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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)

The paternal epigenome and embryogenesis： poising mechanisms for development

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Asian Journal of Andrology 2011年第1期13卷 76-80页

作者： Timothy g jenkins douglas T Carrell Andrology and IVF Laboratories Department of Surgery University of Utah Salt Lake City UT 84108 USA department of Obstetrics and gynecology University of Utah School of Medicine Salt Lake City UT 84108 USA department of Physiology University of Utah School of Medicine Salt Lake City UT 84108 USA

The scope of paternal contributions during early embryonic development has long been considered limited. dramatic changes in chromatin structure throughout spermatogenesis have been thought to leave the sperm void of complex layers of epigenetic regulation over the dNA blueprint, thus leaving the balance of that regulation to the oocyte. However, recent work in the fields of epigenetics and male factor infertility has placed this long-held, and now controversial dogma, in a new light. Elegant studies investigating chromatin and epigenetic modifications in the developing sperm cell have provided new insights that may establish a more critical role for the paternal epigenome in the developing embryo. dNA methylation, histone tail modifications, targeted histone retention and protamine incorporation into the chromatin have great influence in the developing sperm cell. Perturbations in the establishment and/or maintenance of any of these epigenetic marks have been demonstrated to affect fertility status, ranging in severity from mild to catastrophic. Sperm require this myriad of chromatin structural changes not only to serve a protective role to dNA throughout spermatogenesis and future delivery to the egg, but also, it appears, to contribute to the developmental program of the future embryo. This review will focus on our current understanding of the epigenetics of sperm. We will discuss sperm-specific chromatin modifications that result in genes essential to development being poised for activation early in embryonic development, the disruption of which may result in reduced fecundity.

关键词： chromatin dNA methylation embryogenesis epigenetics histone modification male infertility

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质子发射核151Lu的衰变研究

质子发射核151Lu的衰变研究

Interaction of Waves, Surface Currents, and Turbulence: the Application of Surface-Following Coordinate Systems

第十五届全国核结构大会

作者： F.Wang B.Sun Z.Liu C.Scholey S.F.Ashley L.Bianco d.M.Cullen I.J.Cullen I.g.darby S.Eeckhaudt A.B.garnsworthyand W.gelletly M.B.gomez-Hornillos T.grahn P.T.greenlees d.g.jenkins g.A.Jones P.Jones d.T.Joss R.Julin S.Juutinen S.Kettelhut S.Khan A.Kishada M.Leino M.Niikura M.Nyman R.d.Page J.Pakarinen S.Pietri Z.Podolyak P.Rahkila S.Rigby J.Saren T.Shizuma J.Simpson J.Sorri S.Steer N.J.Thompson J.Uusitalo P.M.Walker S.Williams School of Physics and Nuclear Energy Engineering Beihang University Institute of Modern Physics Chinese Academy of Sciences department of Physics University of Surrey Guildford Surrey GU2 7XH UK department of Physics University of JyvaskylaJyvaskyla FI-40014 Finland department of Physics University of Manchester Manchester M13 9PL UK

质子发射核为研究质子滴线附近的核结构提供了重要信息[1]。1981年,在德国gSI的SHIP的速度选择器上,发现了第一个基态质子发射核151Lu。近期又发现151Lu存在一个短寿命的低自旋同核异能态。基于WKB和dWBA理论,简单估计球形核的h11/2和d...

质子发射核为研究质子滴线附近的核结构提供了重要信息[1]。1981年,在德国gSI的SHIP的速度选择器上,发现了第一个基态质子发射核151Lu。近期又发现151Lu存在一个短寿命的低自旋同核异能态。基于WKB和dWBA理论,简单估计球形核的h11/2和d3/2带,可以得到基态为Ep=1223ke V,t1/2=280ms以及同核异能态Ep=1310ke V,t1/2=16μs[2-4]。151Lu激发态的首次跃迁测量是在橡树

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Journal of Ocean University of China 2007年第4期6卷 319-331页

作者： jenkins Alastair d Bjerknes Centre for Climate Research Geophysical Institute Allegaten 70 N-5007 Bergen Norway

Surface waves comprise an important aspect of the interaction between the atmosphere and the ocean, so a dynamically consistent framework for modelling atmosphere-ocean interaction must take account of surface waves, either implicitly or explicitly. In order to calculate the effect of wind forcing on waves and currents, and vice versa, it is necessary to employ a consistent formula- tion of the energy and momentum balance within the airflow, wave field, and water column. It is very advantageous to apply sur- face-following coordinate systems, whereby the steep gradients in mean flow properties near the air-water interface in the cross-interface direction may be resolved over distances which are much smaller than the height of the waves themselves. We may account for the waves explicitly by employing a numerical spectral wave model, and applying a suitable theory of wave–mean flow interaction. If the mean flow is small compared with the wave phase speed, perturbation expansions of the hydrodynamic equations in a Lagrangian or generalized Lagrangian mean framework are useful: for stronger flows, such as for wind blowing over waves, the presence of critical levels where the mean flow velocity is equal to the wave phase speed necessitates the application of more general types of surface-following coordinate system. The interaction of the flow of air and water and associated differences in temperature and the concentration of various substances (such as gas species) gives rise to a complex boundary-layer structure at a wide range of vertical scales, from the sub-millimetre scales of gaseous diffusion, to several tens of metres for the turbulent Ekman layer. The bal- ance of momentum, heat, and mass is also affected significantly by breaking waves, which act to increase the effective area of the surface for mass transfer, and increase turbulent diffusive fluxes via the conversion of wave energy to turbulent kinetic energy.

关键词： wind-wave-current interaction coordinate systems upper-ocean turbulence air-sea exchange of momentum, heat, andmass

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

Biochemical dissection of STAT3 signaling in amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第11期20卷 3229-3230页

作者： Savina Apolloni Nadia d’Ambrosi department of Biology University of Rome Tor VergataRomeItaly

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disease characterized by the loss of upper and lower motor neurons,clinically marked by muscle atrophy and *** the clinical course is highly variable,the average time from the onset of symptoms to the need for respiratory support or death is 3-5 *** is the most prevalent motor neuron disease in adults,occurring at a rate of 2 per 100,000 individuals and affecting 5.4 per 100,000 individuals overall.

关键词： STAT3 dissection sclerosis

Adjusting Temperature and Salinity Effects on Single Capacitance Sensors

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Pedosphere 2009年第5期19卷 588-596页

作者： A.FARES M.SAFEEQ d.M.jenkins department of Natural Resources and Environmental Management University of Hawaii at Manoa department of Molecular Biosciences and Bioengineering University of Hawaii at Manoa

Several newly developed capacitance sensors have simplified real-time determination of soil water *** work has shown that salinity and temperature can affect these sensors,but relatively little has been done to correct these *** objectives of this study were to evaluate the effect of media temperature and salinity on the apparent water content measured with a single capacitance sensor(SCS),and to mitigate this effect using a temperature dependent scaled voltage technique under laboratory conditions.A column study was conducted containing two media:pure deionized water and quartz sand under varying water contents(0.05 to 0.30 cm3 cm-3) and salinity(0 to 80 mmol L-1).Media temperature was varied between 5 and 45℃ using an *** SCS probes and thermocouples were placed in the middle of the columns and were logged at an interval of 1 *** was strong negative correlation between sensor reading and temperature of deionized water with a rate of-0.779 mV ℃-*** of SCS apparent output were 0.454 and 0.535 mV ℃-1 for air in heating and cooling cycles,respectively.A similar positive correlation with temperature was observed in sand at different water *** SCS probe was less sensitive to temperature as salinity and water content *** a temperature-corrected voltage calibration model,the effect of temperature was reduced by 98%.An analytical model for salinity correction was able to minimize the error as low as ± 2% over the salinity level tested.

关键词： calibration ECH2O probes quartz sand water content

Anti-amyloid antibodies in Alzheimer’s disease: what did clinical trials teach us?

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Neural Regeneration Research 2025年第4期20卷 1092-1093页

作者： danko Jeremic Lydia Jiménez-díaz Juan d.Navarro-López NeuroPhysiology&Behavior Lab University of Castilla-La ManchaBiomedical Research Center(CRIB)School of Medicine of Ciudad RealCiudad RealSpain

Although many causes of Alzheimer’s disease(Ad)may exist,both the original amyloid cascade and tau hypotheses posit that abnormal misfolding and accumulation of amyloid-β(Aβ)and tau protein is the central event causing the ***,that conclusion could be only partly true,and there is conflicting evidence about the role of both proteins in Ad,being able to precede and influence one *** researchers argue that these proteins are mere executors rather than primary causes of ***,there have been continuing refinements of both hypotheses,with alternative explanations proposed.Aβand tau proteins may be independently involved in specific neurotoxic pathways;yet there may be other crucial processes going on in early ***,accumulating evidence suggests that Aβand tau act synergistically,rather than additively in disease onset(Jeremic et al.,2021,2023a).

关键词： amyloid Alzheimer additive

Remaking a connection:molecular players involved in post-injury synapse formation

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Neural Regeneration Research 2025年第6期20卷 1719-1720页

作者： diogo Tomé Ramiro d.Almeida iBiMEd-Institute of Biomedicine Department of Medical SciencesUniversity of AveiroAveiroPortugal CNC-Center for Neuroscience and Cell Biology University of CoimbraCoimbraPortugal

Functional recovery from central nervous system(CNS)trauma depends not only on axon regeneration or compensatory sprouting of uninjured fibers but also on the ability of newly grown axons to establish functional synapses with appropriate *** several studies have successfully promoted long-distance axonal regeneration in distinct CNS injury models,none of them have resulted in a viable therapeutic approach for patient recovery.A possible reason may be the lack of new synaptogenesis for reestablishing the circuitry lost after ***,we discuss how our understanding of the mechanisms that instruct synapse formation in the injured nervous system may contribute to the design of new strategies to promote functional restoration in traumatic CNS disorders.

关键词： viable injury instru