  • 简介:Thispaperstudiesatwostagesupplychainwithadominantupstreampartner.ManufactureristhedominantpartnerandoperatesinaJust-in-Timeenvironment.Productionisdoneinasinglemanufacturinglinecapableofproducingtwoproductswithoutstoppingtheproductionforswitchingfromoneproducttotheother.Themanufacturerimposesconstraintsonthedistributorbyadheringtohisfavorableproductionschedulewhichminimizeshismanufacturingcost.Distributorontheotherhandcaterstoretailers'orderswithoutincurringanyshortagesandisresponsibleformanagingtheinventoryoffinishedgoods.Adheringtomanufacturer'sschedulemayleadtohighinventorycarryingcostsforthedistributor.Distributor'sproblem,whichistofindanoptimaldistributionsequencewhichminimizesthedistributor'sinventorycostundertheconstraintimposedbythemanufacturerisprovedNP-HardbyManojetal.(2008).Therefore,solvinglargesizeproblemsrequireefficientheuristics.Wedevelopalgorithmsforthedistributionproblembyexploitingitsstructuralproperties.Weproposetwoheuristicsandusetheirsolutionsintheinitialpopulationofageneticalgorithmtoarriveatsolutionswithanaveragedeviationoflessthan3.5%fromtheoptimalsolutionforpracticalsizeproblems.

  • 标签: 库存成本 合作伙伴 生产成本 供应链 上游 序列
  • 简介:Denovosequencingisoneofthemostpromisingproteomicstechniquesforidentificationofproteinposttranslationmodifications(PTMs)instudyingproteinregulationsandfunctions.WehavedevelopedacomputertoolPRIMEforidentificationofbandyionsintandemmassspectra,akeychallengingproblemindenovosequencing.PRIMEutilizesafeaturethationsofthesameanddifferenttypesfollowdifferentmass-differencedistributionstoseparatebfromyionscorrectly.Wehaveformulatedtheproblemasagraphpartitionproblem.Alinearinteger-programmingalgorithmhasbeenimplementedtosolvethegraphpartitionproblemrigorouslyandefficiently.TheperformanceofPRIMEhasbeendemonstratedonalargeamountofsimulatedtandemmassspectraderivedfromYeastgenomeanditspowerofdetectingPTMshasbeentestedon216simulatedphosphopeptides.

  • 标签: 计算机 PRIME PTMS 光谱扫描系统 人工分析扫描系统
  • 简介:AbstractIntroduction:Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous malignancy, and its pathogenesis might relate to ultraviolet light and Merkel cell polyomavirus infection. MCC in the Chinese population is uncommon.Here, we present a case of MCC that occurred based on widespread actinic keratosis (AK) in a Chinese female.Case report:An 82-year-old woman presented with two rapidly enlarging and rupture lesions on the face for 1 year. Biopsy was suggestive of squamous cell carcinoma (SCC) on the forehead and MCC on the left cheek. The patient had a history of generalized AK for 3 years. The lesion on the left cheek was also revealed as an AK by histopathological examination 1 year ago. Complete surgical resection was performed to remove the two malignancies.Discussion:The co-occurrence of AK, SCC, and MCC in a Chinese woman is unusual. Immunohistopathological examination is vital for correct diagnosis. The three tumors, in this case, may originate from two different precursor cells and are affected by the same carcinogen. Alternatively, they may come from the same pluripotent epidermal stem cells, and chronic exposure to ultraviolet light and Merkel cell polyomavirus lead to the formation of different types of tumors. The coexist of MCC with other cutaneous tumors provided a train of thought for exploring the origin of MCC.Conclusion:We reported a rare co-existence phenomenon of MCC associated with AK and SCC. Hence, long-term follow-up and early treatment are imperative for patients with premalignant lesions, such as widespread AK.

  • 标签: Merkel cell carcinoma squamous cell carcinoma actinic keratosis concurrence case report
  • 简介:TCELLRECEPTORGENEREARRANGEMENTANALYSISINTHEPRIMARYCUTANEOUSTCELLLYMPHOMAQiuBingsen邱丙森WangPing1王平GaoHongyang2高红阳ShangYifei2...

  • 标签: PRIMARY CUTANEOUS T cell LYMPHOMA PCR
  • 简介:AbstractObjective:Pemphigus is a life threatening autoimmune bullous disease which involves the skin and mucous membranes of the stratified squamous epithelium. The global distribution of Pemphigus varies according to genetic, ethnic, socioeconomic, and cultural backgrounds. The purpose of our study is to evaluate the epidemiological features of pemphigus a single center in Morocco and compare our results with those reported elsewhere.Methods:A retrospective analysis was conducted of 302 pemphigus patients seen between 1990 and 2020 in the Dermatology Department of Ibn Sina Hospital (Rabat, Morocco). We further collected all the Moroccan scientific researches published by now to compare.Results:The average annual incidence was 0.32/100,000 inhabitants. The incidence doubled to 0.72 in 2020. The most common variant was pemphigus vulgaris (125 cases) followed by pemphigus erythematosus (99 cases), pemphigus foliaceous (40 cases), and vegetans (27 cases). The female to male ratio was 0.75, the average age at onset was 53 years old and the mean duration of the disease before diagnosis was 13.36 months.Conclusion:This study joins the main characteristics of pemphigus in the Maghreb and around the world (pemphigus vulgaris most frequent subtype). In 2020, an epidemiological peak occurred during the coronavirus disease 2019 pandemic; probably related to stress and delayed time consultation for fear of contracting the severe acute respiratory syndrome coronavirus 2.

  • 标签: pemphigus epidemiology Rabat Morocco autoimmune bullous disease desmoglein
  • 简介:Thispaperdealswithamethodologyforsinglegatelocationoptimizationforplasticinjectionmold.Theobjectiveofthegateoptimizationistominimizethewarpageofinjectionmoldedparts,becausewarpageisacrucialqualityissueformostinjectionmoldedpartswhileitisinfluencedgreatlybythegatelocation.Featurewarpageisdefinedastheratioofmaximumdisplacementonthefeaturesurfacetotheprojectedlengthofthefeaturesurfacetodescribepartwarpage.Theoptimizationiscombinedwiththenumericalsimulationtechnologytofindtheoptimalgatelocation,inwhichthesimulatedannealingalgorithmisusedtosearchfortheoptimum.Finally,anexampleisdiscussedinthepaperanditcanbeconcludedthattheproposedmethodiseffective.

  • 标签: 注射模拟 最优化 塑料材料 成型加工