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Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

Small mammal community composition impacts bank vole (Clethrionomys glareolus) population dynamics and associated seroprevalence of Puumala orthohantavirus

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Integrative Zoology 2024年第1期19卷 52-65页

作者： Felicitas Maria BUJNOCH Daniela REIL Stephan DREWES Ulrike MROSENFELD rainer.g.ulrich Jens JACOB Christian IMHOLT Julius Kühn-Institute Federal Research Centre for Cultivated PlantsInstitute for Epidemiology and Pathogen DiagnosticsRodent ResearchMünsterGermany University of Münster Institute for Evolution and BiodiversityMünsterGermany Friedrich-Loeffler-Institut Federal Research Institute for Animal HealthInstitute of Novel and Emerging Infectious DiseasesGreifswald-Insel RiemsGermany

Rodents are important reservoirs for zoonotic pathogens that cause diseases in *** is hypoth-esized to be closely related to pathogen prevalence through multiple direct and indirect *** example,the presence of non-host species can reduce contact rates of the main reservoir host and thus reduce the risk of transmission(“dilution effect”).In addition,an overlap in ecological niches between two species could lead to increased interspecific competition,potentially limiting host densities and reducing density-dependent pathogen transmission *** this study,we investigated the relative impact of population-level regulation of direct and indirect drivers of the prevalence of Puumala orthohantavirus(PUUV)in bank voles(Clethrionomys glareolus)during years with high *** compiled data on small mammal community composition from four regions in germany between 2010 and *** equation modeling revealed a strong seasonality in PUUV control mechanisms in bank *** abundance of shrews tended to have a negative relationship with host abundance,and host abundance positively influenced PUUV seroprevalence,while at the same time increasing the abundance of competing non-hosts like the wood mouse(Apodemus sylvaticus)and the yellow-neckedfield mouse(Apodemusflavicollis)were associated with reduced PUUV seroprevalence in the *** results indicate that for PUUV in bank voles,dilution is associated with increased interspecific *** pressures leading to the decline of Apodemus *** a specific habitat could lead to the amplification of mechanisms promoting PUUV transmission within the host populations.

关键词： bank vole biodiversity Puumala orthohantavirus small mammals

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan Li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may exacerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to explore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

Impact of Zika virus non-structural protein mutations on hippocampal damage

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Neural Regeneration Research 2025年第8期20卷 2307-2308页

作者： Larissa M.g.Cassiano Roney S.Coimbra Neurogenômica/Imunopatologia Instituto RenéRachouFiocruzBelo HorizonteBrazil Departamento de Bioquímica e Imunologia Instituto de Ciências BiológicasUniversidade Federal de Minas GeraisBelo HorizonteBrazil

The Zika virus(ZIKV),a member of the Flaviviridae family,attracted worldwide attention for its connection to severe neurological effects,notably microcephaly in newborns,first reported during the 2015 epidemic in ***,its impact goes beyond fetal and neonatal abnormalities,also affecting the central nervous system(CNS)in both children and adults,leading to enduring cognitive and behavioral impairments.

关键词： damage fetal neonatal

Projective Hilbert modules and sequential approximations

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Science China Mathematics 2025年第1期 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue University Department of Mathematics East China Normal University Department of Mathematics University of Oregon Shanghai Institute for Mathematics and Interdisciplinary Sciences

We show that when A is a separable C*-algebra,every countably generated Hilbert A-module is projective（with bounded module maps as morphisms）.We also study the approximate extensions of bounded module *** the case where A is a σ-unital simple C*-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

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Molecular Dynamics Study of a Thermal Expansion Coefficient： Ti Bulk with an Elastic Minimum image Method

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Chinese Physics Letters 2006年第5期23卷 1068-1071页

作者： Yakup Hundur rainer Hippler Ziya B. güven Department of Physics Istanbul Technical University Ayazaga Istanbul TR-34469 Turkey Institut für Physik Ernst-Moritz-Arndt-Universitat Greifswald DomstraBe 10a D-17487 Greifswald. Germany Electronic and Communication Engineering Cankaya University Balgat Ankara TR-06530 Turkey

Linear thermal expansion coefficient （TEC） of Ti bulk is investigated by means of molecular dynamics simulation. The elastic minimum image convention of periodic boundary conditions is introduced to allow the bulk to adjust its size according to the new fixed temperature. The TEC and the specific heat of Ti are compared to the available theoretical and experimental data.

关键词： TITANIUM

Comparison of ligand migration and binding in heme proteins of the globin family

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Chinese Physics B 2015年第12期24卷 109-118页

作者： Karin Nienhaus g.ulrich Nienhaus Institute of Applied Physics (APH) Karlsruhe Institute of Technology (KIT) Institute of Nanotechnology (INT) and Institute of Toxicology and genetics (ITg) Karlsruhe Institute of Technology (KIT) Department of Physics University of Illinois at Urbana-Champaign

The binding of small diatomic ligands such as carbon monoxide or dioxygen to heme proteins is among the simplest biological processes known. Still, it has taken many decades to understand the mechanistic aspects of this process in full detail. Here, we compare ligand binding in three heme proteins of the globin family, myoglobin, a dimeric hemoglobin, and neuroglobin. The combination of structural, spectroscopic, and kinetic experiments over many years by many laboratories has revealed common properties of globins and a clear mechanistic picture of ligand binding at the molecular level. In addition to the ligand binding site at the heme iron, a primary ligand docking site exists that ensures efficient ligand binding to and release from the heme iron. Additional, secondary docking sites can greatly facilitate ligand escape after its dissociation from the heme. Although there is only indirect evidence at present, a preformed histidine gate appears to exist that allows ligand entry to and exit from the active site. The importance of these features can be assessed by studies involving modified proteins（via site-directed mutagenesis） and comparison with heme proteins not belonging to the globin family.

关键词： flash photolysis ligand binding time-resolved spectroscopy heme protein

Friction between a temperature dependent viscoelastic body and a rough surface

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Friction 2016年第1期4卷 50-64页

作者： rainer HEISE Institute for Mechanics Technische Universit(a)t Berlin Straβe des 17.Juni 135 Berlin D-10623 Germany

In this study, we investigate the friction between a one-dimensional elastomer and a one-dimensional rigid randomly rough surface. Special emphasis is laid on the temperature dependence of the elastomer and its effect on the frictional behavior of the contact. The elastomer is modeled as a Kelvin body in a one-dimensional substitute model in the spirit of the method of dimensionality reduction. The randomly rough surface is a self-affine one-dimensional fractal. We provide a short discussion of a conical indenter pressed in a displacement controlled process into an elastomer. These analytical considerations are taken as a basis for the treatment of the randomly rough counter surface in contact to an elastomer with and without temperature dependent viscosity. We identify dimensionless quantities describing this process, introduce a thermal length scale, and give estimates for the coefficient of friction as function of velocity, indentation and thermal quantities.

关键词： elastomer friction temperature dependence coefficient of friction