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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

Assessing human sperm morphology： top models, underdogs or biometrics？

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Asian Journal of Andrology 2010年第1期12卷 36-46页

作者： Jacques auger Service d＇Histologie-Embryologie Biologie de la Reproduction/CECOS Hopital Cochin Paris 75014 France

The assessment of the percentage of spermatozoa having an ＇ideal＇ morphology using so-called strict method is the method recommended in the latest edition of the World Health Organization （WHO） laboratory manual for semen analysis. This recommendation is a result of the statistical association between ＇ideal＇ sperm morphology and fertility, and of the current general belief that sperm morphology assessment should be used primarily as a fertility tool. The notion of an ＇ideal＇ sperm morphology has persisted despite the very low percentage of such spermatozoa in the semen of fertile men, a subject of intense controversy. The detailed categorization of each abnormal spermatozoon has thus, for a long time, been considered optional and partially redundant, an idea which is reflected in the earlier editions of the WHO manual. However, several recent studies have shown the importance of carefully assessing abnormal sperm morphology for use in the diagnosis ＆infertility, to determine fertility prognosis, and for basic or public health studies. One approach, which combines videomicroscopy and computer vision, and is the only approach able to assess the continuum of sperm biometrics, has been used successfully in several recent clinical, basic and toxicology studies. In summary, the visual assessment of detailed sperm morphology--including the categorization of anomalies allowing arithmetically derived indices of teratozoospermia--and the more modern computer-based approaches, although often considered to be redundant, are in fact complementary. The choice of the most appropriate method depends on the field of investigation （clinical, research, toxicology） and the problem being addressed. Each approach has advantages as well as certain limitations, which will be discussed briefly herein.

关键词： diagnosis fertility prognosis image analysis multiple anomalies index pattern recognition reproductive toxicology spermdefects sperm deformity index sperm pathology teratozoospermic index videomicroscopy

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

Seed wasp invasions promoted by unregulated seed trade affect vegetal and animal biodiversity

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Integrative Zoology 2012年第3期7卷 228-246页

作者： Marie-Anne auger-ROZENBERg Alain ROQUES French National Institute for Agricultural Research(INRA) Forest Ecology(UR633)OrleansFrance

Cone and seed insects are considered the most important predators of tree seeds during the pre-dispersal phase of *** them,exotic seed chalcids in the genus Megastigmus invaded Europe as a result of the rapidly-increasing and mostly unregulated seed trade for afforestation and ornamental *** their economic impact in seed orchards,until recently,little attention was paid to the ecological impact of these *** the present study,selected case studies of alien Megastigmus *** considered to assess their specific impact on the potential of natural regeneration of native woody plants and on the native entomofauna competing for seed *** re-analyzed data from former studies that did not focus on these ecological interactions and,here,present previously unpublished *** of Douglas-fir,true cedars,true firs and wild roses were sampled all over Europe,and the relative importance of the native and invasive chalcid species was assessed as well as their specific impact on seed *** most cases,the recent arrival of alien chalcids resulted in a significant decrease in the regeneration potential of the host *** the absence of competitors,alien chalcids occupied the entire seed niche in Douglas-fir,but their impact tended to decrease after the arrival of invasive seed *** firs,alien chalcids tended to displace the native chalcids,but not in wild roses and cedars,where their damage was *** biological traits that might explain invasive success of alien chalcids are ***,no general invasive patterns seem to exist.

关键词： ecological impact invasion Megastigmus seed trade

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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Xiamen after 20 Years of Ecological Transformation

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China Today 2025年第1期74卷 66-68页

作者： ZACHARY g.LUNDQUIST 不详

The efforts Xiamen has made in ecological protection over the last 20 years have helped it become a beautiful and clean *** years ago,I had the opportunity to travel to the city of Xiamen in southeastern China’s Fujian ***,due to the fact that I was in a rush,I did not have the chance to see the whole *** memory of Xiamen was its pleasant climate and unforgettable beauty-I knew if I ever got the opportunity,I would revisit this *** years went by until I was able to return to this city *** emerging from the airport,I realized that I had grown older,while Xiamen was becoming increasingly youthful and *** exactly had given this city such vitality?

关键词： Ecological Xiamen Transformation

On the origin of the high tensile strength and ductility of additively manufactured 316L stainless steel: Multiscale investigation

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Journal of Materials Science & Technology 2020年第6期41卷 209-218页

作者： Bassem Barkia Pascal Aubry Paul Haghi-Ashtiani Thierry auger Lionel gosmain Frédéric Schuster Hicham Maskrot DEN-Service d’Etudes Analytiques et de Réactivitédes Surfaces CEAUniversitéParis-Saclay91191France Laboratoire de Mécanique des Sols Structures et MatériauxCentralesupélecUMR CNRS 8579UniversitéParis-Saclay92295France Arts et Métiers ParisTech PIMMUMR CNRS 800675013 ParisFrance CEA Cross-Cutting Program on Materials and Processes Skills 91191Gif-sur-YvetteFrance

We report that 316L austenitic stainless steel fabricated by direct laser deposition(DLD),an additive manufacturing(AM)process,have a higher yield strength than that of conventional 316L while keeping high *** interestingly,no clear anisotropy in tensile properties was observed between the building and the scanning direction of the 3D printed *** examination of the as-built parts shows a heterogeneous solidification cellular *** electron microscopy observations coupled with Energy Dispersive X-ray Spectrometry(EDS)reveal the presence of chemical micro-segregation correlated with high dislocation density at cell boundaries as well as the in-situ formation of well-dispersed oxides and transition-metal-rich *** hierarchical heterogeneous microstructure in the AM parts induces excellent strength of the 316L stainless steel while the low staking fault energy of the as-built 316L promotes the occurrence of abundant deformation twinning,in the origin of the high ductility of the AM *** additional post-process treatments,the AM 316L proves that it can be used as a structural material or component for repair in mechanical construction.

关键词： Additive manufacturing Austenitic stainless steel Dislocation structure Twinning Mechanical behavior Anisotropy