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Stepping up after spinal cord injury:negotiating.a. 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.a.e 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

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.a.d 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.a.d 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)

Macroscopic Studies on the Properties of the Anodic Oxide Films on Titanium

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Journal of Materials Science & Technology 1998年第3期14卷 241-246页

作者： Mahdy, g.a. Mahmoud, S.S. Chemistry Dept. Faculty of Science Helwan University Helwan Cairo Egypt Chemistry Dept. University College for Women Ain-Shams University Helopolis Cairo Egypt

The effect of fluoride ions on the formation and dissolution behaviour of anodic oxide films on Ti has been investigated in acidic fluoride media (pH=1) using impedance and galvanostatic techniques. A5 the fluoride ion concentration and temperature increase the rate of oxide film formation decreases while the dissolution process increases. oxide film formed at high tem-perature and formation voltage was found to contain more defect sites in the film than that formed at a lower one. Activation energies are calculated during the oxide film formation and dissolution and found to be 20.76 and 28.72 kJ/mol, respectively. Formation rate and reciprocal capacitance data are reported as a function of polarizing current density. Values are recorded for the electrolytic parameters A and B. Potentiostatic curves are derived from the galvanostatic results.

关键词： Figure Macroscopic Studies on the Properties of the Anodic Oxide Films on Titanium

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.a.d cerebral perfusion.

关键词： cerebral perfusion electronic

Residuated Completely Simple Semigroups

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Algebra Colloquium 2014年第2期21卷 181-194页

作者： T.S. Blyth g.a. Pinto Mathematical Institute University of St Andrews Scotland Instituto Piaget Campus Universitario de Almada Quinta da Arreinela de Cima 2800-305 Almada Portugal Universidade Atlantica Instituto de Investigagao Cientifica e Tecnologica Fabrica da Polvora 2730-036 Barcarena Portugal

We consider particular compatible orders on a given completely simple semi- group Sx= M（（x）; I, A; P） where （x） is an ordered cyclic group with x 〉 1 and p11= x-1. Of these, only the lexicog.a.hic and bootlace orders yield residuated semigroups. With the lexicog.a.hic order, Sx is orthodox and has a biggest idempotent. With the bootlace order, the maximal idempotents of Sx are identified by specific locations in the sandwich matrix. In the orthodox case there is also a biggest idempotent and, for sandwich matrices of a given size, uniqueness up to ordered semigroup isomorphism is established.

关键词： lexicog.a.hic order bootlace order residuated completely simple semigroup

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

Assessment of deterioration in RHA-concrete due to magnesium sulphate attack

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 691-696页

作者： g.a. Habeeb H.B. Mahmud N.B.A.A. Hamid Department of Civil Engineering Faculty of Engineering University of Malaya

The assessment of magnesium sulphate attack on concretes containing rice husk ash （RHA, 20wt% of the cementitious materials） with various average particle sizes was investigated. The total cementitious materials were 390 kg.a.d the water-to-binder ratio （W/B） was 0.53 for all mixtures. Specimens were initially cured in water for 7 d and then immersed in the 3wt% magnesium sulphate solution for up to 111 d of exposure. The specimens were subjected to drying-wetting cycles to accelerate sulphate attack. In addition to the visual monitoring of the specimens, the concrete specimens were subsequently tested for compressive strength, dynamic modulus of elasticity, and length and mass changes. The results show that the specimens exposed to sulphate attack exhibit higher strength and dynamic modulus than those kept in water. The length change is negligible and can be attributed to the normal swelling of concrete. On the other hand, concretes suffers mass loss and surface spalling.a.d softening; the fine RHA-concrete results in a better resistance. For the accelerated sulphate attack method used in this study, mass change and visual monitoring.a.e recommended for assessing the deterioration degree and the effectiveness of supplementary cementitious materials to resist sulphate attack.

关键词： concretes pozzolan ettringite rice husk ash (RHA) magnesium sulphate

geochemistry and petrogenetic evolution of metasedimentary rocks in Bunu Area,part of Kabba-Lokoja-Igarra schist belt,SW Nigeria

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Acta geochimica 2022年第5期41卷 765-788页

作者： M.S.Kolawole E.C.chukwu A.N.Agibe Department of geology Federal UniversityOye-EkitiEkiti StateNigeria

Field and geochemical studies of the Bunu area,SW Nigeria,were carried out on gneiss-metasedimentary rocks that consist of mig.a.ised gneiss,quartz-mica schist,and foliated and massive *** gneissmetasedimentary rocks are interbedded with meta-igneous rock(amphibolite),all of which are intruded by g.a.itoid and cut by basic and felsic *** data on major,trace,and rare Earth elements of these rocks from the area were used to speculate on the petrogenetic and geodynamic evolution of the rocks in the ***,the metasedimentary rocks in the area have a restricted range of major oxides such as SiO_(2)and Al_(2)O_(3)with low average values of FeO,MnO,CaO,and *** of average values of HSFE such as Zr,Nb,and Y are moderately high in mig.a.itic gneiss,quartzmica schist,and low in both massive and foliated quartzite.ΣLREE average values are 124.25,132.41,and18.64 ppm respectively for mig.a.ite gneiss,quartz-mica schist,and low in both massive and foliated *** rocks are also generally enriched in Ba,Cs,Pb,U,Cr,Rb,and Zr and depleted in Be,Sr,Ti,Mo,Th,and *** enrichment–depletion in major oxides and trace elements of the rocks in this area is probably a consequence of the movement of metamorphic remobilized fluids within the rocks in the area during the Pan-African or earlier events as noted in the adjacent Egbe-Isanlu Schist belt.A further geochemical characterisation of the rocks in the area using Log(Na_(2)O/KO)vs Log(SiO_(2)/Al_(2)O_(3)indicates that while the protolith of mig.a.ised gneiss and quartzmica schist are greywackes to litharenite in compositions that of quartzites are sublitharenite to quartz *** the ternary plot of Al_(2)O_(3)-(CaO+Na_(2)O)-KO for metasedimentary rocks in the area,most mig.a.itic gneiss and quartz-mica schist rocks plot close to average shale while quartzites mostly tend to illite compositions and almost toward the Al_(2)O_(3)-apex of the diag.a. attesting to depletion of

关键词： geochemical studies Metasedimentary rocks geodynamic activities Protolith Passive continental margins

STUDY OF RAY IRRADIATION ON DIAMOND-LIKE CARBON FILMS

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 26-32页

作者： g.a. Liu T.M. Wang E.Q Dept. of Appl. Phy. Southwest Jiaotong Univ. Chengdu 610031 China

Diamond-like carbon (DLC) films have been deposited on g.a.s substrates using.a.io-frequency (rf) plasma deposition method. gamma -ray, ultraviolet (UV) ray were used toirradiate the DLC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe changing characteristics of SP^3 C-H bond and hydrogen content in the films due to theirradiations. The results show that, the damage degrees induced by the UV ray on the SP^3 C-H bondsare much stronger than that by the gamma -ray. When the irradiation dose of gamma -ray reaches 1 OX10^4 gy, the SP^3 C-H bond reduces about 50 percent in number. The square electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using the results on optical gap of the films and the fully constrained network theory,the hydrogen content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film gamma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance