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The Large Scale Instability in Rotating Fluid with Small Scale Force

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Open Journal of Fluid Dynamics 2015年第2期5卷 128-138页

作者： michael kopp Anatoly Tur Vladimir Yanovsky National Academy of Science Ukraine Institute for Single Crystals Kharkiv University Kharkov Ukraine Institut de Recherche en Astrophysique et Planétologie CNRS Université de Toulouse [UPS] Toulouse France

In this paper, we find a new large scale instability in rotating flow forced turbulence. The turbulence is generated by a small scale external force at low Reynolds number. The theory is built on the rigorous asymptotic method of multi-scale development. The nonlinear equations for the instability are obtained at the third order of the perturbation theory. In this article, we explain the nonlinear stage of the instability and the generation vortex kinks.

关键词： Large Scale Vortex Instability Coriolis Force Multi-Scale Development Small Scale Turbulence Vortex Kinks

Nonlinear Vortex Structures in Obliquely Rotating Fluid

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Open Journal of Fluid Dynamics 2015年第4期5卷 311-321页

作者： michael kopp Anatoly Tur Vladimir Yanovsky Institute for Single Crystals National Academy of Sciences of Ukraine Kharkov Ukraine V.N. Karazin Kharkiv National University 4 Svobody Sq. Kharkov Ukraine Université de Toulouse [UPS] CNRS Institut de Recherche en Astrophysique et Planétologie Toulouse Cedex France

In this paper, we find a new large scale instability which appears in obliquely rotating flow with the small scale turbulence, generated by external force with small Reynolds number. The external force has no helicity. The theory is based on the rigorous method of multi-scale asymptotic expansion. Nonlinear equations for instability are obtained in the third order of the perturbation theory. In this article, we explain in detail the nonlinear stage of the instability and we find the nonlinear periodic vortices and the vortex kinks of Beltrami type.

关键词： Large Scale Vortex Instability Coriolis Force Multi-Scale Asymptotic Development Small Scale Turbulence Vortex Kinks

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Desiro ML系族动车组平台

国外内燃机车 2009年第2期 9-15页

作者： michael kopp 韩才元

Desiro ML系族动车组平台是根据城市铁路、地区铁路和地区间铁路运输的市场需求情况而开发的,该平台适合电力动车组和内燃动车组。这些动车组具有高的编组灵活性,其中间拖车的数量可以随客流量的变化而配置。现代拖车的旅客间采用模块... 详细信息

Desiro ML系族动车组平台是根据城市铁路、地区铁路和地区间铁路运输的市场需求情况而开发的,该平台适合电力动车组和内燃动车组。这些动车组具有高的编组灵活性,其中间拖车的数量可以随客流量的变化而配置。现代拖车的旅客间采用模块化设计,乘客座位数量可以设置120～400个。文中介绍了平台设计的优点和具有蓄能器的Desiro ML系族动车组平台设计的理念;描述了该动车组的技术参数、总体结构和各部分及子系统的设计。

关键词：动车组平台内燃动车组电力动车组平台设计结构技术参数

A robust new metric of phenotypic distance to estimate and compare multiple trait differences among populations

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Current Zoology 2012年第3期58卷 426-439页

作者： Rebecca SAFRAN Samuel FLAXMAN michael kopp Darren E. IRWIN Derek BRIGGS Matthew R. EVANS W. Chris FUNK David A. GRAY Eileen A. HEBETS Nathalie SEDDON Elizabeth SCORDATO Laurel B. SYMES Joseph A. TOBIAS David P. L. TOEWS J. Albert C. UY Department of Ecology and Evolutionary Biology University of Colorado Boulder CO 80309 U.S.A. Mathematics and B iosciences Group Faculty of Mathematics University of Vienna A-1090 Vienna Austria Current address Evolutionary Biology and Modeling Group Faculty of Sciences Aix-Marseille University 13331 Marseille France. Department of Zoology University of British Columbia 6270 University Boulevard Vancouver BC Canada V6T 1Z4. Research ＆ Evaluation Methodology School of Education University of Colorado Boulder CO 80309 U.S.A. School of Biological and Chemical Sciences Queen Mary University of London London E1 4NS Department of Biology Colorado State University Fort Collins CO 80523 U.S.A. Department of Biology California State University Northridge CA 91330 U.S.A. School of Biological Sciences University of Nebraska Lincoln NE 68588 U.S.A. Edward Grey Institute Department of Zoology University of Oxford Oxford OX1 3PS UK Committee on Evolutionary Biology The University of Chicago Chicago IL 60637U.S.A. Department of Biology Dartmouth College Hanover NH 03755 U.S.A. Department of Biology University of Miami Coral Gables FL 33146 U.S.A.

Whereas a rich literature exists for estimating population genetic divergence, metrics of phenotypic trait divergence are lacking, particularly for comparing multiple traits among three or more populations. Here, we review and analyze via simula- tion Hedges＇ g, a widely used parametric estimate of effect size. Our analyses indicate that g is sensitive to a combination of unequal trait variances and unequal sample sizes among populations and to changes in the scale of measurement. We then go on to derive and explain a new, non-parametric distance measure, ＇Aft＇, which is caiculated based upon a joint cumulative distribution function （CDF） from all populations under study. More precisely, distances are measured in terms of the percentiles in this CDF at which each population＇s median lies. Ap combines many desirable features of other distance metrics into a single metric; namely, compared to other metrics, p is relatively insensitive to unequal variances and sample sizes among the populations sam- pied. Furthermore, a key feature of Ap--and our main motivation for developing it--is that it easily accommodates simultaneous comparisons of any number of traits across any number of populations. To exemplify its utility, we employ Ap to address a ques- tion related to the role of sexual selection in speciation： are sexual signals more divergent than ecological traits in closely related taxa？ Using traits of known function in closely related populations, we show that traits predictive of reproductive performance are indeed, more divergent and more sexually dimorphic than traits related to ecological adaptation [Current Zoology 58 （3）： 426-439 2012].

关键词： Effect size Phenotype divergence Sexual dimorphism Sexual selection Speciation

Movement analysis in the diagnosis and management of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 485-486页

作者： Johannes Burtscher Nicolas Bourdillon Jules MJanssen Daalen Aurélien Patoz Julien FBally Martin kopp Davide Malatesta Bastiaan RBloem Institute of Sport Sciences University of LausanneLausanneSwitzerland Radboud University Medical Center Department of NeurologyDonders Institute for BrainCognition and BehaviorCenter of Expertise for Parkinson and Movement DisordersNijmegenThe Netherlands Radboud University Medical Center Department of Medical BioSciencesNijmegenThe Netherlands Research and Development Department Volodalen Swiss Sport LabAigleSwitzerland Service of Neurology Department of Clinical NeurosciencesLausanne University Hospital(CHUV)and University of Lausanne(UNIL)LausanneSwitzerland Department of Sport Science University of InnsbruckInnsbruckAustria

Challenges in the diagnosis and treatment of Parkinson’s disease:Parkinson’s disease(PD)is an increasingly prevalent neurodegenerative disease,at first sight primarily characterized by motor symptoms,although non-motor symptoms also constitute a major part of the overall ***,this disease cannot be diagnosed reliably until a large part of the vulnerable dopaminergic neurons has been irretrievably lost,and the disease progresses *** biological criteria for PD have been proposed recently and might eventually improve early diagnosis,but they require further validation,and their use will initially be restricted to a research environment(Darweesh et al.,2024).

关键词： diagnosis Clinical eventually

Like a G6-nal:transcriptional control of G-protein coupled receptors during oligodendroglial development

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Neural Regeneration Research 2025年第7期20卷 2001-2002页

作者： Tim Aberle michael Wegner Institut für Biochemie Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany

Multilayered control of myelination:Quick,saltatory conduction of action potentials along nerve fibers requires the electrical insulation of axons by myelinating *** the central nervous system,this role is taken up by *** are marked by the expression of the lineage determinants Sox10 and Olig2 and arise from oligodendrocyte precursor cells(OPCs)during embryonal *** the majority of OPCs differentiate into mature oligodendrocytes when nearby axonal segments require myelination,a small subpopulation of OPCs persist as a progenitor ***,the timing of myelination and maintenance of the OPC pool both need to be precisely *** transcription factors either positively or negatively affect oligodendrocyte differentiation and maintenance of the OPC pool as components of a complex gene regulatory network(reviewed in Sock and Wegner,2021).Network activity is additionally influenced by extracellular signaling molecules that bind to receptors on the oligodendroglial cell surface and activate intracellular signaling *** the receptors are linked to the network is poorly understood so far,but pivotal to understanding the overall regulation of central nervous system(CNS)myelination in response to environmental *** insights were recently gained for Gpr37(Schmidt et al.,2024),a G-protein coupled receptor(GPCR)with known relevance in differentiating oligodendrocytes(Yang et al,2016).

关键词： gained insulation conduction

Emerging structures and dynamic mechanisms ofγ-secretase for Alzheimer’s disease

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Neural Regeneration Research 2025年第1期20卷 174-180页

作者： Yinglong Miao michael S.Wolfe Computational Medicine Program and Department of Pharmacology University of North Carolina–Chapel HillChapel HillNCUSA Department of Medicinal Chemistry University of KansasLawrenceKSUSA

γ-Secretase,called“the proteasome of the membrane,”is a membrane-embedded protease complex that cleaves 150+peptide substrates with central roles in biology and medicine,including amyloid precursor protein and the Notch family of cell-surface *** inγ-secretase and amyloid precursor protein lead to early-onset familial Alzheimer’s disease.γ-Secretase has thus served as a critical drug target for treating familial Alzheimer’s disease and the more common late-onset Alzheimer’s disease as ***,critical gaps remain in understanding the mechanisms of processive proteolysis of substrates,the effects of familial Alzheimer’s disease mutations,and allosteric modulation of substrate cleavage byγ-*** this review,we focus on recent studies of structural dynamic mechanisms ofγ-*** mechanisms,including the“Fit-Stay-Trim,”“Sliding-Unwinding,”and“Tilting-Unwinding,”have been proposed for substrate proteolysis of amyloid precursor protein byγ-secretase based on all-atom molecular dynamics *** an incorrect registry of the Notch1 substrate was identified in the cryo-electron microscopy structure of Notch1-boundγ-secretase,molecular dynamics simulations on a resolved model of Notch1-boundγ-secretase that was reconstructed using the amyloid precursor protein-boundγ-secretase as a template successfully capturedγ-secretase activation for proper cleavages of both wildtype and mutant Notch,being consistent with biochemical experimental *** approach could be potentially applied to decipher the processing mechanisms of various substrates byγ-*** addition,controversy over the effects of familial Alzheimer’s disease mutations,particularly the issue of whether they stabilize or destabilizeγ-secretase-substrate complexes,is ***,an outlook is provided for future studies ofγ-secretase,including pathways of substrate binding and product release,effects of modulators on familial Alzheimer’s disease mutations

关键词： Alzheimer’s disease amyloid precursor protein cryo-EM structures drug design intramembrane proteolysis molecular dynamics Notch

NECAB family of neuronal calcium-binding proteins in health and disease

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Neural Regeneration Research 2025年第5期20卷 1236-1243页

作者： Diones Bueno michael K.E.Schafer Sudena Wang michael J.Schmeisser Axel Methner Institute for Molecular Medicine University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Department of Anesthesiology University Medical Center of the Johannes Gutenberg-UniversityMainzGermany Institute of Anatomy University Medical Center of the Johannes Gutenberg-UniversityMainzGermany

The N-terminal EF-hand calcium-binding proteins 1–3(NECAB1–3) constitute a family of predominantly neuronal proteins characterized by the presence of at least one EF-hand calcium-binding domain and a functionally less well characterized C-terminal antibiotic biosynthesis monooxygenase domain. All three family members were initially discovered due to their interactions with other proteins. NECAB1 associates with synaptotagmin-1, a critical neuronal protein involved in membrane trafficking and synaptic vesicle exocytosis. NECAB2 interacts with predominantly striatal G-protein-coupled receptors, while NECAB3 partners with amyloid-β A4 precursor protein-binding family A members 2 and 3, key regulators of amyloid-β production. This demonstrates the capacity of the family for interactions with various classes of proteins. NECAB proteins exhibit distinct subcellular localizations: NECAB1 is found in the nucleus and cytosol, NECAB2 resides in endosomes and the plasma membrane, and NECAB3 is present in the endoplasmic reticulum and Golgi apparatus. The antibiotic biosynthesis monooxygenase domain, an evolutionarily ancient component, is akin to atypical heme oxygenases in prokaryotes but is not wellcharacterized in vertebrates. Prokaryotic antibiotic biosynthesis monooxygenase domains typically form dimers, suggesting that calcium-mediated conformational changes in NECAB proteins may induce antibiotic biosynthesis monooxygenase domain dimerization, potentially activating some enzymatic properties. However, the substrate for this enzymatic activity remains uncertain. Alternatively, calcium-mediated conformational changes might influence protein interactions or the subcellular localization of NECAB proteins by controlling the availability of protein–protein interaction domains situated between the EF hands and the antibiotic biosynthesis monooxygenase domain. This review summarizes what is known about genomic organization, tissue expression, intracellular localization, interac

关键词： calcium EF hand mitochondria nervous system signal transduction

Small extracellular vesicles derived from cerebral endothelial cells with elevated microRNA 27a promote ischemic stroke recovery

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Neural Regeneration Research 2025年第1期20卷 224-233页

作者： Yi Zhang Zhongwu Liu michael Chopp michael Millman Yanfeng Li Pasquale Cepparulo Amy Kemper Chao Li Li Zhang Zheng Gang Zhang Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA Department of Pathology Henry Ford HospitalDetroitMIUSA Division of Pharmacology Department of NeuroscienceReproductive and Dentistry SciencesSchool of MedicineUniversity of Naples“Federico Ⅱ”NaplesItaly

Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional *** previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endothelial cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic *** the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression *** EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a *** male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or *** array of behavior assays was used to measure neurological *** with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological *** vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal *** analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct *** of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of *** data provide evidence that 27a-sEVs have

关键词： axonal remodeling cerebral endothelial cells exosomes miR-27a mitochondria Semaphorin 6A small extracellular vesicles stroke