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  • 简介:AbstractImportance:The process of brain development in children with developmental delay is not well known. Amide proton transfer-weighted (APTw) imaging is a novel molecular magnetic resonance imaging (MRI) technique that can noninvasively detect cytosolic endogenous mobile proteins and peptides involved in the myelination process, and may be useful for providing insights into brain development.Objective:To assess the contribution of amide proton transfer-weighted (APTw) imaging and magnetization transfer (MT) imaging to the evaluation of children with developmental delay (DD).Methods:Fifty-one patients with DD were recruited to this study. The patients were divided into two groups according to the state of myelination assessed on conventional magnetic resonance imaging (MRI). Thirty patients (10 girls, 20 boys; age range: 1-8 months; median age: 4 months) in group A showed delayed myelination on MRI , while 21 patients (3 girls, 18 boys; age range: 12-36months; median age: 25months) in group B showed normal myelination on MRI. Fifty-one age- and sex-matched children with normal developmental quotient (DQ) and normal MRI appearance were recruited as normal controls. Three-slice APTw/MT axial imaging was performed at the level of the centrum semiovale, the basal ganglia and the pons. Quantitative data of the MT ratio (MTR) and APTw were analyzed for multiple brain regions. Independent-sample t-tests were used to compare differences in APTw and MTR signals between the two DD groups and normal controls. Analysis of Covariance was conducted to correct the statistical results. The level of statistical significance was set to P < 0.05.Results:For group A, the MTR values were lower in all regions (P = 0.004-0.033) compared with the normal controls, while the APTw values were higher in the pons, middle cerebellar peduncle, corpus callosum, frontal white matter, occipital white matter and centrum semiovale (P = 0.004-0.040 ). For Group B, the MTR values were slightly reduced, and the APTw values were slightly increased compared with the normal controls, but the differences were not statistically significant (P > 0.05).Interpretation:For DD patients showing signs of delayed myelination on MRI, MTR and APTw imaging can help to diagnose myelination delay by quantifying semi-solid macromolecules and cytosolic endogenous mobile proteins and peptides at a molecular level, providing a new method for comprehensive evaluation of DD. For DD patients with normal myelination on MRI, the clinical values of MTR and APTw imaging remain to be explored.

  • 标签: Children Myelination Developmental delay Amide proton transfer Magnetization transfer
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  • 简介:AbstractThe developmental origins of health and disease theory states that environmental stresses during the early stages of life influence health and risk of developing non-communicable diseases throughout the lifespan of an individual. Developmental plasticity is thought to be a possible underlying mechanism. Here, I discuss a contrasting but complementary genetic hypothesis regarding the developmental origins of health and disease theory: crosstalk between the genomes of the parents and offspring is responsible for shaping and adapting responses to environmental stresses, regulating early growth and predisposition to non-communicable diseases. Genetic variants that are beneficial in terms of responses to early life stresses may have pleiotropic detrimental effects on health later in life, which may change the allele frequencies driven by selection on a population level. Genetic studies on the cohort of children born after assisted reproduction could provide insight regarding the genetic mechanisms of the developmental origins of health and disease theory.

  • 标签: assisted reproduction DOHaD genetic pleiotropy non-communicable diseases positive selection
  • 简介:这篇论文处理延期依赖者稳定问题因为有Markovian的单个系统跳参数和时间延期。一个延期依赖者条件为常规的考虑系统被建立,推动自由、随机的联盟者马厩。基于条件,保证结果的靠近环的系统常规的需要的州的反馈控制器的一个设计算法,免费的推动和随机的联盟者马厩以一套严格的线性矩阵不平等(LMI)被建议。数字例子显示出建议方法的有效性。

  • 标签: 稳定问题 广义系统 马尔可夫 时滞依赖 延迟 跳跃
  • 简介:Masterdevelopmentalpathways,suchasNotch,Wnt,andHedgehog,aresignalingsystemsthatcontrolproliferation,celldeath,motility,migration,andstemness.Thesesystemsarenotonlycommonlyactivatedinmanysolidtumors,wheretheydriveorcontributetocancerinitiation,butalsoinprimaryandmetastatictumordevelopment.Thereactivationofdevelopmentalpathwaysincancerstromafavorsthedevelopmentofcancerstemcellsandallowstheirmaintenance,indicatingthesesignalingpathwaysasparticularlyattractivetargetsforefficientanticancertherapies,especiallyinadvancedprimarytumorsandmetastaticcancers.Metastasisistheworstfeatureofcancerdevelopment.Thisfeatureresultsfromacascadeofeventsemergingfromthehijackingofepithelial-mesenchymaltransition,angiogenesis,migration,andinvasionbytransformingcellsandisassociatedwithpoorsurvival,drugresistance,andtumorrelapse.Inthepresentreview,wesummarizeanddiscussexperimentaldatasuggestingpivotalrolesfordevelopmentalpathwaysincancerdevelopmentandmetastasis,consideringthetherapeuticpotential.EmergingtargetedantimetastatictherapiesbasedonNotch,Wnt,andHedgehogpathwaysarealsodiscussed.

  • 标签: HEDGEHOG 肿瘤干细胞 NOTCH WNT 移相 信号系统
  • 简介:WeclonedcDNAsforXenopusaldolasesA,BandC.Thesethreealdolasegenesarelocalizedondifferentchromosomesasasinglecopygene.Intheadult,thealdolaseAgeneisexpressedextensivelyinmuscletissues,whereasthealdolaseBgeneisexpressedstronglyinkidney,liver,stomachandintestine,whilethealdolaseCgeneisexpressedinbrain,heartandovary.InoocytesaldolaseAandCmRNAs,butnotaldolaseBmRNA,areextensivelytranscribed.Thus,aldolaseAandCmRNAs,butnotBmRNA,occurabundantlyineggsasmaternalmRNAs,andstrongexpressionofaldolaseBmRNAisseenonlyafterthelateneurulastage.WeconcludethataldolaseAandCmRNAsaremajoraldolasemRNAsinearlystagesofXenopusembryogenesiswhichproceedsutilizingyolkastheonlyenergysource,aldolaseBmRNA,ontheotherhand,isexpressedonlylaterindevelopmentintissueswhicharerequiredfordietaryfructosemetabolism.WealsoisolatedtheXenopusaldolaseCgenomicgene(ca.12kb)andfoundthatitspromoter(ca.2kb)containsregionsnecessaryfortissue-specificexpressionandalsoaGCrichregionwhichisessentialforbasaltranscriptionalactivity.

  • 标签: ALDOLASE A B and C mRNAs
  • 简介:Theproblemofdelay-dependentrobuststabilityforsystemswithtitne-varyingdelayhasbeenconsidered.ByusingtheS-procedureandthePark'sinequalityintherecentissue,adelay-dependentrobuststabilitycriterionwhichislessconservativethanthepreviousresultshasbeenderivedfortime-delaysystemswithtime-varyingstructureduncertainties.Thesameideahasalsobeeneasilyextendedtothesystemswithnonlinearperturbations.Numericalexamplesillustratedtheeffectivenessandtheimprovementoftheproposedapproach.

  • 标签: 延迟标准 充分稳定性 时间变化构造不确定性 非线性干扰 线性矩阵不等式
  • 简介:Somenewlinearmatrixinequality(LMI)representationsfordeley-independentanddelay-dependentstabilityconditionsareobtainedbyintroducingadditionalmatricesandeliminatingtheproductcouplingofthesystemmatricesandtheLyapunovmatrices.Theresultsimproveconservativenessofthegivenconditionsfortheanalysisandthedesignoftime-delaysystemswithpolytopic-typeuncertainty.

  • 标签: 改进线性矩阵不等式 多发不确定性 完全控制 时间延迟系统
  • 简介:Itisafactthatthefeedbackdelayactuallyarieseindigitalcontrolsystems.Itisnecessarytomodifythestructureofdigitalcontrolsystemsanddevelopnewcontrolalgorithms,whichisdoneinthispaper.Agreatnumberofdigitalcomputersimulationexperimentshaveshowntheobviousadvantageofthenewalgorithms.

  • 标签: 迟滞反馈 数字控制 控制算法 脉冲转换函数
  • 简介:这篇论文处理为中立延期过滤问题的柔韧的延期依赖者H无穷微分系统。产生过滤器具有Luenberger观察员类型,;它保证过滤系统遗体asymptotically稳定;满足规定H无穷表演水平。Lyapunov稳定性理论;描述符模型转变被用于系统的分析;被期望作为与存在设计方法相比最不保守。一些例子被提供表明建议设计途径的有效性。

  • 标签: 中立系统 H无穷滤波器 稳定性 线性矩阵不等式
  • 简介:ThispaperinvestigatestherobuststochasticstabilityandH∞analysisforstochasticsystemswithtime-varyingdelayandMarkovianjump.Byusingthefreeweightingmatrixtechnique,i.e.,He’stechnique,andastochasticLyapunov-Krasovskiifunctional,newdelay-dependentcriteriaintermsoflinearmatrixinequalitiesarederivedforthetherobuststochasticstabilityandtheH∞disturbanceattenuation.Threenumericalexamplesaregiven.Theresultsshowthattheproposedmethodisefficientandmuchlessconservativethantheexistingresultsintheliterature.更多还原

  • 标签: 鲁棒稳定性 随机系统 时变时滞 时滞依赖 LYAPUNOV 线性矩阵不等式
  • 简介:植物高度的发展遗传基于NCII设计以二个环境条件从二组三线的indica混血儿米饭被分析,用添加剂主导的发展遗传模型和统计方法。结果证明米饭遗传型和环境条件能两个都影响植物高度,并且植物高度上的环境的效果与植物开发逐渐地减少了。添加剂和主导的效果两个都管理了植物高度的表演根本发展的阶段。然而,效果的度在米饭遗传型之中变化了。而且,在环境和遗传型之间的相互作用也影响了植物高度。基因效果不同至多发展的阶段。而且,添加剂效果的表示比主导的效果的更活跃。有环境的有条件的相互作用效果也在基因开发期间影响了植物高度,特别在早阶段。中间父母的杂种优势(HMP)与植物高度的发展阶段逐渐地增加了,并且而在更好的父母(HBP)上的杂种优势在遗传型之中显示出小差别,并且在以后的阶段保持稳定,在最近的阶段最大化,与积极数字价值。至多发展的阶段,有条件的HMP是确实重要的,当有条件的HBP是否定地重要的时。所有上面的结果建议HMP和HBP在所有发展时期和层次和方向有一些新表情是相当不同的。

  • 标签: 环境互作效应 籼型杂交水稻 发育遗传学 株高遗传 遗传学分析 杂种优势
  • 简介:Primordialgermcells(PGCs),asprecursorsofmammaliangermlineage,havebeengainingmoreattentionasanewresourceofpluripotentstemcells,whichbringagreatpossibilitytostudydevelopmentaleventsofgermcellinvitroandatanimallevel.EG4cellsderivedfrom10.5dayspostcoitum(dpc)PGCsof129/svJstrainmousewereestablishedandmaintainedinanundifferentiatedstate.WithanattempttostudythedifferentiationcapabilityofEG4cellswithareporterprotein:greenfluorescenceprotein,andthepossibleapplicationofEG4cellsintheresearchofgermcelldevelopment,wehavegeneratedseveralEG4-GFPcelllinesexpressingenhancedgreenfluorescenceprotein(EGFP)andstillmaintainingtypicalcharacteristicsofpluripotentstemcells.Then,thedifferentiationofEG4-GFPcellsinvitroaswellastheirdevelopmentalfateinchimericembryoswhichwereproducedbyaggregatingEG4-GFPcellsto8-cellstageembryoswerestudied.TheresultsshowedthatEG4cellscarryinggreenfluorescencehaveapotentialuseintheresearchofgermcelldevelopmentandotherrelatedstudies.

  • 标签: 胚胎生殖细胞 嵌合体 发育结局 基因转染 EGFP 绿色荧光蛋白
  • 简介:Diversityandcompositionoflepidopteranmicrobiotasarepoorlyinvestigated,especiallyacrossthedifferentdevelopmentalstages.Toimprovethisknowledge,wecharacterizethemicrobiotaamongdifferentdevelopmentalstagesoftheIndianmealmoth,Plodiainterpunctella,whichisconsideredoneofthemajorpestofcommoditiesworld-wide.Usingculture-independentapproachbasedonIllumina16SrRNAgenesequencingwecharacterizedthemicrobiotaoffourdevelopmentalstages:eggs,first-,andlast-instarlarvae,andadult.Atotalof1022bacterialOTUswereobtained,showingaquitediversifiedmicrobiotaassociatedtoalltheanalyzedstages.ThemicrobiotasassociatedwithP.interpunctellaresultedalmostconstantthroughoutthedevelopmentalstages,withapproximately77%ofbacterialOTUsbelongingtothephylumofProteobacteria.ThedominantbacterialgenusisrepresentedbyBurkholderia(?64%),followedbyPropionibacterium,Delftia,Pseudomonas,andStenotrophomonas.Acorebacterialcommunity,composedof139OTUs,wasdetectedinallthedevelopmentalstages,amongwhich112OTUswereassignedtothegenusBurkholderia.Aphylogeneticreconstruction,basedonthe16SrRNA,revealedthatourBurkholderiaOTUsclusteredwithBurkholderiacepaciacomplex,inthesamegroupofthoseisolatedfromthehemipteransGossypariaspuriaandAcanthococcusaceris.Thefunctionalprofiling,predictedonthebaseofthebacterial16SrRNA,indicatesdifferencesinthemetabolicpathwaysrelatedtometabolismofaminoacidsbetweenpreimaginalandadultstages.Wecanhypothesizethatbacteriamaysupporttheinsecthostduringpreimaginalstages.

  • 标签: BURKHOLDERIA Illumina sequencing Indian MEAL MOTH
  • 简介:Inthispaper,adiscrete-timeanalysisofthethird-ordercharge-pumpbasedphase-lockedloops(CPLLs)ispresentedinthepresenceofloopdelay.Thez-domainanalysisoftheclosed-looptransferfunctionisderivedandcomparedwiththetraditionals-domainmethod.ThesimulationresultsunderSPECTREshowthat,duetothesamplingnatureofCPLL,thetraditionals-domainanalysisisunabletopredictitsjitterpeakingaccurately,especiallywhentheloopdelayistakenintoconsideration.Theimpactofloopdelayonthestabilityofthethird-orderCPLLsystemisfurtheranalyzedbasedontheproposedway.ThestabilitylimitofthewidebandwidthCPLLwithloopdelayiscalculated.Thecircuitsimulationresultsagreewellwithmathematicalanalysis.

  • 标签: charge-pump based phase-locked LOOP (CPLL) THIRD-ORDER
  • 简介:在这份报纸,有概率的变化时间的延期的Lurie控制系统的绝对稳定性被学习。由使用新扩大Lyapunov-Krasovskii功能,一个改进稳定性标准比那些介绍结果的基于LMI被介绍,它的解决之可能性重重地取决于延期范围和它的衍生物的尺寸,它有更宽的应用程序领域。效率和介绍结果的减少的保守主义能被二个数字例子与给一些比较结果表明。

  • 标签: 稳定性判据 时变时滞 概率区间 LURIE系统 LYAPUNOV-KRASOVSKII泛函 时滞相关
  • 简介:延期依赖者H无穷分析;为连续时间延期系统的H无穷控制问题被学习。由与一些免费weighting矩阵介绍平等,有为如此的系统的H无穷性能的延期依赖者稳定性的一个改进标准被介绍,;存在的一个标准;为如此的系统的延期依赖者H无穷控制器的一些设计方法以一套矩阵不平等被建议,它被一个反复的算法高效地解决。进一步,延期依赖者的相应结果柔韧的H无穷分析;柔韧的H无穷为不明确的系统被给的连续时间延期控制问题。最后,二个数字例子被给由与另外的存在结果作比较说明建议方法的效率。

  • 标签: H∞控制 连续时滞系统 状态反馈 自动控制理论
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